FN Thomson Reuters Web of Science™ VR 1.0 PT J AU OGrady, WE Qian, X Ramaker, DE AF OGrady, WE Qian, X Ramaker, DE TI Systematic chemical effects observed in ''atomic'' X-ray absorption fine structure SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Letter ID EXAFS AB We report here, for the first time, large and systematic chemical effects on the ''atomic'' X-ray absorption fine structure (AXAFS) for a series of Pt-Ru alloys as a function of the composition and for an in situ Pt electrode as the electrode potential is increased. These changes are seen in the Fourier transform of the normal chi(E) function in XAFS, where the AXAFS produces a peak at the characteristic atomic radius. Curved-wave multiple-scattering cluster calculations (FEFF6) confirm the changes with alloy composition and electrode potential, although the theory overestimates the size of the changes. Obvious reasons for this are given. The systematic chemical effects and agreement with theoretical predictions provide strong support for their interpretation as AXAFS features, rather than multielectronic excitations. The AXAFS structure and its interpretation offers the promise of providing a new tool for observing in situ electronic (AXAFS) and geometric (normal EXAFS) structural changes simultaneously in complex systems where long range order is not required. C1 GEORGE WASHINGTON UNIV,DEPT CHEM,WASHINGTON,DC 20052. RP OGrady, WE (reprint author), USN,RES LAB,CODE 6170,WASHINGTON,DC 20375, USA. RI Qian, Xianghong/C-4821-2014 NR 13 TC 27 Z9 27 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JUL 17 PY 1997 VL 101 IS 29 BP 5624 EP 5626 DI 10.1021/jp970967y PG 3 WC Chemistry, Physical SC Chemistry GA XM058 UT WOS:A1997XM05800003 ER PT J AU Ratcliffe, CP AF Ratcliffe, CP TI Damage detection using a modified laplacian operator on mode shape data SO JOURNAL OF SOUND AND VIBRATION LA English DT Article ID LOCATION; IDENTIFICATION; COMPOSITE; DEFECTS AB Localized damage to a structure affects its dynamic properties, and much work has been undertaken investigating the variation of natural frequencies with damage. However, use of mode shape data has seen much less effort. This paper develops and presents a technique for identifying the location of structural damage in a beam. The procedure operates solely on the mode shape from the damaged structure, and does not require a priori knowledge of the undamaged structure. The procedure is developed using a one-dimensional finite element model of a beam, and demonstrated by experiment. When damage is severe (a localized thickness reduction of more than 10%), applying a finite difference approximation of Laplace's differential operator to the mode shape successfully identifies the location of the damage. However, when damage is less severe, further processing of the Laplacian output is required before the location can be determined. This post-processing enables the location of thickness reductions of less than 0.5% to be identified. The procedure is best suited to the mode shape obtained from the fundamental natural frequency. The mode shapes from higher natural frequencies can be used to verify the location of damage, but they are not as sensitive as the lower modes. (C) 1997 U.S. Government. RP Ratcliffe, CP (reprint author), USN ACAD,DEPT MECH ENGN,590 HOLLOWAY RD,ANNAPOLIS,MD 21402, USA. NR 42 TC 182 Z9 195 U1 1 U2 15 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0022-460X J9 J SOUND VIB JI J. Sound Vibr. PD JUL 17 PY 1997 VL 204 IS 3 BP 505 EP 517 DI 10.1006/jsvi.1997.0961 PG 13 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA XL378 UT WOS:A1997XL37800007 ER PT J AU Purdy, AP Berry, AD George, CF AF Purdy, AP Berry, AD George, CF TI Synthesis, structure, and thiolysis reactions of pyridine soluble alkaline earth and yttrium thiolates SO INORGANIC CHEMISTRY LA English DT Article ID CALCIUM LANTHANUM SULFIDE; CRYSTAL-STRUCTURES; THERMOLYSIS CHEMISTRY; OPTICAL-MATERIALS; COMPLEXES; METAL; MAGNESIUM; YTTERBIUM; LANTHANOID(III); STRONTIUM AB A series of alkaline earth thiolates, M(SR)(2) (M = Ca, Sr, Ba), were synthesized from reactions between M(NH2)(2) and RSH. For R = CMe3, the products were only slightly soluble in pyridine, but the Ca derivative with R = 1-adamantyl was soluble, and the Ca and Sr derivatives with R = CEt3 were very soluble in pyridine. All the R = SCMe3 derivatives dissolved in 1-methyl-2-pyrrolidinone (NMP). One yttrium thiolate, ((Et3SC)(2)Y(mu-SCEt3)Py-2)(2), was also prepared and characterized by single-crystal X-ray diffraction, as was (Sr(mu-SCEt3)(2)(NH3)Py)(n). The former crystallized as discrete dimers with planar (YS)(2) rings, and the latter formed an infinite chain of Sr atoms linked by thiolate bridges. Crystal data: ((Et3SC)(2)Y(mu-SCEt3)PY2)(2) P (1) over bar, a = 11.592(1) Angstrom, b = 17.328(2) Angstrom, c = 18.376(2) Angstrom, beta = 81.617(7)degrees, beta = 79.546(5)degrees, gamma = 78.169(7)degrees, and Z = 2; (Sr(mu-SCEt3)(2)(NH3)Py)(n) P2(1)/c, a = 9.332(2) Angstrom, b = 20.316(2) Angstrom, c = 13.024(1) Angstrom, beta = 102.879(9)degrees, and Z = 4. Solutions of Ca(SCEt3)(2) and Y(N(SiMe3)(2))(3) Or ((Et3SC)(2)Y(mu-SCEt3)PY2)(2) in pyridine were converted to gels or powders, respectively, by reaction with an excess of H2S, and the solids were pressed into pellets and thermolyzed to CaY2S4 under flowing H2S. C1 USN,RES LAB,STRUCT MATTER LAB,WASHINGTON,DC 20375. RP Purdy, AP (reprint author), USN,RES LAB,DIV CHEM,CODE 6120,WASHINGTON,DC 20375, USA. NR 39 TC 27 Z9 28 U1 1 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD JUL 16 PY 1997 VL 36 IS 15 BP 3370 EP 3375 DI 10.1021/ic970045+ PG 6 WC Chemistry, Inorganic & Nuclear SC Chemistry GA XL588 UT WOS:A1997XL58800024 ER PT J AU Narang, U Gauger, PR Ligler, FS AF Narang, U Gauger, PR Ligler, FS TI A displacement flow immunosensor for explosive detection using microcapillaries SO ANALYTICAL CHEMISTRY LA English DT Article ID NITROAROMATIC COMPOUNDS; LIQUID-CHROMATOGRAPHY; 2,4,6-TRINITROTOLUENE; IMMUNOASSAY; TNT; KINETICS; WATER; TRINITROTOLUENE; ANTIBODIES; SURFACES AB In this paper, we report on the characterization of a capillary-based displacement flow immunosensor for the explosive, 2,4,6-trinitrotoluene (TNT). Anti-TNT antibody is immobilized onto the silanized inner walls of a fused-silica capillary using a heterobifunctional cross-linker followed by saturating the capillary with fluorophore-labeled antigen, To perform the assay, an aliquot of target analyte solution is injected into the capillary column. The target analyte competes for the binding pocket of the fluorophore-labeled antigen, which is detected downstream. We have demonstrated that the sensitivity of the capillary-based immunosensor is improved by at least 3 orders of magnitude compared to packed-column or membrane-based displacement now immunosensors, We have investigated the effect of now rate and length of the capillary on the performance of the capillary immunosensor. We have demonstrated that, by the appropriate choice of an antibody, one can prepare a capillary immunosensor for the specific detection of TNT or as a detector for both TNT and its major metabolites. The limit of detection for TNT using the capillary immunosensor is 440 amol (100 mu L injection of 1 pg/mL TNT solution), The relative standard deviation (RSD) of the area under the peaks resulting from 10 back-to-back 100 mu L injections of 5 ng/mL TNT to the capillary immunosensor is 4%. The RSD for column-to-column variation is observed to be 5% (n = 5). The entire assay can be performed in less than 3 min. C1 USN, RES LAB, CTR BIOMOL SCI & ENGN, WASHINGTON, DC 20375 USA. NR 30 TC 59 Z9 59 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 EI 1520-6882 J9 ANAL CHEM JI Anal. Chem. PD JUL 15 PY 1997 VL 69 IS 14 BP 2779 EP 2785 DI 10.1021/ac970153d PG 7 WC Chemistry, Analytical SC Chemistry GA XK121 UT WOS:A1997XK12100024 ER PT J AU Dyka, CT Randles, PW Ingel, RP AF Dyka, CT Randles, PW Ingel, RP TI Stress points for tension instability in SPH SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING LA English DT Article DE SPH; explicit time integration; stability; stress points; staggered ID SMOOTHED PARTICLE HYDRODYNAMICS AB In this work, the stress-point approach, which was developed to address tension instability and improve accuracy in Smoothed Particle Hydrodynamics (SPH) methods, is further extended and applied for one-dimensional (1-D) problems. Details of the implementation of the stress-point method are also given. A stability analysis reveals a reduction in the critical time step by a factor of 1/root 2 when the stress points are located at the extremes of the SPH particle. An elementary damage law is also introduced into the 1-D formulation. Application to a 1-D impact problem indicates far less oscillation in the pressure at the interface for coarse meshes than with the standard SPH formulation. Damage predictions and backface velocity histories for a bar appear to be quite reasonable as well. In general, applications to elastic and inelastic 1-D problems are very encouraging. The stress-point approach produces stable and accurate results. (C) 1997 by John Wiley & Sons, Ltd. C1 FIELD COMMAND DEF NUCL AGCY,KIRTLAND AFB,NM 87117. USN,RES LAB,WASHINGTON,DC 20375. RP Dyka, CT (reprint author), GEOCENTERS INC,10903 INDIAN HEAD HIGHWAY,FT WASHINGTON,MD 20744, USA. NR 12 TC 91 Z9 101 U1 2 U2 11 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 0029-5981 J9 INT J NUMER METH ENG JI Int. J. Numer. Methods Eng. PD JUL 15 PY 1997 VL 40 IS 13 BP 2325 EP 2341 DI 10.1002/(SICI)1097-0207(19970715)40:13<2325::AID-NME161>3.0.CO;2-8 PG 17 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA XG294 UT WOS:A1997XG29400001 ER PT J AU Jensen, KL Kodis, MA Murphy, RA Zaidman, EG AF Jensen, KL Kodis, MA Murphy, RA Zaidman, EG TI Space charge effects on the current-voltage characteristics of gated field emitter arrays SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID EMISSION CATHODES AB Microfabricated field emitter arrays (FEAs) can provide the very high electron current densities required for rf amplifier applications, typically on the order of 100 A/cm(2). Determining the dependence of emission current on gate voltage is important for the prediction of emitter performance for device applications. Field emitters use high applied fields to extract current, and therefore, unlike thermionic emitters, the current densities can exceed 10(3) A/cm(2) when averaged over an array. At such high current densities, space charge effects (i.e., the influence of charge between cathode and collector on emission) affect the emission process or initiate conditions which can lead to failure mechanisms for field emitters. A simple model of a field emitter will be used to calculate the one-dimensional space charge effects on the emission characteristics by examining two components: charge between the gate and anode, which leads to Child's law, and charge within the FEA unit cell, which gives rise to a held suppression effect which can exist for a single held emitter. The predictions of the analytical model are compared with recent experimental measurements designed to assess space charge effects and predict the onset of gate current. It is shown that negative convexity on a Fowler-Nordheim plot of I-anode(V-gate) data can be explained in terms of field depression at the emitter tip in addition to reflection of electrons by a virtual cathode created when the anode field is insufficient to extract all of the current; in particular, the effects present within the unit cell constitute a newly described effect. RP Jensen, KL (reprint author), NAVAL RES LAB,ELECT SCI & TECHNOL DIV,CODE 6840,WASHINGTON,DC 20357, USA. RI Jensen, Kevin/I-1269-2015 OI Jensen, Kevin/0000-0001-8644-1680 NR 23 TC 33 Z9 33 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUL 15 PY 1997 VL 82 IS 2 BP 845 EP 854 DI 10.1063/1.365783 PG 10 WC Physics, Applied SC Physics GA XL731 UT WOS:A1997XL73100057 ER PT J AU Chu, PC Tseng, HC Chang, CP Chen, JM AF Chu, PC Tseng, HC Chang, CP Chen, JM TI South China Sea warm pool detected in spring from the Navy's Master Oceanographic Observational Data Set (MOODS) SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article AB A South China Sea warm pool with sea surface temperature (SST) higher than 29.5 degrees C, recently reported by Chu and Chang [1995a, b] and Chu et al. [1997], appears in the central South China Sea (west of the Luzon Island) in boreal spring, strengthens until the onset of the summer monsoon (mid-May), and then weakens and disappears at the end of May. The transient features and interannual variabilities of the warm pool have not yet been studied. Here we use a subset of the U.S. Navy's Master Oceanographic Observation Data Set (MOODS) to investigate the surface thermal features. First, we employed an optimal interpolation scheme to build up a 10-day interval synoptic data set for December 1963 to November 1984 on a 0.5 degrees x 1 degrees grids (finer resolution in zonal direction) from the MOODS SST data. An ensemble mean SST field (T) was established with a rather weak horizontal gradient (28.5 degrees C near the Palawan Island to 26 degrees C near the southeast China coast). Second, we performed a composite analysis to obtain the averaged SST anomaly field (T) over tilde deviating from the ensemble mean for the winter and spring seasons (December-May). During December-March, (T) over tilde is negative almost everywhere throughout the whole South China Sea. In early April, positive (T) over tilde with closed isoline (warm pool) was evident west of Luzon Island. In May, the central SCS warm anomaly becomes stronger. On May 11-20, the central SCS warm pool (114 degrees-119 degrees E, 14 degrees-19 degrees N) has (T) over tilde > 1.8 degrees C. The size of the warm pool is around 200,000 km(2). Third, we performed an empirical orthogonal function (EOF) analysis on the residue data ((T) over cap), deviating from T + (T) over tilde, for the winter and spring seasons, in order to obtain transient and interannual variations of the SST fields. EOF1 accounts for 35.5% of the variance and resembles the ensemble mean pattern of nearly parallel contours with a maximum value in the southeast and a minimum value in the northwest. EOF2 accounts for 21.4% of the variance and is characterized by a warm/cool pool (116 degrees-118 degrees E, 16 degrees-18 degrees N) west of the Luzon Island. The corresponding principal component (PC2) has strong interannual variability with a maximum value of 10 on February 11-20, 1965 and a minimum of -12 on March 21-31, 1964. This indicates the appearance of either a warm pool with a maximum strength of 1.2 degrees C or a cool pool with a maximum strength of -1 degrees C. Combination of (T) over tilde and PC2 x EOF2 leads to an occurrence of a central SCS warm pool from April to May with a warm anomaly varying between 0.8 degrees and 3 degrees C. C1 USN,POSTGRAD SCH,DEPT METEOROL,MONTEREY,CA 93943. RP Chu, PC (reprint author), USN,POSTGRAD SCH,DEPT OCEANOG,MONTEREY,CA 93943, USA. NR 16 TC 34 Z9 44 U1 2 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD JUL 15 PY 1997 VL 102 IS C7 BP 15761 EP 15771 DI 10.1029/97JC00628 PG 11 WC Oceanography SC Oceanography GA XL452 UT WOS:A1997XL45200016 ER PT J AU Elgar, S Guza, RT Raubenheimer, B Herbers, THC Gallagher, EL AF Elgar, S Guza, RT Raubenheimer, B Herbers, THC Gallagher, EL TI Spectral evolution of shoaling and breaking waves on a barred beach SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID SURFACE GRAVITY-WAVES; TRANSFORMATION; MODEL AB Field observations and numerical model predictions are used to investigate the effects of nonlinear interactions, reflection, and dissipation on the evolution of surface gravity waves propagating across a barred beach. Nonlinear interactions resulted in a doubling of the number of wave crests when moderately energetic (about 0.8-m significant wave height), narrowband swell propagated without breaking across an 80-m-wide, nearly flat (2-m depth) section of beach between a small offshore sand bar and a steep (slope = 0.1) beach face, where the waves finally broke. These nonlinear energy transfers are accurately predicted by a model based on the nondissipative, unidirectional (i.e., reflection is. neglected) Boussinesq equations. For a lower-energy (wave height about 0.4 m) bimodal wave field, high-frequency seas dissipated in the surf zone; but lower-frequency swell partially reflected from the steep beach face, resulting in significant cross-shore modulation of swell energy. The combined effects of reflection from the beach face and dissipation across the sand bar and near the shoreline are described well by a bore propagation model based on the nondispersive nonlinear shallow water equations. Boussinesq model predictions on the flat section (where dissipation is weak) are improved by decomposing the wave field into seaward and shoreward propagating components. In more energetic (wave heights greater than 1 m) conditions, reflection is negligible, and the region of significant dissipation can extend well seaward of the sand bar. Differences between observed decreases in spectral levels and Boussinesq model predictions of nonlinear energy transfers are used to infer the spectrum pf breaking wave induced dissipation between adjacent measurement locations. The inferred dissipation rates typically increase with increasing frequency and are comparable in magnitude to the nonlinear energy transfer rates. C1 USN,POSTGRAD SCH,DEPT OCEANOG,MONTEREY,CA 93943. UNIV CALIF SAN DIEGO,CTR COASTAL STUDIES 0209,LA JOLLA,CA 92093. RP Elgar, S (reprint author), WASHINGTON STATE UNIV,PULLMAN,WA 99164, USA. NR 25 TC 58 Z9 58 U1 0 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD JUL 15 PY 1997 VL 102 IS C7 BP 15797 EP 15805 DI 10.1029/97JC01010 PG 9 WC Oceanography SC Oceanography GA XL452 UT WOS:A1997XL45200019 ER PT J AU Ellison, JA Saenz, AW Nagl, A TapiaAguilar, JG AF Ellison, JA Saenz, AW Nagl, A TapiaAguilar, JG TI Energy dependence of the stability type of periodic orbits in a square lattice SO PHYSICA D LA English DT Article DE periodic orbits; stability; energy; Green's residue; nongeneric; channeling ID CHARGED-PARTICLES; HAMILTONIAN-SYSTEMS; CRYSTALS; MOTION; CHAOS AB We report the first numerical results of stability versus energy for short-period orbits pertaining to two nonrelativistic Hamiltonian models of channeling of charged particles in a square lattice. For both models, the orbits studied fall into two classes as regards the behavior of their Green's residue functions versus energy. The orbits in one of these classes exhibit nongeneric behavior near transition points of the relevant Poincare maps and those in the other class are ordinary hyperbolic at all energies investigated. C1 USN,RES LAB,WASHINGTON,DC 20375. UNIV NEW MEXICO,DEPT MATH,ALBUQUERQUE,NM 87131. CATHOLIC UNIV AMER,DEPT PHYS,WASHINGTON,DC 20064. APPL TECHNOMANAGEMENT SYST INC,FALLS CHURCH,VA 22043. INST POLITECN NACL,ESCUELA SUPER COMPUTO,MEXICO CITY 07738,DF,MEXICO. NR 23 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2789 J9 PHYSICA D JI Physica D PD JUL 15 PY 1997 VL 106 IS 1-2 BP 39 EP 48 DI 10.1016/S0167-2789(97)89484-5 PG 10 WC Mathematics, Applied; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA XM739 UT WOS:A1997XM73900003 ER PT J AU Carr, TW Schwartz, IB AF Carr, TW Schwartz, IB TI The role of symmetry breaking and disorder in the control of phase-ordered states in globally coupled oscillators SO PHYSICA D LA English DT Article DE coupled oscillators; symmetry breaking; noise; control ID JOSEPHSON-JUNCTION ARRAYS; SERIES ARRAYS; DYNAMICS; STABILITY AB We investigate the dynamics of splay-phase states, special out-of-phase states, in an array of globally coupled phase oscillators. Using asymptotic methods and a dimension reducing coordinate transformation we derive explicit representation for saddle shaped surfaces on which the dynamics is confined. The restricted motion is due to a high degree of neutral stability possessed by the splay-phase and related incoherent states. An additional consequence of the neutral stability is an extreme sensitivity to intrinsic noise which leads to diffusive drift. The elimination of this drift motivates an examination of the effect of parameter perturbations and their use for control. We have found that the system is uncontrollable using symmetry-preserving perturbations, but that symmetry-breaking perturbations effectively allow for the prevention of noise-induced drift. Finally, we have made observations on how general disorder affects the dynamics of the system; in particular, for small disorder certain sums of the phases become unbounded while others remain fixed. C1 USN,RES LAB,DIV PLASMA PHYS,SPECIAL PROJECT NONLINEAR SCI,WASHINGTON,DC 20375. RI Schwartz, Ira/A-8073-2009 NR 23 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2789 J9 PHYSICA D JI Physica D PD JUL 15 PY 1997 VL 106 IS 1-2 BP 113 EP 130 DI 10.1016/S0167-2789(97)00017-1 PG 18 WC Mathematics, Applied; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA XM739 UT WOS:A1997XM73900009 ER PT J AU Knipp, PA Reinecke, TL Lorke, A Fricke, M Petroff, PM AF Knipp, PA Reinecke, TL Lorke, A Fricke, M Petroff, PM TI Coupling between LO phonons and electronic excitations of quantum dots SO PHYSICAL REVIEW B LA English DT Article ID OPTICAL PHONONS; INGAAS; GAAS; SPECTROSCOPY AB The far-infrared response of self-assembled InxGa1-xAs quantum dots located a distance from a two-dimensional AlxGa1-xAs/GaAs interface has been studied as a function of magnetic field. An avoided crossing at about 45 meV, which involves the lowest electronic transition of the dots, has been observed. Calculations of the interaction between the excitations of these quantum dots and the LO phonons of the AlxGa1-xAs/GaAs interface have been made, and the resulting splitting has been found to be in agreement with the experimental results. The calculated dependence of the magnitude of the splitting on the separation between the dots and the nearest interface is consistent with the experimental results. C1 USN,RES LAB,WASHINGTON,DC 20375. UNIV MUNICH,SEKT PHYS,D-80539 MUNICH,GERMANY. UNIV CALIF SANTA BARBARA,DEPT MAT,SANTA BARBARA,CA 93106. UNIV CALIF SANTA BARBARA,QUEST,SANTA BARBARA,CA 93106. RP Knipp, PA (reprint author), CHRISTOPHER NEWPORT UNIV,DEPT PHYS & COMP SCI,NEWPORT NEWS,VA 23606, USA. RI Lorke, Axel/A-1170-2013 OI Lorke, Axel/0000-0002-0405-7720 NR 20 TC 25 Z9 27 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JUL 15 PY 1997 VL 56 IS 3 BP 1516 EP 1519 DI 10.1103/PhysRevB.56.1516 PG 4 WC Physics, Condensed Matter SC Physics GA XM766 UT WOS:A1997XM76600086 ER PT J AU Pompa, M Flank, AM Lagarde, P Rife, JC Stekhin, I Nakazawa, M Ogasawara, H Kotani, A AF Pompa, M Flank, AM Lagarde, P Rife, JC Stekhin, I Nakazawa, M Ogasawara, H Kotani, A TI Experimental and theoretical comparison between absorption, total electron yield, and fluorescence spectra of rare-earth M-5 edges SO PHYSICAL REVIEW B LA English DT Article ID X-RAY-ABSORPTION; SPECTROSCOPY; DICHROISM; EMISSION AB Besides the now well-known self-absorption effect, several phenomena related to the multiplet structure of the intermediate state may occur which render x-ray fluorescence different from the true absorption in 3d transition metals at the L edge and at the M-4,M-5 edges of rare earths. Special selection rules of the radiative de-excitation process play an important role there. We have measured the absorption coefficient of thin films of lanthanum, samarium, and thulium deposited on an aluminum foil, at room temperature, through the simultaneous detection of the transmission, total electron yield, and 150-eV bandwidth fluorescence yield. The latter result shows differences as compared to the other two, and exhibits polarization effects depending upon the angle between incident and outgoing photons. The resonant x-ray fluorescence spectrum is calculated using an atomic model, and then integrated over the emitted energy, to predict the fluorescence yield spectrum. Very good agreement is obtained between the theory and experiment. C1 USN,RES LAB,WASHINGTON,DC 20375. ROSTOV STATE UNIV,DEPT PHYS,ROSTOV NA DONU 344104,RUSSIA. UNIV TOKYO,INST SOLID STATE PHYS,MINATO KU,TOKYO 106,JAPAN. RP Pompa, M (reprint author), CTR UNIV ORSAY,UTILISAT RAYONNEMENT ELECTROMAGNET LAB,BATIMENT 209D,F-91405 ORSAY,FRANCE. NR 21 TC 23 Z9 24 U1 1 U2 10 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD JUL 15 PY 1997 VL 56 IS 4 BP 2267 EP 2272 DI 10.1103/PhysRevB.56.2267 PG 6 WC Physics, Condensed Matter SC Physics GA XY366 UT WOS:A1997XY36600082 ER PT J AU Singh, DJ Mazin, II AF Singh, DJ Mazin, II TI Calculated thermoelectric properties of La-filled skutterudites SO PHYSICAL REVIEW B LA English DT Article ID COSB3; TRANSPORT; ANTIMONIDES AB The thermoelectric properties of La-filled skutterudites are discussed from the point of view of their electronic structures. These are calculated from first principles within the local-density approximation. The electronic structure is in turn used to determine transport related quantities. Virtual-crystal calculations for La(Fe,Co)(4)Sb-12 show that the system obeys near rigid band behavior with varying Co concentration, and has a substantial band gap at a position corresponding to the composition LaFe3CoSb12. The valence-band maximum occurs at the Gamma point and is due to a singly degenerate dispersive band, which by itself would not be favorable for high thermopower. However, very flat transition-metal-derived bands occur in close proximity and become active as the doping level is increased, giving a nontrivial dependence of the properties on carrier concentration and explaining the favorable thermoelectric properties. C1 GEORGE MASON UNIV,CSI,FAIRFAX,VA 22030. RP Singh, DJ (reprint author), USN,RES LAB,CODE 6691,WASHINGTON,DC 20375, USA. RI Mazin, Igor/B-6576-2008; Singh, David/I-2416-2012 NR 17 TC 188 Z9 189 U1 2 U2 20 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD JUL 15 PY 1997 VL 56 IS 4 BP R1650 EP R1653 PG 4 WC Physics, Condensed Matter SC Physics GA XY366 UT WOS:A1997XY36600002 ER PT J AU Bassani, MHD Perepezko, JH Edelstein, AS Everett, RK AF Bassani, MHD Perepezko, JH Edelstein, AS Everett, RK TI Initial phase evolution during interdiffusion reactions SO SCRIPTA MATERIALIA LA English DT Article ID AL/NI MULTILAYERS; NUCLEATION; INTERFACES; DIFFUSION; KINETICS C1 USN,RES LAB,WASHINGTON,DC 20375. RP Bassani, MHD (reprint author), UNIV WISCONSIN,DEPT MAT SCI & ENGN,1509 UNIV AVE,MADISON,WI 53706, USA. OI Everett, Richard/0000-0002-6725-9442 NR 16 TC 23 Z9 24 U1 1 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD JUL 15 PY 1997 VL 37 IS 2 BP 227 EP 232 DI 10.1016/S1359-6462(97)00078-X PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA XF621 UT WOS:A1997XF62100017 ER PT J AU Griscom, DL AF Griscom, DL TI Radiation hardening of pure-silica-core optical fibers: Reduction of induced absorption bands associated with self-trapped holes SO APPLIED PHYSICS LETTERS LA English DT Article ID DIOXIDE AB Visible/near-IR-range radiation hardening of a pair of low-OH/low-Cl silica-core optical fibers has been accomplished by gamma-ray preirradiation at 27 C to a dose of 13 MGy(Si) at a dose rate of 1 Gy(Si)/s in the dark. Reirradiation under identical conditions three months later demonstrated a 25-fold decrease in the initially induced intensities of the prominent radiation-induced bands centered near 660 and 760 nm and comparable decreases in weaker bands at longer and shorter wavelengths. Spectral changes observed in the wavelength regime 400-1000 nm upon quenching the irradiated fibers to 77 K have revealed the likely copresence, even at room temperature, of a previously reported ''low temperature infrared absorption'' which peaks near 1600 nm. Based on this insight, induced losses at 1550 nm have been extrapolated from the present data. It is argued that self-trapped holes are most likely responsible for most of the metastable induced absorption bands in the range similar to 400-2000 nm. (C) 1997 American Institute of Physics. RP Griscom, DL (reprint author), USN,RES LAB,DIV OPT SCI,WASHINGTON,DC 20375, USA. RI shao, chongyun/M-6620-2013 NR 14 TC 31 Z9 31 U1 0 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JUL 14 PY 1997 VL 71 IS 2 BP 175 EP 177 DI 10.1063/1.119493 PG 3 WC Physics, Applied SC Physics GA XK160 UT WOS:A1997XK16000009 ER PT J AU Pinto, JF Esterowitz, L AF Pinto, JF Esterowitz, L TI Distributed-feedback, tunable Ce3+-doped colquiriite lasers SO APPLIED PHYSICS LETTERS LA English DT Article ID DYE-LASER AB Distributed-feedback (dfb) laser oscillation is reported in Ce3+-doped LiSrAlF6 (LiSAF). Tunable operation of the Ce3+:LiSAF dfb laser is achieved in the ultraviolet wavelength region from 289 to 293 nm. At the peak emission wavelength of 290 nm, dfb lasing linewidths are less than the 1 Angstrom resolution limit of the 1 m spectrometer. (C) 1997 American Institute of Physics. RP Pinto, JF (reprint author), USN,RES LAB,CODE 5641,WASHINGTON,DC 20375, USA. NR 13 TC 10 Z9 10 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JUL 14 PY 1997 VL 71 IS 2 BP 205 EP 207 DI 10.1063/1.119501 PG 3 WC Physics, Applied SC Physics GA XK160 UT WOS:A1997XK16000019 ER PT J AU Jackson, EM Weaver, BD Summers, GP AF Jackson, EM Weaver, BD Summers, GP TI Proton damage effects in YBa2Cu3O7/YBa2Cu2.79C0.21O7/YBa2Cu3O7 Josephson junctions SO APPLIED PHYSICS LETTERS LA English DT Article ID YBA2CU3O7-DELTA; IRRADIATION; TEMPERATURE; FILMS AB The effects of proton-induced defects on the properties of superconductor-normal-superconductor Josephson junctions with YBa2Cu2.79Co0.21O7 barriers have been investigated. The resistance (R) increases linearly and the critical current (I-c) decreases exponentially with fluence, respectively. Changes in I-c and R occur only at fluences which also reduce T-c. The results indicate that point defects probably have little influence on the uniformity of the I-c and R injunction arrays. (C) 1997 American Institute of Physics. C1 USN,RES LAB,WASHINGTON,DC 20375. UNIV MARYLAND BALTIMORE CTY,BALTIMORE,MD 21228. RP Jackson, EM (reprint author), SFA INC,LANDOVER,MD 20875, USA. NR 15 TC 6 Z9 6 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JUL 14 PY 1997 VL 71 IS 2 BP 273 EP 275 DI 10.1063/1.119517 PG 3 WC Physics, Applied SC Physics GA XK160 UT WOS:A1997XK16000042 ER PT J AU Freeland, JW Chakarian, V Idzerda, YU Doherty, S Zhu, JG Park, JH Kao, CC AF Freeland, JW Chakarian, V Idzerda, YU Doherty, S Zhu, JG Park, JH Kao, CC TI Identifying layer switching in magnetic multilayers with x-ray resonant magnetic scattering SO APPLIED PHYSICS LETTERS LA English DT Article ID CIRCULAR-DICHROISM; GIANT MAGNETORESISTANCE; EXCHANGE SCATTERING; EDGES; IRON AB The order of layer switching in a NiFe/Cu/Co spin valve is determined directly using circular polarized x-ray resonant magnetic scattering. By monitoring changes in the angular dependence of the magnetic contributions to the reflectivity near the Fe L-3 and Co L-3 edges asa function of applied field, the order of layer switching is directly obtained. (C) 1997 American Institute of Physics. C1 USN,RES LAB,WASHINGTON,DC 20375. UNIV MINNESOTA,DEPT ELECT ENGN,MINNEAPOLIS,MN 55455. NR 24 TC 17 Z9 17 U1 1 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JUL 14 PY 1997 VL 71 IS 2 BP 276 EP 278 DI 10.1063/1.119518 PG 3 WC Physics, Applied SC Physics GA XK160 UT WOS:A1997XK16000043 ER PT J AU Bennetto, J Nunes, RW Vanderbilt, D AF Bennetto, J Nunes, RW Vanderbilt, D TI Period-doubled structure for the 90 degrees partial dislocation in silicon SO PHYSICAL REVIEW LETTERS LA English DT Article ID TOTAL-ENERGY CALCULATIONS; ELECTRONIC-STRUCTURE; SEMICONDUCTORS; MODEL; CORE AB We suggest that the commonly accepted core structure of the 90 degrees partial dislocation in Si may not be correct, and propose instead a period-doubled structure. We present local-density approximation, tight-binding, and classical Keating-model calculations, all of which indicate that the period-doubled structure is lower in energy. The new structure displays a broken mirror symmetry in addition to the period doubling, leading to a wide variety of possible solitonlike defects and kinks. C1 USN,RES LAB,COMPLEX SYST THEORY BRANCH,WASHINGTON,DC 20375. GEORGE MASON UNIV,INST COMPUTAT SCI,FAIRFAX,VA. RP Bennetto, J (reprint author), RUTGERS STATE UNIV,DEPT PHYS & ASTRON,POB 849,PISCATAWAY,NJ 08855, USA. RI Nunes, Ricardo Wagner/M-9974-2014 OI Nunes, Ricardo Wagner/0000-0003-2810-8649 NR 25 TC 98 Z9 99 U1 1 U2 9 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JUL 14 PY 1997 VL 79 IS 2 BP 245 EP 248 DI 10.1103/PhysRevLett.79.245 PG 4 WC Physics, Multidisciplinary SC Physics GA XK293 UT WOS:A1997XK29300017 ER PT J AU Fender, RP Burnell, SJB Waltman, EB Pooley, GG Ghigo, FD Foster, RS AF Fender, RP Burnell, SJB Waltman, EB Pooley, GG Ghigo, FD Foster, RS TI Cygnus X-3 in outburst: quenched radio emission, radiation losses and variable local opacity SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE binaries, close; stars, individual, Cyg X-3; radio continuum, stars ID 8.3 GHZ; EXPANSION; 0.35C AB We present multiwavelength observations of Cygnus X-3 during an extended outburst in 1994 February-March. Intensive radio monitoring at 13.3, 3.6 and 2.0 cm is complemented by observations at (sub)millimetre and infrared wavelengths, which find Cyg X-3 to be unusually bright and variable, and include the first reported detection of the source at 0.45 mm. We report the first confirmation of quenched radio emission prior to radio flaring independently of observations at Green Bank. The observations reveal evidence for wavelength-dependent radiation losses and gradually decreasing opacity in the environment of the radio jet. We find that the radiation losses are likely to be predominantly inverse Compton losses experienced by the radio-emitting electrons in the strong radiation field of a luminous companion to the compact object. We interpret the decreasing opacity during the flare sequence as resulting from a decreasing proportion of thermal electrons entrained in the jet, reflecting a decreasing density in the region of jet formation. We present, drawing in part on the work of other authors, a model based upon mass transfer rate instability predicting gamma-ray, X-ray, infrared and radio trends during a radio flaring sequence. C1 UNIV SUSSEX,CTR ASTRON,BRIGHTON BN1 9QH,E SUSSEX,ENGLAND. USN,RES LAB,REMOTE SENSING DIV,WASHINGTON,DC 20375. UNIV CAMBRIDGE,CAVENDISH LAB,MULLARD RADIO ASTRON OBSERV,CAMBRIDGE CB3 0HE,ENGLAND. NATL RADIO ASTRON OBSERV,GREEN BANK,WV 24944. RP Fender, RP (reprint author), OPEN UNIV,DEPT PHYS,WALTON HALL,MILTON KEYNES MK7 6AA,BUCKS,ENGLAND. NR 41 TC 25 Z9 25 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0NE SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD JUL 11 PY 1997 VL 288 IS 4 BP 849 EP 858 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XL795 UT WOS:A1997XL79500005 ER PT J AU Gierlinski, M Zdziarski, AA Done, C Johnson, WN Ebisawa, K Ueda, Y Haardt, F Philips, BF AF Gierlinski, M Zdziarski, AA Done, C Johnson, WN Ebisawa, K Ueda, Y Haardt, F Philips, BF TI Simultaneous X-ray and gamma-ray observations of Cyg X-1 in the hard state by Ginga and OSSE SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE accretion, accretion discs; stars, individual, Cygnus X-1; gamma-rays, observations; gamma-rays, theory; X-rays, stars ID RELATIVISTIC THERMAL PLASMAS; ACTIVE GALACTIC NUCLEI; PAIR PRODUCTION; ORBITAL INCLINATION; ACCRETION DISKS; COMPACT SOURCES; EMISSION; SPECTRUM AB We present four X-ray/gamma-ray spectra of Cyg X-1 observed in the hard ('low') state simultaneously by Ginga and GRO OSSE on 1991 June 6. The four spectra have almost identical spectral form but vary in normalization within a factor of 2. The 3-30 keV Ginga spectra are well represented by power laws with an energy spectral index of alpha similar to 0.6 and a Compton reflection component including a fluorescent Fe K alpha corresponding to the solid angle of the reflector of similar to 0.3 x 2 pi. These spectra join smoothly on to the OSSE range (greater than or equal to 50 keV) and are then cut off above similar to 150 keV. The overall spectra can be modelled by repeated Compton scattering in a mildly relativistic, thermal plasma with an optical depth of tau similar to 1. However, the high-energy cut-off is steeper than that due to single-temperature thermal Comptonization, It can be described by a superposition of dominant tau similar to 1-2, thermal emission at kT similar to 100 keV and a Wien-like component from an optically thick plasma at kT similar to 50 keV. The X-ray spectra do not show the presence of the anisotropy break required if thermal Compton scattering takes place in a corona above a cold disc, Also, the flat spectral index shows that the plasma is soft-photon starved, i.e., the luminosity in incident soft X-ray seed photons is very much less than that in the hard X-rays. Furthermore, the observed solid angle of the reflector is significantly less than 2 pi. These facts taken together strongly rule out a disc-corona geometry, Rather, the observed spectra are consistent with a geometry in which the cold accretion disc (which both supplies the seed soft X-rays and reflects hard X-rays) only exists at large radii, while the Comptonizing hot plasma is located in an inner region with no cold disc, This hot plasma consists of pure e(+/-) pairs if the source size is similar to 5 Schwarzschild radii or it also contains protons if the size is larger. C1 NICHOLAS COPERNICUS ASTRON CTR,PL-00716 WARSAW,POLAND. NASA,GODDARD SPACE FLIGHT CTR,HIGH ENERGY ASTROPHYS LAB,GREENBELT,MD 20771. UNIV DURHAM,DEPT PHYS,DURHAM DH1 3LE,ENGLAND. USN,RES LAB,EO HULBURT CTR SPACE RES,WASHINGTON,DC 20375. INST SPACE & ASTRONAUT SCI,SAGAMIHARA,KANAGAWA 229,JAPAN. GOTHENBURG UNIV,DEPT ASTRON & ASTROPHYS,S-41296 GOTHENBURG,SWEDEN. UNIV SPACE RES ASSOC,WASHINGTON,DC 20024. RP Gierlinski, M (reprint author), JAGIELLONIAN UNIV,ASTRON OBSERV,ORLA 171,PL-30244 KRAKOW,POLAND. RI Johnson, Neil/G-3309-2014; done, chris/D-4605-2016; OI done, chris/0000-0002-1065-7239; Gierlinski, Marek/0000-0001-9149-3514 NR 42 TC 228 Z9 229 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0NE SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD JUL 11 PY 1997 VL 288 IS 4 BP 958 EP 964 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XL795 UT WOS:A1997XL79500011 ER PT J AU Skibo, JG Johnson, WN Kurfess, JD Kinzer, RL Jung, G Grove, JE Purcell, WR Ulmer, MP Gehrels, N Tueller, J AF Skibo, JG Johnson, WN Kurfess, JD Kinzer, RL Jung, G Grove, JE Purcell, WR Ulmer, MP Gehrels, N Tueller, J TI OSSE observations of the soft gamma-ray continuum from the galactic plane at longitude 95 degrees SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmic rays; gamma rays, observations; ISM, general; supernova remnants ID SUPERNOVA REMNANT; EMISSION; RADIATION; GALAXY; 4U-2129+47; POWER AB We present the results of OSSE observations of the soft gamma-ray continuum emission from the Galactic plane at longitude 95 degrees. Emission is detected between 50 and 600 keV where the spectrum is fitted well by a power law with photon index -2.6 +/- 0.3 and flux (4.0 +/- 0.5) x 10(-2) photons s(-1) cm(-2) rad(-1) MeV-1 at 100 keV. This spectral shape in this range is similar to that found for the continuum emission from the inner Galaxy, but the amplitude is lower by a factor of 4. This emission is due to either unresolved and previously unknown point sources, or diffuse electron bremsstrahlung, or a combination of the two. Simultaneous observations with OSSE and smaller field-of-view instruments operating in the soft gamma-ray energy band, such as X-ray Timing Explorer or Beppo-SAX, would help resolve this issue. If it is primarily diffuse emission due to nonthermal electron bremsstrahlung, as is the >1 MeV Galactic ridge continuum, then the power in low-energy cosmic-ray electrons exceeds that of the nuclear component of the cosmic rays by an order of magnitude. This would have profound implications for the origin of cosmic rays and the energetics of the interstellar medium. Alternatively, if the emission is diffuse and thermal, then there must be a component of the interstellar medium at temperatures similar to 10(9) K. C1 NORTHWESTERN UNIV,EVANSTON,IL 60208. NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. RP Skibo, JG (reprint author), USN,RES LAB,EO HULBURT CTR SPACE RES,CODE 7653,WASHINGTON,DC 20375, USA. RI Gehrels, Neil/D-2971-2012; Tueller, Jack/D-5334-2012; Johnson, Neil/G-3309-2014 NR 44 TC 25 Z9 25 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUL 10 PY 1997 VL 483 IS 2 BP L95 EP L98 DI 10.1086/310755 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XL756 UT WOS:A1997XL75600006 ER PT J AU Lin, CS AF Lin, CS TI Waveform sampling lidar applications in complex terrain SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID LASER AB This paper describes waveform sampling lidar systems for airborne remote sensing applications. Measurements over complex terrains and open ocean using these lidar systems are described. The lidar detected terrain features during these experiments included forested lands, farm lands, cleared lands, farm roads and lake water. Lidar waveform characteristics as a function of these terrain features are described. Comparisons of lidar waveform over lake water and ocean water are also described. RP Lin, CS (reprint author), USN,RES LAB,CODE 7230,WASHINGTON,DC 20375, USA. NR 10 TC 7 Z9 7 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD JUL 10 PY 1997 VL 18 IS 10 BP 2087 EP 2104 DI 10.1080/014311697217774 PG 18 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA XH143 UT WOS:A1997XH14300003 ER PT J AU Hill, EA Yesinowski, JP AF Hill, EA Yesinowski, JP TI Solid-state N-14 nuclear magnetic resonance techniques for studying slow molecular motions SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID DEUTERON SPIN ALIGNMENT; SELECTIVE EXCITATION; TETRAHEDRAL JUMPS; NMR; HEXAMETHYLENETETRAMINE; RELAXATION; EXCHANGE; POLYMERS AB A variety of transition-selective solid-state N-14 (1 = 1)NMR techniques are demonstrated for the first time to be useful for quantitatively describing;slow molecular motions in the solid state. These techniques are validated by quantitative measurements of molecular reorientation by tetrahedral jumps in hexamethylenetetramine (HMT). A new four-site magnetization-exchange model, capable of being generalized to n-sites, which includes the effects of spin-lattice relaxation is developed. This model provides the limiting conditions under which the orientation dependence of spin-lattice relaxation values T-1 can be safely neglected. The model is used to analyze results from a frequency-selective DANTE train used to burn a hole in the spectrum, that provide a direct indication of the existence of 4-site exchange. The measured correlation time for the motion in HMT of 103+/-6 ms at room temperature agrees well with previous studies by other techniques. In a novel application to molecular dynamics, the repeated hole-burning pulse trains of the SINK experiment are used to measure a magnetization recovery time constant due to N-14 spin-lattice relaxation in HMT of 0.99 +/- 0.12 s. Both experiments employ frequency-selective as well as transition-selective radio frequency pulses on a relatively small frequency region (<100 kHz) of the entire quadrupolar powder pattern of HMT (NQCC=4.414 MHz, eta=0). The Hahn spin-echo used for detection can be understood in terms of the fictitious spin-1/2 formalism. Quantitative dynamical information is obtained from measurements at only one frequency position of a wide inhomogeneously broadened powder pattern. Because we are operating in this unusual regime, the sensitivity can be significantly improved by replacing the DANTE hole-burning train with a series of pi/2 pulses that saturate all observable magnetization. Results from such an experiment compare well with those obtained using DANTE trains. (C) 1997 American Institute of Physics. C1 USN,RES LAB,WASHINGTON,DC 20375. NR 35 TC 22 Z9 22 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUL 8 PY 1997 VL 107 IS 2 BP 346 EP 354 DI 10.1063/1.474609 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA XH838 UT WOS:A1997XH83800007 ER PT J AU Gammon, D Brown, SW Snow, ES Kennedy, TA Katzer, DS Park, D AF Gammon, D Brown, SW Snow, ES Kennedy, TA Katzer, DS Park, D TI Nuclear spectroscopy in single quantum dots: Nanoscopic Raman scattering and nuclear magnetic resonance SO SCIENCE LA English DT Article ID WELL STRUCTURES; EXCITONS; PHONONS AB Resonant Raman and nuclear magnetic resonance spectroscopies from single gallium arsenide quantum dots are demonstrated. The nuclei were probed through changes in the optical spectra of the quantum dot exciton arising from exciton-nuclear interactions. This approach allowed the application of optical spectroscopy with its extremely high sensitivity and selectivity. The experiments had a lateral spatial resolution of about 10 nanometers and probe a volume that was five orders of magnitude smaller than that of previous semiconductor nuclear spectroscopic studies. RP Gammon, D (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. RI Katzer, D. Scott/N-7841-2013 NR 26 TC 141 Z9 143 U1 2 U2 30 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD JUL 4 PY 1997 VL 277 IS 5322 BP 85 EP 88 DI 10.1126/science.277.5322.85 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA XJ418 UT WOS:A1997XJ41800044 ER PT J AU Lambert, RJ Bhar, TN Lawrence, RK Hughes, HL Allen, L AF Lambert, RJ Bhar, TN Lawrence, RK Hughes, HL Allen, L TI Measurement of hole traps in SIMOX oxide by avalanche injection SO ELECTRONICS LETTERS LA English DT Article DE SIMOX; silicon-on-insulator AB Avalanche hole injection into a buried oxide formed by ion implantation is successfully used to determine the effective hole trap densities and the corresponding capture cross-sections. The material used for this study was a standard commercial wafer, fabricated by the separation-by-implantation-of-oxygen process. Analysis of the mid-gap voltage shift in the high frequency capacitance-voltage curve against injected charge reveals the existence of three distinct hole traps with cross-sections about 10 times larger than those found for thermal oxides. C1 ARACOR, OXON HILL, MD 20745 USA. USN, RES LAB, WASHINGTON, DC 20375 USA. IBIS TECHNOL CORP, DANVERS, MA 01923 USA. RP COLUMBIA UNIV, WASHINGTON, DC 20008 USA. NR 6 TC 0 Z9 0 U1 0 U2 1 PU INST ENGINEERING TECHNOLOGY-IET PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 0013-5194 EI 1350-911X J9 ELECTRON LETT JI Electron. Lett. PD JUL 3 PY 1997 VL 33 IS 14 BP 1264 EP 1265 DI 10.1049/el:19970813 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA XM128 UT WOS:A1997XM12800054 ER PT J AU Russell, MW Freitas, JA Moore, WJ Butler, JE AF Russell, MW Freitas, JA Moore, WJ Butler, JE TI Morphological evolution, Raman and photoluminescence spectra in optically transparent cubic silicon carbide SO ADVANCED MATERIALS FOR OPTICS AND ELECTRONICS LA English DT Article DE cubic silicon carbide; morphology; photoluminescence; micro-Raman ID CHEMICAL-VAPOR-DEPOSITION; GROWTH-CHARACTERISTICS; BETA; SI AB Optically transparent cubic SiC crystals were grown via atmospheric-pressure chemical vapour deposition (APCVD) on graphite substrates from methyltrichlorosilane (MTS) in hydrogen in a cold-wall RF induction furnace at temperatures from 1500 to 2000 degrees C, The morphology of the crystals was correlated to substrate temperature, H-2/MTS ratio and hydrogen flow, Low-temperature photoluminescence (PL) spectra exhibited a zero-phonon line (2.3787 eV) attributable to an exciton bound to a neutral nitrogen donor, in addition to TA, LA, TO, and LO phonon replicas, The observed broadening and splitting of the PL spectral lines were associated with the morphological habit and internal strain of individual crystallites. Above about 1600 degrees C preferential [110] growth directions were identified for the majority of the crystals, At intermediate deposition temperatures (1600-1700 degrees C) the dominant morphology consisted of yellow prismatic crystals heavily twinned along {111} and {11 (1) over bar}, At temperatures of about 1750 degrees C hexagonally shaped {111}-oriented 3C-SiC platelets were formed with alternating {001}/{101} edges. A layer-by-layer growth model was used to rationalise the transition in preferred growth direction from [111] to [101] with increasing substrate temperature. (C) 1997 by John Wiley & Sons, Ltd. C1 USN,RES LAB,DIV ELECT SCI & TECHNOL,WASHINGTON,DC 20375. RP Russell, MW (reprint author), USN,RES LAB,DIV CHEM,CODE 6174,WASHINGTON,DC 20375, USA. RI Butler, James/B-7965-2008 OI Butler, James/0000-0002-4794-7176 NR 32 TC 6 Z9 6 U1 0 U2 11 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 1057-9257 J9 ADV MATER OPT ELECTR JI Adv. Mater. Opt. Electron. PD JUL-AUG PY 1997 VL 7 IS 4 BP 195 EP 206 DI 10.1002/(SICI)1099-0712(199707)7:4<195::AID-AMO306>3.0.CO;2-4 PG 12 WC Chemistry, Applied; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Optics SC Chemistry; Engineering; Materials Science; Optics GA XP962 UT WOS:A1997XP96200004 ER PT J AU Schmitt, MN Grunawalt, RJ AF Schmitt, MN Grunawalt, RJ TI Land and maritime zones of peace in international law - Subedi,SP SO AMERICAN JOURNAL OF INTERNATIONAL LAW LA English DT Book Review RP Schmitt, MN (reprint author), USN WAR COLL,NEWPORT,RI 02841, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC INT LAW PI WASHINGTON PA 2223 MASSACHUSETTS AVE N W, WASHINGTON, DC 20008-2864 SN 0002-9300 J9 AM J INT LAW JI Am. J. Int. Law PD JUL PY 1997 VL 91 IS 3 BP 568 EP 570 PG 3 WC International Relations; Law SC International Relations; Government & Law GA XM788 UT WOS:A1997XM78800016 ER PT J AU Hoyt, RE AF Hoyt, RE TI Popcorn, pica, and impaction SO AMERICAN JOURNAL OF MEDICINE LA English DT Article RP Hoyt, RE (reprint author), USN HOSP,PENSACOLA,FL, USA. NR 3 TC 3 Z9 3 U1 0 U2 0 PU EXCERPTA MEDICA INC PI NEW YORK PA 245 WEST 17TH STREET, NEW YORK, NY 10011 SN 0002-9343 J9 AM J MED JI Am. J. Med. PD JUL PY 1997 VL 103 IS 1 BP 70 EP 70 PG 1 WC Medicine, General & Internal SC General & Internal Medicine GA XL324 UT WOS:A1997XL32400010 PM 9236488 ER PT J AU Ross, G Chapman, AW Newberg, AR Scheller, AD AF Ross, G Chapman, AW Newberg, AR Scheller, AD TI Magnetic resonance imaging for the evaluation of acute posterolateral complex injuries of the knee SO AMERICAN JOURNAL OF SPORTS MEDICINE LA English DT Article ID ROTATORY INSTABILITY; POSTERIOR CRUCIATE; LIGAMENT AB Clinical evaluation of posterolateral complex injuries of the knee can be difficult. To determine if magnetic resonance imaging can assist in decision-making in the treatment of posterolateral complex injuries, six consecutive patients with acute posterolateral knee trauma were imaged preoperatively with standard magnetic resonance imaging sequences. Magnetic resonance imaging findings were then correlated with results of examination under anesthesia or open lateral reconstruction. There were five complete lateral complex injuries (grade III) and one partial tear. Magnetic resonance imaging was able to accurately depict the extent of injury preoperatively in each case. All patients had concomitant anterior cruciate ligament tears. There was one partial posterior cruciate ligament tear. Visualization of the arcuate complex, biceps femoris tendon, lateral capsule, iliotibial band, popliteal tendon, and lateral collateral ligament was possible. A characteristic bone contusion on the anteromedial femoral condyle was present in all patients with complete posterolateral disruptions. Lateral complex injuries of the knee can be very accurately demonstrated on magnetic resonance imaging, and this imaging technique can be used to clarify the exact nature of the injury to allow better surgical planning. C1 NEW ENGLAND BAPTIST HOSP,DEPT RADIOL,BOSTON,MA. NEW ENGLAND BONE & JOINT INST,DEPT ORTHOPAED SURG,SECT SPORTS MED,BOSTON,MA. RP Ross, G (reprint author), USN ACAD,NAVAL MED CLIN,DEPT ORTHOPAED SURG,ANNAPOLIS,MD 21402, USA. NR 21 TC 48 Z9 50 U1 1 U2 1 PU AMER ORTHOPAEDIC SOC SPORT MED PI WALTHAM PA 230 CALVARY STREET, WALTHAM, MA 02154 SN 0363-5465 J9 AM J SPORT MED JI Am. J. Sports Med. PD JUL-AUG PY 1997 VL 25 IS 4 BP 444 EP 448 DI 10.1177/036354659702500405 PG 5 WC Orthopedics; Sport Sciences SC Orthopedics; Sport Sciences GA XM181 UT WOS:A1997XM18100005 PM 9240976 ER PT J AU Corwin, A Putri, MP Winarno, J Lubis, I Suparmanto, S Sumardiati, A Laras, K Tan, R Master, J Warner, G Wignall, FS Graham, R Hyams, KC AF Corwin, A Putri, MP Winarno, J Lubis, I Suparmanto, S Sumardiati, A Laras, K Tan, R Master, J Warner, G Wignall, FS Graham, R Hyams, KC TI Epidemic and sporadic hepatitis E virus transmission in West Kalimantan (Borneo), Indonesia SO AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE LA English DT Article AB A cross-sectional survey was conducted in West Kalimantan (Borneo), Indonesia to geographically profile hepatitis E virus (HEV) prevalence in the riverine areas recognized as the foci of epidemic HEV transmission in 1987. Additionally, a contiguous, although distinct, population with no identifiable historical exposure to epidemic HEV was surveyed downstream for comparative purposes. Eight hundred eighty-five sera were assayed by enzyme immunoabsorbent assay for anti-HEV IgG and anti-hepatitis A virus (HAV) IgG markers. A very high percent (90%) of both the outbreak and comparison populations was anti-HAV IgG positive by the age of nine years. In contrast, the prevalence of anti-HEV IgG in the outbreak area (50%) was significantly higher than in the comparison area (23%) (P < 0.0001). In both the outbreak and comparison areas, anti-HEV IgG prevalence increased with age (< 0.0001), except for the group greater than or equal to 50 years of age. The prevalence (53%) of antibody to HEV in the population greater than or equal to seven years of age from the outbreak area (alive during the actual 1987 outbreak) was significantly (P < 0.0001) greater than among the children < seven years of age (born after the outbreak) (15%). However, anti-HEV IgG prevalence among the population from the comparison area did not differ significantly between the greater than or equal to seven- (23%) and < seven- (20%) year-old age groups. The percentage of anti-HEV IgG-positive individuals among males (47%) from the outbreak area was lower (P < 0.05) compared with females (55%). While overall usage of river water for drinking purposes was not universal, dependence on river water as a primary source was significantly higher (P < 0.001) in households from the outbreak area (60%) compared with the comparison area (30%). This study indicates persistence of an anti-HEV IgG response in a large percentage of the population seven years after an epidemic of HEV infections. Also, the relatively high prevalence (15%) of anti-HEV in children , seven years of age from the outbreak area reflects continuing, sporadic infections. C1 PROV HLTH SERV, JAYAPURA, SINTANG, INDONESIA. NATL INST HLTH RES & DEV, INFECT DIS RES CTR, JAKARTA, INDONESIA. PROV HLTH SERV, PONTIANAK, W KALIMANTAN, INDONESIA. ABBOTT LABS, SINGAPORE, SINGAPORE. USN, INST MED RES, BETHESDA, MD 20852 USA. RP Corwin, A (reprint author), USN, MED RES UNIT 2, JAKARTA, INDONESIA. NR 11 TC 21 Z9 22 U1 0 U2 1 PU AMER SOC TROP MED & HYGIENE PI MCLEAN PA 8000 WESTPARK DR, STE 130, MCLEAN, VA 22101 USA SN 0002-9637 J9 AM J TROP MED HYG JI Am. J. Trop. Med. Hyg. PD JUL PY 1997 VL 57 IS 1 BP 62 EP 65 PG 4 WC Public, Environmental & Occupational Health; Tropical Medicine SC Public, Environmental & Occupational Health; Tropical Medicine GA XM907 UT WOS:A1997XM90700012 PM 9242320 ER PT J AU Richards, AL Soeatmadji, DW Widodo, MA Sardjono, TW Yanuwiadi, B Hernowati, TE Baskoro, AD Roebiyoso Hakim, L Soendoro, M Rahardjo, E Putri, MP Saragih, JM Strickman, D Kelly, DJ Dasch, GA Olson, JG Church, CJ Corwin, AL AF Richards, AL Soeatmadji, DW Widodo, MA Sardjono, TW Yanuwiadi, B Hernowati, TE Baskoro, AD Roebiyoso Hakim, L Soendoro, M Rahardjo, E Putri, MP Saragih, JM Strickman, D Kelly, DJ Dasch, GA Olson, JG Church, CJ Corwin, AL TI Seroepidemiologic evidence for murine and scrub typhus in Malang, Indonesia SO AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE LA English DT Article ID EPIDEMIOLOGY; INFECTION AB Indonesian military personnel stationed in Malang, East Java were among troops deployed to central Cambodia as part of the United Nations' Transition Authority Cambodia peace-keeping operation in 1992. Predeployment blood samples obtained from a cohort of Indonesian soldiers indicated a high prevalence of antibodies to antigens of Rickettsia typhi or Orientia (formerly Rickettsia) tsutsugamushi, the etiologic agents for murine and scrub typhus, respectively. To evaluate the potential risk of these rickettsial diseases in the Malang area, a subsequent seroepidemiologic survey was conducted. This study involved civilian personnel residing within one of three Malang kelurahans (neighborhoods) representing urban, suburban, and rural communities. The heads-of-households from 197 homes completed a detailed epidemiologic survey. In addition, blood samples were collected from 464 individuals residing within the households surveyed. Examination of civilian blood samples disclosed that 34.7% and 1.3% of the study participants were seroreactive to R. typhi and O. tsutsugamushi, respectively. These results were similar to those obtained earlier from the military samples. In addition, assessment of 78 blood samples obtained from peridomestic rodents trapped from within or near the households surveyed showed that 28 were reactive to R. typhi antigens and four were reactive to O. tsutsugamushi antigens. These data indicate that military and civilian personnel living in the Malang area of East Java are at risk of infection with rickettsiae that are antigenically indistinguishable from those that cause murine and scrub typhus. C1 MALANG MUNICIPAL HLTH OFF, MALANG, E JAVA, INDONESIA. USN, MED RES INST, VIRAL & RICKETTSIAL DIS PROGRAM, BETHESDA, MD 20889 USA. CTR DIS CONTROL & PREVENT, DIV VIRAL & RICKETTSIAL DIS, ATLANTA, GA 30333 USA. NATL INST HLTH RES & DEV, COMMUNICABLE DIS RES CTR, JAKARTA, INDONESIA. WALTER REED ARMY MED CTR, WALTER REED ARMY INST RES, WASHINGTON, DC 20307 USA. BRAWIJAYA UNIV, FAC MED, MALANG, INDONESIA. RP Richards, AL (reprint author), USN, MED RES UNIT 2, RICKETTSIAL DIS PROGRAM, BOX 3, APO AP 962508132, APO, INDONESIA. NR 31 TC 41 Z9 42 U1 0 U2 4 PU AMER SOC TROP MED & HYGIENE PI MCLEAN PA 8000 WESTPARK DR, STE 130, MCLEAN, VA 22101 USA SN 0002-9637 EI 1476-1645 J9 AM J TROP MED HYG JI Am. J. Trop. Med. Hyg. PD JUL PY 1997 VL 57 IS 1 BP 91 EP 95 PG 5 WC Public, Environmental & Occupational Health; Tropical Medicine SC Public, Environmental & Occupational Health; Tropical Medicine GA XM907 UT WOS:A1997XM90700018 PM 9242326 ER PT J AU Hazel, G Bucholtz, F Aggarwal, ID Nau, G Ewing, KJ AF Hazel, G Bucholtz, F Aggarwal, ID Nau, G Ewing, KJ TI Multivariate analysis of mid-IR FT-IR spectra of hydrocarbon-contaminated wet soils SO APPLIED SPECTROSCOPY LA English DT Article DE FT-IR reflectance spectroscopy; mid-IR spectroscopy; chemical detection; environmental cleanup; multivariate analysis; soil analysis ID REFLECTANCE AB This article describes a series of mid-IR FT-IR reflectance spectroscopy measurements of hydrocarbon-contaminated wet soils, The eventual goal of this work is the development of an analysis tool suitable for real-time in situ underground measurements where a suitable reference spectrum is not available, Multivariate analysis of the resulting spectral data indicates that the strongly varying wet soil matrix and the absence of a suitable reference spectrum in the field do not render this measurement technique unfeasible as a means of realizing remote in situ chemical detection in wet soils, It was also observed that simultaneous quantification of moisture content and identification of soil composition may be achieved, These results have important applications to in situ site characterization for environmental cleanup and soil characterization for construction planning. C1 USN,RES LAB,DIV OPT SCI,WASHINGTON,DC 20375. UNIV RES FDN,GREENBELT,MD 20770. NR 7 TC 20 Z9 21 U1 0 U2 0 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA 201B BROADWAY ST, FREDERICK, MD 21701 SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD JUL PY 1997 VL 51 IS 7 BP 984 EP 989 DI 10.1366/0003702971941359 PG 6 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA XP068 UT WOS:A1997XP06800012 ER PT J AU Schuman, JS Horwitz, B Choplin, NT David, R Albracht, D Chen, KK Gross, R Sloan, F Wilensky, J Katz, LJ Barnebey, H Jones, R Atlas, W Labarta, L Silverstone, D Zimmerman, T Klemperer, I Craven, ER Lamping, K Perell, HF Sturm, R Tortora, CM Hersh, S Levy, NS Rotberg, MH Terry, S Batoosingh, AL Drain, C Kelley, E Walt, JG AF Schuman, JS Horwitz, B Choplin, NT David, R Albracht, D Chen, KK Gross, R Sloan, F Wilensky, J Katz, LJ Barnebey, H Jones, R Atlas, W Labarta, L Silverstone, D Zimmerman, T Klemperer, I Craven, ER Lamping, K Perell, HF Sturm, R Tortora, CM Hersh, S Levy, NS Rotberg, MH Terry, S Batoosingh, AL Drain, C Kelley, E Walt, JG TI A 1-year study of brimonidine twice daily in glaucoma and ocular hypertension - A controlled, randomized, multicenter clinical trial SO ARCHIVES OF OPHTHALMOLOGY LA English DT Article; Proceedings Paper CT 67th Annual Meeting of the Association-for-Research-in-Vision-and-Ophthalmology CY APR 21-26, 1996 CL FT LAUDERDALE, FL SP Assoc Res Vis & Ophthalmol ID 1-PERCENT APRACLONIDINE; LASER TRABECULOPLASTY; INTRAOCULAR-PRESSURE; EFFICACY; THERAPY; TIMOLOL AB Objective: Brimonidine tartrate is a highly selective alpha(2)-agonist. This study investigates the safety and efficacy of 0.2% brimonidine administered twice daily for 1 year in patients with glaucoma or ocular hypertension. Methods: The study design was a multicenter, double-masked, randomized, parallel-group, active-controlled comparison clinical trial. Subjects instilled 0.2% brimonidine or 0.5% timolol maleate twice daily for 12 months. Subjects were examined at baseline, week 1, and months 1, 2, 3, 6, 9, and 12. A subset of subjects was examined at week 2. Results: Of 443 subjects enrolled in this study, 374 met the entry criteria; 186 received brimonidine and 188 received timolol. Brimonidine-treated subjects showed an overall mean peak reduction in intraocular pressure (IOP) of 6.5 mm Hg; timolol-treated subjects had a mean peak reduction in IOP of 6.1 mm Hg. Brimonidine lowered mean peak IOP significantly more than timolol at week 2 and month 3 (P<.03); no significant difference was observed between the groups for this variable at other visits throughout the 1-year course of:he study. No evidence of tachyphylaxis was seen in either group. Allergy was seen in 9% of subjects treated with brimonidine. Dry mouth was more common in the brimonidine-treated group than in the timolol-treated group (33.0% vs 19.4%), but complaints of burning and stinging were more common in the timolol-treated group (41.9%) than in the brimonidine-treated patients (28.1%). Headache, fatigue, and drowsiness were similar in the 2 groups. In general, the tolerance to medication was acceptable. Conclusions: Brimonidine is safe and effective in lowering IOP in glaucomatous eyes. Brimonidine provides a sustained long-term ocular hypotensive effect, is well tolerated, and has a low rate of allergic response. C1 TUFTS UNIV,SCH MED,NEW ENGLAND EYE CTR,BOSTON,MA 02111. USN,MED CTR,SAN DIEGO,CA 92152. ALLERGAN PHARMACEUT INC,IRVINE,CA 92715. BAYLOR COLL MED,HOUSTON,TX 77030. UNIV ILLINOIS,CHICAGO,IL. THOMAS JEFFERSON UNIV,WILLS EYE HOSP,PHILADELPHIA,PA 19107. UNIV LOUISVILLE,LOUISVILLE,KY 40292. BEN GURION UNIV NEGEV,IL-84105 BEER SHEVA,ISRAEL. RI Schuman, Joel/K-7304-2012 OI Schuman, Joel/0000-0002-8885-3766 NR 25 TC 123 Z9 128 U1 0 U2 5 PU AMER MEDICAL ASSOC PI CHICAGO PA 515 N STATE ST, CHICAGO, IL 60610 SN 0003-9950 J9 ARCH OPHTHALMOL-CHIC JI Arch. Ophthalmol. PD JUL PY 1997 VL 115 IS 7 BP 847 EP 852 PG 6 WC Ophthalmology SC Ophthalmology GA XK907 UT WOS:A1997XK90700002 PM 9230823 ER PT J AU Hilton, JL AF Hilton, JL TI The mass of the asteroid 15 Eunomia from observations of 1313 Berna and 1284 Latvia SO ASTRONOMICAL JOURNAL LA English DT Article AB The mass of the asteroid 15 Eunomia was determined from its perturbations of 1313 Berna and 1284 Latvia. The perturbation of Berna gives a mass for Eunomia of (4.2 +/- 1.1) x 10(-12) M.. The perturbation of Latvia gives an upper bound on the mass for Eunomia of 8 X 10(-12) M.. The mass determined using Berna gives a density of only 0.79 +/- 0.21 g cm(-3) assuming that Eunomia is a homogeneous sphere with a diameter of 272 km. However, Eunomia is not spherical; hence, its volume is very poorly known. Since a sphere has the highest volume to mean projected area ratio of any body the density of Eunomia may be much higher than indicated. Radar range observations will determine the position of the perturbed asteroid to a higher precision than the uncertainty in the current ephemerides. The estimated reduction in the uncertainty for the mass of Eunomia from a single ideal radar time delay measurement of Berna is a factor of 2. This reduction in the uncertainty makes radar ranges the best way to reduce the uncertainty in the mass of Eunomia. Both Latvia and Berna will be in position to be observed by the Arecibo radio telescope at opposition during 1998 and 2000. RP Hilton, JL (reprint author), USN OBSERV,3450 MASSACHUSETTS AVE NW,WASHINGTON,DC 20392, USA. NR 19 TC 14 Z9 14 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0004-6256 J9 ASTRON J JI Astron. J. PD JUL PY 1997 VL 114 IS 1 BP 402 EP 408 DI 10.1086/118484 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XH226 UT WOS:A1997XH22600039 ER PT J AU Young, PR Mason, HE Keenan, FP Widing, KG AF Young, PR Mason, HE Keenan, FP Widing, KG TI The Ar/Ca relative abundance in solar coronal plasma SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE sun, abundances; sun, corona; sun, UV radiation ID ELECTRON-IMPACT EXCITATION; ELEMENT ABUNDANCES; RATE COEFFICIENTS; PHOTOSPHERIC ABUNDANCES; COLLISION STRENGTHS; ATOMIC DATA; AR-XIV; FLARE; SPECTRUM; ARGON AB The relative abundances of elements with low and high first ionisation potentials (FIP) is a subject of much recent debate. In situ measurements of the solar wind reveal a clear pattern of low FIP enhancement that has been followed up with various spectroscopic measurements of the solar corona. Argon is unique amongst the more abundant high FIP elements in retaining several of its electrons at the high temperatures seen in flares. This allows emission lines of different ions to be compared with more confidence than for, say, hydrogenlike high FIP ions such as O VIII and Ne X. In this paper we look at emission lines of the boron-like ion Ar XIV; in particular, the optical line at 4412 Angstrom, seen in eclipse observations, is compared to the Ca XIII 4086 Angstrom and Ca XV 5445 Angstrom & 5694 Angstrom lines to yield an Ar/Ca abundance of 0.85 +/- 0.20. In the extreme ultra-violet (EUV), the Ar XIV lines at 187.94 Angstrom and 194.41 Angstrom can be compared with Ca XIV 193.87 Angstrom-flare data from Skylab giving values of 1.10 +/- 0.25 and 0.55 +/- 0.21. Analysis of previous work indicates a photospheric Ar/Ca abundance of 1.31 +/- 0.30, hence supporting the conclusion that elements with high FIP have lower coronal abundances. C1 QUEENS UNIV BELFAST, DEPT PURE & APPL PHYS, BELFAST BT7 1NN, ANTRIM, NORTH IRELAND. USN, RES LAB, EO HULBURT CTR SPACE RES, WASHINGTON, DC 20375 USA. RP Young, PR (reprint author), UNIV CAMBRIDGE, DEPT APPL MATH & THEORET PHYS, SILVER ST, CAMBRIDGE CB3 9EW, ENGLAND. NR 36 TC 18 Z9 18 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD JUL PY 1997 VL 323 IS 1 BP 243 EP 249 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XJ141 UT WOS:A1997XJ14100044 ER PT J AU Kovalevsky, J Lindegren, L Perryman, MAC Hemenway, PD Johnston, KJ Kislyuk, VS Lestrade, JF Morrison, LV Platais, I Roser, S Schilbach, E Tucholke, HJ deVegt, C Vondrak, J Arias, F Gontier, AM Arenou, F Brosche, P Florkowski, DR Garrington, ST Preston, RA Ron, C Rybka, SP Scholz, RD Zacharias, N AF Kovalevsky, J Lindegren, L Perryman, MAC Hemenway, PD Johnston, KJ Kislyuk, VS Lestrade, JF Morrison, LV Platais, I Roser, S Schilbach, E Tucholke, HJ deVegt, C Vondrak, J Arias, F Gontier, AM Arenou, F Brosche, P Florkowski, DR Garrington, ST Preston, RA Ron, C Rybka, SP Scholz, RD Zacharias, N TI The Hipparcos Catalogue as a realisation of the extragalactic reference system SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE astrometry; catalogs; reference systems ID EARTH ORIENTATION PARAMETERS; REFERENCE FRAME; REDUCTION SOFTWARE; STARS; ASTROMETRY; PERFORMANCE; CONSORTIUM; POSITIONS; ROTATION; PROGRAM AB The paper describes the methods and observations by which the Hipparcos Catalogue was linked to the International Celestial Reference System (ICRS). The contributions of several groups represented in the authorship of this paper, using a variety of techniques, were synthesised in order to determine the global orientation and rotation (spin) of the coordinate frame defined by the Hipparcos data with respect to extragalactic sources. The following link techniques were used: interferometric observations of radio stars by VLBI networks, MERLIN and VLA; observations of quasars relative to Hipparcos stars by means of CCDs and photographic plates. and by the Hubble Space Telescope photographic programmes to determine stellar proper motions with respect to extragalactic objects (Bonn, Kiev, Lick, Potsdam, Yale/San Juan); and comparison of Earth orientation parameters obtained by VLBI and by ground-based optical observations of Hipparcos stars. Although vastly different in terms of instruments, observational methods and objects involved, the various techniques generally agree to within 10 mas (milliarcsec) in the orientation and 1 mas/yr in the spin of the system. Two different numerical methods are described for the systematic comparison and synthesis of the link observations. The methods give very similar solutions, and a mean value was adopted for the definition of the system of positions and proper motions in the Hipparcos Catalogue. As a result, the coordinate axes defined by the published catalogue are believed to be aligned with the extragalactic radio frame to within +/- 0.6 mas at the epoch 1991.25, and non-rotating with respect to distant extragalactic objects to within +/- 0.25 mas/yr. C1 LUND OBSERV, S-22100 LUND, SWEDEN. EUROPEAN SPACE TECHNOL CTR, EUROPEAN SPACE AGCY, DIV ASTROPHYS, NL-2200 AG NOORDWIJK, NETHERLANDS. UNIV TEXAS, DEPT ASTRON, AUSTIN, TX 78712 USA. USN OBSERV, WASHINGTON, DC 20392 USA. UKRAINIAN ACAD SCI, MAIN ASTRON OBSERV, UA-252127 KIEV, UKRAINE. OBSERV PARIS, MEUDON SECT, F-92195 MEUDON, FRANCE. ROYAL GREENWICH OBSERV, CAMBRIDGE CB3 0EZ, ENGLAND. YALE UNIV OBSERV, NEW HAVEN, CT 06520 USA. ASTRON RECH INST, D-69120 HEIDELBERG, GERMANY. UNIV POTSDAM, WIP, D-14482 POTSDAM, GERMANY. UNIV STERNWARTE, D-53121 BONN, GERMANY. HAMBURGER STERNWARTE, D-21029 HAMBURG, GERMANY. ACAD SCI CZECH REPUBL, INST ASTRON, CR-14131 PRAGUE 4, CZECH REPUBLIC. ASTRON OBSERV, RA-1900 LA PLATA, ARGENTINA. OBSERV PARIS, IERS, F-75014 PARIS, FRANCE. UNIV MANCHESTER, NUFFIELD RADIO ASTRON LABS, JODRELL BANK, MACCLESFIELD SK11 9DL, CHESHIRE, ENGLAND. CALTECH, JET PROP LAB, PASADENA, CA 91109 USA. RP Kovalevsky, J (reprint author), OBSERV COTE AZUR, CERGA, AV COPERNIE, F-06130 GRASSE, FRANCE. RI Ron, Cyril/G-9038-2014; Vondrak, Jan/G-9057-2014; Arenou, Frederic/B-1846-2014; OI Arenou, Frederic/0000-0003-2837-3899; Perryman, Michael/0000-0002-3953-4750 NR 47 TC 109 Z9 120 U1 0 U2 3 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 1432-0746 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD JUL PY 1997 VL 323 IS 2 BP 620 EP 633 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XL461 UT WOS:A1997XL46100034 ER PT J AU Skibo, JG Dermer, CD Schlickeiser, R AF Skibo, JG Dermer, CD Schlickeiser, R TI The beaming pattern of Doppler-boosted thermal annihilation radiation: Application to MeV blazars SO ASTROPHYSICAL JOURNAL LA English DT Article DE distance scale; galaxies, active; gamma rays, theory; radiation mechanisms, nonthermal ID GAMMA-RAY EMISSION; ACTIVE GALACTIC NUCLEI; RADIO-SOURCES; SPECTRUM; COMPTEL; JET AB The beaming pattern of thermal annihilation radiation is broader than the beaming pattern produced by isotropic nonthermal electrons and positrons in the jets of radio-emitting active galactic nuclei that Compton scatter photons from an external isotropic radiation field. Thus, blueshifted thermal annihilation radiation can provide the dominant contribution to the high-energy radiation spectrum at observing angles theta greater than or similar to 1/Gamma, where Gamma is the bulk Lorentz factor of the outflowing plasma. This effect may account for the spectral features of MeV blazars discovered with the Compton Telescope on the Compton Gamma Ray Observatory. Coordinated gamma-ray observations of annihilation line radiation to infer Doppler factors and VLBI radio observations to measure transverse angular speeds of out-flowing plasma blobs can be used to determine the Hubble constant. C1 MAX PLANCK INST RADIOASTRON,D-53010 BONN,GERMANY. RP Skibo, JG (reprint author), USN,RES LAB,EO HULBURT CTR SPACE RES,CODE 7653,WASHINGTON,DC 20375, USA. NR 35 TC 13 Z9 14 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUL 1 PY 1997 VL 483 IS 1 BP 56 EP 61 DI 10.1086/304227 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XJ167 UT WOS:A1997XJ16700006 ER PT J AU Satyapal, S Watson, DM Pipher, JL Forrest, WJ Greenhouse, MA Smith, HA Fischer, J Woodward, CE AF Satyapal, S Watson, DM Pipher, JL Forrest, WJ Greenhouse, MA Smith, HA Fischer, J Woodward, CE TI The intrinsic properties of the stellar clusters in the M82 starburst complex: Propagating star formation? SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies evolution; galaxies, individual (M82); galaxies nuclei; galaxies, starburst; galaxies, star clusters; infrared, galaxies ID INITIAL MASS FUNCTION; INFRARED PHOTOMETRY; GALAXY M82; NUCLEUS; EMISSION; CO AB Near-Infrared spectroscopy combined with high spatial resolution imaging have been used in this work to probe the central 500 pc of M82. Imaging observations in the 2.36 mu m CO band head are added to our previously published near-infrared hydrogen recombination line imaging, near-infrared broadband imaging, and 3.29 mu m dust feature imaging observations, in order to study the nature of the starburst stellar population. A starburst model is constructed and compared with the observations of the stellar clusters in the starburst complex. Our analysis implies that the typical age for the starburst clusters is 10(7) yr. In addition, our high spatial resolution observations indicate that there is an age dispersion within the starburst complex that is correlated with projected distance from the center of the galaxy. The inferred age dispersion is 6 x 10(6) yr. If the starburst in M82 is propagating outward from the center, this age dispersion corresponds to a velocity of propagation, originating in the center, of similar to 50 km s(-1). Our quantitative analysis also reveals that a Salpeter initial mass function, extending from 0.1 to 100 M-., can fit the observed properties of M82 without using up more than 30% of the total dynamical mass in the starburst. C1 UNIV ROCHESTER,DEPT PHYS & ASTRON,ROCHESTER,NY 14627. HARVARD SMITHSONIAN CTR ASTROPHYS,CAMBRIDGE,MA 02138. USN,RES LAB,REMOTE SENSING DIV,WASHINGTON,DC 20375. UNIV WYOMING,DEPT PHYS & ASTRON,LARAMIE,WY 82071. RP Satyapal, S (reprint author), NASA,GODDARD SPACE FLIGHT CTR,CODE 685,GREENBELT,MD 20771, USA. NR 46 TC 100 Z9 100 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUL 1 PY 1997 VL 483 IS 1 BP 148 EP 160 DI 10.1086/304214 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XJ167 UT WOS:A1997XJ16700016 ER PT J AU VonMontigny, C Aller, H Aller, M Bruhweiler, F Collmar, W Courvoisier, TJL Edwards, PG Fichtel, CE Fruscione, A Ghisellini, G Hartman, RC Johnson, WN Kafatos, M Kii, T Kniffen, DA Lichti, GG Makino, F Mannheim, K Marscher, AP McBreen, B McHardy, I Pesce, JE Pohl, M Ramos, E Reich, W Robson, EI Sasaki, K Terasranta, H Tornikoski, M Urry, CM Valtaoja, E Wagner, S Weekes, T AF VonMontigny, C Aller, H Aller, M Bruhweiler, F Collmar, W Courvoisier, TJL Edwards, PG Fichtel, CE Fruscione, A Ghisellini, G Hartman, RC Johnson, WN Kafatos, M Kii, T Kniffen, DA Lichti, GG Makino, F Mannheim, K Marscher, AP McBreen, B McHardy, I Pesce, JE Pohl, M Ramos, E Reich, W Robson, EI Sasaki, K Terasranta, H Tornikoski, M Urry, CM Valtaoja, E Wagner, S Weekes, T TI Multiwavelength observations of 3C 273 in 1993-1995 SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays, observations; quasars, individual (3C 273); radiation mechanisms, nonthermal ID GAMMA-RAY EMISSION; EXTRAGALACTIC RADIO-SOURCES; QUASARS 3C-273; COS-B; RADIATION; JET; TELESCOPE; BLAZARS; 3C273; COMPTONIZATION AB We present the results of the multiwavelength campaigns on 3C 273 in 1993-1995. During the observations in late 1993, this quasar showed an increase of its flux for energies greater than or equal to 100 MeV from about 2.1 x 10(-7) photons cm(-2) s(-1) to approximately 5.6 x 10(-7) photons cm(-2) s(-1) during a radio outburst at 14.5, 22, and 37 GHz. However, no one-to-one correlation of the gamma-ray radiation with any frequency could be found. The photon spectral index of the high-energy spectrum changed from Gamma(gamma) = (3.20 +/- 0.54) to Gamma(gamma) = (2.20 +/- 0.22) in the sense that the spectrum flattened when the gamma-ray flux increased. Fits of the three most prominent models (synchrotron self-Comptonization, external inverse Comptonization, and the proton-initiated cascade model) for the explanation of the high gamma-ray emission of active galactic nuclei were performed to the multiwavelength spectrum of 3C 273. All three models are able to represent the basic features of the multiwavelength spectrum. Although there are some differences, the data are still not decisive enough to discriminate between the models. C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. UNIV MICHIGAN,DEPT ASTRON,ANN ARBOR,MI 48109. CATHOLIC UNIV AMER,DEPT PHYS,WASHINGTON,DC 20064. MAX PLANCK INST EXTRATERR PHYS,D-85740 GARCHING,GERMANY. INTEGRAL SCI DATA CTR,CH-1290 SAUVERNY,SWITZERLAND. INST SPACE & ASTRONAUT SCI,SAGAMIHARA,KANAGAWA 229,JAPAN. HARVARD SMITHSONIAN CTR ASTROPHYS,CAMBRIDGE,MA 02138. OSSERVATORIO BRERA MERATE,MERATE,ITALY. USN,RES LAB,EO HULBURT CTR SPACE RES,WASHINGTON,DC 20375. GEORGE MASON UNIV,CSI,CTR EARTH OBSERV & SPACE RES,FAIRFAX,VA 22030. HAMPDEN SYDNEY COLL,HAMPDEN SYDNEY,VA 23943. UNIV STERNWARTE,D-37803 GOTTINGEN,GERMANY. BOSTON UNIV,DEPT ASTRON,BOSTON,MA 02215. UNIV COLL,DEPT PHYS,DUBLIN 4,IRELAND. UNIV SOUTHAMPTON,DEPT PHYS,SOUTHAMPTON SO9 5NH,HANTS,ENGLAND. SPACE TELESCOPE SCI INST,BALTIMORE,MD 21218. MAX PLANCK INST RADIOASTRON,BONN,GERMANY. JOINT ASTRON CTR,HILO,HI 96720. METSAHOVI RADIO RES STN,FIN-02540 KYLMALA,FINLAND. UNIV TURKU,TUORLA OBSERV,SF-21500 PIIKKIO,FINLAND. HARVARD SMITHSONIAN CTR ASTROPHYS,WHIPPE OBSERV,AMADO,AZ 85645. LANDESSTERNWARTE HEIDELBERG KONIGSTUHL,D-69117 HEIDELBERG,GERMANY. RI Mannheim, Karl/F-6705-2012; Urry, Claudia/G-7381-2011; Johnson, Neil/G-3309-2014 OI Urry, Claudia/0000-0002-0745-9792; NR 73 TC 65 Z9 65 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUL 1 PY 1997 VL 483 IS 1 BP 161 EP 177 DI 10.1086/304219 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XJ167 UT WOS:A1997XJ16700017 ER PT J AU Kravtsov, AV Klypin, AA Khokhlov, AM AF Kravtsov, AV Klypin, AA Khokhlov, AM TI Adaptive refinement tree: A new high-resolution N-body code for cosmological simulations SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE methods, numerical; cosmology, theory; dark matter ID COLD DARK MATTER; MESH REFINEMENT; GALACTIC HALOES; UNIVERSE; HYDRODYNAMICS; ALGORITHM; COLLAPSE; SOLVER AB We present a new high-resolution N-body algorithm for cosmological simulations. The algorithm employs a traditional particle-mesh technique on a cubic grid and successive multilevel relaxations on the finer meshes, introduced recursively in a fully adaptive manner in the regions where the density exceeds a predefined threshold. The mesh is generated to effectively match an arbitrary geometry of the underlying density field-a property particularly important for cosmological simulations. In a simulation the mesh structure is not created at every time step but is properly adjusted to the evolving particle distribution. The algorithm is fast and effectively parallel: the gravitational relaxation solver is approximately half as fast as the fast Fourier transform solver on the same number of mesh cells. The required CPU time scales with the number of cells, N-c, as similar to 0(N-c). The code allows us to improve considerably the spatial resolution of the particle-mesh code without loss in mass resolution. We present a detailed description of the methodology, implementation, and tests of the code. We further use the code to study the structure of dark matter halos in high-resolution (similar to 2 h(-1) kpc) simulations of standard CDM (Omega = 1, h = 0.5, sigma(g) = 0.63) and Lambda CDM (Omega(A) = 1 - Omega(0) = 0.7, h = 0.7, sigma(8) = 1.0) models. We find that halo density profiles in both CDM and Lambda CDM models are well fitted by the analytical model presented recently by Navarro et al., which predicts a singular [rho(r) proportional to r(-1)] behavior of the halo density profiles at small radii. We therefore conclude that halos formed in the ACDM model have structure similar to that of CDM halos and thus cannot explain the dynamics of the central parts of dwarf spiral galaxies, as inferred from the galaxies' rotation curves. C1 USN, RES LAB, COMPUTAT PHYS & FLUID DYNAM LAB, WASHINGTON, DC 20375 USA. RP NEW MEXICO STATE UNIV, DEPT ASTRON, DEPT 4500, BOX 30001, LAS CRUCES, NM 88003 USA. NR 56 TC 438 Z9 441 U1 0 U2 6 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0067-0049 EI 1538-4365 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD JUL PY 1997 VL 111 IS 1 BP 73 EP 94 DI 10.1086/313015 PG 22 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XL757 UT WOS:A1997XL75700002 ER PT J AU Fey, AL Charlot, P AF Fey, AL Charlot, P TI VLBA observations of radio reference frame sources .2. Astrometric suitability based on observed structure SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE quasars, general; radio continuum, galaxies; surveys ID INTERFEROMETRY AB We present simultaneous dual-frequency Very Long Baseline Array 2 and 8 GHz observations of 133 of the 560 extragalactic sources for which positions were reported by Johnston et al. These observations represent the second in a series of observations intended to image the entire set of sources presented by Johnston et al. and, together with previously reported observations, bring the total number of sources observed so far to 169. We use the data to quantify the magnitude of the expected effect of intrinsic source structure on astrometric bandwidth synthesis VLBI observations. We also define a source ''structure index,'' which can be used as an estimate of the astrometric quality of the sources. C1 OBSERV PARIS,CNRS,URA 1125,F-75014 PARIS,FRANCE. RP Fey, AL (reprint author), USN OBSERV,CODE EO,3450 MASSACHUSETTS AVE NW,WASHINGTON,DC 20392, USA. NR 13 TC 130 Z9 134 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD JUL PY 1997 VL 111 IS 1 BP 95 EP 142 DI 10.1086/313017 PG 48 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XL757 UT WOS:A1997XL75700003 ER PT J AU Douglass, GG Hindsley, RB Worley, CE AF Douglass, GG Hindsley, RB Worley, CE TI Speckle interferometry at the US Naval Observatory .1. SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE binaries, visual; surveys; techniques, interferometric ID BINARY STARS AB We present speckle interferometer measurements of 467 binary stars taken at the US Naval Observatory in Washington, DC, using the 66 cm refractor, from 1990 October through 1992 December. The observing program is designed to provide high-quality observations of binaries in the 0.'' 3-3.'' 5 range of separations and as faint as 10.0 mag. More than 8000 measurements have been made to date, of which we report the results for 2329. Not only is it our intent to provide accurate data for interesting binary stars, but also, by careful calibration, to firmly relate the ''classical'' astrometry of binary stars to that being obtained today by speckle and that which will soon be obtained by other modern techniques such as long-baseline optical interferometry. RP Douglass, GG (reprint author), USN OBSERV,WASHINGTON,DC 20392, USA. NR 10 TC 26 Z9 26 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD JUL PY 1997 VL 111 IS 1 BP 289 EP 334 DI 10.1086/313018 PG 46 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XL757 UT WOS:A1997XL75700010 ER PT J AU Smith, DR Geer, IW McManus, DE AF Smith, DR Geer, IW McManus, DE TI The Maury project: An educational partnership for oceanography SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article AB The education program of the American Meteorological Society established a unique partnership in 1994 with the United States Naval Academy and oceanographic agencies of both the National Oceanic and Atmospheric Administration and the U.S. Navy. This partnership, called the Maury Project, was formed to promote the study of the physical foundations of oceanography for precollege teachers. The primary activity of the Maury Project has been 2-week summer programs for teachers hosted by the Oceanography Department at the Naval Academy. In addition, a variety of educational materials has been developed to provide participating teachers with topics to conduct workshops for their colleagues in their home states. In the 2 years since the first Maury Project summer workshop, Maury peer trainers have conducted approximately 200 workshops reaching some 3600 teachers at a variety of conferences and other in-service training sessions. This paper focuses on the partnership aspect of the Maury Project. The combination of a variety of organizations involved in both the operational and research activities of physical oceanography provides a network of individuals and resources that can greatly enhance teaching about this discipline. The overall characteristics of the program are described and major outcomes from the first 3 years are outlined. C1 AMER METEOROL SOC,EDUC PROGRAM,WASHINGTON,DC. RP Smith, DR (reprint author), USN ACAD,DEPT OCEANOG,ANNAPOLIS,MD 21402, USA. NR 4 TC 7 Z9 7 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD JUL PY 1997 VL 78 IS 7 BP 1497 EP 1502 PG 6 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA XP114 UT WOS:A1997XP11400007 ER PT J AU Wu, SJL Hanson, B Paxton, H Nisalak, A Vaughn, DW Rossi, C Henchal, EA Porter, ER Watts, DM Hayes, CG AF Wu, SJL Hanson, B Paxton, H Nisalak, A Vaughn, DW Rossi, C Henchal, EA Porter, ER Watts, DM Hayes, CG TI Evaluation of a dipstick enzyme-linked immunosorbent assay for detection of antibodies to dengue virus SO CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY LA English DT Article ID JAPANESE ENCEPHALITIS; HEMORRHAGIC-FEVER; IMMUNOASSAY; ELISA; INFECTIONS; IGM; DIAGNOSIS AB Accurate serological confirmation of dengue (DEN) infection is difficult, because simple reliable assays for the detection of DEN antibodies are not available, To address this problem, a dipstick enzyme-linked immunosorbent assay (ELISA) was evaluated, The dipstick contained dots of serially diluted DEN 2 antigen, To detect immunoglobulin G (IgG), the dipstick was processed through four reaction cuvettes containing test serum, enhancer, enzyme-conjugated anti-human IgG and IgM antibody, and substrate, Total assay time was 45 min, To detect IgM, the serum was passed through a protein G device to remove Ipc, The dipstick was then processed as before, except that the incubation times were longer and enzyme-conjugated anti-human IgM was used, The total assay time was 3 h, The dipstick ELISA results were compared with results from microplate ELISA. The IgG dipstick ELISA showed a sensitivity of 95.2% and a specificity of 100% compared to an IgG microplate ELISA with serum samples from 125 individuals living in an area in which DEN is endemic, In tests with 75 serum samples from patients with clinically suspected acute DEN infections, the IgM dipstick ELISA showed a sensitivity of 97.9% and specificity of 100% compared to those of an IgM antibody capture microplate ELISA, These results shelved that the dipstick ELISA was a sensitive and specific test for the detection of either DEN IgM or IgG in human serum, The dipstick ELISA was also shown to be useful for detecting seroconversions to DEN IgM or IgG in paired serum samples from 20 patients with virus isolation-confirmed acute DEN infections. C1 INTEGRATED DIAGNOST INC,BALTIMORE,MD 21227. ARMED FORCES RES INST MED SCI,DEPT VIROL,BANGKOK 10400,THAILAND. USA,MED RES INST INFECT DIS,DIAGNOST SYST DIV,FT DETRICK,MD 21702. NAVAL MED RES INST DETACHMENT,LIMA,PERU. RP Wu, SJL (reprint author), USN,MED RES INST,DEPT INFECT DIS,CODE 41,8901 WISCONSIN AVE,BETHESDA,MD 20889, USA. NR 28 TC 29 Z9 29 U1 0 U2 1 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 SN 1071-412X J9 CLIN DIAGN LAB IMMUN JI Clin. Diagn. Lab. Immunol. PD JUL PY 1997 VL 4 IS 4 BP 452 EP 457 PG 6 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA XH998 UT WOS:A1997XH99800011 PM 9220163 ER PT J AU Gillingham, BL Wright, JG AF Gillingham, BL Wright, JG TI Convergent dislocation of the elbow SO CLINICAL ORTHOPAEDICS AND RELATED RESEARCH LA English DT Article AB Proximal radioulnar translocation is an extremely rare injury. Only seven cases have been reported previously, The authors report the case of a 6-year-old girl whose translocation was undiagnosed for more than 2 weeks, Definitive treatment required open reduction and use of a radiocapitellar pin to stabilize the proximal radius, At the 2-year followup, the patient has no symptoms and has resumed full activity with nearly full range of motion, To ensure early diagnosis of rare types of elbow dislocations, it is important to recognize the lack of supination and disruption of the radiocapitellar relationship on radiographs. C1 USN,MED CTR,DEPT ORTHOPED,SAN DIEGO,CA 92134. USN,MED CTR,DEPT CLIN INVEST,SAN DIEGO,CA 92134. HOSP SICK CHILDREN,TORONTO,ON M5G 1X8,CANADA. NR 8 TC 4 Z9 4 U1 0 U2 0 PU LIPPINCOTT-RAVEN PUBL PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 SN 0009-921X J9 CLIN ORTHOP RELAT R JI Clin. Orthop. Rel. Res. PD JUL PY 1997 IS 340 BP 198 EP 201 PG 4 WC Orthopedics; Surgery SC Orthopedics; Surgery GA XJ873 UT WOS:A1997XJ87300025 PM 9224256 ER PT J AU Williams, BA Fleming, JW AF Williams, BA Fleming, JW TI Radical species profiles in low-pressure methane flames containing fuel nitrogen compounds SO COMBUSTION AND FLAME LA English DT Article ID SHOCK-TUBE; MECHANISM; KINETICS; ACETONITRILE; TEMPERATURE; COMBUSTION; OXIDATION; CHEMISTRY; NO2 AB Relative concentration profiles of CN, NH, NCO, NH2, and NO are recorded for a 10 torr, premixed CH4/O-2/Ar flame doped with the following compounds: 0.35% NH3, CH3NH2, and CH3CN, and 0.86% NO. Profiles were measured by laser-induced fluorescence and compared between the different dopants. The experimental data are compared to detailed kinetic calculations based on the Gas Research Institute mechanism 2.11 for the NH3 and NO dopants, with added submechanisms for CH3CH and CH3NH2. The kinetic model underpredicts the amount of CN and NCO formed from the ammonia dopant; if we postulate a reaction between CH3 and NH, these discrepancies are largely resolved. Comparison of CN and NCO profiles between the NO and NH, dopants indicates that HCN is the primary product of the CH + NO reaction. Extrapolation of measured rates for CH3CN destruction reactions to combustion temperatures predicts a rate of CH3CN removal which is far too slow. Previously published mechanisms for methylamine combustion overpredict the amount of NH2 produced, indicating that cleavage of the C-N bond is less likely in the initial attack than the kinetic mechanisms predict. We propose modifications to the CH3CN and CH3NH2 submechanisms which correct these deficiencies and lead to good agreement with the measured intermediate profiles for all dopants. (C) 1997 by The Combustion Institute. RP Williams, BA (reprint author), USN,RES LAB,DIV CHEM,WASHINGTON,DC 20375, USA. NR 30 TC 28 Z9 28 U1 0 U2 5 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD JUL PY 1997 VL 110 IS 1-2 BP 1 EP 13 DI 10.1016/S0010-2180(97)00063-1 PG 13 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA XF514 UT WOS:A1997XF51400001 ER PT J AU Waldron, A AF Waldron, A TI ''Eat people'' - A Chinese reckoning SO COMMENTARY LA English DT Article RP Waldron, A (reprint author), USN,WAR COLL,WASHINGTON,DC, USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER JEWISH COMMITTEE PI NEW YORK PA 165 E 56TH ST, NEW YORK, NY 10022 SN 0010-2601 J9 COMMENTARY JI Commentary PD JUL PY 1997 VL 104 IS 1 BP 28 EP 33 PG 6 WC Political Science; Social Issues SC Government & Law; Social Issues GA XF587 UT WOS:A1997XF58700028 ER PT J AU Lewis, T AF Lewis, T TI Emergent behavior, emergent profits SO COMPUTER LA English DT Article RP Lewis, T (reprint author), USN,POSTGRAD SCH,CODE CS,MONTEREY,CA 93943, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 SN 0018-9162 J9 COMPUTER JI Computer PD JUL PY 1997 VL 30 IS 7 BP 120 EP & PG 3 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA XH984 UT WOS:A1997XH98400024 ER PT J AU Kwon, YW Berner, JM AF Kwon, YW Berner, JM TI Matrix damage of fibrous composites: Effects of thermal residual stresses and layer sequences SO COMPUTERS & STRUCTURES LA English DT Article; Proceedings Paper CT 2nd International Conference on Computational Structures Technology CY AUG 30-SEP 01, 1994 CL ATHENS, GREECE SP Greek Assoc Comp Mech, Greek Minist Culture, Gen Secretariat Res & Technol Greece, Tourist Org Greece, Nato TU Athens, Univ Patras, Democritus Univ Thrace, Evgenidis Fdn, UNISYS Hellas ID STIFFNESS REDUCTION; CRACKING; GLASS; FIBER; FRACTURE AB A simplified micromechanics model and a damage evolution function are incorporated into a finite-element analysis program for laminated fibrous composite structures in order to investigate the effects of microscale damages on the structural response. The computer program can analyze both fiber failure and matrix cracking. However, the present study focuses on matrix cracking. In the present study, two kinds of problems are solved using the computer program. The first study is to investigate effects of contiguous stacking of 90 degrees layers in cross-ply composites on reduction of composite stiffness. The analyses show that more contiguous stacking of 90 degrees layers in cross-ply composites causes a greater stiffness reduction for the same amount of matrix cracking. The second study investigates the effect of thermal residual stresses on the composite stiffness reduction. The results show that the thermal residual stresses play an important role in matrix cracking of cross-ply, fibrous composites. (C) 1997 Civil-Comp Ltd and Elsevier Science Ltd. RP Kwon, YW (reprint author), USN,POSTGRAD SCH,DEPT MECH ENGN,MONTEREY,CA 93943, USA. NR 20 TC 22 Z9 22 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0045-7949 J9 COMPUT STRUCT JI Comput. Struct. PD JUL-AUG PY 1997 VL 64 IS 1-4 BP 375 EP 382 DI 10.1016/S0045-7949(96)00432-4 PG 8 WC Computer Science, Interdisciplinary Applications; Engineering, Civil SC Computer Science; Engineering GA XG831 UT WOS:A1997XG83100028 ER PT J AU Barton, O Reiss, R AF Barton, O Reiss, R TI Vibration of antisymmetric laminated plates using eigensensitivity analysis SO COMPUTERS & STRUCTURES LA English DT Article; Proceedings Paper CT 2nd International Conference on Computational Structures Technology CY AUG 30-SEP 01, 1994 CL ATHENS, GREECE SP Greek Assoc Comp Mech, Greek Minist Culture, Gen Secretariat Res & Technol Greece, Tourist Org Greece, Nato TU Athens, Univ Patras, Democritus Univ Thrace, Evgenidis Fdn, UNISYS Hellas AB Approximate closed-form expressions are developed to predict the vibration of rectangular angle-ply antisymmetric laminated composite plates. The set of partial differential equations is first represented in abstract form and then converted into discrete form using an Ritz approach. Sensitivity derivatives are determined which are used to provide a Maclaurin series representation of the laminate's frequency. A comparison of numerical results calculated for various boundary conditions using both the derived formula and the Rayleigh-Ritz method validates the accuracy of the approximate formula. (C) 1997 Published by Elsevier Science Ltd. RP Barton, O (reprint author), USN ACAD,121 BLAKE RD,ANNAPOLIS,MD 21402, USA. NR 12 TC 2 Z9 2 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0045-7949 J9 COMPUT STRUCT JI Comput. Struct. PD JUL-AUG PY 1997 VL 64 IS 1-4 BP 425 EP 439 DI 10.1016/S0045-7949(96)00416-6 PG 15 WC Computer Science, Interdisciplinary Applications; Engineering, Civil SC Computer Science; Engineering GA XG831 UT WOS:A1997XG83100032 ER PT J AU Leonard, JW Sun, Y Palo, PA AF Leonard, JW Sun, Y Palo, PA TI Time decrement simulation of expeditious oceanic cable-body installation SO COMPUTERS & STRUCTURES LA English DT Article; Proceedings Paper CT 2nd International Conference on Computational Structures Technology CY AUG 30-SEP 01, 1994 CL ATHENS, GREECE SP Greek Assoc Comp Mech, Greek Minist Culture, Gen Secretariat Res & Technol Greece, Tourist Org Greece, Nato TU Athens, Univ Patras, Democritus Univ Thrace, Evgenidis Fdn, UNISYS Hellas AB In the simulation of cable-body deployment problems, the final state, i.e. predetermined locations at ocean bottom, are more restrained than the initial state. Thus it was hypothesized that it is possible to reverse the time integration process, i.e. given desired coordinates, stresses and velocities in the final state, small steps backward in time can be taken and the values of all variables predicted needed to achieve that final state. Solving the cable governing equation backwards in time and space is mathematically ill-posed. The difficulties in obtaining stable time decrement solutions are described from both numerical and physical points of view. Several approaches are considered and described. Details are given for the most successful approach which defines a well-postulated conjugate problem whose solution is close to the solution of the original problem. Three illustrative examples of the deployment of cable-bodies from a surface vessel are given to demonstrate the validity of the method. (C) 1997 Civil-Comp Ltd and Elsevier Science Ltd. C1 USN,FACIL ENGN SERV CTR,OCEAN ENGN DIV,PORT HUENEME,CA 93043. RP Leonard, JW (reprint author), UNIV CONNECTICUT,DEPT CIVIL ENGN,STORRS,CT 06250, USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0045-7949 J9 COMPUT STRUCT JI Comput. Struct. PD JUL-AUG PY 1997 VL 64 IS 1-4 BP 453 EP 459 DI 10.1016/S0045-7949(96)00128-9 PG 7 WC Computer Science, Interdisciplinary Applications; Engineering, Civil SC Computer Science; Engineering GA XG831 UT WOS:A1997XG83100034 ER PT J AU McCafferty, E Natishan, PM Hubler, GK AF McCafferty, E Natishan, PM Hubler, GK TI Pitting behavior of aluminum ion implanted with nitrogen SO CORROSION LA English DT Article DE aluminum; dissolution; ion implantation; nitrogen; pitting corrosion; repassivation; sodium chloride; stainless steels; x-ray photoelectron spectroscopy ID RAY PHOTOELECTRON-SPECTROSCOPY; AUSTENITIC STAINLESS-STEEL; CORROSION BEHAVIOR; SURFACE ALLOYS; ANODIC-OXIDATION; XPS; MO; RESISTANCE; PASSIVITY; NITRIDE AB Ion implantation of approximate to 2 at9% N into aluminum increased the pitting potential in 0.1 M sodium chloride (NaCl) by an average of 0.35 V. Surface analysis by x-ray photoelectron spectroscopy (XPS) showed implanted nitrogen was present as several species: NH4+, NO or NH, (as a ligand), AIN, and weakly bound or interstitial nitrogen. With anodic polarization, there was an increase in the total amount of nitrogen in the near-surface region, a decrease in the relative amount of nitride, and an increase in the relative amount of NO or NH3. These changes resulted from migration of implanted nitrogen from the substrate into the near-surface region with partial conversion of the AIN species to NO or NH3. It was suggested that the effect of implanted nitrogen on pitting behavior of aluminum is similar to that in nitrogen-containing stainless steels (SS), where nitrogen at the metal surface inhibits the dissolution kinetics or aids the repassivation process in the pit by forming NH4+ ions that buffer the pit electrolyte. RP McCafferty, E (reprint author), USN,RES LAB,DEPT NAVY,4555 OVERLOOK AVE SW,WASHINGTON,DC 20375, USA. NR 43 TC 16 Z9 16 U1 0 U2 1 PU NATL ASSN CORROSION ENG PI HOUSTON PA 1440 SOUTH CREEK DRIVE, HOUSTON, TX 77084-4906 SN 0010-9312 J9 CORROSION JI Corrosion PD JUL PY 1997 VL 53 IS 7 BP 556 EP 561 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA XU788 UT WOS:A1997XU78800006 ER PT J AU Fox, NA Mary, S Davis, TJ Wang, WN May, PW Bewick, A Steeds, JW Butler, JE AF Fox, NA Mary, S Davis, TJ Wang, WN May, PW Bewick, A Steeds, JW Butler, JE TI Field-emission studies of boron-doped CVD diamond films following surface treatments SO DIAMOND AND RELATED MATERIALS LA English DT Article; Proceedings Paper CT DIAMOND 1996 Conference CY SEP 08-13, 1996 CL TOURS, FRANCE DE field-emission; CVD diamond; boron doping; surface treatment ID ELECTRON AB The electron emission from highly twinned, undoped Chemical Vapour Deposited (CVD) diamond thin films has been found to exhibit a stable voltage threshold of 15 V mu m(-1). In this study the same material has been boron-doped by ion-implantation at two different energy profiles. A number of surface treatments including, Excimer laser annealing, hydrogen passivation, argon/oxygen plasma etching and also coating with gold, were employed in an attempt to enhance the electron emission properties of the highly twinned surface. It has been found that these treatments tend to degrade the electron emission performance, promoting more surface damage and instability in the electron emission current. These results are compared against the emission performance of samples of high quality boron-doped material exhibiting both similar and dissimilar surface textures. (C) 1997 Elsevier Science S.A. C1 USN,RES LAB,WASHINGTON,DC 20375. RP Fox, NA (reprint author), UNIV BRISTOL,DIAMOND GRP,BRISTOL,AVON,ENGLAND. RI Butler, James/B-7965-2008 OI Butler, James/0000-0002-4794-7176 NR 10 TC 15 Z9 15 U1 1 U2 4 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-9635 J9 DIAM RELAT MATER JI Diam. Relat. Mat. PD JUL PY 1997 VL 6 IS 9 BP 1135 EP 1142 DI 10.1016/S0925-9635(97)00030-7 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA XR614 UT WOS:A1997XR61400009 ER PT J AU Battaile, CC Srolovitz, DJ Butler, JE AF Battaile, CC Srolovitz, DJ Butler, JE TI Morphologies of diamond films from atomic-scale simulations of chemical vapor deposition SO DIAMOND AND RELATED MATERIALS LA English DT Article DE computer simulation; diamond films; morphology; CVD ID CVD-GROWN DIAMOND; MOLECULAR-DYNAMICS; 113 FACETS; AB-INITIO; SURFACES; RECONSTRUCTION; HYDROGEN; C(100); CHEMISTRY; ACETYLENE AB The growth of {110}- and {111}-oriented diamond films under typical chemical vapor deposition (CVD) conditions was simulated on the atomic scale. The films are represented in three dimensions by diamond cubic crystal lattices, and thus the effects of surface atomic structure and him morphology are built into the model. The temporal evolution of the films during growth is accomplished by a kinetic Monte Carlo scheme parameterized by conventional surface chemical reaction-rate coefficients. Growth on {110}:H and {111}:H surfaces was simulated in atmospheres containing H, H-2, CH3 and various partial pressures of C2H2. Film growth rates and morphologies are found to depend strongly on the presence of C2H2 at the surface. Under typical growth conditions, film growth rates agree well with experiment and other modeling studies, and the film morphologies are atomically rough. However, growth of {110} and {111} films in C2H2-deficient environments is found to be controlled by the nucleation of diamond clusters on smooth faces, and growth rates are very low under these conditions. This is because the initiation of a monolayer on smooth {110} and {111} facets requires the bonding of two and three adsorbed C atoms, respectively. Since a single C2H2 molecule contributes two C atoms when it is chemisorbed, the presence of C2H2 is important to {110} and especially {111} growth. The {111} films grow by the flow of atomic-height steps at triangular islands on the surface and are atomically smooth when the partial pressure of C2H2 is very low. The {110} films grow by one-dimensional step flow in the atomic ''troughs'' of the {110}-terminated diamond cubic surface, and become corrugated into {111} microfacets. (C) 1997 Elsevier Science S.A. C1 UNIV MICHIGAN, ANN ARBOR, MI 48109 USA. USN, RES LAB, GAS SURFACE DYNAM SECT, WASHINGTON, DC 20375 USA. RI Butler, James/B-7965-2008 OI Butler, James/0000-0002-4794-7176 NR 42 TC 36 Z9 36 U1 2 U2 12 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-9635 EI 1879-0062 J9 DIAM RELAT MATER JI Diam. Relat. Mat. PD JUL PY 1997 VL 6 IS 9 BP 1198 EP 1206 DI 10.1016/S0925-9635(97)00046-0 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA XR614 UT WOS:A1997XR61400016 ER PT J AU Joyce, JA Link, RE AF Joyce, JA Link, RE TI Application of two parameter elastic-plastic fracture mechanics to analysis of structures SO ENGINEERING FRACTURE MECHANICS LA English DT Article AB J-integral resistance curves are developed for single edge bend [SE(B)] specimens of HY80 over a range of crack length ratios from 0.13 to 0.83. The wide range of constraint present over this range of crack length ratios results in J-integral resistance curves with nearly constant initiation toughnesses as measured by J(Ic), but with widely varying J-R curve slopes beyond J(Ic). A nearly linear relationship is shown to exist between the slope of the material J-resistance curve after 1 mm of crack extension and the Q parameter introduced by O'Dowd and Shih (Family of crack-tip fields characterized by a triaxiality parameter: Part I - Structure of fields. Journal of Mechanics and Physics of Solids, 1991, 39(8), 989-1015) to quantify elastic-plastic constraint. The constancy of J(Ic) and the linear dependence of the tearing resistance on Q is used to develop an interpolation scheme to evaluate the J-integral resistance curve applicable to a specific structural application when the Q parameter can be estimated for the flaw geometry and loading present in the application. Published by Elsevier Science Ltd. RP Joyce, JA (reprint author), USN ACAD,DEPT MECH ENGN,590 HOLLOWAY RD,ANNAPOLIS,MD 21402, USA. NR 16 TC 65 Z9 66 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0013-7944 J9 ENG FRACT MECH JI Eng. Fract. Mech. PD JUL PY 1997 VL 57 IS 4 BP 431 EP 446 DI 10.1016/S0013-7944(97)00030-1 PG 16 WC Mechanics SC Mechanics GA XR608 UT WOS:A1997XR60800010 ER PT J AU GibsonWilde, DE Vincent, RA Souprayen, C Godin, S Hertzog, A Eckermann, SD AF GibsonWilde, DE Vincent, RA Souprayen, C Godin, S Hertzog, A Eckermann, SD TI Dual lidar observations of mesoscale fluctuations of ozone and horizontal winds SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID LOWER STRATOSPHERE; WAVES; TRANSPORT; LAMINAE; EASOE AB A case study is presented of 6.5 h of simultaneous colocated stratospheric Differential Absorption Lidar (DIAL) measurements of ozone concentration and Rayleigh-Mie Doppler (RD) lidar measurements of horizontal wind velocity from the Observatoire de Haute Provence (OHP), France (44 degrees N, 6 degrees E). The RD lidar observations reveal a distinct gravity wave motion at similar to 12-18 km, while the DIAL data show laminated ozone structures in the same height range. We combine these data to show that advection due to the gravity wave cannot produce the large ozone lamina at similar to 14 km. C1 CNRS,SERV AERON,F-75700 PARIS,FRANCE. COMPUTAT PHYS INC,FAIRFAX,VA 22031. USN,RES LAB,EO HULBURT CTR SPACE RES,WASHINGTON,DC 20375. RP GibsonWilde, DE (reprint author), UNIV ADELAIDE,DEPT PHYS & MATH PHYS,ADELAIDE,SA 5005,AUSTRALIA. RI Hertzog, Albert/A-2899-2012 NR 21 TC 13 Z9 14 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JUL 1 PY 1997 VL 24 IS 13 BP 1627 EP 1630 DI 10.1029/97GL01609 PG 4 WC Geosciences, Multidisciplinary SC Geology GA XJ380 UT WOS:A1997XJ38000021 ER PT J AU Liguori, F AF Liguori, F TI New approaches to weapon system testing or ''Back to the Future'' SO IEEE AEROSPACE AND ELECTRONIC SYSTEMS MAGAZINE LA English DT Article AB This paper proposes abandoning the use of multipurpose ATE for ''horizontal'' support of weapon systems in favor of returning to ''vertical'' support. An R&D effort is proposed to develop a software ''hot mock-up'' system for field testing weapon system assemblies. RP Liguori, F (reprint author), USN,AIR WARFARE DIV,DIV AIRCRAFT,SYST REQUIREMENTS BRANCH,CODE 4816,LAKEHURST,NJ 08733, USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0885-8985 J9 IEEE AERO EL SYS MAG JI IEEE Aerosp. Electron. Syst. Mag. PD JUL PY 1997 VL 12 IS 7 BP 31 EP 34 DI 10.1109/62.596654 PG 4 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA XH521 UT WOS:A1997XH52100009 ER PT J AU Rosenblum, L Durbin, J Doyle, R Tate, D King, R AF Rosenblum, L Durbin, J Doyle, R Tate, D King, R TI Situational awareness using the responsive workbench SO IEEE COMPUTER GRAPHICS AND APPLICATIONS LA English DT Editorial Material RP Rosenblum, L (reprint author), USN,RES LAB,ADV INFORMAT TECH BRANCH,CODE 5580,WASHINGTON,DC 20375, USA. NR 3 TC 4 Z9 4 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 SN 0272-1716 J9 IEEE COMPUT GRAPH JI IEEE Comput. Graph. Appl. PD JUL-AUG PY 1997 VL 17 IS 4 BP 12 EP 13 PG 2 WC Computer Science, Software Engineering SC Computer Science GA XG836 UT WOS:A1997XG83600005 ER PT J AU Wilson, OB Stewart, MS Wilson, JH Bourke, RH AF Wilson, OB Stewart, MS Wilson, JH Bourke, RH TI Noise source level density due to surf .1. Monterey Bay, CA SO IEEE JOURNAL OF OCEANIC ENGINEERING LA English DT Article DE shallow water; surf noise; underwater noise ID WIND-GENERATED NOISE; SHALLOW-WATER; AMBIENT NOISE; UNDERWATER SOUND; BREAKING WAVES; SEA-FLOOR AB Ambient noise measurements made in Monterey Bay, CA, in 1981 were reduced by estimations of wave-breaking noise and the residual noise was combined with modeled transmission loss (TL) to estimate the spectral source level of surf-generated noise, A Hamilton geoacoustic model of the coastal environment was derived and used in a finite-element parabolic equation propagation-loss model to obtain TL values, Estimates of both the continuous, or local, and discrete components of wave-breaking noise intensity were subtracted from the total measured noise held to determine the contribution due to surf only, Surf breaking on a uniform 12.5-km linear section of beach near Ft, Ord was found to be the dominant source of surf-generated noise. Estimated noise source level densities for heavy surf at Ft. Ord beach varied from 138 dB ref. 1 mu Pa . Hz(-1/2).m(-1) at 1 m from the source at 50 Hz to 107 dB at 1 kHz, with a slope of about -5 dB per octave, Although these results must be considered as preliminary, since they are based on a small number of measurements, they may be useful for prediction of ambient noise in other littoral regions. C1 USN,SEA SYST COMMAND,ARLINGTON,VA 22242. NEPTUNE SCI INC,SAN CLEMENTE,CA 92674. USN,POSTGRAD SCH,DEPT OCEANOG,MONTEREY,CA 93943. RP Wilson, OB (reprint author), USN,POSTGRAD SCH,DEPT PHYS,MONTEREY,CA 93943, USA. NR 40 TC 9 Z9 9 U1 1 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0364-9059 J9 IEEE J OCEANIC ENG JI IEEE J. Ocean. Eng. PD JUL PY 1997 VL 22 IS 3 BP 425 EP 433 DI 10.1109/48.611133 PG 9 WC Engineering, Civil; Engineering, Ocean; Engineering, Electrical & Electronic; Oceanography SC Engineering; Oceanography GA XN699 UT WOS:A1997XN69900003 ER PT J AU Fabre, JP Wilson, JH AF Fabre, JP Wilson, JH TI Noise source level density due to surf .2. Duck, NC SO IEEE JOURNAL OF OCEANIC ENGINEERING LA English DT Article ID SHALLOW-WATER; AMBIENT NOISE AB Ambient noise measurements collected off the coast of Duck, NC, were used in conjunction with modeled transmission loss (TL) and estimated ambient noise due to wave-breaking to generate estimates of spectral source level densities (per meter of surf zone) of surf-generated ambient noise, Estimates of both continuous (local) and discrete (distant) components of noise intensity due to breaking waves were subtracted from the total measured noise field in order to determine the contribution of the noise from the surf zone, Data for two days, representing high sea-state conditions, are presented, Estimated noise source level densities for heavy surf at Duck, NC, varied from 120 to 125 dB re 1 mu Pa/Hz(1/2)/m at 200 Hz to 90-100 dB re 1 mu Pa/Hz(1/2)/m at 900 Hz, with a slope of -5 dB per octave. Results compare well with previous surf noise studies conducted in Monterey Bay as reported in the companion paper by Wilson et al.. C1 NEPTUNE SCI INC,SAN DIEGO,CA 92123. USN,POSTGRAD SCH,DEPT OCEANOG,MONTEREY,CA 93943. RP Fabre, JP (reprint author), NEPTUNE SCI INC,SLIDELL,LA 70458, USA. NR 29 TC 4 Z9 4 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0364-9059 J9 IEEE J OCEANIC ENG JI IEEE J. Ocean. Eng. PD JUL PY 1997 VL 22 IS 3 BP 434 EP 444 DI 10.1109/48.611134 PG 11 WC Engineering, Civil; Engineering, Ocean; Engineering, Electrical & Electronic; Oceanography SC Engineering; Oceanography GA XN699 UT WOS:A1997XN69900004 ER PT J AU Apel, JR Badiey, M Chiu, CS Finette, S Headrick, R Kemp, J Lynch, JF Newhall, A Orr, MH Pasewark, BH Tielbuerger, D Turgut, A vonderHeydt, K Wolf, S AF Apel, JR Badiey, M Chiu, CS Finette, S Headrick, R Kemp, J Lynch, JF Newhall, A Orr, MH Pasewark, BH Tielbuerger, D Turgut, A vonderHeydt, K Wolf, S TI An overview of the 1995 SWARM shallow-water internal wave acoustic scattering experiment SO IEEE JOURNAL OF OCEANIC ENGINEERING LA English DT Article DE acoustic scattering; internal waves; shallow water ID LATE QUATERNARY SEDIMENTATION; JERSEY CONTINENTAL-SHELF; HORIZONTAL REFRACTION; GEORGES BANK; MODEL; SLOPE; SEA AB An overview is given of the July-August 1995 SWARM shallow-water internal wave acoustic scattering experiment. This experiment studied both acoustic propagation through and scattering by the linear and nonlinear internal waves found on the Mid-Atlantic Eight continental shelf, as well as the physical oceanography of the internal wavefield, In order that our goal of explaining the nature of the acoustic scattering should not be hindered by incomplete environmental knowledge, numerous instruments, both ship-deployed and moored, measured the acoustics, geophysics, and oceanography. In this paper, we show some of the results from the first year's analysis of the environmental and acoustic data, The environmental measurements, which are a key input to the analyses of the acoustic data, are given slightly more emphasis at this point in time, Some of the more interesting oceanographic, geophysical, and acoustical results we present here are: evidence for the dominance of the lee-wave mechanism for soliton production, evidence for the ''solibore internal tide,'' the ''dnoidal wave'' description of solitons, the inversion of chirp sonar data for bottom properties, propagation loss extraction from air-gun data, and the intensity and travel-time fluctuations seen in propagating acoustic normal modes. Directions for future research are outlined. C1 UNIV DELAWARE, GRAD COLL MARINE STUDIES, OCEAN ACOUST LAB, NEWARK, DE 19716 USA. USN, POSTGRAD SCH, MONTEREY, CA 93943 USA. USN, RES LAB, WASHINGTON, DC 20375 USA. WOODS HOLE OCEANOG INST, WOODS HOLE, MA 02543 USA. BUNDESWEHR WASSERSCHALL & GEOPHYS, FORSCH ANSTALT, D-24148 KIEL, GERMANY. RP GLOBAL OCEAN ASSOCIATES LAB, SILVER SPRING, MD 20908 USA. RI Badiey, Mohsen/H-3943-2012 NR 48 TC 172 Z9 191 U1 2 U2 9 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0364-9059 EI 1558-1691 J9 IEEE J OCEANIC ENG JI IEEE J. Ocean. Eng. PD JUL PY 1997 VL 22 IS 3 BP 465 EP 500 DI 10.1109/48.611138 PG 36 WC Engineering, Civil; Engineering, Ocean; Engineering, Electrical & Electronic; Oceanography SC Engineering; Oceanography GA XN699 UT WOS:A1997XN69900006 ER PT J AU Chiu, CS Miller, CW Lynch, JF AF Chiu, CS Miller, CW Lynch, JF TI Optimal modal beamforming of bandpass signals using an undersized sparse vertical hydrophone array: Theory and a shallow-water experiment SO IEEE JOURNAL OF OCEANIC ENGINEERING LA English DT Article DE acoustic filters; arrays; coupled-mode analysis; pulses; signal processing; tomography ID MESOSCALE; ACOUSTICS AB Conventional methods for modal beamforming of underwater acoustic signals using a vertical-line hydrophone array (VLA) can suffer significant degradation in resolution when the array is geometrically deficient, i.e., consists of sparsely spaced elements and spans the water column partially or is poorly navigated. Designed for estimating the coefficients of the normal modes, these conventional methods include the direct projection (DP) of the data on the calculated mode shapes and least-squares (LS) fitting of the mode sum to the data, The degradation, in the form of modal cross talk or sidelobes, Is a result of an undersampling in depth. This cross talk may be mitigated with the application of proper space-time filter constraints in the case of a pulse transmission. In this paper, a generalized least-squares (GLS) mode beamformer, capable of incorporating physical space-time constraints on the propagation of sound, is presented. The formulation is based on the well-known theorem of Gauss and Markov. Initialized by a model prediction of the basic arrival structure of the normal modes and incorporating, iteratively, refined estimates of the statistics of the modal fluctuations, this GLS technique strives to boost the resolution of a geometrically deficient VLA. The improvement is demonstrated using the VLA data collected during a shallow-water tomography experiment in the Barents Sea. The superiority of the GLS method over the conventional DP and LS methods is evident, providing a high-quality time series of modal arrivals as a function of geophysical time, which, in turn, reveals the dominant time scales of the oceanic processes associated with the Parents Sea Polar Front. C1 USN,POSTGRAD SCH,UNDERSEA WARFARE ACAD GRP,MONTEREY,CA 93943. WOODS HOLE OCEANOG INST,DEPT APPL OCEAN PHYS & ENGN,WOODS HOLE,MA 02543. RP Chiu, CS (reprint author), USN,POSTGRAD SCH,DEPT OCEANOG,MONTEREY,CA 93943, USA. NR 23 TC 7 Z9 7 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0364-9059 J9 IEEE J OCEANIC ENG JI IEEE J. Ocean. Eng. PD JUL PY 1997 VL 22 IS 3 BP 522 EP 533 DI 10.1109/48.611143 PG 12 WC Engineering, Civil; Engineering, Ocean; Engineering, Electrical & Electronic; Oceanography SC Engineering; Oceanography GA XN699 UT WOS:A1997XN69900008 ER PT J AU Gerlach, K Steiner, M Lin, FC AF Gerlach, K Steiner, M Lin, FC TI Detection of a spatially distributed target in white noise SO IEEE SIGNAL PROCESSING LETTERS LA English DT Article ID RADAR DETECTION AB A detector of a spatially distributed target in white Gaussian noise is developed, A reasonable distribution for the a priori target scatterer density is assumed, and a detector that incorporates this a priori knowledge is given. A simple detector form results, whose detection performance is robust over different scattering densities. RP Gerlach, K (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 7 TC 60 Z9 84 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1070-9908 J9 IEEE SIGNAL PROC LET JI IEEE Signal Process. Lett. PD JUL PY 1997 VL 4 IS 7 BP 198 EP 200 DI 10.1109/97.596885 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA XJ729 UT WOS:A1997XJ72900004 ER PT J AU Singh, RNP Bailey, WH AF Singh, RNP Bailey, WH TI Fuzzy logic applications to multisensor-multitarget correlation SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Article ID MEMBERSHIP FUNCTIONS; APPROXIMATE AB A consistent tactical picture requires data fusion technology to combine and propagate information received from diverse objects and usually vague situations. The information may be contained in two types of data; numerical data received from sensor measurements, and linguistic data obtained from human operators and domain experts. In real world situations, the numerical data may be noisy, inconsistent, and incomplete, and the linguistic information is imprecise and vague. To deal with these two types of data simultaneously, fuzzy sets and fuzzy logic provide a methodology to obtain an approximate but consistent tactical picture in a timely manner for very complex or ill-defined engineering problems. A functional paradigm for fuzzy data fusion is presented. It consists of four basic elements: 1) fuzzification of crisp elements, 2) fuzzy knowledge base derived from numerical input/output relations and humans, 3) fuzzy inference mechanism based on a class of fuzzy logic; 4) defuzzification of fuzzy outputs into crisp outputs for use by a plant. For real-time practical systems, the on-line determination of a fuzzy membership function from a given set of crisp inputs is vital. To this end, a methodology for estimating an optimal membership function from crisp input data has been implemented. This is based on the possibility/probability consistency principle as proposed by L. A. Zadeh. A relationship between the fuzzy membership function and the confidence level of statistical input data has been developed and it serves as a design parameter for fuzzification. This technique has been applied to a two-dimensional multisensor-multitarget tracking system. Fuzzy system performance evaluations have been presented. With simulated data in the laboratory environment, the simulation has been performed to evaluate the Mission Avionics Sensor Synergism (MASS) Systems. These results show better performance for the data correlation function using the fuzzy logic techniques. RP Singh, RNP (reprint author), NAVAL AIR WARFARE CTR,AIRCRAFT DIV,MAIL STOP 2,BLDG 2185,PATUXENT RIVER,MD 20670, USA. NR 23 TC 39 Z9 43 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9251 J9 IEEE T AERO ELEC SYS JI IEEE Trans. Aerosp. Electron. Syst. PD JUL PY 1997 VL 33 IS 3 BP 752 EP 769 DI 10.1109/7.599237 PG 18 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA XH348 UT WOS:A1997XH34800002 ER PT J AU Drumheller, DM Glasser, ML AF Drumheller, DM Glasser, ML TI Detection of chi-square fluctuating targets in arbitrary clutter SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Article ID WEIBULL AB In a recent paper, general expressions were derived for the density and cumulative probability functions of the amplitude of a linear matched-filter output given a nonfluctuating target in a clutter-limited environment. These expressions were based on the clutter amplitude density function. The results are extended to calculate the cumulative probability function of the output of a linear matched filter used to detect a chi-square fluctuating target in a clutter-limited environment. The resulting method is applied to a common radar clutter model, and experimental sonar data. C1 CLARKSON UNIV,DEPT PHYS,POTSDAM,NY 13699. RP Drumheller, DM (reprint author), USN,RES LAB,ACOUST DIV,CODE 7140,WASHINGTON,DC 20375, USA. NR 20 TC 6 Z9 7 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9251 J9 IEEE T AERO ELEC SYS JI IEEE Trans. Aerosp. Electron. Syst. PD JUL PY 1997 VL 33 IS 3 BP 784 EP 794 DI 10.1109/7.599243 PG 11 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA XH348 UT WOS:A1997XH34800004 ER PT J AU Trunk, GV Patel, DP AF Trunk, GV Patel, DP TI Optimal number of phased array faces and signal processors for horizon surveillance SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Letter AB The problem of the optimal number of phased array faces for performing 360 degrees horizon surveillance is considered. Assuming the detection performance is the same in all beam positions and the total number of T/R modules is constant, it is shown that the optimal number of array faces is three. This is true whether the arrays are operating simultaneously or sequentially. A parametric analysis is performed between the number of array faces operating simultaneously and the associated cost of simultaneous operation in terms of the size of the array. RP Trunk, GV (reprint author), USN,RES LAB,DIV RADAR,4555 OVERLOOK AVE SW,WASHINGTON,DC 20375, USA. NR 5 TC 5 Z9 5 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9251 J9 IEEE T AERO ELEC SYS JI IEEE Trans. Aerosp. Electron. Syst. PD JUL PY 1997 VL 33 IS 3 BP 1002 EP 1006 DI 10.1109/7.599324 PG 5 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA XH348 UT WOS:A1997XH34800025 ER PT J AU StGermain, KM Cavalieri, DJ AF StGermain, KM Cavalieri, DJ TI A microwave technique for mapping ice temperature in the arctic seasonal sea ice zone SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article; Proceedings Paper CT 1996 International Geoscience and Remote Sensing Symposium (IGARSS 96) - Remote Sensing for a Sustainable Future CY MAY 21-31, 1996 CL LINCOLN, NE SP IEEE, Geosci & Remote Sensing Soc, Univ Nebraska, Lincoln, NASA, NOAA, USN, Off Naval Res, US Natl Comm Union Radiosci Int, Canon Modern Methods Inc, Univ Nebraska Lincoln, Ctr Adv Land Management Informat Technol, Univ Nebraska Lincoln, Ctr Commun & Informat Sci, Univ Nebraska Lincoln, Ctr Electro Opt, Univ Nebraska Lincoln, Ctr Laser Anal Studies Trace Gas Dynam, Centurion Int Inc, Univ Nebraska Lincoln, Coll Engn & Technol, Univ Nebraska Lincoln, Dept Elect Engn, ERDAS Inc, Univ Nebraska Lincoln, High Plains Climate Ctr, Li Cor Inc, US Geol Survey EROS Data Ctr ID HIGH-RESOLUTION RADIOMETER; SURFACE-TEMPERATURE AB A technique for deriving ice temperature in the Arctic seasonal sea ice zone from passive microwave radiances has been developed, The algorithm operates on brightness temperatures derived from the Special Sensor Microwave/Imager (SSM/I) and uses ice concentration and type from a previously developed thin ice algorithm to estimate the surface emissivity. Comparisons of the microwave derived temperatures with estimates derived from infrared imagery of the Bering Strait yield a correlation coefficient of 0.93 and an RMS difference of 2.1 K when coastal and cloud contaminated pixels are removed, SSM/I temperatures were also compared with a time series of air temperature observations from Gambell on St, Lawrence Island and from Point Barrow, AK weather stations, These comparisons indicate that the relationship between the air temperature and the ice temperature depends on ice type. C1 NASA,GODDARD SPACE FLIGHT CTR,LAB HYDROSPHER PROC,GREENBELT,MD 20771. RP StGermain, KM (reprint author), USN,RES LAB,REMOTE SENSING DIV,CODE 7223,WASHINGTON,DC 20375, USA. NR 13 TC 1 Z9 1 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD JUL PY 1997 VL 35 IS 4 BP 946 EP 953 DI 10.1109/36.602536 PG 8 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA XL049 UT WOS:A1997XL04900016 ER PT J AU Ainsleigh, PL AF Ainsleigh, PL TI Observations on oblique projectors and pseudoinverses SO IEEE TRANSACTIONS ON SIGNAL PROCESSING LA English DT Article ID SIGNAL AB Oblique projectors (which were recently examined in this TRANSACTIONS by Behrens and Scharf) are related to earlier work on oblique pseudoinverses and constrained least-squares methods and are reconsidered from the standpoint of orthogonal basis vectors and QR factorizations. Construction algorithms are presented that are numerically more stable than the normal-equations constructions previously used. RP Ainsleigh, PL (reprint author), USN,CTR UNDERSEA WARFARE,NEWPORT,RI 02841, USA. NR 8 TC 9 Z9 9 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1053-587X J9 IEEE T SIGNAL PROCES JI IEEE Trans. Signal Process. PD JUL PY 1997 VL 45 IS 7 BP 1886 EP 1889 DI 10.1109/78.599966 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA XK373 UT WOS:A1997XK37300024 ER PT J AU Doolan, DL Hoffman, SL Southwood, S Wentworth, PA Sidney, J Chesnut, RW Keogh, E Appella, E Nutman, TB Lal, AA Gordon, DM Oloo, A Sette, A AF Doolan, DL Hoffman, SL Southwood, S Wentworth, PA Sidney, J Chesnut, RW Keogh, E Appella, E Nutman, TB Lal, AA Gordon, DM Oloo, A Sette, A TI Degenerate cytotoxic T cell epitopes from P-falciparum restricted by multiple HLA-A and HLA-B supertype alleles SO IMMUNITY LA English DT Article ID SPOROZOITE SURFACE PROTEIN-2; PLASMODIUM-FALCIPARUM; CIRCUMSPOROZOITE PROTEIN; GAMMA-INTERFERON; LYMPHOCYTES-T; INFECTED HEPATOCYTES; VACCINE DEVELOPMENT; PEPTIDE-BINDING; SEVERE MALARIA; RESPONSES AB We recently described human leukocyte antigen (HLA) A2, A3 and B7 supertypes, characterized by largely overlapping peptide-binding specificities and represented in a high percentage of different populations. Here, we identified 17 Plasmodium falciparum peptides capable of binding these supertypes and assessed antigenicity in both vaccinated and naturally exposed populations. Positive cytotoxic T lymphocyte recall and cytokine (interferon-gamma and tumor necrosis factor alpha) responses were detected for all peptides; all were recognized in the context of more than one HLA class I molecule; and at least 12 of the 17 were recognized in the context of all HLA alleles studied. These data validate the concept of HLA supertypes at the biological level, show that highly degenerate peptides are almost always recognized as epitopes, and demonstrate the feasibility of developing a universally effective vaccine by focusing on a limited number of peptide specificities. C1 CYTEL CORP,SAN DIEGO,CA 92121. NCI,NIH,BETHESDA,MD 20892. NIAID,PARASIT DIS LAB,NIH,BETHESDA,MD 20892. CTR DIS CONTROL & PREVENT,DIV PARASIT DIS,ATLANTA,GA 30333. WALTER REED ARMY MED CTR,WALTER REED ARMY INST RES,DEPT IMMUNOL,WASHINGTON,DC 20307. KENYA GOVT MED RES CTR,KISSIAN,KENYA. RP Doolan, DL (reprint author), USN,MED RES INST,MALARIA PROGRAM,BETHESDA,MD 20889, USA. RI Doolan, Denise/F-1969-2015 FU NIAID NIH HHS [N01-AI-45241] NR 59 TC 140 Z9 141 U1 1 U2 5 PU CELL PRESS PI CAMBRIDGE PA 1050 MASSACHUSETTES AVE, CIRCULATION DEPT, CAMBRIDGE, MA 02138 SN 1074-7613 J9 IMMUNITY JI Immunity PD JUL PY 1997 VL 7 IS 1 BP 97 EP 112 DI 10.1016/S1074-7613(00)80513-0 PG 16 WC Immunology SC Immunology GA XN693 UT WOS:A1997XN69300009 PM 9252123 ER PT J AU Hebbar, SK Platzer, MF Chang, WH AF Hebbar, SK Platzer, MF Chang, WH TI Control of high-incidence vortical flow on double-delta wings undergoing sideslip SO JOURNAL OF AIRCRAFT LA English DT Article; Proceedings Paper CT AIAA 34th Aerospace Sciences Meeting and Exhibit CY JAN 15-19, 1996 CL RENO, NV SP Amer Inst Aeronaut & Astronaut ID VORTEX FLOW; MODEL AB An experimental study of the vortical now over a baseline double-delta wing model and a diamond-fillet double-delta wing model, both with sharp leading edges, was conducted in a water tunnel using the dye-injection technique at a nominal now Reynolds number of 1.875 x 10(4). The diamond fillets at the strake/wing junction increased the wing area of the baseline model by 1%. The main focus of this study was to evaluate the effect of juncture fillets on the vortex core trajectory and the vortex burst location at high angles of attack with sideslip angle. Comparison of the test results between the baseline and the diamond-fillet models indicates a clear delay for the latter model in terms of both the vortex core trajectory, and the breakdown location at high angle of attack, with sideslip angles, The vortex breakdown data for the diamond-fillet model implies lift augmentation during sideslip motion, thus supporting the concept of how control using fillets, From the maneuvering viewpoint, the data suggest that the diamond-fillet model has a better operational envelope. RP Hebbar, SK (reprint author), USN,POSTGRAD SCH,DEPT AERONAUT & ASTRONAUT,MONTEREY,CA 93943, USA. NR 25 TC 5 Z9 5 U1 1 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD JUL-AUG PY 1997 VL 34 IS 4 BP 506 EP 513 DI 10.2514/2.2220 PG 8 WC Engineering, Aerospace SC Engineering GA XM726 UT WOS:A1997XM72600008 ER PT J AU Winton, MJ Russell, SD Gronsky, R AF Winton, MJ Russell, SD Gronsky, R TI Observation of competing etches in chemically etched porous silicon SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID PHOTOLUMINESCENCE; MECHANISM; WAFERS; SI AB Transmission electron microscopy and scanning electron microscopy offer evidence that the purely chemical HF:HNO3:H2O ''stain etch'' used to form light-emitting porous silicon is actually composed of competing etches. A localized etch forms the porous nanostructure by propagation of a discrete reaction interface into the silicon substrate, An amorphous surface layer (SiO2) that is a significant by-product of this etch has been observed and is believed to be a primary efficiency-limiting factor in attempts to fabricate chemically etched porous silicon devices, A destructive etch competes for ions in solution and removes both the porous silicon and the amorphous layers from the surface of the specimen when it becomes dominant, eventually quenching the luminescence properties. C1 USN,COMMAND CONTROL & OCEAN SURVEILLANCE CTR RES DEV,DEV TESTING & EVALUAT DIV,SAN DIEGO,CA 92152. UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. RP Winton, MJ (reprint author), UNIV CALIF BERKELEY,DEPT MAT SCI & MINERAL ENGN,BERKELEY,CA 94720, USA. NR 15 TC 11 Z9 11 U1 0 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUL 1 PY 1997 VL 82 IS 1 BP 436 EP 441 DI 10.1063/1.365833 PG 6 WC Physics, Applied SC Physics GA XG880 UT WOS:A1997XG88000063 ER PT J AU Oxford, GE Quintero, G Stuller, CB Gher, ME AF Oxford, GE Quintero, G Stuller, CB Gher, ME TI Treatment of 3rd molar-induced periodontal defects with guided tissue regeneration SO JOURNAL OF CLINICAL PERIODONTOLOGY LA English DT Article DE 3rd molars; guided tissue regeneration; probing attachment levels ID ATTACHMENT FORMATION; ENDOTOXINS; LIGAMENT; SURGERY; REMOVAL; GROWTH AB Recent reports provide evidence of increased attachment levels when using guided tissue regeneration (GTR) techniques for the treatment of periodontal defects. Periodontal defects frequently occur at the distal aspect of mandibular 2nd molars which are next to mesioangular impacted 3rd molars that have oral communication. The purpose of this study was to determine whether the use of GTR can enhance probing attachment levels (PALs) following extraction of mesioangular impacted third molars. 12 patients with bilateral soft tissue impacted mandibular 3rd molars entered this split mouth study. After extractions, the previously exposed distal root surface of the 2nd molars were debrided. The defects on the randomly selected experimental sites were covered with expanded polytetraflouro-ethylene (e-PTFE) membrane and the tissue was replaced to cover the membrane. Membranes were removed after 6 weeks. Control sites were treated identically except no membrane was placed. GI, P1I, PD, PAL and BOP records were obtained at 0, 3 and 6 months. The use of barrier material did not provide statistically-significant differences in PAL when comparing experimental versus control sites. Nevertheless, PAL gain was consistently greater at 3 and 6 months when GTR techniques were used in sites with deep impactions. C1 PRIVATE PRACTICE LTD PERIODONT,ATLANTA,GA. USN ACAD,BRANCH DENT CLIN,DEPT ORAL SURG,ANNAPOLIS,MD 21402. PRIVATE PRACTICE LTD PERIODONT,CARLSBAD,CA. RP Oxford, GE (reprint author), UNIV FLORIDA,COLL MED,DEPT ORAL BIOL,JHMHSC BOX 100424,GAINESVILLE,FL 32610, USA. NR 28 TC 23 Z9 23 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0303-6979 J9 J CLIN PERIODONTOL JI J. Clin. Periodontol. PD JUL PY 1997 VL 24 IS 7 BP 464 EP 469 DI 10.1111/j.1600-051X.1997.tb00213.x PG 6 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA XG874 UT WOS:A1997XG87400003 PM 9226386 ER PT J AU Anderson, HH Rapley, JW Williams, DR AF Anderson, HH Rapley, JW Williams, DR TI Gingival overgrowth with valproic acid: A case report SO JOURNAL OF DENTISTRY FOR CHILDREN LA English DT Article ID SODIUM VALPROATE; PHENYTOIN; HYPERPLASIA; CYCLOSPORIN; FIBROBLASTS; HEALTH C1 USN,DENT CTR,JACKSONVILLE,FL. RP Anderson, HH (reprint author), UNIV MISSOURI,SCH DENT,DEPT GRAD PERIODONT,650 E 25TH ST,KANSAS CITY,MO 64108, USA. NR 20 TC 11 Z9 13 U1 0 U2 0 PU AMER SOC DENTISTRY CHILD PI CHICAGO PA JOHN HANCOCK CENTER, 875 N MICHIGAN AVE, STE 4040, CHICAGO, IL 60611-1901 SN 0022-0353 J9 J DENT CHILD JI J. Dent. Child. PD JUL-AUG PY 1997 VL 64 IS 4 BP 294 EP & PG 5 WC Dentistry, Oral Surgery & Medicine; Pediatrics SC Dentistry, Oral Surgery & Medicine; Pediatrics GA YA953 UT WOS:A1997YA95300015 PM 9328685 ER PT J AU Sarpkaya, T AF Sarpkaya, T TI Dynamics of a hydroelastic cylinder with very low mass and damping - Discussion SO JOURNAL OF FLUIDS AND STRUCTURES LA English DT Editorial Material RP Sarpkaya, T (reprint author), USN,POSTGRAD SCH,700 DYER RD,RM 339,MONTEREY,CA 93943, USA. NR 10 TC 1 Z9 1 U1 2 U2 6 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0889-9746 J9 J FLUID STRUCT JI J. Fluids Struct. PD JUL PY 1997 VL 11 IS 5 BP 549 EP 551 DI 10.1006/jfls.1997.0090 PG 3 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA XX203 UT WOS:A1997XX20300007 ER PT J AU Carpenter, DL Sonwalkar, VS Helliwell, RA Walt, M Inan, US Ikeda, M Caudle, DL AF Carpenter, DL Sonwalkar, VS Helliwell, RA Walt, M Inan, US Ikeda, M Caudle, DL TI Probing properties of the magnetospheric hot plasma distribution by whistler mode wave injection at multiple frequencies: Evidence of spatial as well as temporal wave growth SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID VLF; TRANSMITTER; EXCITATION; SIGNALS AB This is the second of two papers on the use of whistler mode wave injection to investigate properties of the magnetospheric hot plasma. Paper 1, [Sonwalkar et al., this issue] emphasized the use of signals at a single frequency to identify longitudinal structures ranging from 100 to 25,000 km in extent in similar to 1-10 keV electrons drifting azimuthally through whistler ducts. This short paper discusses and illustrates the use of wave injection at multiple discrete frequencies to study temporal changes in magnetospheric hot electrons with parallel (gyroresonant) velocities in various nonoverlapping ranges. As in paper 1, the data studied were acquired during a special 9-hour period of 1.9 - 2.9 kHz VLF transmissions from Siple Station, Antarctica, to Lake Mistissini, Canada, on January 23-24, 1988. The amplitudes of the leading edges of constant frequency pulses at 1900, 2150, and 2400 Hz were found to vary independently with time. This is interpreted as evidence of a spatial amplification process that accompanied the well known and more readily identifiable phenomena of exponential temporal growth to a saturation level. Evidence of wave-hot plasma interactions showed a dependence on df/dt of the input signal frequency versus time format; in general, the slow frequency ramps showed the highest amplitudes and the fast ramps and parabolas the lowest, in agreement with past work. C1 USN,POSTGRAD SCH,MONTEREY,CA 93943. MUSASHI UNIV,TOKYO 106,JAPAN. UNIV ALASKA,INST NO ENGN,FAIRBANKS,AK 99775. RP Carpenter, DL (reprint author), STANFORD UNIV,STAR LAB,STANFORD,CA 94305, USA. NR 11 TC 6 Z9 6 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD JUL 1 PY 1997 VL 102 IS A7 BP 14355 EP 14362 DI 10.1029/96JA03046 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XJ204 UT WOS:A1997XJ20400030 ER PT J AU Sonwalkar, VS Carpenter, DL Helliwell, RA Walt, M Inan, US Caudle, DL Ikeda, M AF Sonwalkar, VS Carpenter, DL Helliwell, RA Walt, M Inan, US Caudle, DL Ikeda, M TI Properties of the magnetospheric hot plasma distribution deduced from whistler mode wave injection at 2400 Hz: Ground-based detection of azimuthal structure in magnetospheric hot plasmas SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID SIPLE VLF TRANSMITTER; FINE-STRUCTURE; SIGNALS; ANTARCTICA; EXCITATION; GENERATION; FREQUENCY; THRESHOLD; SIDEBANDS; STATION AB Siple station VLF wave injection experiments aimed at finding the properties of the magnetospheric hot plasma were conducted for a 9-hour period between 1705 and 0210 UT on January 23-24, 1988. A special frequency versus time format, lasting 1 min and transmitted every 5 min, consisted of a sequence of pulses, frequency ramps, and parabolas, all in a 1-kHz range centered on 2400 Hx. The transmitted signals, after propagating along a geomagnetic field-aligned duct, were recorded at Lake Mistissini, Canada. At various times during the 9-hour interval the Siple signals showed features characteristic of wave-particle interactions, including wave growth, sidebands, and triggered emissions. Our observations, primarily at 2400 Hz, show that (1) there were no correlations between the initial levels, the growth rates, and the saturation levels of constant-frequency pulses; (2) in general, the values of growth rate and saturation level of two pulses injected within 30 s were nearly the same; (3) the initial level, growth rate, and saturation level showed temporal variations over 5-15 min and 1-2 hour timescales; (4) the leading edges of constant-frequency signals underwent spatial amplification; and (5) under conditions of saturation the received signal bandwidth (similar to 20 Hz) remained constant over a 1-hour period, although the saturation level and growth rate varied during the same period. On the assumption that gyroresonant interactions were responsible for the observed wave growth and saturation, the timescales over which those phenomena varied provide constraints on the possible energetic electron population within the duct. In the reference frame of the duct (L similar to 5.1, N-e similar to 280 cm(-3)) the particle fluxes showed no variation over a 30-s timescale but varied over 5-15 min and 1-2 hour timescales. The 5-15 min timescale variations indicate longitudinal structures ranging from similar to 0.20 or similar to 100 km (in the equatorial plane) for electrons with energy E = 0.6 keV and pitch angle alpha = 40 degrees, to similar to 5 degrees or similar to 2800 km for electrons with energy E = 11 keV and pitch angle alpha = 80 degrees. The hour-long time variations indicate longitudinal structures ranging from similar to 2 degrees or similar to 1100 km (in the equatorial plane) for electrons with energy E = 0.6 keV and pitch angle alpha = 40 degrees, to similar to 45 degrees or similar to 25,000 km for electrons with energy E = 11 keV and pitch angle alpha = 80 degrees. We conclude that ground-based active and passive wave experiments have substantial potential for investigating properties of the hot plasma of the magnetosphere. C1 STANFORD UNIV,STAR LAB,STANFORD,CA 94305. USN,POSTGRAD SCH,MONTEREY,CA 93943. MUSASHI UNIV,TOKYO 106,JAPAN. RP Sonwalkar, VS (reprint author), UNIV ALASKA,INST NO ENGN,FAIRBANKS,AK 99775, USA. NR 38 TC 11 Z9 11 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD JUL 1 PY 1997 VL 102 IS A7 BP 14363 EP 14380 DI 10.1029/96JA03047 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XJ204 UT WOS:A1997XJ20400031 ER PT J AU Strickland, DJ Majeed, T Evans, JS Meier, RR Picone, JM AF Strickland, DJ Majeed, T Evans, JS Meier, RR Picone, JM TI Analytical representation of g factors for rapid, accurate calculation of excitation rates in the dayside thermosphere SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ELECTRON-IMPACT EXCITATION; EXTREME ULTRAVIOLET EMISSION; SOLAR EUV FLUX; CROSS-SECTIONS; ATOMIC OXYGEN; PHOTOELECTRON FLUX; MEDIUM-RESOLUTION; UPPER-ATMOSPHERE; TRANSPORT; MODEL AB An algorithm has been developed that rapidly and accurately calculates altitude profiles of volume excitation rates for many species of aeronomic interest. These rates may be specified as functions of solar activity (specific to the Hinteregger et al. [1981] model in this phase of the work) and solar zenith angle (SZA). The algorithm relies on an analytical expression for the g factor as a function of total vertical column density. The g factor for a given state and excitation process can be defined as the direct volume excitation rate for this process divided by the density of the species involved in the direct excitation. Modeling results from this work show that g, when expressed as a function of total vertical column density, is independent of model atmosphere within a small error illustrated in the text. The dependence within g then reduces to solar activity (characterized by F-10.7) and SZA. Extensive photoelectron transport calculations have been performed that provide numerical g factors for 22 excitation processes, 3 F-10.7 values (75, 150, and 250), and 8 solar zenith angles (0 degrees, 45 degrees, 60 degrees, 70 degrees, 80 degrees, 85 degrees, 87 degrees, and 90 degrees). The results have been fitted with a 10 coefficient analytical expression comprised of a function based on an analytical solution to a simplified photoelectron transport equation and two Gaussian functions needed for structure because of soft X ray energy deposition. The resulting coefficients are used to calculate g factors for user-specified pairs of F-10.7 and SZA by two-dimensional interpolation. By inputting a model atmosphere the corresponding volume excitation rates may also be specified. For photoionization excitation the analytic expression for the g factor is much simpler. Results presented herein include comparisons between numerical g factors and their fits, along with examples of both g factors and corresponding volume excitation rates for the purpose of showing the effects of changing solar activity and SZA. Tables are included that identify excitation processes, identify additional processes that must be considered to derive emission rates, and provide cross-section information for the electron impact processes addressed in this work. C1 USN,RES LAB,EO HULBURT CTR SPACE RES,WASHINGTON,DC 20375. RP Strickland, DJ (reprint author), COMPUTAT PHYS INC,2750 PROSPER AVE,SUITE 600,FAIRFAX,VA 22031, USA. RI Meier, Robert/G-4749-2014 OI Meier, Robert/0000-0001-8497-7115 NR 41 TC 10 Z9 10 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD JUL 1 PY 1997 VL 102 IS A7 BP 14485 EP 14498 DI 10.1029/97JA00943 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XJ204 UT WOS:A1997XJ20400041 ER PT J AU Chen, J Cargill, PJ Palmadesso, PJ AF Chen, J Cargill, PJ Palmadesso, PJ TI Predicting solar wind structures and their geoeffectiveness SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID INTERPLANETARY MAGNETIC CLOUDS; RECURRENT GEOMAGNETIC DISTURBANCES; CORONAL HOLES; 1 AU; STORMS; MAGNETOSPHERE; FILAMENTS; PASSAGE; FIELDS; DST AB This paper describes a feature-based pattern-recognition technique that utilizes real-time solar wind measurements to identify and predict the occurrence of solar wind structures that can cause geomagnetic storms. The technique is based on the knowledge that storms are caused by solar wind events with certain identifiable features, the two most important ones being (1) extended periods and (2) large amplitudes of southward interplanetary magnetic field (B-z < 0). Using the measured solar wind properties available at the current time t the profiles of the north-south magnetic field component, B-z((t) over cap), and the east-west component, B-y((t) over cap), are estimated for the solar wind that has yet to arrive, where (t) over cap is the future time. On the basis of the estimated B-z and B-y profiles the occurrence, onset time, duration, and severity of impending storms are predicted. It is shown that the occurrence and durations of large storms exceeding a predetermined threshold can be predicted accurately. Successful predictions can be made after examining the initial similar to 20% of a geoeffective (i.e., storm-causing) structure. For long-duration southward B, events such as magnetic clouds the advance prediction time can be from several hours to in excess of 10 hours. The technique is tested using 5 months of historical solar wind data. We develop a procedure to extend the capability of the technique by incorporating additional features. Reduction of potential ''false alarms'' and ''misses'' resulting from such extensions is discussed. RP Chen, J (reprint author), USN,RES LAB,DIV PLASMA PHYS,CODE 6790,4555 OVERLOOK AVE,SW,WASHINGTON,DC 20375, USA. NR 42 TC 23 Z9 23 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD JUL 1 PY 1997 VL 102 IS A7 BP 14701 EP 14720 DI 10.1029/97JA00936 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XJ204 UT WOS:A1997XJ20400057 ER PT J AU Sofair, I AF Sofair, I TI Improved method for calculating exact geodetic latitude and altitude SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article RP Sofair, I (reprint author), USN,CTR SURFACE WARFARE,STRATEG SYST DEPT,DAHLGREN,VA 22448, USA. NR 8 TC 7 Z9 7 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD JUL-AUG PY 1997 VL 20 IS 4 BP 824 EP 826 DI 10.2514/2.4119 PG 3 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA XJ436 UT WOS:A1997XJ43600028 ER PT J AU Cahill, AM AF Cahill, AM TI Empowerment - Answering the white phone first SO JOURNAL OF NURSING ADMINISTRATION LA English DT Editorial Material RP Cahill, AM (reprint author), USN,NURSE CORPS,WASHINGTON,DC 20350, USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT-RAVEN PUBL PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 SN 0002-0443 J9 J NURS ADMIN JI J. Nurs. Adm. PD JUL-AUG PY 1997 VL 27 IS 7-8 BP 5 EP 6 DI 10.1097/00005110-199707000-00002 PG 2 WC Nursing SC Nursing GA XQ966 UT WOS:A1997XQ96600001 PM 9267381 ER PT J AU Jorgensen, MG AF Jorgensen, MG TI Prevalence of amlodipine-related gingival hyperplasia SO JOURNAL OF PERIODONTOLOGY LA English DT Article DE gingival hyperplasia, etiology; amlodipine, adverse effects ID NIFEDIPINE; OVERGROWTH; SEQUESTRATION; HYPERTENSION; SEVERITY; PLAQUE AB CALCIUM CHANNEL BLOCKERS ARE KNOWN to contribute to gingival hyperplasia. The vast majority of reports discuss patients taking the drug nifedipine, During the past few years a newer calcium channel blocker, amlodipine, has been used with increasing frequency. To date, six cases have been published indicating that amlodipine may also promote gingival hyperplasia; however no data have been reported regarding the prevalence of this phenomenon. The purpose of this study was to examine a large group of patients taking amlodipine and determine the prevalence of gingival hyperplasia. One hundred fifty dentate patients who had been taking amlodipine, 5 mg per day for at least 6 months, volunteered to undergo a screening examination fur gingival hyperplasia, Mild hyperplasia (<1/3 clinical crown) was found in five patients-a prevalence of 3.3%. This is significantly less (P < .001) than rates reported for patients taking nifedipine, and not significantly different from rates previously reported in control groups of cardiac patients not taking calcium channel blockers. The results from this group of patients indicated that amlodipine, 5 mg per day, did not induce gingival hyperplasia. C1 USN,MED CTR,DEPT DENT,SAN DIEGO,CA 92152. RP Jorgensen, MG (reprint author), USN,MED CTR,DEPT CLIN INVEST,34800 BOB WILSON DR,SAN DIEGO,CA 92134, USA. NR 30 TC 33 Z9 37 U1 2 U2 5 PU AMER ACAD PERIODONTOLOGY PI CHICAGO PA 737 NORTH MICHIGAN AVENUE, SUITE 800, CHICAGO, IL 60611-2690 SN 0022-3492 J9 J PERIODONTOL JI J. Periodont. PD JUL PY 1997 VL 68 IS 7 BP 676 EP 678 PG 3 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA XM934 UT WOS:A1997XM93400009 PM 9249639 ER PT J AU Scott, TA Towle, HJ Assad, DA Nicoll, BK AF Scott, TA Towle, HJ Assad, DA Nicoll, BK TI Comparison of bioabsorbable laminar bone membrane and non-resorbable ePTFE membrane in mandibular furcations SO JOURNAL OF PERIODONTOLOGY LA English DT Article DE furcation, therapy; guided tissue regeneration; membranes, artificial; membranes, barrier; polytetrafluoroethylene, therapeutic use; grafts, bone; bone, demineralized ID GUIDED TISSUE REGENERATION; FREEZE-DRIED BONE; HISTOLOGIC EVALUATION; PERIODONTAL TISSUES; DEFECTS; ALLOGRAFT; INVASIONS; REENTRY; BARRIER; THERAPY AB THE PURPOSE OF THIS STUDY was to compare clinical parameter changes and osseous regeneration in 12 pairs of comparable Class II mandibular molar furcation invasion defects using either a bioabsorbable demineralized laminar bone allograft membrane or a non-resorbable expanded polytetrafluoroethylene (ePTFE) membrane as a barrier in guided tissue regeneration. Measurements with calibrated periodontal probes were made to determine soft tissue recession, probing depth, and attachment levels. Defects within each pair were randomly selected for treatment with either bioabsorbable demineralized bone allograft membrane or ePTFE membrane. All defects were concurrently grafted with particulate demineralized freeze-dried bone allograft (DFDBA). Additional measurements were made at surgery to determine crestal resorption and the vertical and horizontal dimensions of the osseous defects. The temporal course and extent of membrane exposures were also recorded. The non-resorbable membrane was retrieved 6 weeks following placement. Six months following initial surgical treatment, each site was surgically re-entered and all soft and hard tissue measurements repeated. Descriptive statistical analysis revealed that both treatments resulted in significant within-group mean vertical and horizontal osseous fill, but no statistical difference emerged between the groups. As based on this pilot study, laminar bone membrane may be as effective as ePTFE when used in conjunction with DFDBA for treatment of Class II mandibular molar furcation bone defects. This pilot study of low power suggests that these two materials may be equivalent when used in conjunction with DFDBA. Further studies of much higher power and of the laminar bone alone as compared to positive and negative controls are required. Laminar bone does not require a secondary surgical procedure for removal and may undergo less frequent instances and degrees of exposure during healing. C1 USN,DENT RES INST,BETHESDA,MD 20084. WL GORE & ASSOC INC,GORE TEX,FLAGSTAFF,AZ. RP Scott, TA (reprint author), USN,SCH DENT,NATL NAVAL DENT CTR,DEPT PERIODONT,8901 WISCONSIN AVE,BETHESDA,MD 20889, USA. NR 24 TC 18 Z9 18 U1 0 U2 1 PU AMER ACAD PERIODONTOLOGY PI CHICAGO PA 737 NORTH MICHIGAN AVENUE, SUITE 800, CHICAGO, IL 60611-2690 SN 0022-3492 J9 J PERIODONTOL JI J. Periodont. PD JUL PY 1997 VL 68 IS 7 BP 679 EP 686 PG 8 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA XM934 UT WOS:A1997XM93400010 PM 9249640 ER PT J AU Bao, XL Uberall, H Niemiec, J Decultot, D Lecroq, F Maze, G Ripoche, J AF Bao, XL Uberall, H Niemiec, J Decultot, D Lecroq, F Maze, G Ripoche, J TI The resonances of finite-length elastic cylinders and elastic spheroids excited by sound scattering SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID ACOUSTIC SCATTERING; ASPECT RATIOS; OBJECTS; MATRIX AB The predictions of resonance frequencies for elongated elastic cylinders and spheroids, based on various methods of approach, were discussed in a number of papers in recent years. In the present study, the regions of applicability of the phase matching method for surface waves and of the longitudinal bar wave approximation are examined by comparing the predicted results with the results of T-matrix calculations or with the results of scattering experiments. (C) 1997 Acoustical Society of America. C1 UNIV HAVRE,ACOUST ULTRASONORE & ELECT LAB,CNRS,URA 1373,F-76610 LE HAVRE,FRANCE. CATHOLIC UNIV AMER,DEPT PHYS,WASHINGTON,DC 20064. NSWC,CARDEROCK DIV,CARDEROCK,MD 20817. NR 13 TC 4 Z9 4 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JUL PY 1997 VL 102 IS 1 BP 49 EP 54 DI 10.1121/1.419723 PG 6 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA XL752 UT WOS:A1997XL75200003 ER PT J AU Kulkarni, RS Siegmann, WL Collins, MD AF Kulkarni, RS Siegmann, WL Collins, MD TI Nonlinear wide-angle paraxial acoustic propagation in shallow-water channels SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID CONSERVING PARABOLIC EQUATION; TIME-DOMAIN SOLUTION; UNDERWATER ACOUSTICS; ELASTIC MEDIA; OCEAN; DENSITY AB A time-domain model that describes wide-angle paraxial propagation of acoustic pulses in shallow water is developed. This model incorporates weak nonlinear effects and depth variability in both ambient density and sound speed. Derivations of paraxial approximations are based on an iterative approach, in which the wide-angle approximation is obtained by using a narrow-angle equation to approximate the second range derivative in the two-way equation. Scaling arguments are used to obtain a more tractable simplification of the equation. The wide-angle equation is solved numerically by splitting into components representing distinct physical processes and using a modified version of the time-domain parabolic equation (TDPE) code [M. D. Collins, J. Acoust. Soc. Am. 84, 2114-2125 (1988)]. A high-order upwind flux-correction method is modified to handle the nonlinear component. Numerical results are presented for adiabatic propagation in a shallow, isospeed channel. It is demonstrated that nonlinear effects are significant, even at small ranges, if the peak source pressure is high enough. Both nonlinear and wide-angle effects are illustrated, and their differences are discussed. (C) 1997 Acoustical Society of America. C1 USN,RES LAB,WASHINGTON,DC 20375. RP Kulkarni, RS (reprint author), RENSSELAER POLYTECH INST,TROY,NY 12180, USA. NR 36 TC 3 Z9 3 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JUL PY 1997 VL 102 IS 1 BP 224 EP 232 DI 10.1121/1.419815 PG 9 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA XL752 UT WOS:A1997XL75200025 ER PT J AU Abawi, AT Kuperman, WA Collins, MD AF Abawi, AT Kuperman, WA Collins, MD TI The coupled mode parabolic equation SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID HEARD ISLAND; ACOUSTIC PROPAGATION; SOUND-PROPAGATION; PENETRABLE BOTTOM; OCEAN ACOUSTICS; RANGE; DEPTH; WAVEGUIDE; BERMUDA; FIELDS AB The coupled mode parabolic equation (PE) is a generalization of the adiabatic mode RE that includes mode coupling terms. It is practical to apply this approach to large-scale problems involving coupling of energy between both modes and azimuths. The solution is expressed in terms of the normal modes and mode coefficients, which satisfy coupled horizontal wave equations. The coupled mode PE may be solved efficiently with the splitting method. The first step is equivalent to solving the adiabatic mode PE over one range step. The second step involves the integration of the coupling term. The coupling mode PE solution conserves energy, which is an important aspect of a range-dependent propagation model. The derivation of the coupled mode PE, which involves completing the square of an operator, is related to the derivation of an adiabatic mode PE that accounts for ambient flow. Examples are presented to illustrate the accuracy of the coupled mode PE. (C) 1997 Acoustical Society of America. C1 UNIV CALIF SAN DIEGO,SCRIPPS INST OCEANOG,LA JOLLA,CA 92093. USN,RES LAB,WASHINGTON,DC 20375. NR 40 TC 31 Z9 36 U1 2 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JUL PY 1997 VL 102 IS 1 BP 233 EP 238 DI 10.1121/1.419819 PG 6 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA XL752 UT WOS:A1997XL75200026 ER PT J AU Butler, SC Butler, JL Butler, AL Cavanagh, GH AF Butler, SC Butler, JL Butler, AL Cavanagh, GH TI A low-frequency directional flextensional transducer and line array SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB A unique low-frequency (900 Hz) class IV flextensional transducer that produces an enhanced far-field pressure on one side and canceled far-field pressure on the other side has been developed. The transducer radiating surface consists of a thick-walled elliptical aluminum shell and a U.S. Navy type III piezoelectric stack along its major axis with two active sections and one inactive section. The directionality is achieved by simultaneously exciting the shell into an omnidirectional and dipole operation by driving stack into both extensional and bending modes. Both measurements and modeling on this device show a front to back pressure ratio of more than 30 dB, producing cardioid-type radiation patterns over an octave band. for a single transducer element. The transducers measured mechanical Q is 8, coupling coefficient is 0.25, and electroacoustic efficiency is 80% and produced a source level of 215 dB re: 1 mu Pa at 1 m when driven at a field limit of 394 kV/m (10 kV/in.) at resonance. The uniqueness of this transducer is its directional beam patterns (directivity index=3.4 dB) and high acoustic output power from a small (less than a third of a wavelength) single element. Six of these transducers were placed in a closely packed line array two-wavelengths long, The array successfully produced narrow directional sound beams (directivity index=8.7 dB) with a front to back ratio greater than 30 dB and a source level of 225 dB re: 1 mu Pa at 1 m. (C) 1997 Acoustical Society of America. C1 IMAGE ACOUST INC,COHASSET,MA 02025. MASSA PROD CORP,HINGHAM,MA 02043. RP Butler, SC (reprint author), USN,UNDERSEA WARFARE CTR,NEWPORT,RI 02841, USA. NR 7 TC 16 Z9 16 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JUL PY 1997 VL 102 IS 1 BP 308 EP 314 DI 10.1121/1.419609 PG 7 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA XL752 UT WOS:A1997XL75200034 ER PT J AU Photiadis, DM AF Photiadis, DM TI Acoustics of a fluid-loaded plate with attached oscillators .1. Feynman rules SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB The ''fuzzy structure'' paradigm developed by Soize and others provides a framework within which the acoustic properties of systems with complex internal structure can be explored. In this two part paper, the acoustic properties of one of the simplest such systems, a fluid-loaded plate with attached internal oscillators, are explored. In Part I, the theoretical tools needed in this investigation, the representation of the Neumann series in terms of Feynman diagrams, is presented. In most ways, the formal aspects of this development are identical to similar results from other disciplines, but the presence of damping in the system, either internal or due to radiation into the fluid, requires one to make some modifications to existing theories. The rules for evaluating averaged quantities such as G...GG*...G* involving higher-order products of the Green's function are given. These quantities are necessary to determine a number of relevant properties of the system including the scattering cross section and the size of typical fluctuations. The Feynman rules, detailed mathematical expressions which enable averaged quantities to be evaluated for particular systems, are explicitly given for the case in which the internals are simple oscillators distributed uniformly and independently in both space and frequency. In Part II of this paper, the theoretical approach will be applied to predict a number of acoustic properties of the system. RP Photiadis, DM (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 14 TC 4 Z9 4 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JUL PY 1997 VL 102 IS 1 BP 348 EP 357 DI 10.1121/1.419758 PG 10 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA XL752 UT WOS:A1997XL75200039 ER PT J AU Lowrey, AH Famini, GR Wilson, LY AF Lowrey, AH Famini, GR Wilson, LY TI Using theoretical descriptors in quantitative structure-property relationships: Gas phase acidity of some hydrocarbons and nitrohydrocarbons SO JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 2 LA English DT Article ID AFFINITIES AB Calculation of the gas phase acidity of some hydrocarbons and nitrohydrocarbons is studied using direct (quantum mechanical) methods as well as a model equation, derived with the aid of correlation analysis, relating empirical values to computational molecular parameters, Agreement between directly calculated and empirical values is improved by correlation equations, The correlation analysis model is statistically significant and physically reasonable; gas phase acidity increases with acidity modelling parameters and decreases with basicity modelling parameters. C1 LA SIERRA UNIV,DEPT CHEM,RIVERSIDE,CA 92515. US ARMY EDGEWOOD RES,CTR DEV & ENGN,ABERDEEN PROVING GROUND,MD 21010. USN,RES LAB,LAB STRUCT & MATTER,WASHINGTON,DC 20375. NR 24 TC 9 Z9 9 U1 0 U2 1 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON ROAD, CAMBRIDGE, CAMBS, ENGLAND CB4 4WF SN 0300-9580 J9 J CHEM SOC PERK T 2 JI J. Chem. Soc.-Perkin Trans. 2 PD JUL PY 1997 IS 7 BP 1381 EP 1388 DI 10.1039/a607448k PG 8 WC Chemistry, Organic; Chemistry, Physical SC Chemistry GA XL563 UT WOS:A1997XL56300023 ER PT J AU Ko, YD Kim, YD Cooper, SL Klein, MV Park, JH Jonker, BT AF Ko, YD Kim, YD Cooper, SL Klein, MV Park, JH Jonker, BT TI Spectroscopic ellipsometric observation of charge transfer transitions in Zn1-xCoxSe films SO JOURNAL OF THE KOREAN PHYSICAL SOCIETY LA English DT Article; Proceedings Paper CT International Conference on Advanced Materials and Devices 96 CY JUN 11-13, 1996 CL KANGWAN DO, SOUTH KOREA ID SPECTRA AB We report the observation by spectroscopic ellipsometry of a charge-transfer-type p-to-d transition in Zn1-xCoxSe films grown on GaAs substrates with 0 less than or equal to x < 0.1. For x > 0.04 samples, we observed an absorption feature near 4.3 eV within the E-0 + Delta(0) - E-1 band gap region. This new structure appears to have the characteristics of a charge-transfer-type p-to-d transition. A many body approach was used to interpret this feature as a local charge-transfer transition. Another observation, the decrease of the interference pattern above 2.2 eV, was explained as a nonlocal charge-transfer transition. A calculation using a multilayer model (air/Zn1-xCoxSe/GaAs) showed the same behavior as that of the measured spectrum. C1 KYUNG HEE UNIV,RES INST BASIC SCI,SEOUL 130701,SOUTH KOREA. UNIV ILLINOIS,DEPT PHYS,URBANA,IL 61801. UNIV ILLINOIS,MAT RES LAB,URBANA,IL 61801. AT&T BELL LABS,MURRAY HILL,NJ 07974. USN,RES LAB,WASHINGTON,DC 20375. RP Ko, YD (reprint author), KYUNG HEE UNIV,DEPT PHYS,SEOUL 130701,SOUTH KOREA. NR 17 TC 2 Z9 2 U1 0 U2 0 PU KOREAN PHYSICAL SOC PI SEOUL PA 635-4, YUKSAM-DONG, KANGNAM-KU, SEOUL 135-703, SOUTH KOREA SN 0374-4884 J9 J KOREAN PHYS SOC JI J. Korean Phys. Soc. PD JUL PY 1997 VL 31 IS 1 BP 108 EP 111 PG 4 WC Physics, Multidisciplinary SC Physics GA XL063 UT WOS:A1997XL06300028 ER PT J AU Hatay, FF OSullivan, PL Biringen, S Bandyopadhyay, PR AF Hatay, FF OSullivan, PL Biringen, S Bandyopadhyay, PR TI Numerical simulation of secondary flows in channels driven by applied Lorentz forces SO JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER LA English DT Article ID TURBULENT AB The effect of applied magnetohydrodynamic (Lorentz) forces on the flowfields in saltwater plane channel flow has been investigated by performing large-scale computer simulations. Direct numerical simulations of three-dimensional. time-dependent secondary how of an electroconducting fluid driven by Lorentz forces caused by applied electromagnetic fields have been performed, The computational model consists of a two-dimensional doubly periodic configuration of magnet and electrode microtiles flush-mounted on the lower surface of the channel. The resulting flowfields for low Reynolds number simulations reveal that the applied downward Lorentz force formed over the area between the magnet/electrode pairs causes the velocity perturbations to be confined to a very thin layer in the wall-normal direction, Thus, the design objective of localizing the Lorentz force close to the Hall is achieved. Lateral components of the Lorentz force also contribute significantly to the formation of the secondary vortical flowfield, Simulations were also carried out with a pulsatile Lorentz Force, The results show that this technique is a viable method of perturbing the how while reducing the power consumption and corrosion of the microtiles. C1 UNIV COLORADO,DEPT AEROSP ENGN SCI,BOULDER,CO 80309. USN,UNDERSEA WARFARE CTR,NEWPORT,RI 02841. NR 6 TC 2 Z9 2 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0887-8722 J9 J THERMOPHYS HEAT TR JI J. Thermophys. Heat Transf. PD JUL-SEP PY 1997 VL 11 IS 3 BP 446 EP 453 DI 10.2514/2.6260 PG 8 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA XL327 UT WOS:A1997XL32700017 ER PT J AU Ligrani, PM Ramsey, AE AF Ligrani, PM Ramsey, AE TI Film cooling from spanwise-oriented holes in two staggered rows SO JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT 40th International Gas Turbine and Aeroengine Congress and Exhibition CY JUN 05-08, 1995 CL HOUSTON, TX ID COMPOUND ANGLE ORIENTATIONS; RESULTS DOWNSTREAM; SINGLE ROW AB Adiabatic effectiveness and iso-energetic heat transfer coefficients are presented from measurements downstream of film-cooling holes inclined at 30 deg, with respect to the test surface in spanwise/normal planes. With this configuration, holes are spaced 3d apart in the spanwise direction and 4d in the streamwise direction in two staggered rows. Results are presented for an injectant to free-stream density ratio near 1.0, and injection blowing ratios from 0.5 to 1.5. Spanwise-averaged adiabatic effectiveness values downstream of the spanwise/normal plane holes are significantly higher than values measured downstream of simple angle holes for x/d < 25-70 ( depending on blowing ratio) when compared for the same normalized streamwise location, blowing ratio, and spanwise and streamwise hole spacings. Spanwise-averaged isoenergetic Stanton number ratios range between 1.0 and 1.41, increase with blowing ratio at each streamwise station, and show little variation with streamwise location for each value of blowing ratio tested. C1 USN,POSTGRAD SCH,DEPT MECH ENGN,MONTEREY,CA 93943. RP Ligrani, PM (reprint author), UNIV UTAH,DEPT MECH ENGN,CONVECT HEAT TRANSFER LAB,SALT LAKE CITY,UT 84112, USA. NR 17 TC 16 Z9 17 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0889-504X J9 J TURBOMACH JI J. Turbomach.-Trans. ASME PD JUL PY 1997 VL 119 IS 3 BP 562 EP 567 PG 6 WC Engineering, Mechanical SC Engineering GA XQ503 UT WOS:A1997XQ50300021 ER PT J AU Reinecke, TL Knipp, PA Walck, SN AF Reinecke, TL Knipp, PA Walck, SN TI Optical properties of semiconductor nanostructures SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 24th Annual Conference on the Physics and Chemistry of Semiconductor Interfaces (PCSI-24) CY JAN 12-15, 1997 CL RES TRIANGLE PK, NC ID QUANTUM WIRES AB Boundary element methods for calculating the single-particle electron and photon states of semiconductor quantum wires and quantum dots are discussed, and variational treatments for calculating exciton properties are given. Calculations of single-particle carrier states, of exciton binding energies and of confined photon states are compared with experimental data obtained on lithographically formed semiconductor wires and dots. (C) 1997 American Vacuum Society. C1 CHRISTOPHER NEWPORT UNIV,DEPT PHYS & COMP SCI,NEWPORT NEWS,VA 23606. RP Reinecke, TL (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 14 TC 4 Z9 4 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD JUL-AUG PY 1997 VL 15 IS 4 BP 1040 EP 1044 DI 10.1116/1.589389 PG 5 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA XT088 UT WOS:A1997XT08800047 ER PT J AU Koops, HWP Dobisz, E Urban, J AF Koops, HWP Dobisz, E Urban, J TI Novel lithography and signal processing with water vapor ions SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 24th Annual Conference on the Physics and Chemistry of Semiconductor Interfaces (PCSI-24) CY JAN 12-15, 1997 CL RES TRIANGLE PK, NC ID BEAM-INDUCED DEPOSITION AB A novel model is presented for the operation of field emission sources in air. Under this condition the cathode-anode distance is less than the mean free path for the particles emitted in air. Such conditions are encountered in scanning tunneling microscope lithography in air and in novel integrated microtriode tube devices designed to operate in air. In air, the presence of a high electric field gradient, produced at the tip, will cause the polar water molecules coating the surface to align with the field and move to the high field region. As a result, a Taylor cone of water, like that as it is observed with liquid metal ion sources, will form. The high electric field gradient at the Taylor cone, enhanced by the high dielectric constant, will produce a very finely focused beam of ions. We examine the case of water ion formation. With a positive tip bias, hydronium ions will form at electric fields of 1 V/nm. This is a factor of 4 smaller than that required to produce the field emission with electrons. The electric field distribution and the hydronium ion trajectories from a metal tip with a high permittivity material cone are calculated. The spot size of the ion beam on the substrate was 2.9 nm. A model for lithography, based on water ions, is presented. The model is applied to the design of a microtriode device for signal processing. The three-dimensional fabrication of such a device by e-beam induced chemical vapor deposition is demonstrated. (C) 1997 American Vacuum Society. [S0734-211X(97)03804-3]. C1 USN, RES LAB, WASHINGTON, DC 20375 USA. TH DARMSTADT, INST ANGEW PHYS, D-64289 DARMSTADT, GERMANY. RP DEUTSCH TELEKOM AG, TECHNOL ZENTRUM, D-64295 DARMSTADT, GERMANY. NR 17 TC 11 Z9 11 U1 0 U2 3 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD JUL-AUG PY 1997 VL 15 IS 4 BP 1369 EP 1372 DI 10.1116/1.589540 PG 4 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA XT088 UT WOS:A1997XT08800106 ER PT J AU Gnuechtel, MM Keyser, JS Greinwald, JH Postma, GN AF Gnuechtel, MM Keyser, JS Greinwald, JH Postma, GN TI Electrocautery versus carbon dioxide laser for uvulopalatoplasty in the treatment of snoring SO LARYNGOSCOPE LA English DT Article; Proceedings Paper CT Meeting of the Southern Section of the Laryngological-Rhinological-and-Otological-Society CY JAN 17, 1997 CL CAPTIVA ISLAND, FL SP Laryngol Rhinol & Otol Soc, So Sect ID OBSTRUCTIVE SLEEP-APNEA; ASSISTED UVULOPALATOPLASTY; UVULOPALATOPHARYNGOPLASTY AB Laser-assisted uvulopalatoplasty is a popular method for reducing snoring. Drawbacks are the large initial expense of the laser unit and related equipment and required safety precautions. The equipment required for electrocautery for cautery-assisted uvulopalatoplasty is significantly less expensive to obtain and operate compared with the carbon dioxide laser. Ninety-eight patients were randomly assigned to one of two treatment groups to undergo uvulopalatoplasty: one performed with the carbon dioxide laser and the other with electrocautery. We compared postoperative pain, time off work, efficacy, and the number of treatments required to achieve a satisfactory result. We found no statistically significant difference in any of these parameters between the two treatment groups (P > 0.05). Our data show that the use of the carbon dioxide laser offers no advantage over electrocautery in performing uvulopalatoplasty to treat snoring. C1 WAKE FOREST UNIV,BOWMAN GRAY SCH MED,DEPT OTOLARYNGOL,CTR VOICE DISORDERS,WINSTON SALEM,NC 27157. USN HOSP,DEPT OTOLARYNGOL HEAD & NECK SURG,PENSACOLA,FL. USN HOSP,DEPT OTOLARYNGOL HEAD & NECK SURG,CAMP LEJEUNE,NC. UNIV IOWA HOSP & CLIN,DEPT OTOLARYNGOL HEAD & NECK SURG,IOWA CITY,IA 52242. NR 29 TC 10 Z9 10 U1 0 U2 1 PU LIPPINCOTT-RAVEN PUBL PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 SN 0023-852X J9 LARYNGOSCOPE JI Laryngoscope PD JUL PY 1997 VL 107 IS 7 BP 848 EP 854 DI 10.1097/00005537-199707000-00003 PG 7 WC Medicine, Research & Experimental; Otorhinolaryngology SC Research & Experimental Medicine; Otorhinolaryngology GA XJ298 UT WOS:A1997XJ29800003 PM 9217118 ER PT J AU Sawyer, WB Ransom, B Bennett, RH AF Sawyer, WB Ransom, B Bennett, RH TI Geotechnical property variability of continental margin sediments: High-resolution vertical and lateral data from the northern California slope SO MARINE GEORESOURCES & GEOTECHNOLOGY LA English DT Article DE bioturbation; continental slope; geotechnical properties; Mendocino; California; oxygen minimum zone; physical properties; porosity; sediment variability; water content ID LONG-ISLAND SOUND; BENTHIC FLUXES; SEA-FLOOR; OCEAN AB High-resolution vertical and lateral gradients and variations in sediment mass physical properties were derived fi om measurements in box cores, on the scale of millimeters, tens of centimeters, and kilometers from typical, relatively broad areas of the northern California continental slope in the Cape Mendocino area at water depths from 380 to 940 m. Such data are important as a control on comparisons of different sediment suites, as well as providing limits for realistic flux calculations of dissolved inorganic and biochemical species and pollutants. The sediments studied have relatively constant organic carbon contents (OC similar or equal to 1.75 wt%) and bulk mineralogy. They range from silty sands (similar to 45% sand, 40% silt) to clayey silts (similar to 63% silt, similar to 35% clay) and are extensively bioturbated. Physical property variations between subcores (similar to 25 to 35 cm in length), taken from the same box core, increase with increasing clay content. For coarse-grained sediments, mean down-core differences in physical property values between related subcores are small, averaging 3.6% for water content, 4% for porosity, 0.026 Mg/m(3) for wet bulk density, and 0.1 for void ratio. Subcore variations for fine-grained sediments are generally significantly larger, averaging 9.8% for water content, 1.52% for porosity, 0.027 Mg/m(3) for wet bulk density, and 0.3 for void ratio (box core 125). Millimeter variations of physical properties from horizontal 12-cm-long subcores indicate a maximum range of lateral variation of 18.2% for water content, 8% for porosity, 0.14 Mg/m(3) for wet bulk density, and similar to 0.6 for void ratio. C1 UNIV CALIF SAN DIEGO,SCRIPPS INST OCEANOG,LA JOLLA,CA 92093. SEAPROBE INC,PICAYUNE,MS. RP Sawyer, WB (reprint author), USN,RES LAB,CODE 7431,STENNIS SPACE CTR,MS 39529, USA. NR 29 TC 7 Z9 7 U1 0 U2 2 PU TAYLOR & FRANCIS PI BRISTOL PA 1900 FROST ROAD, SUITE 101, BRISTOL, PA 19007-1598 SN 1064-119X J9 MAR GEORESOUR GEOTEC JI Mar. Geores. Geotechnol. PD JUL-SEP PY 1997 VL 15 IS 3 BP 283 EP 304 PG 22 WC Engineering, Ocean; Engineering, Geological; Oceanography; Mining & Mineral Processing SC Engineering; Oceanography; Mining & Mineral Processing GA XY930 UT WOS:A1997XY93000004 ER PT J AU Kee, A Matic, P Wolla, JM AF Kee, A Matic, P Wolla, JM TI A computational study of elongated pore interactions in a low density porous copper SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE pores; solid copper matrix; transverse constraint ID VOID LINKING; FRACTURE; SIMULATION AB A finite element investigation of an array of high aspect ratio pores under tension deformation was performed to evaluate geometric features affecting bulk yield, strain hardening and strength in a 'gasar' porous copper material of 21.5% pore volume fraction. The analysis simulated a planar triagonal array representing a central pore and its six nearest neighbors. Typical pore dimensions of 18 mu m in diameter, 108 mu m in length and 60 mu m transverse spacing between centers were used for the model. Local transverse constraint above and below groups of pores will vary due to the presence or absence of isolated pore free zones throughout the microstructure. Displacement boundary conditions were selected to evaluate the effect of zero, partial and full transverse constraint. The normalized load vs. normalized displacement results from the model are found to exceed that of the solid copper matrix by 89% for full transverse constraint and 16% for partial transverse constraint at peak normalized load, and 6% below that of the solid copper matrix for zero constraint at 0.20 normalized displacement. These results provide insight into the role of pore interactions and local geometric constraint on the comparatively high bulk strength observed in these materials. Full transverse constraint is also responsible for the deformation localization consistent with the appearance of the fracture surface. (C) 1997 Elsevier Science S.A. C1 USN,RES LAB,MECH MAT BRANCH,WASHINGTON,DC 20375. GEOCTR,FT WASHINGTON,MD 20744. USN,RES LAB,PHYS MET BRANCH,WASHINGTON,DC 20375. NR 22 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD JUL 1 PY 1997 VL 230 IS 1-2 BP 14 EP 24 DI 10.1016/S0921-5093(97)80110-4 PG 11 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA XM776 UT WOS:A1997XM77600002 ER PT J AU ZeislerMashl, KL Lograsso, TA AF ZeislerMashl, KL Lograsso, TA TI The occurrence and periodicity of oscillating peritectic microstructures developed during directional solidification SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article AB The layered microstructures that can form during plane-front directional solidification in peritectic systems were characterized quantitatively as a function of growth velocity using a Sn-Cd alloy. Layers were formed for an alloy composition outside of the two-phase peritectic region in the absence of longitudinal macrosegregation. The layers did not extend over the entire sample cross sections, so that the layered regions had a different composition than the alloy. Each of the two solids was found to be interconnected and continuous in three dimensions. The layer lengths and individual layer compositions did not vary with solidification distance. The average layer compositions were not a function of growth velocity and were approximately those at the peritectic temperature. This research was compared to the current model by Trivedi, which is based upon cyclic accumulation and depletion of solute in the liquid ahead of the interface linked to repeated nucleation events. The dependence of layer length on growth velocity predicted by the model was not obtained experimentally. The differences between results and predictions are related to the continuity of the two solids and the nonuniform cross-sectional composition in the Sn-Cd samples, which contradict assumptions of the model. A formation mechanism involving competitive lateral growth between the two solids at the solid-liquid interface would be more consistent with the current research. C1 IOWA STATE UNIV,USDA,AMES LAB,AMES,IA 50011. RP ZeislerMashl, KL (reprint author), USN,RES LAB,PHYS MET BRANCH,WASHINGTON,DC 20375, USA. NR 17 TC 10 Z9 11 U1 0 U2 1 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD JUL PY 1997 VL 28 IS 7 BP 1543 EP 1552 DI 10.1007/s11661-997-0216-1 PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA XL481 UT WOS:A1997XL48100014 ER PT J AU Corrigan, CM Zolensky, ME Dahl, J Long, M Weir, J Sapp, C Burkett, PJ AF Corrigan, CM Zolensky, ME Dahl, J Long, M Weir, J Sapp, C Burkett, PJ TI The porosity and permeability of chondritic meteorites and interplanetary dust particles SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID MICROMETEORITES; COMPONENTS AB We have investigated the porosity of a large number of chondritic interplanetary dust particles (IDPs) and meteorites by three techniques: standard liquid/gas flow techniques, a new, noninvasive ultrasonic technique, and image processing of backscattered images. The latter technique is obviously best-suited to sub-kilogram sized samples. We have also measured the gas and liquid permeabilities of some chondrites by two techniques: standard liquid/gas flow techniques, and a new, nondestructive pressure release technique. We find that chondritic IDPs have a somewhat bimodal porosity distribution. Peaks are present at 0 and 4% porosity; a tail then extends to 53%. Type 1-3 chondrite matrix porosities range up to 30%, with a peak at 2%. The bulk porosities for type 1-3 chondrites have the same approximate range as exhibited by the matrix, which indicates that other components of the bulk meteorites (including chondrules and aggregates) have the same average porosity as the matrix. These results reveal that the porosities of primitive materials at scales ranging from nanogram to kilogram are similar, which implies that similar accretion dynamics operated through 12 orders of size magnitude. Permeabilities of the investigated chondrites vary by several orders of magnitude, and there appears to be no simple dependence of permeability with degree of aqueous alteration, chondrite type or porosity. C1 LUNAR & PLANETARY INST,HOUSTON,TX 77058. NASA,LYNDON B JOHNSON SPACE CTR,HOUSTON,TX 77058. BEMIDJI STATE UNIV,BEMIDJI,MN 56601. CORE LABS INC,HOUSTON,TX 77040. LOCKHEED MARTIN SCI & ENGN CO,HOUSTON,TX 77058. USN,RES LAB,STENNIS SPACE CTR,MS 39529. NR 21 TC 65 Z9 65 U1 4 U2 10 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUL PY 1997 VL 32 IS 4 BP 509 EP 515 PG 7 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA XN352 UT WOS:A1997XN35200009 ER PT J AU Krowne, CM AF Krowne, CM TI Ferrite microstrip circulator 3D dyadic Green's function with perimeter interfacial walls and internal inhomogeneity SO MICROWAVE AND OPTICAL TECHNOLOGY LETTERS LA English DT Article DE planar circulator; nonreciprocal media; Green's function; electromagnetic fields AB Imperfect walls at the device perimeter are allowed. A new dyadic Green's function is found by specification of the source as a finite-length singularity in the z direction on the device boundary contour at location phi' and the use of mode matching. The new dyadic Green's function allows fields and s parameters to be found, dependent on the external material parameters. (C) 1997 John Wiley & Sons, Inc. RP Krowne, CM (reprint author), USN,RES LAB,DIV ELECT SCI & TECHNOL,MICROWAVE TECHNOL BRANCH,WASHINGTON,DC 20375, USA. NR 4 TC 4 Z9 4 U1 0 U2 0 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0895-2477 J9 MICROW OPT TECHN LET JI Microw. Opt. Technol. Lett. PD JUL PY 1997 VL 15 IS 4 BP 235 EP 242 PG 8 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA XE333 UT WOS:A1997XE33300014 ER PT J AU Hodur, RM AF Hodur, RM TI The Naval Research Laboratory's coupled ocean/atmosphere mesoscale prediction system (COAMPS) SO MONTHLY WEATHER REVIEW LA English DT Article ID TROPICAL CYCLONE MOTION; NUMERICAL-SIMULATION; COORDINATE TRANSFORMATION; MODEL; EQUATIONS; HURRICANES; DYNAMICS; LAYERS; HEAT AB The three-dimensional Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS) has been developed by the Naval Research Laboratory. COAMPS consists of an atmospheric data assimilation system comprising data quality control, analysis, initialization, and nonhydrostatic forecast model components, as well as a hydrostatic ocean model. The models can be integrated simultaneously so that the surface fluxes of heat, momentum, and moisture are exchanged across the air-water interface every time step. Optionally, either the atmospheric or ocean model can be used as a stand-alone system. The atmospheric component of COAMPS was used for operational support for the America(3) team in the 1995 America's Cup races. Results of these forecasts indicated the necessity of data assimilation to reduce model spinup in the first 6 h of the forecast. Accurate forecasts of the low-level wind in the coastal race area was accomplished by utilizing triply nested grids to attain the necessary high resolution to resolve the local wind patterns and the underlying surface terrain field. Two idealized simulations of a tropical cyclone were performed with COAMPS. In the first simulation, only the atmospheric model was used, assuming a fixed sea surface temperature (SST). A realistic structure developed with spiral bands of convection present outside the inner eyewall. These spiral bands occasionally contracted inward resulting in rapid fluctuations in the intensity of the tropical cyclone. In the second simulation, the ocean model was run simultaneously with the atmospheric model. The SST cooled over 8 degrees C over a small area within the radius of maximum winds, resulting in a much weaker system. However, there appeared to be little effect on the overall strength of the system, as measured by the tangential velocities outside the radius of maximum winds. RP Hodur, RM (reprint author), USN, RES LAB, MARINE METEOROL DIV, 7 GRACE HOPPER AVE, MONTEREY, CA 93943 USA. NR 53 TC 565 Z9 570 U1 1 U2 20 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD JUL PY 1997 VL 125 IS 7 BP 1414 EP 1430 DI 10.1175/1520-0493(1997)125<1414:TNRLSC>2.0.CO;2 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA XJ257 UT WOS:A1997XJ25700003 ER PT J AU Doyle, JD AF Doyle, JD TI The influence of mesoscale orography on a coastal jet and rainband SO MONTHLY WEATHER REVIEW LA English DT Article ID PAST 3-DIMENSIONAL OBSTACLES; MID-LATITUDE CYCLONES; MICROSCALE STRUCTURE; FRONTAL RAINBANDS; COLD FRONTS; FLOW; MOUNTAINS; MODEL; ALPS; PRECIPITATION AB The role of mesoscale orography along the central California coast in the development and evolution of a coastal jet and rainband is investigated using a high-resolution, triply nested, nonhydrostatic numerical model. Comparison of the model simulations, which use horizontal grid increments of 5 and 2 km on the inner computational meshes, with a coastal mesoscale observation network indicates that the finescale structure of the jet and rainband dynamics are adequately simulated, although phase and orientation errors occur. The observed and simulated near-surface winds have maximum speeds that exceed 22 m s(-1) and a direction nearly parallel to the coastline and topography. Force balance analysis indicates that blocking in the lowest 500 m and how over the coastal range above this layer contribute to mesoscale pressure perturbations, including pressure ridging upstream of the coastal mountains, which forces the ageostrophic dynamics of the coastal jet. Pressure perturbations associated with the topographic Flows induce a complex mesoscale response that adds rich mesoscale structure to the jet including a wake region that forms on the lee side of the coastal range that limits the horizontal scale of the jet. Sensitivity test results underscore the multiprocess character of the coastal dynamics and the importance of the coastal topography and differential frictional drag at the land-sea interface for the formation and amplification of the jet. The mesoscale response to steep coastal topography results in a 45% enhancement to the near-surface jet strength. The onshore movement of line convection at the leading edge of a weak front is impeded by steep coastal topography in both the radar observations and numerical simulations. Low-level blocking forces the rainband to emulate a wedge-shaped structure with a coastal jet that is dynamically trapped between the steep coastal topography and the front. RP Doyle, JD (reprint author), USN, RES LAB, MARINE METEOROL DIV, 7 GRACE HOPPER AVE, STOP 2, MONTEREY, CA 93943 USA. NR 50 TC 77 Z9 79 U1 1 U2 5 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD JUL PY 1997 VL 125 IS 7 BP 1465 EP 1488 DI 10.1175/1520-0493(1997)125<1465:TIOMOO>2.0.CO;2 PG 24 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA XJ257 UT WOS:A1997XJ25700006 ER PT J AU Holden, RA Thomas, RW AF Holden, RA Thomas, RW TI Eigenanalysis applied to the computer network of a combat suite SO NAVAL ENGINEERS JOURNAL LA English DT Article AB This paper presents a quantitative approach to the study of complex computer automated systems by using methods basic to the study of physical systems. These methods are applied to system-wide data collected from the computer network of the combat suite deployed on Aegis class surface combatants. The network consists of interconnected AN/UYK-43A standard Navy computers. Analysis is presented using data collected simultaneously and in real-time from each central processing unit of the network. The approach taken is to apply vector field theory to a covariance analysis of collected data. The system-wide characteristics of network data are interpreted using eigenvalues, eigenvectors, and eigenfunctions commonly used to describe physical systems. By these methods, dormant threads of the network architecture can be described in terms of real-time linearly independent internal processes. Correlation time of measured data is also discussed. RP Holden, RA (reprint author), USN,CTR SURFACE WARFARE,DAHLGREN DIV,DAHLGREN,VA 22448, USA. NR 4 TC 2 Z9 2 U1 0 U2 1 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD JUL PY 1997 VL 109 IS 4 BP 35 EP 46 PG 12 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XQ978 UT WOS:A1997XQ97800008 ER PT J AU Rengachary, SS Blount, J Heros, D Bowers, S Truwit, C AF Rengachary, SS Blount, J Heros, D Bowers, S Truwit, C TI Craniocephalic disproportion with increased intracranial pressure and brain herniation: A new clinical syndrome in anemic patients: Report of two cases SO NEUROSURGERY LA English DT Article DE anemia; brain herniation; raised intracranial pressure; thalassemia ID INTRATHORACIC EXTRAMEDULLARY HEMATOPOIESIS; CHRONIC TONSILLAR HERNIATION; DESCENDING TRANSTENTORIAL HERNIATION; MASSIVE HEMOTHORAX; DISPLACEMENT; MRI; CRANIOSYNOSTOSIS; COMPLICATIONS; HYDROCEPHALUS; CONSCIOUSNESS AB OBJECTIVE AND IMPORTANCE: We describe a new clinical syndrome in two patients with chronic anemia. The major manifestation of the syndrome is herniation of the brain resulting in death caused by longstanding craniocephalic disproportion. The disproportion was caused by extreme thickening of the cranium because of erythroid hyperplasia. CLINICAL PRESENTATION: Two patients with known chronic anemia presented with chronic increase in intracranial pressure with acute deterioration resulting in brain herniation. INTERVENTION: Despite maximum medical therapy, both patients died as a result of uncontrollable increase in intracranial pressure. CONCLUSION: Patients with chronic anemia presenting with progressive headaches should be monitored for this newly described clinical phenomenon. C1 UNIV MINNESOTA,HOSP & CLIN,DEPT RADIOL,MINNEAPOLIS,MN 55455. METHODIST HOSP,DEPT PATHOL,MINNEAPOLIS,MN. MT SINAI HOSP,DEPT NEUROL,MIAMI,FL. USN,MED CTR,DEPT NEUROSCI,SAN DIEGO,CA 92152. RP Rengachary, SS (reprint author), UNIV MINNESOTA,HOSP & CLIN,DEPT NEUROSURG,BOX 96,420 DELAWARE ST E,MINNEAPOLIS,MN 55455, USA. NR 40 TC 11 Z9 11 U1 0 U2 0 PU WILLIAMS & WILKINS PI BALTIMORE PA 351 WEST CAMDEN ST, BALTIMORE, MD 21201-2436 SN 0148-396X J9 NEUROSURGERY JI Neurosurgery PD JUL PY 1997 VL 41 IS 1 BP 297 EP 303 DI 10.1097/00006123-199707000-00054 PG 7 WC Clinical Neurology; Surgery SC Neurosciences & Neurology; Surgery GA XH585 UT WOS:A1997XH58500152 PM 9218323 ER PT J AU Colson, WB AF Colson, WB TI Short wavelength free electron lasers in 1996 SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 18th International Free-Electron-Laser Conference CY AUG 26-30, 1996 CL ROME, ITALY SP Italian Natl Agcy New Technol Energy & Environm ID UVSOR STORAGE-RING; IR FEL PROJECT; SUPERCONDUCTING LINAC; SPONTANEOUS EMISSION; RACETRACK MICROTRON; TEST-FACILITY; INFRARED FEL; BEIJING FEL; FELICITA-I; VUV-FEL RP Colson, WB (reprint author), USN,POSTGRAD SCH,DEPT PHYS,MONTEREY,CA 93943, USA. NR 49 TC 9 Z9 10 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JUL 1 PY 1997 VL 393 IS 1-3 BP 6 EP 8 DI 10.1016/S0168-9002(97)00418-X PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA XV603 UT WOS:A1997XV60300003 ER PT J AU Freund, HP Granatstein, VL AF Freund, HP Granatstein, VL TI Long wavelength free electron lasers in 1996 SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 18th International Free-Electron-Laser Conference CY AUG 26-30, 1996 CL ROME, ITALY SP Italian Natl Agcy New Technol Energy & Environm ID RADIATION; WIGGLER; DIAGNOSTICS; OPERATION; MASER; BEAM; FEM AB A summary of the current status and most important future directions for long wavelength (greater than or equal to 0.5 mm) free-electron lasers is presented. The distinction between long and short wavelengths is a natural one since different physical processes may be important. Space-charge effects may be important for the high currents typically employed at long wavelengths, and the dominant interaction mechanism is often coherent Raman scattering. In addition, dispersion due to the dielectric effects and finite transverse dimensions in the drift tubes and cavities are important at longer wavelengths. The principal goals at long wavelengths are to achieve much higher average powers with good overall efficiency in a compact design, and the highest average power produced in an FEL to date (36 W) has been recorded in the Ku-band. C1 USN,RES LAB,WASHINGTON,DC 20375. UNIV MARYLAND,COLLEGE PK,MD 20742. RP Freund, HP (reprint author), SCI APPLICAT INT CORP,1710 GOODRIDGE DR,MCLEAN,VA 22102, USA. NR 38 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JUL 1 PY 1997 VL 393 IS 1-3 BP 9 EP 12 DI 10.1016/S0168-9002(97)00419-1 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA XV603 UT WOS:A1997XV60300004 ER PT J AU Colson, WB AF Colson, WB TI Theory of high-gain free-electron lasers SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 18th International Free-Electron-Laser Conference CY AUG 26-30, 1996 CL ROME, ITALY SP Italian Natl Agcy New Technol Energy & Environm DE free electron laser; X-rays ID AMPLIFIED-SPONTANEOUS-EMISSION; LINEAR WAVE-EQUATION; TESLA-TEST-FACILITY; NOISE; FEL; FLUCTUATIONS; EXTRACTION; EFFICIENCY; REGIME; SASE AB A powerful, coherent X-ray source may require a high-gain free-electron laser that makes use of self-amplified spontaneous emission. High gain can be achieved by using a combination of high peak current and a long undulator. The theoretical description of the high-gain FEL starts from the Lorentz-Maxwell equations solved self-consistently. RP Colson, WB (reprint author), USN,POSTGRAD SCH,DEPT PHYS,MONTEREY,CA 93943, USA. NR 24 TC 4 Z9 4 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JUL 1 PY 1997 VL 393 IS 1-3 BP 82 EP 85 DI 10.1016/S0168-9002(97)00432-4 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA XV603 UT WOS:A1997XV60300018 ER PT J AU Roberson, CW Hafizi, B AF Roberson, CW Hafizi, B TI Free electron laser beam quality - from Castelgandolfo to Rome SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 18th International Free-Electron-Laser Conference CY AUG 26-30, 1996 CL ROME, ITALY SP Italian Natl Agcy New Technol Energy & Environm ID EMITTANCE AB Since the Castelgandolfo FEL conference photo injectors and advances in beam transport has lead to many orders of magnitude improvement in beam brightness as well as our understanding of what constitutes a high-quality beam. We find that beam compression may increase brightness, but not beam quality; and that, when the relation lambda = pi epsilon is satisfied, the FEL is well into the kinetic regime of operation. A good measure of beam quality is the scaled thermal velocity. In some cases space charge may improve beam quality. C1 USN,RES LAB,DIV PLASMA PHYS,WASHINGTON,DC 20375. ICARUS RES INC,BETHESDA,MD 20824. RP Roberson, CW (reprint author), OFF NAVAL RES,DIV PHYS SCI,ARLINGTON,VA 22217, USA. NR 9 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JUL 1 PY 1997 VL 393 IS 1-3 BP 242 EP 244 DI 10.1016/S0168-9002(97)00485-3 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA XV603 UT WOS:A1997XV60300052 ER PT J AU Small, DW Wong, RK Colson, WB Armstead, RL AF Small, DW Wong, RK Colson, WB Armstead, RL TI Free electron lasers with short Rayleigh length SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 18th International Free-Electron-Laser Conference CY AUG 26-30, 1996 CL ROME, ITALY SP Italian Natl Agcy New Technol Energy & Environm AB To decrease power loading on cavity mirrors, a Gaussian mode with a very short Rayleigh length could be employed. We study the physics of the FEL interaction while shortening the Rayleigh length in the FEL oscillator. The results can be applied to the Industrial Laser Consortium's UV FEL and to high average power FELs in general. RP Small, DW (reprint author), USN,POSTGRAD SCH,DEPT PHYS,MONTEREY,CA 93943, USA. NR 3 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JUL 1 PY 1997 VL 393 IS 1-3 BP 262 EP 264 DI 10.1016/S0168-9002(97)00488-9 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA XV603 UT WOS:A1997XV60300056 ER PT J AU Freund, HP Nguyen, K Pershing, DE AF Freund, HP Nguyen, K Pershing, DE TI Theory of a ubitron in a corrugated waveguide SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 18th International Free-Electron-Laser Conference CY AUG 26-30, 1996 CL ROME, ITALY SP Italian Natl Agcy New Technol Energy & Environm AB A K-a band ubitron is currently under development at NRL using a corrugated waveguide and a helical wiggler. The corrugated waveguide is used for low-voltage operation. A 3-D nonlinear formulation has been derived, and a simulation code TARANTULA has been developed. The model treats HE and EH modes in the vacuum waveguide. No wiggler average is imposed on the electron dynamics. Preliminary calculations indicate that 20% bandwidth operation in K-a band is possible at voltages of about 90 kV with a 7-8 mm period wiggler generating a 500-600 G transverse magnetic field. Detailed results of the theory and simulation will be presented. C1 USN,RES LAB,WASHINGTON,DC 20357. KN RES,SILVER SPRING,MD 20906. MISSION RES CORP,NEWINGTON,VA 22122. NR 3 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JUL 1 PY 1997 VL 393 IS 1-3 BP 304 EP 307 DI 10.1016/S0168-9002(97)00498-1 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA XV603 UT WOS:A1997XV60300066 ER PT J AU Hill, RA Crean, DH Doiron, DR McDonald, TJ Liaw, LH Ghosheh, F Hamilton, A Berns, MW AF Hill, RA Crean, DH Doiron, DR McDonald, TJ Liaw, LH Ghosheh, F Hamilton, A Berns, MW TI Photodynamic therapy for antifibrosis in a rabbit model of filtration surgery SO OPHTHALMIC SURGERY AND LASERS LA English DT Article; Proceedings Paper CT 1995 Annual Meeting of the Association-for-Research-in-Vision-and-Ophthalmology CY MAY 14-19, 1995 CL FT LAUDERDALE, FL SP Assoc Res Vis & Ophthalmol ID GLAUCOMA FILTERING SURGERY; MITOMYCIN-C; TRABECULECTOMY; 5-FLUOROURACIL; TOXICITY; PHOTOSENSITIZERS; MACULOPATHY; FIBROBLASTS; PHOTOFRIN; HYPOTONY AB BACKGROUND AND OBJECTIVE: The purpose of this pilot study was to investigate the use of photodynamic therapy (PDT) using tin ethyl etiopurpurin (SnET2) as an adjunctive antifibrotic therapy for filtering surgery in a rabbit model. MATERIALS AND METHODS: The pharmacokinetics of SnET2 were established by intravenous (1 mg/kg) and subconjunctival (25, 50, or 75 mu g) injections and compared with controls. Intravenous and subconjunctival SnET2 injections were given prior to posterior lip sclerectomies followed by postoperative laser irradiation (664 +/- 7 nm; 100 mW/cm(2); 30 J/cm(2)). Antifibrotic efficacy was established by clinical response and histologic examination. RESULTS: After subconjunctival injections, large areas of avascular conjunctiva were produced and filtering bleb survival was prolonged. No effect was found for intravenously administered photosensitizer followed by light irradiation. CONCLUSIONS: PDT may be an alternative antifibrotic therapy for filtration surgery that does not use chemotherapeutic agents or ionizing radiation. Multiple parameters (light, drug dose, irradiation area) may be manipulated to improve predictability of the antifibrotic effect. C1 UNIV CALIF IRVINE,BECKMAN LASER INST & MED CLIN,IRVINE,CA 92715. PDT INC,SANTA BARBARA,CA. USN,EL TORO MARINE CORPS AIR STN,SANTA ANA,CA. RP Hill, RA (reprint author), UNIV CALIF IRVINE,DEPT OPHTHALMOL,1 MED PLAZA DR,IRVINE,CA 92717, USA. FU NCI NIH HHS [R01CA32248]; NCRR NIH HHS [RR01192] NR 25 TC 9 Z9 12 U1 0 U2 0 PU SLACK INC PI THOROFARE PA 6900 GROVE RD, THOROFARE, NJ 08086 SN 0022-023X J9 OPHTHALMIC SURG LAS JI Ophthalmic Surg. Lasers PD JUL PY 1997 VL 28 IS 7 BP 574 EP 581 PG 8 WC Ophthalmology; Surgery SC Ophthalmology; Surgery GA XK368 UT WOS:A1997XK36800006 PM 9243661 ER PT J AU Fonda, RW Vandermeer, RA AF Fonda, RW Vandermeer, RA TI Crystallography and microstructure of TaRu SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID OMEGA-PHASE AB The solid-state phase transformations and crystallography of equiatomic TaRu were examined by conventional and in-situ high-temperature transmission electron microscopy, with complementary experiments using X-ray diffraction and dilatometry. This alloy undergoes two displacive phase transformations on cooling from the high-temperature B2-ordered cubic phase. The high-temperature cubic-to-tetragonal transformation produces a highly twinned microstructure similar to that observed in many shape memory effect alloys. The phase produced by the low-temperature transformation was shown by detailed microdiffraction to have a monoclinic symmetry rather than the orthorhombic symmetry which had been previously reported. The structure of this monoclinic lattice indicates the possibility of an omega-like transformation in this alloy. RP Fonda, RW (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 14 TC 29 Z9 32 U1 0 U2 2 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD JUL PY 1997 VL 76 IS 1 BP 119 EP 133 PG 15 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA XJ782 UT WOS:A1997XJ78200007 ER PT J AU Bermudez, VM AF Bermudez, VM TI Structure and properties of cubic silicon carbide (100) surfaces: A review SO PHYSICA STATUS SOLIDI B-BASIC RESEARCH LA English DT Review ID SCANNING-TUNNELING-MICROSCOPY; ENERGY ELECTRON-DIFFRACTION; ATOMIC-LAYER EPITAXY; SOFT-X-RAY; BETA-SIC(100) SURFACE; TERMINATED BETA-SIC(001); GROWTH; RECONSTRUCTION; SPECTROSCOPY; SI AB A review is presented of recent experimental and theoretical work on the structure and properties of the clean, ordered and well-characterized (100) surfaces of cubic SiC. RP Bermudez, VM (reprint author), USN,RES LAB,DIV ELECT SCI & TECHNOL,WASHINGTON,DC 20375, USA. NR 92 TC 128 Z9 129 U1 3 U2 30 PU AKADEMIE VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0370-1972 J9 PHYS STATUS SOLIDI B JI Phys. Status Solidi B-Basic Res. PD JUL PY 1997 VL 202 IS 1 BP 447 EP 473 DI 10.1002/1521-3951(199707)202:1<447::AID-PSSB447>3.0.CO;2-I PG 27 WC Physics, Condensed Matter SC Physics GA XL897 UT WOS:A1997XL89700024 ER PT J AU Kresin, VZ Bill, A Wolf, SA Ovchinnikov, YN AF Kresin, VZ Bill, A Wolf, SA Ovchinnikov, YN TI Unconventional isotope effects in superconductors SO PHYSICAL REVIEW B LA English DT Article ID CRITICAL MAGNETIC-FIELD; NORMAL-STATE; APEX-OXYGEN; CU-O; YBA2CU3O6+X; BA AB The value of the isotope coefficient could be greatly affected by a number of factors not related to the lattice dynamics. Among them are magnetic scattering, the presence Of a normal film (proximity effect), End nonadiabaticity (dynamic Jahn-Teller effect). The results are in good agreement with existing experimental data for oxygen isotope substitution (O-16-->O-18) in the YBa2Cu3O7-delta, Y1-xPrxBa2Cu3O7-delta, YBa2(Cu1-xZnx)(3)O7-delta compounds. In addition, we make several predictions related to conventional as well as to high-T-c materials. C1 USN, RES LAB, WASHINGTON, DC 20375 USA. LD LANDAU THEORET PHYS INST, MOSCOW 11733V, RUSSIA. RP Kresin, VZ (reprint author), UNIV CALIF BERKELEY, LAWRENCE BERKELEY LAB, BERKELEY, CA 94720 USA. RI Wolf, Stuart/A-7513-2009 NR 36 TC 41 Z9 41 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD JUL 1 PY 1997 VL 56 IS 1 BP 107 EP 110 DI 10.1103/PhysRevB.56.107 PG 4 WC Physics, Condensed Matter SC Physics GA XJ272 UT WOS:A1997XJ27200028 ER PT J AU Broughton, JQ Meli, CA Vashishta, P Kalia, RK AF Broughton, JQ Meli, CA Vashishta, P Kalia, RK TI Direct atomistic simulation of quartz crystal oscillators: Bulk properties and nanoscale devices SO PHYSICAL REVIEW B LA English DT Article ID ACOUSTIC-WAVE MICROSENSORS; ALPHA-QUARTZ; MOLECULAR-DYNAMICS; LATTICE-DYNAMICS; CANONICAL ENSEMBLE; SILICA AB Current experimental research aims to reduce the size of quartz crystal oscillators into the submicrometer range. Devices then comprise multimillion atoms and operating frequencies will be in the gigahertz regime. Such characteristics make direct atomic scale simulation feasible using large scale parallel computing. Here, we describe molecular-dynamics simulations on bulk and nanoscale device systems focusing on elastic constants and flexural frequencies. Here we find (a) in order to achieve elastic constants within 1% of those of the bulk requires approximately one million atoms; precisely the experimental regime of interest; (b);differences from continuum mechanical frequency predictions are observable for 17 nm devices; (c) devices with 1% defects exhibit dramatic anharmonicity. A subsequent paper describes the direct atomistic simulation of operating characteristics of a micrometer scale device. A PAPS cosubmission gives algorithmic details. C1 LOUISIANA STATE UNIV,DEPT PHYS,BATON ROUGE,LA 70803. RP Broughton, JQ (reprint author), USN,RES LAB,COMPLEX SYST THEORY BRANCH,WASHINGTON,DC 20375, USA. NR 23 TC 92 Z9 94 U1 1 U2 10 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD JUL 1 PY 1997 VL 56 IS 2 BP 611 EP 618 DI 10.1103/PhysRevB.56.611 PG 8 WC Physics, Condensed Matter SC Physics GA XL827 UT WOS:A1997XL82700024 ER PT J AU Triandaf, I Schwartz, IB AF Triandaf, I Schwartz, IB TI Karhunen-Loeve mode control of chaos in a reaction-diffusion process SO PHYSICAL REVIEW E LA English DT Article ID TRACKING UNSTABLE ORBITS; SYSTEMS; STABILIZATION; DYNAMICS; PATTERNS; STATES; LASER AB We introduce a chaos control method that stabilizes unstable states of a spatiotemporal process based on analyzing the dynamics of the main coherent structure in the data represented bg the highest energy Karhunen-Loeve mode. The problem is then reduced to the application of embedding techniques to the control of a time series given by the amplitude of a dominant spatial mode. The algorithm is applied to a reaction-diffusion process where we stabilize an unstable orbit inside a chaotic regime. One advantage of the control procedure is that it is independent of sensor placement. Furthermore, we find the desired control state is achieved exponentially, and the procedure fan be applied directly to experimental data. C1 SCI APPLICAT INT CORP,APPL PHYS OPERAT,MCLEAN,VA 22102. RP Triandaf, I (reprint author), USN,RES LAB,SPECIAL PROJECT NONLINEAR SCI,DIV PLASMA PHYS,CODE 6700-3,WASHINGTON,DC 20375, USA. RI Schwartz, Ira/A-8073-2009 NR 31 TC 12 Z9 12 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD JUL PY 1997 VL 56 IS 1 BP 204 EP 212 DI 10.1103/PhysRevE.56.204 PN A PG 9 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA XM375 UT WOS:A1997XM37500034 ER PT J AU Tsang, KY Ngai, KL AF Tsang, KY Ngai, KL TI Dynamics of relaxing systems subjected to nonlinear interactions SO PHYSICAL REVIEW E LA English DT Article ID DISSIPATIVE SYSTEMS; NEUTRON-SCATTERING; STRANGE ATTRACTORS; PHASE-SPACE; DISTRIBUTIONS; BEHAVIOR AB The combination of the Fermi map system and half a stadium is studied to determine the effect of additional nonlinearity in the well known Fermi acceleration problem. The relaxation in the Fermi-stadium map with different R's is compared to that in the Fermi map. The relaxation is found retarded for different values of R. After a crossover time, the Fermi relaxation can be approximated by an exponential function, while the Fermi-stadium relaxation can be approximated by a stretched-exponential function. The fractional exponent beta decreases further from unity with increasing nonlinearity. The result bears strong similarity to the basic features suggested by the coupling model and seen experimentally in glass-forming materials by neutron scattering. C1 SCI APPLICAT INT CORP,MCLEAN,VA 22102. RP Tsang, KY (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 22 TC 90 Z9 91 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD JUL PY 1997 VL 56 IS 1 BP R17 EP R20 DI 10.1103/PhysRevE.56.R17 PN A PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA XM375 UT WOS:A1997XM37500005 ER PT J AU Uhm, HS Hendricks, KJ Arman, MJ Bowers, L Hackett, KE Spencer, TA Coleman, PD Lemke, RW AF Uhm, HS Hendricks, KJ Arman, MJ Bowers, L Hackett, KE Spencer, TA Coleman, PD Lemke, RW TI A nonlinear theory of relativistic klystrons connected to a coaxial waveguide SO PHYSICS OF PLASMAS LA English DT Article ID ELECTRON-BEAM AB A self-consistent nonlinear theory of current modulation in an electron beam propagating through relativistic klystrons connected to a coaxial waveguide is developed. A theoretical model of the beam-energy increase Delta gamma near the extraction cavity is also developed, based on the self-potential depression. The potential depression kappa can be significantly reduced in the vicinity of the extraction cavity from its value at the injection point. In appropriate system parameters, the kinetic-energy increase can easily be more than 50 keV, thereby eliminating the possibility of virtual cathode in the extraction cavity. Properties of the current modulation in a klystron are also investigated, assuming that a regular cylindrical waveguide is connected to a coaxial waveguide at the propagation distance z = z(1). Due to proximity of a grounded conductor, the beam's potential depression kappa in the coaxial region is considerably less than that in the regular region. It is shown in the present analysis that amplitude of the current modulation increases drastically as the coaxial inner-conductor approaches the driving cavity. Moreover, the-amplitude of the current modulation in the coaxial region changes slowly in comparison with that in the regular region. C1 USAF,PHILLIPS LAB,KIRTLAND AFB,NM 87117. SANDIA NATL LABS,ALBUQUERQUE,NM 87185. RP Uhm, HS (reprint author), USN,CTR SURFACE WARFARE,CARDEROCK DIV,9500 MACARTHUR BLVD,BETHESDA,MD 20817, USA. NR 5 TC 1 Z9 1 U1 1 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JUL PY 1997 VL 4 IS 7 BP 2691 EP 2696 DI 10.1063/1.872355 PG 6 WC Physics, Fluids & Plasmas SC Physics GA XH863 UT WOS:A1997XH86300039 ER PT J AU Murray, JN AF Murray, JN TI Electrochemical test methods for evaluating organic coatings on metals: an update. Part II: single test parameter measurements SO PROGRESS IN ORGANIC COATINGS LA English DT Review DE electrochemical test methods; organic coatings on metals; single test parameter measurements ID PIGMENT VOLUME CONCENTRATION; IMPEDANCE SPECTROSCOPY DATA; COATED STEEL; PAINT FILMS; CORROSION-RESISTANCE; PROTECTIVE COATINGS; WATER-UPTAKE; PERFORMANCE; PREDICTION; BEHAVIOR AB The status of evaluating organic coated metals utilizing electrochemical means was reviewed for the period of 1988-1994. The general improvements in the overall technology are presented in three sections. Part I covers the test cell configurations, changes in testing approaches and a brief survey of measurement equipment. Part II presents the test methods involving a single lest parameter such as the panel potential relative to a reference electrode, electrochemical voltage and/or current noise, as well as the de resistance of the coating on the metal substrate. Multiple test parameter measurements such as potentiodynamic curves and electrochemical impedance spectroscopy are covered in Part III. Although the majority of data were taken from the literature, some supplementary data are included from NSWCCD studies. Published by Elsevier Science S.A. C1 USN, Ctr Surface Warfare, Carderock Div, Corros Branch W, Bethesda, MD 20817 USA. RP Murray, JN (reprint author), USN, Ctr Surface Warfare, Carderock Div, Corros Branch W, Code 613, Bethesda, MD 20817 USA. NR 111 TC 24 Z9 24 U1 1 U2 9 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0300-9440 J9 PROG ORG COAT JI Prog. Org. Coat. PD JUL PY 1997 VL 31 IS 3 BP 255 EP 264 DI 10.1016/S0300-9440(97)00084-2 PG 10 WC Chemistry, Applied; Materials Science, Coatings & Films SC Chemistry; Materials Science GA YP455 UT WOS:000071278500009 ER PT J AU West, JC Sletten, MA AF West, JC Sletten, MA TI Multipath EM scattering from breaking ocean waves at grazing incidence SO RADIO SCIENCE LA English DT Article ID POLARIMETRIC RADAR; SEA-SURFACE; RESOLUTION; ANGLES; MODEL AB The electromagnetic scattering from a breaking water wave with near grazing illumination has been examined using both experimental measurement and numerical calculation. The scattering from a metal model of a breaking wave of 1.2 m wavelength was characterized at grazing angles ranging from 0 degrees to 25 degrees and at frequencies ranging from 6 GHz to 12 GHz. Strong multipath interference is observed in the vertical polarization (VV) backscatter and much weaker interference is seen in the horizontal polarization (HH) backscatter. Scattering from the wave profile both with and without the breaking plume shows that the plume is the dominant scattering feature. Numerical calculation of the scattering from modified surface profiles shows that the interference is due to multipath scattering from the plume and front face of the wave. HH interference is substantially smaller than that of VV because the scatter from the plume in the multipath direction (toward the front face) is greatly reduced owing to the conducting surface boundary conditions. The relative levels of the plume and expected distributed-surface scattering are consistent with the wave-tank measurement of horizontally polarized sea spikes from breaking waves of this scale. C1 USN,RES LAB,WASHINGTON,DC 20375. RP West, JC (reprint author), OKLAHOMA STATE UNIV,SCH ELECT & COMP ENGN,202 ES,STILLWATER,OK 74078, USA. NR 25 TC 16 Z9 16 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0048-6604 J9 RADIO SCI JI Radio Sci. PD JUL-AUG PY 1997 VL 32 IS 4 BP 1455 EP 1467 DI 10.1029/97RS00909 PG 13 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA XM795 UT WOS:A1997XM79500011 ER PT J AU Page, DL Austen, JR AF Page, DL Austen, JR TI Comparison of tomographic and conventional methods for resolution of the constant of integration SO RADIO SCIENCE LA English DT Article; Proceedings Paper CT 8th International Ionospheric Effects Symposium (IES-96) CY MAY 07-09, 1996 CL ALEXANDRIA, VA SP USN, Off Naval Res, USAF, Phillips Lab, USA, CECOM, USN, Naval C2 Ocean Surveillance Ctr, RDT&E Div, Voice America, Fed Commun Commiss ID IONOSPHERIC TOMOGRAPHY AB Computerized ionospheric tomography (CIT) is an imaging technique that produces a two-dimensional image of the electron density in the ionosphere. This technique uses total electron content (TEC) measurements from multiple ground stations as input data to computerized tomography (CT) algorithms. Unfortunately, the TEC data suffer from ambiguities that are introduced during the measurement process. Ionosphere researchers model these ambiguities as an unknown constant which is added to the true TEC data. This is known as the constant of integration problem. Traditional methods for resolving this problem, such as the single- and two-station methods, are based on ionospheric models and may perform poorly when the true ionospheric structure differs greatly from the model. This paper introduces a new method to estimate the unknown constants. The method, called the reconstruction residuals method, does not make use of ionospheric models but is based on the correlation between the unknown constants and the residual errors from a CIT reconstruction. Simulation results using this method are compared with the traditional estimation methods. Results from the new method compare favorably with results from the traditional methods. C1 TENNESSEE TECHNOL UNIV,COOKEVILLE,TN 38505. RP Page, DL (reprint author), USN,CTR SURFACE WARFARE,DAHLGREN,VA 22448, USA. OI Page, David/0000-0003-3353-4300 NR 16 TC 0 Z9 0 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0048-6604 J9 RADIO SCI JI Radio Sci. PD JUL-AUG PY 1997 VL 32 IS 4 BP 1645 EP 1656 DI 10.1029/97RS00839 PG 12 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA XM795 UT WOS:A1997XM79500028 ER PT J AU Stanley, MD Denison, GL AF Stanley, MD Denison, GL TI General case of the day SO RADIOGRAPHICS LA English DT Article; Proceedings Paper CT 82nd Scientific Assembly and Annual Meeting of the Radiological-Society-of-North-America CY DEC 01-06, 1996 CL CHICAGO, IL SP Radiol Soc N Amer DE femur, fractures; fractures, stress ID LONGITUDINAL STRESS-FRACTURES; TIBIA C1 USN,MED CTR,DEPT RADIOL,SAN DIEGO,CA 92134. USN,MED CTR,DEPT CLIN INVEST,SAN DIEGO,CA 92134. NR 11 TC 5 Z9 5 U1 0 U2 0 PU RADIOLOGICAL SOC NORTH AMER PI EASTON PA 20TH AND NORTHAMPTON STS, EASTON, PA 18042 SN 0271-5333 J9 RADIOGRAPHICS JI Radiographics PD JUL-AUG PY 1997 VL 17 IS 4 BP 1007 EP 1010 PG 4 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA XH282 UT WOS:A1997XH28200020 PM 9225399 ER PT J AU Sorathia, U Lyon, R OHlemiller, T Grenier, A AF Sorathia, U Lyon, R OHlemiller, T Grenier, A TI A review of fire test methods and criteria for composites SO SAMPE JOURNAL LA English DT Editorial Material C1 FED AVIAT ADMIN,WASHINGTON,DC 20591. UNIV COLORADO,NIST,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. RP Sorathia, U (reprint author), USN,CTR SURFACE WARFARE,CARDEROCK DIV,WASHINGTON,DC 20350, USA. NR 26 TC 19 Z9 19 U1 0 U2 2 PU SAMPE PUBLISHERS PI COVINA PA 1161 PARKVIEW DRIVE, COVINA, CA 91722 SN 0091-1062 J9 SAMPE J JI Sampe J. PD JUL-AUG PY 1997 VL 33 IS 4 BP 23 EP 31 PG 9 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary SC Engineering; Materials Science GA XK810 UT WOS:A1997XK81000004 ER PT J AU Sorathia, U Dapp, T AF Sorathia, U Dapp, T TI Structural performance of glass/vinylester composites at elevated temperatures SO SAMPE JOURNAL LA English DT Article AB Organic polymer matrix based fiber reinforced composite materials undergo viscoelastic transitions followed by reversible and irreversible thermal damage when exposed to evaluated temperature due to shipboard fires. To determine the limits of composite structural performance at elevated temperatures. Dynamic Mechanical Thermal Analysis (DMTA) was performed. In the first step, glass reinforced vinylester composite panels were isothermally aged and tested in DMTA for storage (E') and loss (E'') moduli for a period of eight hours at 77, 150, 200, 250, 300, 400, 500, and 600 degrees F (25, 66, 93, 121, 149, 204, 260, 316 degrees C) respectively. Data show that E' decreases at subsequently increasing temperatures until 200 degrees F. A significant drop in E' takes place between 200 and 250 degrees F followed by a catastrophic drop between 250 and 300 degrees F. Thus, 206 degrees F represents the upper threshold of operating temperature for unprotected glass reinforced vinylester load bearing composite structures. In the second step, all samples, previously isothermally aged at various temperatures, were cooled to room temperature and retested. Data show that samples previously isothermally aged up to 150 degrees F for a period of eight hours, and subsequently cooled to room temperature, do not exhibit thermal damage and recover all of their original structural performance. Beyond 150 degrees F and up to 406 degrees F, the glass/vinylester samples begin to exhibit thermal damage. However, load bearing structures exposed to these temperatures up to 400 degrees F still retain up to 70 percent of original flexible properties. Beyond 400 degrees F, the glass/vinylesters samples suffer significant thermal damage and begin to lose load bearing viability as a composite structure. This can be further observed in dynamic scans for loss factor (tan delta) obtained from DMTA testing of previously isothermally aged samples. At temperatures of isothermally aging beyond 400 degrees F, vinylester resin exhibits chemical breakdown as evidenced by the loss of matrix resin viscoelasticity. These scans show that vinylester resin is no longer capable of transferring the load to the fiber. As such, load bearing structures exposed to isothermal aging for a period of eight hours at temperatures above 400 degrees F may necessitate significant damage repair or even replacement of composite load bearing structure. RP Sorathia, U (reprint author), USN,CTR SURFACE WARFARE,CARDEROCK DIV,BETHESDA,MD 20814, USA. NR 20 TC 2 Z9 2 U1 1 U2 2 PU SAMPE PUBLISHERS PI COVINA PA 1161 PARKVIEW DRIVE, COVINA, CA 91722 SN 0091-1062 J9 SAMPE J JI Sampe J. PD JUL-AUG PY 1997 VL 33 IS 4 BP 53 EP 58 PG 6 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary SC Engineering; Materials Science GA XK810 UT WOS:A1997XK81000009 ER PT J AU Kostoff, RN AF Kostoff, RN TI Citation analysis cross-field normalization: A new paradigm SO SCIENTOMETRICS LA English DT Article AB A new paradigm for comparing quality of published papers across different disciplines has been proposed. This method uses a figure of merit of the ratio of actual citations received to the potential maximum number of citations that could have been received. It is analogous to approaches used to compare performance in physical systems, and appears intrinsically more useful than present approaches. RP Kostoff, RN (reprint author), OFF NAVAL RES,800 N QUINCY ST,ARLINGTON,VA 22217, USA. NR 3 TC 13 Z9 13 U1 3 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0138-9130 J9 SCIENTOMETRICS JI Scientometrics PD JUL-AUG PY 1997 VL 39 IS 3 BP 225 EP 230 DI 10.1007/BF02458527 PG 6 WC Computer Science, Interdisciplinary Applications; Information Science & Library Science SC Computer Science; Information Science & Library Science GA XW523 UT WOS:A1997XW52300001 ER PT J AU Doyle, JG OShea, E Erdelyi, R Dere, KP Socker, DG Keenan, FP AF Doyle, JG OShea, E Erdelyi, R Dere, KP Socker, DG Keenan, FP TI Nonthermal velocities in the solar transition zone and corona SO SOLAR PHYSICS LA English DT Article ID HIGH-RESOLUTION TELESCOPE; MAGNETIC-FLUX TUBES; RESONANT ABSORPTION; ALFVEN WAVES; QUIET-SUN; LINES; SPECTROGRAPH; ENERGY; REGIONS; SPECTRA AB Nonthermal velocities are presented for spectral lines covering the temperature range 10(4)-10(6) K, measured from high-spectral-resolution data for several solar features observed at the limb by the high resolution telescope and spectrograph (HRTS), including a coronal hole, 'quiescent regions' and several small-scale active regions. These results are compared with predictions based on acoustic waves and heating via Alfven waves. It is likely that more than one mechanism is operating simultaneously, in particular, resonant Alfven wave heating, which is very sensitive to background plasma motions. C1 USN,RES LAB,EO HULBURT CTR SPACE RES,WASHINGTON,DC 20375. QUEENS UNIV BELFAST,DEPT PURE & APPL PHYS,BELFAST BT7 1NN,ANTRIM,NORTH IRELAND. RP Doyle, JG (reprint author), ARMAGH OBSERV,ARMAGH BT61 9DG,NORTH IRELAND. NR 32 TC 30 Z9 30 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PD JUL PY 1997 VL 173 IS 2 BP 243 EP 258 DI 10.1023/A:1004981825463 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XQ472 UT WOS:A1997XQ47200004 ER PT J AU BarriosChoplin, B McCraty, R Cryer, B AF BarriosChoplin, B McCraty, R Cryer, B TI An inner quality approach to reducing stress and improving physical and emotional wellbeing at work SO STRESS MEDICINE LA English DT Article DE stress; hypertension; heart rate variability; autonomic nervous system; stress management; communication skills; job satisfaction ID HEART-RATE-VARIABILITY; OCCUPATIONAL STRESS; HEALTH; HYPERTENSION; HARDINESS; PRESSURE; DISEASE; MOOD AB This exploratory field study examined the impact of an Inner Quality Management program (IQM) on a group of Motorola employees. IQM is a training program designed to help people increase productivity through improved health, communication, goal clarity, positive mood and job satisfaction, and through the reduction of tension, burnout, physical symptoms of stress and negative mood. Both psychological and physiological measures were assessed in the 6-month study. The study involved three groups: managers, engineers and factory workers. Results showed that contentment, job satisfaction and communication significantly increased after the training, while tension, anxiety, nervousness and physical symptoms of stress significantly decreased. Blood pressure in hypertensive individuals decreased, and there was a reduction in sympathetic nervous activity. Implications for workplace wellbeing are discussed. (C) 1997 by John Wiley & Sons, Ltd. C1 INST HEARTMATH,BOULDER CREEK,CA 95006. USN,POSTGRAD SCH,DEPT SYST MANAGEMENT,MONTEREY,CA. NR 45 TC 10 Z9 10 U1 3 U2 16 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 0748-8386 J9 STRESS MEDICINE JI Stress Med. PD JUL PY 1997 VL 13 IS 3 BP 193 EP 201 DI 10.1002/(SICI)1099-1700(199707)13:3<193::AID-SMI744>3.0.CO;2-I PG 9 WC Psychiatry; Psychology SC Psychiatry; Psychology GA XL987 UT WOS:A1997XL98700009 ER PT J AU Tran, P AF Tran, P TI Calculation of the scattering of electromagnetic waves from a two-dimensional perfectly conducting surface using the method of ordered multiple interaction SO WAVES IN RANDOM MEDIA LA English DT Article ID ROUGH SURFACES; RANDOMLY ROUGH AB Calculations, using the method of ordered multiple interaction (MOMI), of the scattering of electromagnetic waves from a two-dimensional, randomly rough, perfectly conducting surface with a ratio of RMS height sigma to correlation length a of 1.0 or smaller are presented which demonstrate the robustness of the method. Convergence is achieved in six iterations or less. Some surfaces with sigma = a = 1.0 lambda and certain topological features exhibited slow convergence. The MOMI inherently will show slow convergence when there are multiple back and forth scatterings. Since resonant scattering is characterized by this type of scattering, this suggests the presence of surface resonances on these surfaces. RP Tran, P (reprint author), USN,AIR WARFARE CTR,WEAP DIV,RES & TECHNOL GRP,CODE 4B4000D,CHINA LAKE,CA 93555, USA. NR 7 TC 19 Z9 19 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL, ENGLAND BS1 6BE SN 0959-7174 J9 WAVE RANDOM MEDIA JI Waves Random Media PD JUL PY 1997 VL 7 IS 3 BP 295 EP 302 DI 10.1088/0959-7174/7/3/004 PG 8 WC Physics, Multidisciplinary SC Physics GA XM147 UT WOS:A1997XM14700003 ER PT J AU Elson, JM AF Elson, JM TI Characteristics of far-field scattering by means of surface roughness and variations in subsurface permittivity SO WAVES IN RANDOM MEDIA LA English DT Article ID OPTICAL MULTILAYERS; LIGHT-SCATTERING; BULK SCATTERING AB Using a first-order vector perturbation theory, we calculate some scattering characteristics of surfaces which have both surface roughness and subsurface permittivity variations. These variations are treated as random variables where the roughness yields phase perturbations and the permittivity variations yield reflectance perturbations. Numerical results are given for both types of scattering. RP Elson, JM (reprint author), USN,AIR WARFARE CTR,WEAP DIV,RES & TECHNOL GRP,COMPUTAT SCI BRANCH,CHINA LAKE,CA 93555, USA. NR 7 TC 23 Z9 23 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL, ENGLAND BS1 6BE SN 0959-7174 J9 WAVE RANDOM MEDIA JI Waves Random Media PD JUL PY 1997 VL 7 IS 3 BP 303 EP 317 DI 10.1088/0959-7174/7/3/005 PG 15 WC Physics, Multidisciplinary SC Physics GA XM147 UT WOS:A1997XM14700004 ER PT J AU Kirwan, AD Mied, RP Lipphardt, BL AF Kirwan, AD Mied, RP Lipphardt, BL TI Rotating modons over isolated topography in a two-layer ocean SO ZEITSCHRIFT FUR ANGEWANDTE MATHEMATIK UND PHYSIK LA English DT Article DE modon; baroclinic eddies; nonlinear vortices; multipoles; geophysical fluid dynamics ID WARM-CORE RING; COASTAL TRANSITION ZONE; LABORATORY EXPERIMENTS; CALIFORNIA CURRENT; VORTEX STRUCTURES; STRATIFIED FLUID; WESTERN GULF; SHOCK-WAVES; EDDIES; VORTICES AB The nonlinear quasigeostrophic equations for two layers with finite scale topography in the lower layer are reduced to steady form by focusing on solutions that rotate at a constant rate and also decay monotonically outside the topography. The solutions, here called rotating baroclinic modons, are a composition of one radially dependent azimuthal component and a basic axisymmetric component. Smoothness conditions (global continuity of the streamfunction and its first derivatives), when applied to the azimuthal mode, result in a complicated eigenvalue problem. The consequence of this is a single azimuthal mode with arbitrary amplitude. When applied to the axisymmetric solution component, the smoothness conditions allow for a. vortex of arbitrary amplitude, a rider, in each layer. These riders determine the rotation rats, which may be cyclonic or anticyclonic, as well as other modon parameters. Two special cases of the theory are discussed and numerical examples of the general solutions are given. The solutions exhibit a rich variety of behavior with a countable infinity of exact solution muitipoles. The paper concludes with a comparison of the properties of rotating and rectilinear baroclinic modons and some speculations on applications of the theory. C1 USN,RES LAB,DIV REMOTE SENSING,WASHINGTON,DC 20375. RP Kirwan, AD (reprint author), OLD DOMINION UNIV,CTR COASTAL PHYS OCEANOG,NORFOLK,VA 23529, USA. NR 55 TC 4 Z9 4 U1 0 U2 1 PU BIRKHAUSER VERLAG AG PI BASEL PA PO BOX 133 KLOSTERBERG 23, CH-4010 BASEL, SWITZERLAND SN 0044-2275 J9 Z ANGEW MATH PHYS JI Z. Angew. Math. Phys. PD JUL PY 1997 VL 48 IS 4 BP 535 EP 570 PG 36 WC Mathematics, Applied SC Mathematics GA XT027 UT WOS:A1997XT02700001 ER PT J AU Chu, TK Stumborg, MF Santiago, F AF Chu, TK Stumborg, MF Santiago, F TI Heteroepitaxial deposition of Group IIa fluorides on gallium arsenide SO MATERIALS SCIENCE AND ENGINEERING B-SOLID STATE MATERIALS FOR ADVANCED TECHNOLOGY LA English DT Article DE heteroepitaxial deposition; fluoride films; gallium arsenide ID BARIUM FLUORIDE; GROWTH; SI(111); INSULATOR; EPITAXY; GAAS; CAF2; BAF2 AB The epitaxial deposition of fluoride films has been a subject of research interest because of their potential for integrated electronic and electro-optic device applications. We report here our recent results on the investigation of(100) BaF2-GaAs growth. Our approach differs from the conventional method by addressing the problem at the atomic layer level, especially at the interface between the deposited material and the substrate. These investigations have revealed that an interfacial chemical reaction is important in the heteroepitaxy process. As a result of this chemical reaction, an atomic Ba layer is formed on the GaAs surface. It is this Ba-template layer that enables two dimensional, molecular layer-by-layer growth of the BaF2 film. Films thus grown are of a high epitaxial quality which appears to be limited only by the quality of the GaAs surface. For BaF2 on GaAs, (100) growth is favored over (III) growth. This is contrary to earlier results by other investigators. It is concluded that the conventional approach to heteroepitaxial growth, relying on lattice match and surface energies is not applicable, at least for the fluoride films. This can be understood from the atomic and molecular structure of Ba and BaF2. Implications of these results to the understanding of the heteroepitaxial process, especially involving large lattice mismatches, and to the development of new materials and technologies will be discussed. (C) 1997 Elsevier Science S.A. RP Chu, TK (reprint author), USN,CTR SURFACE WARFARE,DAHLGREN DIV,DAHLGREN,VA 22248, USA. NR 29 TC 3 Z9 3 U1 1 U2 1 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5107 J9 MAT SCI ENG B-SOLID JI Mater. Sci. Eng. B-Solid State Mater. Adv. Technol. PD JUN 30 PY 1997 VL 47 IS 3 BP 224 EP 234 DI 10.1016/S0921-5107(97)00036-6 PG 11 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA XQ319 UT WOS:A1997XQ31900006 ER PT J AU Ranganathan, D Kurur, S Madhusudanan, KP Karle, IL AF Ranganathan, D Kurur, S Madhusudanan, KP Karle, IL TI Self-assembling urea-based peptidomimetics: A simple one-step synthesis and crystal structure of core beta-alanyl ureylene retro-bispeptides (MeO-A(aa)-[NH-CO-NH]-CH2-CH2-CO-NH-A(aa)-OMe; A(aa)=amino acid A) SO TETRAHEDRON LETTERS LA English DT Article ID DESIGN; INHIBITORS AB A novel family of urea-based peptidomimetics containing beta-alanyl unit at the core has been synthesized by a simple one-step procedure. Solid state structures of some representative examples have showm self-assembly into highly ordered extended hydrogen-bonded chains and ribbons with modest NLO activity. (C) 1997 Elsevier Science Ltd. C1 CENT DRUG RES INST,LUCKNOW 226001,UTTAR PRADESH,INDIA. USN,RES LAB,STRUCT MATTER LAB,WASHINGTON,DC 20375. RP Ranganathan, D (reprint author), CSIR,REG RES LAB,BIOMOL RES UNIT,TRIVANDRUM 695019,KERALA,INDIA. RI TVM, NIIST/E-5132-2012 OI TVM, NIIST/0000-0002-5814-466X NR 21 TC 16 Z9 16 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0040-4039 J9 TETRAHEDRON LETT JI Tetrahedron Lett. PD JUN 30 PY 1997 VL 38 IS 26 BP 4659 EP 4662 DI 10.1016/S0040-4039(97)00960-X PG 4 WC Chemistry, Organic SC Chemistry GA XG713 UT WOS:A1997XG71300037 ER PT J AU Baronavski, AP Owrutsky, JC Pasternack, L AF Baronavski, AP Owrutsky, JC Pasternack, L TI Fluorescence quenching of NCO in CH4/O-2 and CH4/air premixed low pressure flames SO CHEMICAL PHYSICS LETTERS LA English DT Article ID SPECTROSCOPY; NO; A2-DELTA; KINETICS; O-2; CH AB The fluorescence quenching rate constant for the (A) over tilde state of NCO has been determined for NO doped CH4/O-2 and CH4/air premixed flames by directly measuring the fluorescence decay times over the pressure range 10-100 Torr. The rate constant k(Q)(P) for the NCO (A) over tilde(2) Sigma(+) (000) state in a stoichiometric CH4/O-2 flame with NO is 1.03 +/- 0.07 mu s(-1)Torr(-1). The rate constant measured for a similar CH4/air flame (0.54 +/- 0.05 mu s(-1)Torr(-1)) is smaller by a factor of 2. The ratio of NCO quenching rate constants for CH4/O-2 compared to CH4/air flames is similar to those for other species such as NO. A somewhat larger rate constant (1.31 +/- 0.08 mu s(-1)Torr(-1)) is measured for vibrationally excited levels of the (A) over tilde state of NCO, possibly due to vibrational energy transfer in the excited state. (C) 1997 Published by Elsevier Science B.V. RP Baronavski, AP (reprint author), USN,RES LAB,DIV CHEM,CODE 6111,WASHINGTON,DC 20375, USA. RI Owrutsky, Jeffrey/K-7649-2012 NR 23 TC 5 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD JUN 27 PY 1997 VL 272 IS 3-4 BP 239 EP 244 DI 10.1016/S0009-2614(97)88015-3 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA XH440 UT WOS:A1997XH44000016 ER PT J AU Fett, RW Englebretson, RE Burk, SD AF Fett, RW Englebretson, RE Burk, SD TI Techniques for analyzing lead condition in visible, infrared and microwave satellite imagery SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID AVHRR DATA; CLOUD DETECTION; COVER; CLASSIFICATION; ALBEDO; SNOW AB The condition of a lead or polynya, whether open, partially refrozen, or completely ice covered, is extremely important from many points of view. From a meteorological and climatological perspective the moisture and heat flux resulting from air and sea interaction over leads during cold weather periods is crucial. Enormous cloud plumes have been observed emanating from relatively small openings in leads and polynyas. Modeling studies have shown that plume development is extremely sensitive to changes in humidity, air temperature, and the nature of near-surface atmospheric lapse rates. The studies indicate that plumes can exist, even in the refreezing process, until the new ice becomes sufficiently thick so that its temperature approaches the temperature of the surrounding ice. Heat balance studies for modeling the arctic environment depend upon knowledge of such distinctions for accurate assessment of the radiation balance over the area at any given time. This paper describes a new visible channel differencing technique shown to have some capabilities in distinguishing between open and refrozen leads and, in larger leads, distinguishing the part that is open from that which is partially or newly refrozen. Output from this technique is correlated with infrared data in two examples over the Beaufort Sea and in a polynya example with additional microwave data over the Laptev Sea. Although in situ evidence for direct documentation of lead condition is limited, the existence of cloud plumes emanating from open leads provides some verification and establishment of remote sensing parameters indicative df an open or closed condition. A logical consistency of values from independent sensors over varying conditions of open water, mixed ice and water, new ice, and first or multiyear ice also provides contributing remote sensing evidence of lead condition. C1 USN, RES LAB, MARINE METEOROL DIV, MONTEREY, CA 93943 USA. RP Fett, RW (reprint author), SCI APPLICAT INT CORP, MONTEREY, CA 93940 USA. NR 31 TC 4 Z9 4 U1 1 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUN 27 PY 1997 VL 102 IS D12 BP 13657 EP 13671 DI 10.1029/97JD00340 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA XH196 UT WOS:A1997XH19600024 ER PT J AU Rasmussen, EA Guest, PS Davidson, KL AF Rasmussen, EA Guest, PS Davidson, KL TI Synoptic and mesoscale atmospheric features over the ice-covered portion of the Fram Strait in spring SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article; Proceedings Paper CT XXIst General Assembly of the International-Union-of-Geodesy-and-Geophysics CY JUL 02-14, 1995 CL BOULDER, CO SP Int Union Geodesy & Geophys ID ROSS SEA; ANTARCTICA; CYCLOGENESIS AB Data obtained during the Coordinated Eastern Arctic Experiment (CEAREX) from March 31 to April 20, 1989, from two ice camps in the pack ice region in the Fram Strait have been analyzed. The data show that the total period can be divided into two periods or regimes divided by a transition period. The first period was a radiative type, characterized by very low surface temperatures and low wind speeds. Fairly regular oscillations between southerly and northerly winds were caused by small-scale disturbances in the surface pressure field, associated with upper level waves of large amplitude. During a transition period toward an ''advective weather type'' on April 11 a sharp frontal zone passed both ice camps. The front was associated with a small-scale low which had formed over the ice on the shallow but intense baroclinic zone along the northeastern Greenland coast. Mesoscale vortices of this type may, if numerous enough, affect the horizontal transfer of heat from lower latitudes toward Arctic regions as well as the ice drift through the Fram Strait. C1 UNIV COPENHAGEN, DEPT GEOPHYS, DK-2100 COPENHAGEN, DENMARK. RP Rasmussen, EA (reprint author), USN, POSTGRAD SCH, DEPT METEOROL, MONTEREY, CA 93943 USA. NR 26 TC 7 Z9 7 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUN 27 PY 1997 VL 102 IS D12 BP 13975 EP 13986 DI 10.1029/96JD03361 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA XH196 UT WOS:A1997XH19600048 ER PT J AU Campbell, ML AF Campbell, ML TI Kinetics of the termolecular insertion reaction of ground state rhodium with methane SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID TRANSITION-METAL ATOMS; ALKANE C-H; GAS-PHASE REACTIONS; OXIDATIVE ADDITION; LINEAR ALKANES; ALKENES; HYDROCARBONS; ACTIVATION; PALLADIUM; COMPLEXES RP Campbell, ML (reprint author), USN ACAD,DEPT CHEM,ANNAPOLIS,MD 21402, USA. NR 21 TC 18 Z9 18 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD JUN 25 PY 1997 VL 119 IS 25 BP 5984 EP 5985 DI 10.1021/ja9708169 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA XG882 UT WOS:A1997XG88200037 ER PT J AU Saks, NS AF Saks, NS TI Measurement of single interface trap capture cross sections with charge pumping SO APPLIED PHYSICS LETTERS LA English DT Article AB A technique has been developed using charge pumping to determine electron and hole capture cross sections of individual interface traps in small silicon metal-oxide-semiconductor transistors. Values for both cross sections are approximate to 10(-16) cm(2) for the particular trap measured. (C) 1997 American Institute of Physics. RP Saks, NS (reprint author), USN,RES LAB,CODE 6813,WASHINGTON,DC 20375, USA. NR 9 TC 17 Z9 17 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JUN 23 PY 1997 VL 70 IS 25 BP 3380 EP 3382 DI 10.1063/1.119177 PG 3 WC Physics, Applied SC Physics GA XH231 UT WOS:A1997XH23100018 ER PT J AU Waldron, A AF Waldron, A TI Cultural realism: Strategic culture and grand strategy in Chinese history - Johnston,AI SO NEW REPUBLIC LA English DT Book Review C1 HARVARD UNIV,FAIRBANK CTR E ASIAN RES,CAMBRIDGE,MA 02138. RP Waldron, A (reprint author), USN,WAR COLL,WASHINGTON,DC 20350, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU NEW REPUBLIC INC PI WASHINGTON PA 1220 19TH ST NW SUITE 600, WASHINGTON, DC 20036 SN 0028-6583 J9 NEW REPUBLIC JI New Repub. PD JUN 23 PY 1997 VL 216 IS 25 BP 36 EP 41 PG 6 WC Political Science SC Government & Law GA XD397 UT WOS:A1997XD39700020 ER PT J AU Koon, NC AF Koon, NC TI Calculations of exchange bias in thin films with ferromagnetic/antiferromagnetic interfaces SO PHYSICAL REVIEW LETTERS LA English DT Article ID GROWN NI80FE20/FE50MN50 BILAYERS; MODEL AB A microscopic explanation of exchange bias in thin films with compensated ferro/antiferromagnetic interfaces is presented. Full micromagnetic calculations show the interfacial exchange coupling to be relatively strong with a perpendicular orientation between the ferro/antiferromagnetic axis directions, similar to the classic ''spin-flop'' state in bulk antiferromagnets. With reasonable parameters the calculations predict bias fields comparable to those observed and provide a possible explanation for both anomalous high field rotational hysteresis and recently discovered ''positive'' exchange bias. RP Koon, NC (reprint author), USN, RES LAB, WASHINGTON, DC 20375 USA. NR 13 TC 635 Z9 655 U1 18 U2 94 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JUN 23 PY 1997 VL 78 IS 25 BP 4865 EP 4868 DI 10.1103/PhysRevLett.78.4865 PG 4 WC Physics, Multidisciplinary SC Physics GA XJ269 UT WOS:A1997XJ26900049 ER PT J AU Kendziora, C Onellion, M AF Kendziora, C Onellion, M TI Superconducting gap anisotropy vs doping level in high-T-c cuprates - Reply SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTRONIC RAMAN-SCATTERING C1 UNIV WISCONSIN,DEPT PHYS,MADISON,WI 53706. RP Kendziora, C (reprint author), USN,RES LAB,CODE 6653,WASHINGTON,DC 20375, USA. NR 10 TC 4 Z9 4 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JUN 23 PY 1997 VL 78 IS 25 BP 4892 EP 4892 DI 10.1103/PhysRevLett.78.4892 PG 1 WC Physics, Multidisciplinary SC Physics GA XJ269 UT WOS:A1997XJ26900058 ER PT J AU Collins, GE Choi, LS AF Collins, GE Choi, LS TI Fluorescent diaza crown ether sensitive to complexation, conformation and microenvironment SO CHEMICAL COMMUNICATIONS LA English DT Article ID SOLVENT POLARITY AB A newly synthesized diaza crown ether, BPDC, demonstrates sensitivity to solvent polarity, microviscosity and metal complexation with spectroscopic changes in monomer and excimer fluorescence. RP Collins, GE (reprint author), USN,RES LAB,DIV CHEM,CODE 6116,WASHINGTON,DC 20375, USA. NR 9 TC 23 Z9 23 U1 0 U2 0 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON ROAD, CAMBRIDGE, CAMBS, ENGLAND CB4 4WF SN 1359-7345 J9 CHEM COMMUN JI Chem. Commun. PD JUN 21 PY 1997 IS 12 BP 1135 EP 1136 DI 10.1039/a701240c PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA XF674 UT WOS:A1997XF67400029 ER PT J AU Campbell, ML Hooper, KL AF Campbell, ML Hooper, KL TI Temperature-dependent study of the kinetics of Ta(a F-4(3/2)) with O-2, N2O, CO2 and NO SO JOURNAL OF THE CHEMICAL SOCIETY-FARADAY TRANSACTIONS LA English DT Article ID TRANSITION-METAL ATOMS; EXOTHERMIC HOMOLOGOUS REACTIONS; GAS-PHASE REACTIONS; LOW-LYING STATES; ACTIVATION BARRIERS; OXIDATION REACTIONS; ROOM-TEMPERATURE; LINEAR ALKANES; REACTIVITY; ALKENES AB The gas-phase reactivity of Ta(a(4)F(3/2)) with O-2, N2O, CO2 and NO in the temperature range 296-548 K is reported. The room-temperature removal rate constants for the spin-orbit excited states (a F-4(J), J = 5/2, 7/2, 9/2) are reported for these oxidants and CH4. Tantalum atoms were produced by the photodissociation of tetracarbonyl cyclopentadienyl tantalum(0) [Ta(C5H5)(CO)(4)] and detected by laser-induced fluorescence. The reaction rate constants of the a F-4(3/2) ground state with O-2, N2O, CO2 and NO are temperature dependent. The disappearance rates in the presence of all the reactants are independent of total pressure, indicating a bimolecular abstraction mechanism. The bimolecular rate constants are described in Arrhenius form by k(O-2) = (1.7 +/- 0.2) x 10(-10) exp(-7.8 +/- 0.4 kJ mol(-1)/RT) cm(3) s(-1), k(N2O) = (7.1 +/- 1.0) x 10(-11) exp(-13.6 +/- 0.6 kJ mol(-1)/RT) cm(3) s(-1) k(CO2) = (1.0 +/- 0.1) x 10(-10) exp(-26.8 +/- 0.5 kJ mol(-1)/RT) cm(3) s(-1) and k(NO)=(1.0 +/- 0.2) x 10(-10) exp(-1.6 +/- 0.8 kJ mol(-1)/RT) cm(3) s(-1) where the uncertainties are +/- 2 sigma. The removal rates of the spin-orbit excited states with O-2, N2O, CO2 and NO are spin-orbit state dependent and are generally faster than for the ground state. The F-4(3/2) ground state is unreactive with methane, although the spin-orbit excited states are quenched by methane. The a F-4(5/2), a F-4(7/2) and a F-4(9/2) states have second-order room-temperature removal rate constants in methane of 6.0 x 10(-13), 9.5 x 10(-13) and 2.3 x 10(-11) cm(3) s(-1) respectively. RP Campbell, ML (reprint author), USN ACAD,DEPT CHEM,ANNAPOLIS,MD 21402, USA. NR 48 TC 20 Z9 20 U1 0 U2 1 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON ROAD, CAMBRIDGE, CAMBS, ENGLAND CB4 4WF SN 0956-5000 J9 J CHEM SOC FARADAY T JI J. Chem. Soc.-Faraday Trans. PD JUN 21 PY 1997 VL 93 IS 12 BP 2139 EP 2146 DI 10.1039/a700915a PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA XH004 UT WOS:A1997XH00400002 ER PT J AU Sica, L AF Sica, L TI Asymptotic behavior of the boundary value problem of four-wave mixing in photorefractive media SO APPLIED OPTICS LA English DT Article AB Solutions to the four-wave mixing problem asymptotically approach a spatial steady state over large interaction distances. In this limit, intensities of the two-point boundary value problem may be found from solutions to quadratic equations. The different limiting behavior exhibited for positive and negative gain has important implications for applications in which linearity of system response is important. In the regime studied, positive gain leads quickly to maximally depleted pumps with increasing input signal. For negative gain, such depletion does not occur until higher signal levels are reached. RP Sica, L (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD JUN 20 PY 1997 VL 36 IS 18 BP 4142 EP 4148 DI 10.1364/AO.36.004142 PG 7 WC Optics SC Optics GA XE301 UT WOS:A1997XE30100018 PM 18253440 ER PT J AU Decaux, V Beiersdorfer, P Kahn, SM Jacobs, VL AF Decaux, V Beiersdorfer, P Kahn, SM Jacobs, VL TI High resolution measurement of the K alpha spectrum of Fe xxv-xviii: New spectral diagnostics of nonequilibrium astrophysical plasmas SO ASTROPHYSICAL JOURNAL LA English DT Article DE atomic data; atomic processes; methods, laboratory; plasmas ID SUPER-NOVA REMNANTS; BEAM ION-TRAP; LABORATORY PLASMAS; CROSS-SECTIONS; IRON; TEMPERATURE AB We present laboratory measurements of high-resolution spectra of iron I(a emission under transient ionization conditions similar to those that are believed to exist in stellar flares and young supernova remnants. Taking advantage of our high spectral resolution (lambda/Delta lambda greater than or equal to 2000, we identify a number of transitions that can serve as diagnostics of ionizing plasmas. By varying the excitation energy in the experiments, we constrain the effects of the electron distribution on these diagnostic lines. Using our measured line ratios, we deduce values for the ionization time, eta= N(e)t, in the plasma, which agree with the actual values to similar to 20% accuracy. This result gives us confidence to our ability to derive similar constraints on astrophysical plasmas from remote X-ray spectroscopic observations. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94551. UNIV CALIF BERKELEY,DEPT PHYS & ASTRON,BERKELEY,CA 94720. UNIV CALIF BERKELEY,SPACE SCI LAB,BERKELEY,CA 94720. USN,RES LAB,COMPLEX SYST THEORY BRANCH,DIV CONDENSED MATTER & RADIAT SCI,WASHINGTON,DC 20375. NR 25 TC 52 Z9 53 U1 0 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUN 20 PY 1997 VL 482 IS 2 BP 1076 EP 1084 DI 10.1086/304169 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XF541 UT WOS:A1997XF54100044 ER PT J AU Patrick, HJ Askins, CG McElhanon, RW Friebele, EJ AF Patrick, HJ Askins, CG McElhanon, RW Friebele, EJ TI Amplitude mask patterned on an excimer laser mirror for high intensity writing of long period fibre gratings SO ELECTRONICS LETTERS LA English DT Article DE gratings in fibres; masks ID FIBER AB Masks have been produced for long period fibre grating fabrication from commercial dielectric laser mirrors. The masks, which were produced by direct patterning of a photoresist using an argon laser, can withstand in excess of 200mJ/cm(2) per 15ns pulse of 248nm laser light. The use of these masks decreased exposure times by 90% and nearly doubled the attenuation (dB) of a long period grating produced by a given UV fluence compared to chrome-on-silica masks. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. RP Patrick, HJ (reprint author), USN, Res Lab, Div Opt Sci, Code 5600,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 8 TC 21 Z9 23 U1 0 U2 4 PU IEE-INST ELEC ENG PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 0013-5194 J9 ELECTRON LETT JI Electron. Lett. PD JUN 19 PY 1997 VL 33 IS 13 BP 1167 EP 1168 DI 10.1049/el:19970780 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA YX447 UT WOS:000072040900045 ER PT J AU Yang, MJ Yang, CH Bennett, BR Shanabrook, BV AF Yang, MJ Yang, CH Bennett, BR Shanabrook, BV TI Evidence of a hybridization gap in ''semimetallic'' InAs/GaSb systems SO PHYSICAL REVIEW LETTERS LA English DT Article ID BAND-STRUCTURE; QUANTUM WELLS; GASB; TRANSITION; STATES AB InAs/GaSb composite quantum wells sandwiched by AlSb are studied by using capacitance-voltage, quantum Hall, and three-terminal transfer measurements. Our data reveal a positive energy gap resulting from the hybridization of in-plane dispersions of electrons in InAs and holes in GaSb for conventionally recognized ''semimetallic'' InAs/GaSb heterostructures. C1 UNIV MARYLAND,COLLEGE PK,MD 20742. RP Yang, MJ (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. RI Bennett, Brian/A-8850-2008 OI Bennett, Brian/0000-0002-2437-4213 NR 18 TC 102 Z9 103 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JUN 16 PY 1997 VL 78 IS 24 BP 4613 EP 4616 DI 10.1103/PhysRevLett.78.4613 PG 4 WC Physics, Multidisciplinary SC Physics GA XE571 UT WOS:A1997XE57100021 ER PT J AU Kilpatrick, SJ Jaccodine, RJ Thompson, PE AF Kilpatrick, SJ Jaccodine, RJ Thompson, PE TI A diffusional model for the oxidation behavior of Si1-xGex alloys SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID FLUORINE-ENHANCED OXIDATION; HIGH-PRESSURE OXIDATION; GESI STRAINED LAYERS; WET OXIDATION; THERMAL-OXIDATION; SILICON; SIGE; KINETICS; GEXSI1-X/SI; GERMANIUM AB We have developed a kinetic model to describe the oxidation behavior of Si1-xGex alloys during Ge segregation, which compares the Deal-Grove flux of oxidant diffusing through the oxide to the maximum flux of Si diffusing through the Ge-rich layer. This is motivated by thermal oxidation experiments on Si1-xGex alloys (x<0.17) using a fluorine-containing ambient (O-2 and 200 ppm of NF3). The fluorine is known to modify point defect generation during oxidation of pure Si toward vacancy production, which is also the case for Ge in Si. We demonstrate that fluorinated oxidation of Si1-xGex enhances the oxidation rate by 25%-40% in the temperature range of 700-800 degrees C. Oxides formed at these temperatures were SiO2, while those formed at 600 degrees C exhibited a transition from SiO2 to mixed oxide growth at some point during the very early phase of oxidation, depending on the alloy composition. Consideration of these data suggests that other factors in addition to oxidation temperature must be considered in predicting which oxide type will be produced, in contrast to most previous reports. Our model, indeed, shows that alloy composition, oxide thickness, and oxidant partial pressure are also important parameters. We believe that the model is very useful in predicting the oxide type that should result from a given set of growth conditions, and in particular, it suggests that a changeover from SiO2 to mixed oxide formation is likely at some point during the oxidation process, particularly if carried to larger thicknesses. (C) 1997 American Institute of Physics. C1 LEHIGH UNIV,DEPT MAT SCI & ENGN,BETHLEHEM,PA 18015. USN,RES LAB,WASHINGTON,DC 20375. NR 49 TC 53 Z9 53 U1 1 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 15 PY 1997 VL 81 IS 12 BP 8018 EP 8028 DI 10.1063/1.365406 PG 11 WC Physics, Applied SC Physics GA XF588 UT WOS:A1997XF58800046 ER PT J AU Deng, F Ring, K Guan, ZF Lau, SS Dubbelday, WB Wang, N Fung, KK AF Deng, F Ring, K Guan, ZF Lau, SS Dubbelday, WB Wang, N Fung, KK TI Structural investigation of self-aligned silicidation on separation by implantation oxygen SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID EPITAXIAL COSI2 FILMS; TECHNOLOGY; RESISTANCE; MOSFETS; METALS; SI AB Self-aligned silicidation is a well-known process to reduce the source, drain, and gate parasitic resistances of submicron metal-oxide-semiconductor devices. This process is particularly useful for devices built on very thin Si layer (similar to 1000 Angstrom or less) on insulators. Since the amount of Si available for silicidation is limited by the thickness of the Si layer, once the Si in the source and drain region is fully consumed during silicidation, excessive silicide formation could lead to void formation near the silicide/silicon interface beneath the oxide edge. In this article, we study the effects of different metals (Ti, Ni, Co, and Co/Ti bilayer) with varying thickness on the formation of voids. A change in the moving species during lateral silicide formation was found to be the likely cause for the voids, even if the metals are the moving species during silicidation in the thin film case. (C) 1997 American Institute of Physics. C1 HONG KONG UNIV SCI & TECHNOL,DEPT PHYS,HONG KONG,HONG KONG. USN,COMMAND CONTROL & OCEAN SURVEILLANCE CTR,RDT&E DIV,NRAD,SAN DIEGO,CA 92152. RP Deng, F (reprint author), UNIV CALIF SAN DIEGO,DEPT ELECT & COMP ENGN,LA JOLLA,CA 92093, USA. RI Wang, Ning/B-5436-2011 NR 25 TC 12 Z9 12 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 15 PY 1997 VL 81 IS 12 BP 8040 EP 8046 DI 10.1063/1.365409 PG 7 WC Physics, Applied SC Physics GA XF588 UT WOS:A1997XF58800049 ER PT J AU Deng, F Johnson, RA Asbeck, PM Lau, SS Dubbelday, WB Hsiao, T Woo, J AF Deng, F Johnson, RA Asbeck, PM Lau, SS Dubbelday, WB Hsiao, T Woo, J TI Salicidation process using NiSi and its device application SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID TISI2; SILICIDES; CMOS; RESISTIVITY; TECHNOLOGY; STABILITY; METALS; COSI2; PHASE; SI AB Self-aligned silicidation is a well-known process to reduce source, drain, and gate resistances of submicron metal-oxide-semiconductor devices. This process is particularly useful for devices built on very thin Si layers (similar to 1000 Angstrom or less) on insulators because of the large source and drain resistances associated with the thin Si layer. NiSi is a good candidate for salicidation process due to its low resistivity, low formation temperature, little silicon consumption, and large stable processing temperature window. In this article, the formation of nickel mono-silicide (NiSi) using rapid thermal annealing, the thermal stability of NiSi on n(+) poly-Si and the contact resistance of NiSi on n(+) Si layers in a SIMOX structure were investigated. NiSi salicidation process was, then, incorporated into a NMOS/SLMOX device fabrication for partial and full consumption of the Si in the source and drain regions during the salicidation process. The effects of void formation and silicide encroachment on the device performance were also studied. (C) 1997 American Institute of Physics. C1 UNIV CALIF LOS ANGELES,DEPT ELECT ENGN,LOS ANGELES,CA 90024. USN,COMMAND CONTROL & OCEAN SURVEILLANCE CTR,RDT&E DIV,NRAD,SAN DIEGO,CA 92152. RP Deng, F (reprint author), UNIV CALIF SAN DIEGO,DEPT ELECT & COMP ENGN,LA JOLLA,CA 92093, USA. NR 21 TC 117 Z9 120 U1 1 U2 27 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 15 PY 1997 VL 81 IS 12 BP 8047 EP 8051 DI 10.1063/1.365410 PG 5 WC Physics, Applied SC Physics GA XF588 UT WOS:A1997XF58800050 ER PT J AU Kwiatek, SE Desai, V Moran, PJ Natishan, PM AF Kwiatek, SE Desai, V Moran, PJ Natishan, PM TI Characterization of cathodically deposited carbonaceous films on a silicon substrate SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID DIAMOND; SPECTROSCOPY AB Carbon-based deposits were electrochemically formed on silicon substrates in ethanol at room temperature. This work was based on the work reported by Namba, who described the electrochemical deposition of diamond from organic solutions. The deposits were analysed using a scanning electron microscope, energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and electrochemical impedance spectroscopy. Scanning electron micrographs showed some crystalline deposits on the silicon. EDS was unable to identify carbon in the film, but did reveal impurities such as sodium, potassium, calcium and zinc. It was later established that the impurities most likely came from impurities in the graphite used for a counter electrode. XPS showed the presence of carbon species, and subsequently Raman spectroscopy was used to classify further the carbon deposits. Raman spectroscopy showed the presence of amorphous carbon in some films, but no diamond peak was observed for any of the films. EIS revealed that the impedance of the deposited films was nearly identical to that of the uncoated silicon, and did not resemble the impedance of diamond. Thus, in this work, carbon-based films were formed electrochemically, but these films were not diamond. C1 USN,RES LAB,WASHINGTON,DC 20375. UNIV CENT FLORIDA,DEPT MECH & AEROSP ENGN,ORLANDO,FL 32816. RP Kwiatek, SE (reprint author), USN ACAD,DEPT MECH ENGN,ANNAPOLIS,MD 21402, USA. NR 13 TC 26 Z9 30 U1 2 U2 8 PU CHAPMAN HALL LTD PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8HN SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD JUN 15 PY 1997 VL 32 IS 12 BP 3123 EP 3128 DI 10.1023/A:1018638314997 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA XG480 UT WOS:A1997XG48000005 ER PT J AU Kang, JU Ding, YJ Burns, WK Melinger, JS AF Kang, JU Ding, YJ Burns, WK Melinger, JS TI Backward second-harmonic generation in periodically poled bulk LiNbO3 SO OPTICS LETTERS LA English DT Article ID BLUE-LIGHT GENERATION AB We experimentally demonstrate backward second-harmonic generation in periodically poled LiNbO3 with a 3.3-mu m domain period. We observed high-order phase matching near 1490, 1600, and 1700 nm (fundamental) for the 19th, 16th, and 17th orders, respectively, with a maximum conversion efficiency of 0.02%. (C) 1997 Optical Society of America. C1 BOWLING GREEN STATE UNIV,DEPT PHYS & ASTRON,BOWLING GREEN,OH 43403. RP Kang, JU (reprint author), USN,RES LAB,CODE 5672,WASHINGTON,DC 20375, USA. RI Kang, Jin/A-3228-2010 NR 9 TC 55 Z9 56 U1 0 U2 6 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD JUN 15 PY 1997 VL 22 IS 12 BP 862 EP 864 DI 10.1364/OL.22.000862 PG 3 WC Optics SC Optics GA XE107 UT WOS:A1997XE10700006 PM 18185687 ER PT J AU Arend, MF Dennis, ML Duling, IN Golovchenko, EA Pilipetskii, AN Menyuk, CR AF Arend, MF Dennis, ML Duling, IN Golovchenko, EA Pilipetskii, AN Menyuk, CR TI Nonlinear-optical loop mirror demultiplexer using a random birefringence fiber: Comparisons between simulations and experiments SO OPTICS LETTERS LA English DT Article ID SOLITONS; DISPERSION; STABILITY AB A numerical simulation of the switching characteristics of a polarization multiplexed nonlinear-optical loop mirror demultiplexer is presented and compared with experiment. The model assumes that the optical fiber that composes the loop has a randomly varying birefringence, that the signal and the control pulses have the same frequency, and that these pulses are nearly solitons. Factors that affect the shape and the width of the switching window curve are discussed. A phase-dependent modulation of the switching window curve, which is due to incomplete averaging of the light polarization state, is observed both experimentally and numerically. Models in which the randomness is neglected are not able to describe this modulation adequately. (C) 1997 Optical Society of America. C1 UNIV MARYLAND BALTIMORE CTY,DEPT COMP SCI & ELECT ENGN,BALTIMORE,MD 21228. RP Arend, MF (reprint author), USN,RES LAB,CODE 5671,WASHINGTON,DC 20375, USA. NR 14 TC 7 Z9 7 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD JUN 15 PY 1997 VL 22 IS 12 BP 886 EP 888 DI 10.1364/OL.22.000886 PG 3 WC Optics SC Optics GA XE107 UT WOS:A1997XE10700014 PM 18185695 ER PT J AU Mansour, AN Dmitrienko, A Soldatov, AV AF Mansour, AN Dmitrienko, A Soldatov, AV TI Electronic structure of Ni3Al and NiAl3 alloys: X-ray-absorption fine-structure analysis SO PHYSICAL REVIEW B LA English DT Article ID MULTIPLE-SCATTERING ANALYSIS; PD ALLOYS; TRANSITION-METALS; SPECTRA; NI; SPECTROSCOPY; AMPLITUDE; STATES AB X-ray-absorption fine structure (XAFS) above the Ni K edge in Ni3Al and NiAl3 alloys has been measured and theoretical full multiple-scattering analysis of these data have been done. The theoretical XAFS are found to be in agreement with experimental data. The XAFS of Ni3Al and NiAl3 alloys are rather different. Since the dipole transition matrix element is nota very sharp function of the energy the experimental XAFS reflects the averaged in space partial Ni p unoccupied states in the conduction bands of the Ni3Al and NiAl3 alloys, showing changes in the electronic structure going from Ni3Al to NiAl3 alloy. Theoretical partial density of states curves calculated along the axis parallel to the c vector differ from the partial density of states curves calculated in the ab plane for both alloys. C1 ROSTOV DON STATE UNIV,DEPT SOLID STATE PHYS,ROSTOV NA DONU 344090,RUSSIA. RP Mansour, AN (reprint author), USN,CTR SURFACE WARFARE,CARDEROCK DIV,CODE 684,9500 MACARTHUR BLVD,BETHESDA,MD 20817, USA. OI Soldatov, Alexander/0000-0001-8411-0546 NR 23 TC 17 Z9 17 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD JUN 15 PY 1997 VL 55 IS 23 BP 15531 EP 15536 DI 10.1103/PhysRevB.55.15531 PG 6 WC Physics, Condensed Matter SC Physics GA XH335 UT WOS:A1997XH33500043 ER PT J AU Corcoran, SG Colton, RJ Lilleodden, ET Gerberich, WW AF Corcoran, SG Colton, RJ Lilleodden, ET Gerberich, WW TI Anomalous plastic deformation at surfaces: Nanoindentation of gold single crystals SO PHYSICAL REVIEW B LA English DT Article ID LOAD AB Nanoindentation data on single-crystal Au(111), Au(110), and Au(100) are presented and show an interesting yielding phenomenon-this yielding behavior is composed of a series of discrete yielding events separated by elastic deformation. The onset of this behavior is in agreement with calculations for the theoretical shear strength of gold. Good quantitative agreement is found between the experimental results and a model developed for the nucleation and multiplication of dislocations by a simple Frank-Read source under the indenter tip. C1 USN,RES LAB,WASHINGTON,DC 20375. UNIV MINNESOTA,DEPT CHEM ENGN & MAT SCI,MINNEAPOLIS,MN 55455. NR 17 TC 228 Z9 228 U1 2 U2 32 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD JUN 15 PY 1997 VL 55 IS 24 BP 16057 EP 16060 PG 4 WC Physics, Condensed Matter SC Physics GA XJ271 UT WOS:A1997XJ27100021 ER PT J AU Hinarejos, JJ Castro, GR Segovia, P Alvarez, J Michel, EG Miranda, R RodriguezMarco, A SanchezPortal, D Artacho, E Yndurain, F Yang, SH Ordejon, P Adams, JB AF Hinarejos, JJ Castro, GR Segovia, P Alvarez, J Michel, EG Miranda, R RodriguezMarco, A SanchezPortal, D Artacho, E Yndurain, F Yang, SH Ordejon, P Adams, JB TI Surface electronic structure of metastable FeSi(CsCl)(111) epitaxially grown on Si(111) SO PHYSICAL REVIEW B LA English DT Article ID PHOTOELECTRON SPECTROSCOPIES; IRON SILICIDES; REAL-SPACE; SEMICONDUCTORS; SYSTEMS; FILMS AB We report an investigation on the electronic structure of metastable, epitaxial FeSi films grown on Si(111). The electronic structure of the metastable silicides was probed with angle-resolved photoemission, and com-pared with theoretical calculations. We identify the silicide as FeSi crystallizing in the CsCl structure. Its surface is Fe terminated, and presents a prominent, strongly dispersing surface state at a binding energy of -3.5 eV in <(Gamma)over bar>. Its origin lies in the truncation of Fe bonds at the surface, and thus it has a major Fe d(z)2 content. C1 UNIV AUTONOMA MADRID,INST NICOLAS CABRERA,E-28049 MADRID,SPAIN. USN,RES LAB,WASHINGTON,DC 20375. UNIV OVIEDO,DEPT FIS,E-33007 OVIEDO,SPAIN. ARIZONA STATE UNIV,CHEM BIO & MAT DEPT,TEMPE,AZ 85287. RP Hinarejos, JJ (reprint author), UNIV AUTONOMA MADRID,DEPT FIS MAT CONDENSADA,CANTOBLANCO,E-28049 MADRID,SPAIN. RI Sanchez-Portal, Daniel /E-5858-2010; Ordejon, Pablo/D-3091-2014; yndurain, felix/J-2794-2014; Michel, Enrique/A-1545-2008; Artacho, Emilio/G-2616-2015; Castro, German/H-6679-2015 OI Ordejon, Pablo/0000-0002-2353-2793; Michel, Enrique/0000-0003-4207-7658; Artacho, Emilio/0000-0001-9357-1547; Castro, German/0000-0003-4251-3245 NR 30 TC 13 Z9 13 U1 2 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD JUN 15 PY 1997 VL 55 IS 24 BP 16065 EP 16068 PG 4 WC Physics, Condensed Matter SC Physics GA XJ271 UT WOS:A1997XJ27100023 ER PT J AU Li, Y Langreth, DC Pederson, MR AF Li, Y Langreth, DC Pederson, MR TI Surface structure of MgO (001): Ab initio versus shell model SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE; MGO(001) SURFACE; OXIDE SURFACES; MGO(100) SURFACE; MAGNESIUM-OXIDE; ALKALI-HALIDES; RELAXATION; LEED; ENERGETICS; ADSORPTION AB We have performed first-principles calculations on quasicubic MgO clusters for sizes up to 64 atoms. The results of these calculations have been used to determine a generalized environmentally dependent shell model (EDSM). In addition to reproducing the results from the first-principles calculations we suggest that the resulting EDSM parameters are more physical and more transferable than previous parametrizations based on bulk properties. First, we show that the force-constant matrix derived from the EDSM leads to an efficient approach to preconditioning. A full geometrical optimization of the quasicubic 64-atom MgO cluster is accomplished with a total of four first-principles force evaluations which is significantly less than what is required from a conjugate-gradient algorithm. Second, we use the shell-model parameters to study the relaxation and rumpling of an infinite (001) surface. The agreement between the EDSM and recent medium-energy scattering results is excellent and is significantly better than the agreement between conventional shell-model results and experiment. We show that these improvements are due to a more accurate accounting of the appropriate atomic polarizabilities: not only are these insensitively determined by previous methods, but also those for surface atoms are quite different from their counterparts for bulk atoms. C1 USN,RES LAB,COMPLEX SYST THEORY BRANCH,WASHINGTON,DC 20375. RP Li, Y (reprint author), RUTGERS STATE UNIV,DEPT PHYS & ASTRON,POB 849,PISCATAWAY,NJ 08855, USA. NR 44 TC 22 Z9 22 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD JUN 15 PY 1997 VL 55 IS 24 BP 16456 EP 16465 DI 10.1103/PhysRevB.55.16456 PG 10 WC Physics, Condensed Matter SC Physics GA XJ271 UT WOS:A1997XJ27100068 ER PT J AU Hoffman, SL Bancroft, WH Gottlieb, M James, SL Burroughs, ECB Stephenson, JR Morgan, MJ AF Hoffman, SL Bancroft, WH Gottlieb, M James, SL Burroughs, ECB Stephenson, JR Morgan, MJ TI Funding for malaria genome sequencing SO NATURE LA English DT Letter C1 USA,MED RES & MAT COMMAND,MIL INFECT DIS RES PROGRAM,FREDERICK,MD 21703. NIAID,NIH,PARASITOL & INT PROGRAMS BRANCH,BETHESDA,MD 20892. WELLCOME FUND,MORRISVILLE,NC 27560. WELLCOME TRUST RES LABS,LONDON NW1 2BE,ENGLAND. RP Hoffman, SL (reprint author), USN,MED RES INST,MALARIA PROGRAM,BETHESDA,MD 20889, USA. NR 0 TC 28 Z9 28 U1 0 U2 1 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD JUN 12 PY 1997 VL 387 IS 6634 BP 647 EP 647 DI 10.1038/42571 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA XD869 UT WOS:A1997XD86900018 PM 9192878 ER PT J AU Johnson, WN McNaronBrown, K Kurfess, JD Zdziarski, AA Magdziarz, P Gehrels, N AF Johnson, WN McNaronBrown, K Kurfess, JD Zdziarski, AA Magdziarz, P Gehrels, N TI Long-term monitoring of NGC 4151 by OSSE SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies, individual (NGC 4151); galaxies, Seyfert; gamma rays, observations ID ACTIVE GALACTIC NUCLEI; PAIR PRODUCTION; SPECTRAL FEATURES; COMPACT SOURCES; RAY-SPECTRUM; NGC-4151; VARIABILITY AB We report results of over 5 yr monitoring of the Seyfert galaxy NGC 4151 by the Oriented Scintillation Spectrometer Experiment (OSSE) on the Compton Gamma Ray Observatory. A total of more than 139 days of observations in the energy band 50 keV-10 MeV was obtained in 11 viewing periods. These observations show a photon spectrum in the 50-800 keV band that is well described by an exponentially cutoff power law of the form Phi(E) proportional to E(-1.6)e(-E/100 keV). Long-term luminosity changes of no more than a factor of 2 are observed with only modest change in the spectral shape. With these data we set the most sensitive limit to date on positron annihilation radiation from a Seyfert active galactic nucleus and address the role of e(+/-) pair production and nonthermal processes in this source. C1 NICHOLAS COPERNICUS ASTRON CTR,PL-00716 WARSAW,POLAND. JAGIELLONIAN UNIV,ASTRON OBSERV,KRAKOW,POLAND. NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. RP Johnson, WN (reprint author), USN,RES LAB,EO HULBURT CTR SPACE RES,CODE 7650,WASHINGTON,DC 20375, USA. RI Gehrels, Neil/D-2971-2012; Johnson, Neil/G-3309-2014 NR 28 TC 31 Z9 31 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUN 10 PY 1997 VL 482 IS 1 BP 173 EP 177 DI 10.1086/304148 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XD370 UT WOS:A1997XD37000019 ER PT J AU Luhman, ML Jaffe, DT Sternberg, A Herrmann, F Poglitsch, A AF Luhman, ML Jaffe, DT Sternberg, A Herrmann, F Poglitsch, A TI Near-infrared H-2 and associated O-0 and C+ emission from dense photon-dominated regions SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared, ISM, lines and bands; ISM, clouds; ISM, individual, Orion; ISM, molecules; molecular processes ID MOLECULAR-HYDROGEN EMISSION; FINE-STRUCTURE EXCITATION; PHOTODISSOCIATION REGIONS; ULTRAVIOLET-RADIATION; PHYSICAL CONDITIONS; INTERSTELLAR H2; FLUORESCENT H-2; LINE EMISSION; ORION NEBULA; CLOUDS AB We have observed near-infrared H-2 vibrational line emission from dense (n greater than or similar to 10(4) cm(-3)) photon-dominated regions (PDRs) along the Orion A molecular cloud ''ridge'' and toward the Orion B molecular cloud near NGC 2024. Specifically, we have observed the 1.601 pm v = 6-4 Q(1), 2.121 mu m v = 1-0 S(1), and 2.247 mu m v = 2-1 S(1) lines of H-2. To assess the physical state of the PDRs, we combine our H-2 data with observations of the [O I] 63 mu m, [O I] 146 mu m, and [C II] 158 mu m atomic fine-structure lines along the same lines of sight. We use our data to study how the character of the H-2 emission depends on the PDR conditions. For the range of densities (10(4)-10(5) cm(-3)) and incident far-ultraviolet fluxes (10(3)-10(5) times the mean interstellar field) in the PDRs, we find that the relative H-2 line strengths are characteristic of both low gas density and high gas density UV-excited emission. In Orion, we observe direct evidence of the transition from the (low-density) regime in which the H-2 vibrational cascade is dominated by radiative transitions to the (high-density) regime in which collisions influence the vibrational cascade. Our observations show that, for Orion-type abundances and physical conditions,collisions begin to influence the H-2 ro-vibrational line ratios near a gas density of 5 x 10(4) cm(-3). C1 UNIV TEXAS,DEPT ASTRON,AUSTIN,TX 78712. TEL AVIV UNIV,SCH PHYS & ASTRON,IL-69978 TEL AVIV,ISRAEL. MAX PLANCK INST EXTRATERR PHYS,D-85740 GARCHING,GERMANY. RP Luhman, ML (reprint author), USN,RES LAB,DIV REMOTE SENSING,CODE 7217,WASHINGTON,DC 20375, USA. NR 66 TC 20 Z9 20 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUN 10 PY 1997 VL 482 IS 1 BP 298 EP 306 DI 10.1086/304128 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XD370 UT WOS:A1997XD37000028 ER PT J AU Doschek, GA Warren, HP Laming, JM Mariska, JT Wilhelm, K Lemaire, P Schuhle, U Moran, TG AF Doschek, GA Warren, HP Laming, JM Mariska, JT Wilhelm, K Lemaire, P Schuhle, U Moran, TG TI Electron densities in the solar polar coronal holes from density-sensitive line ratios of Si VIII and S X SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun, corona; ultraviolet, stars AB We derive electron densities as a function of height in the north and south polar coronal holes from a forbidden spectral line ratio of Si VIII. Si vm is produced at about 8 x 10(5) K in ionization equilibrium. We also derive densities from a similar line ratio of S x (1.3 x 10(6) K). The spectra were obtained with the Solar Ultraviolet Measurements of Emitted Radiation spectrometer flown on the Solar and Heliospheric Observatory spacecraft. In addition to the primary mechanism of electron impact excitation, the derivation of theoretical level populations for Si VIII and S x includes both proton and resonance capture excitation. We compare the coronal hole results to quiet-Sun coronal measurements obtained outside the east and west limbs. We find for distances of a few arcseconds outside the solar limb that the average line-of-sight electron densities in the coronal holes are about a factor of 2 lower than in quiet-Sun regions. The decrease of density with height is exponential in the polar holes. We also confirm the result known from a variety of earlier observations that the temperature of most of the plasma in coronal holes does not exceed about 10(6) K. C1 SACHS FREEMAN ASSOCIATES INC,LANDOVER,MD 20785. MAX PLANCK INST AERON,D-37189 KATLENBURG DUHM,GERMANY. UNIV PARIS 11,UNITE MIXTE CNRS,INST ASTROPHYS SPATIALE,F-91405 ORSAY,FRANCE. APPL RES CORP,NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. RP Doschek, GA (reprint author), USN,RES LAB,EO HULBURT CTR SPACE RES,WASHINGTON,DC 20375, USA. NR 20 TC 78 Z9 78 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUN 10 PY 1997 VL 482 IS 1 BP L109 EP L112 DI 10.1086/310668 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XD371 UT WOS:A1997XD37100028 ER PT J AU Montes, MJ VanDyk, SD Weiler, KW Sramek, RA Panagia, N AF Montes, MJ VanDyk, SD Weiler, KW Sramek, RA Panagia, N TI Radio detection of SN 1986E in NGC 4302 SO ASTROPHYSICAL JOURNAL LA English DT Article DE supernovae, individual (SN 1986E) ID EMISSION AB Radio observations of SN 1986E show a clear detection of emission at 6 cm wavelength about 8 months after optical discovery. Combined with a number of new upper limits and a study of the possible models, these observations suggest that SN 1986B was probably a fairly normal Type IIL supernova, somewhat similar to SN 1980K, with radio emission at roughly the expected levels. This detection agrees with the general correlation between radio detection and late-time optical emission. C1 UNIV CALIF LOS ANGELES,DEPT PHYS & ASTRON,LOS ANGELES,CA 90095. NATL RADIO ASTRON OBSERV,SOCORRO,NM 87801. SPACE TELESCOPE SCI INST,BALTIMORE,MD 21218. ESA,DIV ASTROPHYS,DEPT SPACE SCI,F-75738 PARIS 15,FRANCE. RP Montes, MJ (reprint author), USN,RES LAB,REMOTE SENSING DIV,CODE 7214,WASHINGTON,DC 20375, USA. RI Montes, Marcos/J-9239-2015; OI Montes, Marcos/0000-0002-4725-5380; Van Dyk, Schuyler/0000-0001-9038-9950 NR 13 TC 12 Z9 12 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUN 10 PY 1997 VL 482 IS 1 BP L61 EP L64 DI 10.1086/310694 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XD371 UT WOS:A1997XD37100016 ER PT J AU Tebbens, SF Cande, SC Kovacs, L Parra, JC LaBrecque, JL Vergara, H AF Tebbens, SF Cande, SC Kovacs, L Parra, JC LaBrecque, JL Vergara, H TI The Chile ridge: A tectonic framework SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID OCEANIC FRACTURE-ZONES; EAST PACIFIC RISE; SOUTH-PACIFIC; MAGNETIC-ANOMALIES; THERMAL-STRESSES; TRIPLE JUNCTION; DRIVING FORCES; PLATE; EVOLUTION; MICROPLATE AB A new Chile ridge tectonic framework is developed based on satellite altimetry data, shipboard geophysical data and, primarily, 38,500 km of magnetic data gathered on a joint U.S.-Chilean aeromagnetic survey. Eighteen active transforms with fossil fracture zones (FZs), including two complex systems (the Chile FZ and Valdivia FZ systems), have been mapped between the northern end of the Antarctic-Nazca plate boundary (Chile ridge) at 35 degrees S and the Chile margin triple junction at 47 degrees S. Chile ridge spreading rates from 23 Ma to Present have been determined and show slowdowns in spreading rates that correspond to times of ridge-trench collisions. The Valdivia FZ system, previously mapped as two FZs with an uncharted seismically active region between them, is now recognized to be a multiple-offset FZ system composed of six FZs separated by short ridge segments 22 to 27 km long. At chron 5A (similar to 12 Ma), the Chile ridge propagated from the Valdivia FZ system northward into the Nazca plate through crust formed 5 Myr earlier at the Pacific-Nazca ridge. Evidence for this propagation event includes the Friday and Crusoe troughs, located at discontinuities in the magnetic anomaly sequence and interpreted as pseudofaults. This propagation event led to the formation of the Friday microplate, which resulted in the transferal of crust from the Nazca plate to the Antarctic plate, and in a 500-km northward stepwise migration of the Pacific-Antarctic-Nazca triple junction. Rift propagation, microplate formation, microplate extinction, and stepwise triple junction migration are found to occur during large-scale plate motion changes and plate boundary changes in the southeast Pacific. C1 UNIV CALIF SAN DIEGO, SCRIPPS INST OCEANOG, LA JOLLA, CA 92093 USA. USN, RES LAB, WASHINGTON, DC 20375 USA. COLUMBIA UNIV, LAMONT DOHERTY GEOL OBSERV, PALISADES, NY 10964 USA. GEODATOS, SANTIAGO, CHILE. SERV HIDROGRAF & OCEANOGRAF ARMADA CHILE, VALPARAISO, CHILE. RP Tebbens, SF (reprint author), UNIV S FLORIDA, DEPT MARINE SCI, 140 7TH AVE S, ST PETERSBURG, FL 33701 USA. NR 61 TC 87 Z9 89 U1 0 U2 10 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD JUN 10 PY 1997 VL 102 IS B6 BP 12035 EP 12059 DI 10.1029/96JB02581 PG 25 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA XD578 UT WOS:A1997XD57800025 ER PT J AU Compton, RN Tuinman, AA Klots, CE Pederson, MR Patton, DC AF Compton, RN Tuinman, AA Klots, CE Pederson, MR Patton, DC TI Electron attachment to a negative ion: e+C-84(-)reversible arrow C-84(-2) SO PHYSICAL REVIEW LETTERS LA English DT Article ID GROUND-STATE; ANIONS; SUPERCONDUCTIVITY; C-60; C60; C84 AB The observation of sequential attachment of two electrons to the C-84 molecule and the subsequent autodetachment of the C-84 dianion is reported. Remarkably, the cross section for attaching the second electron is estimated to be of the same order as that for adding the first electron. The measured lifetime for autodetachment of C-84(-2) (similar to 60 mu sec) is in accord with calculations assuming ''thermionic emission'' from the vibrationally hot dianion. The first (EA(1)) and second (EA(2)) electron affinities of the two low-lying D-2 and D-2d isomers of C-84 are calculated using density functional theory to be +3.14 and +0.44 eV, respectively. C1 UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996. OAK RIDGE NATL LAB,CHEM PHYS SECT,OAK RIDGE,TN 37831. USN,RES LAB,WASHINGTON,DC 20375. RP Compton, RN (reprint author), UNIV TENNESSEE,DEPT CHEM,KNOXVILLE,TN 37996, USA. NR 24 TC 97 Z9 97 U1 0 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JUN 9 PY 1997 VL 78 IS 23 BP 4367 EP 4370 DI 10.1103/PhysRevLett.78.4367 PG 4 WC Physics, Multidisciplinary SC Physics GA XD384 UT WOS:A1997XD38400015 ER PT J AU Kruppa, W Boos, JB Park, D Bennett, BR Bass, R AF Kruppa, W Boos, JB Park, D Bennett, BR Bass, R TI Microwave noise characteristics of AlSb/InAs HEMTs SO ELECTRONICS LETTERS LA English DT Article DE field effect transistors; Indium compounds; noise AB The microwave noise characteristics of AlSb/InAs HEMTs are reported for the first time. Although the noise performance is presently limited by the gate leakage current, a minimum noise figure of 1dB at 4GHz was measured. Simulations based on these measurements indicate that very low noise performance is achievable at drain voltages < 0.5V. C1 USN, Res Lab, Washington, DC 20375 USA. RP Kruppa, W (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Bennett, Brian/A-8850-2008 OI Bennett, Brian/0000-0002-2437-4213 NR 4 TC 10 Z9 10 U1 0 U2 0 PU IEE-INST ELEC ENG PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 0013-5194 J9 ELECTRON LETT JI Electron. Lett. PD JUN 5 PY 1997 VL 33 IS 12 BP 1092 EP 1093 DI 10.1049/el:19970691 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA YX446 UT WOS:000072040800065 ER PT J AU Cowan, DN DeFraites, RF Gray, GC Goldenbaum, MB Wishik, SM AF Cowan, DN DeFraites, RF Gray, GC Goldenbaum, MB Wishik, SM TI The risk of birth defects among children of Persian Gulf War veterans SO NEW ENGLAND JOURNAL OF MEDICINE LA English DT Article ID CONGENITAL-MALFORMATIONS AB Background There has been suspicion that service in the Persian Gulf War affected the health of veterans adversely, and there have been claims of an increased rate of birth defects among the children of those veterans. Methods We evaluated the routinely collected data on all live births at 135 military hospitals in 1991, 1992, and 1993. The data base included up to eight diagnoses from the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) for each birth hospitalization, plus information on the demographic characteristics and service history of the parents. The records of over 75,000 newborns were evaluated for any birth defect (ICD-9-CM codes 740 to 759, plus neoplasms and hereditary diseases) and for birth defects defined as severe on the basis of the specific diagnoses and the criteria of the Centers for Disease Control and Prevention. Results During the study period, 33,998 infants were born to Gulf War veterans and 41,463 to nondeployed veterans at military hospitals. The overall risk of any birth defect was 7.45 percent, and the risk of severe birth defects was 1.85 percent. These rates are similar to those reported in civilian populations. In the multivariate analysis, there was no significant association for either men or women between service in the Gulf War and the risk of any birth defect or of severe birth defects in their children. Conclusions This analysis found no evidence of an increase in the risk of birth defects among the children of Gulf War veterans. (C) 1997, Massachusetts Medical Society. C1 WALTER REED ARMY MED CTR,WALTER REED ARMY INST RES,WASHINGTON,DC 20307. USN,HLTH RES CTR,SAN DIEGO,CA 92152. US DEPT DEF,DEPLOYMENT SURVEILLANCE TEAM,WASHINGTON,DC. UNIV CALIF SAN DIEGO,LA JOLLA,CA 92093. RP Cowan, DN (reprint author), SRA TECHNOL INC,8110 GATEHOUSE RD,SUITE 600W,FALLS CHURCH,VA 22042, USA. NR 17 TC 86 Z9 88 U1 0 U2 0 PU MASS MEDICAL SOC PI BOSTON PA 10 SHATTUCK, BOSTON, MA 02115 SN 0028-4793 J9 NEW ENGL J MED JI N. Engl. J. Med. PD JUN 5 PY 1997 VL 336 IS 23 BP 1650 EP 1656 DI 10.1056/NEJM199706053362306 PG 7 WC Medicine, General & Internal SC General & Internal Medicine GA XC086 UT WOS:A1997XC08600006 PM 9171068 ER PT J AU Wang, FC Zhang, WE Yang, CH Yang, MJ Bennett, BR Wilson, RA Stone, DR AF Wang, FC Zhang, WE Yang, CH Yang, MJ Bennett, BR Wilson, RA Stone, DR TI A tunneling field-effect transistor with 25 nm metallurgical channel length SO APPLIED PHYSICS LETTERS LA English DT Article AB A tunneling field-effect transistor with an ultrashort channel-length of 25 nm has been experimentally realized using InAs/AlSb heterostructures. The conduction between the source and the drain is through a sequential process, including tunneling and drift-diffusion mechanisms. According to its operating principle, the transistor is inherently free of the conventional shea-channel effects. The results demonstrate a new scheme of building nanometer-scale transistors. (C) 1997 American Institute of Physics. C1 UNIV MARYLAND,DEPT ELECT ENGN,COLLEGE PK,MD 20742. USN,RES LAB,WASHINGTON,DC 20375. JOINT PROGRAM ADV ELECT MAT,PHYS SCI LAB,COLLEGE PK,MD 20742. RI Bennett, Brian/A-8850-2008 OI Bennett, Brian/0000-0002-2437-4213 NR 6 TC 7 Z9 7 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JUN 2 PY 1997 VL 70 IS 22 BP 3005 EP 3007 DI 10.1063/1.118731 PG 3 WC Physics, Applied SC Physics GA XB501 UT WOS:A1997XB50100026 ER PT J AU Agrawal, BN Elshafei, MA Song, GB AF Agrawal, BN Elshafei, MA Song, GB TI Adaptive antenna shape control using piezoelectric actuators SO ACTA ASTRONAUTICA LA English DT Article; Proceedings Paper CT 47th International Astronautical Congress CY OCT 07-11, 1996 CL BEIJING, PEOPLES R CHINA ID INTELLIGENT STRUCTURES; COMPOSITE PLATES; STATIC ANALYSIS AB This paper presents improved techniques for the shape control of composite material plates using piezoelectric actuators. The application of this work is for the shape control of spacecraft antenna to correct surface errors introduced by manufacturing, in-orbit thermal distortion, and moisture. A finite element model has been developed for a composite plate with distributed piezoelectric actuators and sensors. To improve the accuracy of the prediction of plate deformation, a simple higher-order deformation theory is used. The electric potential is treated as a generalized coordinate, allowing it to vary over the element. The applied voltages to the actuators are optimized to minimize the error between the desired shape and the deformed shape. Based on these techniques, two computer programs were developed on finite element modeling and optimization. The analytical results demonstrate the use of piezo-electric actuators for the active shape control of spacecraft antennas. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN, Postgrad Sch, Dept Aeronaut & Astronaut, Spacecraft Res & Design Ctr, Monterey, CA 93940 USA. RP Agrawal, BN (reprint author), USN, Postgrad Sch, Dept Aeronaut & Astronaut, Spacecraft Res & Design Ctr, 1 Univ Circle, Monterey, CA 93940 USA. NR 9 TC 25 Z9 28 U1 0 U2 8 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0094-5765 J9 ACTA ASTRONAUT JI Acta Astronaut. PD JUN PY 1997 VL 40 IS 11 BP 821 EP 826 DI 10.1016/S0094-5765(97)00185-9 PG 6 WC Engineering, Aerospace SC Engineering GA ZD430 UT WOS:000072684400008 ER PT J AU Martin, A Pinkerton, AA Gilardi, RD Bottaro, JC AF Martin, A Pinkerton, AA Gilardi, RD Bottaro, JC TI Energetic materials: The preparation and structural characterization of three biguanidinium dinitramides SO ACTA CRYSTALLOGRAPHICA SECTION B-STRUCTURAL SCIENCE LA English DT Article ID THERMAL-DECOMPOSITION; AMMONIUM DINITRAMIDE; SALTS; THERMOCHEMISTRY; CHEMISTRY AB Three biguanidinium salts of the energetic dinitramide anion have been prepared and structurally characterized from room-temperature X-ray diffraction data. Biguanidinium mono-dinitramide, (BIGH)(DN), triclinic, , a = 4.3686(4), b = 9.404(2), c = 10.742(1) Angstrom, alpha = 83.54(1), beta = 80.386(9), gamma = 79.93(1)degrees, V = 426.8 (1) Angstrom(3), Z = 2, D-x = 1.62 g cm(-3). Biguanidinium bis-dinitramide, (BIGH(2))(DN)(2), monoclinic, C2/c, a = 11.892(2), b = 8.131(1), c = 13.038(2) Angstrom, beta = 115.79(1)degrees, V = 1135.1(3) Angstrom(3), Z = 4, D-x = 1.84 g cm(-3). Biguanidinium bis-dinitramide monohydrate, (BIGH(2))(DN)(2) . H2O, orthorhombic, P2(1)2(1)2(1), a = 6.4201(6), b = 13.408(1), c = 14.584(2) Angstrom, V = 1255.4(4) Angstrom(3), Z = 4, D-x = 1.76 g cm(-3). All three structures are characterized by extensive hydrogen bonding. Both the mono- and diprotontated cations consist of two planar halves twisted with respect to each other. The dinitramide anion has a surprisingly variable and asymmetric structure. The two halves of the anion are twisted with respect to each other; however, the twist varies from 5.1 to 28.9 degrees. In addition, the two ends of the anion have significantly different geometries, e.g. the 'equivalent' N-N bond lengths differ by up to 0.045 Angstrom. C1 USN,RES LAB,WASHINGTON,DC 20375. SRI INT,MENLO PK,CA 94025. RP Martin, A (reprint author), UNIV TOLEDO,DEPT CHEM,TOLEDO,OH 43606, USA. OI pinkerton, alan/0000-0002-2239-1992 NR 37 TC 29 Z9 31 U1 0 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-7681 J9 ACTA CRYSTALLOGR B JI Acta Crystallogr. Sect. B-Struct. Commun. PD JUN 1 PY 1997 VL 53 BP 504 EP 512 DI 10.1107/S0108768196013183 PN 3 PG 9 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA XF740 UT WOS:A1997XF74000022 ER PT J AU Mahajan, S Pande, CS Imam, MA Rath, BB AF Mahajan, S Pande, CS Imam, MA Rath, BB TI Formation of annealing twins in f.c.c. crystals SO ACTA MATERIALIA LA English DT Article ID FCC METALS; ALLOYS AB A microscopic model for the formation of annealing twins in f.c.c. crystals is proposed. It is argued that Shockley partial loops nucleate on consecutive {111} planes by growth accidents occurring on migrating {111} steps associated with a moving grain boundary. The higher the velocity of the boundary, the higher the twin density. The absence of twins in high stacking fault energy materials and the influence of temperature on twin density can be rationalized in terms of the model. Additional supporting, circumstantial evidence has been developed by examining the influence of deformation damage on the incidence of twinning in copper and the effect of boron in reducing twin density in annealed nickel. (C) 1997 Acta Metallurgica Inc. C1 USN,RES LAB,WASHINGTON,DC 20375. RP Mahajan, S (reprint author), CARNEGIE MELLON UNIV,DEPT MAT SCI & ENGN,PITTSBURGH,PA 15213, USA. NR 16 TC 249 Z9 254 U1 14 U2 99 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD JUN PY 1997 VL 45 IS 6 BP 2633 EP 2638 DI 10.1016/S1359-6454(96)00336-9 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA XE069 UT WOS:A1997XE06900037 ER PT J AU Chesnakas, CJ Simpson, RL AF Chesnakas, CJ Simpson, RL TI Detailed investigation of the three-dimensional separation about a 6:1 prolate spheroid SO AIAA JOURNAL LA English DT Article ID FLOW AB The flow in the crossflow separation region of a 6:1 prolate spheroid at 10- and 20-deg angle of attack, Re-L = 4.20 x 10(6), was investigated using a novel, miniature, three dimensional, fiber-optic laser Doppler velocimeter (LDV). The probe was used to measure three simultaneous, orthogonal velocity components from within the model, and these measurements were simultaneous with wall-pressure measurements made just below the LDV probe volume. The LDV measurements extend from approximately y(+) = 7 out to beyond the boundary-layer edge. The design and operation of this LDV probe is summarized. Plots of velocity, skin friction, wall-flow angle, mean and fluctuating pressures, turbulent kinetic energy, helicity density, and secondary streamlines are used to show the location of separation and reattachment lines. These measurements are also used to show that a trough of fluid, which is quite distinct from the rest of the flow, exists just downstream of the separation sheet. This trough has fluid of very low mean and turbulent kinetic energy. Plots of the turbulence anisotropy show there to be little correlation between the flow-gradient and the turbulent-shear-stress angles over large regions of the flow. This implies that turbulence models employing the eddy viscosity concept cannot be adapted to three-dimensional separated flows such as this. C1 VIRGINIA POLYTECH INST & STATE UNIV,DEPT AEROSP & OCEAN ENGN,BLACKSBURG,VA 24061. RP Chesnakas, CJ (reprint author), USN,CTR SURFACE WARFARE,DAVID TAYLOR MODEL BASIN,CARDEROCK DIV,CODE 5400,9500 MACARTHUR BLVD,BETHESDA,MD 20817, USA. NR 20 TC 25 Z9 28 U1 0 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0001-1452 J9 AIAA J JI AIAA J. PD JUN PY 1997 VL 35 IS 6 BP 990 EP 999 DI 10.2514/2.208 PG 10 WC Engineering, Aerospace SC Engineering GA XC113 UT WOS:A1997XC11300008 ER PT J AU Fine, B Gaglione, AM Rosenberger, G Spellman, D AF Fine, B Gaglione, AM Rosenberger, G Spellman, D TI The commutative transitive kernel SO ALGEBRA COLLOQUIUM LA English DT Article DE commutative transitivity; commutative transitive kernel; T-like functor AB A group G is commutative transitive, provided the relation of commutativity is transitive on the nonidentity elements of G. A subgroup T(G) is constructed and the main theorem asserts that (1) T(G) is a characteristic subgroup of G contained in the commutator subgroup of G, (2) G/T(G) is commutative transitive, and (3) G is commutative transitive if and only if T(G) = 1. More generally, if N is a normal subgroup in G, then T(G, N) is constructed as the union of an increasing chain of normal subgroups N = T-0(G, N) subset of or equal to T-1(G, N) subset of or equal to ..., and T(G) is defined as T(G, 1). C1 USN ACAD,DEPT MATH,ANNAPOLIS,MD 21402. UNIV DORTMUND,FACH MATH,D-4600 DORTMUND 50,GERMANY. ST JOSEPHS UNIV,DEPT MATH & COMP SCI,PHILADELPHIA,PA 19131. RP Fine, B (reprint author), FAIRFIELD UNIV,DEPT MATH & COMP SCI,FAIRFIELD,CT 06430, USA. NR 11 TC 3 Z9 3 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 1005-3867 J9 ALGEBR COLLOQ JI Algebr. Colloq. PD JUN PY 1997 VL 4 IS 2 BP 141 EP 152 PG 12 WC Mathematics, Applied; Mathematics SC Mathematics GA XV251 UT WOS:A1997XV25100003 ER PT J AU Taylor, HA AF Taylor, HA TI Rural practice and obstetrics fellowships for family physicians SO AMERICAN FAMILY PHYSICIAN LA English DT Letter RP Taylor, HA (reprint author), NAVAL HOSP,JACKSONVILLE,FL 32214, USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER ACAD FAMILY PHYSICIANS PI KANSAS CITY PA 8880 WARD PARKWAY, KANSAS CITY, MO 64114-2797 SN 0002-838X J9 AM FAM PHYSICIAN JI Am. Fam. Physician PD JUN PY 1997 VL 55 IS 8 BP 2603 EP 2604 PG 2 WC Primary Health Care; Medicine, General & Internal SC General & Internal Medicine GA XE084 UT WOS:A1997XE08400005 PM 9191446 ER PT J AU Maffeo, R AF Maffeo, R TI Back to basics - Helping families cope with type I diabetes SO AMERICAN JOURNAL OF NURSING LA English DT Article RP Maffeo, R (reprint author), USN,NURSE CORPS,NAVAL SCH HLTH SCI,FT SAM HOUSTON,SAN ANTONIO,TX, USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT-RAVEN PUBL PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 SN 0002-936X J9 AM J NURS JI Am. J. Nurs. PD JUN PY 1997 VL 97 IS 6 BP 36 EP 39 PG 4 WC Nursing SC Nursing GA XC761 UT WOS:A1997XC76100023 PM 9197816 ER PT J AU Baird, JK Leksana, B Masbar, S Suradi Sutanihardja, MA Fryauff, DJ Subianto, B AF Baird, JK Leksana, B Masbar, S Suradi Sutanihardja, MA Fryauff, DJ Subianto, B TI Whole blood chloroquine concentrations with Plasmodium vivax infection in Irian Jaya, Indonesia SO AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE LA English DT Article ID RESISTANCE; PRIMAQUINE; FALCIPARUM AB Whole blood concentrations of self-administered chloroquine (CQ) and its metabolite desethylchloroquine (DCQ) were measured in 168 patients with microscopically confirmed infection by Plasmodium vivax in northeastern Irian Jaya, Indonesia. The study consisted of both survey and passive case detection in four separate villages between 1992 and 1994. The subjects were Javanese people 4-51 years old who had lived in the Arso region for up to two years. The sum of CQ and DCQ ranged from 0 to 8,342 ng/ml of whole blood, and 122 subjects (73%) had greater than or equal to 100 ng/ml of CQ plus DCQ, the estimated minimally effective concentration (MEG) in whole blood against chloroquine-sensitive P. vivax. Among 56 subjects reporting to a clinic with symptoms of malaria, 53 (95%) had ordinarily effective levels of chloroquine in blood. Among 109 largely asymptomatic malaria patients found by survey case detection, 69 (63%) had chloroquine blood levels greater than the MEG. Virtually all clinical and most subclinical vivax malaria in this region occurs despite ordinarily effective levels of chloroquine in blood. C1 USN,MED RES UNIT NO 2,JAKARTA,INDONESIA. PROV HLTH SERV,IRIAN JAYA,INDONESIA. RP Baird, JK (reprint author), USN,MED RES INST ANNEX,MALARIA PROGRAM,12300 WASHINGTON AVE,ROCKVILLE,MD 20852, USA. NR 7 TC 16 Z9 16 U1 0 U2 2 PU AMER SOC TROP MED & HYGIENE PI MCLEAN PA 8000 WESTPARK DRIVE SUITE 130, MCLEAN, VA 22101 SN 0002-9637 J9 AM J TROP MED HYG JI Am. J. Trop. Med. Hyg. PD JUN PY 1997 VL 56 IS 6 BP 618 EP 620 PG 3 WC Public, Environmental & Occupational Health; Tropical Medicine SC Public, Environmental & Occupational Health; Tropical Medicine GA XL429 UT WOS:A1997XL42900009 PM 9230791 ER PT J AU Baird, JK Leksana, B Masbar, S Fryauff, DJ Sutanihardja, MA Suradi Wignall, FS Hoffman, SL AF Baird, JK Leksana, B Masbar, S Fryauff, DJ Sutanihardja, MA Suradi Wignall, FS Hoffman, SL TI Diagnosis of resistance to chloroquine by Plasmodium vivax: Timing of recurrence and whole blood chloroquine levels SO AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE LA English DT Article ID PERFORMANCE LIQUID-CHROMATOGRAPHY; DESETHYL-CHLOROQUINE; IRIAN-JAYA; DESETHYLCHLOROQUINE; PLASMA; INDONESIA; PROPHYLAXIS; FALCIPARUM; SAMPLES; HEALTHY AB To develop criteria for the diagnosis of resistance to chloroquine using an in vivo test, we examined published records of early clinical trials of quinine and chloroquine against Plasmodium vivax. These data established the timing of relapse by tropical P. vivax relative to therapy by these drugs. The first relapse occurred 17 days after initiating and three days after terminating quinine therapy. The median day of relapse was day 23, and 59% of the patients had relapsed by day 30 (n = 333). In contrast, no relapse occurred until day 36 following chloroquine treatment (n = 256). Data from our laboratory may help explain this difference; among 91 Indonesian patients with malaria, the mean whole blood levels of chloroquine (CQ) and desethylchloroquine (DCQ) were 141 ng/ml (95% confidence interval = 115-167) on day 28 after initiating standard therapy (25 mg base/kg in three doses over a 48-hr period). This exceeds the estimated minimal effective concentration of chloroquine (100 ng/ml of whole blood). Thus, chloroquine lingering in the blood for at least 28 days after starting standard therapy was sufficient to eliminate or at least suppress chloroquine-sensitive tropical P. vivax. We conclude that a parasitemia by P. vivax recurring in the 28 days after full compliance to standard chloroquine therapy demonstrates resistance. If the recurrence appears before day 16, it is almost certainly a recrudescence and between days 17 and 28 it may be either a recrudescence or a relapse by chloroquine-resistant parasites. Recurrences beyond day 28 could be relapse by chloroquine-sensitive P. vivax. C1 USN,MED RES UNIT NO 2,JAKARTA,INDONESIA. RP Baird, JK (reprint author), USN,MED RES INST ANNEX,MALARIA PROGRAM,12300 WASHINGTON AVE,ROCKVILLE,MD 20852, USA. NR 34 TC 116 Z9 123 U1 0 U2 2 PU AMER SOC TROP MED & HYGIENE PI MCLEAN PA 8000 WESTPARK DRIVE SUITE 130, MCLEAN, VA 22101 SN 0002-9637 J9 AM J TROP MED HYG JI Am. J. Trop. Med. Hyg. PD JUN PY 1997 VL 56 IS 6 BP 621 EP 626 PG 6 WC Public, Environmental & Occupational Health; Tropical Medicine SC Public, Environmental & Occupational Health; Tropical Medicine GA XL429 UT WOS:A1997XL42900010 PM 9230792 ER PT J AU Baird, JK Wiady, I Fryauff, DJ Sutanihardja, MA Leksana, B Widjaya, H Kysdarmanto Subianto, B AF Baird, JK Wiady, I Fryauff, DJ Sutanihardja, MA Leksana, B Widjaya, H Kysdarmanto Subianto, B TI In vivo resistance to chloroquine by Plasmodium vivax and Plasmodium falciparum at Nabire, Irian Jaya, Indonesia SO AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE LA English DT Article ID PRIMAQUINE; MALARIA; PROPHYLAXIS AB A survey of resistance to chloroquine by Plasmodium vivax and P. falciparum was conducted during May 1995 at three mesoendemic villages 30 km southeast of Nabire, near the central northern coast of Irian Jaya, Indonesia. The prevalence of malaria at Urusumu (n = 157), Margajaya (n = 573), and Topo (n = 199) was 18%, 9%, and 9%, respectively, with spleen rates among children of 79%, 10%, and 27%. Infected patients among those screened formed a study population of 64 subjects eligible for a 28-day in vivo test of resistance to chloroquine. Sixty-three patients successfully completed the test; 45 males and 18 females 1-60 years of age, of whom 29 were Javanese transmigrants of five years residence in Irian Jaya and 34 were native to Irian Jaya. The seven-day day cumulative incidence of therapeutic failure for P. vivax and P. falciparum was 15% (n = 34) and 30% (n = 37). The 14- and 28-day estimates of cumulative incidence were 45% and 64% for P. vivax and 58% and 89% for P. falciparum. Almost ail recurrences appeared in the face of ordinarily effective levels of chloroquine and its major metabolite, desethylchloroquine, in whole blood (greater than or equal to 100 ng/ml). Four infections by P. malariae in subjects enrolled in this study cleared by day 2 and none reappeared within 28 days. Chloroquine no longer provides effective therapy for falciparum or vivax malaria along the northern coast of Irian Jaya, Indonesia. C1 USN,MED RES UNIT NO 2,JAKARTA,INDONESIA. REG HLTH CLIN,IRIAN JAYA,INDONESIA. PROV HLTH SERV JAYAPURA,IRIAN JAYA,INDONESIA. RP Baird, JK (reprint author), USN,MED RES INST ANNEX,MALARIA PROGRAM,12300 WASHINGTON AVE,ROCKVILLE,MD 20852, USA. NR 25 TC 67 Z9 69 U1 0 U2 0 PU AMER SOC TROP MED & HYGIENE PI MCLEAN PA 8000 WESTPARK DRIVE SUITE 130, MCLEAN, VA 22101 SN 0002-9637 J9 AM J TROP MED HYG JI Am. J. Trop. Med. Hyg. PD JUN PY 1997 VL 56 IS 6 BP 627 EP 631 PG 5 WC Public, Environmental & Occupational Health; Tropical Medicine SC Public, Environmental & Occupational Health; Tropical Medicine GA XL429 UT WOS:A1997XL42900011 PM 9230793 ER PT J AU Andersen, E Jones, TR Purnomo Masbar, S Wiady, I Tirtolusumo, S Bangs, MJ Charoenvit, Y Gunawan, S Hoffman, SL AF Andersen, E Jones, TR Purnomo Masbar, S Wiady, I Tirtolusumo, S Bangs, MJ Charoenvit, Y Gunawan, S Hoffman, SL TI Assessment of age-dependent immunity to malaria in transmigrants SO AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE LA English DT Article ID PLASMODIUM-FALCIPARUM; ANTIBODIES; EXPOSURE; VACCINE AB Sixty-six Javanese transmigrants moving from Java, an area of very low malaria transmission, to Irian Jaya, an area of high malaria transmission, were monitored to evaluate the effects of exposure to malaria transmission and age on resistance to infection and the induction of humoral immunity. The risk of acquiring Plasmodium falciparum parasitemia was not statistically greater in children (5-15 years of age) than in adults (> 15 years of age) during the first 14 months of exposure. However, during the cross-sectional survey at 14 months of exposure, children did have significantly higher P. falciparum asexual blood-stage parasite densities. Serum antibody titers to R32LR, a peptide containing sequences from the P. falciparum circumsporozoite repeat region, and MSP19, a proteolytic fragment of merozoite surface protein-1 (MSP-1) from P. falciparum, were measured by enzyme-linked immunosorbent assay. Exposure for both six and 14 months produced statistically significant increased antibody titers to both R32LR and MSP-1; no age-dependent difference in antibody titers was observed. In this population, exposure to malaria transmission induced antibodies to antigens associated with immunity to malaria. In addition, we noted an age-dependent difference in the parasitemia density of P. falciparum. C1 USN,MED RES UNIT 2,JAKARTA,INDONESIA. USN,MED RES INST,MALARIA PROGRAM,ROCKVILLE,MD 20852. NIH,RES & DEV,JAKARTA,INDONESIA. NR 8 TC 6 Z9 7 U1 0 U2 2 PU AMER SOC TROP MED & HYGIENE PI MCLEAN PA 8000 WESTPARK DRIVE SUITE 130, MCLEAN, VA 22101 SN 0002-9637 J9 AM J TROP MED HYG JI Am. J. Trop. Med. Hyg. PD JUN PY 1997 VL 56 IS 6 BP 647 EP 649 PG 3 WC Public, Environmental & Occupational Health; Tropical Medicine SC Public, Environmental & Occupational Health; Tropical Medicine GA XL429 UT WOS:A1997XL42900015 PM 9230797 ER PT J AU Watts, DM Lavera, V Callahan, J Rossi, C Oberste, MS Roehrig, JT Cropp, CB Karabatsos, N Smith, JF Gubler, DJ Wooster, MT Nelson, WM Hayes, CG AF Watts, DM Lavera, V Callahan, J Rossi, C Oberste, MS Roehrig, JT Cropp, CB Karabatsos, N Smith, JF Gubler, DJ Wooster, MT Nelson, WM Hayes, CG TI Venezuelan equine encephalitis and Oropouche virus infections among Peruvian army troops in the Amazon region of Peru SO AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE LA English DT Article ID MONOCLONAL-ANTIBODIES; ENCEPHALOMYELITIS VIRUS; HEMORRHAGIC-FEVER; SOUTH-AMERICA; IDENTIFICATION; EPITOPES; VACCINE; TC-83; NEUTRALIZATION; TOGAVIRIDAE AB An outbreak of a febrile illness characterized by headache, ocular pain, myalgia, and arthralgia occurred during June 1994 among Peruvian army troops in Northern Peru. On June 14-16, 1994, clinical data and blood samples were obtained from eight soldiers with a febrile illness, and from 26 others who had a history of febrile illness during the past three months. A follow-up blood sample was obtained 107 days later from four of the febrile and seven of the afebrile soldiers. Serum samples were tested for dengue (DEN), Oropouche (ORO), and Venezuelan equine encephalitis (VEE) IgM and IgG antibodies by an enzyme-linked immunosorbent assay (ELISA). Virus isolation was performed by inoculation of newborn mice and Vero cell cultures. Viral isolates were identified by immunofluorescence, ELISA, and nucleotide sequencing. A VEE virus infection was confirmed in three of the eight febrile soldiers, two by virus isolation, and one by serology. Antigenic analysis indicated that one of the virus isolates was similar to VEE subtype I, variety LD, viruses previously isolated in Colombia and Venezuela. Nucleotide sequence data showed that both viral isolates were identical to one another and closely related to VEE ID viruses previously isolated in Peru, Colombia, and Venezuela. Serologic results showed that two of 26 afebrile soldiers had IgM antibody to VEE and four had Ige antibody to VEE; two febrile soldiers had IgG antibody in their first serum samples. Oropouche-specific IgM antibody was detected in one of the eight febrile and five of the afebrile soldiers, and 18 of the 34 soldiers had low titers of ORO IgG antibody titers, which did not meet the diagnostic criteria for confirmed cases. All soldiers were negative for DEN IgM antibody, and 10 had flavivirus IgG antibody that reacted with DEN antigens. These data indicated that VEE ID virus was one of the causes of illness among Peruvians soldiers and that this was the first association of this VEE subtype with human disease in Peru. C1 SANTA ROSA ARMY HOSP,IQUITOS,PERU. CTR DIS CONTROL & PREVENT,DIV VECTOR BORNE INFECT DIS,NATL CTR INFECT DIS,FT COLLINS,CO 80522. USA,MED RES INST INFECT DIS,FREDERICK,MD 21702. USN,MED RES INST,DEPT INFECT DIS,BETHESDA,MD 20889. RP Watts, DM (reprint author), USN,MED RES INST DETACHMENT,NAMRID,UNIT 3800,AMER EMBASSY,APO AA 34031,LIMA,PERU. OI Roehrig, John/0000-0001-7581-0479 NR 43 TC 37 Z9 38 U1 1 U2 2 PU AMER SOC TROP MED & HYGIENE PI MCLEAN PA 8000 WESTPARK DRIVE SUITE 130, MCLEAN, VA 22101 SN 0002-9637 J9 AM J TROP MED HYG JI Am. J. Trop. Med. Hyg. PD JUN PY 1997 VL 56 IS 6 BP 661 EP 667 PG 7 WC Public, Environmental & Occupational Health; Tropical Medicine SC Public, Environmental & Occupational Health; Tropical Medicine GA XL429 UT WOS:A1997XL42900018 PM 9230800 ER PT J AU DeCredico, M AF DeCredico, M TI Richmond during the war - Putnam,SB SO ARKANSAS HISTORICAL QUARTERLY LA English DT Book Review RP DeCredico, M (reprint author), USN ACAD,ANNAPOLIS,MD 21402, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ARKANSAS HISTORICAL ASSOC PI FAYETTEVILLE PA UNIV ARKANSAS, DEPT OF HISTORY, FAYETTEVILLE, AR 72701 SN 0004-1823 J9 ARKANSAS HIST QUART JI Ark. Hist. Q. PD SUM PY 1997 VL 56 IS 2 BP 240 EP 241 PG 2 WC History SC History GA XJ120 UT WOS:A1997XJ12000010 ER PT J AU Sanchez, AA Hennrikus, WL AF Sanchez, AA Hennrikus, WL TI Arthroscopically assisted treatment of acute septic knees in infants using the micro-joint arthroscope SO ARTHROSCOPY LA English DT Article; Proceedings Paper CT American-Orthopaedic-Association Residents Annual Meeting CY MAR, 1996 CL BALTIMORE, MD SP Amer Orthopaed Assoc DE septic arthritis; knee; infant; arthroscopy ID NEEDLE ASPIRATION; SURGICAL DRAINAGE; INFECTED JOINTS; ARTHRITIS; IMMUNIZATION; MANAGEMENT; DIAGNOSIS; CHILDREN; DISEASE AB Five infants with an acute hematogenous septic arthritis of the knee were treated with arthroscopically assisted drainage using the Micro-Joint Arthroscope (MJA; Linvatec, Large, FL) combined with antibiotic therapy and early postoperative motion. The average patient age was 16 months (range, 4 to 24 months). No surgical or anesthetic complications occurred. All knees were clinically and radiologically normal at an average follow-up of 26 months. C1 USN HOSP,DEPT ORTHOPAED SURG & CLIN INVEST,SAN DIEGO,CA 92134. NR 40 TC 5 Z9 7 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 SN 0749-8063 J9 ARTHROSCOPY JI Arthroscopy PD JUN PY 1997 VL 13 IS 3 BP 350 EP 354 DI 10.1016/S0749-8063(97)90033-5 PG 5 WC Orthopedics; Surgery SC Orthopedics; Surgery GA XE070 UT WOS:A1997XE07000012 PM 9195033 ER PT J AU Guetter, HH Turner, DG AF Guetter, HH Turner, DG TI IC 1590, a young cluster embedded in the nebulosity of NGC 281 SO ASTRONOMICAL JOURNAL LA English DT Article ID GALACTIC CLUSTERS; CEPHEID VARIABLES; REDDENING LINES; MASSIVE STARS; PHOTOMETRY; IC-1805; SYSTEMS AB Photoelectric and CCD photometry (tea limit of V = 17.0) is presented for 61 and 243 stars, respectively total of 279 individual stars-in and about IC 1590, a young galactic cluster embedded in the nebulosity of NGC 281, the H II region S184. New spectroscopic observations are also presented for 20 stars in or near the cluster. A small amount of differential reddening is observed across the face of IC 1590, and is described by a visual reddening relation of slope EU-B/EB-V = 0.735. From near infrared photometry of bright cluster members in the I and K bands and a variable-extinction analysis of ZAMS members, the value of R = A(V)/EB-V, the ratio of total to selective absorption, is found to be 3.44 +/- 0.07, slightly larger than what has been found for other nearby galactic fields. Most of the cluster reddening appears to originate in dust clouds which are similar to 0.66 kpc and 2.0-2.2 kpc distant, the latter cloud lying in the immediate foreground of the cluster, which has a derived distance of 2.94 +/- 0.15 kpc (V-0-M-V = 12.34 +/- 0.11 s.d., +/- 0.03 s.e.). IC 1590 is extremely young and has an estimated age for its 63 identified probable members of 3.5(+/- 0.2) x 10(6) years, with very little evidence for age spread. Its well-defined sequence of 22 gravitationally-contracting stars, the choice of which is supported by star counts and reddening information, provides evidence for the extreme youth of the cluster's central trapezium system, HD 5005. According to the luminosity distribution of likely cluster members, the initial mass function for IC 1590 has a slope of Gamma = -1.00 +/- 0.21, similar to what has been found for other very young clusters and associations. Given that the photometric study terminates at a magnitude limit marginally brighter than where embedded protostars and T Tauri variables belonging to the cluster are expected to be found, IC 1590 would make an excellent target for Hubble Space Telescope observations. (C) 1997 American Astronomical Society. C1 ST MARYS UNIV,DEPT PHYS & ASTRON,HALIFAX,NS B3H 3C3,CANADA. RP Guetter, HH (reprint author), USN OBSERV,FLAGSTAFF STN,POB 1149,FLAGSTAFF,AZ 86002, USA. NR 58 TC 33 Z9 33 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0004-6256 J9 ASTRON J JI Astron. J. PD JUN PY 1997 VL 113 IS 6 BP 2116 EP 2129 DI 10.1086/118423 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XC119 UT WOS:A1997XC11900016 ER PT J AU Stone, RC AF Stone, RC TI CCD astrometry of asteroids in the extragalactic reference frame SO ASTRONOMICAL JOURNAL LA English DT Article ID GUIDE STAR CATALOG; HIPPARCOS; MISSION; RADIO AB This paper describes observations of asteroids made with the Flagstaff Astrometric Scanning Transit Telescope (FASTT), which is a 20 cm CCD transit telescope that can observe objects brighter than V similar to 17.5 mag directly in the extragalactic reference frame. This is accomplished with differential reductions using ancillary FASTT observations of VI,BI radio reference objects [see Stone et al., AJ, 111, 1721 (1996) for more details]. Positions determined with the FASTT are accurate to +/-0.14 and +/-0.17 arcsec, respectively, in right ascension and declination for a single observation and are considerably more accurate than most positions determined for asteroids. Currently, the FASTT is observing asteroids for a number of projects that require very accurate positions. Namely, the FASTT is supporting the NEAR spacecraft mission by determining positions for the targeted asteroids 253 Mathilde and 433 Eros, and previously, FASTT observations of the asteroids 951 Gaspra and 243 Ida were made in support of the Galileo project. When compared with accurate JPL ephemerides computed for these asteroids, differences between FASTT observed and JPL calculated positions were generally small (<0.08 arcsec), and the rms scatter comparing these results was typically +/-0.18 arcsec in both coordinates. Moreover, the FASTT is observing a number of asteroids that are gravitationally interacting with other asteroids, and hopefully with enough observations, masses can be determined dynamically for some of them. There are only a few asteroids with accurate mass determinations. Approximately 1000 observations of these asteroids have been taken with the FASTT with an accuracy of similar to+/-0.16 arcsec in each coordinate. Finally, the FASTT is observing asteroids and stars that might be involved in occultation events. FASTT observations are being used to create accurate ephemerides for the asteroids involved as well as to determine very accurate positions for the background occultation stars. In particular, FASTT positional data were used in making the predictions for several recent successfully observed occultations (e.g., 654 Zelinda and 85 Io). RP Stone, RC (reprint author), USN OBSERV,FLAGSTAFF STN,POB 1149,FLAGSTAFF,AZ 86002, USA. NR 41 TC 7 Z9 7 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0004-6256 J9 ASTRON J JI Astron. J. PD JUN PY 1997 VL 113 IS 6 BP 2317 EP 2324 DI 10.1086/118442 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XC119 UT WOS:A1997XC11900035 ER PT J AU Dimond, E Peters, J Jenkins, J AF Dimond, E Peters, J Jenkins, J TI The genetic basis of cancer SO CANCER NURSING LA English DT Article ID ONCOGENES C1 NATL HUMAN GENOME RES INST,NIH,BETHESDA,MD 20889. RP Dimond, E (reprint author), NCI,USN,NATL NAVAL MED CTR,NIH,8901 WISCONSIN AVE,BLDG 8,ROOM 5101,BETHESDA,MD 20889, USA. NR 23 TC 7 Z9 7 U1 0 U2 0 PU LIPPINCOTT-RAVEN PUBL PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 SN 0162-220X J9 CANCER NURS JI Cancer Nurs. PD JUN PY 1997 VL 20 IS 3 BP 213 EP 226 DI 10.1097/00002820-199706000-00007 PG 14 WC Oncology; Nursing SC Oncology; Nursing GA XE572 UT WOS:A1997XE57200007 PM 9190096 ER PT J AU Porch, D AF Porch, D TI The military in politics and society in France and Germany in the twentieth century - Muller,KJ SO ENGLISH HISTORICAL REVIEW LA English DT Book Review RP Porch, D (reprint author), USN,POSTGRAD SCH,MONTEREY,CA 93940, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU LONGMAN GROUP UK LTD PI HARLOW PA LONGMAN HOUSE, BURNT MILL, HARLOW, ESSEX, ENGLAND CM20 2JE SN 0013-8266 J9 ENGL HIST REV JI Engl. Hist. Rev. PD JUN PY 1997 VL 112 IS 447 BP 808 EP 809 PG 2 WC History SC History GA XH139 UT WOS:A1997XH13900143 ER PT J AU Karmel, SM AF Karmel, SM TI The Chinese military's hunt for profits SO FOREIGN POLICY LA English DT Article C1 USN,POSTGRAD SCH,MONTEREY,CA. UNIV CALIF BERKELEY,BERKELEY,CA 94720. RP Karmel, SM (reprint author), UNIV LONDON LONDON SCH ECON & POLIT SCI,DEPT GOVT,LONDON WC2A 2AE,ENGLAND. NR 4 TC 5 Z9 5 U1 0 U2 1 PU CARNEGIE ENDOWMENT INTL PEACE PI WASHINGTON PA 2400 N STREET NW, WASHINGTON, DC 20037 SN 0015-7228 J9 FOREIGN POLICY JI Foreign Policy PD SUM PY 1997 IS 107 BP 102 EP 113 DI 10.2307/1149336 PG 12 WC International Relations SC International Relations GA XB680 UT WOS:A1997XB68000009 ER PT J AU Vogt, PR AF Vogt, PR TI Hummock fields in the Norway Basin and Eastern Iceland Plateau: Rayleigh-Taylor instabilities? SO GEOLOGY LA English DT Article AB Side-scan imagery and 3.5 kHz profiles in the Norway Basin reveal similar to 3-4 x 10(4) km(2) of sea floor covered by regularly spaced (500-2000 m), low-relief hummocks previously attributed to bottom currents. Extrapolating from nearby borehole data, I attribute these mound fields to gravitational (Rayleigh-Taylor) instabilities resulting from superposition of 50-100 m of thick Pliocene-Pleistocene, glacigenic (glacier-derived) sandy clays (density 1800 kg/m(3)) on a several-hundred-metre thickness of Miocene biosiliceous oozes having a density of 1300 kg/m(3). This hypothesis predicts or explains similar hummock fields in many oceanic regions where such density inversions exist. RP Vogt, PR (reprint author), USN,RES LAB,MARINE GEOSCI DIV,WASHINGTON,DC 20375, USA. NR 16 TC 19 Z9 19 U1 0 U2 0 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD JUN PY 1997 VL 25 IS 6 BP 531 EP 534 DI 10.1130/0091-7613(1997)025<0531:HFITNB>2.3.CO;2 PG 4 WC Geology SC Geology GA XC644 UT WOS:A1997XC64400013 ER PT J AU Davis, MA Kersey, AD AF Davis, MA Kersey, AD TI Simultaneous measurement of temperature and strain using fibre Bragg gratings and Brillouin scattering SO IEE PROCEEDINGS-OPTOELECTRONICS LA English DT Article DE optical fibres; temperature sensing; strain measurement ID FIBER AB The authors report on the simultaneous measurement of temperature and strain in a single optical fibre. The measurements were made using a combination of a fibre Bragg grating element and a Brillouin scattering interrogation system, operating in different optical wavelength regimes, to determine the two parameters. The system has the potential to provide quasi-distributed determination of strain and temperature along a fibre. RP Davis, MA (reprint author), USN,RES LAB,DIV OPT SCI,WASHINGTON,DC 20375, USA. NR 7 TC 23 Z9 23 U1 0 U2 2 PU IEE-INST ELEC ENG PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD, ENGLAND SG1 2AY SN 1350-2433 J9 IEE P-OPTOELECTRON JI IEE Proc.-Optoelectron. PD JUN PY 1997 VL 144 IS 3 BP 151 EP 155 DI 10.1049/ip-opt:19971271 PG 5 WC Engineering, Electrical & Electronic; Optics; Telecommunications SC Engineering; Optics; Telecommunications GA XJ774 UT WOS:A1997XJ77400006 ER PT J AU Rao, JBL Trunk, GV Patel, DP AF Rao, JBL Trunk, GV Patel, DP TI Two low-cost phased arrays SO IEEE AEROSPACE AND ELECTRONIC SYSTEMS MAGAZINE LA English DT Article AB In a phased array antenna, the phase shifters (or T/R modules in an active aperture phased array) with their beam-steering control circuitry along with the feed network account for the major hardware cost. This paper presents two antenna array configurations that use simpler feed, simpler phase-shifting and simpler beam-steering control circuitry for realizing low-cost phased arrays. Both are lens configurations. The first one uses a Radant lens, which provides a medium that is loaded with diodes and provides the needed phase shift by switching the diodes on and off. The other configuration employs a ferroelectric dielectric material whose dielectric constant can be varied with an applied DC bias voltage. It is shown that the ferroelectric lens may have further advantages of smaller thickness, simpler beam-steering controls and lower cost. RP Rao, JBL (reprint author), USN,RES LAB,DIV RADAR,WASHINGTON,DC 20375, USA. NR 7 TC 7 Z9 7 U1 1 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0885-8985 J9 IEEE AERO EL SYS MAG JI IEEE Aerosp. Electron. Syst. Mag. PD JUN PY 1997 VL 12 IS 6 BP 39 EP 44 DI 10.1109/62.587057 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA XA689 UT WOS:A1997XA68900009 ER PT J AU Felix, CL Meyer, JR Vurgaftman, I Lin, CH Murry, SJ Zhang, D Pei, SS AF Felix, CL Meyer, JR Vurgaftman, I Lin, CH Murry, SJ Zhang, D Pei, SS TI High-temperature 4.5-mu m type-II quantum-well laser with Auger suppression SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE optical pumping; pulsed lasers; quantum-well lasers; semiconductor device measurements; semiconductor device modeling; semiconductor lasers; wavelength measurement ID MU-M; LIFETIME AB Laser emission at 4.2-4.5 mu m has been observed at temperatures up to 310 K in pulsed optical pumping experiments on type-II quantum-well (QW) lasers with four constituents in each period (InAs-Ga1-xInxSb-InAs-AlSb). The characteristic temperature, T-0, is 41 K, and a peak output power exceeding 2 W/facet is observed at 200 K, The power conversion efficiency per facet of approximate to 0.2% up to 200 K is within a factor of 2 of the theoretical value, The 300 K Auger coefficient of 4 x 10(-27) cm(6)/s extracted from the threshold pump intensity demonstrates that Auger losses have been suppressed by a factor of four. C1 UNIV HOUSTON,CTR SPACE VACUUM EPITAXY,HOUSTON,TX 77204. RP Felix, CL (reprint author), USN,RES LAB,CODE 5613,WASHINGTON,DC 20375, USA. NR 16 TC 49 Z9 49 U1 2 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD JUN PY 1997 VL 9 IS 6 BP 734 EP 736 DI 10.1109/68.584973 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA XA049 UT WOS:A1997XA04900008 ER PT J AU Williams, KJ Esman, RD Williamson, S Valdmanis, J AlHemyari, K Rudd, JV AF Williams, KJ Esman, RD Williamson, S Valdmanis, J AlHemyari, K Rudd, JV TI Measurements of InGaAs metal-semiconductor-metal photodetector nonlinearities SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE microwave devices; nonlinear distortion; nonlinearities; optical communication; photodetectors; photodiodes ID MICROWAVE PHOTODETECTORS; FIELDS AB Nonlinearity measurements of microwave-bandwidth InGaAs metal-semiconductor-metal photodetectors have been performed. The devices show nonlinear characteristics which are similar to p-i-n structures despite a less-uniform electric field within the absorbing region, The nonlinear response versus applied voltage, nonlinearity growth rate versus current, nonlinearity threshold due to high power, and 1-dB compression current measurements presented here are all comparable in magnitude to their p-i-n counterparts. C1 PICOMETRIX INC,ANN ARBOR,MI 48105. RP Williams, KJ (reprint author), USN,RES LAB,CODE 5670,WASHINGTON,DC 20375, USA. NR 10 TC 3 Z9 3 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD JUN PY 1997 VL 9 IS 6 BP 812 EP 814 DI 10.1109/68.584999 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA XA049 UT WOS:A1997XA04900034 ER PT J AU Superczynski, MJ Waltman, DJ AF Superczynski, MJ Waltman, DJ TI Homopolar motor with high temperature superconductor field windings SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1996 Applied Superconductivity Conference CY AUG 25-30, 1996 CL PITTSBURGH, PA AB A superconducting field winding, assembled with discrete coils wound with Bismuth 2223 high temperature superconducting (HTS) wire, has been successfully operated in an electric homopolar motor designed and built by the Naval Surface Warfare Center. The motor's field winding is composed of two HTS coils fabricated by American Superconductor Corporation and two HTS coils fabricated by Intermagnetics General Corporation. These field winding coils were produced for the Navy under contracts with the Naval Research Center. At a HTS field winding operating temperature of 4.2 K, the motor produced 125 kW (167 hp) of output power. At a temperature of 28K, the motor power developed was 91 kW (122 hp). In comparison to other motor types, a homopolar motor provides an ideal operating environment for a superconducting magnet. The design, construction, and operating characteristics of this machine are described. Information describing the HTS field winding and its superconducting capabilities is presented along with that for the laboratory test facility used to measure the performance of the machine. Motor measured performance results and those predicted by computer simulation are compared and presented. An assessment of the state of the engineering development of HTS superconductors for magnet applications and recommendations for future development are made. RP Superczynski, MJ (reprint author), USN,CTR SURFACE WARFARE,CARDEROCK DIV,ANNAPOLIS,MD 21402, USA. NR 2 TC 24 Z9 25 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1997 VL 7 IS 2 BP 513 EP 518 DI 10.1109/77.614554 PN 1 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA XH864 UT WOS:A1997XH86400097 ER PT J AU Hazelton, DW Gardner, MT Rice, JA Walker, MS Trautwein, CM Haldar, P Gubser, DU Superczynski, M Waltman, D AF Hazelton, DW Gardner, MT Rice, JA Walker, MS Trautwein, CM Haldar, P Gubser, DU Superczynski, M Waltman, D TI HTS coils for the Navy's superconducting homopolar motor/generator SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1996 Applied Superconductivity Conference CY AUG 25-30, 1996 CL PITTSBURGH, PA AB We report here on the development of HTS coils at Intermagnetics for the Navy's homopolar motor / generator program. Two coil sizes were used. A series of small test coils (14.0 cm i.d. x 15.0 cm o.d. x 1.4 cm long) were employed to evaluate various conductor winding, insulation and epoxy impregnation issues. Based upon the results of these test coils, the larger coil modules (19.37 cm i.d. x 24.45 cm o.d. x 2.54 cm long) for the homopolar motor / generator were fabricated. Several coils each of three types of react-and-wind coils were produced, one type with monocore BSCCO-2223, one type with multifilamentary BSSCO-2223 and the other type with surface coated BSCCO-2212. Test results are presented as well as discussions on various coil technology issues. C1 USN,RES LAB,WASHINGTON,DC 20375. USN,CTR SURFACE WARFARE,ANNAPOLIS DETACHMENT,ANNAPOLIS,MD 21402. RP Hazelton, DW (reprint author), INTERMAGNET GEN CORP,LATHAM,NY 12110, USA. NR 1 TC 15 Z9 15 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1997 VL 7 IS 2 BP 664 EP 667 DI 10.1109/77.614591 PN 1 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA XH864 UT WOS:A1997XH86400134 ER PT J AU Claassen, JH AF Claassen, JH TI Measurement of the critical current and flux creep parameters in thin superconducting films using the single coil technique SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1996 Applied Superconductivity Conference CY AUG 25-30, 1996 CL PITTSBURGH, PA ID RELAXATION; VORTICES AB A non-contacting method of determining the critical current of a superconducting film has proven useful in several laboratories as a routine indicator of HTS film quality. It consists of a small coil pressed against the film surface and driven with an audio frequency sine wave current (I-drive). The onset of a significant third harmonic voltage component (V-3f) across the coil indicates that the screening currents in the film have exceeded their critical value, We show in this paper that the quantity V-3f/(f I-drive) should be a universal function of I-drive/I-sc if the Bean critical state model is applicable, Here I-sc is a scaling current that is proportional to J(c)d (J(c)=critical current density in the film, d is its thickness) and f is the frequency, By varying the temperature of a thin YBCO film between 4.2 K and its transition, this scaling was observed to apply over a range of J(c)'s covering two decades and drive frequencies covering more than three decades, The frequency dependent measurements revealed a logarithmic dependence of the critical current on frequency that can be interpreted as a manifestation of flux creep, This data was used to infer the pinning energy within the collective pinning model. RP Claassen, JH (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 5 TC 7 Z9 7 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1997 VL 7 IS 2 BP 1463 EP 1466 DI 10.1109/77.620848 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA XH866 UT WOS:A1997XH86600087 ER PT J AU Francavilla, TL Fisher, MA Allen, LH Cukauskas, EJ Soulen, RJ AF Francavilla, TL Fisher, MA Allen, LH Cukauskas, EJ Soulen, RJ TI Modeling of temperature dependent current-voltage curves of YBCO/Ag composites SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1996 Applied Superconductivity Conference CY AUG 25-30, 1996 CL PITTSBURGH, PA ID VORTEX-GLASS SUPERCONDUCTIVITY; FILMS AB We have measured the current-voltage (I-V) characteristics of thin film composites made from YBa2Cu3O7-x (YBCO) and Ag. When deposited upon a substrate, this material appears to form arrays of superconducting-normal-superconducting (SNS) junctions. To make these measurements, the films were patterned into microbridges and immersed directly into the cryogen to provide a constant temperature environment and to avoid problems of local heating. The data were fitted by several phenomenological models in an effort to understand the dissipation mechanism appropriate to these materials. RP Francavilla, TL (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1997 VL 7 IS 2 BP 1646 EP 1649 DI 10.1109/77.620893 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA XH866 UT WOS:A1997XH86600132 ER PT J AU Allen, LH Cukauskas, EJ AF Allen, LH Cukauskas, EJ TI Au/YBa2Cu3O7-delta thin film composites on various substrates SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1996 Applied Superconductivity Conference CY AUG 25-30, 1996 CL PITTSBURGH, PA AB We have grown a series of composite films of Au with YBa2Cu3O7-delta on various substrates using a bilayer deposition technique to study their suitability for flux flow applications. The T-c's and J(c)'s were measured, and results compared with plain YBCO films for the different substrates. The patterning process resulted in some damage to the composites, but an oxygen plasma treatment was effective in restoring T-c's and resistance ratios, J(c) measurements suggest that Au/YBCO composites behave like SNS-coupled arrays of superconducting grains. Their increased response to small magnetic fields is consistent with Josephson vortices dominating the transport. These findings indicate that Au/YBCO composites are a promising material for flux flow applications. RP Allen, LH (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 11 TC 3 Z9 3 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1997 VL 7 IS 2 BP 1650 EP 1653 DI 10.1109/77.620894 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA XH866 UT WOS:A1997XH86600133 ER PT J AU Cukauskas, EJ Allen, LH Pond, J AF Cukauskas, EJ Allen, LH Pond, J TI Off-axis co-sputtered YBCO and CeO2 thin films SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1996 Applied Superconductivity Conference CY AUG 25-30, 1996 CL PITTSBURGH, PA ID FLUX-FLOW TRANSISTORS; CURRENT GAIN; YBA2CU3O7-DELTA; TEMPERATURE AB We have investigated the properties of off-axis cosputtered films of YBCO and CeO2 having CeO2 concentrations up to 43%, Morphology investigations suggest that films with more than 29% CeO2 may consist of a new material phase, T-c and resistance ratio decreased with increasing CeO2 concentration, Degradation of T-c after photoresist processing the films was observed and reversed by a 20 minute oxygen plasma etch. The temperature dependence of the critical current near T-c showed two power law dependence regions with a crossover near 0.99 T-c for films having low concentrations of CeO2. I-c's were decreased by smalt ap plied magnetic fields, and for some samples the response was observed to increase at lower temperature. For a sample having 26% CeO2, a 40% reduction in critical current was observed for a 2 Gauss applied field. This response indicates that this may be a candidate material for the development of Josephson vortex flow devices. RP Cukauskas, EJ (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 17 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1997 VL 7 IS 2 BP 1654 EP 1657 DI 10.1109/77.620895 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA XH866 UT WOS:A1997XH86600134 ER PT J AU Pond, JM Allen, LH Cukauskas, EJ AF Pond, JM Allen, LH Cukauskas, EJ TI A simple technique for measuring the transition temperature at microwave frequencies SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1996 Applied Superconductivity Conference CY AUG 25-30, 1996 CL PITTSBURGH, PA ID SUSCEPTIBILITY APPARATUS; FILMS; SAMPLES AB A technique is described which enables contactless measurements at microwave frequencies of the superconducting transition. The approach employs an electrically small microwave loop antenna to sense the change in the reflected microwave signal as flux is expelled, due to the Meissner effect, from the superconductor. Advantages of this technique include the ability to measure small areas of a superconducting thin film after photolithographic patterning into a device geometry. This approach is very sensitive in the frequency range from 0.05 GHz to 5 GHz and for some YBCO films a dependence of the transition temperature width on frequency has been observed. Such frequency-dependent signatures may provide valuable information regarding improvements in film deposition and device processing. RP Pond, JM (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 10 TC 4 Z9 4 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1997 VL 7 IS 2 BP 1857 EP 1860 DI 10.1109/77.620946 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA XH866 UT WOS:A1997XH86600184 ER PT J AU Chrisey, DB Osofsky, MS Horwitz, JS Soulen, RJ Woodfield, B Byers, J Daly, GM Dorsey, PC Pond, JM Johnson, M Auyeung, RCY AF Chrisey, DB Osofsky, MS Horwitz, JS Soulen, RJ Woodfield, B Byers, J Daly, GM Dorsey, PC Pond, JM Johnson, M Auyeung, RCY TI Evidence for modification of the superconducting order parameter in YBa2Cu3O7-delta films by injection of a spin polarized current SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1996 Applied Superconductivity Conference CY AUG 25-30, 1996 CL PITTSBURGH, PA AB We have deposited novel bilayer thin films of a ferromagnetic material and YBa2Cu3O7 separated by a thin Au diffusion barrier to study the effects of a spin polarized nonequilibrium quasiparticle population on the superconducting order parameter, Thin films of YBa2Cu3O7-delta, Au, and permalloy (Ni,,Fe,,) were deposited by pulsed laser deposition onto (100) MgO, SrTiO3 or LaAlO3 substrates. A thin stripe of YBa2Cu3O7-delta was patterned and two pairs of Au cross stripes for current and voltage contact were deposited at each end. Between these contacts a permalloy and a Au cross stripe was also deposited to serve as polarized and unpolarized quasiparticle injection sources, respectively. Utilizing this pseudo-three terminal device configuration we have in some samples measured reductions in the ferromagnet contact as compared to the normal metal contact. Details of this experiment, issues for optimized fabrication, and theoretical issues are discussed. C1 SFA INC,LARGO,MD 20774. RP Chrisey, DB (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. RI Osofsky, Michael/A-1050-2010 NR 12 TC 20 Z9 20 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1997 VL 7 IS 2 BP 2067 EP 2070 DI 10.1109/77.620997 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA XH866 UT WOS:A1997XH86600234 ER PT J AU Daly, GM Pond, JM Osofsky, MS Horwitz, JS Soulen, RJ Chrisey, DB Auyeung, RCY AF Daly, GM Pond, JM Osofsky, MS Horwitz, JS Soulen, RJ Chrisey, DB Auyeung, RCY TI Pulsed laser deposition of patterned multilayers for HTS device fabrication SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1996 Applied Superconductivity Conference CY AUG 25-30, 1996 CL PITTSBURGH, PA ID SUPERCONDUCTING WEAK LINKS AB Pulsed laser deposition (PLD) has been used to deposit high quality multilayer thin films of Permalloy/Au/YBCO onto (100) oriented substrates of MgO and SrTiO3. These multilayer structures are currently being used to investigate the effect of the injection of polarized electrons on the order parameter of high temperature superconducting (HTS) thin films. To observe this effect, thin films with sharp interfaces (to minimize spin scattering) and low contact resistance will be required. The morphology and structure of the deposited films has been investigated using scanning electron microscopy and x-ray diffraction, respectively. The electrical properties (T-c and J(c) (77 K, B = 0)) were measured for both unpatterned and patterned films. Films were patterned using both wet chemical and ion beam (Ar+, 1 KeV) techniques. Unpatterned films were characterized inductively as having T-c's > 88 K and J(c)'s > 1 MA/cm(2). Wet chemical etching resulted in films with slightly reduced T-c's and J(c)'s similar to 10(3) - 10(4) A/cm(2) however, no reduction in T-c or J(c) was observed for dry etching. A lift off procedure using PMMA/Cu has been explored to define smaller (similar to 400 mu m) features. Extremely low contact resistance's (< 10(7) Omega cm(2)) have been measured for Au films deposited by PLD onto YBCO. The low contact resistance is attributed to the high kinetic of the Au particles. These device structures can be used to develop simple HTS based transistors. C1 SFA INC, LARGO, MD 20774 USA. RP Daly, GM (reprint author), USN, RES LAB, WASHINGTON, DC 20375 USA. RI Osofsky, Michael/A-1050-2010 NR 14 TC 2 Z9 2 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1997 VL 7 IS 2 BP 2153 EP 2156 DI 10.1109/77.621019 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA XH866 UT WOS:A1997XH86600256 ER PT J AU Pond, JM AF Pond, JM TI A computationally efficient approach to microwave circuit modeling of complex high temperature superconductor circuits SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1996 Applied Superconductivity Conference CY AUG 25-30, 1996 CL PITTSBURGH, PA ID TRANSMISSION-LINES AB A computationally efficient approach to modeling complex high temperature superconductor (HTS) microwave circuits is described which combines two-dimensional electromagnetic solutions of microwave transmission lines, incorporating a phenomenological description of HTS behavior, with conventional commercially available microwave-circuit computer-aided-design software. Internal inductance effects are known to have a substantial impact on the design and implementation of narrowband HTS circuits. Phase velocities and characteristic impedances can be well modeled using a phenomenological description of HTS superconductivity along with a generalized approximate boundary condition and a two dimensional electromagnetic solution to the waveguiding structure. Resultant parameterized design equations can then be incorporated into standard commercially available microwave-circuit computer-aided-design software. The test case examined in detail was the superconducting channelized receiver delivered by the Naval Research Laboratory to Phase II of the High Temperature Superconducting Space Experiment. Excellent agreement was obtained between measurements made on the demultiplexer and this HTS microwave circuit modeling approach. RP Pond, JM (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1997 VL 7 IS 2 BP 3052 EP 3055 DI 10.1109/77.621976 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA XH867 UT WOS:A1997XH86700190 ER PT J AU Gulian, AM VanVechten, D AF Gulian, AM VanVechten, D TI Possible three terminal HTS transistor device SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1996 Applied Superconductivity Conference CY AUG 25-30, 1996 CL PITTSBURGH, PA ID QUASIPARTICLE POTENTIAL DIFFERENCE; NONEQUILIBRIUM SUPERCONDUCTORS; FILMS; INJECTION AB A non-zero, gauge invariant potential,LI has been recognized since 1972 to occur in superconductors in various non-equilibrium circumstances. at is central to the description of the time dependent properties Non-zero values of this potential cause gap suppression, Thus if the local value of the potential Ir san be made sufficiently large, the material can be locally snitched into the normal state. Superfluid flow mould no longer exist and a voltage would Pre required to sustain a preexisting current The S to N switching time is expected to he wb-picosecond for Nb and faster for the HTS materials, The rime scale for the restoration of superconductivity will he set by the dynamic branch mixing time, sub-nanosecond for Nb. Thus the main difficulty in designing a superconducting transistor analog using this effect is in producing a sufficiently large value of mu. We suggest that an appropriate mechanism is provided by the injection of a current of predominantly electron- or hole-like character from a doped non-degenerate semiconductor into a thin, current carrying superconducting film. C1 OFF NAVAL RES,ARLINGTON,VA 22217. RP Gulian, AM (reprint author), ARMENIAN ACAD SCI,INST PHYS RES,ASHTARAK 378410,ARMENIA. NR 22 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1997 VL 7 IS 2 BP 3096 EP 3098 DI 10.1109/77.621987 PN 3 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA XH867 UT WOS:A1997XH86700201 ER PT J AU Clem, TR Froelich, MC Overway, DJ Purpura, JW Wiegert, RF Koch, RH Lathrop, DK Rozen, J Eraker, JH Schmidt, JM AF Clem, TR Froelich, MC Overway, DJ Purpura, JW Wiegert, RF Koch, RH Lathrop, DK Rozen, J Eraker, JH Schmidt, JM TI Advances in sensor development and demonstration of superconducting gradiometers for mobile operation SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1996 Applied Superconductivity Conference CY AUG 25-30, 1996 CL PITTSBURGH, PA ID DC-SQUID; 77 K; NOISE; MAGNETOMETER AB During the 1980's a SQUID-based superconducting gradiometer prototype utilizing bulk niobium and wire superconducting components cooled by liquid helium was developed by the U,S. Navy, This sensor was successfully utilized in demonstrations for sea mine countermeasures and for the detection of UneXploded Ordnance (UXO), Advances in this sensor technology are being pursued for longer detection ranges and for more versatile operation, An advanced sensor prototype using all thin film niobium circuits and a new liquid helium cooling concept has been built to provide significant increases in sensitivity, In addition, a high Tc sensor concept using liquid nitrogen refrigeration has been developed to reduce package size and to simplify logistic and support requirements for field operation. This paper will review the current status and plans of this program, specifically describing the recent advances in sensor development and results from the demonstration to detect UXO. C1 IBM CORP,TJ WATSON RES CTR,YORKTOWN HTS,NY 10598. BALL AEROSP & TECHNOL CORP,BOULDER,CO 80306. CONDUCTUS INC,SUNNYVALE,CA 94086. RP Clem, TR (reprint author), USN,CTR SURFACE WARFARE,DAHLGREN DIV,COASTAL SYST STN,PANAMA CITY,FL 32407, USA. NR 21 TC 10 Z9 10 U1 1 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1997 VL 7 IS 2 BP 3287 EP 3293 DI 10.1109/77.622056 PN 3 PG 7 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA XH867 UT WOS:A1997XH86700247 ER PT J AU Koller, D VanVechten, D Blamire, MG Wood, KS Fritz, GG Horwitz, JS Daly, GM Thrasher, JB Pinto, JF Gyulamiryan, AL Vartanyan, VH Akopyan, RB Gulian, AM AF Koller, D VanVechten, D Blamire, MG Wood, KS Fritz, GG Horwitz, JS Daly, GM Thrasher, JB Pinto, JF Gyulamiryan, AL Vartanyan, VH Akopyan, RB Gulian, AM TI Development of a new superconducting detector for the ultra-violet and soft x-ray regimes SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1996 Applied Superconductivity Conference CY AUG 25-30, 1996 CL PITTSBURGH, PA AB UV and X-ray astronomy need hyperspectral imaging devices, i.e. large format (1000 x 1000) arrays of pixels in which each single-photon event is tagged with spectral information. Such devices permit multicolor imagery and surveys to be obtained with a single camera. Here we discuss the first-stage of development of a new generation of UV/X-ray detectors that will provide 0.1-0.01% energy resolution in an array format. C1 US OFF NAVAL RES,ARLINGTON,VA. UNIV CAMBRIDGE,CAMBRIDGE,ENGLAND. PHYS RES INST,ASHTARAK,ARMENIA. RP Koller, D (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 10 TC 1 Z9 1 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1997 VL 7 IS 2 BP 3391 EP 3394 DI 10.1109/77.622104 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA XH867 UT WOS:A1997XH86700272 ER PT J AU VanVechten, D Wood, KS Koller, D Gulian, AM Nikogosian, VR AF VanVechten, D Wood, KS Koller, D Gulian, AM Nikogosian, VR TI High energy photon absorption in superconductors results in branch imbalance potential SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1996 Applied Superconductivity Conference CY AUG 25-30, 1996 CL PITTSBURGH, PA AB When a superconductor is disturbed by a high energy deposition, an asymmetry in the distributions of electron-like and hole-like excitations results. This manifests itself as a voltage output, which can be measured in different ways. Here we study the behavior of this quantity using the kinetic equations to model the energy cascade. Special attention is paid to the similarity and differences between the behaviors of normal metals and superconductors. The particular case of tantalum is considered in the modeling. C1 PHYS RES INST,ASHTARAK,ARMENIA. RP VanVechten, D (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 12 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1997 VL 7 IS 2 BP 3419 EP 3421 DI 10.1109/77.622115 PN 3 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA XH867 UT WOS:A1997XH86700279 ER PT J AU Reuter, M AF Reuter, M TI Numerically efficient Fourier-based technique for calculating error probabilities with intersymbol interference SO IEEE TRANSACTIONS ON COMMUNICATIONS LA English DT Article DE intersymbol interference; probability of error ID COCHANNEL INTERFERENCE AB We propose a numerically efficient technique for calculating the probability of symbol error for arbitrary coherent modulation schemes in the presence of intersymbol interference (ISI) and additive noise, The probability of error is formulated in terms of an inverse Fourier transform of the windowed characteristic function of the random variable representing the interfering symbols and the noise process, The integral is evaluated numerically using the sampling theorem. C1 UNIV CALIF SAN DIEGO,DEPT ELECT & COMP ENGN,LA JOLLA,CA 92093. RP Reuter, M (reprint author), USN,COMMAND CONTROL & OCEAN SURVEILLANCE CTR,RDT&E DIV,CODE D855,SAN DIEGO,CA 92152, USA. NR 13 TC 14 Z9 14 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0090-6778 J9 IEEE T COMMUN JI IEEE Trans. Commun. PD JUN PY 1997 VL 45 IS 6 BP 629 EP 632 DI 10.1109/26.592592 PG 4 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA XF020 UT WOS:A1997XF02000002 ER PT J AU McEachen, JC Duncan, JS AF McEachen, JC Duncan, JS TI Shape-based tracking of left ventricular wall motion SO IEEE TRANSACTIONS ON MEDICAL IMAGING LA English DT Article DE cardiac left ventricular motion; contrast ventriculograph; echocardiograph; linear filtering; magnetic resonance imaging (MRI); nonrigid motion ID HUMAN-HEART; MODEL; IMAGES AB 1An approach for tracking and quantifying the nonrigid, nonuniform motion of the left ventricular (LV) endocardial wall from two-dimensional (2-D) cardiac image sequences, on a point-by-point basis over the entire cardiac cycle, is presented, Given a set of boundaries, motion computation involves first matching local segments on one contour to segments on the next contour in the sequence using a shape-based strategy, Results from the match process are incorporated with a smoothness term into an optimization functional, The global minimum of this functional is found, resulting in a smooth flow field that is consistent with the match data, The computation is performed for all pairs of frames in the temporal sequence and equally sampled points on one contour are tracked throughout the sequence, resulting in a composite flow field over the entire sequence. Two perspectives on characterizing the optimization functional are presented which result in a tradeoff resolved by the confidence in the initial boundary segmentation, Experimental results for contours derived from diagnostic image sequences of three different imaging modalities are presented, A comparison of trajectory estimates with trajectories of gold-standard markers implanted in the LV wall are presented for validation, The results of this comparison confirm that although cardiac motion is a three-dimensional (3-D) problem, two-dimensional (2-D) analysis provides a rich testing ground for algorithm development. C1 YALE UNIV, DEPT DIAGNOST RADIOL, NEW HAVEN, CT 06520 USA. YALE UNIV, DEPT ELECT ENGN, NEW HAVEN, CT 06520 USA. RP McEachen, JC (reprint author), USN, POSTGRAD SCH, DEPT ELECT & COMP ENGN, MONTEREY, CA 93943 USA. FU NHLBI NIH HHS [2R01HL44803]; NLM NIH HHS [1F37LM00041-01] NR 33 TC 79 Z9 79 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0278-0062 EI 1558-254X J9 IEEE T MED IMAGING JI IEEE Trans. Med. Imaging PD JUN PY 1997 VL 16 IS 3 BP 270 EP 283 DI 10.1109/42.585761 PG 14 WC Computer Science, Interdisciplinary Applications; Engineering, Biomedical; Engineering, Electrical & Electronic; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Computer Science; Engineering; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA XC715 UT WOS:A1997XC71500004 PM 9184889 ER PT J AU Raman, S Rucky, F Rebeiz, GM AF Raman, S Rucky, F Rebeiz, GM TI A high-performance W-band uniplanar subharmonic mixer SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article DE coplanar waveguide; millimeter-wave mixer; MMIC's; subharmonic mixers ID RECEIVER; NOISE AB A uniplanar subharmonic mixer has been implemented in coplanar waveguide (CPW) technology. The circuit is designed to operate at RF frequencies of 92-96 GHz, IF frequencies of 2-4 GHz, and LO frequencies of 45-46 GHz. Total circuit size excluding probe pads and transitions is less than 0.8 mm x 1.5 mm, The measured minimum single-sideband (SSB) conversion loss is 7.0 dB at an RF of 94 GHz, and represents state-of-the-art performance for a planar W-band subharmonic mixer, The mixer is broad-band with a SSB conversion loss of less than 10 dB over the 83-97-GHz measurement band, The measured LO-RF isolation is better than -40 dB for LO frequencies of 45-46 GHz. The double-sideband (DSB) noise temperature measured using the Y-factor method is 725 K at an LO frequency of 45.5 GHz and an IF frequency of 1.4 GHz. The measured data agrees well with the predicted performance using harmonic-balance analysis (HBA), Potential applications are millimeter-wave receivers for smart munition seekers and automotive-collision-avoidance radars. C1 USN, CTR SURFACE WARFARE, DAHLGREN DIV, DAHLGREN, VA 22448 USA. RP Raman, S (reprint author), UNIV MICHIGAN, DEPT COMP SCI & ELECT ENGN, RADIAT LAB, ANN ARBOR, MI 48109 USA. NR 16 TC 50 Z9 51 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9480 EI 1557-9670 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD JUN PY 1997 VL 45 IS 6 BP 955 EP 962 DI 10.1109/22.588609 PG 8 WC Engineering, Electrical & Electronic SC Engineering GA XD039 UT WOS:A1997XD03900012 ER PT J AU King, SE Aakenes, UR McCoy, K Phillips, GW AF King, SE Aakenes, UR McCoy, K Phillips, GW TI Development of the arctic radionuclide monitoring station SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 1996 Nuclear Science Symposium and Medical Imaging Conference CY NOV 03-09, 1996 CL ANAHEIM, CA AB In recent years, the world has learned about the dumping of nuclear reactors and other waste into the Arctic seas by the former Soviet Union. Most of the information on the present levels of radioactivity in the region has been obtained by oceanographic expeditions conducted during the brief Arctic summers. Year-round monitoring of the movement of radioactivity during dynamic seasonal and episodic chances is hampered by the difficulties caused by sea ice, logistics and communication constraints associated with deployment and maintenance of monitoring equipment in this remote region. We have designed an autonomous station to measure the benthic gamma-ray emitting radioactivity for periods of at least one year. The station is capable of detecting a 30 Bq/m(3) increase in the Cs-137 activity in a 24 hour period. After a year-long deployment, the station releases its anchor and rises to the surface to transmit the accumulated spectra and oceanographic data via an Argos satellite link. The design and performance characteristics of the prototype station will be discussed. C1 OCEANOR,N-7005 TRONDHEIM,NORWAY. OCEAN SENSORS,SAN DIEGO,CA 92121. RP King, SE (reprint author), USN,RES LAB,CODE 6616,4555 OVERLOOK AVE SW,WASHINGTON,DC 20375, USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD JUN PY 1997 VL 44 IS 3 BP 777 EP 782 DI 10.1109/23.603751 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA XF302 UT WOS:A1997XF30200096 ER PT J AU Kroeger, RA Grove, JE Inderhees, SE Johnson, WN Kinzer, RL Kurfess, JD Phlips, BP AF Kroeger, RA Grove, JE Inderhees, SE Johnson, WN Kinzer, RL Kurfess, JD Phlips, BP TI Thin scintillators and position sensitive photomultiplier tubes for hard X-ray imaging in space SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 1996 Nuclear Science Symposium and Medical Imaging Conference CY NOV 03-09, 1996 CL ANAHEIM, CA AB Monolithic and segmented CsI(TI) scintillators coupled to a position sensitive photomultiplier tube (PSPMT) have been tested for imaging and environmental performance necessary for hard X-ray astrophysics missions. Using a crossed-wire PSPMT and individual anode-wire readout, spatial resolution of 1-2 mm rms at 60 keV over the entire photo-cathode imaging surface is obtained out to near the edges of the scintillator. A PSPMT mapping correction was used to obtain energy resolution close to what is expected from CsI(Tl) scintillators. C1 UNIV SPACE RES ASSOC,WASHINGTON,DC. RP Kroeger, RA (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. RI Johnson, Neil/G-3309-2014 NR 4 TC 11 Z9 11 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD JUN PY 1997 VL 44 IS 3 BP 881 EP 884 DI 10.1109/23.603770 PN 1 PG 4 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA XF302 UT WOS:A1997XF30200115 ER PT J AU Sarkar, N Yun, XP Kumar, V AF Sarkar, N Yun, XP Kumar, V TI Dynamic control of 3-D rolling contacts in two-arm manipulation SO IEEE TRANSACTIONS ON ROBOTICS AND AUTOMATION LA English DT Article DE dextrous manipulation; grasping; rolling contact; two-arm manipulation ID MULTIFINGERED HANDS; KINEMATICS; STABILITY; SYSTEMS; MOTION; ROBOT AB When two or more arms are used to manipulate a large object, it is preferable not to have a rigid grasp in order to gain more dexterity in manipulation. It may therefore be necessary to control contact motion between the object and the effector(s) on one or more arms, This paper addresses the dynamic control of two arms cooperatively manipulating a large object with rolling contacts, In the framework presented here, the motion of the object as well as the loci of the contact point either on the surface of each effector or on the object can be directly controlled, The velocity and acceleration equations for three dimensional rolling contacts are derived in order to obtain a dynamic model of the system, A nonlinear feedback control algorithm that decouples and linearizes the system is developed, This is used to demonstrate the control of rolling motion along each arm and the adaptation of grasps to varying loads. C1 USN,POSTGRAD SCH,DEPT ELECT & COMP ENGN,MONTEREY,CA 93943. UNIV PENN,DEPT MECH ENGN & APPL MECH,PHILADELPHIA,PA 19104. RP Sarkar, N (reprint author), UNIV HAWAII,DEPT MECH ENGN,HONOLULU,HI 96822, USA. NR 37 TC 33 Z9 35 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1042-296X J9 IEEE T ROBOTIC AUTOM JI IEEE Trans. Robot. Autom. PD JUN PY 1997 VL 13 IS 3 BP 364 EP 376 DI 10.1109/70.585899 PG 13 WC Automation & Control Systems; Engineering, Electrical & Electronic; Robotics SC Automation & Control Systems; Engineering; Robotics GA XB584 UT WOS:A1997XB58400005 ER PT J AU Lee, N Schwartz, SC AF Lee, N Schwartz, SC TI Robustness of oversampled gabor transient detectors: A comparison of energy and known location detectors SO IEEE TRANSACTIONS ON SIGNAL PROCESSING LA English DT Article ID PERFORMANCE ANALYSIS; REPRESENTATION; TRANSFORM; SIGNAL AB This correspondence provides a ''context'' for previous studies on the use of linear time-frequency transforms for transient signal detection in the case where signal component locations are assumed to be known. The robustness of a known-location detector (KLD) based on the oversampled Gabor transform is compared with that of the corresponding energy detector in the Gabor domain. As expected, the KLD was sensitive to location mismatch; unexpectedly, it was extremely sensitive to location mismatch. C1 PRINCETON UNIV, DEPT ELECT ENGN, PRINCETON, NJ 08544 USA. RP USN, UNDERSEA WELF CTR, NEWPORT, RI 02841 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1053-587X EI 1941-0476 J9 IEEE T SIGNAL PROCES JI IEEE Trans. Signal Process. PD JUN PY 1997 VL 45 IS 6 BP 1638 EP 1641 DI 10.1109/78.600004 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA XC731 UT WOS:A1997XC73100020 ER PT J AU Wiest, DL Ashe, JM Howcroft, TK Lee, HM Kemper, DM Negishi, I Singer, DS Singer, A Abe, R AF Wiest, DL Ashe, JM Howcroft, TK Lee, HM Kemper, DM Negishi, I Singer, DS Singer, A Abe, R TI A spontaneously arising mutation in the DLAARN motif of murine ZAP-7O abrogates kinase activity and arrests thymocyte development SO IMMUNITY LA English DT Article ID CELL ANTIGEN RECEPTOR; PROTEIN-TYROSINE KINASE; SEVERE COMBINED IMMUNODEFICIENCY; IMMATURE CD4+CD8+ THYMOCYTES; SIGNAL-TRANSDUCTION; MONOCLONAL-ANTIBODY; ZETA-CHAIN; PHOSPHOLIPASE C-GAMMA-1; NEGATIVE SELECTION; T-CELLS AB Development of immature CD4(+)CD8(+) thymocytes into functionally mature CD4(+) and CD8(+) T cells is driven by selection events that require signals transduced through the T cell antigen receptor (TCR). Transduction of TCR signals in the thymus involves tyrosine phosphorylation of the protein tyrosine kinase ZAP-70 by p56(lck) and results in induction of ZAP-70 enzymatic activity. We have identified a novel, spontaneously arising point mutation within a highly conserved motif (DLAARN) in the kinase domain of murine ZAP-70 that uncouples tyrosine phosphorylation of ZAP-70 from induction of ZAP-70 kinase activity. Mice homozygous for this mutation are devoid of mature T cells because thymocyte development is arrested at the CD4(+)CD8(+) stage of differentiation. The developmental arrest is due to the inability of CD4(+)CD8(+) thymocytes to propagate TCR signals in the absence of ZAP-70 kinase activity despite tyrosine phosphorylation of TCR-associated ZAP-70 molecules. C1 NCI, EXPT IMMUNOL BRANCH, NIH, BETHESDA, MD 20892 USA. USN, MED RES INST, IMMUNE CELL BIOL DEPT, BETHESDA, MD 20889 USA. NIPPON ROCHE RES CTR, KAMAKURA, KANAGAWA 247, JAPAN. SCI UNIV TOKYO, RES INST BIOL SCI, DIV IMMUNOBIOL, TOKYO, CHIBA 278, JAPAN. OI Wiest, David/0000-0002-0792-3188 NR 45 TC 62 Z9 64 U1 0 U2 0 PU CELL PRESS PI CAMBRIDGE PA 600 TECHNOLOGY SQUARE, 5TH FLOOR, CAMBRIDGE, MA 02139 USA SN 1074-7613 EI 1097-4180 J9 IMMUNITY JI Immunity PD JUN PY 1997 VL 6 IS 6 BP 663 EP 671 DI 10.1016/S1074-7613(00)80442-2 PG 9 WC Immunology SC Immunology GA XG579 UT WOS:A1997XG57900002 PM 9208839 ER PT J AU Smith, EA Kimmel, EC Bowen, LE Reboulet, JE Carpenter, RL AF Smith, EA Kimmel, EC Bowen, LE Reboulet, JE Carpenter, RL TI Preliminary assessment of a pyrotechnically generated aerosol fire suppressant SO INHALATION TOXICOLOGY LA English DT Article AB Fischer 344 rats (approximately 250-300 g) were exposed to the aerosol resulting from the pyrolysis of SFE Formulation A at a loading of 50 or 80 g/m(3). Animals were exposed for 15 or 60 min and euthanized 1 h postexposure. The exposures were conducted in a 700-L inhalation chamber under static conditions. Aerosol samples were collected and analyzed for mass concentration and size distribution (mass median aerodynamic diameter, MMAD, and geometric standard deviation, sigma(g)). Lungs were collected for wet/dry weight ratio analysis, and nasal turbinates were prepared for histopathology examination. No deaths occurred during the study or postexposure observation period. Animals exposed to SFE exhibited signs of dyspnea, lack of coordination, and lethargy. As the load and exposure length increased, these signs became more pronounced. No lesions were noted in the trachea, lung, heart, and abdominal organs upon gross examination. No histopathological abnormalities were noted in the nasal turbinates. Changer in blood gases, blood pH, the various hemoglobin types, and serum glucose were noted. Of these changes, carboxyhemoglobin was the most significant, with an increase of 40%. The remaining serum chemistry parameters evaluated were within their respective biological ranges. Wet/dry lung ratio showed no difference between control and exposure groups. C1 NMRI,TD,GEO CTR INC,WRIGHT PATTERSON AFB,OH. RP Smith, EA (reprint author), USN,MED RES INST DETACHMENT TOXICOL,2612 5TH ST,AREA B,WRIGHT PATTERSON AFB,OH 45433, USA. NR 15 TC 3 Z9 3 U1 0 U2 1 PU TAYLOR & FRANCIS PI BRISTOL PA 1900 FROST ROAD, SUITE 101, BRISTOL, PA 19007-1598 SN 0895-8378 J9 INHAL TOXICOL JI Inhal. Toxicol. PD JUN-JUL PY 1997 VL 9 IS 5 BP 449 EP 463 PG 15 WC Toxicology SC Toxicology GA XG092 UT WOS:A1997XG09200004 ER PT J AU Rennert, P Furlong, K Jellis, C Greenfield, E Freeman, GJ Ueda, Y Levine, B June, CH Gray, GS AF Rennert, P Furlong, K Jellis, C Greenfield, E Freeman, GJ Ueda, Y Levine, B June, CH Gray, GS TI The IgV domain of human B7-2 (CD86) is sufficient to co-stimulate T lymphocytes and induce cytokine secretion SO INTERNATIONAL IMMUNOLOGY LA English DT Article DE B7-1; CD28; CD80; CD86; CTLA-4; cytokine; fusion proteins; IgV; soluble ligand ID ACTIVATION ANTIGEN B7; CELL ACTIVATION; GENOMIC ORGANIZATION; CD28 RECEPTOR; 2ND RECEPTOR; CTLA-4; EXPRESSION; COSTIMULATION; INTERLEUKIN-2; BINDING AB B7-1 (CD80) and B7-2 (CD86) are genetically and structurally related molecules expressed on antigen-presenting cells. Both bind CD28 to co-stimulate T lymphocytes, resulting in proliferation and cytokine production. The extracellular portions of B7-1 and B7-2 which bind to CD28 and CTLA-4 are related to Ig variable (V) and Ig constant (C) domain sequences. Recent reports have described splice variant forms of B7 proteins which occur in vivo and are of unknown function. Here we describe soluble recombinant forms of B7-1 and B7-2 containing either both of the Ig-like extracellular domains or the individual IgV or IgC domains coupled to an Ig Fc tail. Soluble B7-1 and B7-2 bind to CD28 and CTLA-4, and effectively cc-stimulate T lymphocytes resulting in their proliferation and the secretion of cytokines. Furthermore, the IgV domain of B7-2 binds CD28 and CTLA-4, competes with B7-1 and B7-2 for binding to these receptors, and co-stimulates T lymphocytes. Cross-linked soluble B7-2v was the most potent co-stimulatory molecule tested and was active at a concentration similar to 100-fold lower than cross-linked soluble B7-1 or B7-2 proteins. When bound to tosyl-activated beads, B7-2v was capable of sustaining multiple rounds of T cell expansion. These data complement the description of naturally occuring variants to suggest that T cell co-stimulation in vivo may be regulated by soluble or truncated forms of B7 proteins. C1 REPLIGEN CORP,DEPT MOL BIOL,CAMBRIDGE,MA 02139. REPLIGEN CORP,DEPT IMMUNOL,CAMBRIDGE,MA 02139. USN,MED RES INST,IMMUNE CELL BIOL PROGRAM,BETHESDA,MD 20814. HARVARD UNIV,SCH MED,DANA FARBER CANC INST,DIV HEMATOL MALIGNANCIES,BOSTON,MA 02115. NR 37 TC 35 Z9 35 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD, ENGLAND OX2 6DP SN 0953-8178 J9 INT IMMUNOL JI Int. Immunol. PD JUN PY 1997 VL 9 IS 6 BP 805 EP 813 DI 10.1093/intimm/9.6.805 PG 9 WC Immunology SC Immunology GA XE891 UT WOS:A1997XE89100001 PM 9199963 ER PT J AU Pitcher, GK Kavarnos, GJ AF Pitcher, GK Kavarnos, GJ TI A test assembly for hydrogen production by the hydrolysis of solid lithium hydride SO INTERNATIONAL JOURNAL OF HYDROGEN ENERGY LA English DT Article AB The design of an experimental test vessel to generate hydrogen gas from the hydrolysis of lithium hydride is described. The test vessel consists of a reaction chamber equipped with a demountable sample holder to retain a pellet of solid lithium hydride. A solenoid-driven, diaphragm-type metering pump delivers water at rates from 1 to 10 ml/min. As hydrogen gas and LiOH evolve, these products pass into a chamber that is connected to a collecting bottle. Temperature and pressure are monitored during reaction and are used to identify the behavior and controllability of the reaction before scale-up as a quiet, long-endurance propulsion system for unmanned undersea vehicles. A major finding is that the hydrogen generation rate is controlled to a greater extent by the rate of water supply rather than surface area of the lithium hydride pellet, reaction pressure, and water salinity. RP Pitcher, GK (reprint author), USN,UNDERSEA WARFARE CTR DIV,WEAPONS & TECHNOL & UNDERSEA SYST DEPT,NEWPORT,RI 02841, USA. NR 6 TC 8 Z9 8 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0360-3199 J9 INT J HYDROGEN ENERG JI Int. J. Hydrog. Energy PD JUN PY 1997 VL 22 IS 6 BP 575 EP 579 DI 10.1016/S0360-3199(96)00190-5 PG 5 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA WX517 UT WOS:A1997WX51700005 ER PT J AU Sarkar, N Yun, XP Kumar, V AF Sarkar, N Yun, XP Kumar, V TI Control of contact interactions with acatastatic nonholonomic constraints SO INTERNATIONAL JOURNAL OF ROBOTICS RESEARCH LA English DT Article ID MULTIFINGERED HANDS; RIGID BODIES; MOTION; MANIPULATION; KINEMATICS; SYSTEMS AB A robot arm performs many tasks by interacting with objects or other robots in the environment. It is important for the robot arm to be able to exhibit controlled interactions with the objects and other robots. The contact motion between the robot arm and an object can be rolling, sliding, or separation. In this article we address the problem of maintaining rolling contact between the robot arm and an external moving object. We assume that a nominal model of the motion of the moving object is available. The dynamic system that characterizes the motion of the robot arm and the moving object in this case is acatastatic and nonholonomic. We have designed a nonlinear feedback for the control of such a system that successfully maintains rolling contact. Simulation results are presented to demonstrate the effectiveness of the system. C1 USN, POSTGRAD SCH, DEPT ELECT & COMP ENGN, MONTEREY, CA 93943 USA. UNIV PENN, GRASP LAB, PHILADELPHIA, PA 19104 USA. RP UNIV HAWAII MANOA, DEPT MECH ENGN, HONOLULU, HI 96822 USA. NR 31 TC 12 Z9 12 U1 0 U2 1 PU SAGE PUBLICATIONS LTD PI LONDON PA 1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLAND SN 0278-3649 EI 1741-3176 J9 INT J ROBOT RES JI Int. J. Robot. Res. PD JUN PY 1997 VL 16 IS 3 BP 357 EP 374 DI 10.1177/027836499701600306 PG 18 WC Robotics SC Robotics GA XG718 UT WOS:A1997XG71800006 ER PT J AU Rowe, NC AF Rowe, NC TI Obtaining optimal mobile-robot paths with nonsmooth anisotropic cost functions using qualitative-state reasoning SO INTERNATIONAL JOURNAL OF ROBOTICS RESEARCH LA English DT Article ID FRICTION; TERRAIN AB Realistic path-planning problems frequently show anisotropism, dependency of traversal cost or feasibility on the traversal heading. Gravity, friction, visibility, and safety are often anisotropic for mobile robots. Anisotropism often differs qualitatively with heading, as when a vehicle has insufficient power to go uphill or must brake to avoid accelerating downhill. Modeling qualitative distinctions requires discontinuities in either the cost-per-traversal-distance function or its derivatives, preventing direct application of most results of the calculus of variations. We present a new approach to optimal anisotropic path planning that first identifies qualitative states and permissible transitions between them. If the qualitative states are chosen appropriately, our approach replaces an optimization problem with such discontinuities by a set of subproblems without discontinuities, subproblems for which optimization is likely to be faster and less troublesome. Then the state space in the near neighborhood of any particular state can be partitioned into ''behavioral regions'' representing states optimally reachable by single qualitative ''behaviors,'' sequences of qualitative states in a finite-state diagram. Simplification of inequalities and other methods can identify the behavioral regions. Our ideas solve problems that are not easily solvable any other way, especially problems with what we define as ''turn-hostile'' anisotropism. We illustrate our methods on two examples, navigation on an arbitrarily curved surface with gravity and friction effects (for which we show much better performance than a previously published program 22 times longer), and flight of a simple missile. RP USN, POSTGRAD SCH, DEPT COMP SCI, MONTEREY, CA 93943 USA. NR 22 TC 15 Z9 15 U1 0 U2 0 PU SAGE PUBLICATIONS LTD PI LONDON PA 1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLAND SN 0278-3649 EI 1741-3176 J9 INT J ROBOT RES JI Int. J. Robot. Res. PD JUN PY 1997 VL 16 IS 3 BP 375 EP 399 DI 10.1177/027836499701600307 PG 25 WC Robotics SC Robotics GA XG718 UT WOS:A1997XG71800007 ER PT J AU Layne, C AF Layne, C TI From preponderance to offshore balancing - America's future grand strategy SO INTERNATIONAL SECURITY LA English DT Review ID COLD-WAR; WORLD; EUROPE; CHINA; POWER RP Layne, C (reprint author), USN,POSTGRAD SCH,MONTEREY,CA 93940, USA. NR 145 TC 101 Z9 102 U1 5 U2 19 PU M I T PRESS PI CAMBRIDGE PA FIVE CAMBRIDGE CENTER, CAMBRIDGE, MA 02142 SN 0162-2889 J9 INT SECURITY JI Int. Secur. PD SUM PY 1997 VL 22 IS 1 BP 86 EP 124 DI 10.2307/2539331 PG 39 WC International Relations SC International Relations GA XN615 UT WOS:A1997XN61500009 ER PT J AU Borden, B AF Borden, B TI Some issues in inverse synthetic aperture radar image reconstruction SO INVERSE PROBLEMS LA English DT Article ID ISAR; SCATTERING; CAVITY AB One-dimensional radar target recognition schemes are based upon so-called 'range profiles' and contain little or no cross-range target information. This limitation often restricts the usefulness of range-only methods in problems of target identification and target detection-in-clutter. Consequently, cross-range algorithms are usually required for these more demanding tasks. Because the ratio of wavelength to physical aperture is so much greater than it is for optical instruments of comparable dimensions, radar 'imaging' methods usually attempt to artificially increase the effective aperture of the data acquisition system by employing SAR or ISAR techniques. Unfortunately, there are a host of problems associated with practical implementations of these SAR/ISAR techniques and the quality of the reconstructed image-as well as our ability to interpret it-can be seriously compromised. We present a brief overview of the ISAR techniques relevant to the problem of target recognition and pay special attention to scattering model limitations, sources of reconstruction error, and some current efforts to address these problems. RP Borden, B (reprint author), USN,CTR WEAP,WEAP DIV,RES DEPT,CHINA LAKE,CA 93555, USA. NR 56 TC 13 Z9 13 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL, ENGLAND BS1 6BE SN 0266-5611 J9 INVERSE PROBL JI Inverse Probl. PD JUN PY 1997 VL 13 IS 3 BP 571 EP 584 DI 10.1088/0266-5611/13/3/004 PG 14 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA XE246 UT WOS:A1997XE24600004 ER PT J AU Roy, DNG Couchman, L Warner, J AF Roy, DNG Couchman, L Warner, J TI Scattering and inverse scattering of sound-hard obstacles via shape deformation SO INVERSE PROBLEMS LA English DT Article ID DOMAIN AB Direct and inverse scattering of plane acoustic waves from sound-hard obstacles are discussed. The direct problem is solved via the application of the Pade approximation. It is shown that this involves solving only certain algebraic recursion relations and requires neither Green's functions nor integral representations of the field. The shape of the scatterer is assumed to be a superposition of a deformation (allowed to be finite) over an underlying simple geometry. It is demonstrated that such a decomposition allows the scattered field to be obtained as solutions of classical Neumann problems in domains exterior to the underlying simple shape instead of the actual deformed contour. This introduces simplifications in the implementation of a Gauss-Newton type inversion procedure which was used in this study. Some inversions of two-dimensional scatterers are presented. C1 USN,RES LAB,WASHINGTON,DC 20375. RP Roy, DNG (reprint author), SFA INC,1401 MCCORMICK DR,LANDOVER,MD 20785, USA. NR 17 TC 12 Z9 12 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL, ENGLAND BS1 6BE SN 0266-5611 J9 INVERSE PROBL JI Inverse Probl. PD JUN PY 1997 VL 13 IS 3 BP 585 EP 606 DI 10.1088/0266-5611/13/3/005 PG 22 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA XE246 UT WOS:A1997XE24600005 ER PT J AU Hirsch, RL Kulcinski, G Shanny, R AF Hirsch, RL Kulcinski, G Shanny, R TI Fusion research with a future SO ISSUES IN SCIENCE AND TECHNOLOGY LA English DT Article C1 UNIV WISCONSIN,FUS TECHNOL INST,MADISON,WI 53706. USN,RES LAB,PLASMA PHYS PROGRAM,WASHINGTON,DC 20375. RP Hirsch, RL (reprint author), NATL RES COUNCIL,BOARD ENERGY & ENVIRONM SYST,WASHINGTON,DC 20418, USA. NR 3 TC 0 Z9 0 U1 0 U2 1 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 SN 0748-5492 J9 ISSUES SCI TECHNOL JI Issues Sci. Technol. PD SUM PY 1997 VL 13 IS 4 BP 60 EP 64 PG 5 WC Engineering, Multidisciplinary; Engineering, Industrial; Multidisciplinary Sciences; Social Issues SC Engineering; Science & Technology - Other Topics; Social Issues GA XK379 UT WOS:A1997XK37900034 ER PT J AU Thompson, PE Silvestre, C Jernigan, G Hobart, K Simons, DS Gregg, MR AF Thompson, PE Silvestre, C Jernigan, G Hobart, K Simons, DS Gregg, MR TI Effect of Ge on the segregation of B in Si(100) and Si(110) SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MOLECULAR-BEAM EPITAXY; SB SURFACE SEGREGATION; LOW-TEMPERATURE; SI; SILICON AB The segregation of B from Si1-xGex quantum wells grown using molecular beam epitaxy on Si(100) and Si(110) was investigated using secondary ion mass spectrometry. When a 3 nm B doping slab (n=10(19)/cm(3)) was placed in the center of a 6 nm Si1-xGex quantum well, the B profiles had two distinct exponential decay lengths, Delta(SiGe), the Ge-controlled B decay length and Delta(Si), the B decay length normally measured in Si. Delta(SiGe) was the same for Si(100) and Si(110) and independent of Ge concentration in the well for 0.1 less than or equal to x less than or equal to 0.5. As the Ge concentration was increased in the well, the location of the transition point, from Delta(SiGe) to Delta(Si), which was always found far outside of the SiGe quantum well, increased in distance from the center of the well. C1 NIST,GAITHERSBURG,MD 20899. USAF,INST TECHNOL,WRIGHT PATTERSON AFB,OH 45433. RP Thompson, PE (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 14 TC 1 Z9 1 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 1 PY 1997 VL 81 IS 11 BP 7317 EP 7319 DI 10.1063/1.365359 PG 3 WC Physics, Applied SC Physics GA XC348 UT WOS:A1997XC34800030 ER PT J AU Gruber, JB Zandi, B Seltzer, MD AF Gruber, JB Zandi, B Seltzer, MD TI Spectra and energy levels of trivalent holmium in strontium fluorapatite SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID YTTRIUM-ALUMINUM-GARNET AB Polarized absorption and fluorescence spectra are reported for Ho3+ (4f(10)) ions incorporated into single crystals of strontium fluorapatite, Sr-5(PO4)(3)F, also known as SFAP. Site-selective excitation experiments indicate that, to within instrumental resolution, the Ho3+ ions occupy similar lattice sites having C-s symmetry. Spectra were obtained between 1940 and 400 nm at temperatures from 4 K to room temperature on crystals having the hexagonal structure [P6(3)/m(C-6h(2))]. Individual energy (Stark) levels for the fourteen lowest-energy multiplet manifolds of Ho3+ (4f(10)) were analyzed in detail. These manifolds include the I-5(8) (ground state), the remaining I-5(J) manifolds, F-5(J), S-5(2), K-3(8)(2), (5)G(6), and the (3)G(5)(2) manifolds. A Hamiltonian consisting of Coulombic, spin-orbit, and crystal-field terms was diagonalized over these manifolds in an LSJM(J) bas;is set, which includes 146 crystal-quantum states, labeled either Gamma(1) or Gamma(2), appropriate to the crystal-field symmetry of C-s. By varying the crystal-field parameters, B-nm, and the centroid for each manifold, we obtained agreement between 101 experimental and calculated Stark levels with a rms deviation of 9 cm(-1). An additional 15 Stark levels, not included in the original analyses, are predicted to within the rms deviation. The predicted symmetry label of each Stark level agrees with the experimental assignment based on the analysis of the polarized spectra. (C) 1997 American Institute of Physics. C1 USA,RES LAB,SENSORS & ELECTRON DEVICES DIRECTORATE,ADELPHI,MD 20783. USN,AIR WARFARE CTR,DIV WEAPONS,RES & TECHNOL GRP,CHINA LAKE,CA 93555. RP Gruber, JB (reprint author), SAN JOSE STATE UNIV,DEPT PHYS,SAN JOSE,CA 95192, USA. NR 26 TC 8 Z9 8 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 1 PY 1997 VL 81 IS 11 BP 7506 EP 7513 DI 10.1063/1.365292 PG 8 WC Physics, Applied SC Physics GA XC348 UT WOS:A1997XC34800058 ER PT J AU Meyer, JR Vurgaftman, I Hoffman, CA AF Meyer, JR Vurgaftman, I Hoffman, CA TI Intersubband all-optical limiter based on thermally induced intervalley transfer SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID QUANTUM-WELLS; INFRARED PHOTODETECTORS; ABSORPTION; SUPERLATTICES; MODULATION; TRANSITIONS AB We propose an all-optical limiter based on the thermally induced intervalley transfer of electrons from Gamma-valley states with forbidden normal-incidence intersubband interactions to L-valley states which absorb strongly. Detailed modeling of the device performance in the short-pulse regime (less than or equal to 100 ns) yields that the output intensity for a limiter with only 10% insertion loss at low excitation levels will remain clamped over a dynamic range of 25-40. RP Meyer, JR (reprint author), USN,RES LAB,CODE 5610,WASHINGTON,DC 20375, USA. NR 19 TC 4 Z9 4 U1 2 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 1 PY 1997 VL 81 IS 11 BP 7662 EP 7665 DI 10.1063/1.365344 PG 4 WC Physics, Applied SC Physics GA XC348 UT WOS:A1997XC34800082 ER PT J AU Rudolph, AS Sulpizio, A Hieble, P MacDonald, V Chavez, M Feuerstein, G AF Rudolph, AS Sulpizio, A Hieble, P MacDonald, V Chavez, M Feuerstein, G TI Liposome encapsulation attenuates hemoglobin-induced vasoconstriction in rabbit arterial segments SO JOURNAL OF APPLIED PHYSIOLOGY LA English DT Article DE nitric oxide; blood substitute ID CROSS-LINKED HEMOGLOBIN; RECOMBINANT HUMAN HEMOGLOBIN; STROMA-FREE HEMOGLOBIN; NITRIC-OXIDE; EXCHANGE-TRANSFUSION; BIOLOGICAL RESPONSES; RESUSCITATIVE FLUID; BLOOD SUBSTITUTE; SALINE SOLUTION; EAR ARTERY AB Free hemoglobin (Hb) induces a potent vasoconstrictor response that may limit its therapeutic application as a red blood cell replacement. We have investigated whether encapsulation of stroma-free Hb (SFHb) or cross-linked HI, (alpha alpha-Hb) in Liposomes modulates Hb vasoactivity in isolated blood vessels. Relaxation of rabbit thoracic vessels was measured before and after exposure to acellular SFHb. alpha alpha-Hb, and liposome-encapsulated SFHb or alpha alpha-Hb. SFHb and alpha alpha-Hb caused significant inhibition of carbachol-induced relaxation at 0.5 mg/dl, whereas encapsulation inhibited vessel relaxation at 30- to 60-fold higher Hb concentrations. The contractile response of rabbit ear arterial segments to electrical stimulation in the presence of acellular alpha alpha-Hb resulted in a 150% increase (EC150) in contractile amplitude at 0.23 mg/dl: whereas the EC150 for encapsulated alpha alpha-Hb was 13.7 mg/dl. Mechanistic studies of the vasoconstrictor activity of Hb demonstrated that acellular alpha alpha-Hb had no effect on norepinephrine release in the rabbit ear artery. In addition, neither acellular nor encapsulated alpha alpha-Hb preparations inhibited endothelial nitric oxide (NO) synthase activity isolated from bovine pulmonary artery. However, inhibition of vessel relaxation by acellular or encapsulated cra-Hb was reversed by the NO donor S-nitrosylpenacillamine, implicating Hb-NO binding as a possible mechanism for the vasoconstrictor response. Ln vitro stopped-flow kinetic studies of Hb-NO binding showed similar rates of reaction for conversion of oxyhemoglobin to methemoglobin (metHb; <2 ms), followed by rapid conversion of metHb to NO-Hb, (300 ms) for both acellular and encapsulated aa-Hb, demonstrating that liposome encapsulation does not retard NO-Hb binding. The attenuated vasoactivity of encapsulated Kb may, therefore, result from the limited access of encapsulated Hb to NO imposed by the physical size of the liposome and reduced penetration of Hb across the vascular endothelium. C1 SMITHKLINE BEECHAM,DEPT CARDIOVASC PHARMACOL,KING OF PRUSSIA,PA 19406. WALTER REED ARMY INST RES,BLOOD RES DETACHMENT,WASHINGTON,DC 20307. RP Rudolph, AS (reprint author), USN,RES LAB,CTR BIOMOL SCI & ENGN,CODE 6910,WASHINGTON,DC 20375, USA. NR 56 TC 39 Z9 40 U1 0 U2 1 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 SN 8750-7587 J9 J APPL PHYSIOL JI J. Appl. Physiol. PD JUN PY 1997 VL 82 IS 6 BP 1826 EP 1835 PG 10 WC Physiology; Sport Sciences SC Physiology; Sport Sciences GA XD265 UT WOS:A1997XD26500017 PM 9173947 ER PT J AU Nystuen, JA Selsor, HD AF Nystuen, JA Selsor, HD TI Weather classification using passive acoustic drifters SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID OCEANIC WINDS; AMBIENT SOUND; NOISE; RAINFALL; PRECIPITATION AB Weather observations are needed in remote oceanic regions to support numerical weather forecast models, to provide surface truth for satellite sensors, and to help understand global weather patterns. An acoustic mini-drifting buoy using no moving parts has been designed to meet operational naval demands for real-time monitoring of upper-ocean air-sea interface processes. This buoy is an air-deployable, standard sonobuoy-sized buoy that uses an Argos satellite link to transmit data to users. Interpretation of the ambient sound field allows classification of weather into five categories: wind, wind and drizzle, rain, high seas, and shipping contaminated. Quantitative estimates of wind speed are shown to be in agreement with the Special Sensor Microwave/Imager satellite sensor. Rainfall detection is confirmed and rainfall rate quantified using an acoustic rainfall-rate algorithm. Atmospheric pressure, air and sea temperature, and ambient sound levels are measured directly. C1 USN,RES LAB,TACT OCEANOG WARFARE SUPPORT PROGRAM OFF,BAY ST LOUIS,MS 39529. RP Nystuen, JA (reprint author), UNIV WASHINGTON,APPL PHYS LAB,1013 NE 40TH ST,SEATTLE,WA 98105, USA. NR 26 TC 26 Z9 27 U1 1 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD JUN PY 1997 VL 14 IS 3 BP 656 EP 666 DI 10.1175/1520-0426(1997)014<0656:WCUPAD>2.0.CO;2 PN 2 PG 11 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA XC595 UT WOS:A1997XC59500007 ER PT J AU Chu, PC Fan, CW Ehret, LL AF Chu, PC Fan, CW Ehret, LL TI Determination of open boundary conditions with an optimization method SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID MODEL AB The optimization method proposed in this paper is for determining open boundary conditions from interior observations. Unknown open boundary conditions are represented by an open boundary parameter vector (B), while known interior observational values are used to form an observation vector (O). For a hypothetical B* (generally taken as the zero vector for the first time step and as the optimally determined B al the previous time step afterward), the numerical ocean model is integrated to obtain solutions (S*) at interior observation points. The root-mean-square difference between S* and O might not be minimal. The authors change B* with different increments delta B. Optimization is used to get the best B by minimizing the error between O and S. The proposed optimization method can be easily incorporated into any ocean models, whether linear or nonlinear, reversible or irreversible, etc. Applying this method to a primitive equation model with turbulent mixing processes such as the Princeton Ocean Model (POM), an important procedure is to smooth the open boundary parameter vector. If smoothing is not used, POM can only be integrated within a finite period (45 days in this case). If smoothing is used, the model is computationally stable. Furthermore, this optimization method performed well when random noise was added to the ''observational'' points. This indicates that realtime data can be used to inverse the unknown open boundary values. RP Chu, PC (reprint author), USN,POSTGRAD SCH,DEPT OCEANOG,CODE OC CU,MONTEREY,CA 93943, USA. NR 11 TC 12 Z9 12 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD JUN PY 1997 VL 14 IS 3 BP 723 EP 734 DI 10.1175/1520-0426(1997)014<0723:DOOBCW>2.0.CO;2 PN 2 PG 12 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA XC595 UT WOS:A1997XC59500013 ER PT J AU Dawson, TH AF Dawson, TH TI Group structure in random seas SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID WAVE GROUPS; WATER AB Markov theory for statistics of runs of high waves in a random sea is extended to include the special case where runs consist of two or more high waves, that is, for the case of wave groups. Expressions are derived for the average number of waves forming the groups, for the relative number of groups expected, and for the average number of waves between the beginnings of groups. Theoretical results are shown to be in good agreement with data determined from laboratory and computer simulations and from field measurements. RP Dawson, TH (reprint author), USN ACAD,OCEAN ENGN PROGRAM,590 HOLLOWAY RD,ANNAPOLIS,MD 21402, USA. NR 12 TC 5 Z9 6 U1 1 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD JUN PY 1997 VL 14 IS 3 BP 741 EP 747 DI 10.1175/1520-0426(1997)014<0741:GSIRS>2.0.CO;2 PN 2 PG 7 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA XC595 UT WOS:A1997XC59500015 ER PT J AU Guerry, P PerezCasal, J Yao, RJ McVeigh, A Trust, TJ AF Guerry, P PerezCasal, J Yao, RJ McVeigh, A Trust, TJ TI A genetic locus involved in iron utilization unique to some Campylobacter strains SO JOURNAL OF BACTERIOLOGY LA English DT Article ID INFLUENZAE TYPE-B; OUTER-MEMBRANE PROTEIN; VIBRIO-CHOLERAE; ESCHERICHIA-COLI; FLAGELLIN GENES; MOLECULAR CHARACTERIZATION; YERSINIA-ENTEROCOLITICA; CYTOPLASMIC MEMBRANE; HEMOLYSIN PRODUCTION; ANTIGENIC VARIATION AB Two genes involved in iron utilization in Campylobacter coli VC167 T1 have been characterized. The cfrA gene encodes a protein with a predicted M-r of 77,653 which, after processing of the leader sequence, has a predicted M-r of 75,635, This protein has significant sequence identity to siderophore receptors of several bacteria, and site-specific mutants defective in cfrA do not synthesize one of two major iron-repressible outer membrane proteins. An adjacent gene encodes a TonB-like protein; a mutant in this gene lost the ability to utilize hemin, ferrichrome, and enterochelin as iron sources. The cfrA and tonB genes of VC167 T1 hybridized to all strains of C. coli and most strains of C. jejuni examined but did not hybridize to several other strains of C. jejuni, suggesting that the thermophilic campylobacters can be separated into two categories based on the presence of these two iron utilization genes. C1 USN,MED RES INST,ENTER DIS BRANCH,BETHESDA,MD 20889. UNIV VICTORIA,DEPT MICROBIOL & BIOCHEM,VICTORIA,BC V8W 3P6,CANADA. NR 58 TC 28 Z9 29 U1 0 U2 3 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 SN 0021-9193 J9 J BACTERIOL JI J. Bacteriol. PD JUN PY 1997 VL 179 IS 12 BP 3997 EP 4002 PG 6 WC Microbiology SC Microbiology GA XE300 UT WOS:A1997XE30000023 PM 9190817 ER PT J AU Rosenfeld, P AF Rosenfeld, P TI Impression management, fairness, and the employment interview SO JOURNAL OF BUSINESS ETHICS LA English DT Article ID SELECTION INTERVIEW; SELF-PRESENTATION; APPLICANT; DIVERSITY; TACTICS AB This paper contends that impression management is not inherently a threat to fairness in employment interviews. Rather, regarding impression management as unfair is based on an outdated, narrow view of impression management as conscious, manipulative, and deceptive. A broader, expansive model of impression management is described which sees these behaviors as falling on a continuum from deceptive and manipulative on the one hand, to accurate, positive and beneficial on the other. While organizations may want to eliminate or discount the negative aspect of the impression management continuum, the ability to positively ''sell'' oneself is often a desirable attribute both in the employment interview and in later on-the-job settings. This expansive view of impression management contends that organizations can make employment interviews more fair by: viewing impression management as a skill and not a deficit, training interviewers to be wary of manipulative and deceptive impression management, reducing the ambiguity and uncertainty of interview settings and increasing the verifiability of candidate responses by focusing the interview on a candidate's long-term identities and accomplishments rather than their short-term, spur-of-the-moment attempts to please the interviewer. RP Rosenfeld, P (reprint author), USN,CTR PERSONNEL RES & DEV,CODE 12,53335 RYNE RD,SAN DIEGO,CA 92152, USA. NR 25 TC 18 Z9 21 U1 1 U2 6 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0167-4544 J9 J BUS ETHICS JI J. Bus. Ethics PD JUN PY 1997 VL 16 IS 8 BP 801 EP 808 DI 10.1023/A:1017972627516 PG 8 WC Business; Ethics SC Business & Economics; Social Sciences - Other Topics GA XE724 UT WOS:A1997XE72400004 ER PT J AU Hill, EA Yesinowski, JP AF Hill, EA Yesinowski, JP TI A slow-turning method for measuring large anisotropic interactions in inhomogeneously broadened nuclear magnetic resonance spectra SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID NMR-SPECTROSCOPY; FOURIER-TRANSFORM; SOLIDS; N-14; KNO3 AB A new NMR method is proposed for measuring anisotropic spin-Hamiltonian parameters, STEAMER (slow turning echo amplitude modulation and echo reduction). It involves slow turning of a powdered sample about an axis perpendicular to the external magnetic field. We have theoretically analyzed and experimentally demonstrated this technique for the specific case of an axially symmetric second-rank tensor interaction. The method relies upon a slow continuous rotation of the sample that changes the orientation of the principal-axis systems of interaction tensors with respect to the external magnetic field and renders the spin Hamiltonian time dependent. As a consequence a conventional Hahn spin-echo pulse sequence yields imperfect refocusing and altered echo amplitudes. Two principal advantages of STEAMER are that only a small portion of the entire powder pattern need be observed at a single frequency and that anisotropic interactions can be distinguished from distributions of isotropic interactions. The N-14 (I=1) selectively excited pi/2-pi spin-echo NMR signal in KNO3 provides a good test case for the effects of slow turning (rotation at 1 rpm) since it has a first-order quadrupole interaction from a N-14 nuclear quadrupole coupling constant (NQCC) of 0.75 MHz and a small asymmetry parameter (0.022), Theoretical simulations of the echo amplitude as a function of the pulse interval for an axially symmetric second-rank tensor agree well with the experimental results at a chosen frequency, These numerical simulations are compared to an analytical approximation derived in terms of the zeroth-order Bessel function. In addition, a simple graphical method for obtaining NQCC values from STEAMER data is developed. Other aspects and possible extensions of the STEAMER experiment are discussed. C1 USN,RES LAB,WASHINGTON,DC 20375. NR 18 TC 18 Z9 18 U1 0 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUN 1 PY 1997 VL 106 IS 21 BP 8650 EP 8659 DI 10.1063/1.473926 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA XA478 UT WOS:A1997XA47800002 ER PT J AU White, DA Taylor, MJ Butters, N Mack, C Salmon, DP Peavy, G Ryan, L Heaton, RK Atkinson, JH Chandler, JL Grant, I Kelly, M Wallace, MR McCutchan, JA Spector, SA Thal, L Hesselink, J Jernigan, T Masliah, E Wiley, CA Abramson, I Dupont, R Patterson, T Zisook, S Jeste, D Sieburg, H Weinrich, JD AF White, DA Taylor, MJ Butters, N Mack, C Salmon, DP Peavy, G Ryan, L Heaton, RK Atkinson, JH Chandler, JL Grant, I Kelly, M Wallace, MR McCutchan, JA Spector, SA Thal, L Hesselink, J Jernigan, T Masliah, E Wiley, CA Abramson, I Dupont, R Patterson, T Zisook, S Jeste, D Sieburg, H Weinrich, JD TI Memory for verbal information in individuals with HIV-associated dementia complex SO JOURNAL OF CLINICAL AND EXPERIMENTAL NEUROPSYCHOLOGY LA English DT Article ID SUBCORTICAL DYSFUNCTION; HUNTINGTONS-DISEASE; AIDS; INFECTION; PERFORMANCE; BRAIN; RECOGNITION; VALIDATION; PREVALENCE; RECALL AB Patterns of memory performance were examined for 9 participants with HIV-associated dementia (HAD), 15 HIV-seropositive participants without dementia, and 15 HIV-seronegative controls. Episodic and semantic memory were assessed using the California Verbal Learning Test, the Boston Naming Test, and Verbal Fluency tests. The HAD group showed deficits in episodic memory, with relative sparing of semantic memory. In addition, results suggest a retrieval deficit in HAD rather than a deficit in retention of information. This pattern is consistent with the presence of a subcortical dementing process and supports findings from previous neuropathological, neuroimaging, and neuropsychological studies suggesting that subcortical brain dysfunction is frequently associated with HIV disease (e.g., Navia, Jordan, & Price, 1986). C1 UNIV CALIF SAN DIEGO,DEPT PSYCHIAT,LA JOLLA,CA 92093. DEPT VET AFFAIRS MED CTR,SAN DIEGO,CA. USN,MED CTR,SAN DIEGO,CA 92152. NAVAL HOSP,SAN DIEGO,CA. RP White, DA (reprint author), WASHINGTON UNIV,DEPT PSYCHOL,BOX 1125,1 BROOKINGS DR,ST LOUIS,MO 63130, USA. FU NIMH NIH HHS [5 P50 MH45294] NR 40 TC 31 Z9 33 U1 1 U2 2 PU SWETS ZEITLINGER PUBLISHERS PI LISSE PA P O BOX 825, 2160 SZ LISSE, NETHERLANDS SN 1380-3395 J9 J CLIN EXP NEUROPSYC JI J. Clin. Exp. Neuropsychol. PD JUN PY 1997 VL 19 IS 3 BP 357 EP 366 DI 10.1080/01688639708403864 PG 10 WC Psychology, Clinical; Clinical Neurology; Psychology SC Psychology; Neurosciences & Neurology GA XM028 UT WOS:A1997XM02800004 PM 9268810 ER PT J AU Wax, JR Henderson, E AF Wax, JR Henderson, E TI Effect of fetal movement on the amniotic fluid index in diamniotic twin gestations SO JOURNAL OF CLINICAL ULTRASOUND LA English DT Article DE amniotic fluid index; twin pregnancy; amniotic fluid volume; fetal testing ID 4-QUADRANT ASSESSMENT; VOLUME; INTEROBSERVER; INTRAOBSERVER; PREGNANCIES AB Fetal movement changes the size and location of amniotic fluid pockets during measurement of the amniotic fluid index. In singleton gestations, the effect of redistributing the fixed intrauterine fluid volume on the amniotic fluid index is clinically insignificant. In this study, we tested the hypothesis that the index in twin pregnancies is unaffected by fetal movement. A single examiner prospectively determined the amniotic fluid index before and after three discrete episodes of movement by both fetuses of 82 diamniotic twin pregnancies referred for obstetric sonograms between 20 and 38 weeks' menstrual age. A reliable blinded examiner provided a second post-movement measurement as a control. Data were analyzed by the paired t-test. The mean change in the amniotic fluid index after fetal movement was 2.1 +/- 0.2 cm and 3.7 +/- 0.3 cm for post-movement determinations by the same and blinded examiners, respectively (p < .001). Interobserver variation was 3.5 cm. Intraobserver variation was 1.8 cm for the first examiner and 2.2 cm for the second examiner. Therefore, interobserver and intraobserver Variation can account for the observed change in the amniotic fluid index following movement of both diamniotic twins. (C) 1997 John Wiley & Sons, Inc. RP Wax, JR (reprint author), USN,MED CTR,DEPT OBSTET & GYNECOL,DIV MATERNAL FETAL MED,PORTSMOUTH,VA 23708, USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0091-2751 J9 J CLIN ULTRASOUND JI J. Clin. Ultrasound PD JUN PY 1997 VL 25 IS 5 BP 255 EP 257 PG 3 WC Acoustics; Radiology, Nuclear Medicine & Medical Imaging SC Acoustics; Radiology, Nuclear Medicine & Medical Imaging GA WW922 UT WOS:A1997WW92200006 PM 9314107 ER PT J AU Lee, D Nagem, RJ Resasco, DC AF Lee, D Nagem, RJ Resasco, DC TI Numerical computations of elastic wave equations SO JOURNAL OF COMPUTATIONAL ACOUSTICS LA English DT Article ID PARABOLIC EQUATION; PROPAGATION; SOLIDS; OCEAN; MEDIA AB An improved numerical scheme is introduced for solving a set of three-dimensional parabolic elastic wave equations. The new scheme is based on the combination of an ordinary differential equation method and a finite difference scheme. A stability analysis of the numerical method is presented along with a numerical example in which computational accuracy is verified by comparison with an exact three-dimensional analytic solution. C1 YALE UNIV,NEW HAVEN,CT. BOSTON UNIV,BOSTON,MA 02215. RP Lee, D (reprint author), USN,UNDERSEA WARFARE CTR,NEW LONDON,CT 06320, USA. NR 21 TC 3 Z9 3 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 9128, SINGAPORE SN 0218-396X J9 J COMPUT ACOUST JI J. Comput. Acoust. PD JUN PY 1997 VL 5 IS 2 BP 157 EP 176 DI 10.1142/S0218396X97000101 PG 20 WC Acoustics; Mathematics, Interdisciplinary Applications SC Acoustics; Mathematics GA XM025 UT WOS:A1997XM02500002 ER PT J AU Marchette, DJ Wegman, EJ AF Marchette, DJ Wegman, EJ TI The filtered mode tree SO JOURNAL OF COMPUTATIONAL AND GRAPHICAL STATISTICS LA English DT Article DE bump hunting; filtered kernel density estimation; graphical methods; kernel density estimation; mode estimation; multimodality AB The mode tree is a useful tool for visualizing the modal structure of a density. Locations of modes of the density are plotted as a function of the bandwidth used in the kernel estimate of the density. Because the mode tree uses a single bandwidth in the kernel estimator, it exhibits all the drawbacks that a single bandwidth kernel estimator has, particularly for densities with large tails or differences in the scales of the modes. A modification is presented that uses the filtered kernel estimator, a version of the kernel estimator using a small number of bandwidths. The two mode trees are compared on some synthetic data, and on a data set from DNA flow cytometry. C1 GEORGE MASON UNIV,CTR COMPUTAT STAT,FAIRFAX,VA 22030. RP Marchette, DJ (reprint author), USN,CTR SURFACE WEAP,CODE B10,DAHLGREN,VA 22448, USA. NR 11 TC 7 Z9 7 U1 0 U2 0 PU AMER STATISTICAL ASSOC PI ALEXANDRIA PA 1429 DUKE ST, ALEXANDRIA, VA 22314 SN 1061-8600 J9 J COMPUT GRAPH STAT JI J. Comput. Graph. Stat. PD JUN PY 1997 VL 6 IS 2 BP 143 EP 159 PG 17 WC Statistics & Probability SC Mathematics GA XF771 UT WOS:A1997XF77100001 ER PT J AU Binbasioglu, M Bui, T Ma, PC AF Binbasioglu, M Bui, T Ma, PC TI An action-resource language for negotiation support SO JOURNAL OF COMPUTER INFORMATION SYSTEMS LA English DT Article AB We view a group problem as a resource allocation among involved parties, and negotiation as the members' act to protect, or better yet, to gain additional resources for themselves. Group members gather together to achieve a common goal. They are also stakeholders seeking to defend their own interest as well. As such, negotiation can be seen as an effort of all parties seeking to exchange viewpoints, proposing offers and counter-offers with arguments, until a solution is found or a deadlock is considered unsolvable. This paper proposes an action-resource model to represent negotiation problems, and an argumentation language to support negotiation processes. The proposed action-resource language is illustrated by an actual negotiation - the softwood lumber negotiation between Canada and the United States. C1 USN,POSTGRAD SCH,MONTEREY,CA 93943. UNIV SCI & TECHNOL,HONG KONG,HONG KONG. RP Binbasioglu, M (reprint author), HOFSTRA UNIV,HEMPSTEAD,NY 11550, USA. NR 20 TC 3 Z9 3 U1 2 U2 2 PU INT ASSOC COMPUTER INFO SYSTEM PI STILLWATER PA OKLAHOMA ST UNIV COLLEGE OF BUSINESS, STILLWATER, OK 74078 SN 0887-4417 J9 J COMPUT INFORM SYST JI J. Comput. Inf. Syst. PD SUM PY 1997 VL 37 IS 4 BP 89 EP 96 PG 8 WC Computer Science, Information Systems SC Computer Science GA XM002 UT WOS:A1997XM00200015 ER PT J AU Mattson, MA Myers, TH RichardsBabb, M Meyer, JR AF Mattson, MA Myers, TH RichardsBabb, M Meyer, JR TI Evaluation of low-temperature interdiffusion coefficients in Hg-based superlattices by monitoring the E-1 reflectance peak SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 1996 US Workshop on The Physics and Chemistry of II-VI Materials CY OCT 22-24, 1996 CL LAS VEGAS, NV SP USA, Night Vis & Electro Opt Syst Directorate, USN, Naval Res Lab, USAF, Wright Labs, Amer Phys Soc, Minerals Met & Mat Soc DE HgTe-CdTe superlattice; k.p calculation; low temperature interdiffusion; molecular beam epitaxy ID CADMIUM TELLURIDE; INTER-DIFFUSION; CDTE; MERCURY; GROWTH AB We show that variations of the E-1 reflectance peak in Hg-based superlattices can be used to probe low-temperature interdiffusion by monitoring the shift of the E-1 peak wit time-over extended periods. Little evidence of interdiffusion was detected for a number of HgTe/CdTe and HgCdTe/CdTe superlattices stored at room temperature for approximately two years. Two HgTe/CdTe superlattices and one HgCdTe/CdTe superlattice were subsequently annealed in a dry nitrogen atmosphere at 100 degrees C for approximately six months, and then at 150 degrees C for 24 days. During these intervals, the superlattices were periodically removed from the anneal for reflectance measurements to assess the extent of the interdiffusion. Comparison of these results with calculations of superlattice bandgaps and interdiffusion profiles has led to an evaluation of the low temperature interdiffusion coefficients. These extend previous results to lower temperatures and confirm that the degradation of Hg-based superlattices devices due to thermal interdiffusion under normal processing, storage, and operating conditions should not be an issue of concern. C1 W VIRGINIA UNIV,DEPT CHEM,MORGANTOWN,WV 26506. USN,RES LAB,WASHINGTON,DC 20375. RP Mattson, MA (reprint author), W VIRGINIA UNIV,DEPT PHYS,MORGANTOWN,WV 26506, USA. RI Myers, Thomas/C-3769-2013 NR 25 TC 4 Z9 4 U1 0 U2 1 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD JUN PY 1997 VL 26 IS 6 BP 578 EP 583 DI 10.1007/s11664-997-0197-2 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA XF164 UT WOS:A1997XF16400019 ER PT J AU Park, JW Lee, J Moon, YM Choi, JB Hahn, MS Song, BK Hou, YB Kang, TW Yoo, KH Hoffman, CA Meyer, JR Jeoung, YT Kim, HK Kim, JM AF Park, JW Lee, J Moon, YM Choi, JB Hahn, MS Song, BK Hou, YB Kang, TW Yoo, KH Hoffman, CA Meyer, JR Jeoung, YT Kim, HK Kim, JM TI Inter-layer subband mixing in MBE-grown HgTe/CdTe superlattices SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 1996 US Workshop on The Physics and Chemistry of II-VI Materials CY OCT 22-24, 1996 CL LAS VEGAS, NV SP USA, Night Vis & Electro Opt Syst Directorate, USN, Naval Res Lab, USAF, Wright Labs, Amer Phys Soc, Minerals Met & Mat Soc DE effective 2D channels; HgTe/CdTe superlattice; inter-layer subband mixing; magnetotransport; quasi-3D growth-direction energy dispersion ID HGTE-CDTE SUPERLATTICES; MOLECULAR-BEAM EPITAXY; STIMULATED-EMISSION; QUANTUM; HG1-XCDXTE AB We report transport results for molecular beam epitaxially grown HgTe/CdTe superlattices (SLs) with CdTe barrier thickness of L-b systematically varied from 100 Angstrom down to 20 Angstrom, and demonstrate the increasing intersubband mixing between adjacent layers with decreasing L-b. Magnetotransport data measured at 1.5K and for B up to 10T show monotonously varying features with L-b, implying a dimensional change from 2D to quasi-3D. As L-b decreases, the quantum Hall plateaus become weaker and the number of effective 2D channels are decreased, which indicates increasing growth-direction energy dispersion. This enhanced interlayer subband coupling with decreasing L-b is further confirmed by the angle-dependence of SdH oscillations. For L-b = 20 Angstrom, all of 2D-related transport behavior are washed out. A quantitative analysis with calculated subband energy dispersion relations demonstrates the close interplay between superlattice barrier thickness and the strength of the intersubband mixing. These trans;sort results are directly related to successful control of the growth-axis carrier effective mass and will contribute to the development, of high-performance HgTe/CdTe SL-based IR photo-voltaic devices and lasers, in which tunneling noise due to diffusion currents can be considerably reduced. C1 DONGGUK UNIV, DEPT PHYS, SEOUL 100715, SOUTH KOREA. KOREA RES INST STAND & SCI, TAEJON 305763, SOUTH KOREA. USN, RES LAB, WASHINGTON, DC 20475 USA. AGCY DEF DEV, TAEJON 300600, SOUTH KOREA. RP Park, JW (reprint author), CHUNGBUK NATL UNIV, DEPT PHYS, CHONJU 360763, SOUTH KOREA. NR 8 TC 2 Z9 2 U1 1 U2 1 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD JUN PY 1997 VL 26 IS 6 BP 584 EP 587 DI 10.1007/s11664-997-0198-1 PG 4 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA XF164 UT WOS:A1997XF16400020 ER PT J AU Abraham, BM Keith, WL AF Abraham, BM Keith, WL TI Wavenumber spectra of high magnitude wall pressure events in a numerically simulated turbulent boundary layer SO JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID FLOW; FLUCTUATIONS; BENEATH AB A method for conditionally sampling the spatial field of the wall pressure beneath a turbulent boundary layer in order to search for high magnitude events and calculate the corresponding wavenumber spectrum is presented. The high magnitude events are found using a simple peak detection algorithm at a fixed instant in time and the wavenumber spectra are calculated using discrete Fourier transforms. The frequency of occurrence Soi high magnitude positive events is found to be approximately the same as for high magnitude negative events. The contribution of the high magnitude events to the rms wall pressure for various trigger levels is calculated and compared with results from similar experimental studies performed in the time domain. The high magnitude events are shown to occur infrequently and to contribute significantly to the rms wall pressure. Wavenumber spectra from the high magnitude positive and negative events are calculated and compared with the unconditionally sampled spectra. The high magnitude events contain energy focused around a particular streamwise wavenumber and have high broadband spectral levels. RP Abraham, BM (reprint author), USN,CTR UNDERSEA WARFARE,SUBMARINE SONAR DEPT,NEWPORT,RI 02841, USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0098-2202 J9 J FLUID ENG-T ASME JI J. Fluids Eng.-Trans. ASME PD JUN PY 1997 VL 119 IS 2 BP 281 EP 288 DI 10.1115/1.2819132 PG 8 WC Engineering, Mechanical SC Engineering GA XE299 UT WOS:A1997XE29900006 ER PT J AU Gavrishchaka, VV Koepke, ME Ganguli, GI AF Gavrishchaka, VV Koepke, ME Ganguli, GI TI Ion cyclotron modes in a two-ion-component plasma with transverse-velocity shear SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID AURORAL FIELD LINES; MAGNETIC-FIELD; ELECTROSTATIC-WAVES; ELECTRIC-FIELD; DUSTY PLASMAS; ALFVEN WAVES; HEAVY-IONS; INSTABILITY; TURBULENCE; SIMULATION AB Electrostatic ion cyclotron fluctuations driven by combination of a magnetic-field-aligned electron current and a localized transverse electric field in two-ion-component plasmas are investigated through the use of nonlocal linear theory for a collisionless plasma. The emphasis is on the stability properties of these modes as a function of relative concentration of plasma components. For various characteristic parameters, such as the spatial dimension of the inhomogeneous electric field profile, magnitude of the E x B velocity, magnitude of the field-aligned current, and temperature ratio tau = T-i/T-e, it is shown that in contrast to the homogeneous case of the current-driven ion cyclotron mode, the ion cyclotron modes in the presence of a transverse-velocity shear can be unstable in a significantly wider range of relative concentration ratios. Moreover, positive growth rates are possible for relatively small and even zero values of field-aligned current in the inhomogeneous electric field case. The mode characteristics in the two cases differ significantly. For example, in the inhomogeneous case, the frequency spectrum is broadband including frequencies much smaller than ion gyrofrequency. The relevance of these results to ionospheric observations is discussed. C1 USN, RES LAB, DIV PLASMA PHYS, WASHINGTON, DC 20375 USA. W VIRGINIA UNIV, DEPT PHYS, MORGANTOWN, WV 26506 USA. NR 57 TC 13 Z9 13 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD JUN 1 PY 1997 VL 102 IS A6 BP 11653 EP 11663 DI 10.1029/97JA00639 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XD974 UT WOS:A1997XD97400035 ER PT J AU Riley, JL Carroll, RG Levine, BL Bernstein, W StLouis, DC Weislow, OW June, CH AF Riley, JL Carroll, RG Levine, BL Bernstein, W StLouis, DC Weislow, OW June, CH TI Intrinsic resistance to T cell infection with HIV type 1 induced by CD28 costimulation SO JOURNAL OF IMMUNOLOGY LA English DT Article ID IMMUNODEFICIENCY-VIRUS TYPE-1; IN-VITRO; MONOCLONAL-ANTIBODIES; HUMAN MACROPHAGES; INTERFERON-ALPHA; CROSS-LINKING; REPLICATION; ACTIVATION; ANTIGEN; CD4 AB When HIV-infected leukocytes are activated by the CD28 costimulatory receptor, HIV-1 is rapidly cleared from cultures, suggesting that costimulation can render T cells resistant to HIV-1 infection, In this study we tested the hypothesis that enhanced secretion of cytokines or chemokines could account for CD28-induced antiviral effects. In an acute infection system, resistance to infection with macrophage-tropic strains of HIV-1 was shown to be comprised of both soluble and cell-associated components, Induction of HIV-1 resistance was specific for CD28 costimulation, in that a variety of other accessory receptors, such as CD2, CD4, CD5, and MHC class I, failed to confer the antiviral resistance, The soluble component was secreted by both CD4 and CD8 T cells, was not unique to CD28 costimulation, and could be neutralized by removal of C-C chemokines (RANTES (regulated upon activation, normal T cell expressed and secreted) and macrophage inflammatory protein-1 alpha and -1 beta) from the culture supernatants of costimulated CD4 T cells, In contrast, CD28 stimulation of CD4 cells resulted in the specific induction of a pronounced intrinsic resistance to HIV-1 infection by macrophage tropic isolates of HIV-1. C1 USN,MED RES INST,IMMUNE CELL BIOL PROGRAM,BETHESDA,MD 20889. WALTER REED ARMY INST RES,DIV RETROVIROL,ROCKVILLE,MD. SRA TECHNOL,DIV LIFE SCI,ROCKVILLE,MD 20850. SRA TECHNOL,HENRY M JACKSON FDN ADVANCEMENT MIL MED,ROCKVILLE,MD 20850. UNIFORMED SERV UNIV HLTH SCI,DEPT MED,BETHESDA,MD 20814. UNIFORMED SERV UNIV HLTH SCI,DEPT MOL & CELL BIOL,BETHESDA,MD 20814. RI Levine, Bruce/D-1688-2009; OI Riley, James/0000-0002-1057-576X NR 55 TC 53 Z9 53 U1 0 U2 0 PU AMER ASSOC IMMUNOLOGISTS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 SN 0022-1767 J9 J IMMUNOL JI J. Immunol. PD JUN 1 PY 1997 VL 158 IS 11 BP 5545 EP 5553 PG 9 WC Immunology SC Immunology GA XA063 UT WOS:A1997XA06300063 PM 9164979 ER PT J AU Barkyoumb, JH Mathur, VK Lewandowski, AC Tookey, A Townsend, PD Giblin, I AF Barkyoumb, JH Mathur, VK Lewandowski, AC Tookey, A Townsend, PD Giblin, I TI Low-temperature luminescence properties of CaSO4:Dy SO JOURNAL OF LUMINESCENCE LA English DT Article; Proceedings Paper CT 1996 International Conference on luminescence and Optical Spectroscopy of Condensed Matter (ICL 96) CY AUG 18-23, 1996 CL PRAGUE, CZECH REPUBLIC SP Charles Univ, Fac Math & Phys, Acad Sci Czech Republic, Inst Phys, Czech Minist Educ Youth & Sport, Int Union Pure & Appl Phys, European Commiss, WE Heraeus Fdn DE tunnel luminescence; thermoluminescence; TL emission; CaSO4 ID THERMOLUMINESCENT AB The low-temperature luminescence properties of CaSO4:Dy for personnel dosimetry have yet to be fully investigated. In this article we present the results of low-temperature TL, radioluminescence and phosphorescence to demonstrate the existence of tunnel luminescence as opposed to thermoluminescence (TL) from low-temperature traps and attempt to explain the subtle difference between high-temperature TL, low-temperature TL and tunnel luminescence spectra. C1 OPTEX COMMUN CORP,ROCKVILLE,MD 20850. UNIV SUSSEX,BRIGHTON BN1 9QH,E SUSSEX,ENGLAND. RP Barkyoumb, JH (reprint author), USN,CTR SURFACE WARFARE,CARDEROCK DIV,WHITE OAK SITE,CODE 682,9500 MAC ARTHUR BLVD,BETHESDA,MD 20817, USA. NR 8 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-2313 J9 J LUMIN JI J. Lumines. PD JUN PY 1997 VL 72-4 BP 629 EP 632 DI 10.1016/S0022-2313(96)00153-6 PG 4 WC Optics SC Optics GA XK428 UT WOS:A1997XK42800240 ER PT J AU Dhote, AM Madhukar, S Young, D Venkatesan, T Ramesh, R Cotell, CM Benedetto, JM AF Dhote, AM Madhukar, S Young, D Venkatesan, T Ramesh, R Cotell, CM Benedetto, JM TI Low temperature growth and reliability of ferroelectric memory cell integrated on Si with conducting barrier stack SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID THIN-FILMS; HETEROSTRUCTURES; FABRICATION; CAPACITORS; ELECTRODES; FATIGUE; LAYERS AB Polycrystalline LSCO/PNZT/LSCO ferroelectric capacitor heterostructures were grown by pulsed laser deposition using a composite conducting barrier layer of Pt/TiN on poly Si/Si substrate, The growth of the ferroelectric heterostructure is accomplished at a temperature in the range of 500-600 degrees C, This integration results in a 3-dimensional stacked capacitor-transistor geometry which is important for high density nonvolatile memory (HDNVM) applications, Transmission electron microscopy shows smooth substrate-film and film-film interfaces without any perceptible interdiffusion, The ferroelectric properties and reliability of these integrated capacitors were studied extensively at room temperature and 100 degrees C for different growth temperatures. The capacitors exhibit excellent reliability, both at room temperature and at elevated temperatures, making them very desirable for HDNVM applications. C1 USN,RES LAB,SURFACE MODIFICAT BRANCH,WASHINGTON,DC 20375. USA,RES LABS,ADELPHI,MD 20783. RP Dhote, AM (reprint author), UNIV MARYLAND,DEPT MAT & NUCL ENGN,COLLEGE PK,MD 20742, USA. RI Venkatesan, Thirumalai/E-1667-2013 NR 26 TC 7 Z9 7 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD JUN PY 1997 VL 12 IS 6 BP 1589 EP 1594 DI 10.1557/JMR.1997.0218 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA XC344 UT WOS:A1997XC34400026 ER PT J AU Overfelt, PL AF Overfelt, PL TI Comment on: On the evanescent fields and the causality of the focus wave modes SO JOURNAL OF MATHEMATICAL PHYSICS LA English DT Editorial Material RP Overfelt, PL (reprint author), USN,PHYS BRANCH,RES & TECHNOL GRP,AIR WARFARE CTR WEAP DIV,CHINA LAKE,CA 93555, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0022-2488 J9 J MATH PHYS JI J. Math. Phys. PD JUN PY 1997 VL 38 IS 6 BP 3391 EP 3395 DI 10.1063/1.532049 PG 5 WC Physics, Mathematical SC Physics GA XC695 UT WOS:A1997XC69500040 ER PT J AU Harbison, BB Merzbacher, CI Aggarwal, ID AF Harbison, BB Merzbacher, CI Aggarwal, ID TI Preparation and properties of BaS-Ga2S3-GeS2 glasses SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 10th International Symposium on Non-Oxide Glasses CY JUN 19-22, 1996 CL CORNING, NY SP Alfred Univ, Corning Inc ID SYSTEM AB A new class of sulfide glasses based upon the BaS-Ga2S3-GeS2 system has been investigated. Glass compositions were prepared in graphite or vitreous carbon crucibles. encapsulated in silica ampoules. and cooled from a melt temperature of 1000 degrees C. These glasses have good glass stability, with T-x-T-g in the range of 100 to 200 degrees C, glass transition temperatures between 400 and 500 degrees C, and infrared transmission to wavelengths of about 12 mu m Thermal, optical and mechanical properties of these glasses are reported and the effects of materials purity and processing on these properties are discussed. Their thermal stability and optical transmission band make these glasses candidate materials for rare earth doped lasers and fiber amplifiers, infrared fiber sensors and optical components for infrared systems. RP Harbison, BB (reprint author), USN,RES LAB,DIV OPT SCI,WASHINGTON,DC 20375, USA. NR 13 TC 19 Z9 19 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD JUN PY 1997 VL 213 BP 16 EP 21 DI 10.1016/S0022-3093(97)00039-2 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA XG221 UT WOS:A1997XG22100005 ER PT J AU Sanghera, JS Aggarwal, ID AF Sanghera, JS Aggarwal, ID TI Development of chalcogenide glass fiber optics at NRL SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 10th International Symposium on Non-Oxide Glasses CY JUN 19-22, 1996 CL CORNING, NY SP Alfred Univ, Corning Inc AB We have fabricated unclad sulphide and telluride chalcogenide fibers with losses of 0.047 dB/m at 2.4 mu m and 0.11 dB/m at 6.6 mu m, respectively. Core/clad fibers with losses approaching 0.5 dB/m at 4.8 mu m have been fabricated in long fiber lengths (similar to 50 m). While theoretical minimum losses are estimated to be about 4 dB/km at around 5 mu m for sulphide fibers, we have identified the absorption and scattering mechanisms which limit the practical losses. The bending strengths of these fibers have been measured and are satisfactory for short length applications. For longer lengths, both the loss and strength need to be improved. RP Sanghera, JS (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 14 TC 43 Z9 45 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD JUN PY 1997 VL 213 BP 63 EP 67 DI 10.1016/S0022-3093(97)00051-3 PG 5 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA XG221 UT WOS:A1997XG22100014 ER PT J AU Bayya, SS Harbison, BB Sanghera, JS Aggarwal, ID AF Bayya, SS Harbison, BB Sanghera, JS Aggarwal, ID TI BaO-Ga2O3-GeO2 glasses with enhanced properties SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article ID GERMANATE GLASSES; LA AB Varying substitutions of In2O3 for Ga2O3 in the BaO-Ga2O3-GeO2 glasses were made and their effects on the glass transition temperature, density, hardness, chemical durability and the infrared transmission were studied. In2O3 substitution for Ga2O3, in general, resulted in improvement in the physical properties of these glasses, The glass transition temperature, density and hardness increased with the substitution. The chemical durability of these glasses improved with the substitutions and the infrared (IR) cut-off edge shifted to longer wavelengths. Phase separation was observed in compositions with higher In2O3 substitutions. The observed changes in physical properties and phase separation with In2O3 substitutions are explained on the basis of a structural model suggesting that octahedrally coordinated In3+ replaces tetrahedrally coordinated Ga3+ in the glass structure. The observed results are in good agreement with the model which also explains the phase separation observed at higher In2O3 substitutions. C1 USN, RES LAB, WASHINGTON, DC 20375 USA. RP VIRGINIA POLYTECH INST & STATE UNIV, BLACKSBURG, VA 24061 USA. NR 28 TC 27 Z9 31 U1 3 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 EI 1873-4812 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD JUN 1 PY 1997 VL 212 IS 2-3 BP 198 EP 207 DI 10.1016/S0022-3093(96)00658-8 PG 10 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA XC980 UT WOS:A1997XC98000012 ER PT J AU Jayne, SR Tokmakian, R AF Jayne, SR Tokmakian, R TI Forcing and sampling of ocean general circulation models: Impact of high-frequency motions SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article AB Significant inertial oscillations are present in all primitive equation ocean general circulation models when they are forced with high-frequency (period order of days) wind stress fields. At specific latitudes the energy of the wind stress forcing near the frequency of the inertial oscillations excites large amplitudes in the surface kinetic energy. The frequently used strategy of subsampling model output at several day intervals then leads to aliasing of the energetic inertial currents into lower frequencies that vary with latitude, which severely corrupts even integral quantities like meridional heat transport. This note discusses the effect of forcing and sampling at short periods. Schemes are provided that will remove the aliased energy from the model fields stored for later analysis. C1 USN,POSTGRAD SCH,DEPT OCEANOG,MONTEREY,CA 93943. RP Jayne, SR (reprint author), WOODS HOLE OCEANOG INST,MIT,JOINT PROGRAM OCEANOG,CLARK 3,MS 21,WOODS HOLE,MA 02543, USA. NR 12 TC 21 Z9 21 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0022-3670 J9 J PHYS OCEANOGR JI J. Phys. Oceanogr. PD JUN PY 1997 VL 27 IS 6 BP 1173 EP 1179 DI 10.1175/1520-0485(1997)027<1173:FASOOG>2.0.CO;2 PG 7 WC Oceanography SC Oceanography GA XR046 UT WOS:A1997XR04600020 ER PT J AU Ko, SH AF Ko, SH TI Reduction of structure-borne noise using an air-voided elastomer SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article; Proceedings Paper CT 130th Meeting of the Acoustical-Society-of-America CY NOV 27-DEC 01, 1995 CL ST LOUIS, MO SP Acoust Soc Amer AB A theoretical model was developed to evaluate the reduction of structure-borne noise that is generated by a line force applied on an infinite plate using an air-voided elastomeric baffle. The vibrating plate is covered with an elastomeric baffle layer to reduce the noise generated by the structural vibration. The vibrating plate is perfectly banded to the elastomeric baffle layer. The outer surfaces of the vibrating plate and the elastomeric baffle are In contact with air and water, respectively. The analysis for modeling is based on the theory of elasticity and pertinent boundary conditions. Effects of various parameters such as baffle layer dimensions and material properties on the noise reduction are presented. RP Ko, SH (reprint author), USN,UNDERSEA WARFARE CTR DIV,NEWPORT,RI 02841, USA. NR 8 TC 21 Z9 24 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JUN PY 1997 VL 101 IS 6 BP 3306 EP 3312 DI 10.1121/1.418292 PG 7 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA XE288 UT WOS:A1997XE28800011 ER PT J AU Badiey, M Simmen, J Forsythe, S AF Badiey, M Simmen, J Forsythe, S TI Frequency dependence of broadband propagation in coastal regions SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB To study the frequency-dependent spatial and temporal variabilities of sound propagation in coastal regions two experiments were conducted by transmitting sound impulses in the form of M sequences centered from 0.6 to 22 kHz. The site of the first experiment was the Atlantic Generating Station (AGS) where the source-receiver range was 214 m. The site of the second experiment was Delaware Bay where the range was approximately 760 m. The mean water depth was 14-15 m in both locations. Oceanographic data and acoustic data were collected simultaneously in both experiments. It was found that the temporal coherence of the propagated broadband signal changes significantly with pulse center frequency, as well as varying with geographic location and time. Trends of increasing signal decorrelation (between consecutive pulses) with increasing center frequency, and increasing signal decorrelation for paths with increasing number of interface interactions, were observed. It was found that for lower center frequencies there is hardly any decorrelation in signal over several hours, while for signals with center frequencies only a few kHz higher there was substantial decorrelation over times as short as 10 to 20 min. No significant spatial decorrelation of the signal was observed over the hydrophone spacing of a few meters for these experiments. (C) 1997 Acoustical Society of America. C1 OFF NAVAL RES,OCEAN ACOUST PROGRAM,ARLINGTON,VA 22217. USN,UNDERSEA WARFARE CTR,UNDERWATER SOUND REFERENCE DETACHMENT,ORLANDO,FL 32856. RP Badiey, M (reprint author), UNIV DELAWARE,GRAD COLL MARINE STUDIES,OCEAN ACOUST LAB,NEWARK,DE 19716, USA. RI Badiey, Mohsen/H-3943-2012 NR 12 TC 11 Z9 11 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JUN PY 1997 VL 101 IS 6 BP 3361 EP 3370 DI 10.1121/1.418350 PG 10 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA XE288 UT WOS:A1997XE28800018 ER PT J AU Bowles, FA AF Bowles, FA TI Observations on attenuation and shear-wave velocity in fine-grained, marine sediments SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID PHYSICAL-PROPERTIES; SEA-FLOOR; ACOUSTIC PROPERTIES; SOUND-VELOCITY; SHALLOW-WATER; DEEP OCEAN; DEPTH; BOTTOM; BASIN; PROPAGATION AB Compressional(P)-wave attenuation, shear(S)-wave attenuation, and shear(S)-wave velocity measurements, compiled for fine-grained, unconsolidated sediments, show trends that do not support empirical relationships [Hamilton, J. Acoust. Soc. Am. 68, 1313-1340 (1980); in Acoustics and Ocean Bottom (F. A. S. E. Specialize Conf., Madrid, 1987)] commonly used for geoacoustic modeling. The exception is compressional-wave attenuation data, from 10 Hz to 500 kHz, that essentially follow a frequency dependence of f(1) (+/-2 standard deviations). P-wave attenuation with depth is difficult, if not impossible, to predict given the variability in the data. Examination of several attenuation/depth profiles indicates that those of Mitchell and Focke [J. Acoust. Sec. Am. 67, 1582-1589 (1980)] may be the best choice for predicting P-wave attenuation with depth at the present time. The assumption that S-wave and F-wave attenuations are proportional [Hamilton, J. Acoust. Sec. Am. 60, 334-338 (1976c); in Acoustics and Ocean Bottom (F. A. S. E. Specialize Conf., Madrid, 1987)] is not supported by the data. S-wave attenuations calculated from effective stress mimmick the data, however, suggesting this as a better method for predicting S-wave attenuation with depth. S-wave velocity/depth profiles fall into high- and low-velocity groups that (1) reflect gross differences in sediment texture, and (2) demonstrate the importance of sediment characterization in order to select an appropriate velocity/depth function. RP Bowles, FA (reprint author), USN,RES LAB,MARINE GEOSCI DIV,STENNIS SPACE CTR,MS 39529, USA. NR 96 TC 38 Z9 38 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JUN PY 1997 VL 101 IS 6 BP 3385 EP 3397 DI 10.1121/1.419374 PG 13 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA XE288 UT WOS:A1997XE28800020 ER PT J AU Fialkowski, LT Collins, MD Perkins, JS Kuperman, WA AF Fialkowski, LT Collins, MD Perkins, JS Kuperman, WA TI Source localization in noisy and uncertain ocean environments SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID MATCHED-FIELD LOCALIZATION; SHALLOW-WATER; SOURCE TRACKING; SOUND-SPEED; MISMATCH; SENSITIVITY; RESOLUTION; ACOUSTICS AB Interference from noise and uncertainties in the environmental parameters are arguably the two most serious limitations in matched-field processing (MFP). Among the techniques that have been developed for handling these difficulties are the noise-canceling processor [M. D. Collins, N. C. Makris, and L. T. Fialkowski, ''Noise cancellation and source localization,'' J. Acoust. Sec. Am. 96, 1773-1776 (1994)] and focalization [M. D. Collins and W. A. Kuperman, ''Focalization: Environmental focusing and source localization,'' J. Acoust. Sec. Am. 90, 1410-1422 (1991)]. The noise-canceling processor is a generalization of the Bartlett processor that is based on matching the covariance matrix of the data with replica covariance matrices of the signal and the noise. Simulations are presented to illustrate the performance of the noise-canceling processor when there are errors in the noise replica. Focalization is a generalization of MFP in which environmental parameters are included along with source parameters in the search space. An implementation of this approach that is suitable for applications is developed and tested. The noise-canceling processor and focalization are used to simulate the localization of a source buried in noise in an uncertain environment. (C) 1997 Acoustical Society of America. C1 UNIV CALIF SAN DIEGO,SCRIPPS INST OCEANOG,LA JOLLA,CA 92093. RP Fialkowski, LT (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 26 TC 12 Z9 12 U1 1 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JUN PY 1997 VL 101 IS 6 BP 3539 EP 3545 DI 10.1121/1.418314 PG 7 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA XE288 UT WOS:A1997XE28800034 ER PT J AU VanCott, TC Mascola, JR Kaminski, RW Kalyanaraman, V Hallberg, PL Burnett, PR Ulrich, JT Rechtman, DJ Birx, DL AF VanCott, TC Mascola, JR Kaminski, RW Kalyanaraman, V Hallberg, PL Burnett, PR Ulrich, JT Rechtman, DJ Birx, DL TI Antibodies with specificity to native gp120 and neutralization activity against primary human immunodeficiency virus type 1 isolates elicited by immunization with oligomeric gp160 SO JOURNAL OF VIROLOGY LA English DT Article ID BIOSPECIFIC INTERACTION ANALYSIS; ENVELOPE GLYCOPROTEIN GP120; RECOMBINANT VACCINIA VIRUS; EXPRESSING HIV ENVELOPE; T-CELL LINE; SOLUBLE CD4; MONOCLONAL-ANTIBODIES; SERONEGATIVE VOLUNTEERS; CANDIDATE VACCINE; EPITOPE EXPOSURE AB Current human immunodeficiency virus type I (HIV-I) envelope vaccine candidates elicit high antibody binding titers with neutralizing activity against T-cell line-adapted but not primary HIV-1 isolates. Serum antibodies from these human vaccine recipients were also found to be preferentially directed to linear epitopes within gp120 that are poorly exposed on native gp120. Systemic immunization of rabbits with an affinity-purified oligomeric gp160 protein formulated with either Alhydrogel or monophosphoryl lipid A-containing adjuvants resulted in the induction of high-titered serum antibodies that preferentially bound epitopes exposed on native forms of gp120 and gp160, recognized a restricted number of linear epitopes, efficiently bound heterologous strains of monomeric gp120 and cell surface-expressed oligomeric gp120/gp41, and neutralized several strains of T-cell line-adapted HIV-1. Additionally, those immune sera with the highest oligomeric gp160 antibody binding titers had neutralizing activity against some primary HIV-1 isolates, using phytohemagglutinin-stimulated peripheral blood mononuclear cell targets. Induction of an antibody response preferentially reactive with natively folded gp120/gp160 was dependent on the tertiary structure of the HIV-1 envelope immunogen as well as its adjuvant formulation, route of administration, and number of immunizations administered. These studies demonstrate the capacity of a soluble HIV-1 envelope glycoprotein vaccine to elicit an antibody response capable of neutralizing primary HIV-1 isolates. C1 WALTER REED ARMY INST RES,DIV RETROVIROL,ROCKVILLE,MD 20850. ADV BIOSCI LABS,KENSINGTON,MD 20895. RIBI IMMUNOCHEM RES INC,HAMILTON,MT 59840. USN,MED RES INST,DEPT INFECT DIS,BETHESDA,MD 20889. RP VanCott, TC (reprint author), HENRY M JACKSON FDN,13 TAFT CT,SUITE 200,ROCKVILLE,MD 20850, USA. NR 67 TC 102 Z9 105 U1 0 U2 0 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 SN 0022-538X J9 J VIROL JI J. Virol. PD JUN PY 1997 VL 71 IS 6 BP 4319 EP 4330 PG 12 WC Virology SC Virology GA WZ571 UT WOS:A1997WZ57100017 PM 9151820 ER PT J AU Olsen, EA AF Olsen, EA TI Coping with the Korean peace process: An American view SO KOREAN JOURNAL OF DEFENSE ANALYSIS LA English DT Article AB Even as the debate proceeds about whether and how the two Koreas will reunite, peacefully or traumatically, it is essential that the US-ROK alliance partners give serious consideration to how they will adjust to peace in Korea. They need to address both a uniting Korea and the impact of a united Korea regionally. It is virtually a given that the major powers shall have facilitating and sanctioning roles in the Korean peace process. Many venues are conceivable and any one that is successful at creating a lasting peace in Korea will deserve praise. At the present time the four-party proposal is prominent. If it succeeds, that will be sufficient. If it does not produce better results than previous attempts, it may be time to adapt the Camp David or Dayton model to the Korean situation. Using this two-plus-one formula the US has the potential to be a catalyst for Korean peace and do as much for Korea as it has done for the Middle East and the Balkans. Regardless which course the Korean peace process takes, it will not necessarily portend rapid movement toward complete unification. There could well be an interim phase in which two Koreas could co-exist for a prolonged period. In fact, given the daunting costs of unification, an interim regime in North Korea may be preferable. In that light, Seoul and Washington may wish to develop a coordinated policy designed to induce the leaders in Pyongyang to develop an interim regime. The most appropriate way to pursue that goal would be to help the North Koreans reformulate their brand of nationalism so that it will converge with South Korea. Other, more manipulative methods also might be of use. Whether Korea unifies relatively suddenly or on an incremental basis, Asia and outside powers concerned with Asia are likely to be confronted with the consequences of success in the Korea peace process in the not too distant future. Although there are various ways to visualize that future, here six prospective scenarios are raised. As an American analyst, special attention is paid to the impact they could have on US-Korean relations. Conventional wisdom anticipates basic strategic continuity with a strong Korea. Clearly this is preferred by the US and ROK governments. This scenario could be troubled by shifting perceptions of Chinese and Japanese relations with Korea and the changing nature of Korean security attitudes. On the other hand, peace in Korea could yield a state weakened by the process and the costs, a Korea overshadowed by China or Japan in US eyes, a hyper-nationalistic Korea that rejects the US, a Korea (weak or strong) that ceases to matter much to a US preoccupied by domestic affairs, or a Korea which fails to make unification work and re-divides. Regardless of which type scenario characterizes Korea in the future, it is important that Seoul and Washington try to prepare for a range of possibilities through better contingency planning. RP Olsen, EA (reprint author), USN,POSTGRAD SCH,CTR NE ASIAN SECUR STUDIES,MONTEREY,CA 93943, USA. NR 47 TC 0 Z9 0 U1 1 U2 2 PU KOREAN INST DEFENSE ANALYSES PI SEOUL PA OFFICE RESEARCH COOPERATION, PO BOX 250, SEOUL 130-650, SOUTH KOREA SN 1016-3271 J9 KOREAN J DEF ANAL JI Korean J. Def. Anal. PD SUM PY 1997 VL 9 IS 1 BP 159 EP & PG 24 WC International Relations SC International Relations GA YE122 UT WOS:A1997YE12200007 ER PT J AU Smoot, NC Leybourne, BA AF Smoot, NC Leybourne, BA TI Vortex structures and the world-encircling vortex street: Case study of the South Adriatic Basin SO MARINE TECHNOLOGY SOCIETY JOURNAL LA English DT Article ID SEA; EVOLUTION; LITHOSPHERE; MICROPLATE; TECTONICS; PACIFIC AB Based on the newer surge tectonic hypothesis, the vortex-feature is immediately recognizable. Defining the present evolution of a vortex structure by analyzing the GEOSAT data base, 3.5 kHz reflection profiles, and available bathymetry shows the South Adriatic Basin to be in a state of rotation and subsidence. Acoustic characters define fault trends and compression zones, with faults trending ESE across the basin. A time-sequence analysis of the regional earthquake data around the vortex structure also shows clockwise rotation. The Adriatic vortex is an integral part of the currently active, equatorial world-encircling vortex street, a geostream of vortex and eddy structures interconnected by active surge channels. C1 USN,OCEANOG OFF,GEOPHYS ACOUST DIV,STENNIS SPACE CTR,MS 39529. RP Smoot, NC (reprint author), USN,OCEANOG OFF,SEAFLOOR DATA BASES DIV,STENNIS SPACE CTR,MS 39529, USA. NR 45 TC 7 Z9 7 U1 0 U2 0 PU MARINE TECHNOLOGY SOC INC PI WASHINGTON PA C/O I CLAYION MATTHEWS, 1828 L ST, NW, 9TH FL, WASHINGTON, DC 20036 SN 0025-3324 J9 MAR TECHNOL SOC J JI Mar. Technol. Soc. J. PD SUM PY 1997 VL 31 IS 2 BP 21 EP 35 PG 15 WC Engineering, Ocean; Oceanography SC Engineering; Oceanography GA XT891 UT WOS:A1997XT89100004 ER PT J AU Atturio, JM Paul, W AF Atturio, JM Paul, W TI State of technology report - Ocean and Coastal Engineering Division SO MARINE TECHNOLOGY SOCIETY JOURNAL LA English DT Article RP Atturio, JM (reprint author), USN,NAVAL FACIL,ENGN SERV CTR,PORT HUENEME,CA 93041, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC INC PI WASHINGTON PA C/O I CLAYION MATTHEWS, 1828 L ST, NW, 9TH FL, WASHINGTON, DC 20036 SN 0025-3324 J9 MAR TECHNOL SOC J JI Mar. Technol. Soc. J. PD SUM PY 1997 VL 31 IS 2 BP 36 EP 49 PG 14 WC Engineering, Ocean; Oceanography SC Engineering; Oceanography GA XT891 UT WOS:A1997XT89100005 ER PT J AU Dangler, E AF Dangler, E TI United Nations Convention on Law of the Sea SO MARINE TECHNOLOGY SOCIETY JOURNAL LA English DT Editorial Material C1 USN,SAN DIEGO,CA 92152. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC INC PI WASHINGTON PA C/O I CLAYION MATTHEWS, 1828 L ST, NW, 9TH FL, WASHINGTON, DC 20036 SN 0025-3324 J9 MAR TECHNOL SOC J JI Mar. Technol. Soc. J. PD SUM PY 1997 VL 31 IS 2 BP 56 EP 59 PG 4 WC Engineering, Ocean; Oceanography SC Engineering; Oceanography GA XT891 UT WOS:A1997XT89100007 ER PT J AU Fisher, WG Meyer, KE Wachter, EA Perl, DR Kulowitch, PJ AF Fisher, WG Meyer, KE Wachter, EA Perl, DR Kulowitch, PJ TI Laser induced fluorescence imaging of thermal damage in polymer matrix composites SO MATERIALS EVALUATION LA English DT Article AB A simple, fluorescence based imaging system has been developed that is capable of identifying regions of thermal damage in polymer matrix composites (PMCs). These materials are playing an increasingly important role in the production of high performance vehicles and air-craft, where their low weight and high mechanical strength, combined with advancements in manufacturing technology ensure increased use for a variety of applications. Of particular concern in the aerospace industry is the tendency of some PMC materials to become irreversibly damaged when exposed to elevated temperatures. Traditional nondestructive testing (NDT) techniques are capable of defecting physical anomalies such as cracks and delaminations but cannot detect initial heat damage, which occurs on a molecular scale. Spectroscopic techniques such as laser induced fluorescence provide an attractive means for detecting this type of damage and are amenable to imaging large, irregularly shaped surfaces. In this report we describe instrumentation capable of rapidly detecting thermal damage in graphite epoxy components and suggest improvements which will enable this technology to make quantitative judgments concerning the mechanical strength properties of heat damaged specimens. C1 USN,NAVAL AVIAT DEPOT,NAS N ISL,SAN DIEGO,CA 92135. USN,NAVAL AIR WARFARE CTR,DIV AIRCRAFT,PATUXENT RIVER,MD 20670. RP Fisher, WG (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 8 TC 3 Z9 3 U1 1 U2 3 PU AMER SOC NON-DESTRUCTIVE TEST PI COLUMBUS PA 1711 ARLINGATE LANE PO BOX 28518, COLUMBUS, OH 43228-0518 SN 0025-5327 J9 MATER EVAL JI Mater. Eval. PD JUN PY 1997 VL 55 IS 6 BP 726 EP 729 PG 4 WC Materials Science, Characterization & Testing SC Materials Science GA XC539 UT WOS:A1997XC53900026 ER PT J AU Little, B Wagner, P AF Little, B Wagner, P TI Myths related to microbiologically influenced corrosion SO MATERIALS PERFORMANCE LA English DT Article ID BACTERIA AB Microbiologically influenced corrosion (MIC) is an extremely complex phenomenon whose understanding requires several disciplines, including microbiology, metallurgy, electrochemistry, and surface chemistry. The following is a review of several myths related to MIC that make proper interpretation even move complicated. RP Little, B (reprint author), USN, RES LAB, BAY ST LOUIS, MS 39529 USA. NR 15 TC 34 Z9 39 U1 0 U2 9 PU NATL ASSOC CORROSION ENG PI HOUSTON PA 1440 SOUTH CREEK DRIVE, HOUSTON, TX 77084-4906 USA SN 0094-1492 J9 MATER PERFORMANCE JI Mater. Perform. PD JUN PY 1997 VL 36 IS 6 BP 40 EP 44 PG 5 WC Materials Science, Characterization & Testing SC Materials Science GA XC709 UT WOS:A1997XC70900019 ER PT J AU Robinson, GE AF Robinson, GE TI Can Islamists be Democrats? The case of Jordan SO MIDDLE EAST JOURNAL LA English DT Article AB In contradistinction to the usual arguments about Islamist movements being the greatest threat to democratic transitions in. the Middle East, the argument below posits that the Islamist movement in Jordan has been a force for democratic expansion since liberalization began there in 1989. It has been so primarily because greater democratization has sewed its organizational interests. As the best-organized political movement in Jordan, the Muslim Brothers have had the greatest interest in easing political restrictions that hindered the pursuit of their various policy goals. C1 UNIV CALIF BERKELEY,CTR MIDDLE EASTERN STUDIES,BERKELEY,CA 94720. RP Robinson, GE (reprint author), USN,POSTGRAD SCH,MONTEREY,CA 93940, USA. NR 17 TC 29 Z9 29 U1 1 U2 3 PU MIDDLE EAST INSTITUTE PI WASHINGTON PA 1761 N STREET NW, CIRCULATION DEPT, WASHINGTON, DC 20036-2882 SN 0026-3141 J9 MIDDLE EAST J JI Middle East J. PD SUM PY 1997 VL 51 IS 3 BP 373 EP 387 PG 15 WC Area Studies SC Area Studies GA XM870 UT WOS:A1997XM87000004 ER PT J AU Wurmser, M AF Wurmser, M TI Israel on the road to peace: Accepting the unacceptable - Flamhaft,Z SO MIDDLE EAST JOURNAL LA English DT Book Review RP Wurmser, M (reprint author), USN ACAD,DEPT POLIT SCI,ANNAPOLIS,MD 21402, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU MIDDLE EAST INSTITUTE PI WASHINGTON PA 1761 N STREET NW, CIRCULATION DEPT, WASHINGTON, DC 20036-2882 SN 0026-3141 J9 MIDDLE EAST J JI Middle East J. PD SUM PY 1997 VL 51 IS 3 BP 446 EP 447 PG 2 WC Area Studies SC Area Studies GA XM870 UT WOS:A1997XM87000015 ER PT J AU Lane, DA AF Lane, DA TI Hospital ship doctrine in the United States Navy: The Halsey effect on scoop-and-sail tactics SO MILITARY MEDICINE LA English DT Article AB Although hospital ships have a long history, naval strategists have paid little attention to their tactical employment in naval and amphibious warfare, Often employed as floating ambulances; operational doctrine for hospital ships did not permit their use as floating combat surgical hospitals until the final amphibious campaigns of World War II. Based on operational archives-ships' logs, war diaries, battle plans, and other official records-this essay traces the evolution of tactical doctrine on hospital ships from Guadalcanal to Inchon, Early in World War II, there were insufficient hospital ships to permit much flexibility in their employment. By the Philippine campaign in 1944, the increased availability of afloat medical assets prompted Third Fleet Commander Vice Admiral William F. Halsey to propose that the ships be used as acute surgical hospitals at the amphibious landing sites rather than as seagoing ambulances. Facing the prospect of a growing number of casualties for the major assaults being planned, Halsey needed to maximize medical and surgical efficacy and return-to-duty rates to conserve the fighting strength of his invasion forces. Admiral Chester A. Nimitz approved Halsey's proposal, and the battle plan at Iwo Jima combined the careful triage of casualties at the waterfront with early, forward employment of hospital ships. Despite more than 21,000 casualties at Iwo Jima, they were handled better than at any previous operation in the Pacific theater, The tactical doctrine for hospital ships suggested by Halsey has since been employed in every major amphibious operation, including Okinawa and Inchon, and has also been used in modern-era contingency and humanitarian missions. RP Lane, DA (reprint author), USN,NAVAL MED CTR SAN DIEGO,PRIMARY CARE GRP,2650 STOCKTON RD,BLDG 624,SAN DIEGO,CA 92133, USA. NR 12 TC 1 Z9 1 U1 1 U2 3 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 SN 0026-4075 J9 MIL MED JI Milit. Med. PD JUN PY 1997 VL 162 IS 6 BP 388 EP 395 PG 8 WC Medicine, General & Internal SC General & Internal Medicine GA XD115 UT WOS:A1997XD11500009 PM 9183159 ER PT J AU Oyofo, BA Peruski, LF Ismail, TF ElEtr, SH Churilla, AM Wasfy, MO Petruccelli, BP Gabriel, ME AF Oyofo, BA Peruski, LF Ismail, TF ElEtr, SH Churilla, AM Wasfy, MO Petruccelli, BP Gabriel, ME TI Enteropathogens associated with diarrhea among military personnel during Operation Bright Star 96, in Alexandria, Egypt SO MILITARY MEDICINE LA English DT Article ID ENTEROADHERENT ESCHERICHIA-COLI; HEAT-STABLE TOXIN; TRAVELERS DIARRHEA; CHILDHOOD DIARRHEA; STRAINS; ANTIGENS; ETIOLOGY; DISEASE; AGENTS; DNA AB This study investigated the microbial causes of diarrheal disease among U.S. troops deployed near Alexandria, Egypt, during October 1995, Bacterial causes associated with 19 cases of diarrhea included: enterotoxigenic Escherichia coli (ETEC), 42% (21% heat-stable, 11% heat-labile, and 11% heat-stable/heat-labile producers); enteropathogenic E. coli (5.3%); and enteroadherent E. coli (42%). Four cases of diarrhea were as sociated with enteroaggregative E. coli based on probe analysis for enteroaggregative heat;stable enterotoxin 1. Protozoan causes included: Entamoeba histolytica (11%), E. hartmanni (5%), E. nana (5%), Blastocystis hominis (5%), Chilomastix mesnili (11%), Dientamoeba fragilis (5%), Entamoeba coli (5%), and Cryptosporidium (5%). Shigella, Aeromonas, Plesiomonas, Vibrio, Campylobacter, and Salmonella were not detected. Of the eight ETEC cases,one was colonization factor antigen (CFA)/I only, one was both CFA/I and CFA/III, three were CFA/II, two were CFA/IV, and two were CFA-negative. Antibiograms of the ETEC and enteroadherent E. coli strains showed that all isolates were susceptible to norfloxacin, ciprofloxacin, and nalidixic acid but resistant to ampicillin, tetracycline, chloramphenicol, and sulfamethoxazole. RP Oyofo, BA (reprint author), USN,NAVAL MED RES UNIT 3,RES SCI DEPT,PSC 452,BOX 5000,FPO,AE 09835, USA. NR 32 TC 27 Z9 30 U1 1 U2 1 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 SN 0026-4075 J9 MIL MED JI Milit. Med. PD JUN PY 1997 VL 162 IS 6 BP 396 EP 400 PG 5 WC Medicine, General & Internal SC General & Internal Medicine GA XD115 UT WOS:A1997XD11500010 PM 9183160 ER PT J AU Conrad, KA Kiser, WR AF Conrad, KA Kiser, WR TI Response to doxycycline vs. mefloquine SO MILITARY MEDICINE LA English DT Letter RP Conrad, KA (reprint author), USN,WASHINGTON,DC 20350, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 SN 0026-4075 J9 MIL MED JI Milit. Med. PD JUN PY 1997 VL 162 IS 6 BP R3 EP R3 PG 1 WC Medicine, General & Internal SC General & Internal Medicine GA XD115 UT WOS:A1997XD11500004 PM 9183154 ER PT J AU Thompson, WT Burk, SD Rosenthal, J AF Thompson, WT Burk, SD Rosenthal, J TI An investigation of the Catalina eddy SO MONTHLY WEATHER REVIEW LA English DT Article ID MODEL; PREDICTION; CALIFORNIA; LAYERS AB The Catalina eddy event of 21 July 1992 is simulated using a mesoscale data assimilation system featuring an optimum interpolation analysis, incremental update, and second-order closure physics. The results are contrasted with other recent modeling studies of the Catalina eddy. Genesis of the eddy occurs when changes on the synoptic scale lead to an intensification of the east-west pressure gradient near the coast, resulting in enhanced northwesterly flow along the coast and over the mountains east of Point Conception. Lee troughing results in an alongshore pressure gradient at the coast with higher pressure to the south. Topographically trapped, ageostrophic southerly flow is then initiated. The combination of southerly flow along the coast with strong northwesterly flow to the west results in formation of a cyclonic eddy in the bight. The zone of southerly flow is. characterized by a deep, cool, cloud-topped boundary layer that can considerably alter coastal weather and impact activities involved with aviation, air quality, fire weather, and microwave refractivity. While other recent modeling studies have failed to properly represent boundary layer structure, the data assimilation system used in the present study reproduces these features. Results show that the model forecast eddy is in relatively good agreement with surface wind observations. The data assimilation system, which consists of the analysis-initialization scheme and the forecast model, retains much of the mesoscale structure of the forecast, while adjusting the position of the eddy to better fit the observations. Within the zone of southerly flow, rapid deepening of the boundary layer is accompanied by the formation of stratus clouds. Through the use of sensitivity studies, the authors demonstrate that the deepening of the boundary layer results from convergence and upward motion forced by the topographic barrier along the coast and that the interaction between clouds and radiation plays a significant role. C1 USN, AIR WARFARE CTR, WEAPONS DIV, GEOPHYS BRANCH, POINT MUGU NAWC, CA USA. RP USN, RES LAB, MARINE METEOROL DIV, 7 GRACE HOPPER AVE, MONTEREY, CA 93943 USA. NR 20 TC 20 Z9 20 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 EI 1520-0493 J9 MON WEATHER REV JI Mon. Weather Rev. PD JUN PY 1997 VL 125 IS 6 BP 1135 EP 1146 DI 10.1175/1520-0493(1997)125<1135:AIOTCE>2.0.CO;2 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA XD651 UT WOS:A1997XD65100007 ER PT J AU Brown, GG Cormican, KJ Lawphongpanich, S Widdis, DB AF Brown, GG Cormican, KJ Lawphongpanich, S Widdis, DB TI Optimizing submarine berthing with a persistence incentive SO NAVAL RESEARCH LOGISTICS LA English DT Article AB Submarine berthing plans reserve mooring locations for inbound U.S. Navy nuclear submarines prior to their port entrance. Once in port, submarines may be shifted to different berthing locations to allow them to better receive services they require or to make way for other shifted vessels. However, submarine berth shifting is expensive, labor intensive, and potentially hazardous. This article presents an optimization model for submarine berth planning and demonstrates it with Naval Submarine Base, San Diego. After a berthing plan has been approved and published, changed requests for services, delays, and early arrival of inbound submarines are routine events, requiring frequent revisions. To encourage trust in the planning process, the effect on the solution of revisions in the input is kept small by incorporating a persistence incentive in the optimization model. (C) 1997 John Wiley & Sons, Inc. C1 USN,POSTGRAD SCH,DEPT OPERAT RES,MONTEREY,CA 93943. NR 11 TC 39 Z9 44 U1 0 U2 2 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0894-069X J9 NAV RES LOG JI Nav. Res. Logist. PD JUN PY 1997 VL 44 IS 4 BP 301 EP 318 PG 18 WC Operations Research & Management Science SC Operations Research & Management Science GA WU458 UT WOS:A1997WU45800001 ER PT J AU Sahin, I Crane, JW Watson, KP AF Sahin, I Crane, JW Watson, KP TI Application of a panel method to hydrodynamics of underwater vehicles SO OCEAN ENGINEERING LA English DT Article AB A low-order singularity panel method based on Green's formulation is used to predict the hydrodynamics characteristics of underwater vehicles. The low-order modeling employs constant strength sources and doublets, and the body surface is modeled by quadrilaterals. The method is first applied to predicting the force and moment coefficients of underwater Vehicles for the body-alone and finned configurations. Hydrodynamic coefficients of added mass and added moment of inertia are also calculated by modifying the code. Results for several two and three-dimensional bodies show the usefulness of the method for predicting the added mass and added moment of inertia. (C) 1997 Elsevier Science Ltd. C1 USN,CTR SURFACE WARFARE,DAHLGREEN DIV,COASTAL SYST STN,PANAMA CITY,FL 32407. RP Sahin, I (reprint author), WESTERN MICHIGAN UNIV,DEPT MECH & AERONAUT ENGN,KALAMAZOO,MI 49008, USA. NR 21 TC 11 Z9 15 U1 1 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0029-8018 J9 OCEAN ENG JI Ocean Eng. PD JUN PY 1997 VL 24 IS 6 BP 501 EP 512 DI 10.1016/S0029-8018(96)00026-1 PG 12 WC Engineering, Marine; Engineering, Civil; Engineering, Ocean; Oceanography SC Engineering; Oceanography GA WK971 UT WOS:A1997WK97100001 ER PT J AU Kowalski, MP Cruddace, RG Seely, JF Rife, JC Heidemann, KF Heinzmann, U Kleineberg, U Osterried, K Menke, D Hunter, WR AF Kowalski, MP Cruddace, RG Seely, JF Rife, JC Heidemann, KF Heinzmann, U Kleineberg, U Osterried, K Menke, D Hunter, WR TI Efficiency of a multilayer-coated, ion-etched laminar holographic grating in the 14.5-16.0-nm wavelength region SO OPTICS LETTERS LA English DT Article ID LONG-TERM STABILITY; CRYSTAL MONOCHROMATOR; PERFORMANCE; MO/SI; MIRRORS AB The efficiency of an ion-etched laminar holographic grating was measured at near-normal incidence in the 14.5-16.0-nm wavelength range. The grating had an electron-beam-evaporated Mo/Si multilayer coating matched to the grating groove depth. The efficiency peaked at 16.3% in the first inside order at 15.12 nm and 15.0% in the first outside order at 14.94 nm. These are believed to be the highest efficiencies obtained to date from a multilayer-coated laminar grating at near-normal incidence in the EUV (lambda < 30.0 nm). Zero and even orders were almost completely suppressed. The grating groove efficiency in the first order approached the theoretical limit of 40.5%. (C) 1997 Optical Society of America. C1 CARL ZEISS,D-73446 OBERKOCHEN,GERMANY. UNIV BIELEFELD,FAC PHYS,D-33615 BIELEFELD,GERMANY. SFA INC,LARGO,MD 20774. RP Kowalski, MP (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. RI Heinzmann, Ulrich/A-6248-2012 NR 15 TC 30 Z9 30 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD JUN 1 PY 1997 VL 22 IS 11 BP 834 EP 836 DI 10.1364/OL.22.000834 PG 3 WC Optics SC Optics GA XC137 UT WOS:A1997XC13700029 PM 18185678 ER PT J AU Axenrod, T Das, KK Yazdekhasti, H AF Axenrod, T Das, KK Yazdekhasti, H TI An efficient synthesis of 3-bromo-2-(bromomethyl)-1-propene SO ORGANIC PREPARATIONS AND PROCEDURES INTERNATIONAL LA English DT Article ID TRIMETHYLENEMETHANE; POLYAMINES C1 GEOCENTERS INC,ARDEC,LAKE HOPATCONG,NJ 07849. NAVAL SURFACE WARFARE CTR,ENERGET MAT RES & TECHNOL DEPT,INDIAN HEAD,MD 20640. RP Axenrod, T (reprint author), CUNY CITY COLL,DEPT CHEM,NEW YORK,NY 10031, USA. NR 20 TC 6 Z9 6 U1 0 U2 1 PU ORGANIC PREP PROCEDURES INC PI NEWTON HIGHLANDS PA PO BOX 9, NEWTON HIGHLANDS, MA 02161 SN 0030-4948 J9 ORG PREP PROCED INT JI Org. Prep. Proced. Int. PD JUN PY 1997 VL 29 IS 3 BP 358 EP 361 PG 4 WC Chemistry, Organic SC Chemistry GA WW621 UT WOS:A1997WW62100017 ER PT J AU Randall, DA Kang, R Mohs, DC AF Randall, DA Kang, R Mohs, DC TI Use of the miniarthroscopic drill in choanal atresia repair: How we do it SO OTOLARYNGOLOGY-HEAD AND NECK SURGERY LA English DT Article; Proceedings Paper CT 10th Annual Meeting of the American-Society-of-Pediatric-Otolaryngology CY MAY 27-30, 1995 CL DURANGO, CO SP Amer Soc Pediat Otolaryngol C1 USN,MED CTR,DEPT OTOLARYNGOL,SAN DIEGO,CA 92134. RP Randall, DA (reprint author), USN,MED CTR,DEPT CLIN INVEST,SAN DIEGO,CA 92134, USA. NR 7 TC 2 Z9 3 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 SN 0194-5998 J9 OTOLARYNG HEAD NECK JI Otolaryngol. Head Neck Surg. PD JUN PY 1997 VL 116 IS 6 BP 696 EP 697 DI 10.1016/S0194-5998(97)70253-5 PN 1 PG 2 WC Otorhinolaryngology; Surgery SC Otorhinolaryngology; Surgery GA XH410 UT WOS:A1997XH41000026 PM 9215388 ER PT J AU Tsou, VM Bishop, PR Nowicki, MJ AF Tsou, VM Bishop, PR Nowicki, MJ TI Colonic sunflower seed bezoar SO PEDIATRICS LA English DT Article C1 USN,MED CTR,DEPT PEDIAT,DIV PEDIAT GASTROENTEROL & NUTR,PORTSMOUTH,VA 23708. CHILDRENS HOSP KINGS DAUGHTERS,DIV PEDIAT GASTROENTEROL & NUTR,NORFOLK,VA 23507. NR 13 TC 9 Z9 12 U1 0 U2 0 PU AMER ACAD PEDIATRICS PI ELK GROVE VILLAGE PA 141 NORTH-WEST POINT BLVD, ELK GROVE VILLAGE, IL 60007-1098 SN 0031-4005 J9 PEDIATRICS JI Pediatrics PD JUN PY 1997 VL 99 IS 6 BP 896 EP 897 DI 10.1542/peds.99.6.896 PG 2 WC Pediatrics SC Pediatrics GA XC588 UT WOS:A1997XC58800038 PM 9164789 ER PT J AU Swanson, NL VanWinkle, DH AF Swanson, NL VanWinkle, DH TI Forward-scattered light: Spectral broadening and temporal coherence SO PHYSICAL REVIEW A LA English DT Article ID FLUCTUATIONS AB Fabry-Perot spectroscopy was used to observe a spectral broadening of 1.3+/-0.2 MHz in laser light forward scattered through a colloidal solution. Light from a single-mode argon-ion laser was collected after scattering through water to which measured amounts of diatomaceous earth or 0.08-mu m-diam polystyrene spheres were successively added. The broadening is attributed to coupling between fluctuations in particle concentration and spontaneous thermal fluctuations. Though spontaneous fluctuations exist in all pure fluids, they are very weak in water. However, the presence of the particles induces temperature gradients in the fluid, which in turn induce fluctuations in particle concentration. C1 FLORIDA STATE UNIV,CTR MAT RES & TECHNOL,DEPT PHYS,TALLAHASSEE,FL 32306. RP Swanson, NL (reprint author), USN,CTR SURFACE WARFARE,COASTAL SYST STN,DAHLGREN DIV,PANAMA CITY,FL 32407, USA. NR 22 TC 1 Z9 1 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD JUN PY 1997 VL 55 IS 6 BP 4501 EP 4510 DI 10.1103/PhysRevA.55.4501 PG 10 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA XE372 UT WOS:A1997XE37200072 ER PT J AU Golubov, AA Mazin, II AF Golubov, AA Mazin, II TI Effect of magnetic and nonmagnetic impurities on highly anisotropic superconductivity SO PHYSICAL REVIEW B LA English DT Article ID SCATTERING; TC; TRANSPORT; STATE AB We generalize Abrikosov-Gor'kov solution of the problem of weakly coupled superconductors with impurities to the case of a multiband superconductor with arbitrary interband order parameter anisotropy, including interband sign reversal of the order parameter. The solution is given in terms of the effective (renormalized) coupling matrix and describes not only T-c suppression but also renormalization of the superconducting gap basically at all temperatures. In many Limiting cases we find analytical solutions for the critical temperature suppression. We illustrate our results by numerical calculations for two-band model systems. C1 RUSSIAN ACAD SCI,INST SOLID STATE PHYS,CHERNOGOLOVKA 142432,RUSSIA. GEORGE MASON UNIV,WASHINGTON,DC 20375. USN,RES LAB,COMPLEX SYST THEORY BRANCH,WASHINGTON,DC 20375. RP Golubov, AA (reprint author), UNIV TWENTE,DEPT APPL PHYS,POB 217,NL-7500 AE ENSCHEDE,NETHERLANDS. RI Mazin, Igor/B-6576-2008 NR 31 TC 199 Z9 201 U1 1 U2 12 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JUN 1 PY 1997 VL 55 IS 22 BP 15146 EP 15152 DI 10.1103/PhysRevB.55.15146 PG 7 WC Physics, Condensed Matter SC Physics GA XF602 UT WOS:A1997XF60200063 ER PT J AU Jha, SS Rajagopal, AK AF Jha, SS Rajagopal, AK TI Intralayer and interlayer spin-singlet pairing and energy gap functions with different possible symmetries in high-T-c layered superconductors SO PHYSICAL REVIEW B LA English DT Article ID INTERACTING CONDUCTING LAYERS; WAVE SUPERCONDUCTORS; CRITICAL-TEMPERATURE; ORDER-PARAMETER; UNIT-CELL; YBA2CU3O7-DELTA; FLUCTUATIONS; DEPENDENCE; JUNCTIONS; NUMBER AB Anisotropy and the wave-vector dependence of the energy gap function determine many important properties of a superconductor. Stal ting from fist principles, we present here a complete analysis of possible symmetries of the superconducting gap function E-g(k) at the Fermi surface in high-T-c layered superconductors with either a simple orthorhombic or a tetragonal unit cell. This is done within the framework of Gorkov's mean-held theory of superconductivity in the so-called ''layer representation'' introduced by us earlier. For N conducting cuprate layers. J = 1,2,...,N, in each unit cell, the spin-singlet order parameters Delta(JJ')(k) can be expanded in terms of possible basis functions of all the irreducible representations relevant to layered crystals, which are obtained here. In layered materials, the symmetry is restricted to the translational lattice periodicity in the direction perpendicular to the layers and the residual point group and translational symmetries for the two-dimensional unit cell in each layer of the three-dimensional unit cell. We derive an exact general relation to determine different branches of the energy gap function E-g(k) at the Fermi surface in terms of Delta(JJ')(k), which include both intralayer and interlayer order parameters. For N = 2, we also obtain an exact expression for quasiparticle energies E-p(k), p = 1,2. in the superconducting state in the presence of intralayer and complex interlayer order parameters as well as complex tunneling matrix elements between the two layers in the unit cell, which need not be equivalent. The form of the possible basis functions are also listed in terms of cylindrical coordinates k(t),phi,k(z) to take advantage of the orthogonality of functions with respect to phi integrations. In layered materials, with open Fermi surfaces in the k(z) direction, there is orthogonality of basis functions with respect to k(z) also (-pi less than or equal to k(z)d less than or equal to pi). Our results show that in orthorhombic systems, planar d(kx2-ky2)-like (B-1g) and d(kxky)-like (B-2g) symmetries are always mixed, respectively, with the planar s-wave-like (A(1g)) and A(2g)-like symmetries of the corresponding tetragonal system. There is also the possibility of a weak modulation of E-g(k) as a function of k(z)(similar to cos k(z)d). In addition, in the presence of interlayer pairings which may or may not have the same symmetry as the intralayer order parameters, even in tetragonal systems the nodes of the d(kz2-ky2)-like intralayer gap function will be shifted. In view of this, some suggestions for analyzing experimental data are also presented. C1 JAWAHARLAL NEHRU CTR ADV SCI RES,BANGALORE 560064,KARNATAKA,INDIA. USN,RES LAB,WASHINGTON,DC 20375. RP Jha, SS (reprint author), TATA INST FUNDAMENTAL RES,HOMI BHABHA RD,MUMBAI 400005,INDIA. NR 42 TC 8 Z9 8 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JUN 1 PY 1997 VL 55 IS 22 BP 15248 EP 15260 DI 10.1103/PhysRevB.55.15248 PG 13 WC Physics, Condensed Matter SC Physics GA XF602 UT WOS:A1997XF60200074 ER PT J AU Sanford, TWL Nash, TJ Mock, RC Spielman, RB Struve, KW Hammer, JH DeGroot, JS Whitney, KG Apruzese, JP AF Sanford, TWL Nash, TJ Mock, RC Spielman, RB Struve, KW Hammer, JH DeGroot, JS Whitney, KG Apruzese, JP TI Dynamics of a high-power aluminum-wire array Z-pinch implosion SO PHYSICS OF PLASMAS LA English DT Article ID RAYLEIGH-TAYLOR INSTABILITY; MODEL; PLASMAS AB Annular Al-wire Z-pinch implosions on the Saturn accelerator [D.D. Bloomquist et al., Proceedings, 6th Pulsed Power Conference (Institute of Electrical and Electronics Engineers, New York, 1987), p. 310] that have high azimuthal symmetry exhibit both a strong first and weaker second x-ray burst that correlate with strong and weaker radial compressions, respectively. Measurements suggest that the observed magnetic Rayleigh-Taylor (RT) instability prior to the first compression seeds an m=0 instability observed later. Analyses of axially averaged spectral data imply that, during the first compression, the plasma is composed of a hot core surrounded by a cooler plasma halo. Two-dimensional (2-D) radiation magnetohydrodynamic computer simulations show that a RT instability grows to the classic bubble and spike structure during the course of the implosion. The main radiation pulse begins when the bubble reaches the axis and ends when the spike finishes stagnating on axis and the first compression ends. These simulations agree qualitatively with the measured characteristics of the first x-ray pulse and the overall energetics, and they provide a 2-D view into the plasma hydrodynamics of the implosion. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. USN,RES LAB,RADIAT HYDRODYNAM BRANCH,WASHINGTON,DC 20375. RP Sanford, TWL (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 34 TC 52 Z9 54 U1 1 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JUN PY 1997 VL 4 IS 6 BP 2188 EP 2203 DI 10.1063/1.872382 PG 16 WC Physics, Fluids & Plasmas SC Physics GA XB803 UT WOS:A1997XB80300019 ER PT J AU Freund, HP Zaidman, EG AF Freund, HP Zaidman, EG TI Nonlinear theory of collective effects in helix traveling wave tubes SO PHYSICS OF PLASMAS LA English DT Article ID FIELD-THEORY; AMPLIFIER AB A time-dependent collective nonlinear analysis of a helix traveling wave tube including fluctuating (ac) space-charge effects is presented for a configuration where an electron beam propagates through a sheath helix surrounded by a conducting wall. The effects of dielectric and vane loading of the helix are included, as is efficiency enhancement by tapering the helix pitch, and external focusing by means of either a uniform solenoidal magnetic field or a periodic field produced by a periodic permanent magnet stack. Dielectric loading is described under the assumption that the gap between the helix and the wall is uniformly filled by a dielectric material. Vane loading describes the insertion of an arbitrary number of vanes running the length of the helix. The electromagnetic field is represented as a superposition of azimuthally symmetric waves in a vacuum sheath helix. The propagation of each wave in vacuo, as well as the interaction of each wave with the electron beam, is included by allowing the amplitudes of the waves to vary in z and t. The dynamical equation for the field is solved in conjunction with the three-dimensional Lorentz force equations for an ensemble of electrons. Collective effects from the fluctuating rf beam space-charge waves are also included in the analysis by means of a superposition of solutions of the Helmholtz equation. The simulation is compared with a linear theory of the interaction, and an example is described corresponding to a tube built at Northrop-Grumman Corp. (C) 1997 American Institute of Physics. C1 SCI APPLICAT INT CORP,MCLEAN,VA 22102. RP Freund, HP (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 19 TC 21 Z9 23 U1 1 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JUN PY 1997 VL 4 IS 6 BP 2292 EP 2301 DI 10.1063/1.872393 PG 10 WC Physics, Fluids & Plasmas SC Physics GA XB803 UT WOS:A1997XB80300032 ER PT J AU Maurer, JH AF Maurer, JH TI Arms control and the Anglo-German naval race before World War I: Lessons for today? SO POLITICAL SCIENCE QUARTERLY LA English DT Article ID COOPERATION RP Maurer, JH (reprint author), USN,WAR COLL,WASHINGTON,DC, USA. NR 44 TC 0 Z9 0 U1 0 U2 1 PU ACAD POLITICAL SCIENCE PI NEW YORK PA 475 RIVERSIDE DRIVE, SUITE 1274, NEW YORK, NY 10115-1274 SN 0032-3195 J9 POLIT SCI QUART JI Polit. Sci. Q. PD SUM PY 1997 VL 112 IS 2 BP 285 EP 306 DI 10.2307/2657942 PG 22 WC Political Science SC Government & Law GA XQ828 UT WOS:A1997XQ82800006 ER PT J AU Catalano, G Catalano, MC Sheehan, KH Stock, SL Alberts, VA AF Catalano, G Catalano, MC Sheehan, KH Stock, SL Alberts, VA TI A survey of United States general psychiatry residency programs: Program characteristics and relationship to the 1994 National Residency Matching Program results SO PSYCHIATRIC QUARTERLY LA English DT Article ID CHOICE AB We developed a questionnaire regarding issues in psychiatric residency training and distributed it to the chief residents at all United States general psychiatry residency training programs. We hoped to examine psychiatry residency program characteristics and see if any particular characteristics had a significant relationship to improved success in the 1994 National Residency Matching Program (NRMP) results. We found that those programs with six or more PGY-1 positions available in the NRMP, those programs with an associated child and adolescent psychiatry residency training program, and those programs offering a research elective had a higher PGY-1 match through the NRMP than programs without these features. C1 UNIV S FLORIDA,COLL MED,DEPT PSYCHIAT & BEHAV MED,TAMPA,FL. JAMES A HALEY VET HOSP,PSYCHIAT SERV,TAMPA,FL 33612. USN,MED CTR,DEPT PSYCHIAT,SAN DIEGO,CA 92152. NR 9 TC 5 Z9 5 U1 0 U2 0 PU HUMAN SCI PRESS INC PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013-1578 SN 0033-2720 J9 PSYCHIAT QUART JI Psychiatr. Q. PD SUM PY 1997 VL 68 IS 2 BP 167 EP 185 DI 10.1023/A:1025457706039 PG 19 WC Psychiatry SC Psychiatry GA WU572 UT WOS:A1997WU57200006 PM 9114472 ER PT J AU Leach, MJ Raman, S Mohanty, UC Madala, RV AF Leach, MJ Raman, S Mohanty, UC Madala, RV TI The role of radiative transfer in maintaining the Indian summer monsoon circulation SO PURE AND APPLIED GEOPHYSICS LA English DT Article DE atmospheric radiative transfer; circulation; Indian summer monsoon; thermal forcing ID MODEL; PARAMETERIZATION; SCHEMES AB The radiative-convective feedback and land-sea thermal forcing play significant roles in maintenance of the summer monsoon circulation over the Indian sub-continent. In this study, the role of radiative transfer in maintaining the monsoon circulation is examined with numerical sensitivity experiments. For this purpose, a sixteen layer primitive equation limited area model is used to perform numerical simulations with and without atmospheric radiative transfer processes parameterized in the model. The initial values and boundary conditions for the numerical integrations of the model are derived from operational analyses of the ECMWF, UK. The results show that the radiative transfer is essential in maintaining the intensity of the low level Somali Jet as well as the upper level Tropical Easterly Jet (TEJ) over the Indian sub-continent and adjoining seas. The meridional circulation over the neon is also well simulated. As a result, enough moisture transports from the warm equatorial region to simulate more realistic orographic precipitation in the windward side of the mountains along the West coast of India. Without radiative transfer processes in the model atmosphere the simulated monsoon circulation weakens, moisture transport decreases and the precipitation lessens. C1 Indian Inst Technol DELHI, CTR ATMOSPHER SCI, NEW DELHI, INDIA. USN, RES LAB, WASHINGTON, DC 20375 USA. RP Leach, MJ (reprint author), N CAROLINA STATE UNIV, DEPT MARINE EARTH & ATMOSPHER SCI, BOX 8208, RALEIGH, NC 27695 USA. NR 14 TC 0 Z9 0 U1 0 U2 1 PU BIRKHAUSER VERLAG AG PI BASEL PA VIADUKSTRASSE 40-44, PO BOX 133, CH-4010 BASEL, SWITZERLAND SN 0033-4553 J9 PURE APPL GEOPHYS JI Pure Appl. Geophys. PD JUN PY 1997 VL 149 IS 3 BP 601 EP 622 DI 10.1007/s000240050043 PG 22 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA XH014 UT WOS:A1997XH01400009 ER PT J AU Sethian, JD Obenschain, SP Gerber, KA Pawley, CJ Serlin, V Sullivan, CA Webster, W Deniz, AV Lehecka, T McGeoch, MW Altes, RA Corcoran, PA Smith, ID Barr, OC AF Sethian, JD Obenschain, SP Gerber, KA Pawley, CJ Serlin, V Sullivan, CA Webster, W Deniz, AV Lehecka, T McGeoch, MW Altes, RA Corcoran, PA Smith, ID Barr, OC TI Large area electron beam pumped krypton fluoride laser amplifier SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID INERTIAL CONFINEMENT FUSION; KRF LASERS; PERFORMANCE AB Nike is a recently completed multi-kilojoule krypton fluoride (KrF) laser that has been built to study the physics of direct drive inertial confinement fusion. This paper describes in detail both the pulsed power and optical performance of the largest amplifier in the Nike laser, the 60 cm amplifier. This is a double pass, double sided, electron beam-pumped system that amplifies the laser beam from an input of 50 J to an output of up to 5 kJ. It has an optical aperture of 60 cm x 60 cm and a gain length of 200 cm. The two electron beams are 60 cm high x 200 cm wide, have a voltage of 640 kV, a current of 540 kA, and a flat top power pulse duration of 250 ns. A 2 kG magnetic field is used to guide the beams and prevent self-pinching. Each electron beam is produced by its own Marx/pulse forming line system. The amplifier has been fully integrated into the Nike system and is used on a daily basis for laser-target experiments. (C) 1997 American Institute of Physics. C1 RES SUPPORT INSTRUMENTS,LANHAM,MD 20706. SCI APPLICAT INT CORP,MCLEAN,VA 22102. PLEX CORP,BROOKLINE,MA 02146. PULSE SCI INC,SAN LEANDRO,CA 94577. PHAROS TECH ENTERPRISES,LIVERMORE,CA 94550. RP Sethian, JD (reprint author), USN,RES LAB,DIV PLASMA PHYS,WASHINGTON,DC 20375, USA. NR 31 TC 41 Z9 44 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JUN PY 1997 VL 68 IS 6 BP 2357 EP 2366 DI 10.1063/1.1148118 PG 10 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA XF624 UT WOS:A1997XF62400018 ER PT J AU Pao, PS Meyn, DA Bayles, RA Feng, CR Yoder, GR AF Pao, PS Meyn, DA Bayles, RA Feng, CR Yoder, GR TI On ripple-load, stress-corrosion, and sustained-load cracking behavior in a high strength beta titanium alloy SO SCRIPTA MATERIALIA LA English DT Article C1 OFF NAVAL RES,ARLINGTON,VA 22217. RP Pao, PS (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 14 TC 1 Z9 1 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD JUN 1 PY 1997 VL 36 IS 11 BP 1321 EP 1326 DI 10.1016/S1359-6462(96)00490-3 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA WZ266 UT WOS:A1997WZ26600018 ER PT J AU Spikes, CH Erskine, FT McEachern, JF Backes, DA AF Spikes, CH Erskine, FT McEachern, JF Backes, DA TI Littoral warfare technology testing SO SEA TECHNOLOGY LA English DT Article C1 USN,RES LAB,WASHINGTON,DC 20375. USN,AIR WARFARE CTR,DIV AIRCRAFT,PATUXENT RIVER,MD. RP Spikes, CH (reprint author), MARINE ACOUST INC,ARLINGTON,VA, USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU COMPASS PUBL INC PI ARLINGTON PA SUITE 1000 1117 N 19 ST, ARLINGTON, VA 22209 SN 0093-3651 J9 SEA TECHNOL JI Sea Technol. PD JUN PY 1997 VL 38 IS 6 BP 71 EP & PG 5 WC Engineering, Ocean SC Engineering GA XG284 UT WOS:A1997XG28400014 ER PT J AU Cho, S DiVenere, A Wong, GK Ketterson, JB Meyer, JR Hoffman, CA AF Cho, S DiVenere, A Wong, GK Ketterson, JB Meyer, JR Hoffman, CA TI Thermoelectric power of MBE grown Bi thin films and BI/CDTE superlattices on CdTe substrates SO SOLID STATE COMMUNICATIONS LA English DT Article ID MOLECULAR-BEAM EPITAXY; PBTE-BI; FIGURE; MERIT AB We have measured the thermoelectric power (TEP) of epitaxial Bi thin films and Bi/CdTe superlattices grown on CdTe substrates as a function of temperature in the range 20-300 K. We have observed that the TEP of a 10000 Angstrom A Bi thin film is in good agreement with the bulk single crystal value and that the TEPs for superlattices with 400 Angstrom A and 800 Angstrom A Bi well thicknesses are enhanced over the bulk values. However, p-type doping effects in both thin films and superlattices lead to a positive TEP in samples with thinner quantum wells and a suppression of the magnitude in all cases. This suggests that the TEP may be enhanced further by altering the growth conditions to reduce the excess hole concentration. (C) 1997 Published by Elsevier Science Ltd. C1 USN,RES LAB,WASHINGTON,DC 20375. DEPT ELECT & COMP ENGN,URBANA,IL. RP Cho, S (reprint author), NORTHWESTERN UNIV,DEPT PHYS & ASTRON,EVANSTON,IL 60208, USA. RI Ketterson, John/B-7234-2009 NR 20 TC 25 Z9 26 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0038-1098 J9 SOLID STATE COMMUN JI Solid State Commun. PD JUN PY 1997 VL 102 IS 9 BP 673 EP 676 DI 10.1016/S0038-1098(97)00063-X PG 4 WC Physics, Condensed Matter SC Physics GA WX403 UT WOS:A1997WX40300008 ER PT J AU Lima, ICD Weber, G Reinecke, TL AF Lima, ICD Weber, G Reinecke, TL TI Gamma-X hybridization effects on the carrier subband transition times in type I GaAs-AlAs quantum wells SO SOLID STATE COMMUNICATIONS LA English DT Article ID SHORT-PERIOD SUPERLATTICES; PHONON SCATTERING RATES; SPACE CHARGE-TRANSFER; ENVELOPE FUNCTIONS; SEMICONDUCTOR HETEROINTERFACES; CONFINED PHONONS; BINDING-ENERGY; GAAS/ALAS; CONNECTION; EMISSION AB We calculate the Gamma - Gamma carrier scattering times due to emission of confined and interface optic phonons taking into account the Gamma-X hybridization of the electron states for type I GaAs/AlAs quantum well structures. We show that the intersubband transition times increase for well widths where the second GaAs electron subband becomes dose in energy to the X point of the AlAs barrier and that this increase is strongly dependent on the amount of hybridization. These results suggests that the hybridization may affect carrier transport and relaxation and that intersubband scattering times could be used for measuring the hybridization of the second electron subband. (C) 1997 Elsevier Science Ltd. C1 UNIV ESTADO RIO DE JANEIRO,INST FIS,BR-20550013 RIO JANEIRO,BRAZIL. USN,RES LAB,WASHINGTON,DC 20375. RP Lima, ICD (reprint author), UNIV SAO FRANCISCO,FAC ENGN,BR-13251900 ITATIBA,SP,BRAZIL. RI Weber, Gerald/A-8669-2010 OI Weber, Gerald/0000-0002-2935-1571 NR 23 TC 2 Z9 2 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0038-1098 J9 SOLID STATE COMMUN JI Solid State Commun. PD JUN PY 1997 VL 102 IS 11 BP 799 EP 802 PG 4 WC Physics, Condensed Matter SC Physics GA XA614 UT WOS:A1997XA61400006 ER PT J AU Davis, TA Black, AT Lee, KP AF Davis, TA Black, AT Lee, KP TI Soluble factor(s) alone produced by primary porcine microvascular endothelial cells support the proliferation and differentiation of human CD34(+) hematopoietic progenitor cells with a high replating potential SO TRANSPLANTATION PROCEEDINGS LA English DT Article; Proceedings Paper CT International Congress of the Transplant-Society CY SEP 29-OCT 02, 1996 CL MIAMI BEACH, FL SP Transplantat Soc C1 UNIFORMED SERV UNIV HLTH SCI,BETHESDA,MD 20814. RP Davis, TA (reprint author), USN,MED RES INST,IMMUNE CELL BIOL PROGRAM,STEM CELL BIOL BRANCH,BLDG 18,ROOM 230,BETHESDA,MD 20889, USA. NR 5 TC 3 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0041-1345 J9 TRANSPLANT P JI Transplant. Proc. PD JUN PY 1997 VL 29 IS 4 BP 2003 EP 2004 DI 10.1016/S0041-1345(97)00205-4 PG 2 WC Immunology; Surgery; Transplantation SC Immunology; Surgery; Transplantation GA XE833 UT WOS:A1997XE83300045 PM 9193500 ER PT J AU Davis, TA Lee, KP AF Davis, TA Lee, KP TI Ex vivo expansion of primitive murine hematopoietic progenitor cells on porcine endothelial coils SO TRANSPLANTATION PROCEEDINGS LA English DT Article; Proceedings Paper CT International Congress of the Transplant-Society CY SEP 29-OCT 02, 1996 CL MIAMI BEACH, FL SP Transplantat Soc C1 UNIFORMED SERV UNIV HLTH SCI,BETHESDA,MD 20814. RP Davis, TA (reprint author), USN,MED RES INST,IMMUNE CELL BIOL PROGRAM,STEM CELL BIOL BRANCH,BLDG 18,ROOM 230,BETHESDA,MD 20889, USA. NR 5 TC 3 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0041-1345 J9 TRANSPLANT P JI Transplant. Proc. PD JUN PY 1997 VL 29 IS 4 BP 2005 EP 2005 DI 10.1016/S0041-1345(97)00206-6 PG 1 WC Immunology; Surgery; Transplantation SC Immunology; Surgery; Transplantation GA XE833 UT WOS:A1997XE83300046 PM 9193501 ER PT J AU Levine, BL Bernstein, W Craighead, N Thompson, CB Lindsten, T StLouis, DC June, CH AF Levine, BL Bernstein, W Craighead, N Thompson, CB Lindsten, T StLouis, DC June, CH TI Ex vivo replicative potential of adult human peripheral blood CD4+ T cells SO TRANSPLANTATION PROCEEDINGS LA English DT Article; Proceedings Paper CT International Congress of the Transplant-Society CY SEP 29-OCT 02, 1996 CL MIAMI BEACH, FL SP Transplantat Soc C1 WALTER REED ARMY INST RES,DIV RETROVIROL,ROCKVILLE,MD. HENRY M JACKSON FDN ADVANCEMENT MIL MED,ROCKVILLE,MD. GWEN KNAPP CTR,CHICAGO,IL. RP Levine, BL (reprint author), USN,MED RES INST,BETHESDA,MD 20889, USA. RI Levine, Bruce/D-1688-2009 NR 0 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0041-1345 J9 TRANSPLANT P JI Transplant. Proc. PD JUN PY 1997 VL 29 IS 4 BP 2028 EP 2028 DI 10.1016/S0041-1345(97)00216-9 PG 1 WC Immunology; Surgery; Transplantation SC Immunology; Surgery; Transplantation GA XE833 UT WOS:A1997XE83300056 PM 9193511 ER PT J AU Joye, DD Wechgelaer, P AF Joye, DD Wechgelaer, P TI Simulating respiratory loads and tuning of closed-circuit underwater breathing apparatus SO UNDERSEA & HYPERBARIC MEDICINE LA English DT Article DE elastance; inertance; mathematical model; experimentally simulated; underwater breathing apparatus AB An experimental apparatus for simulating respiratory loads in closed-circuit underwater breathing systems comprises a partly submerged vertical tube having a dual path exit on the submerged end of the tube. One path is controlled by a valve that alters the inertance of the system, changes the natural frequency, and provides the tuning. The vertical tube provides elastic loading to simulate a counterlung or breathing bag in an underwater breathing apparatus (UBA). The experimental apparatus was connected to a breathing machine controlled by a signal generator to simulate a diver's breathing. The benefits of reactance tuning of this apparatus are demonstrated. A mathematical model describes both the simulator and UBA. The simulator can be used with human subjects to study respiratory response to changes in impedance. C1 USN,MED RES INST,BETHESDA,MD 20889. UNIFORMED SERV UNIV HLTH SCI,BETHESDA,MD 20814. NR 12 TC 2 Z9 2 U1 0 U2 0 PU UNDERSEA & HYPERBARIC MEDICAL SOC INC PI KENSINGTON PA 10531 METROPOLITAN AVE, KENSINGTON, MD 20895 SN 1066-2936 J9 UNDERSEA HYPERBAR M JI Undersea Hyperb. Med. PD JUN PY 1997 VL 24 IS 2 BP 81 EP 89 PG 9 WC Marine & Freshwater Biology; Medicine, Research & Experimental SC Marine & Freshwater Biology; Research & Experimental Medicine GA XA833 UT WOS:A1997XA83300005 PM 9171467 ER PT J AU Fothergill, DM Joye, DD Carlson, NA AF Fothergill, DM Joye, DD Carlson, NA TI Diver respiratory responses to a tunable closed-circuit breathing apparatus SO UNDERSEA & HYPERBARIC MEDICINE LA English DT Article DE diving; closed-circuit breathing apparatus; elastance; inertance; breathing impedance; respiratory effort ID BORG SCALE; EXERCISE; DYSPNEA; BREATHLESSNESS AB Respiratory impedance of closed-circuit underwater breathing apparatus (UBA) is comprised of resistive, elastic, and inertial elements in series. Impedance is at a minimum when a UBA operates at its resonant frequency (f(n)). This study investigated the respiratory responses of 12 male U.S. Navy divers to changes in the f(n) of a simulated closed-circuit UBA. Respiratory effort, breathing comfort and ventilatory parameters were assessed during open- and closed-circuit breathing at rest and while exercising at 75 W on a bicycle ergometer in the dry at 1 atm abs. During closed-circuit breathing, the f(n) of the system was adjusted to different frequencies between 0.2 Hz and 0.4 Hz (12 and 24 breaths/min) by varying UBA inertance. When the simulated UBA was switched from open to closed-circuit breathing the subjects changed their breathing frequency in a direction toward the f(n) of the system and attempted to maintain minute ventilation constant by adjusting tidal volume. Results suggest that when divers breathe on a closed-circuit system with different f(n)'s they attempt to improve breathing comfort and reduce respiratory effort by adopting a breathing pattern that reduces their peak-to-peak mouth pressures. C1 VILLANOVA UNIV,DEPT CHEM ENGN,VILLANOVA,PA 19085. USN,SUBMARINE MED RES LAB,NAVAL SUBMARINE BASE NEW LONDON,GROTON,CT 06349. RP Fothergill, DM (reprint author), USN,MED RES INST,8901 WISCONSIN AVE,BETHESDA,MD 20889, USA. NR 18 TC 4 Z9 4 U1 0 U2 0 PU UNDERSEA & HYPERBARIC MEDICAL SOC INC PI KENSINGTON PA 10531 METROPOLITAN AVE, KENSINGTON, MD 20895 SN 1066-2936 J9 UNDERSEA HYPERBAR M JI Undersea Hyperb. Med. PD JUN PY 1997 VL 24 IS 2 BP 91 EP 105 PG 15 WC Marine & Freshwater Biology; Medicine, Research & Experimental SC Marine & Freshwater Biology; Research & Experimental Medicine GA XA833 UT WOS:A1997XA83300006 PM 9171468 ER PT J AU Walker, CJ Kaplan, GW Cilento, BG AF Walker, CJ Kaplan, GW Cilento, BG TI Clinical and radiologic findings in schistosomiasis of the bladder SO UROLOGY LA English DT Article C1 USN,REG MED CTR,DEPT UROL,SAN DIEGO,CA 92134. UNIV CALIF SAN DIEGO,SAN DIEGO MED CTR,DIV UROL,SAN DIEGO,CA 92103. CHILDRENS HOSP & HLTH CTR,SAN DIEGO,CA. NR 2 TC 1 Z9 1 U1 0 U2 0 PU CAHNERS PUBL CO PI NEW YORK PA 249 WEST 17 STREET, NEW YORK, NY 10011 SN 0090-4295 J9 UROLOGY JI UROLOGY PD JUN PY 1997 VL 49 IS 6 BP 951 EP 952 DI 10.1016/S0090-4295(97)00097-6 PG 2 WC Urology & Nephrology SC Urology & Nephrology GA XC721 UT WOS:A1997XC72100029 PM 9187708 ER PT J AU Hoffman, SL Doolan, DL Sedegah, M Aguiar, JC Wang, RB Malik, A Gramzinski, RA Weiss, WR Hobart, P Norman, JA Margalith, M Hedstrom, RC AF Hoffman, SL Doolan, DL Sedegah, M Aguiar, JC Wang, RB Malik, A Gramzinski, RA Weiss, WR Hobart, P Norman, JA Margalith, M Hedstrom, RC TI Strategy for development of a pre-erythrocytic Plasmodium falciparum DNA vaccine for human use SO VACCINE LA English DT Article; Proceedings Paper CT International Meeting on Nucleic Acid Vaccines for the Prevention of Infectious Diseases CY FEB 05-07, 1996 CL BETHESDA, MD SP European Commiss, US FDA, Nat Inst Allergy & Infect Dis, WHO DE DNA vaccine; malaria; pre-erythrocytic stage ID SPOROZOITE SURFACE PROTEIN-2; PROTECTION; MALARIA; YOELII AB Data generated in the Plasmodium yoelii rodent model indicated that plasmid DNA vaccines encoding the P. yoelii circumsporozoite protein (PyCSP) or 17 kDa hepatocyte erythrocyte protein (PyHEP17) were potent inducers of protective CD8(+) T cell responses directed against infected hepatocytes. Immunization with a mixture of these plasmids circumvented the genetic restriction of protective immunity and induced additive protection. A third DNA vaccine encoding the P. yoelii sporozoite surface protein 2 (PySSP2) also induced protection. The P. falciparum genes encoding the homologues of these three protective P. yoelii antigens as well as another P. falciparum gene encoding a protein that is expressed in infected hepatocytes have been chosen for the development of a human vaccine. The optimal plasmid constructs for human use will be selected on the basis of immunogenicity data generated in mice and nonhuman primates. We anticipate that optimization of multi-gene P. falciparum DNA vaccines designed to protect against malaria by inducing CD8(+) cells that target infected hepatocytes will require extensive clinical trials during the coming years. Published by Elsevier Science Ltd. C1 VICAL INC,SAN DIEGO,CA 92121. RP Hoffman, SL (reprint author), USN,MED RES INST,MALARIA PROGRAM,BETHESDA,MD 20889, USA. RI Doolan, Denise/F-1969-2015 NR 10 TC 36 Z9 36 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0264-410X J9 VACCINE JI Vaccine PD JUN PY 1997 VL 15 IS 8 BP 842 EP 845 DI 10.1016/S0264-410X(96)00273-3 PG 4 WC Immunology; Medicine, Research & Experimental SC Immunology; Research & Experimental Medicine GA XJ336 UT WOS:A1997XJ33600018 PM 9234529 ER PT J AU Gramzinski, RA Maris, DC Doolan, D Charoenvit, Y Obaldia, N Rossan, R Sedegah, M Wang, RB Hobart, P Margalith, M Hoffman, S AF Gramzinski, RA Maris, DC Doolan, D Charoenvit, Y Obaldia, N Rossan, R Sedegah, M Wang, RB Hobart, P Margalith, M Hoffman, S TI Malaria DNA vaccines in Aotus monkeys SO VACCINE LA English DT Article; Proceedings Paper CT International Meeting on Nucleic Acid Vaccines for the Prevention of Infectious Diseases CY FEB 05-07, 1996 CL BETHESDA, MD SP European Commiss, US FDA, Nat Inst Allergy & Infect Dis, WHO DE DNA vaccine; malaria; monkeys; Aotus; antibody ID PLASMODIUM-FALCIPARUM; CIRCUMSPOROZOITE PROTEIN; EXPERIMENTAL INFECTION; SUSCEPTIBILITY; IMMUNIZATION; TRIVIRGATUS AB In preparation for the development of DNA vaccines designed to produce protective antibodies against Plasmodium falciparum antigens (Ag), we conducted studies to optimize antibody responses in Aotus monkeys after immunization with the P. yoelli circumsporozoite (CSP) DNA vaccine. We demonstrate in Aotus monkeys that an intradermal route of immunization with a PyCSP plasmid DNA vaccine generates antibody responses equivalent to a multiple antigen peptide/adjuvant-based vaccine, and that these data support the use of the intradermal route for initial studies of the efficacy of DNA vaccines in inducing protective antibodies against P. falciparum antigens in Aotus monkeys. (C) 1997 Elsevier Science Ltd. C1 USN,MED RES INST,MALARIA PROGRAM,BETHESDA,MD 20814. GORGAS MEM LAB,PANAMA CITY,PANAMA. PROMED INC,PANAMA CITY,PANAMA. VIRAL INC,SAN DIEGO,CA. RI Doolan, Denise/F-1969-2015; Obaldia, Nicanor/O-8460-2015; OI Obaldia, Nicanor/0000-0002-3711-9449 NR 21 TC 38 Z9 38 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0264-410X J9 VACCINE JI Vaccine PD JUN PY 1997 VL 15 IS 8 BP 913 EP 915 DI 10.1016/S0264-410X(96)00270-8 PG 3 WC Immunology; Medicine, Research & Experimental SC Immunology; Research & Experimental Medicine GA XJ336 UT WOS:A1997XJ33600035 PM 9234546 ER PT J AU Brower, JB Barford, CC AF Brower, JB Barford, CC TI Biological fixed-film systems SO WATER ENVIRONMENT RESEARCH LA English DT Review C1 HARVARD UNIV,DIV ENGN & APPL SCI,CAMBRIDGE,MA 02138. RP Brower, JB (reprint author), USN,RES LAB,CODE 6900,4555 OVERLOOK AVE,WASHINGTON,DC 20375, USA. NR 175 TC 4 Z9 4 U1 0 U2 2 PU WATER ENVIRONMENT FEDERATION PI ALEXANDRIA PA 601 WYTHE ST, ALEXANDRIA, VA 22314-1994 SN 1061-4303 J9 WATER ENVIRON RES JI Water Environ. Res. PD JUN PY 1997 VL 69 IS 4 BP 487 EP 500 DI 10.2175/106143097X134795 PG 14 WC Engineering, Environmental; Environmental Sciences; Limnology; Water Resources SC Engineering; Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA XH757 UT WOS:A1997XH75700010 ER PT J AU Hirschberg, PA Parke, MC Wash, CH Mickelinc, M Spencer, RW Thaler, E AF Hirschberg, PA Parke, MC Wash, CH Mickelinc, M Spencer, RW Thaler, E TI The usefulness of MSU3 analyses as a forecasting aid: A statistical study SO WEATHER AND FORECASTING LA English DT Article ID EXTRATROPICAL CYCLONES; TROPOPAUSE UNDULATIONS; HEIGHT TENDENCY; ANALYTIC MODEL; UNITED-STATES; CYCLOGENESIS; CIRCULATION; DIAGNOSIS; VORTICITY; ANOMALIES AB A statistical analysis is performed on a 6-month global dataset consisting of satellite-derived channel 3 Microwave Sounding Unit (MSU3) brightness temperature and various conventionally derived fields to quantify the potential usefulness of MSU3 analyses in the nowcasting and forecasting of baroclinic waves. High positive spatial and temporal correlations are obtained between the MSU3 brightness temperature and 400-100-mb thickness fields over all wavelengths in the data. Slightly lesser positive correlations are found between the MSU3 and the 200-mb temperature. The MSU3-500-mb and MSU3-50-mb height correlation results indicate a scale dependence in the hydrostatic spreading of thickness anomalies in the vertical, Most significantly, relatively high negative MSU3-500-mb height correlations for the short (less than or equal to synoptic scale) wavelength portion of the data suggest that upper-level thermal anomalies are reflected downward and that MSU3 analyses can be used to track midlevel synoptic-scale baroclinic waves. This conclusion is also supported by relatively high negative MSU3-500-mb vorticity and MSU3-dynamic tropopause correlations along the climatological storm tracks. C1 USN,POSTGRAD SCH,DEPT METEOROL,MONTEREY,CA 93943. NASA,GEORGE C MARSHALL SPACE FLIGHT CTR,EARTH SYST SCI DIV,HUNTSVILLE,AL 35812. NATL WEATHER SERV,DENVER,CO. NR 34 TC 3 Z9 3 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0882-8156 J9 WEATHER FORECAST JI Weather Forecast. PD JUN PY 1997 VL 12 IS 2 BP 324 EP 346 DI 10.1175/1520-0434(1997)012<0324:TUOMAA>2.0.CO;2 PG 23 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA XF203 UT WOS:A1997XF20300008 ER PT J AU Ngai, KL Roland, CM AF Ngai, KL Roland, CM TI Short-time relaxational dynamics of the ''strong'' glass-former methanol SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID DEPOLARIZED-LIGHT-SCATTERING; MOLECULAR-DYNAMICS; NEUTRON-SCATTERING; STRUCTURAL RELAXATION; LIQUIDS; TRANSITION; TERPHENYL; BEHAVIOR; GLYCEROL; POLYMERS AB According to the coupling model of relaxation, structural relaxation in glass-forming liquids is comprised of an intermolecularly uncorrelated step (''fast alpha-relaxation process'') in the picosecond time range followed by a slowed, intermolecularly cooperative, ''slow alpha'' process. Molecular dynamics simulation data [Sindzingre, P.; Klein, M. J. Chem. Phys. 1992, 96, 4681] have shown that for the ''strong'' liquid methanol, the fast relaxation step is absent. This finding is in contrast to the prominent fast relaxation appearing hi fragile liquids about the glass transition temperature. The differing behavior of methanol can be accounted for from an analysis of the self part of the intermediate scattering function, F-s(k,t) according to the coupling model. The latter relates the magnitude of the fast alpha-relaxation to the relaxation time, tau*, and to the exponent beta of the slow ct-process described by the stretched exponential function exp[-(t/tau*)(beta)]. This function fits the experimental Fs(k,t) for t longer than 2 ps, The apparent absence of a fast relaxation step in methanol is shown to be a consequence of the weak intermolecular constraints governing the dynamics in ''strong'' liquids, a result consistent with the prominence of the fast process in polymers and other fragile glass-formers. This conclusion is supported by dielectric relaxation data (frequencies up to 90 GHz) and far-infrared data (> 150 GHz) on methanol. RP Ngai, KL (reprint author), USN, RES LAB, WASHINGTON, DC 20375 USA. NR 47 TC 11 Z9 11 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD MAY 29 PY 1997 VL 101 IS 22 BP 4437 EP 4441 DI 10.1021/jp963352u PG 5 WC Chemistry, Physical SC Chemistry GA XB801 UT WOS:A1997XB80100012 ER PT J AU Pell, JW Auyeung, RCY Chrisey, DB zurLoye, HC AF Pell, JW Auyeung, RCY Chrisey, DB zurLoye, HC TI Laser deposition of oriented BiMeVOx films SO THIN SOLID FILMS LA English DT Article DE laser ablation; oxides; scanning electron microscopy; solid electrolyte interface ID THIN-FILMS; ELECTROLYTES; CONDUCTIVITY; SERIES AB The oxygen-ion conducting ceramics Bi2VO5.5 and Bi2Cu0.1V0.9O5.35 were synthesized and deposited on several substrates by the pulsed laser deposition technique. Defect-free films of Bi2Cu0.1V0.9O5.35 were obtained on SrTiO3 substrates, while films of Bi2VO5.5 exhibited severe cracking. Reasons for the different results are discussed. (C) 1997 Elsevier Science S.A. C1 MIT,DEPT CHEM,CAMBRIDGE,MA 02139. SFA INC,LARGO,MD 20774. USN,RES LAB,WASHINGTON,DC 20375. OI zur Loye, Hans-Conrad/0000-0001-7351-9098 NR 22 TC 11 Z9 13 U1 0 U2 3 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD MAY 28 PY 1997 VL 300 IS 1-2 BP 154 EP 158 DI 10.1016/S0040-6090(96)09559-4 PG 5 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA XH763 UT WOS:A1997XH76300023 ER PT J AU Broido, DA Reinecke, TL AF Broido, DA Reinecke, TL TI Thermoelectric transport in quantum well superlattices SO APPLIED PHYSICS LETTERS LA English DT Article ID PHONON-SCATTERING; HIGH FIGURE; MERIT; MOBILITY; GAP AB A full theory of thermoelectric transport in superlattices, including the well width and energy dependence of the optical and acoustic phonon scattering and the effects of confinement in raising valley degeneracy is developed. It is shown that these features result in qualitatively significant modifications in the predicted figure of merit of superlattice systems. Results are given for PbTe superlattices, and comments are made on recent experimental results for such systems. (C) 1997 American Institute of Physics. C1 USN,RES LAB,WASHINGTON,DC 20375. RP Broido, DA (reprint author), BOSTON COLL,DEPT PHYS,CHESTNUT HILL,MA 02167, USA. NR 22 TC 56 Z9 60 U1 2 U2 18 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAY 26 PY 1997 VL 70 IS 21 BP 2834 EP 2836 DI 10.1063/1.119018 PG 3 WC Physics, Applied SC Physics GA XA599 UT WOS:A1997XA59900019 ER PT J AU Krushelnick, K Ting, A Moore, CI Burris, HR Esarey, E Sprangle, P Baine, M AF Krushelnick, K Ting, A Moore, CI Burris, HR Esarey, E Sprangle, P Baine, M TI Plasma channel formation and guiding during high intensity short pulse laser plasma experiments SO PHYSICAL REVIEW LETTERS LA English DT Article ID 2ND-HARMONIC EMISSION; UNDERDENSE PLASMA; IONIZED PLASMAS; TERAWATT LASER; PROPAGATION; RADIATION; LIGHT AB A plasma channel is formed behind a self-guided, subpicosecond, 2 TW laser pulse in a hydrogen gas jet plasma. The channel is produced from the radial expulsion of plasma ions due to charge separation created in the displacement (or cavitation) of plasma electrons by the large ponderomotive force of the laser. Using Thomson scattering diagnostics and mode structure measurements, an intense trailing laser pulse (I similar to 5 x 10(16) W/cm(2)) is observed to be guided throughout the length of this channel for about 20 Rayleigh lengths, approximately equal to the propagation length of the self-guided pump laser pulse. C1 USN,RES LAB,DIV PLASMA PHYS,WASHINGTON,DC 20375. UNIV CALIF SAN DIEGO,LA JOLLA,CA 92093. RP Krushelnick, K (reprint author), CORNELL UNIV,PLASMA STUDIES LAB,ITHACA,NY 14853, USA. NR 28 TC 182 Z9 185 U1 0 U2 8 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAY 26 PY 1997 VL 78 IS 21 BP 4047 EP 4050 DI 10.1103/PhysRevLett.78.4047 PG 4 WC Physics, Multidisciplinary SC Physics GA XA465 UT WOS:A1997XA46500017 ER PT J AU Brown, SW Kennedy, TA Glaser, ER Katzer, DS AF Brown, SW Kennedy, TA Glaser, ER Katzer, DS TI Optical NMR from single GaAs/AlGaAs quantum wells SO JOURNAL OF PHYSICS D-APPLIED PHYSICS LA English DT Article; Proceedings Paper CT Material-Research-Society Symposium on the Spectroscopy of Heterojunctions CY 1995 CL BOSTON, MA SP Mat Res Soc ID NUCLEAR-MAGNETIC-RESONANCE AB In this work, results of detailed optical nuclear magnetic resonance (ONMR) studies of a series of five single GaAs/AlGaAs quantum wells centre-doped with beryllium are presented. Signals from As-75, Ga-69 and Ga-71 nuclei were clearly observed from single quantum wells with widths ranging from 42 to 143 Angstrom. The Al-27 resonance from the AlGaAs barrier layers was not observed, confirming that the ONMR signal originated within the individual quantum wells. De-polarization of excitonic luminescence from a 60 Angstrom wide quantum well of up to 70% was observed under conditions of adiabatic fast passage through the As-75 resonance. The signal originated from approximately 10-11 nuclei and represents an increase in sensitivity over conventional NMR of 5-6 orders of magnitude. Through studies of effects of optical power, RF power and external magnetic field on the ONMR signal, this work establishes and extends the range of experimental conditions suitable for ONMR in GaAs-based structures. RP Brown, SW (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. RI Katzer, D. Scott/N-7841-2013 NR 12 TC 6 Z9 6 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL, ENGLAND BS1 6BE SN 0022-3727 J9 J PHYS D APPL PHYS JI J. Phys. D-Appl. Phys. PD MAY 21 PY 1997 VL 30 IS 10 BP 1411 EP 1415 DI 10.1088/0022-3727/30/10/003 PG 5 WC Physics, Applied SC Physics GA XA354 UT WOS:A1997XA35400003 ER PT J AU Cheng, LX Leventhal, M Smith, DM Purcell, WR Tueller, J Connors, A Dixon, D Kinzer, RL Skibo, JG AF Cheng, LX Leventhal, M Smith, DM Purcell, WR Tueller, J Connors, A Dixon, D Kinzer, RL Skibo, JG TI A maximum entropy map of the 511 keV positron annihilation line emission distribution near the galactic center SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxy, general; gamma rays, observations ID CENTER REGION; RAY; RADIATION AB We have applied the maximum entropy method to a large data set based on Compton Gamma Ray Observatory (CGRO)/OSSE, Solar Maximum Mission, Transient Gamma-Ray Spectrometer, Gamma-Ray Imaging Spectrometer, HEXAGONE, and FIGARO observational results of the Galactic center 511 keV radiation in order to produce a map of the 511 keV line emission. This map suggests two components: a central bulge with a flux of 5.7 +/- 0.29 x 10(-4) photons cm(-2)s(-1) and a Galactic plane (GP) component with a flux of 2.2 +/- 0.4 x 10(-4) photons cm(-2) s(-1). The central bulge is located at l = -0.degrees 47 +/- 0.degrees 24, b = 0.degrees 1 +/- 0.degrees 18, and FWHM = 5.degrees 28 +/- 0.degrees 48. We note that the position of the GP component coincides with a strong hot spot in the COMPTEL map of 1.8 MeV Al-26 line emission. A comparison between CGRO/OSSE and other instruments with larger field of view suggests an extended diffuse 511 keV emission. An interesting hot spot at l = -4 degrees, b = 7 degrees with a flux of similar to 2 x 10(-4)photons cm(-2)s(-1) is shown on our map. A bootstrap test indicates that the significance level of this feature is 3.5 sigma. C1 NORTHWESTERN UNIV,DEPT PHYS & ASTRON,EVANSTON,IL 60208. NASA,GODDARD SPACE FLIGHT CTR,HIGH ENERGY ASTROPHYS LAB,GREENBELT,MD 20771. UNIV NEW HAMPSHIRE,DURHAM,NH 03824. UNIV CALIF RIVERSIDE,INST GEOPHYS & PLANETARY PHYS,RIVERSIDE,CA 92521. USN,RES LAB,WASHINGTON,DC 20375. RP Cheng, LX (reprint author), UNIV MARYLAND,DEPT ASTRON,COLLEGE PK,MD 20742, USA. RI Tueller, Jack/D-5334-2012 NR 26 TC 27 Z9 27 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 1997 VL 481 IS 1 BP L43 EP L46 DI 10.1086/310638 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA XA546 UT WOS:A1997XA54600011 ER PT J AU Carsey, TP Churchill, DD Farmer, ML Fischer, DJ Pszenny, AA Ross, VB Saltzmann, ES SpringerYoung, M Bonsang, B AF Carsey, TP Churchill, DD Farmer, ML Fischer, DJ Pszenny, AA Ross, VB Saltzmann, ES SpringerYoung, M Bonsang, B TI Nitrogen oxides and ozone production in the North Atlantic marine boundary layer SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID UNPOLLUTED TROPOSPHERE; MIXING RATIOS; SURFACE OZONE; OCEAN; PACIFIC; NOX; DISTRIBUTIONS; TRANSPORT; POLLUTION; EASTERN AB Measurements of reactive nitrogen gases (NO, NO2, NOy), as well as related chemical (O-3, CO, aerosol black carbon, radon, selected nonmethane hydrocarbons) and meteorological parameters were made on board the R/V Malcolm Baldridge prior to and subsequent to the 1992 ASTEX (Atlantic Stratocumulus Transition Experiment) in the North Atlantic Ocean during June and July 1992. Results showed indications of well-defined plumes from North America and Europe from both chemistry and back trajectory data. Elevated ozone concentrations were also observed in airmasses from uninhabited continental regions. Chemical and meteorological data were incorporated into a simple photochemical model in which ozone destruction predominated over generation. The principal reaction leading to ozone destruction was O(D-1) + H2O --> 2OH. C1 CNRS, CTR FAIBLES RADIOACTIV, F-91198 GIF SUR YVETTE, FRANCE. UNIV MIAMI, ROSENSTIEL SCH MARINE & ATMOSPHER SCI, MIAMI, FL 33149 USA. MIT, DEPT CHEM, INT GLOBAL ATMOSPHER CHEM PROGRAM OFF, CAMBRIDGE, MA 02139 USA. USN, OCEANOG OFF, BAY ST LOUIS, MS 39529 USA. RP Carsey, TP (reprint author), NOAA, ATLANTIC OCEANOG & METEOROL LAB, 4301 RICKENBACKER CAUSEWAY, MIAMI, FL 33149 USA. RI Carsey, Thomas/B-7939-2014; Fischer, Charles/A-3843-2017 OI Carsey, Thomas/0000-0001-9964-5092; NR 46 TC 17 Z9 17 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 20 PY 1997 VL 102 IS D9 BP 10653 EP 10665 DI 10.1029/96JD03511 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA XA717 UT WOS:A1997XA71700005 ER PT J AU Taylor, HA AF Taylor, HA TI Induction of labor vs. antenatal monitoring in post-term pregnancy SO AMERICAN FAMILY PHYSICIAN LA English DT Letter RP Taylor, HA (reprint author), USN HOSP,JACKSONVILLE,FL, USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER ACAD FAMILY PHYSICIANS PI KANSAS CITY PA 8880 WARD PARKWAY, KANSAS CITY, MO 64114-2797 SN 0002-838X J9 AM FAM PHYSICIAN JI Am. Fam. Physician PD MAY 15 PY 1997 VL 55 IS 7 BP 2428 EP 2428 PG 1 WC Primary Health Care; Medicine, General & Internal SC General & Internal Medicine GA XA910 UT WOS:A1997XA91000004 PM 9166140 ER PT J AU McElroy, PD Beier, JC Oster, CN Onyango, FK Oloo, AJ Lin, XH Beadle, C Hoffman, SL AF McElroy, PD Beier, JC Oster, CN Onyango, FK Oloo, AJ Lin, XH Beadle, C Hoffman, SL TI Dose- and time-dependent relations between infective Anopheles inoculation and outcomes of Plasmodium falciparum parasitemia among children in western Kenya SO AMERICAN JOURNAL OF EPIDEMIOLOGY LA English DT Article DE Anopheles; Culicidae; malaria; Plasmodium falciparum ID CEREBRAL MALARIA; BED NETS; TRANSMISSION; MORTALITY; SEVERITY; DISEASE; TRIAL; AREA; SEQUESTRATION; MORBIDITY AB Blood-stage level Plasmodium falciparum infection (parasitemia density) is generally elevated prior to, or at the time of, clinical presentation of severe pediatric malaria episodes. Intensity of exposure to infective Anopheles mosquito bites is a suspected determinant of higher density parasitemia. Analyses of entomologic and parasitologic data collected in 1986-1987 were conducted to investigate whether the dose of infective bites predicted the incidence or degree of P. falciparum parasitemia in Kenyan children <6 years old. At 21 consecutive 30-day intervals, a new cohort (n approximate to 50 each) was enrolled, cured of malaria parasites, and monitored over 84 days for recurrent parasitemia. Outcomes included time to parasitemia, time to parasitemia greater than or equal to 5,000/mu l, and parasitemia density. Ecologic and individual-level analyses were conducted. The mean infective bite exposure experienced by each cohort was significantly associated with the incidence of parasitemia (age-adjusted r(2)=0.38, p=0.022) and more strongly associated with the incidence of parasitemia greater than or equal to 5,000/mu l (age-adjusted r(2)=0.72, p <0.001). The infective bite dose, analyzed as a time-dependent covariate, was associated with a 2.8 times higher rate of parasitemia greater than or equal to 5,000/mu l among children exposed to greater than or equal to 1 infective bite per day as compared with the referent (rate ratio (RR)=2.82, 95% confidence interval (CI) 2.24-3.56). Cumulative infective bite exposure, exposure duration, and age were significant predictors of recurrent parasitemia density in multiple linear regression analyses. The results support the contention that reductions in P. falciparum transmission intensity, in the absence of complete elimination, will reduce higher level parasitemia among African children. C1 USN,MED RES INST,MALARIA PROGRAM,ROCKVILLE,MD 20852. UNIV MICHIGAN,SCH PUBL HLTH,DEPT EPIDEMIOL,ANN ARBOR,MI 48109. USA,MED RES UNIT,NAIROBI,KENYA. USA,MED RES UNIT,KISUMU,KENYA. TULANE UNIV,SCH PUBL HLTH,DEPT TROP MED,NEW ORLEANS,LA. WALTER REED ARMY MED CTR,WALTER REED ARMY INST RES,DEPT INFECT DIS,WASHINGTON,DC 20307. KENYA GOVT MED RES CTR,VECTOR BIOL & CONTROL RES CTR,KISUMU,KENYA. UNIV MICHIGAN,SCH PUBL HLTH,DEPT BIOSTAT,ANN ARBOR,MI 48109. FU NIAID NIH HHS [AI-29000] NR 40 TC 29 Z9 29 U1 0 U2 4 PU JOHNS HOPKINS UNIV SCHOOL HYGIENE PUB HEALTH PI BALTIMORE PA 111 MARKET PLACE, STE 840, BALTIMORE, MD 21202-6709 SN 0002-9262 J9 AM J EPIDEMIOL JI Am. J. Epidemiol. PD MAY 15 PY 1997 VL 145 IS 10 BP 945 EP 956 PG 12 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA WY376 UT WOS:A1997WY37600009 PM 9149666 ER PT J AU Shahgholi, M Ohorodnik, S Callahan, JH Fox, A AF Shahgholi, M Ohorodnik, S Callahan, JH Fox, A TI Trace detection of underivatized muramic acid in environmental dust samples by microcolumn liquid chromatography electrospray tandem mass spectrometry SO ANALYTICAL CHEMISTRY LA English DT Article ID ANION-EXCHANGE CHROMATOGRAPHY; CATIONIC SURFACTANTS; INORGANIC ANIONS; CHEMICAL MARKER; ORGANIC DUST; INTERFACE; FRACTION; PEPTIDES; PROTEINS AB Muramic acid (MA) is a universal chemical marker for bacterial cell wall polymers (peptidoglycan) present in complex environmental, industrial, and clinical matrices, Trace analysis of MA has been limited to a handful of laboratories because of the lengthy nature of derivatization procedures necessary for GC/MS and GC/MS/MS. The focus of the current report concerns environmental analysis (organic dust) using LC/MS/MS of native MA. Dust was heated in sulfuric acid to release MA from cell wall polymers. Acid was removed by extraction with an organic base, The samples were passed through a hydrophobic C-18 extraction column to remove nonpolar contaminants, This was followed by binding of MA to a strong cation-exchange extraction column to eliminate neutral and anionic components of the sample, MA was then eluted with hydrochloric acid, which was removed by evaporation, Analysis was done by microscale LC ES/MS/MS using a custom-made Lichrosphere-diol capillary column, C-13-Labeled MA was used as an internal standard. Total sample preparation takes approximately 12 h, The simplicity of the sample preparation may eventually allow RIA analysis to be used in a host of applications, including air monitoring for biocontamination, This is the first report, to our knowledge, of microscale LC ES/MS/MS analysis for MA (or, indeed, any other sugar monomer) in a complex matrix. C1 UNIV S CAROLINA,SCH MED,DEPT MICROBIOL & IMMUNOL,COLUMBIA,SC 29208. RP Shahgholi, M (reprint author), USN,RES LAB,DIV CHEM,CODE 6113,WASHINGTON,DC 20375, USA. NR 28 TC 18 Z9 18 U1 1 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAY 15 PY 1997 VL 69 IS 10 BP 1956 EP 1960 DI 10.1021/ac960914x PG 5 WC Chemistry, Analytical SC Chemistry GA WX861 UT WOS:A1997WX86100024 ER PT J AU Narang, U Gauger, PR Ligler, FS AF Narang, U Gauger, PR Ligler, FS TI Capillary-based displacement flow immunosensor SO ANALYTICAL CHEMISTRY LA English DT Article ID ENZYME-IMMUNOASSAY; 2,4,6-TRINITROTOLUENE; WATER; TNT; EXPLOSIVES; TRINITROTOLUENE; ANTIBODIES; BIOSENSOR; ATRAZINE; ELISA AB We report on the preparation of a novel capillary flow immunosensor for 2,4,6-trinitrotoluene (TNT). Anti-TNT antibody is immobilized onto the silanized inner walls of an 800-mu m-i.d. glass capillary using a heterobifunctional crosslinker, followed by saturating the capillary with fluorophore-labeled antigen. To perform the assay, an aliquot of TNT solution is injected into the capillary. TNT competes for the binding pocket of the fluorophore-labeled antigen, which is detected downstream, We have demonstrated that the sensitivity of the capillary immunosensor is improved by at least 2 orders of magnitude compared to that of conventional packed-column;or membrane-based displacement flow immunosensors. The limit of detection (S/N > 3) for TNT using the capillary immunosensor is 15 pg/mL (7 fmol), and the linear dynamic range is 1-250 ng/mL. The entire assay can be performed in less than 3 min. During 15 injections of 100 ng/mL TNT solution, the signal reproducibility (RSD) was maintained to within 4%. C1 USN,RES LAB,CTR BIOMOL SCI & ENGN,WASHINGTON,DC 20375. NR 47 TC 47 Z9 47 U1 1 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAY 15 PY 1997 VL 69 IS 10 BP 1961 EP 1964 DI 10.1021/ac961037y PG 4 WC Chemistry, Analytical SC Chemistry GA WX861 UT WOS:A1997WX86100025 ER PT J AU Walker, DN Amatucci, WE Ganguli, G Antoniades, JA Bowles, JH Duncan, D Gavrishchaka, V Koepke, ME AF Walker, DN Amatucci, WE Ganguli, G Antoniades, JA Bowles, JH Duncan, D Gavrishchaka, V Koepke, ME TI Perpendicular ion heating by velocity-shear-driven waves SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID ELECTRIC-FIELD; CYCLOTRON TURBULENCE; ELECTROSTATIC-WAVES; MAGNETIC-FIELD; INSTABILITY; IONOSPHERE; SIMULATION; ALTITUDE; FOUNTAIN; DENSITY AB Perpendicular ion heating resulting from velocity-shear-driven ion-cyclotron waves has been measured for the first time. The experiment was performed in the Naval Research Laboratory's Space Physics Simulation Chamber (SPSC) under plasma conditions approaching those in the natural space environment. Sheared cross-field flow is induced by a controllable, inhomogeneous, transverse, DC electric field (L-E similar to (1 - 2)rho(i)) created without drawing significant levels of magnetic-field aligned current. Mode frequency data suggest that the most efficient heating occurs when the Doppler shifted frequency in the ion frame is located near a harmonic of the ion-cyclotron frequency. C1 W VIRGINIA UNIV,DEPT PHYS,MORGANTOWN,WV 26506. RP Walker, DN (reprint author), USN,RES LAB,DIV PLASMA PHYS,CODE 6700,4555 OVERLOOK AVE SW,WASHINGTON,DC 20375, USA. NR 33 TC 25 Z9 25 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 15 PY 1997 VL 24 IS 10 BP 1187 EP 1190 DI 10.1029/97GL01102 PG 4 WC Geosciences, Multidisciplinary SC Geology GA WZ425 UT WOS:A1997WZ42500008 ER PT J AU Gruber, JB Wright, AO Seltzer, MD Zandi, B Merkle, LD Hutchinson, JA Morrison, CA Allik, TH Chai, BHT AF Gruber, JB Wright, AO Seltzer, MD Zandi, B Merkle, LD Hutchinson, JA Morrison, CA Allik, TH Chai, BHT TI Site-selective excitation and polarized absorption and emission spectra of trivalent thulium and erbium in strontium fluorapatite SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ENERGY-LEVELS; LASER; FLUOROPHOSPHATE; CRYSTALS AB Polarized fluorescence spectra produced by site-selective excitation, and conventional polarized absorption spectra were obtained for Tm3+ and Er3+ ions individually incorporated into single crystals of strontium fluorapatite, Sr-5(PO4)(3)F, also known as SFAP. Substitution of the trivalent rare earth ion for divalent strontium was achieved by passive charge compensation during Czochralski growth of the fluorapatite crystals. Spectra were obtained between 1780 and 345 nm at temperatures from 4 K to room temperature on crystals having the hexagonal structure [P6(3)/m(C-6h(2))]. The polarized fluorescence spectra due to transitions from multiplet manifolds of Tm3+(4f(12)), including D-1(2), (1)G(4), and H-3(4) to manifolds H-3(6) (the ground-state manifold), F-3(4), H-3(5), H-3(4), and F-3(3) were analyzed for the details of the crystal-field splitting of the manifolds. Fluorescence Lifetimes were measured for Tm3+ transitions from D-1(2), (1)G(4), and H-3(4) at room temperature and from (1)G(4) at 16 K. Results of the analysis indicate that the majority of Tm3+ ions occupy sites having C-s symmetry. A point-charge lattice-sum calculation was made in which the crystal-field components, A(nm), were determined assuming that trivalent thulium replaces divalent strontium in the metal site having C-s symmetry. Results support the conclusion that the nearest-neighbor fluoride (F-) is replaced by divalent oxygen (O2-), thus preserving overall charge neutrality and local symmetry. Crystal-field splitting calculations predict energy levels in agreement with results obtained from an analysis of the experimental data. By varying the crystal-field parameters, B-nm, we obtained a rms difference of 7 cm(-1) between 43 calculated and experimental Stark levels for Tm3+(4f(12)) in Tm:SFAP. Absorption and fluorescence spectra are also reported for Er3+ ions in Er:SFAP. Measurement of the temporal decay of the room temperature fluorescence from the I-4(11/2) and I-4(13/2) manifolds yielded fluorescence lifetimes of 230+/-20 mu s and 8.9+/-0.1 ms, respectively. The experimental Stark levels obtained from an analysis of the spectroscopic data were compared with a crystal-field splitting calculation. The initial set of B-nm parameters for Er3+(4f(11)) was established from the three-parameter theory and the final set of B-nm parameters obtained for Tm3+(4f(12)) in Tm:SFAP. The best overall agreement between calculated and experimental Stark levels is 8 cm(-1) for 48 Stark levels, representing 12 observed multiplet manifolds of Er3+(4f(11)) in Er:SFAP. (C) 1997 American Institute of Physics. C1 USN,AIR WARFARE CTR,RES & TECHNOL DIV,CHINA LAKE,CA 93555. USA,RES LAB,IR OPT TECHNOL OFC,FT BELVOIR,VA 22060. USA,NIGHT VIS & ELECT SENSORS DIRECTORATE,FT BELVOIR,VA 22060. USA,RES LAB,ADELPHI,MD 20783. SCI APPLICAT INT CORP,MCLEAN,VA 22102. UNIV CENT FLORIDA,CTR RES ELECTROOPT & LASERS,ORLANDO,FL 32836. RP Gruber, JB (reprint author), SAN JOSE STATE UNIV,DEPT PHYS,SAN JOSE,CA 95192, USA. NR 38 TC 11 Z9 11 U1 1 U2 10 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1997 VL 81 IS 10 BP 6585 EP 6598 DI 10.1063/1.365197 PG 14 WC Physics, Applied SC Physics GA WZ575 UT WOS:A1997WZ57500005 ER PT J AU Rao, MV Gardner, JA Chi, PH Holland, OW Kelner, G Kretchmer, J Ghezzo, M AF Rao, MV Gardner, JA Chi, PH Holland, OW Kelner, G Kretchmer, J Ghezzo, M TI Phosphorus and boron implantation in 6H-SiC SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID STOICHIOMETRIC DISTURBANCES; COMPOUND SEMICONDUCTORS; ION-IMPLANTATION; SILICON-CARBIDE; DIFFUSION; PROFILES; DISTRIBUTIONS AB Phosphorus and boron ion implantations were performed at various energies in the 50 keV-4 MeV range. Range statistics of P+ and B+ were established by analyzing the as-implanted secondary ion mass spectrometry depth profiles. Anneals were conducted in the temperature range of 1400-1700 degrees C using either a conventional resistive heating ceramic processing furnace or a microwave annealing station. The P implant was found to be stable at any annealing temperature investigated, but the B redistributed during the annealing process. The implant damage is effectively annealed as indicated by Rutherford backscattering measurements. For the 250 keV/1.2x10(15) cm(-2) P implant, annealed at 1600 degrees C for 15 min, the measured donor activation at room temperature is 34% with a sheet resistance of 4.8x10(2) Omega/square. The p-type conduction could not be measured for the B implants. (C) 1997 American Institute of Physics. C1 NIST,GAITHERSBURG,MD 20899. OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. USN,RES LAB,WASHINGTON,DC 20375. GE CO,CORP RES & DEV,SCHENECTADY,NY 12301. RP Rao, MV (reprint author), GEORGE MASON UNIV,DEPT ELECT & COMP ENGN,FAIRFAX,VA 22030, USA. NR 38 TC 46 Z9 46 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1997 VL 81 IS 10 BP 6635 EP 6641 DI 10.1063/1.365236 PG 7 WC Physics, Applied SC Physics GA WZ575 UT WOS:A1997WZ57500011 ER PT J AU Dorsey, PC Rappoli, BJ Grabowski, KS Lubitz, P Chrisey, DB Horwitz, JS AF Dorsey, PC Rappoli, BJ Grabowski, KS Lubitz, P Chrisey, DB Horwitz, JS TI Stress-induced magnetic anisotropy in thick oriented NiZn-ferrite films on (100) MgO substrates SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID PULSED-LASER DEPOSITION AB Thick films (10-12 mu m) of NiZn-ferrite (Ni0.6Zn0.4Fe2O4) were grown on single-crystal (100) magnesium oxide substrates using pulsed laser deposition (PLD). The morphology, phase, orientation, strain, and magnetic properties of the as-deposited films were investigated as a function of substrate temperature (400-700 degrees C) and O-2 background pressure (50-200 mTorr). Compositional analysis shows that the PLD NiZn-ferrite films are about 45% Zn deficient when grown using a standard polycrystalline single phase Ni0.4Zn0.6Fe2O4 target regardless of substrate temperature or O-2 pressure. However, Zn-rich targets were successfully used to compensate for the Zn deficiency in the NiZn-ferrite films. PLD NiZn-ferrite films grown at 700 degrees C exhibit the highest degree of crystalline quality and nearly bulk saturation magnetization values (i.e., 5000 G). At low O-2 pressures (<75 mTorr) the films, which were grown at 700 degrees C, are under a significant compressive stress. The stress decreases when the PLD NiZn-ferrite films are grown in higher O-2 pressures but the crystalline quality and surface morphology deteriorate. The compressive stress produces a planar anisotropy field of about 1000-3500 Oe depending on the O-2 pressure, which is consistent with the stress results from x-ray diffraction measurements on the NiZn-ferrite films. It is hypothesized that the film stress is largely the result of oxygen loss from the films during deposition. (C) 1997 American Institute of Physics. C1 USN,RES LAB,WASHINGTON,DC 20375. OI Grabowski, Kenneth/0000-0003-0816-001X NR 17 TC 23 Z9 25 U1 0 U2 12 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 15 PY 1997 VL 81 IS 10 BP 6884 EP 6891 DI 10.1063/1.365249 PG 8 WC Physics, Applied SC Physics GA WZ575 UT WOS:A1997WZ57500049 ER PT J AU Chu, PC Fralick, CR Haeger, SD Carron, MJ AF Chu, PC Fralick, CR Haeger, SD Carron, MJ TI A parametric model for the Yellow Sea thermal variability SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID CHINA AB A thermal parametric model has been developed for analyzing observed regional sea temperature profiles based on a layered structure of temperature fields (mixed layer, thermocline, and deep layers). It contains three major components: (1) a first-guess parametric model, (2) high-resolution profiles interpolated from observed profiles, and (3) fitting of high-resolution profiles to the parametric model. The output of this parametric model is a set of major characteristics of each profile: sea surface temperature, mixed-layer depth, thermocline depth, thermocline temperature gradient, and deep layer stratification. Analyzing nearly 15,000 Yellow Sea historical (1950-1988) temperature profiles (conductivity-temperature-depth station, 4825; expendable bathythermograph, 3213; bathythermograph, 6965) from the Naval Oceanographic Office's Master Oceanographic Observation Data Set by this parametric model, the Yellow Sea thermal field reveals dual structure: one layer (vertically uniform) during winter and multilayer (mixed layer, thermocline, sublayer) during summer. Strong seasonal variations were also found in mixed-layer depth, thermocline depth, and thermocline strength. C1 USN,OCEANOG OFF,BAY ST LOUIS,MS 39529. RP Chu, PC (reprint author), USN,POSTGRAD SCH,CODE OC CU,MONTEREY,CA 93943, USA. NR 12 TC 29 Z9 37 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD MAY 15 PY 1997 VL 102 IS C5 BP 10499 EP 10507 DI 10.1029/97JC00444 PG 9 WC Oceanography SC Oceanography GA XA569 UT WOS:A1997XA56900010 ER PT J AU Pechhold, K Patterson, NB Craighead, N Lee, KP June, CH Harlan, DM AF Pechhold, K Patterson, NB Craighead, N Lee, KP June, CH Harlan, DM TI Inflammatory cytokines IFN-gamma plus TNF-alpha induce regulated expression of CD80 (B7-1) but not CD86 (B7-2) on murine fibroblasts SO JOURNAL OF IMMUNOLOGY LA English DT Article ID T-CELL ACTIVATION; PANCREATIC BETA-CELLS; TUMOR-NECROSIS-FACTOR; COSTIMULATORY MOLECULES; TRANSGENIC MICE; CD28 RECEPTOR; LYMPHOCYTES-T; ANTIGEN; CTLA-4; TOLERANCE AB Optimal T cell activation requires signals delivered via both the TCR and the costimulatory receptors. Considerable experimental data now suggest that this costimulatory signal is generated predominantly by CD28 when engaged by its ligands CD80 (B7-1) and/or CD86 (B7-2). Whether T cell activation is controlled in part by regulated CD80 and/or CD86 expression has been incompletely explored. Here, we report that CD80 can be expressed constitutively by murine fibroblasts and up-regulated after treatment with IFN-gamma plus TNF-alpha. CD80 expression and function was confirmed by 1) Northern analysis, 2) specific immunoprecipitation of a similar to 69-kDa surface protein that comigrated with CD80 precipitated from CD80-transfected CHO cells, and 3) two independent assays for costimulation of Ag-specific T cell activation. Taken together, these observations suggest that CD28/CTLA-4 ligands are expressed on a wider variety of tissues than previously suspected and that their expression is dynamically regulated. Consequently, these results might explain previous observations that inflammatory cytokines can result in autoimmune responses. RP Pechhold, K (reprint author), USN,MED RES INST,IMMUNE CELL BIOL PROGRAM,8901 WISCONSIN AVE,BETHESDA,MD 20889, USA. NR 53 TC 51 Z9 54 U1 0 U2 1 PU AMER ASSOC IMMUNOLOGISTS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 SN 0022-1767 J9 J IMMUNOL JI J. Immunol. PD MAY 15 PY 1997 VL 158 IS 10 BP 4921 EP 4929 PG 9 WC Immunology SC Immunology GA WX987 UT WOS:A1997WX98700050 PM 9144510 ER PT J AU Carter, AC Bouldin, CE Kemner, KM Bell, MI Woicik, JC Majetich, SA AF Carter, AC Bouldin, CE Kemner, KM Bell, MI Woicik, JC Majetich, SA TI Surface structure of cadmium selenide nanocrystallites SO PHYSICAL REVIEW B LA English DT Article ID ABSORPTION FINE-STRUCTURE; SEMICONDUCTOR CLUSTERS; AQUEOUS-SOLUTIONS; TRANSITION; COMPLEXES; SULFIDE; FIELD AB Extended x-ray-absorption fine structure (EXAFS), Fourier-transform infrared absorption (FTIR), and elemental analysis were used on a variety of CdSe nanocrystallites (NC's) to study surface structure. All CdSe NC's were grown by standard inverse micelle techniques. Two sets of NC's samples were made. One set was made so that only the size of the NC's was varied, while the surface treatment was kept the same. The other set was made so that only the surface treatment was varied, while the size distribution was kept the same. For the EXAFS experiments, reference compounds similar in structure were measured. FTIR found surface Cd atoms to be passivated by pyridines and water groups. Fourier-filtered first-shell Cd EXAFS also supports the existence of water groups attached to the surface Cd atoms. The lack of any SeO and Si(CH3)(3) in the FTIR signal indicates that most surface Se atoms have unterminated bonds. Fourier-filtered first-shell Se EXAFS spectra indicate that Se has only Cd as its first-nearest neighbor, and that the coordination number is reduced from the bulk value, suggesting surface Se atoms are unpassivated. Our data support the existence of surface Se lone-pair orbitals that can trap an optically excited hole. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20818. CARNEGIE MELLON UNIV,PITTSBURGH,PA 15213. RP Carter, AC (reprint author), USN,RES LAB,WASHINGTON,DC 20357, USA. RI Majetich, Sara/B-1022-2015 OI Majetich, Sara/0000-0003-0848-9317 NR 31 TC 56 Z9 56 U1 1 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 15 PY 1997 VL 55 IS 20 BP 13822 EP 13828 DI 10.1103/PhysRevB.55.13822 PG 7 WC Physics, Condensed Matter SC Physics GA XD170 UT WOS:A1997XD17000073 ER PT J AU Jernigan, GG Thompson, PE Silvestre, CL AF Jernigan, GG Thompson, PE Silvestre, CL TI Quantitative measurements of Ge surface segregation during SiGe alloy growth SO SURFACE SCIENCE LA English DT Article DE molecular beam epitaxy; silicon-germanium; surface segregation; X-ray photoelectron spectroscopy ID MOLECULAR-BEAM EPITAXY; ENERGY ION-SCATTERING; TEMPERATURE-DEPENDENCE; SI/GE SUPERLATTICES; BURIED LAYER; SI(100); SPECTROSCOPY; KINETICS AB Ge segregation during the growth of Si1-xGex alloys (x=5, 10, 20, and 40%) was studied using X-ray photoelectron spectroscopy. The alloys were grown in thicknesses up to 20.0 nm at 500 degrees C to measure quantitatively the amount of segregated surface Ge. The length of alloy needed to reach steady-state growth edge was found to decrease with increasing alloy concentration (4.8, 2.8, 2.4, and 2.0 nm, respectively). It was found that each alloy had a complete monolayer of Ge on the surface and an increasing amount of segregated Ge in the second layer (20, 55, 80, and 95%, respectively) during steady-state growth. An increase in the temperature of alloy growth (400-750 degrees C) resulted in an increase in the leading edge of alloy growth but did not change the amount of segregated Ge during steady-state growth. We propose that film stress is responsible for the amount of Ge segregation. (C) 1997 Elsevier Science B.V. RP Jernigan, GG (reprint author), USN,RES LAB,CODE 6812,4555 OVERLOOK AVE SW,WASHINGTON,DC 20375, USA. NR 26 TC 36 Z9 36 U1 0 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD MAY 15 PY 1997 VL 380 IS 2-3 BP 417 EP 426 DI 10.1016/S0039-6028(97)00036-8 PG 10 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA XF843 UT WOS:A1997XF84300031 ER PT J AU Henderson, DR AF Henderson, DR TI Best practices - What are price wars good For? Absolutely nothing. SO FORTUNE LA English DT Editorial Material RP Henderson, DR (reprint author), USN,POSTGRAD SCH,MONTEREY,CA 93940, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU TIME INC PI NEW YORK PA TIME & LIFE BUILDING ROCKEFELLER CENTER, NEW YORK, NY 10020-1393 SN 0015-8259 J9 FORTUNE JI Fortune PD MAY 12 PY 1997 VL 135 IS 9 BP 156 EP 156 PG 1 WC Business SC Business & Economics GA WV179 UT WOS:A1997WV17900026 ER PT J AU Flatte, ME Byers, JM AF Flatte, ME Byers, JM TI Local electronic structure of a single magnetic impurity in a superconductor SO PHYSICAL REVIEW LETTERS LA English DT Article AB We present the first three-dimensional, self-consistent calculation of the electronic structure near a strong classical magnetic impurity in a superconductor. Localized excited states are found within the energy gap which are half electron and half hole. The spatial structure of the positive-frequency (electronlike) spectral weight (or local density of states) can differ strongly from that of the negative frequency (holelike) spectral weight. The effect of the impurity on the continuum states above the energy gap is calculated with good spectral resolution for the first time. For sufficiently strong Impurity potentials, the order parameter may change sign at the impurity site. C1 USN,RES LAB,WASHINGTON,DC 20375. RP Flatte, ME (reprint author), UNIV IOWA,DEPT PHYS & ASTRON,IOWA CITY,IA 52242, USA. NR 31 TC 54 Z9 54 U1 1 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAY 12 PY 1997 VL 78 IS 19 BP 3761 EP 3764 DI 10.1103/PhysRevLett.78.3761 PG 4 WC Physics, Multidisciplinary SC Physics GA WY166 UT WOS:A1997WY16600043 ER PT J AU Luhman, ML Luhman, KL Benedict, T Jaffe, DT Fischer, J AF Luhman, ML Luhman, KL Benedict, T Jaffe, DT Fischer, J TI Near-infrared spectra of IC 59/63 and NGC 1535: Comparing infrared and ultraviolet observations of H-2 SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared, ISM, lines and bands; ISM, individual (IC 59, IC 63); ISM, molecules; molecular processes; planetary nebulae, individual (NGC 1535); reflection nebulae ID MOLECULAR-HYDROGEN EMISSION; PLANETARY-NEBULAE; LINE EMISSION; PHOTODISSOCIATION REGIONS; GAMMA-CASSIOPEIAE; INTERSTELLAR H2; EXCITATION; RADIATION; ORION; IC-63 AB We present observations of near-infrared H-2 line emission toward the reflection/emission nebulae, IC 59 and IC 63, and the planetary nebula, NGC 1535. Each source has been observed previously in the ultraviolet, where H-2 was detected in emission toward IC 63 and in absorption toward NGC 1535. In IC 63, we have detected the 1.601 mu m upsilon = 6-4 Q(1), 2.121 mu m upsilon = 1-0 S(1), and 2.247 mu m upsilon = 2-1 S(1) lines of H-2 arising from a near-infrared fluorescent cascade following ultraviolet continuum pumping. The detection marks the first time that both infrared and ultraviolet portions of the H-2 fluorescent cascade have been measured in a region exposed to far-ultraviolet continuum photons. Furthermore, we also report 1-0 S(1) and 2-1 S(1) fluorescent emission toward IC 59, a source previously thought to display no H-2 fluorescence and considered devoid of molecules based on ultraviolet and CO observations. Toward NGC 1535, we find no H-2 emission in the near-infrared, in spite of the reported ultraviolet H-2 absorption. C1 UNIV ARIZONA,STEWARD OBSERV,TUCSON,AZ 85721. UNIV TEXAS,DEPT ASTRON,AUSTIN,TX 78712. RP Luhman, ML (reprint author), USN,RES LAB,DIV REMOTE SENSING,CODE 7217,WASHINGTON,DC 20375, USA. NR 40 TC 15 Z9 15 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 1997 VL 480 IS 2 BP L133 EP L136 DI 10.1086/310627 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA WW856 UT WOS:A1997WW85600013 ER PT J AU Resmini, RG Kappus, ME Aldrich, WS Harsanyi, JC Anderson, M AF Resmini, RG Kappus, ME Aldrich, WS Harsanyi, JC Anderson, M TI Mineral mapping with HYperspectral Digital Imagery Collection Experiment (HYDICE) sensor-data at Cuprite, Nevada, USA SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID IMAGING SPECTROMETER DATA; MU-M; INFORMATION; SCANNER; SPECTRA AB The areal distributions of the minerals alunite, kaolinite, and calcite in an approximately 1.8 km(2) area of the Cuprite mining district, Nevada, have been mapped by applying constrained energy minimization (CEM) to remotely sensed data from the HYperspectral Digital Imagery Collection Experiment (HYDICE) sensor, a 210 channel, 0.4 mu m to 2.5 mu m airborne hyperspectral imaging spectrometer. The image data analysed here have ground sample distances of approximately 3 m. CEM is a powerful and rapid technique for mineral mapping which requires only the spectrum of the mineral to be mapped and no prior knowledge of background constituents. Other spectral image processing techniques applied to the data produce results essentially identical to those of CEM and which agree with the mapping of Ashley and Abrams (1980). C1 APPL SIGNAL & IMAGE TECHNOL CO,PASADENA,MD 21122. USN,RES LAB,SPAWAR 43,WASHINGTON,DC 20375. RP Resmini, RG (reprint author), SCI APPLICAT INT CORP,4501 DALY DR,SUITE 400,CHANTILLY,VA 20151, USA. NR 37 TC 51 Z9 71 U1 2 U2 5 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD MAY 10 PY 1997 VL 18 IS 7 BP 1553 EP 1570 DI 10.1080/014311697218278 PG 18 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA WV632 UT WOS:A1997WV63200009 ER PT J AU Froimowitz, M Deutsch, HM Shi, Q Wu, KM Glaser, R Adin, I George, C Schweri, MM AF Froimowitz, M Deutsch, HM Shi, Q Wu, KM Glaser, R Adin, I George, C Schweri, MM TI Further evidence for a dopamine reuptake pharmacophore. The effect of N-methylation on threo-methylphenidate and its analogs SO BIOORGANIC & MEDICINAL CHEMISTRY LETTERS LA English DT Article ID CONFORMATIONAL-ANALYSIS; SEROTONIN UPTAKE; COCAINE; NOREPINEPHRINE; AFFINITY; BLOCKERS; BINDING; CFT AB N-methyl derivatives of methylphenidate and four analogs were synthesized and assayed for affinity at the dopamine transporter. The binding affinities of the N-methyl compounds were consistently lower by a factor ranging from 4 to 30 as compared with the corresponding secondary amine. This is consistent with the predictions of a pharmacophore model of compounds that bind to the dopamine transporter. (C) 1997 Elsevier Science Ltd. C1 GEORGIA INST TECHNOL,SCH CHEM & BIOCHEM,ATLANTA,GA 30332. BEN GURION UNIV NEGEV,DEPT CHEM,IL-84105 BEER SHEVA,ISRAEL. USN,RES LAB,STRUCT MATTER LAB,WASHINGTON,DC 20375. MERCER UNIV,SCH MED,DIV BASIC MED SCI,MACON,GA 31207. RP Froimowitz, M (reprint author), PHARM ECO LABS,128 SPRING ST,LEXINGTON,MA 02173, USA. NR 17 TC 23 Z9 23 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0960-894X J9 BIOORG MED CHEM LETT JI Bioorg. Med. Chem. Lett. PD MAY 6 PY 1997 VL 7 IS 9 BP 1213 EP 1218 DI 10.1016/S0960-894X(97)00193-5 PG 6 WC Chemistry, Medicinal; Chemistry, Organic SC Pharmacology & Pharmacy; Chemistry GA XA648 UT WOS:A1997XA64800025 ER PT J AU Engel, GE AF Engel, GE TI Linear response and the exchange-correlation hole within a screened-exchange density functional theory SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTRON-GAS; BAND-GAPS; APPROXIMATION; ENERGIES; LIQUIDS AB Justification is provided for a hybrid density functional for electronic systems [Seidl ct al., Phys. Rev. B 53, 3764 (1996)] combining a screened-exchange term with a local approximation to the remaining exchange-correlation energy. It is argued that this functional correctly models an important part of the exchange-correlation hole. With an appropriate and explicitly specified choice of interaction, it accurately reproduces the exact linear density response function of the homogeneous electron gas. These results imply significant improvements over the usual local density approximation (LDA). C1 USN,RES LAB,WASHINGTON,DC 20375. RP Engel, GE (reprint author), GEORGE MASON UNIV,COMPUTAT SCI INST,FAIRFAX,VA 22030, USA. NR 21 TC 21 Z9 21 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAY 5 PY 1997 VL 78 IS 18 BP 3515 EP 3518 DI 10.1103/PhysRevLett.78.3515 PG 4 WC Physics, Multidisciplinary SC Physics GA WX518 UT WOS:A1997WX51800024 ER PT J AU Kroes, GJ Baerends, EJ Mowrey, RC AF Kroes, GJ Baerends, EJ Mowrey, RC TI Six-dimensional quantum dynamics of dissociative chemisorption of (v=0, j=0) H-2 on Cu(100) SO PHYSICAL REVIEW LETTERS LA English DT Article ID POTENTIAL-ENERGY SURFACE; ASSOCIATIVE DESORPTION; NI-SURFACES; ADSORPTION; CU(111); APPROXIMATION; SCATTERING; MOLECULES; HYDROGEN; EXCHANGE AB Six-dimensional quantum dynamics calculations are now possible for fully activated dissociative chemisorption of Ha We present results for the reaction of (v = 0, j = 0) H-2 on Cu(100); The potential energy surface was taken from density functional theory (DFT), using the generalized gradient approximation. Comparison to experiment suggests that, on average, the DFT method overestimates the barriers to dissociation by 0.18 eV for H-2 + Cu(100). C1 FREE UNIV AMSTERDAM, NL-1081 HV AMSTERDAM, NETHERLANDS. USN, RES LAB, THEORET CHEM SECT, WASHINGTON, DC 20375 USA. RP LEIDEN UNIV, LEIDEN INST CHEM, GORLAEUS LABS, POB 9502, NL-2300 RA LEIDEN, NETHERLANDS. RI Baerends, Evert Jan/F-7206-2011 OI Baerends, Evert Jan/0000-0002-3045-4906 NR 33 TC 117 Z9 118 U1 0 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAY 5 PY 1997 VL 78 IS 18 BP 3583 EP 3586 DI 10.1103/PhysRevLett.78.3583 PG 4 WC Physics, Multidisciplinary SC Physics GA WX518 UT WOS:A1997WX51800041 ER PT J AU Zacovic, JW McGuirk, TD Knoop, KJ AF Zacovic, JW McGuirk, TD Knoop, KJ TI Bilateral hyphemas as a result of air bag deployment SO AMERICAN JOURNAL OF EMERGENCY MEDICINE LA English DT Letter ID INJURY; KERATITIS RP Zacovic, JW (reprint author), USN,MED CTR,DEPT EMERGENCY MED,PORTSMOUTH,VA 23708, USA. NR 10 TC 7 Z9 7 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 SN 0735-6757 J9 AM J EMERG MED JI Am. J. Emerg. Med. PD MAY PY 1997 VL 15 IS 3 BP 323 EP 324 DI 10.1016/S0735-6757(97)90029-2 PG 2 WC Emergency Medicine SC Emergency Medicine GA WY253 UT WOS:A1997WY25300030 PM 9149001 ER PT J AU Phillips, WT Lemen, L Goins, B Rudolph, AS Klipper, R Fresne, D Jerabek, PA Emch, ME Martin, C Fox, PT McMahan, CA AF Phillips, WT Lemen, L Goins, B Rudolph, AS Klipper, R Fresne, D Jerabek, PA Emch, ME Martin, C Fox, PT McMahan, CA TI Use of oxygen-15 to measure oxygen-carrying capacity of blood substitutes in vivo SO AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY LA English DT Article DE liposome-encapsulated hemoglobin; hemoglobin ID LIPOSOME-ENCAPSULATED HEMOGLOBIN; POSITRON EMISSION TOMOGRAPHY; SYSTEM; RABBIT; LUNGS; FLOW; O-15 AB A method for determining oxygen-carrying capacity of blood substitutes has been developed using the short-lived cyclotron-produced positron-emitting isotope O-15. This method measures the oxygen-carrying capacity of the blood substitutes in vivo in the presence of red blood cells and allows determination of changes in the oxygen-carrying capacity over time after exchange transfusion. This method is applied to the blood substitutes of liposome-encapsulated hemoglobin (LEH) and cell-free hemoglobin (Hb). We have used O-15 (half-life of 2 min) to quantitate the lung uptake and tissue delivery of [O-15(2)]LEH. Lung uptake studies were performed in intu bated, catheterized rats after a 40% exchange transfusion of bovine LEH (LEBH; 0.68 g Hb/kg body wt), human hemolysate LEH (LEHH; 1.0 g Hb/kg body wt), or free bovine hemoglobin (SFHS; 0.56 g Hb/kg body wt). A bolus inhalation of O-15(2) (3-5 mCi) was given at 15 min, 3 h, and 24 h posttransfusion. Arterial blood samples were collected, spun, and separated into LEH, red blood cell, and plasma fractions. O-15 activity and hemoglobin content were determined for each fraction. Oxygen-carrying capacity was calculated as a percentage of the original red blood cell fraction removed. For LEBH, the carrying capacity was 15% at 15 min, 13% at 3 h, and 1% at 24 h. For LEHH, the carrying capacity was 30% at 15 min, 26% at 3 h, and 19% at 24 h. The marked decrease in carrying capacity at 24 h for LEBH compared with LEHH was attributable to the increased formation of methemoglobin in the circulating LEBH rather than increased removal from circulation, because total hemoglobin concentrations measured for both LEH samples decreased at a similar rate during the 24 h. The presence of methemoglobin reductase and other naturally occurring antioxidants in the LEHH may be responsible for maintaining the higher levels of oxyhemoglobin. Oxygen-carrying capacity for SFHS also decreased over time but at a much sharper rate compared with both LEH formulations. The carrying capacity for SFHS of 8% measured at 15 min decreased to 0.3% at 3 h and undetectable levels at 24 h. This sharper decrease in carrying capacity for SFHS is attributable to the rapid removal of the hemoglobin from circulation. C1 Univ Texas, Hlth Sci Ctr, Dept Radiol, San Antonio, TX 78284 USA. Univ Texas, Hlth Sci Ctr, Dept Pathol, San Antonio, TX 78284 USA. Univ Texas, Hlth Sci Ctr, Res Imaging Ctr, San Antonio, TX 78284 USA. USN, Res Lab, Washington, DC 20375 USA. RP Phillips, WT (reprint author), Univ Texas, Hlth Sci Ctr, Dept Radiol, 7703 Floyd Curl Dr, San Antonio, TX 78284 USA. RI Goins, Beth/F-1311-2010; Phillips, William/E-8427-2010; Fox, Peter/B-4725-2010 OI Phillips, William/0000-0001-8248-7817; Fox, Peter/0000-0002-0465-2028 NR 33 TC 17 Z9 17 U1 0 U2 3 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 SN 0363-6135 J9 AM J PHYSIOL-HEART C JI Am. J. Physiol.-Heart Circul. Physiol. PD MAY PY 1997 VL 272 IS 5 BP H2492 EP H2499 PG 8 WC Cardiac & Cardiovascular Systems; Physiology; Peripheral Vascular Disease SC Cardiovascular System & Cardiology; Physiology GA WY638 UT WOS:A1997WY63800052 ER PT J AU Slocum, KA Gorman, JD Puckett, ML Jones, SB AF Slocum, KA Gorman, JD Puckett, ML Jones, SB TI Resolution of abnormal MR signal intensity in patients with stress fractures of the femoral neck SO AMERICAN JOURNAL OF ROENTGENOLOGY LA English DT Article; Proceedings Paper CT 96th Annual Meeting of the American-Roentgen-Ray-Society CY MAY 05-10, 1996 CL SAN DIEGO, CA SP Amer Roentgen Ray Soc AB OBJECTIVE. The purpose of this study was to describe the natural evolution of abnormal MR signal intensity after the diagnosis of a stress fracture of the femoral neck and to ascertain the time to resolution of that abnormal signal intensity. SUBJECTS AND METHODS. Ten patients who had been previously diagnosed with stress fractures of the femoral neck after positive MR scans of the hip were examined with MR imaging at regular intervals. In each patient T1-weighted and short inversion time inversion recovery (STIR) sequences were obtained until the abnormally bright, diffuse MR signal intensity (representing edema) disappeared from the STIR images. Time to resolution was correlated with each patient's age and presence or absence of a fatigue line on MR imaging. Statistical analysis was done using Fisher's exact test. RESULTS. Edema resolved in seven patients within 3 months of initial diagnosis, in two patients within 6 months, and in the remaining patient within 12 months. We found no statistically significant correlation between time to resolution and patient age or the presence of a fatigue line an MR imaging, Residual sclerosis occurred in five patients, all of whom had a fatigue line. Two of these patients developed bright T1 signal (fatty marrow conversion) around the area of sclerosis. In the remaining three patients, STIR images revealed a brightened fatigue line, which we presumed was caused by granulation tissue. CONCLUSION. In this study, 90% of patients showed resolution of abnormal MR signal intensity on STIR imaging within 6 months of the initial diagnosis of stress fracture of the femoral neck, Such data may prove helpful in examining patients with recurrent symptoms who undergo repeated MR scanning. When an abnormally bright, diffuse MR signal intensity on STIR imaging is seen more than 6 months after an original injury, such abnormal signal intensity is likely to represent new injury. RP Slocum, KA (reprint author), USN,MED CTR,DEPT CLIN INVEST,DEPT RADIOL,34800 BOB WILSON DR,SAN DIEGO,CA 92134, USA. NR 20 TC 39 Z9 39 U1 0 U2 0 PU AMER ROENTGEN RAY SOC PI RESTON PA 1891 PRESTON WHITE DR, SUBSCRIPTION FULFILLMENT, RESTON, VA 22091 SN 0361-803X J9 AM J ROENTGENOL JI Am. J. Roentgenol. PD MAY PY 1997 VL 168 IS 5 BP 1295 EP 1299 PG 5 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA WV568 UT WOS:A1997WV56800033 PM 9129429 ER PT J AU Borack, JI AF Borack, JI TI A technique for estimating the probability of detecting a nongaming drug user SO AMERICAN STATISTICIAN LA English DT Article DE detection probability; drug urinalysis; nongaming drug user ID URINARY-EXCRETION; HUMANS; BENZOYLECGONINE; COCAINE; SMOKING AB To evaluate the effectiveness of random urinalysis drug testing strategies, it is necessary to estimate the probability of detecting drug users, that is, the probability that users will be selected for drug testing and test positive. Methodologies were developed for estimating the probability of detecting nongaming drug users under a variety of drug wear-off models. It was observed that the probability of detection is proportional and the expected number of months until detection is inversely proportional to the monthly test rate. RP Borack, JI (reprint author), USN,CTR PERSONNEL RES & DEV,SAN DIEGO,CA 92152, USA. NR 12 TC 1 Z9 1 U1 0 U2 0 PU AMER STATISTICAL ASSOC PI ALEXANDRIA PA 1429 DUKE ST, ALEXANDRIA, VA 22314 SN 0003-1305 J9 AM STAT JI Am. Stat. PD MAY PY 1997 VL 51 IS 2 BP 134 EP 136 DI 10.2307/2685404 PG 3 WC Statistics & Probability SC Mathematics GA WY249 UT WOS:A1997WY24900009 ER PT J AU Bacon, GS Lyons, TR Wood, SH AF Bacon, GS Lyons, TR Wood, SH TI Dyclonine hydrochloride for airway anesthesia: Awake endotracheal intubation in a patient with suspected local anesthetic allergy SO ANESTHESIOLOGY LA English DT Article DE anesthesia, intratracheal, awake intubation; anesthetics, local, dyclonine; drug hypersensitivity, local anesthetics C1 NEWPORT HOSP,NEWPORT,RI. RP Bacon, GS (reprint author), USN HOSP,DEPT ANESTHESIOL,1 RIGGS RD,NEWPORT,RI, USA. NR 12 TC 5 Z9 5 U1 0 U2 2 PU LIPPINCOTT-RAVEN PUBL PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 SN 0003-3022 J9 ANESTHESIOLOGY JI Anesthesiology PD MAY PY 1997 VL 86 IS 5 BP 1206 EP 1207 DI 10.1097/00000542-199705000-00023 PG 2 WC Anesthesiology SC Anesthesiology GA WX859 UT WOS:A1997WX85900024 PM 9158369 ER PT J AU Murnane, JE AF Murnane, JE TI Naval Wasps active SO ANNALS OF ALLERGY ASTHMA & IMMUNOLOGY LA English DT Letter RP Murnane, JE (reprint author), USN,CDR,MC,PORTSMOUTH,VA 23708, USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER COLL ALLERGY ASTHMA IMMUNOLOGY PI ARLINGTON HTS PA 85 WEST ALGONQUIN RD SUITE 550, ARLINGTON HTS, IL 60005 SN 1081-1206 J9 ANN ALLERG ASTHMA IM JI Ann. Allergy Asthma Immunol. PD MAY PY 1997 VL 78 IS 5 BP 524 EP 524 PG 1 WC Allergy; Immunology SC Allergy; Immunology GA WZ986 UT WOS:A1997WZ98600014 ER PT J AU SteelGoodwin, L Kuhlman, KJ Miller, C Pace, MD Carmichael, AJ AF SteelGoodwin, L Kuhlman, KJ Miller, C Pace, MD Carmichael, AJ TI Effects of reactive oxygen and nitrogen species induced by ammonium dinitramide decomposition in aqueous solutions of deoxyribose nucleic acid SO ANNALS OF CLINICAL AND LABORATORY SCIENCE LA English DT Article AB Ammonium dinitramide (ADN), a potential rocket fuel, decomposes in water forming NO,. The chemistry of this ADN-released NO, in oxygenated biological systems is complex both in the number of potential chemical species and in the number of parallel and consecutive reactions that can theoretically occur. High-pressure liquid chromatography (HPLC) studies revealed ADN fragmented deoxyribose nucleic acid (DNA). Damage to DNA standard solutions was caused by at least two major pathways, one arising from reactions of NO2 with oxygen and one arising from a reaction with superoxide (0(2)(-.)). The radical species generated when ADN is incubated with standard solutions of DNA, pH 7.5, in the presence of the spin trap agent n-tert-butyl-alpha-nitrone (PEN) was compared with the PEN-radical adducts generated in the presence of ADN and 0(2)(-.) or of ADN and hydrogen peroxide (H2O2). The ADN-induced PEN radical adducts increased linearly over the 90-minute study period. The values of peak intensity in the presence of 0(2)(-.) and in the presence of H2O2, were 828% and 7.08%, respectively, of the ADN-induced radicals alone. The synergistic effect of ADN with 0(2)(-) may provide an understanding of the sensitivity of the rat blastocyst to ADN at the preimplantation stage of development and the lack of toxicity in in vivo studies in tissues high in catalase. C1 ARMSTRONG LAB,TRISERV TOXICOL,WRIGHT PATTERSON AFB,OH 45433. MANTECH ENVIRONM INC,DAYTON,OH 45431. WALTER REED ARMY TOXICOL DETACHMENT,DAYTON,OH 45431. USN,RES LAB,WASHINGTON,DC 20332. ARMED FORCES RADIOBIOL RES INST,BETHESDA,MD 20332. NR 20 TC 1 Z9 1 U1 0 U2 0 PU INST CLINICAL SCIENCE INC PI PHILADELPHIA PA 1833 DELANCEY PLACE, PHILADELPHIA, PA 19103 SN 0091-7370 J9 ANN CLIN LAB SCI JI Ann. Clin. Lab. Sci. PD MAY-JUN PY 1997 VL 27 IS 3 BP 236 EP 245 PG 10 WC Medical Laboratory Technology SC Medical Laboratory Technology GA WX121 UT WOS:A1997WX12100010 PM 9142377 ER PT J AU Mueller, JG Devereux, R Santavy, DL Lantz, SE Willis, SG Pritchard, PH AF Mueller, JG Devereux, R Santavy, DL Lantz, SE Willis, SG Pritchard, PH TI Phylogenetic and physiological comparisons of PAH-degrading bacteria from geographically diverse soils SO ANTONIE VAN LEEUWENHOEK INTERNATIONAL JOURNAL OF GENERAL AND MOLECULAR MICROBIOLOGY LA English DT Article DE 16S rRNA; Biolog(TM); bioremediation; phenotype; phospholipid ester-linked fatty acid (GC-FAME); phylogeny; polycyclic aromatic hydrocarbons (PAHs); taxonomy ID POLYCYCLIC AROMATIC-HYDROCARBONS; CREOSOTE-CONTAMINATED MATERIALS; BIOLOGICAL TREATMENT PROCESSES; BENCH-SCALE EVALUATION; GEN-NOV; PHASE BIOREMEDIATION; DEEP SUBSURFACE; COMB-NOV; SPHINGOMONAS; PHENANTHRENE AB The diversity of bacteria isolated from creosote- contaminated soils in the United States, Norway, and Germany was determined by comparing their ability to degrade polycyclic aromatic hydrocarbons (PAHs), their phospholipid ester-linked fatty acid (GC-FAME) profiles, sole carbon source utilization patterns (Biolog(TM) assays(dagger)), and 16S rRNA sequences. Bacteria were initially obtained by enrichment with phenanthrene and fluoranthene. Many were capable of degrading a broad range of the PAHs found in creosote. Phenanthrene- or fluoranthene-degraders were abundant in most of the soils tested. Several of the fluoranthene-degrading isolates clustered with Sphingomonas (formerly Pseudomonas) paucimobilis strain EPA505 in the GC-FAME and Biolog(TM) analyses and three of the isolates examined by 16S rRNA sequence comparisons showed a close relationship with Sphingomonas. In addition, the Sphingomonas strains showed the most extensive degradation of 4- & 5-ring PAHs in creosote. Burkholderia cepacia strains isolated on phenanthrene from PAH-contaminated soils had limited ability to attack higher molecular weight PAHs either individually or in creosote. Thus, PAH degradation capabilities appeared to be associated with members of certain taxa, independent of the origin of the soils from which the bacteria were isolated. C1 US EPA, NATL HLTH & ENVIRONM EFFECTS RES LAB, GULF ECOL DIV, WASHINGTON, DC 20460 USA. UNIV MASSACHUSETTS, AMHERST, MA 01003 USA. USN, RES LAB, WASHINGTON, DC 20375 USA. RP Mueller, JG (reprint author), SBP TECHNOL INC, 1 SABINE ISL DR, GULF BREEZE, FL 32561 USA. NR 71 TC 122 Z9 126 U1 0 U2 7 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0003-6072 J9 ANTON LEEUW INT J G JI Antonie Van Leeuwenhoek PD MAY PY 1997 VL 71 IS 4 BP 329 EP 343 DI 10.1023/A:1000277008064 PG 15 WC Microbiology SC Microbiology GA XD931 UT WOS:A1997XD93100006 PM 9195008 ER PT J AU Broussard, PR Qadri, SB Browning, VM Cestone, VC AF Broussard, PR Qadri, SB Browning, VM Cestone, VC TI X-ray photoemission spectroscopy of La0.67Ca0.33MnO3 films SO APPLIED SURFACE SCIENCE LA English DT Article ID THIN-FILMS; LA1-XSRXMNO3; YBA2CU3O7-X AB We have performed X-ray photoemission spectroscopy (XPS) on thin films of (001) and (200) oriented La0.67Ca0.33MnO3 grown on (100) and (110) SrTiO3 substrates by off-axis sputtering. The films were examined by XPS without exposing them to air. We have compared the core levels and the valence spectra between the two different orientations, as well as after the effects of air exposure and annealing in UHV. We find that the surfaces are very stable against exposure to air. Comparing the measured intensity ratios to a model for the uniform termination of the film shows the terminating layer to be MnO2 for both the (001) and (200) oriented La0.67Ca0.33MnO3 films. RP Broussard, PR (reprint author), USN,RES LAB,CODE 6344,WASHINGTON,DC 20375, USA. NR 16 TC 22 Z9 22 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-4332 J9 APPL SURF SCI JI Appl. Surf. Sci. PD MAY PY 1997 VL 115 IS 1 BP 80 EP 86 DI 10.1016/S0169-4332(96)00848-3 PG 7 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA WX178 UT WOS:A1997WX17800011 ER PT J AU Strand, KA Kallarakal, VV AF Strand, KA Kallarakal, VV TI Photovisual magnitude differences for 169 double stars SO ASTRONOMICAL JOURNAL LA English DT Article AB Photovisual magnitude differences determined from multi-exposure photographic plates for 169 double stars are presented. The separations range from 1.5 '' to 113 '', and the photovisual magnitude differences vary from 0.03 to 6.14 magnitudes. The internal mean error of a single magnitude difference estimate is +/- 0.064 magnitude. C1 USN OBSERV,WASHINGTON,DC 20392. NR 3 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAY PY 1997 VL 113 IS 5 BP 1884 EP 1887 DI 10.1086/118400 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA WX752 UT WOS:A1997WX75200037 ER PT J AU Zacharias, N AF Zacharias, N TI Astrometric quality of the USNO CCD astrograph (UCA) SO ASTRONOMICAL JOURNAL LA English DT Article ID STARS AB The USNO 8-inch astrograph has been equipped with a Kodak 1536X1024 pixel CCD since 1995 June, operating in a 570-650 nm bandpass. With 3-minute exposures well exposed images are obtained in the magnitude range R approximate to 8.5-13.5(m). An astrometric precision of 10 to 15 mas for those stars is estimated from frame-to-frame comparisons. External comparisons reveal an accuracy of about 15 mas for those stars in a 20' field of view. For fainter stars, the error budget is dominated by the SM ratio, reaching approximate to 100 mas at R=16(m) under good observing conditions. (C) 1997 American Astronomical Society. C1 USN OBSERV,WASHINGTON,DC 20392. NR 22 TC 12 Z9 12 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAY PY 1997 VL 113 IS 5 BP 1925 EP 1932 DI 10.1086/118407 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA WX752 UT WOS:A1997WX75200044 ER PT J AU Widing, KG AF Widing, KG TI Emerging active regions on the sun and the photospheric abundance of neon SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun, abundances; Sun, activity ID ELEMENTAL ABUNDANCES; SOLAR ATMOSPHERE; OXYGEN; FLARE; MAGNESIUM; SPECTRUM; SKYLAB AB Early work on Skylab spectroheliograms showed that deep-lying impulsive flares and newly emerged active regions showed a high relative abundance of neon, thought to be representative of the unknown neon abundance in the underlying photosphere. In pursuit of this idea a survey of emerging magnetic flux sequences on Skylab spectroheliograms (300-600 Angstrom) has been made, and from these the Ne/Mg abundance ratio has been derived by combining plots of the ion differential emission measures, From the initial phase of five emerging flux sequences a stable value of the Ne/Mg abundance ratio equal to 3.16 +/- 0.07 has been determined. Normalizing this to the well-determined abundance of magnesium, the photospheric abundance of neon is log Neon = 8.08 +/- 0.06, log H = 12. This result is compared with previous estimates which used ''local galactic values'' as a proxy for the unknown neon abundance. The present results are also compared with a slightly larger Ne/Mg ratio of 3.6 +/- 0.4 (log Neon = 8.14) observed in a deep-lying impulsive flare, also thought to expose a sample of photospheric material. RP Widing, KG (reprint author), USN,RES LAB,EO HULBURT CTR SPACE RES,WASHINGTON,DC 20375, USA. NR 26 TC 28 Z9 28 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 1997 VL 480 IS 1 BP 400 EP & DI 10.1086/303947 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA WW282 UT WOS:A1997WW28200039 ER PT J AU Blair, PJ Riley, JL Carroll, RG StLouis, DC Levine, BL Saha, B Lee, KP Perrin, PJ Harlan, DM June, CH AF Blair, PJ Riley, JL Carroll, RG StLouis, DC Levine, BL Saha, B Lee, KP Perrin, PJ Harlan, DM June, CH TI CD28 co-receptor signal transduction in T-cell activation SO BIOCHEMICAL SOCIETY TRANSACTIONS LA English DT Article; Proceedings Paper CT 660th Meeting Biochemical-Society / British-Society-Immunology CY DEC 10-13, 1996 CL HARROGATE, ENGLAND SP Biochem Soc, Brit Soc Immunol ID HUMAN LYMPHOCYTES-T; TRANSGENIC MICE; HIV-1 INFECTION; CTLA-4; APOPTOSIS; ANTIGEN; COSTIMULATION; REPLICATION; DEATH; GENE C1 HENRY M JACKSON FDN ADVANCEMENT MIL MED,ROCKVILLE,MD 20850. WALTER REED ARMY MED CTR,DIV RETROVIROL,ROCKVILLE,MD 20850. UNIFORMED SERV UNIV HLTH SCI,DEPT MED,BETHESDA,MD 20814. UNIFORMED SERV UNIV HLTH SCI,DEPT MOL & CELL BIOL,BETHESDA,MD 20814. RP Blair, PJ (reprint author), USN,MED RES INST,IMMUNE CELL BIOL PROGRAM,1809 WISCONSIN AVE,BETHESDA,MD 20814, USA. RI Levine, Bruce/D-1688-2009; OI Riley, James/0000-0002-1057-576X NR 59 TC 11 Z9 11 U1 0 U2 1 PU PORTLAND PRESS PI LONDON PA 59 PORTLAND PLACE, LONDON, ENGLAND W1N 3AJ SN 0300-5127 J9 BIOCHEM SOC T JI Biochem. Soc. Trans. PD MAY PY 1997 VL 25 IS 2 BP 651 EP 657 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA XB637 UT WOS:A1997XB63700060 PM 9191174 ER PT J AU Kuznetsov, YG Malkin, AJ Land, TA DeYoreo, JJ Barba, AP Konnert, J McPherson, A AF Kuznetsov, YG Malkin, AJ Land, TA DeYoreo, JJ Barba, AP Konnert, J McPherson, A TI Molecular resolution imaging of macromolecular crystals by atomic force microscopy SO BIOPHYSICAL JOURNAL LA English DT Article ID BEAN CANAVALIA-ENSIFORMIS; TOBACCO MOSAIC-VIRUS; 3-DIMENSIONAL STRUCTURE; IN-SITU; GROWTH; PROTEIN; MECHANISMS; CRYSTALLIZATION AB Atomic force microscopy (AFM) images at the molecular level have been obtained for a number of different protein and virus crystals. They can be utilized in some special cases to obtain information useful to crystal structure analyses by x-ray diffraction. In particular, questions of space group enantiomer, the packing of molecules within a unit cell, the number of molecules per asymmetric unit, and the dispositions of multiple molecules within the asymmetric unit may be resolved. In addition, because of the increasing sensitivity and resolution of the AFM technique, some molecular features of very large asymmetric units may be within reach. We describe here high-resolution studies, using AFM, to visualize individual molecules and viruses in their crystal lattices. These investigations included fungal lipase, lysozyme, thaumatin, canavalin, and satellite tobacco mosaic virus (STMV). C1 UNIV CALIF RIVERSIDE,DEPT BIOCHEM,RIVERSIDE,CA 92521. LAWRENCE LIVERMORE NATL LAB,DEPT CHEM & MAT SCI,LIVERMORE,CA 94550. USN,RES LAB,STRUCT MATTER LAB,WASHINGTON,DC 20375. NR 24 TC 79 Z9 79 U1 1 U2 13 PU BIOPHYSICAL SOCIETY PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD MAY PY 1997 VL 72 IS 5 BP 2357 EP 2364 PG 8 WC Biophysics SC Biophysics GA WV984 UT WOS:A1997WV98400044 PM 9129839 ER PT J AU Hembree, L Brand, S Mayse, WC Cianciolo, M Soderberg, B AF Hembree, L Brand, S Mayse, WC Cianciolo, M Soderberg, B TI Incorporation of a cloud simulation into a flight mission rehearsal system: Prototype demonstration SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article AB One environmental parameter that has a large impact on aircraft missions for the U.S. military is clouds. This article describes an initial attempt to incorporate physically consistent clouds into a flight mission rehearsal system. A cloud model is used to generate cloud information that is visually incorporated into the PowerScene mission rehearsal system. PowerScene incorporates off-the-shelf hardware to provide photo realism to a wide range of applications, including mission planning, previewing, rehearsing, debriefing, and training. Implementation of this approach would allow the user to train in both clear and cloudy conditions and to evaluate the impact of clouds on the mission. The cloud model is briefly described, as are the basic visualization approach, the prototype implementation, and the work remaining to fully integrate these features into PowerScene. C1 CAMBRIDGE RES ASSOC,MCLEAN,VA. TASC INC,READING,MA. LORAL INC,BELLVILLE,WA. RP Hembree, L (reprint author), NAVAL RES LAB,7 GRACE HOPPER AVE,MONTEREY,CA 93943, USA. NR 7 TC 2 Z9 2 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD MAY PY 1997 VL 78 IS 5 BP 815 EP 822 DI 10.1175/1520-0477(1997)078<0815:IOACSI>2.0.CO;2 PG 8 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA XD572 UT WOS:A1997XD57200004 ER PT J AU Swider, KE Merzbacher, CI Hagans, PL Rolison, DR AF Swider, KE Merzbacher, CI Hagans, PL Rolison, DR TI Synthesis of ruthenium dioxide titanium dioxide aerogels: Redistribution of electrical properties on the nanoscale SO CHEMISTRY OF MATERIALS LA English DT Article ID TRANSITION-METAL OXIDES; SOL-GEL CHEMISTRY; LITHIUM INTERCALATION; CATALYSTS AB High-surface area RuO2-TiO2 is an important material for catalytic and power source technologies. To create this mixed oxide as a nanoscale, high-surface-area material, we have synthesized electrically conductive aerogels of RunTi1-nOx via sol-gel chemistry and supercritical drying of the resulting gel. The structural and electrical properties of these aerogels are characterized after annealing using X-ray diffraction, X-ray photoelectron spectroscopy, surface-area measurements, and impedance spectroscopy. Their properties are affected by the nature of the RuCl3 precursor and the initial sol-gel chemistry. Whereas bulk 32 mol % RuO2.TiO2 is an electronic conductor, a dominant ionic response is measured in the impedance of Ru0.32Ti0.68Ox aerogels. This impedance is ascribed to a proton conduction mechanism associated primarily with the hydrous surface of the RuOx component. The electrical conductivity of these Ru0.32Ti0.68Ox aerogels at 25 degrees C increases from 10(-4) S cm(-1) in ambient air to 10(-2) S cm(-1) under an increased partial pressure of water, which is characteristic of a protonic conductor. The electronic conductivity of these aerogels improves with exposure to dry oxygen, which is consistent with the oxidation of Ru3+ surface defects. Synthesizing RuO2-TiO2 as an aerogel-i.e., as high-surface-area, networked interface-accentuates the surface properties of this material. The electrical (electronic + protonic) transport properties of bulk RuO2-TiO2 are redistributed when synthesized as an aerogel. Whereas electronic transport dominates the characteristics of the dense form, the protonic transport of the hydrous oxide surfaces governs the electrical properties of the aerogel. Aerogels provide a useful means to isolate, study, and control the surface of metal oxides. C1 USN,RES LAB,WASHINGTON,DC 20375. NR 47 TC 99 Z9 100 U1 4 U2 37 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD MAY PY 1997 VL 9 IS 5 BP 1248 EP 1255 DI 10.1021/cm960622c PG 8 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA WZ300 UT WOS:A1997WZ30000032 ER PT J AU Baqar, S ElDin, AAMN Scott, DA Bourgeois, AL Mourad, AS Kleinosky, MT Oplinger, MJ Murphy, JR AF Baqar, S ElDin, AAMN Scott, DA Bourgeois, AL Mourad, AS Kleinosky, MT Oplinger, MJ Murphy, JR TI Standardization of measurement of immunoglobulin-secreting cells in human peripheral circulation SO CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY LA English DT Article ID MUCOSAL IMMUNE-SYSTEM; ORAL IMMUNIZATION; BLOOD LYMPHOCYTES; SHIGELLA-SONNEI; ACUTE DIARRHEA; B SUBUNIT; VACCINE; INFECTION; IMMUNOGENICITY; RESPONSES AB A sensitive, and at times the most sensitive, measurement of human vaccine immunogenicity is enumeration of antibody-secreting cells (ASC) in peripheral blood. However, this assay, which is inherently capable of measurement of the absolute number of antigen-specific ASC, is not standardized, Thus, quantitative comparison of results between laboratories is not currently possible, To address this issue, isotype-specific ASC were enumerated from paired fresh and cryopreserved mononuclear cell (MNC) preparations from healthy adult volunteers resident in either the United States (US group) or Egypt (EG group). Analysis of fresh cells from US volunteers revealed mean numbers of ASC per 10(6) MNC of 617, 7,738, and 868 for immunoglobulin M (IgM), IgG, and IgA, respectively, whereas EG volunteers had 2,086, 7,580, and 1,677 ASC/10(6) MNC for the respective isotypes. Cryopreservation resulted in a slight reduction in group mean IgM, IgG, and IgA ASC (maximum reduction in group mean, 14%), but in no instance were results obtained with cryopreserved cells significantly lower than those obtained with fresh cells. To determine if cryopreservation affected the number of bacterial antigen-specific ASC detected, cells from a group of US adult volunteers who received a single oral dose of a mutated Escherichia coli heat-labile enterotoxin (LTR192G) were tested, There was no significant difference (P > 0.05) in the number of antigen-specific IgA or IgG ASC detected between fresh and cryopreserved MNC. The results support the views that ASC assays can be standardized to yield quantitative results and that the methodology can be changed to make the test more practical. C1 UNIV TEXAS,SCH MED,CTR INFECT DIS,HLTH SCI CTR,HOUSTON,TX 77225. USN,MED RES INST,DEPT INFECT DIS,BETHESDA,MD. USA,MED RES INST INFECT DIS,FREDERICK,MD. UNIV ALEXANDRIA,DEPT BACTERIOL,ALEXANDRIA,EGYPT. USN,MED RES UNIT 3,CAIRO,EGYPT. UNIV TEXAS,SCH PUBL HLTH,HOUSTON,TX 77225. UNIV TEXAS,SCH MED,DEPT PEDIAT,DIV INFECT DIS,HOUSTON,TX. NR 29 TC 15 Z9 15 U1 0 U2 0 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 SN 1071-412X J9 CLIN DIAGN LAB IMMUN JI Clin. Diagn. Lab. Immunol. PD MAY PY 1997 VL 4 IS 3 BP 375 EP 379 PG 5 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA WX249 UT WOS:A1997WX24900025 PM 9144380 ER PT J AU Yates, SW Gelfand, MS Handorf, CR AF Yates, SW Gelfand, MS Handorf, CR TI Spontaneous pyomyositis due to Staphylococcus epidermidis SO CLINICAL INFECTIOUS DISEASES LA English DT Article ID TROPICAL PYOMYOSITIS C1 METHODIST HOSP,DEPT INTERNAL MED,MEMPHIS,TN. METHODIST HOSP,DEPT PATHOL,MEMPHIS,TN. RP Yates, SW (reprint author), USN HOSP,DEPT INTERNAL MED,2080 CHILD ST,JACKSONVILLE,FL 32214, USA. OI Yates, Scott/0000-0002-5197-0686 NR 6 TC 5 Z9 5 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 1058-4838 J9 CLIN INFECT DIS JI Clin. Infect. Dis. PD MAY PY 1997 VL 24 IS 5 BP 1016 EP 1017 PG 2 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA WX257 UT WOS:A1997WX25700056 PM 9142821 ER PT J AU Kwon, YW Liu, CT AF Kwon, YW Liu, CT TI Study of damage evolution in composites using damage mechanics and micromechanics SO COMPOSITE STRUCTURES LA English DT Article; Proceedings Paper CT 9th International Conference on Composite Structures (ICCS/9) CY SEP, 1997 CL UNIV PAISLEY, PAISLEY, SCOTLAND SP Univ Paisley, Renfrewshire Enterprise, Renfrewshire Council, Chivas, Glenlivet Grp, USAF, European Off Aerospace Res & Dev, USA, Res Dev & Standardisat Grp, UK HO UNIV PAISLEY ID LAMINATED COMPOSITES; FIBROUS COMPOSITES; STRESS-CONCENTRATIONS; DELAMINATION; CRITERIA; MODEL AB A numerical modeling technique was presented to simulate, predict and evaluate progressive damage or failure in a composite structure subjected to an external loading. To this end, a micro/macromechanical approach was proposed along with damage mechanics at the microlevel. The micro/macromechanical model utilized both the macromechanical analysis and the micromechanical analysis in tandem. The continuum damage mechanics was applied to the microlevel stresses-strains in order to predict damage evolution in a composite structure from the initiation of damage through to complete failure of the structure. Crack initiation and growth in a particulate composite with stress concentration was simulated using the proposed technique, and the results were compared to experimental data. The comparison showed a very good agreement. (C) 1997 Elsevier Science Ltd. C1 USN, Postgrad Sch, Dept Mech Engn, Monterey, CA 93943 USA. Phillips Lab, Edward AFB, CA USA. RP Kwon, YW (reprint author), USN, Postgrad Sch, Dept Mech Engn, Monterey, CA 93943 USA. NR 31 TC 16 Z9 16 U1 1 U2 4 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0263-8223 J9 COMPOS STRUCT JI Compos. Struct. PD MAY-AUG PY 1997 VL 38 IS 1-4 BP 133 EP 139 DI 10.1016/S0263-8223(97)00049-4 PG 7 WC Materials Science, Composites SC Materials Science GA YP209 UT WOS:000071253500016 ER PT J AU Kwon, YW Yoon, SH Sistare, PJ AF Kwon, YW Yoon, SH Sistare, PJ TI Compressive failure of carbon-foam sandwich composites with holes and/or partial delamination SO COMPOSITE STRUCTURES LA English DT Article; Proceedings Paper CT 9th International Conference on Composite Structures (ICCS/9) CY SEP, 1997 CL UNIV PAISLEY, PAISLEY, SCOTLAND SP Univ Paisley, Renfrewshire Enterprise, Renfrewshire Council, Chivas, Glenlivet Grp, USAF, European Off Aerospace Res & Dev, USA, Res Dev & Standardisat Grp, UK HO UNIV PAISLEY ID POSTBUCKLING BEHAVIOR; PANELS; HONEYCOMB; SKINS; BEAMS AB Compression failure of sandwich composites made of fibrous carbon-epoxy skins and foam core was investigated using an experimental study. The sandwich specimens had holes and/or partial delamination between the skin and core, and they were subjected to compressive edge loading. Different core thicknesses of sandwich specimens were considered, and hole sizes and locations were varied to examine their effects on the compression failure. The study also included compression of delaminated specimens. In order to better understand the failure mechanism, a numerical study was also conducted. Major modes of failure were core shearing, delamination and skin fracture. Depending on the given parameter, the failure mode was different. The study examined the transition of the failure mode from one kind to another depending on the variation in the parameters such as delamination and hole size and location. (C) 1997 Elsevier Science Ltd. C1 USN, Postgrad Sch, Dept Mech Engn, Monterey, CA 93943 USA. Kumoh Natl Univ Technol, Dept Mech Engn, Kumoh, South Korea. RP Kwon, YW (reprint author), USN, Postgrad Sch, Dept Mech Engn, Monterey, CA 93943 USA. NR 14 TC 12 Z9 18 U1 0 U2 4 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0263-8223 J9 COMPOS STRUCT JI Compos. Struct. PD MAY-AUG PY 1997 VL 38 IS 1-4 BP 573 EP 580 DI 10.1016/S0263-8223(97)00093-7 PG 8 WC Materials Science, Composites SC Materials Science GA YP209 UT WOS:000071253500059 ER PT J AU Lewis, T AF Lewis, T TI Absorb and extend: Resistance is futile! SO COMPUTER LA English DT Article RP Lewis, T (reprint author), USN,POSTGRAD SCH,CODE CS,MONTEREY,CA 93943, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 SN 0018-9162 J9 COMPUTER JI Computer PD MAY PY 1997 VL 30 IS 5 BP 112 EP & PG 4 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA WW863 UT WOS:A1997WW86300030 ER PT J AU Cole, JB AF Cole, JB TI High accuracy solution of Maxwell's equations using nonstandard finite differences SO COMPUTERS IN PHYSICS LA English DT Article AB We introduce a new finite-difference time-domain algorithm to directly solve Maxwell's equations based on nonstandard finite differences. This algorithm is some 10,000 times more accurate than the standard one on a coarse grid. Although computational load per grid point is greater, it is more than offset by a large reduction in the total number of grid points needed to solve a given problem. In addition, algorithm stability is greater, so that the number of iterations needed is also reduced. While optimum performance is achieved at a fixed frequency, the accuracy is still higher than that of the standard-algorithm over moderate bandwidths. The algorithm is implemented in Fortran 90 and can easily model spatially variant media and irregular boundaries. By displaying one. or more fields per wave period we obtain on-line movielike visualizations of the electromagnetic fields while the computation is running. (C) 1997 American Institute of Physics. C1 USN,RES LAB,WASHINGTON,DC 20375. RP Cole, JB (reprint author), UNIV TSUKUBA,INST INFORMAT SCI & ELECT,TSUKUBA,IBARAKI 305,JAPAN. NR 8 TC 18 Z9 18 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0894-1866 J9 COMPUT PHYS JI Comput. Phys. PD MAY-JUN PY 1997 VL 11 IS 3 BP 287 EP 292 DI 10.1063/1.168620 PG 6 WC Computer Science, Interdisciplinary Applications; Physics, Multidisciplinary; Physics, Mathematical SC Computer Science; Physics GA XA317 UT WOS:A1997XA31700017 ER PT J AU Bakaltcheva, I Rudolph, AS Spargo, BJ AF Bakaltcheva, I Rudolph, AS Spargo, BJ TI Shape stabilizing agents protect erythrocytes against freeze-thaw damage SO CRYO-LETTERS LA English DT Article DE erythrocytes; shape stabilizing agents; cryoprotection; lectins; SH oxidizing agents ID WHEAT-GERM-AGGLUTININ; MEMBRANE; DEFORMABILITY; CELLS AB In this work we demonstrate that physicochemical modification of the erythrocyte membrane by shape stabilizing agents increases cryostability. Three different classes of shape stabilizing agents were examined for their cryoprotective action: the lectins (wheat germ agglutinin and concanavalin A), sulfhydryl oxidizing agents (diamide and N-ethylmaleimide) and chemical fixatives (glutaraldehyde). All classes of agents reduced freeze-thaw damage after freezing erythrocytes to -20 degrees C in a concentration and time dependent manner. The cryoprotectant action of these agents was compared with their ability to stabilize erythrocyte shape and affect membrane deformability. All shape stabilizing agents with the exeption of concanavalin A induced a significant decrease in membrane deformability. Anti-glycophorin antibody and Phaseolus vulgaris lectin increased membrane rigidity but did not act as shape stabilizing agents or cryoprotectants. Thus, the ability to alter membrane deformability, may not by itself result in shape stabilization or cryoprotection. The ability to stabilize red cell shape may however result in increased cryostability. C1 USN,RES LAB,CTR BIOMOL SCI & ENGN,WASHINGTON,DC 20375. GEOCENTERS INC,FT WASHINGTON,MD 20744. NR 27 TC 2 Z9 2 U1 0 U2 0 PU CRYO LETTERS PI CAMBRIDGE PA 7 WOOTTON WAY, CAMBRIDGE, CAMBS, ENGLAND CB3 9LX SN 0143-2044 J9 CRYO-LETT JI Cryo-Lett. PD MAY-JUN PY 1997 VL 18 IS 3 BP 165 EP 178 PG 14 WC Biology; Physiology SC Life Sciences & Biomedicine - Other Topics; Physiology GA XC295 UT WOS:A1997XC29500006 ER PT J AU Reed, RP Golda, M AF Reed, RP Golda, M TI Cryogenic composite supports: A review of strap and strut properties SO CRYOGENICS LA English DT Article DE composites; cryogenic structural supports; mechanical properties; thermal properties ID SPACE AB The properties of fibre-reinforced composite straps and struts that a re used for thermal isolation and mechanical support of cryogenic systems are reviewed. The review includes compilation and discussion of the mechanical (tension, compression, fatigue) and thermal (contraction, conductivity, specific heat) aspects of both structures. The role of fibre lay-up is discussed, and the two types of support modes are compared. (C) 1997 Elsevier Science Ltd. C1 USN,ELECT MACHINERY TECHNOL BRANCH,MACHINERY RES & DEV DIRECTORATE,CTR SURFACE WARFARE,ANNAPOLIS,MD 21402. RP Reed, RP (reprint author), CRYOGEN MAT INC,2625 LLIFF,BOULDER,CO 80303, USA. NR 19 TC 25 Z9 35 U1 3 U2 7 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD MAY PY 1997 VL 37 IS 5 BP 233 EP 250 DI 10.1016/S0011-2275(97)00004-0 PG 18 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA XD450 UT WOS:A1997XD45000001 ER PT J AU Kelly, TL Mitler, MM Bonnet, MH AF Kelly, TL Mitler, MM Bonnet, MH TI Sleep latency measures of caffeine effects during sleep deprivation SO ELECTROENCEPHALOGRAPHY AND CLINICAL NEUROPHYSIOLOGY LA English DT Article DE sleep latency; maintenance of wakefulness test; sleep deprivation; stimulants; caffeine ID PROPHYLACTIC NAPS; WAKEFULNESS TEST; PERFORMANCE; MAINTENANCE; NARCOLEPSY; ALERTNESS; DISORDERS; EFFICACY; ABILITY; NIGHT AB Studies of stimulants during sleep deprivation have used performance assessment batteries (PABs) and occasionally the multiple sleep latency test (MSLT) as measures. Another type of sleep latency test, the maintenance of wakefulness test (MWT), assesses ability to remain awake without assistance, rather than ability to go to sleep. The MWT previously has not been used in studies of stimulants during sleep deprivation. This study of caffeine during 64 h without sleep included a PAB, the MSLT, and a single MWT trial per day. The PAB and the MSLT were sensitive to caffeine effects during the first 24 h without sleep. The MWT demonstrated that caffeine improved ability to remain awake even after 2 nights of sleep deprivation. Ability to go to sleep and ability to stay awake during sleep deprivation appear to be affected differently by caffeine. PAB testing may fail to detect this stimulant effect because technicians prevent subjects from nodding off during PAB testing, an external support not available to subjects during the MWT and also not available in many real-world work environments. The MWT was more Sensitive to stimulant amelioration of sleep-deprivation effects. The findings need to be validated with MWTs at other times of day and with other stimulants. (C) 1997 Elsevier Science Ireland Ltd. C1 SCRIPPS CLIN,SAN DIEGO,CA. DAYTON DEPT VET AFFAIRS MED CTR,DAYTON,OH. RP Kelly, TL (reprint author), USN,HLTH RES CTR,POB 85122,SAN DIEGO,CA 92186, USA. NR 24 TC 16 Z9 17 U1 1 U2 1 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0013-4694 J9 ELECTROEN CLIN NEURO JI Electroencephalogr. Clin. Neurophysiol. PD MAY PY 1997 VL 102 IS 5 BP 397 EP 400 DI 10.1016/S0921-884X(97)96135-X PG 4 WC Engineering, Biomedical; Clinical Neurology SC Engineering; Neurosciences & Neurology GA XF446 UT WOS:A1997XF44600003 PM 9191583 ER PT J AU Mushrush, GW Beal, EJ Goodell, ML Slone, JE McClelland, DB Mose, DG AF Mushrush, GW Beal, EJ Goodell, ML Slone, JE McClelland, DB Mose, DG TI Determination of the middle distillate fuel potential of shale oil SO ENERGY SOURCES LA English DT Article DE jet fuel; middle distillate; pyrolysis; shale oil AB Oil shale deposits constitute a large reserve of oil stocks. These immense deposits can potentially be used most conveniently as a source of middle distillate fuels such as jet fuel. The characteristic of the jet fuel distillation cut is a high n-alkane content. Jet fuels require a large n-alkane fraction in order to simultaneously meet both the freezing point and flash point requirements. The conditions reported in this study mimic the refining process known as delayed coking. This study focuses on a method for the rapid determination of the middle distillate fuel potential of shale-derived fuels. C1 USN,RES LAB,FUELS SECT,NAVY TECHNOL CTR SAFETY & SURVIVABIL,WASHINGTON,DC 20375. RP Mushrush, GW (reprint author), GEORGE MASON UNIV,DEPT CHEM,MSN 3E2,FAIRFAX,VA 22030, USA. NR 12 TC 0 Z9 0 U1 0 U2 1 PU TAYLOR & FRANCIS PI BRISTOL PA 1900 FROST ROAD, SUITE 101, BRISTOL, PA 19007-1598 SN 0090-8312 J9 ENERG SOURCE JI Energy Sources PD MAY PY 1997 VL 19 IS 4 BP 369 EP 377 DI 10.1080/00908319708908856 PG 9 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA WZ740 UT WOS:A1997WZ74000005 ER PT J AU Bart, JC Judd, LL Hoffman, KE Wilkins, AM Kusterbeck, AW AF Bart, JC Judd, LL Hoffman, KE Wilkins, AM Kusterbeck, AW TI Application of a portable immunosensor to detect the explosives TNT and RDX in groundwater samples SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID THIN-LAYER CHROMATOGRAPHY; PERFORMANCE LIQUID-CHROMATOGRAPHY; COLUMN GAS-CHROMATOGRAPHY; TANDEM MASS-SPECTROMETRY; THERMAL-ENERGY ANALYZER; TRACE ANALYSIS; BIODEGRADATION PRODUCTS; WATER; 2,4,6-TRINITROTOLUENE; SOIL AB In the summer of 1995, the EPA conducted a performance evaluation of several commercially available test kits and two prototype biosensor devices to determine if any of these technologies were feasible as an alternative to the standard EPA SW-846 Method 8330 test for explosives in aqueous samples. These on-site assays offer potential advantages in cost, assay time, and convenience over the traditional analysis via high-performance liquid chromatography (HPLC). The continuous flow immunosensor (CFI) was one of the biosensors participating in this trial, which took place at two Superfund sites located on military bases. The CFI uses a small column filled with plastic beads containing immobilized antibodies against the explosive being assayed and a fluorescent dye-labeled explosive analog. Detection occurs when the native explosive in the sample is swept into the column and displaces some of the dye-labeled analog, which is quantified via a fluorometer. Results from these tests showed that the CFI could produce data comparable to HPLC with no significant problems with cross-reactivity of the antibodies against other explosives or their breakdown products. C1 USN,RES LAB,CTR BIOMOL SCI & ENGN,BIOSENSORS & BIOMAT LAB,WASHINGTON,DC 20375. NR 40 TC 44 Z9 44 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD MAY PY 1997 VL 31 IS 5 BP 1505 EP 1511 DI 10.1021/es960777l PG 7 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA WW948 UT WOS:A1997WW94800052 ER PT J AU Garcia, SMF Jensen, S AF Garcia, SMF Jensen, S TI The p version of mixed finite element methods for parabolic problems SO ESAIM-MATHEMATICAL MODELLING AND NUMERICAL ANALYSIS-MODELISATION MATHEMATIQUE ET ANALYSE NUMERIQUE LA English DT Article ID STABILITY AB We investigate a parabolic problem from the point of view of stability and approximation properties of increasing order mixed (in space) finite element methods. Previous estimates for the Raviart-Thomas projection are proven to be sharp. We analyze the effects of mixed finite element discretization in space to present transient error estimates (for semidiscrete mixed finite element methods). The results in this paper (submitted in Oct. 1993) complement the results already published in [6-8]. C1 UNIV MARYLAND BALTIMORE CTY, DEPT MATH, BALTIMORE, MD 21250 USA. RP USN ACAD, DEPT MATH, ANNAPOLIS, MD 21402 USA. NR 17 TC 0 Z9 0 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0764-583X EI 1290-3841 J9 ESAIM-MATH MODEL NUM JI ESAIM-Math. Model. Numer. Anal.-Model. Math. Anal. Numer. PD MAY PY 1997 VL 31 IS 3 BP 303 EP 326 PG 24 WC Mathematics, Applied SC Mathematics GA WZ959 UT WOS:A1997WZ95900001 ER PT J AU Taskintuna, I Banker, AS Rao, NA Wiley, CA FloresAguilar, M Munguia, D BergeronLynn, G DeClercq, E Keefe, K Freeman, WR AF Taskintuna, I Banker, AS Rao, NA Wiley, CA FloresAguilar, M Munguia, D BergeronLynn, G DeClercq, E Keefe, K Freeman, WR TI An animal model for cidofovir (HPMPC) toxicity: Intraocular pressure and histopathologic effects SO EXPERIMENTAL EYE RESEARCH LA English DT Article; Proceedings Paper CT 1995 Annual Meeting of the Association-for-Research-in-Vision-and-Ophthalmology CY MAY 14-19, 1995 CL FT LAUDERDALE, FL SP Assoc Res Vis & Ophthalmol DE AIDS; antiviral drugs; drug delivery; cidofovir (HPMPC) ID CYTOMEGALO-VIRUS RETINITIS; DIHYDROXY PROPOXYMETHYL GUANINE; ACQUIRED-IMMUNODEFICIENCY-SYNDROME; IMMUNE-DEFICIENCY-SYNDROME; INTRAVITREAL GANCICLOVIR; SUSTAINED-RELEASE; FOSCARNET THERAPY; DNA-SYNTHESIS; AIDS; (S)-1-(3-HYDROXY-2-PHOSPHONYLMETHOXYPROPYL)CYTOSINE AB Intravitreal cidofovir has been shown to be a long acting and highly efficacious treatment for CMV retinitis: however decrease in IOP is an adverse effect. We wanted to determine the effect of cidofovir on intraocular pressure (IOP) ih the guinea pig, and rabbit eye to develop an animal model of cidofovir induced ocular hypotony and to study the histopathology of this toxicity. Twenty-eight guinea pig eyes were injected with cidofovir yielding final intravitreal concentrations of 25, 200, 625 and 2000 mu g ml(-1). Eighteen eyes of pigmented rabbits were injected with cidofovir yielding final intravitreal concentrations of 625 and 2000 mu g ml(-1). A carefully calibrated low volume displacement manometer system using a micro-transducer was used to determine the IOP measurements in the guinea pig and rabbit eyes. Histology was evaluated using light and electron microscopy. Injection of 6.25 mu g of cidofovir intravitreally (vitreous concentration of 25 mu g ml(-1)) is the highest non-toxic dose in the guinea pig; the IOP was unchanged at two and four weeks after injection with this dose; histologically the eyes were normal. A single injection of 50 mu g of cidofovir intravitreally (vitreous concentration of 200 mu g ml(-1)) caused a long lasting (9.3 mmHg) decrease in IOP (approximately 50% of baseline). At this dose there were only mild and variable histologic changes in the ciliary body and the retina. Higher doses of 156.25 mu g and 500 mu g of cidofovir (vitreous concentrations of 625, and 2000 mu g ml(-1), respectively) caused moderate to severe ciliary body and retinal changes, In rabbit eyes there was a mild but statistically insignificant pressure drop with doses of 875 mu g cidofovir intravitreally (vitreous concentration of 625 mu g ml(-1)); retina was within normal limits after injection with this dose, there were mild changes in the ciliary body. There was a total destruction of ciliary body and loss of nonpigmented epithelial cells with injections of 2800 mu g of cidofovir intravitreally (vitreous concentration of 2000 mu g ml(-1)); retina was relatively well preserved. The guinea pig eye shows similar reduction in IOP and ciliary body changes as are seen in the human eye after intravitreal cidofovir and also appears to have a similar dose-response curve. However, the reduction of IOP caused by cidofovir occurs in the guinea pig eye at a concentration 40 times higher than was observed in the human eye. (C) 1997 Academic Press Limited. C1 UNIV CALIF SAN DIEGO,SHILEY EYE CTR,DEPT OPHTHALMOL,LA JOLLA,CA 92093. UNIV SO CALIF,DOHENY EYE INST,LOS ANGELES,CA 90089. UNIV PITTSBURGH,MED CTR,DEPT NEUROPATHOL,PITTSBURGH,PA 15260. KATHOLIEKE UNIV LEUVEN,REGA INST MED RES,B-3001 LOUVAIN,BELGIUM. USN HOSP,SAN DIEGO,CA 92134. FU NEI NIH HHS [EY07366] NR 49 TC 21 Z9 22 U1 0 U2 1 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0014-4835 J9 EXP EYE RES JI Exp. Eye Res. PD MAY PY 1997 VL 64 IS 5 BP 795 EP 806 DI 10.1006/exer.1996.0273 PG 12 WC Ophthalmology SC Ophthalmology GA XD248 UT WOS:A1997XD24800017 PM 9245910 ER PT J AU Nicolas, KR Lindenmuth, WT Weller, CS Anthony, DG AF Nicolas, KR Lindenmuth, WT Weller, CS Anthony, DG TI Radar imaging of water surface flow fields SO EXPERIMENTS IN FLUIDS LA English DT Article ID ROUND JET AB We describe the capabilities of coherent high resolution radar to observe remotely the effects of an upwelling subsurface flow on the water surface. This observation is possible because the radar radiation backscatters very strongly from surface features with dimensions similar to its wavelength, in this case X-band at 0.03 m. This technique provides imaging capability with relatively high spatial resolution (similar to 0.3 m) and fast time sampling (similar to 0.006 s) over a large surface area. The processed data reveal both the line-of-sight velocity spectrum of moving water surface features, and their water surface radar backscatter cross-section. We believe that the surface features are generated by subsurface vortices oriented normal to the surface. The vortices are advected with the bulk flow of the jet. Our radar observations of the down-stream flow from a submerged waterjet that is directed parallel to the surface are consistent with those previously measured by laser velocimetry. RP Nicolas, KR (reprint author), USN,CTR SURFACE WARFARE,CARDEROCK DIV,DAVID TAYLOR MODEL BASIN,BETHESDA,MD 20817, USA. NR 11 TC 5 Z9 5 U1 0 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0723-4864 J9 EXP FLUIDS JI Exp. Fluids PD MAY PY 1997 VL 23 IS 1 BP 14 EP 19 DI 10.1007/s003480050081 PG 6 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA XD624 UT WOS:A1997XD62400002 ER PT J AU Butler, JT Sasao, T AF Butler, JT Sasao, T TI On the proportion of digits in redundant numeration systems SO FIBONACCI QUARTERLY LA English DT Article ID REPRESENTATION; NUMBERS C1 USN,POSTGRAD SCH,DEPT ELECT & COMP ENGN,MONTEREY,CA 93943. KYUSHU INST TECHNOL,DEPT COMP SCI & ELECT,IIZUKA,FUKUOKA 820,JAPAN. NR 14 TC 0 Z9 0 U1 0 U2 0 PU FIBONACCI ASSOC PI SANTA CLARA PA UNIV SANTA CLARA, SANTA CLARA, CA 95053 SN 0015-0517 J9 FIBONACCI QUART JI Fibonacci Q. PD MAY PY 1997 VL 35 IS 2 BP 172 EP 180 PG 9 WC Mathematics SC Mathematics GA WY287 UT WOS:A1997WY28700012 ER PT J AU Gershenson, M AF Gershenson, M TI Simple interpretation of time-domain electromagnetic sounding using similarities between wave and diffusion propagation SO GEOPHYSICS LA English DT Article ID LAPLACE TRANSFORM AB By using similarities between EM sounding in dielectric and conductive media, it is shown that one can transform between solutions in one type of propagation to the other. The method is based on the similarities of the Laplace transform between diffusive and nondiffusive cases. In the diffusive case, the equation involves the Laplace variable s in the first power, while for the nondiffusive cases, similar equations occur with s(2). Three alternative implementations are developed, and their use is demonstrated. The first implementation is based on substituting s(2) for the Laplace transform variable s using forward and inverse numerical Laplace transforms. The second implementation is based on expanding the diffusive time response on an exponential time base and replacing it with its image function in the wave case, namely, a sinusoidal function. The third implementation is based on direct transformation in the time domain using exponential time interval sampling. The performance of the techniques on synthetic data is demonstrated. Besides the advantage of simple implementation of these techniques, other advantages and limitations of the method and each of the implementations are discussed. A case history is presented. The application of common techniques used in the processing of seismic and radar for processing and EM sounding in conductive media is discussed. The use of the Poynting vector as a means of determining distance and direction is demonstrated. RP Gershenson, M (reprint author), USN,CTR SURFACE WARFARE,COASTAL SYST STN,DAHLGREN DIV,CODE 22R,PANAMA CITY,FL 32407, USA. NR 16 TC 11 Z9 12 U1 0 U2 2 PU SOC EXPLORATION GEOPHYSICISTS PI TULSA PA 8801 S YALE ST, TULSA, OK 74137 SN 0016-8033 J9 GEOPHYSICS JI Geophysics PD MAY-JUN PY 1997 VL 62 IS 3 BP 763 EP 774 DI 10.1190/1.1444186 PG 12 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA XB685 UT WOS:A1997XB68500007 ER PT J AU Fliflet, AW Manheimer, WM Sprangle, PA AF Fliflet, AW Manheimer, WM Sprangle, PA TI Low-voltage infrared free-electron lasers based on gyrotron-powered RF wigglers SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article DE corrugated waveguides; free-electron lasers; millimeter-wave generation; quasi-optical gyrotron ID QUASI-OPTICAL GYROTRON; ELECTROMAGNETIC WIGGLERS; WAVE; MODE; MASER; CW AB Designs are presented for infrared free-electron lasers (FEL's) with gyrotron-powered electromagnetic wigglers and relatively low voltage electron beams, The use of an electromagnetic wiggler formed by a quasi-optical gyrotron, where the radiation is coupled into a corrugated waveguide, has the potential for substantial increases of FEL gain compared to an open mirror system, Designs for proof-of-principle low-voltage infrared FEL experiments based on both radio-frequency (RF) linear accelerator and electrostatic accelerator technology are presented together with point designs for portable systems covering the infrared windows in the atmosphere. RP USN, RES LAB, DIV PLASMA PHYS, WASHINGTON, DC 20375 USA. NR 36 TC 1 Z9 1 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9197 EI 1558-1713 J9 IEEE J QUANTUM ELECT JI IEEE J. Quantum Electron. PD MAY PY 1997 VL 33 IS 5 BP 669 EP 676 DI 10.1109/3.572140 PG 8 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA WV969 UT WOS:A1997WV96900005 ER PT J AU Pieper, RJ AF Pieper, RJ TI The Eikonal ray equations in optical fibers SO IEEE TRANSACTIONS ON EDUCATION LA English DT Article DE fiber optics; geometric optics; ray trajectories AB The traditional methods for the characterization of ray trajectories in nonhomogeneous media are based on the Eikonal equation valid in the region of geometrical optics. To apply Eikonal theory to fiber optics requires a fairly extensive use of vector calculus and geometry. Alternatively, through a simple correspondence rule, and a few intuitive guidelines for relating ray's to waves, an equivalent set of trajectory equations can be obtained. This approach results in the Eikonal equations for the space evolution of optical fiber rays which are expressed in terms of the mode analysis invariants, azimuthal mode number, and optical waveguide propagation phase constant. RP Pieper, RJ (reprint author), USN,POSTGRAD SCH,DEPT ELECT & COMP ENGN,MONTEREY,CA 93943, USA. NR 13 TC 3 Z9 3 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9359 J9 IEEE T EDUC JI IEEE Trans. Educ. PD MAY PY 1997 VL 40 IS 2 BP 139 EP 143 DI 10.1109/13.572328 PG 5 WC Education, Scientific Disciplines; Engineering, Electrical & Electronic SC Education & Educational Research; Engineering GA WX310 UT WOS:A1997WX31000004 ER PT J AU Gill, GS AF Gill, GS TI Ultra-wideband radar using Fourier synthesized waveforms SO IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY LA English DT Article AB Traditional methods of ultra-wideband (UWB) radar signal generation suffer from several disadvantages such as low antenna radiation efficiency and lack of accurate control of signal parameters like pulse shape, pulse repetition interval (PRI), and its spectrum. UWB signals can be generated by expanding the desired radar waveform in Fourier series and then synthesizing the waveform by generating the individual terms in the expansion from harmonically related oscillators, Signals thus produced overcome the disadvantages of traditional methods of UWB signal generation. In this paper, Fourier series based method for generation of complex amplitude coded waveforms is developed which can be used to generate time domain equivalent of Barker and other codes for application in radar and communication areas. In radar applications, these coded waveforms, with accurate and stable waveform parameters, shall allow pulse compression and coherent integration, The additional processing gain provided by these operations reduces the need for high peak power in radar transmitters which is one of the bottlenecks in the implementation of operational UWB radars. This paper also describes a UWB radar concept which incorporates Fourier synthesized waveforms. Related digital signal processing issues are also discussed. RP Gill, GS (reprint author), USN,POSTGRAD SCH,DEPT ELECT & COMP ENGN,MONTEREY,CA 93943, USA. NR 7 TC 10 Z9 11 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9375 J9 IEEE T ELECTROMAGN C JI IEEE Trans. Electromagn. Compat. PD MAY PY 1997 VL 39 IS 2 BP 124 EP 131 DI 10.1109/15.584934 PG 8 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA WZ162 UT WOS:A1997WZ16200006 ER PT J AU Kruppa, W Boos, JB AF Kruppa, W Boos, JB TI Low-frequency transconductance dispersion in InAlAs/InGaAs/InP HEMT's with single- and double-recessed gate structures SO IEEE TRANSACTIONS ON ELECTRON DEVICES LA English DT Article ID DEEP AB The effects of trapping mechanisms on the transconductance of single- and double-recessed InAlAs/InGaAs/InP HEMT's are examined, Measurements at room temperature indicate transconductance dispersion occurring primarily between 100 Hz and 1 MHz. A detailed examination of the dispersion yields two mechanisms with different activation energies which were determined by measuring the transition frequencies as functions of temperature, One mechanism, causing negative dispersion, has an activation energy of 0.17 eV and was found only in the double-recessed structure, The other mechanism, causing positive dispersion and common to both structures, has a dominant transition with an activation energy of 0.51 eV at low fields, The first mechanism appears to be associated with surface states, while the second is caused by electron traps in the InAlAs or its interface with the InGaAs channel. Transient response measurements were also used to examine the location of the traps and to study the field dependence of the characteristic times. RP Kruppa, W (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 19 TC 19 Z9 19 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9383 J9 IEEE T ELECTRON DEV JI IEEE Trans. Electron Devices PD MAY PY 1997 VL 44 IS 5 BP 687 EP 692 DI 10.1109/16.568027 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA WV648 UT WOS:A1997WV64800002 ER PT J AU Priebe, CE Marchette, DJ Rogers, GW AF Priebe, CE Marchette, DJ Rogers, GW TI Segmentation of random fields via borrowed strength density estimation SO IEEE TRANSACTIONS ON PATTERN ANALYSIS AND MACHINE INTELLIGENCE LA English DT Article DE mixture model; profile likelihood; image analysis; digital mammography ID CLASSIFICATION; ALGORITHM; TISSUE AB In many applications, spatial observations must be segmented into homogeneous regions and the number, positions, and shapes of the regions are unknown a priori. information about the underlying probability distributions for observations in the various regions can be useful in such a procedure, but these distributions are often unknown. Furthermore, while there may be a large number of observations overall, the anticipated regions of interest maybe small with few observations from the individual regions. This paper presents a technique designed to address these difficulties. A simple segmentation procedure can be obtained as a clustering of the disjoint subregions obtained through an initial low-level partitioning procedure. Clustering of these subregions based upon a similarity matrix derived from estimates of their marginal probability density functions yields the resultant segmentation. It is shown that this segmentation is improved through the use of a ''borrowed strength'' density estimation procedure wherein potential similarities between the density functions for the subregions are exploited. The borrowed strength technique is described and the performance of segmentation based on these estimates is investigated through an example from statistical image analysis. C1 USN, CTR SURFACE WARFARE, DAHLGREN, VA 22448 USA. RP JOHNS HOPKINS UNIV, DEPT MATH SCI, BALTIMORE, MD 21218 USA. RI Priebe, Carey E./A-3305-2010 NR 19 TC 8 Z9 8 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 0162-8828 EI 1939-3539 J9 IEEE T PATTERN ANAL JI IEEE Trans. Pattern Anal. Mach. Intell. PD MAY PY 1997 VL 19 IS 5 BP 494 EP 499 DI 10.1109/34.589209 PG 6 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA XB163 UT WOS:A1997XB16300008 ER PT J AU Ashton, RW Ciezki, JG AF Ashton, RW Ciezki, JG TI A novel power systems program at the naval postgraduate school SO IEEE TRANSACTIONS ON POWER SYSTEMS LA English DT Article; Proceedings Paper CT 1996 IEEE/PES Summer Meeting CY JUL 28-AUG 01, 1996 CL DENVER, CO SP IEEE Power Engn Soc, PES DE power engineering education; modeling; simulation and power laboratory ID UNIVERSITY; FUTURE AB The Power Systems program at the Naval Postgraduate School is a unique academic endeavor which seeks to both educate Navy officers in relevant advanced technologies and to complement the research efforts on-going at the government laboratories. The move toward incorporating more-electric technology into naval combatant shipboard power systems and the requisite analysis of such finite-inertia, stiffly-connected systems have driven the development of a program that intermixes power electronics, electric machines, and microprocessors. Through work emphasizing analysis, hands-on hardware investigation and simulation, the students are exposed to the diverse issues encountered in power system research. The students are also presented unique opportunities to interact on-site with various government laboratory sponsors to further draw the connection between theory and hardware implementation. RP Ashton, RW (reprint author), USN,POSTGRAD SCH,DEPT ELECT & COMP ENGN,MONTEREY,CA 93943, USA. NR 24 TC 1 Z9 1 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0885-8950 J9 IEEE T POWER SYST JI IEEE Trans. Power Syst. PD MAY PY 1997 VL 12 IS 2 BP 515 EP 520 DI 10.1109/59.589589 PG 6 WC Engineering, Electrical & Electronic SC Engineering GA WW130 UT WOS:A1997WW13000001 ER PT J AU Pace, PE Leino, RE Styer, D AF Pace, PE Leino, RE Styer, D TI Use of the symmetrical number system in resolving single-frequency undersampling aliases SO IEEE TRANSACTIONS ON SIGNAL PROCESSING LA English DT Article DE analog-to-digital conversion; residues; symmetrical folding AB The relationship between the discrete Fourier transform (DFT) and the symmetrical number system (SNS) is examined as a means of resolving single-frequency undersampling aliases (f > f(s)/2). It is shown that the DFT naturally encodes the frequency information of a signal in a format that is in the same farm as the SNS, Consequently, aliases that result from undersampling a signal can be resolved exactly using r greater than or equal to 2 channels, To demonstrate the concept, two- and three-channel examples are presented, Using the SNS properties of the DFT, the undersampling aliases can be easily resolved to a much greater extent than previously possible. C1 UNIV CINCINNATI,DEPT MATH SCI,CINCINNATI,OH 45221. RP Pace, PE (reprint author), USN,POSTGRAD SCH,DEPT ELECT & COMP ENGN,MONTEREY,CA 93943, USA. NR 7 TC 23 Z9 24 U1 1 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1053-587X J9 IEEE T SIGNAL PROCES JI IEEE Trans. Signal Process. PD MAY PY 1997 VL 45 IS 5 BP 1153 EP 1160 DI 10.1109/78.575690 PG 8 WC Engineering, Electrical & Electronic SC Engineering GA WW842 UT WOS:A1997WW84200005 ER PT J AU Gue, KR Nemhauser, GL Padron, M AF Gue, KR Nemhauser, GL Padron, M TI Production scheduling in almost continuous time SO IIE TRANSACTIONS LA English DT Article ID BOUND ALGORITHM; SYSTEMS; BRANCH; SHOP AB We present a large-scale production scheduling problem where each order is unique and the processing time for an operation can be close to the size of a time period. Because modeling the problem as a multiprocessor flowshop results in a computationally intractable formulation, we cast the problem in production planning terms and extract a production schedule from the solution. To solve our model, we introduce the notion of 'almost continuous time' and show how to obtain good solutions to large problems efficiently. C1 GEORGIA INST TECHNOL, SCH IND & SYST ENGN, ATLANTA, GA 30332 USA. LUCENT TECHNOL, NORCROSS, GA 30071 USA. RP USN, POSTGRAD SCH, DEPT SYST MANAGEMENT, MONTEREY, CA 93943 USA. NR 14 TC 5 Z9 5 U1 0 U2 1 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 530 WALNUT STREET, STE 850, PHILADELPHIA, PA 19106 USA SN 0740-817X EI 1545-8830 J9 IIE TRANS JI IIE Trans. PD MAY PY 1997 VL 29 IS 5 BP 391 EP 398 DI 10.1080/07408179708966344 PG 8 WC Engineering, Industrial; Operations Research & Management Science SC Engineering; Operations Research & Management Science GA XB164 UT WOS:A1997XB16400005 ER PT J AU Guo, WX Burger, AM Fischer, RT Sieckmann, DG Longo, DL Kenny, JJ AF Guo, WX Burger, AM Fischer, RT Sieckmann, DG Longo, DL Kenny, JJ TI Sequence changes at the V-D junction of the V(H)1 heavy chain of anti-phosphocholine antibodies alter binding to and protection against Streptococcus pneumoniae SO INTERNATIONAL IMMUNOLOGY LA English DT Article DE junctional diversity; pneumococcal vaccine; T15 idiotype ID IMMUNE-DEFICIENT MICE; III PNEUMOCOCCAL POLYSACCHARIDE; VARIABLE REGION GENE; PHOSPHORYLCHOLINE ANTIBODIES; MONOCLONAL-ANTIBODIES; B-CELLS; SOMATIC MUTATION; MOUSE; IDIOTYPE; IGM AB X-linked immune deficient (Xid) mice fail to produce anti-phosphocholine (PC) antibodies even after immunization with Streptococcus pneumoniae. Consequently, Xid mice are extremely susceptible to infection with S. pneumoniae. PC-specific a cells appear to undergo clonal deletion in Xid mice; however, a new thymus-dependent form of PC, 6-(O-phosphocholine)hydroxyhexanoate (EPC), can rescue PC-specific B cells from the bone marrow presumably by providing T cell help before clonal deletion. Analysis of PC-specific IgG hybridomas from Xid mice revealed utilization of several V-D junctional variants of the V(H)1 gene segment rearranged to different D and J(H) gene segments. The majority of Xid anti-PC antibodies exhibit an Asp --> Gly95H replacement at the V-D junction. These Gly95H V(H)1 variants associate with kappa 1C L chains to produce anti-PC antibodies that: (i) have low relative affinity for PC, (ii) are heteroclitic for nitrophenylphosphocholine and (iii) fail to bind to or provide protection against S. pneumoniae. Single prototypic V-D variants of the T15 idiotype (Asp95H), M603 idiotype (Asn95H) and M167 idiotype (Asp95H-Ala96H) were also induced in Xid mice. The M603-like and M167-like antibodies bound to and protected against S. pneumoniae even though they exhibited K(a)s for PC which were lower than T15 idiotype(+) antibodies. These data demonstrate that small changes in the V-D junctional sequence of the T15 (V(H)1) heavy chain alter L chain usage and the structure of the PC binding site so that the PC expressed on S. pneumoniae is no longer recognized. C1 NIA,GERONTOL RES CTR,NIH,BALTIMORE,MD 21224. USN,MED RES INST,BETHESDA,MD 20889. UNIV BRADFORD,CLIN ONCOL UNIT,BRADFORD BD7 1DP,W YORKSHIRE,ENGLAND. NCI,FREDERICK CANC RES & DEV CTR,LAB BIOCHEM PHYSIOL,FREDERICK,MD 21702. NR 54 TC 19 Z9 19 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD, ENGLAND OX2 6DP SN 0953-8178 J9 INT IMMUNOL JI Int. Immunol. PD MAY PY 1997 VL 9 IS 5 BP 665 EP 677 DI 10.1093/intimm/9.5.665 PG 13 WC Immunology SC Immunology GA XD240 UT WOS:A1997XD24000004 PM 9184912 ER PT J AU Harter, JSS Campbell, ML McClean, RE AF Harter, JSS Campbell, ML McClean, RE TI Depletion kinetics of low-lying states of tungsten in the presence of NO, N2O, and SO2 SO INTERNATIONAL JOURNAL OF CHEMICAL KINETICS LA English DT Article ID TRANSITION-METAL ATOMS; CHEMICAL VAPOR-DEPOSITION; GAS-PHASE; OXIDATION REACTIONS; TEMPERATURE; O-2; REACTIVITY; TI(A(3)F); TI(A3F); 300-K AB The gas-phase reactivities of W(a(5)D(1), a(7)S(3)) with N2O, SO2, and NO in the temperature range of 295-573 K are reported. Tungsten atoms were produced by the photodissociation of W(CO)(6). The tungsten atoms were detected by a laser-induced fluorescence technique. The removal rate constants for the 6s(2)5d(4) a(5)D(1) states were found to be J dependent for all of the reactants. Removal rate constants for the 6s(1)5d(5) a(7)S(3) state were found to be ast compared to the a(5)D(1) states and often approached the gas kinetic rate constant. The reaction rates for all the states were found to be pressure independent with respect to the total pressure. Results are discussed in terms of the different electronic configurations of the states of tungsten. (C) 1997 John Wiley & Sons. Inc. C1 USN ACAD,DEPT CHEM,ANNAPOLIS,MD 21402. UNIV MARYLAND,DEPT CHEM,COLLEGE PK,MD 20742. NR 32 TC 19 Z9 19 U1 0 U2 2 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0538-8066 J9 INT J CHEM KINET JI Int. J. Chem. Kinet. PD MAY PY 1997 VL 29 IS 5 BP 367 EP 375 DI 10.1002/(SICI)1097-4601(1997)29:5<367::AID-KIN7>3.0.CO;2-S PG 9 WC Chemistry, Physical SC Chemistry GA WU985 UT WOS:A1997WU98500007 ER PT J AU Gillum, MJ Lewis, MJ AF Gillum, MJ Lewis, MJ TI Experimental results on a Mach 14 waverider with blunt leading edges SO JOURNAL OF AIRCRAFT LA English DT Article; Proceedings Paper CT AIAA 34th Aerospace Sciences Meeting and Exhibit CY JAN 15-19, 1996 CL RENO, NV SP Amer Inst Aeronaut & Astronaut AB The results of wind-tunnel tests of a Mach 14 waverider were analyzed to assess its overall performance, The waverider was optimized using a figure of merit that included viscosity, volume, and lift to-drag considerations, The final design included a 0.25-in. leading-edge radius, The general performance of the tested waverider was analyzed and compared to the theoretical design from which it was derived, The theoretical design was generated from a conical flowfield, where the vehicle's infinitely sharp leading edges were everywhere-attached to the conical shock. Since the tested waverider featured blunt leading edges, it was important to assess the performance losses associated with now spillage; these losses were found to be relatively small, However, the increased drag due to the blunt leading edges contributed greatly to reducing the aerodynamic performance of the tested waverider. Also, it was found that the aerodynamic coefficient data were insensitive to changes in Mach number and Reynolds number, indicating excellent off-design performance for the ranges of values tested. C1 UNIV MARYLAND,DEPT AEROSP ENGN,COLLEGE PK,MD 20742. RP Gillum, MJ (reprint author), USN,CTR SURFACE WARFARE,DAHLGREN DIV,WHITE OAK DETACHMENT,REENTRY SYST BRANCH,SILVER SPRING,MD 20903, USA. NR 21 TC 27 Z9 31 U1 0 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD MAY-JUN PY 1997 VL 34 IS 3 BP 296 EP 303 DI 10.2514/2.2198 PG 8 WC Engineering, Aerospace SC Engineering GA XB843 UT WOS:A1997XB84300005 ER PT J AU Yamaguchi, M Takamoto, T Taylor, SJ Walters, RJ Summers, GP Flood, DJ Ohmori, M AF Yamaguchi, M Takamoto, T Taylor, SJ Walters, RJ Summers, GP Flood, DJ Ohmori, M TI Correlations for damage in diffused-junction InP solar cells induced by electron and proton irradiation SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID SINGLE-CRYSTALS AB The damage to diffused-junction n(+)-p InP solar cells induced by electron and proton irradiations over a wide range of energy from 0.5 to 3 MeV and 0.015 to 20 MeV, respectively, has been examined. The experimental electron and proton damage coefficients have been analyzed in terms of displacement damage dose, which is the product of the particle fluence and the calculated nonionizing energy loss [G. P. Summers, E. A. Burke, R. Shapiro, S. R. Messenger, and R. J. Waiters, IEEE Trans. Nucl. Sci. 40, 1300 (1993).] Degradation of InP cells due to irradiation with electrons and protons with energies of more than 0.5 MeV show a single curve as a function of displacement damage dose. Based on the deep-level transient spectroscopy analysis, damage equivalence between electron and proton irradiation is discussed. InP solar cells are confirmed to be substantially more radiation resistant than Si and GaAs-on-Ge cells. (C) 1997 American Institute of Physics. C1 USN,RES LAB,WASHINGTON,DC 20375. NASA,LEWIS RES CTR,CLEVELAND,OH 44135. JAPAN ENERGY CO,CENT RES LAB,TODA,SAITAMA 335,JAPAN. RP Yamaguchi, M (reprint author), TOYOTA TECHNOL INST,TEMPAKU KU,2-12 HISAKATA,NAGOYA,AICHI 468,JAPAN. NR 9 TC 15 Z9 16 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 1997 VL 81 IS 9 BP 6013 EP 6018 DI 10.1063/1.364449 PG 6 WC Physics, Applied SC Physics GA WW729 UT WOS:A1997WW72900020 ER PT J AU Ngai, KL Floudas, G Rizos, AK AF Ngai, KL Floudas, G Rizos, AK TI Distribution of reorientational times of optically anisotropic molecular liquids from depolarized light-scattering studies SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ORTHO-TERPHENYL; NEUTRON-SCATTERING; GLASS-TRANSITION; SUPERCOOLED LIQUID; ALPHA-RELAXATION; DIELECTRIC-RELAXATION; AROCLOR SOLUTIONS; TOLUENE SOLUTIONS; SOLVENT MOBILITY; BETA-RELAXATION AB Several optically anisotropic glass-forming liquids have been studied by depolarized Rayleigh scattering in the region of the alpha relaxation. These liquids have a fourfold difference in T-g's, a fivefold difference in optical anisotropies gamma(eff)(2)'s, and a sevenfold difference in hydrodynamic volumes V-h's. The analysis of the distribution of relaxation times has been carried out using both the raw intensity data and the corresponding susceptibility representation of the same data. These results are combined with light scattering and dielectric data obtained at lower frequencies. Notwithstanding the great differences in T-g's, gamma(eff)(2)'s, and V-h's, the liquids show that their distributions of relaxation times from light scattering narrow with increasing temperature. In some, though not all, liquids, an unbiased analysis of the data indicates that the distribution tends to narrow towards a single exponential time (Debye) spectrum consistent with the extrapolation of the dielectric relaxation measurements from lower temperatures. The light-scattering results, consistent with dielectric and shear viscosity data, are discussed in their relation to current theoretical interpretations. (C) 1997 American Institute of Physics. C1 FDN RES & TECHNOL HELLAS,INST ELECT STRUCT & LASER,IRAKLION 71110,CRETE,GREECE. UNIV CRETE,DEPT CHEM,IRAKLION 71409,CRETE,GREECE. RP Ngai, KL (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. RI Rizos, Apostolos/F-6807-2011; Floudas, George/M-7985-2015 NR 65 TC 15 Z9 15 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 1 PY 1997 VL 106 IS 17 BP 6957 EP 6963 DI 10.1063/1.473720 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA WV763 UT WOS:A1997WV76300018 ER PT J AU Blair, PJ Boise, LH Perfetto, SP Levine, BL McCrary, G Wagner, KF StLouis, DC Thompson, CB Siegel, JN June, CH AF Blair, PJ Boise, LH Perfetto, SP Levine, BL McCrary, G Wagner, KF StLouis, DC Thompson, CB Siegel, JN June, CH TI Impaired induction of the apoptosis-protective protein Bcl-x(L) in activated PBMC from asymptomatic HIV-infected individuals SO JOURNAL OF CLINICAL IMMUNOLOGY LA English DT Article DE HIV/AIDS; costimulatory molecules; apoptosis; cell survival genes ID PROGRAMMED CELL-DEATH; BCL-X; PERIPHERAL-BLOOD; T-LYMPHOCYTES; FAS ANTIGEN; LYMPH-NODES; EXPRESSION; MICE; BAX; TRANSLATION AB Progression to AIDS in asymptomatic HIV-infected individuals is characterized by a gradual but progressive loss of CD4(+) T cells. While the mechanisms underlying this decline are currently unknown, recent evidence suggests that these cells are abnormally sensitive to apoptosis in response to activation signals. Recent work has implicated downregulation of Bcl-2 with the increased spontaneous apoptosis in lymphocytes from HIV-infected patients. We have evaluated the roles of the apoptosis-protective proteins Bcl-2 and Bcl-x in stimulated PBMC from asymptomatic HIV-infected and HIV-uninfected individuals. We found that Bcl-2 was constitutively expressed in PBMC from both HIV-infected and uninfected samples. However, Bcl-x induction was delayed and responses were decreased in stimulated HN-infected samples. Additionally, single-cell intracellular staining of Bcl-x revealed a significant inverse correlation between PWM-induced Bcl-x expression and apoptosis (r = -0.695, P = 0.005). This was confirmed at the single-cell level in direct experiments when stimulated cells were sorted based on Bcl-x induction and then measured for apoptosis. Furthermore, low Bcl-x expression was not due to reduced lymphocyte activation following PWM stimulation. Our data indicate that the induction of Bcl-x is markedly impaired in asymptomatic HIV-infected patients and that stimuli which induce inadequate expression of Bcl-x are associated with increased levels of apoptosis in these cells. C1 UNIV CHICAGO,GWEN KNAPP CTR LUPUS & IMMUNOL RES,CHICAGO,IL 60637. HENRY M JACKSON FDN ADVANCEMENT MIL MED,ROCKVILLE,MD 20850. RP Blair, PJ (reprint author), USN,MED RES INST,IMMUNE CELL BIOL PROGRAM 061,BETHESDA,MD 20889, USA. RI Levine, Bruce/D-1688-2009 NR 61 TC 15 Z9 16 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0271-9142 J9 J CLIN IMMUNOL JI J. Clin. Immunol. PD MAY PY 1997 VL 17 IS 3 BP 234 EP 246 DI 10.1023/A:1027310612323 PG 13 WC Immunology SC Immunology GA XA037 UT WOS:A1997XA03700006 PM 9168404 ER PT J AU Neta, B Giraldo, FX Navon, IM AF Neta, B Giraldo, FX Navon, IM TI Analysis of the Turkel-Zwas scheme for the two-dimensional shallow water equations in spherical coordinates SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article ID MODEL AB A linear analysis of the shallow water equations in spherical coordinates for the Turkel-Zwas (T-Z) explicit large time-step scheme is presented. This paper complements the results of Schoenstadt, Neta and Navon, and others in 1-D, and of Neta and DeVito in 2-D, but applied to the spherical coordinate case of the T-Z scheme. This coordinate system is more realistic in meteorology and more complicated to analyze, since the coefficients are no longer constant. The analysis suggests that the T-Z scheme must be staggered in a certain way in order to get eigenvalues and eigenfunctions approaching those of the continuous case. The importance of such an analysis is the fact that it is also valid for nonconstant coefficients and thereby applicable to any numerical scheme. Numerical experiments comparing the original (unstaggered) and staggered versions of the T-Z scheme are presented. These experiments corroborate the analysis by showing the improvements in accuracy gained by staggering the Turkel-Zwas scheme. (C) 1997 Academic Press. C1 FLORIDA STATE UNIV,DEPT MATH,TALLAHASSEE,FL 32306. FLORIDA STATE UNIV,SUPERCOMP COMPUTAT RES INST,TALLAHASSEE,FL 32306. RP Neta, B (reprint author), USN,POSTGRAD SCH,DEPT MATH,MONTEREY,CA 93943, USA. RI Navon, Ionel/A-5173-2008; Neta, Beny/B-1737-2009 OI Navon, Ionel/0000-0001-7830-7094; NR 14 TC 11 Z9 11 U1 0 U2 4 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD MAY 1 PY 1997 VL 133 IS 1 BP 102 EP 112 DI 10.1006/jcph.1997.5657 PG 11 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA WX892 UT WOS:A1997WX89200009 ER PT J AU Thibado, PM Bennett, BR Shanabrook, BV Whitman, LJ AF Thibado, PM Bennett, BR Shanabrook, BV Whitman, LJ TI A RHEED and STM study of Sb-rich AlSb and GaSb (001) surface reconstructions SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 9th International Conference on Molecular Beam Epitaxy (MBE-IX) CY AUG 05-09, 1996 CL PEPPERDINE UNIV, MALIBU, CA HO PEPPERDINE UNIV ID SCANNING-TUNNELING-MICROSCOPY; ENERGY ELECTRON-DIFFRACTION; MOLECULAR-BEAM EPITAXY; GALLIUM ANTIMONIDE; GROWTH; SEMICONDUCTORS; PHOTOEMISSION AB The structure of AlSb and GaSb (0 0 1) surfaces prepared by molecular beam epitaxy has been studied with in-situ reflection high-energy electron diffraction and scanning tunneling microscopy. Under fixed Sb-4 flux, two AlSb reconstructions are observed with increasing temperature (and decreasing surface Sb:Al coverage): c(4 x 4), as observed for InSb, GaAs, AlAs, and InAs, and (1 x 3). In contrast, GaSb reconstructions observed with increasing temperature are: (2 x 5), (1 x 5), c(2 x 6), and (1 x 3). Whereas the (1 x 5), c(2 x 6), and (1 x 3) surfaces are composed primarily of Sb dimer rows on top of an Sb-terminated surface, the (2 x 5) surface is composed of Sb dimer rows on top of two layers of Sb (i.e. the surface is terminated by three Sb layers). We speculate that GaSb is unique in forming the (n x 5) reconstructions due to its excellent lattice match with trigonally bonded elemental Sb. C1 USN,RES LAB,WASHINGTON,DC 20375. RI Bennett, Brian/A-8850-2008; Whitman, Lloyd/G-9320-2011 OI Bennett, Brian/0000-0002-2437-4213; Whitman, Lloyd/0000-0002-3117-1174 NR 23 TC 22 Z9 22 U1 3 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAY PY 1997 VL 175 BP 317 EP 322 DI 10.1016/S0022-0248(96)00982-7 PN 1 PG 6 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA XL451 UT WOS:A1997XL45100056 ER PT J AU Bennett, BR Shanabrook, BV Thibado, PM Whitman, LJ Magno, R AF Bennett, BR Shanabrook, BV Thibado, PM Whitman, LJ Magno, R TI Stranski-Krastanov growth of InSb, GaSb, and AlSb on GaAs: structure of the wetting layers SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 9th International Conference on Molecular Beam Epitaxy (MBE-IX) CY AUG 05-09, 1996 CL PEPPERDINE UNIV, MALIBU, CA HO PEPPERDINE UNIV ID SCANNING-TUNNELING-MICROSCOPY; BEAM EPITAXIAL-GROWTH; SELF-ASSEMBLED INSB; QUANTUM DOTS; HETEROEPITAXY; SURFACE; PHOTOLUMINESCENCE; NUCLEATION; EVOLUTION; GAAS(001) AB Thin layers of InSb, GaSb and AlSb were grown on GcAs(001) by molecular beam epitaxy and characterized in situ with scanning tunneling microscopy. AII three materials exhibit a Stranski-Krastanov growth mode. Distinct wetting layers and self-assembled quantum dots are present after deposition of one to four monolayers of (In,Ga,Al)Sb. The wetting layers consist of anisotropic, ribbon-like structures oriented along the [101] direction. with characteristic separations of 40-50 Angstrom. The initial GaAs surface reconstruction affects both the wetting layer structure and the quantum dot density. RP USN, RES LAB, WASHINGTON, DC 20375 USA. RI Bennett, Brian/A-8850-2008; Whitman, Lloyd/G-9320-2011 OI Bennett, Brian/0000-0002-2437-4213; Whitman, Lloyd/0000-0002-3117-1174 NR 25 TC 30 Z9 30 U1 0 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 EI 1873-5002 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAY PY 1997 VL 175 BP 888 EP 893 DI 10.1016/S0022-0248(96)00917-7 PN 2 PG 6 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA XX179 UT WOS:A1997XX17900036 ER PT J AU Lin, CH Murry, SJ Zhang, D Chang, PC Zhou, YC Pei, SS Malin, JI Felix, CL Meyer, JR Hoffman, CA Pinto, JF AF Lin, CH Murry, SJ Zhang, D Chang, PC Zhou, YC Pei, SS Malin, JI Felix, CL Meyer, JR Hoffman, CA Pinto, JF TI MBE grown mid-infrared type-II quantum-well lasers SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 9th International Conference on Molecular Beam Epitaxy (MBE-IX) CY AUG 05-09, 1996 CL PEPPERDINE UNIV, MALIBU, CA HO PEPPERDINE UNIV DE infrared; semiconductor laser; MBE; quantum well ID MOLECULAR-BEAM EPITAXY; MU-M; ROOM-TEMPERATURE; DIODE-LASERS AB We have employed molecular-beam epitaxy (MBE) for the growth of mid-infrared (MIR) type-II quantum-well laser structures. These lasers consist of strain-balanced InAs/InGaSb/InAs/AlSb type-II quantum wells lattice-matched to the AlSb cladding layers. We have demonstrated optically pumped lasers emitting from 3 to 4.3 mu m under pulsed operation. For the 3.2-mu m lasers, stimulated emission was observed at temperatures up to 350 K. The characteristic temperature To at operation temperatures above ambient was 68 K. Here, we discuss the optimization of the MBE growth of MIR type-II quantum-well lasers, including substrate temperatures, V/III beam-equivalent pressure ratios, and shutter sequencing for better interface control and laser performance. C1 UNIV HOUSTON,CTR SPACE VACUUM EPITAXY,HOUSTON,TX 77204. USN,RES LAB,WASHINGTON,DC 20375. NR 13 TC 30 Z9 30 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAY PY 1997 VL 175 BP 955 EP 959 DI 10.1016/S0022-0248(96)00830-5 PN 2 PG 5 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA XX179 UT WOS:A1997XX17900049 ER PT J AU Lin, CH Chang, PC Murry, SJ Zhang, D Yang, RQ Pei, SS Malin, JI Meyer, JR Felix, CL Lindle, JR Goldberg, L Hoffman, CA Bartoli, EJ AF Lin, CH Chang, PC Murry, SJ Zhang, D Yang, RQ Pei, SS Malin, JI Meyer, JR Felix, CL Lindle, JR Goldberg, L Hoffman, CA Bartoli, EJ TI Nearly room-temperature type-II quantum-well lasers at 3-4 mu m SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article DE laser diodes; mid-infrared; type-II heterostructures; quantum wells ID INASSB/GASB AB We report optically pumped four-constituent InAs/lnGaSb/InAs/AlSb type-II quantum-well lasers emitting at 3.2-4.1 mu m. Lasing was observed up to 350K under pulsed operation, with a characteristic temperature T-0 up to 68K at temperatures above ambient. C1 USN,RES LAB,WASHINGTON,DC 20375. RP Lin, CH (reprint author), UNIV HOUSTON,CTR SPACE VACUUM EPITAXY,HOUSTON,TX 77204, USA. RI Lindle, James/A-9426-2009 NR 13 TC 12 Z9 12 U1 0 U2 0 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD MAY PY 1997 VL 26 IS 5 BP 440 EP 443 DI 10.1007/s11664-997-0116-6 PG 4 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA WY101 UT WOS:A1997WY10100005 ER PT J AU Stevens, MH Siskind, DE Hilsenrath, E Cebula, RP Leitch, JW Russell, JM Gordley, LL AF Stevens, MH Siskind, DE Hilsenrath, E Cebula, RP Leitch, JW Russell, JM Gordley, LL TI Shuttle solar backscatter UV observations of nitric oxide in the upper stratosphere, mesosphere, and thermosphere: Comparisons with the Halogen Occultation Experiment SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ABSORPTION CROSS-SECTIONS; WAVELENGTH REGION; SELF-ABSORPTION; GAMMA-BAND; FLUORESCENCE; LIFETIMES; SPECTRUM; OZONE; MODEL AB The shuttle solar backscatter ultraviolet (SSBUV) spectrometer measured nitric oxide (NO) gamma(1,0) and gamma(0,2) band solar fluorescence at 215 and 247 nm, respectively, over a total of four orbits in April 1993 and eight orbits in March 1994. From nadir observations the apparent NO column abundance down to 1 mbar was inferred as a function of latitude and longitude using modeled gamma band emission rate factors, SSBUV 5 results show a factor of 2 increase in NO from 20 degrees S-20 degrees N to 40 degrees-60 degrees S and a large variation of NO with a strong dependence on geomagnetic latitude near 52 degrees S, Nimbus 7 solar backscatter ultraviolet (SBUV) spectrometer NO gamma band fluorescence observations made between 1979 and 1986 were compared with SSBUV observations, and results from the two experiments are consistent for the latitudes observed by SSBUV. Coincident with some of the SSBUV solar fluorescence observations were absorption observations in the 5.3 mu m band of NO by the Halogen Occultation Experiment (HALOE), A one-dimensional model was used to adjust the HALOE density profiles inferred from sunrise occultations to the local solar time of the SSBUV observations, The emission rate factor model was used to convert these density profiles to nadir intensities for direct comparison with SSBUV observations. Results show that HALOE inferred intensities are generally within 25% of SSBUV observations on the same day. C1 HUGHES STX CORP,GREENBELT,MD 20770. NASA,LANGLEY RES CTR,DIV ATMOSPHER SCI,HAMPTON,VA 23681. NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. RP Stevens, MH (reprint author), USN,RES LAB,EO HULBURT CTR SPACE RES,CODE 7641,WASHINGTON,DC 20375, USA. OI Stevens, Michael/0000-0003-1082-8955 NR 39 TC 4 Z9 4 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAY 1 PY 1997 VL 102 IS A5 BP 9717 EP 9727 DI 10.1029/97JA00326 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA WX560 UT WOS:A1997WX56000021 ER PT J AU Scales, WA Myers, TJ Bernhardt, PA Ganguli, G AF Scales, WA Myers, TJ Bernhardt, PA Ganguli, G TI Attachment rate effects during electron attachment chemical releases SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID EARLY TIME EVOLUTION AB The effects of attachment rate on the evolution of electron depletions produced during ionospheric electron attachment chemical releases are studied by using a numerical simulation model. Varying the attachment rate is observed to have important effects on small-scale processes in the depletion boundary layer as well as the large-scale evolution of the depletion. Increasing the attachment rate is observed to increase the amplitude of electrostatic waves in the depletion boundary. The increase in amplitude of these waves is accompanied by an increase in heating of negative ions produced by the electron attachment. Also, the wavelength of waves in the boundary layer is seen to decrease as the attachment rate increases, since steeper density gradients and more highly sheared electron flows are produced. This result indicates that the attachment rate and the size of the release are important factors in setting the scale size of irregularities during the experiments. C1 USN,RES LAB,DIV PLASMA PHYS,WASHINGTON,DC 20375. RP Scales, WA (reprint author), VIRGINIA POLYTECH INST & STATE UNIV,BRADLEY DEPT ELECT ENGN,BLACKSBURG,VA 24061, USA. NR 12 TC 1 Z9 1 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAY 1 PY 1997 VL 102 IS A5 BP 9767 EP 9771 DI 10.1029/97JA00125 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA WX560 UT WOS:A1997WX56000027 ER PT J AU Ross, IM AF Ross, IM TI Suboptimal singular orbital transfer SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article RP Ross, IM (reprint author), USN,POSTGRAD SCH,DEPT AERONAUT & ASTRONAUT,MAIL CODE AA-RO,MONTEREY,CA 93943, USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD MAY-JUN PY 1997 VL 20 IS 3 BP 605 EP 607 DI 10.2514/2.4083 PG 3 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA WY344 UT WOS:A1997WY34400028 ER PT J AU Gritzo, LA Tieszen, SR Murray, D AF Gritzo, LA Tieszen, SR Murray, D TI Flame structure of large, hydrocarbon-fueled pool fires SO JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT International Mechanical Engineering Congress and Exposition - Winter Annual Meeting of the ASME CY NOV 17-22, 1996 CL ATLANTA, GA SP Amer Soc Mech Engineers C1 USN,AIR WARFARE CTR,WEAPONS DIV,CHINA LAKE,CA. RP Gritzo, LA (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0022-1481 J9 J HEAT TRANS-T ASME JI J. Heat Transf.-Trans. ASME PD MAY PY 1997 VL 119 IS 2 BP 209 EP 209 DI 10.1115/1.2824210 PG 1 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA XB119 UT WOS:A1997XB11900011 ER PT J AU Cheung, K Ohadi, MM Dessiatoun, S Singh, A AF Cheung, K Ohadi, MM Dessiatoun, S Singh, A TI EHD-enhanced boiling coefficients and visualization of R-134a over enhanced tubes SO JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME LA English DT Article DE bolting; finned surfaces; flow visualization ID HEAT-TRANSFER AB In all earlier study by the authors, the applicability of the EHD technique for augmentation of pool boiling heat transfer of R-134a in a tube bundle was demonstrated. This paper reports additional experiments involving optimization of the electrode/heat transfer surface geometry as well as flow visualization studies that provide improved understanding of the EHD-enhanced pool boiling heat transfer in a tube bundle. Utilizing the flow visualization studies, it is demonstrated that combined electroconvection and improved nucleate boiling dynamics give rise to the augmented heat transfer coefficients. C1 UNIV MARYLAND,CTR ENVIRONM ENERGY ENGN,DEPT MECH ENGN,HEAT TRANSFER ENHANCEMENT LAB,COLLEGE PK,MD 20742. COPELAND CORP,ADV DEV CTR,SIDNEY,OH. RP Cheung, K (reprint author), USN,RES LAB,CTR SPACE TECHNOL,WASHINGTON,DC 20375, USA. NR 12 TC 10 Z9 10 U1 0 U2 3 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0022-1481 J9 J HEAT TRANS-T ASME JI J. Heat Transf.-Trans. ASME PD MAY PY 1997 VL 119 IS 2 BP 332 EP 338 DI 10.1115/1.2824228 PG 7 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA XB119 UT WOS:A1997XB11900028 ER PT J AU Gause, WC Chen, SJ Greenwald, RJ Halvorson, MJ Zhou, XD Morris, SC Lee, KP June, CH Finkelman, FD Urban, JF Abe, R AF Gause, WC Chen, SJ Greenwald, RJ Halvorson, MJ Zhou, XD Morris, SC Lee, KP June, CH Finkelman, FD Urban, JF Abe, R TI CD28 dependence of T cell differentiation to IL-4 production varies with the particular type 2 immune response SO JOURNAL OF IMMUNOLOGY LA English DT Article ID ANTIGEN-PRESENTING CELLS; CYTOKINE GENE-EXPRESSION; LYMPHOCYTES-T; CD28-DEFICIENT MICE; ISOTYPE SELECTION; ACTIVATION; HELPER; CTLA-4; NAIVE; INDUCTION AB T cell differentiation to effector cell function is required for the development of a type 2 immune response. The T cell surface molecule, CD28, is widely considered to be the principal costimulatory molecule involved in T cell differentiation to effector function, including IL-4 production, although this has been difficult to directly examine in vivo. We have studied in vivo differentiation to T cell effector function during two type 2 immune responses in CD28 knockout mice: the systemic immune response to goat anti-mouse IgD Ab and the mucosal immune response following oral inoculation with the nematode parasite, Heligmosomoides polygyrus. Our results show that in C57BL/6 CD28 knockout mice elevations in IL-4 gene expression and protein secretion are blocked during the immune response to goat anti-mouse IgD, and associated increases in serum IgG1 and IgE are also inhibited to untreated control levels. In marked contrast, T cell differentiation to IL-4 production is comparable in C57BL/6 CD28 -/- and CD28 +/+ H. polygyrus-inoculated mice, and elevations in both serum IgG1 and IgE levels occur. These results indicate that the specific kind of type 2 immune response determines whether T cell differentiation to IL-4 production is CD28 dependent. C1 UNIFORMED SERV UNIV HLTH SCI,DEPT IMMUNOL & MICROBIOL,BETHESDA,MD 20814. UNIV CINCINNATI,COLL MED,DEPT MED,CINCINNATI,OH 45267. USN,MED RES INST,IMMUNE CELL BIOL PROGRAM,BETHESDA,MD 20889. ARS,IMMUNOL & DIS RESISTANCE LAB,INST LIVESTOCK & POULTRY SCI,USDA,BELTSVILLE,MD 20705. SCI UNIV TOKYO,BIOL SCI RES INST,CHIBA,JAPAN. OI Urban, Joseph/0000-0002-1590-8869 FU NIAID NIH HHS [AI31678] NR 42 TC 59 Z9 59 U1 0 U2 0 PU AMER ASSOC IMMUNOLOGISTS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 SN 0022-1767 J9 J IMMUNOL JI J. Immunol. PD MAY 1 PY 1997 VL 158 IS 9 BP 4082 EP 4087 PG 6 WC Immunology SC Immunology GA WV761 UT WOS:A1997WV76100009 PM 9126966 ER PT J AU Waugh, RE McKenney, JB Bauserman, RG Brooks, DM Valeri, CR Snyder, LM AF Waugh, RE McKenney, JB Bauserman, RG Brooks, DM Valeri, CR Snyder, LM TI Surface area and volume changes during maturation of reticulocytes in the circulation of the baboon SO JOURNAL OF LABORATORY AND CLINICAL MEDICINE LA English DT Article ID MEMBRANE; ERYTHROCYTES; EXTERNALIZATION; RELEASE AB Changes in the surface area and volume of reticulocytes were measured in vivo during late stage maturation. Baboons were treated with erythropoietin to produce mild reticulocytosis. Reticulocyte-rich cohorts of cells were obtained from whole blood by density gradient centrifugation. The cohorts were labeled with biotin, reinfused into the animal, and recovered from whole blood samples by panning on avidin supports. Changes in the surface area, volume, and membrane deformability were measured using micropipettes during the 2 to 6 weeks subsequent to reinfusion. For the entire cohort, the membrane area decreased by 10% to 15% and the cell volume decreased by approximately 8.5%, mostly within 24 hours after reinfusion. Estimates of the cellular dimensions of the reticulocyte subpopulation within this cohort indicated larger reductions in the mean cell area (12% to 30%) and mean cell volume (approximately 15%) of the reticulocytes themselves. Two weeks after reinfusion, the distribution of cell size for the cohort was indistinguishable from that of whole blood. There was evidence of slightly elevated membrane shear rigidity in some reticulocytes before reinfusion, but this slight increase disappeared within 24 hours after reinfusion. These are the first direct measurements of changes in the membrane physical properties of an identifiable cohort of reticulocytes as they mature in vivo. C1 UNIV MASSACHUSETTS,MED CTR,DEPT HOSP LABS,WORCESTER,MA. BOSTON UNIV,SCH MED,USN,BLOOD RES LAB,BOSTON,MA 02215. RP Waugh, RE (reprint author), UNIV ROCHESTER,SCH MED & DENT,DEPT BIOPHYS,601 ELMWOOD AVE,ROCHESTER,NY 14642, USA. FU NHLBI NIH HHS [P01 HL18208] NR 21 TC 31 Z9 31 U1 0 U2 4 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 SN 0022-2143 J9 J LAB CLIN MED JI J. Lab. Clin. Med. PD MAY PY 1997 VL 129 IS 5 BP 527 EP 535 DI 10.1016/S0022-2143(97)90007-X PG 9 WC Medical Laboratory Technology; Medicine, General & Internal; Medicine, Research & Experimental SC Medical Laboratory Technology; General & Internal Medicine; Research & Experimental Medicine GA WW934 UT WOS:A1997WW93400007 PM 9142049 ER PT J AU Dunn, DN Seitzman, LE Singer, IL AF Dunn, DN Seitzman, LE Singer, IL TI The origin of an anomalous, low 2 theta peak in x-ray diffraction spectra of MoS2 films grown by ion beam assisted deposition SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID MOLYBDENUM-DISULFIDE AB The origin of a previously reported anomalous low 2 theta x-ray diffraction peak from MoS2 thin films grown by ion beam assisted deposition was investigated. The anomalous peak, observed in a film grown on Si(100), was removed by ion irradiating the film with 180 keV Ar++ ions to a dose of 1 x 10(15) ions/cm(2). Microstructures of the two films were investigated using x-ray diffraction and cross-section transmission electron microscopy. Diffraction data and bright-field images indicated that the low 28 peak was due to a local interplanar expansion of the crystal structure normal to MoS2 basal planes. This expansion was attributed to molecular defects. RP Dunn, DN (reprint author), USN,RES LAB,CODE 6176,WASHINGTON,DC 20375, USA. NR 6 TC 20 Z9 20 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD MAY PY 1997 VL 12 IS 5 BP 1191 EP 1194 DI 10.1557/JMR.1997.0167 PG 4 WC Materials Science, Multidisciplinary SC Materials Science GA WY198 UT WOS:A1997WY19800007 ER PT J AU Holtz, RL Imam, MA AF Holtz, RL Imam, MA TI Hydrogen storage capacity of submicron magnesium-nickel alloys SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID HYDRIDING PROPERTIES; MG2NI; NI; ABSORPTION AB Magnesium-nickel alloys with nickel concentrations from 0 to 60 at % were prepared by three methods: inert gas condensation of sputtered nanocrystalline powder, cosputtering of amorphous thin films and ball milling. Of the three methods, ball milling yields the best hydrogen storage properties in terms of hydrogen capacity, hydriding/dehydriding rates, and activation requirements. In addition, these characteristics are achieved in magnesium with only very small nickel concentrations, on the order of a few atomic per cent. C1 USN,RES LAB,DIV MAT SCI & TECHNOL,WASHINGTON,DC 20375. RP Holtz, RL (reprint author), GEOCENTERS INC,10903 INDIAN HEAD HIGHWAY,FT WASHINGTON,MD 20744, USA. NR 15 TC 40 Z9 40 U1 0 U2 4 PU CHAPMAN HALL LTD PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8HN SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD MAY 1 PY 1997 VL 32 IS 9 BP 2267 EP 2274 DI 10.1023/A:1018572116447 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA WY350 UT WOS:A1997WY35000006 ER PT J AU Brook, I Frazier, EH Foote, PA AF Brook, I Frazier, EH Foote, PA TI Microbiology of chronic maxillary sinusitis: Comparison between specimens obtained by sinus endoscopy and by surgical drainage SO JOURNAL OF MEDICAL MICROBIOLOGY LA English DT Article ID MANAGEMENT AB The aerobic and anaerobic microbiology of sinus aspirates obtained during surgery was compared with culture of samples obtained by endoscopy. Six patients with chronic maxillary sinusitis were evaluated. Polymicrobial flora was found in all specimens (two-to-five isolates/sample). A total of 24 isolates (18 anaerobic, five aerobic and one microaerophilic) was obtained from sinus aspirates, and 25 isolates (16 anaerobic and nine aerobic) mere found in endoscopic specimens. The predominant organisms were Prevotella spp., Fusobacterium nucleatum, Peptostreptococcus spp. and Staphylococcus spp. Concordance in the type and concentration of organisms tvas found in all cases. Sixteen of the 18 anaerobes isolated from sinus aspirates were also found in the concomitant endoscopic sample. Five aerobic isolates mere found in both sinus aspirates and endoscopic samples and their concentration was similac. However four acrobic gram-positive bacteria (<10(4) cfu/sample) were found only in endoscopy samples. This pilot study demonstrates the usefulness of endoscopic aspiration in the isolation of bacteria from chronically infected maxillary sinuses. C1 USN HOSP,DEPT PEDIAT,BETHESDA,MD 20814. USN HOSP,DEPT INFECT DIS,BETHESDA,MD 20814. ALACHUA GEN & N FLORIDA REG HOSP,DEPT OTOLARYNGOL,GAINESVILLE,FL. NR 10 TC 29 Z9 29 U1 0 U2 0 PU CHAPMAN HALL LTD PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8HN SN 0022-2615 J9 J MED MICROBIOL JI J. Med. Microbiol. PD MAY PY 1997 VL 46 IS 5 BP 430 EP 432 PG 3 WC Microbiology SC Microbiology GA WX629 UT WOS:A1997WX62900013 PM 9152041 ER PT J AU Roland, CM Ngai, KL AF Roland, CM Ngai, KL TI Strong and fragile liquids - A brief critique - Comment SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Editorial Material ID SEGMENTAL RELAXATION; EPOXIDIZED POLYISOPRENE; TEMPERATURE-DEPENDENCE; DYNAMICS; POLYMER; MOTION; BLENDS; CHAIN AB Recently Hedge [J. Non-Cryst. Solids 202 (1996) 164] provided a brief critique of the fragility approach to interpreting the relaxation behavior of glass-forming liquids. This classification scheme has found wide applicability, bringing out the correlation between the steepness of a liquid's fragility curve and the breadth of its relaxation spectrum. The origin of this correlation can be gleaned from the coupling model of relaxation, which relates local chemical structure and intermolecular cooperativity. Since the tatter governs both time and temperature dependencies near T-g, to a substantial extent the suggestions of Hedge [J. Non-Cryst. Solids 202 (1996) 164] concerning the origin of fragility and its correlation with non-exponentiality have been anticipated by the model. RP Roland, CM (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 40 TC 28 Z9 28 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD MAY PY 1997 VL 212 IS 1 BP 74 EP 76 DI 10.1016/S0022-3093(96)00684-9 PG 3 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA XA462 UT WOS:A1997XA46200009 ER PT J AU Sarpkaya, T deAngelis, M Hanson, C AF Sarpkaya, T deAngelis, M Hanson, C TI Oscillating turbulent flow with or without a current about a circular cylinder SO JOURNAL OF OFFSHORE MECHANICS AND ARCTIC ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT 15th International Symposium and Exhibit on Offshore Mechanics and Arctic Engineering CY JUN 16-20, 1996 CL FLORENCE, ITALY SP Amer Soc Mech Engineers ID IN-LINE; NUMBERS; FORCE AB CFD analyses of two benchmark, two-dimensional, sinusoidally oscillating, turbulent flows (one with zero mean and one with nonzero mean) at relatively large Reynolds and Keulegan-Carpenter numbers and relative current velocities, have been performed with CFD-ACE, a Favre-averaged Navier-Stokes (FANS) code, The primary purpose of the investigation was a critical assessment of the the computational accuracy of time-dependent turbulent flows with large-scale unsteadiness. A number of turbulence models, including the standard k-epsilon, re-normalization group (RNG) based k-epsilon, and low-Reynolds number model have been employed. Among others, a second order in time, second order in space, second-level predictor-corrector finite-difference scheme has been used. The analysis produced the time-dependent in-line and transverse forces, the force coefficients, instantaneous velocity, vorticity, and pressure distributions, and streamlines. Representative results are compared with each other and with those obtained experimentally. RP Sarpkaya, T (reprint author), USN,POSTGRAD SCH,700 DYER RD,MONTEREY,CA 93943, USA. NR 29 TC 2 Z9 2 U1 1 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0892-7219 J9 J OFFSHORE MECH ARCT JI J. Offshore Mech. Arct. Eng. Trans. ASME PD MAY PY 1997 VL 119 IS 2 BP 73 EP 78 DI 10.1115/1.2829056 PG 6 WC Engineering, Ocean; Engineering, Mechanical SC Engineering GA XA756 UT WOS:A1997XA75600001 ER PT J AU Mansour, AE Wirsching, PH Ayyub, B White, G AF Mansour, AE Wirsching, PH Ayyub, B White, G TI Code development for ship structures - A demonstration SO JOURNAL OF OFFSHORE MECHANICS AND ARCTIC ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT 15th International Symposium and Exhibit on Offshore Mechanics and Arctic Engineering CY JUN 16-20, 1996 CL FLORENCE, ITALY SP Amer Soc Mech Engineers ID FATIGUE RELIABILITY; DESIGN; CRITERIA AB A demonstration summary of a reliability-based structural design code for ships is presented for two ship types: a cruiser and a tanker One reason for the development of such a code is to provide specifications which produce ship structure having a weight savings and/or improvement in reliability relative to structure designed by traditional methods. Another reason is to provide uniform safety margin for ships within each type. For both ship types, code requirements cover four failure modes: hull girder bulkling, unstiffened plate yielding and buckling, stiffened plate buckling, and fatigue of critical detail Both serviceability and ultimate limit states are considered. Because of limitation on the length, only hull girder modes are presented in this paper. Code requirements for other modes will be presented in future publication. A specific provision of the code will be safety check expression, which, for example, for three bending moments (still water M-s, wave M-w, and dynamic M-d), and strength M-u, might have the form, following the partial safety factor format: gamma(s)M(s) + gamma(w)M(w) + gamma(d)M(d) less than or equal to phi M-u gamma(s), gamma(w), gamma(d), and phi are the partial safety factors. The design variables (M's) are to be taken at their nominal values, typically values in the safe side of the respective distributions. Other safety check expressions for hull girder failure that include load combination factors, as well as consequence of failure factors, are considered This paper provides a summary of safety check expressions for the hull girder modes. C1 UNIV ARIZONA,TUCSON,AZ. UNIV MARYLAND,COLLEGE PK,MD 20742. USN ACAD,ANNAPOLIS,MD 21402. RP Mansour, AE (reprint author), UNIV CALIF BERKELEY,NA BLDG,ROOM 202,BERKELEY,CA 94720, USA. NR 40 TC 0 Z9 0 U1 0 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0892-7219 J9 J OFFSHORE MECH ARCT JI J. Offshore Mech. Arct. Eng. Trans. ASME PD MAY PY 1997 VL 119 IS 2 BP 114 EP 119 DI 10.1115/1.2829052 PG 6 WC Engineering, Ocean; Engineering, Mechanical SC Engineering GA XA756 UT WOS:A1997XA75600007 ER PT J AU Shin, AY Moran, ME Wenger, DR AF Shin, AY Moran, ME Wenger, DR TI Intramalleolar triplane fractures of the distal tibial epiphysis SO JOURNAL OF PEDIATRIC ORTHOPAEDICS LA English DT Article DE intramalleolar; pediatric; surgery; triplane AB The intramalleolar triplane fracture of the distal tibial epiphysis is a relatively rare injury in children. We studied five children with intramalleolar triplane fractures. Four of the five children were competitive athletes, Each child underwent computerized tomography with three-dimensional reconstruction. Delineation of the intramalleolar fracture pattern with computerized tomography with three-dimensional reconstruction demonstrated three distinct types of intramalleolar triplane fractures: I. intraarticular and within the weight-bearing zone, II. intraarticular and outside the weight-bearing zone, and III, extraarticular. Computerized tomography with three-dimensional reconstruction delineated the fracture pattern and allowed selection of the optimal treatment method. A classification scheme of the three types of intramalleolar triplane fracture is proposed. C1 USN,MED CTR,DEPT ORTHOPAED SURG,SAN DIEGO,CA 92152. UNIV CALIF SAN DIEGO,DEPT ORTHOPAED SURG,SAN DIEGO,CA 92152. OI Shin, Alexander/0000-0001-9658-8192 NR 10 TC 19 Z9 20 U1 0 U2 1 PU LIPPINCOTT-RAVEN PUBL PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 SN 0271-6798 J9 J PEDIATR ORTHOPED JI J. Pediatr. Orthop. PD MAY-JUN PY 1997 VL 17 IS 3 BP 352 EP 355 DI 10.1097/00004694-199705000-00016 PG 4 WC Orthopedics; Pediatrics SC Orthopedics; Pediatrics GA WX684 UT WOS:A1997WX68400016 PM 9150025 ER PT J AU FlippenAnderson, JL Deschamps, JR George, C Reddy, PA Lewin, AH Brine, GA Sheldrick, G Nikiforovich, G AF FlippenAnderson, JL Deschamps, JR George, C Reddy, PA Lewin, AH Brine, GA Sheldrick, G Nikiforovich, G TI X-ray structure of Tyr-D-Tic-Phe-Phe-NH2 (D-TIPP-NH2), a highly potent mu-receptor selective opioid agonist SO JOURNAL OF PEPTIDE RESEARCH LA English DT Article DE agonist; opioid peptide; peptide conformation; X-ray diffraction ID TIC-PHE-OH; CONFORMATIONAL-ANALYSIS; ENERGY PARAMETERS; PEPTIDE; ANTAGONISTS; DESIGN; POLYPEPTIDES; DIPEPTIDES AB Tyr-D-Tic-Phe-Phe-NH2 (D-TIPP), a linear tetrapeptide containing the conformationally restricted Tic residue (tetrahydroisoquinoline-3-carboxylic acid), is an opioid agonist which exhibits high affinity and selectivity for the mu-receptor. Its conformational features have been studied using a combination of solid-state (X-ray) and modeling (molecular mechanics and Monte Carlo simulations) methods. The results of the X-ray study showed two distinct conformers for D-TIPP, with the main differences lying in the orientation of the Tyr side-chain and the presence of both D-Tic(+) and D-Tic(-) conformations for the D-Tic residue. The peptide backbone is folded and stablized hi; the formation of one intramolecular hydrogen bond. The modeling results also indicated a folded backbone for the peptide and both cis and trans conformers for the D-Tic residue an found in the Lowest-energy structures. Comparison of the X-ray and modeling results shows many similarities especially around the D-Tic residue. (C) Munksgaard 1997. C1 UNIV GOTTINGEN,D-3400 GOTTINGEN,GERMANY. RES TRIANGLE INST,RES TRIANGLE PK,NC 27709. WASHINGTON UNIV,ST LOUIS,MO. RP FlippenAnderson, JL (reprint author), USN,RES LAB,STRUCT MATTER LAB,CODE 6030,WASHINGTON,DC 20375, USA. NR 22 TC 21 Z9 21 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 1397-002X J9 J PEPT RES JI J. Pept. Res. PD MAY PY 1997 VL 49 IS 5 BP 384 EP 393 PG 10 WC Biochemical Research Methods; Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA XC664 UT WOS:A1997XC66400003 PM 9211219 ER PT J AU McClean, RE Campbell, ML Kolsch, EJ AF McClean, RE Campbell, ML Kolsch, EJ TI Depletion kinetics of niobium atoms in the gas phase SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID TRANSITION-METAL ATOMS; RESONANCE-ABSORPTION SPECTROSCOPY; ABSOLUTE RATE DATA; OXIDATION REACTIONS; BONDED DINITROGEN; CHROMIUM ATOMS; TEMPERATURE; STATE; N2O; REACTIVITY AB The gas phase depletion kinetics of Nb(a(6)D(J),a(4)F(J)) in the presence of O-2, SO2, CO2, N2O, and NO are reported. Niobium atoms were produced by the 248 nm photodissociation of Nb(C5H5)(CO)(4) and detected by laser-induced fluorescence. The ground term of Nb(4d(4)5s(1)a(6)D(J)) reacts at or above the collision rate with all of the aforementioned oxidants. The first excited term, Nb(4d(3)5s(2)a(4)F(J)), is not as reactive with these oxidants. Results are interpreted in terms of long-range attractions and valence interactions. Additionally, we report reaction rate constants for ground state Nb interacting with N-2, CH4, and SF6. Nb(a(6)D(J)) is unreactive toward CH4. Nb(a(6)D(J)) + N-2 is pressure dependent at 297 K with k(0) = (2.6 +/- 0.3) x 10(-32) cm(6) s(-1) and k infinity = (4.1 +/- 0.5) x 10(-13) cm(3) s(-1). Nb(a(6)D(J)) + SF6 is temperature dependent with the rate constants given by k(T) = (1.2 +/- 0.3) x 10(-10) exp[-(4.8 +/- 0.2) kcal mol(-1)/RT] cm(3) s(-1). Depletion of the a(4)F(J) term by N-2, SF6, and CH4 is J-dependent. RP McClean, RE (reprint author), USN ACAD,DEPT CHEM,ANNAPOLIS,MD 21402, USA. NR 66 TC 27 Z9 27 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD MAY 1 PY 1997 VL 101 IS 18 BP 3348 EP 3355 DI 10.1021/jp963731n PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA WX119 UT WOS:A1997WX11900022 ER PT J AU Russell, TP Piermarini, GJ Miller, PJ AF Russell, TP Piermarini, GJ Miller, PJ TI Pressure/temperature and reaction phase diagram for dinitro azetidinium dinitramide SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID THERMAL-DECOMPOSITION; AMMONIUM DINITRAMIDE; PRESSURE; KBAR; CHEMISTRY; CELL AB The pressure/temperature and reaction phase diagram for dinitro azetidinium dinitramide (DNAZ-DN) has been delineated using a high-pressure diamond anvil cell with Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, and optical polarizing light microscopy. The phase diagram was determined between ambient pressure and 10.0 GPa over the temperature range from -75 degrees C to decomposition temperatures or > 150 degrees C, The phase diagram delineates the melt curve for alpha-DNAZ-DN, a reversible phase transformation in alpha-DNAZ-DN forming a new high-pressure polymorph, beta-DNAZ-DN, and also identifies the pressure and temperature conditions for solid state decomposition of beta-DNAZ-DN. FTIR and Raman spectra were obtained for both the alpha and beta phases as a function of pressure at room temperature. The new high-pressure beta polymorph could not be retrieved to ambient conditions. C1 NIST,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899. USN,CTR SURFACE WARFARE,SILVER SPRING,MD 20901. RP Russell, TP (reprint author), USN,RES LAB,DIV CHEM,CODE 6110,WASHINGTON,DC 20375, USA. NR 19 TC 3 Z9 3 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD MAY 1 PY 1997 VL 101 IS 18 BP 3566 EP 3570 DI 10.1021/jp962826m PG 5 WC Chemistry, Physical SC Chemistry GA WX113 UT WOS:A1997WX11300019 ER PT J AU Liu, Y Yan, XH Liu, WT Hwang, PA AF Liu, Y Yan, XH Liu, WT Hwang, PA TI The probability density function of ocean surface slopes and its effects on radar backscatter SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article ID ANALYSIS-FORECAST MODEL; WIND-GENERATED WAVES; EUROPEAN-CENTER; SCATTEROMETER DATA; IMPACT; ERS-1 AB Based on Longuet-Higgins's theory of the probability distribution of wave amplitude and wave period and on some observations, a new probability density function (PDF) of ocean surface slopes is derived. It is f(zeta(x), zeta(y)) = n/2 pi(n - 1)sigma(u) sigma(c) x [1 + zeta(x)(2)/(n - 1)sigma(n)(2) + zeta(y)(2)/(n - 1)sigma(c)(2)](-(n + 2)/2) + skewness, where zeta(x) and zeta(y) are the slope components in upwind and crosswind directions, respectively; sigma(u)(2) and sigma(c)(2) are the corresponding mean-square slopes. The peakedness of slopes is generated by nonlinear wave-wave interactions in the range of gravity waves. The skewness of slopes is generated by nonlinear coupling between the short waves and the underlying long waves. The peakedness coefficient n of the detectable surface slopes is determined by both the spectral width of the gravity waves, and the ratio between the gravity wave mean-square slope and the detectable short wave mean-square slope. When n equals 10, the proposed PDF fits the Gram Charlier distribution, given by Cox and Munk, very well in the range of small slopes. When n --> infinity, it is very close to the Gaussian distribution. Radar backscatter cross sections (RBCS), calculated from specular reflection theory using the new PDF of the C-band radar filtered surface slopes, are in keeping with empirically based ERS-1 C-band scatterometer models. In other words, the proposed PDF can be used successfully in the specular reflection theory to predict the RBCS in the range of incidence angles away from normal incidence. This suggests that the proposed PDF can be used to describe the distribution of surface slopes over the full range of slopes. This is an improvement over the Gaussian distribution and the Gram Charlier distribution. The comparison between the calculated RBCS and the ERS-1 C-band scatterometer models indicates that the peakedness coefficient n should be 5, for wind condition of U-10 less than or equal to 10 m s(-1). It is also found that the spectral width plays an important role on radar backscatter in the range of incidence angles less than 30 degrees. C1 UNIV DELAWARE,CTR REMOTE SENSING,GRAD COLL MARINE STUDIES,NEWARK,DE. CALTECH,JET PROP LAB,PASADENA,CA. USN,RES LAB,DIV OCEANOG,BAY ST LOUIS,MS 39529. RP Liu, Y (reprint author), UNIV SO MISSISSIPPI,INST MARINE SCI,BAY ST LOUIS,MS 39529, USA. NR 46 TC 28 Z9 35 U1 1 U2 5 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0022-3670 J9 J PHYS OCEANOGR JI J. Phys. Oceanogr. PD MAY PY 1997 VL 27 IS 5 BP 782 EP 797 DI 10.1175/1520-0485(1997)027<0782:TPDFOO>2.0.CO;2 PG 16 WC Oceanography SC Oceanography GA WZ308 UT WOS:A1997WZ30800011 ER PT J AU Blomshield, FS Crump, JE Mathes, HB Stalnaker, RA Beckstead, MW AF Blomshield, FS Crump, JE Mathes, HB Stalnaker, RA Beckstead, MW TI Stability testing of full-scale tactical motors SO JOURNAL OF PROPULSION AND POWER LA English DT Article ID ROCKET AB The U.S. Naval Air Warfare Center has participated in a program to develop an improved understanding of linear and nonlinear combustion instability in solid propellant rocket motors. One goal of this program was to develop a systematic database of motor and stability data. This paper describes the linear aspects of the motor firings and analysis. The motors that were used had diameters of 127 mm and were 1.7 m long. The majority were loaded with an 88% solids reduced-smoke ammonium perchlorate propellant with a nominal burning rate of 6.1 mm/s at 6.9 MPa. In addition, motors have been fired that contain 1% 8-mu m aluminum oxide, 90-mu m aluminum oxide, and 3-mu m zirconium carbide as stability additives in place of 1% ammonium perchlorate. Motor pressures ranged from 3.45 to 10.34 MPa and various grain geometries were tested. Pressure-coupled combustion response measurements were made at the nominal motor operating pressures, Motor performance and stability calculations were made using the Air Force Solid Performance Program and the Standard Stability Prediction Program for the motor configurations that were fired. The stability predictions were compared to the data obtained from the motor firings. The results indicate that it is possible to theoretically predict linear motor stability for the class of motors discussed in this paper. It was also learned that higher-pressure motors tend to be less stable and that stability additives are very effective in controlling pulsed instabilities. C1 BRIGHAM YOUNG UNIV,DEPT CHEM ENGN,PROVO,UT 84602. RP Blomshield, FS (reprint author), USN,CTR AIR WARFARE,RES & TECHNOL DIV,CHINA LAKE,CA 93555, USA. NR 16 TC 20 Z9 23 U1 0 U2 5 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAY-JUN PY 1997 VL 13 IS 3 BP 349 EP 355 DI 10.2514/2.5191 PG 7 WC Engineering, Aerospace SC Engineering GA WZ022 UT WOS:A1997WZ02200004 ER PT J AU Blomshield, FS Mathes, HB Crump, JE Beiter, CA Beckstead, MW AF Blomshield, FS Mathes, HB Crump, JE Beiter, CA Beckstead, MW TI Nonlinear stability testing of full-scale tactical motors SO JOURNAL OF PROPULSION AND POWER LA English DT Article ID ROCKET MOTORS AB The U.S. Naval Air Warfare Center has participated in a program to develop an improved understanding of linear and nonlinear combustion instability in solid propellant rocket motors. One goal of this program was to develop a systematic database of motor stability data. This paper describes the nonlinear aspects of the motor firings and analysis. The motors used had diameters of 127 mm and were 1.7 m long. The majority were loaded with are 88% solids reduced-smoke ammonium perchlorate propellant with a nominal burning rate of 6.1 mm/s at 6.9 MPa. Motor pressures ranged from 3.45 to 10.34 MPa and various grain geometries were tested. In addition, motors have been fired that contain 1% 8-mu m aluminum oxide, 90-mu m aluminum oxide, and 3-mu m zirconium carbide as stability additives in place of 1% ammonium perchlorate. This paper discusses experimental methods of motor predict and various theoretical approaches to predict pulse amplitudes in motors. The paper also examines nonlinear acoustic motor response to various amplitudes of acoustic pulsing and the resultant characteristics of sustained nonlinear oscillations. Finally, some theoretical interpretations are presented from the experimental motor data. The results show that there is a direct relationship between the dc pressure shift and the magnitude of the acoustic oscillations. C1 BRIGHAM YOUNG UNIV,PROVO,UT 84602. RP Blomshield, FS (reprint author), USN,CTR AIR WARFARE,RES & TECHNOL DIV,CHINA LAKE,CA 93555, USA. NR 15 TC 12 Z9 15 U1 0 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAY-JUN PY 1997 VL 13 IS 3 BP 356 EP 366 DI 10.2514/2.5192 PG 11 WC Engineering, Aerospace SC Engineering GA WZ022 UT WOS:A1997WZ02200005 ER PT J AU DeCredico, MA AF DeCredico, MA TI America's Civil War - Simpson,BD SO JOURNAL OF SOUTHERN HISTORY LA English DT Book Review RP DeCredico, MA (reprint author), USN ACAD,ANNAPOLIS,MD 21402, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU SOUTHERN HISTORICAL ASSOC PI ATHENS PA UNIV GEORGIA, HISTORY DEPT, ATHENS, GA 30602 SN 0022-4642 J9 J SOUTHERN HIST JI J. South. Hist. PD MAY PY 1997 VL 63 IS 2 BP 410 EP 411 DI 10.2307/2211314 PG 2 WC History SC History GA WY583 UT WOS:A1997WY58300032 ER PT J AU Laitinen, K Taramaa, J Heikkila, M Rowe, NC AF Laitinen, K Taramaa, J Heikkila, M Rowe, NC TI Enhancing maintainability of source programs through disabbreviation SO JOURNAL OF SYSTEMS AND SOFTWARE LA English DT Article ID RETRIEVAL; TAXONOMY; STYLE AB It is common to use abbreviations as names for different source program elements such as variables, constants, tables, and functions. In most cases, however, abbreviations make source programs difficult to understand and maintain. Disabbreviation means replacing abbreviated names with more informative natural names which consist of natural words. This paper presents an experimental tool to help software maintainers to disabbreviate existing source programs. The tool, which is implemented using Prolog, is an interactive and intelligent system which can suggest name replacements to its users. Common abbreviation pat terns, a specialized dictionary, and comment information are used to deduce name replacements. The tool has been evaluated by using it to disabbreviate the source programs of several existing applications. About 40% of the name substitutions suggested by the tool were acceptable in the tests. Learning to use the tool does not require much effort, and one application can be disabbreviated within a few days. (C) 1997 by Elsevier Science Inc. C1 USN,POSTGRAD SCH,DEPT COMP SCI,MONTEREY,CA 93943. RP Laitinen, K (reprint author), VTT ELECT EMBEDDED SOFTWARE,POB 1100,OULU 90571,FINLAND. NR 31 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0164-1212 J9 J SYST SOFTWARE JI J. Syst. Softw. PD MAY PY 1997 VL 37 IS 2 BP 117 EP 128 DI 10.1016/S0164-1212(96)00108-2 PG 12 WC Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA WN860 UT WOS:A1997WN86000003 ER PT J AU U, AS Toomer, B AF U, AS Toomer, B TI An expert infobase system for tracing hazardous materials in engineering documents and system requirements for materials information standardization SO JOURNAL OF TESTING AND EVALUATION LA English DT Article; Proceedings Paper CT E49 Symposium on Chemical Data Standards - Database, Data Interchange, and Information Systems CY MAY 10-11, 1995 CL COLUMBUS, OH DE materials information standardization; hazardous waste minimization; environmentally restricted materials; info structure; ASCII code limitations; expert infobase system; search indexing engine; lookup indexing engine; semantic networking AB The Hazardous Waste Minimization (HAZMIN) Infobase has a Navy Aviation Depot's maintenance directives and processing procedures in digitized text and graphics files. It is important that all chemicals that are restricted in some manner by state and federal environmental and safety regulations are identified in the materials that are specified within the processing documents, by shop (work area), and to the level of the ingredients that make up the materials in use. Described will be how, by using the HyGEN Expert Infobase System technology and appropriate methodology, an audit trail for state and federal safety- and environmentally-restricted materials can be established against engineering and material documentations. The Expert Infobase system is an integration of infobase, database, and rule-based expert systems. HyGEN software can synergistically integrate a select set of off-the-shelf PC software and can provide the system with relational capabilities such as database to text and vice versa, in addition to the common database to database. Also, there are database or text to graphics cross-relating capabilities. The system can possess similar properties as those of the object-oriented programming technology These capabilities can furthermore be synergized to successfully design and automatically manage complex information structures such as with repeating data groups nesting within another level of repeating data group. Also described will be the organizing approaches for viewing information from several perspectives yet using the same basic information set. RP U, AS (reprint author), USN,AVIAT DEPOT,MAT ENGN LAB,SAN DIEGO,CA 92135, USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 SN 0090-3973 J9 J TEST EVAL JI J. Test. Eval. PD MAY PY 1997 VL 25 IS 3 BP 341 EP 348 PG 8 WC Materials Science, Characterization & Testing SC Materials Science GA XB875 UT WOS:A1997XB87500010 ER PT J AU Maidanik, G Becker, KJ AF Maidanik, G Becker, KJ TI Double-sum technique for performing a Fourier transformation SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID PANELS AB Structural acoustics often utilizes Fourier transformation to either reveal a phenomenon that is more directly recognized in one domain than in its Fourier conjugate domain or to employ complementarity in order to decipher a phenomenon. In this paper, a novel computational technique is introduced. This technique advantageously performs this transformation in situations in which specific spatial scales govern aliased factors in the integrand of a Fourier transformation. The technique can factorially save computational steps over corresponding computations that employ discrete Fourier transform procedures. RP Maidanik, G (reprint author), NSWC,CD,DAVID TAYLOR MODEL BASIN,BETHESDA,MD 20084, USA. NR 13 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD MAY PY 1997 VL 101 IS 5 BP 2448 EP 2451 DI 10.1121/1.418487 PN 1 PG 4 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA WZ041 UT WOS:A1997WZ04100007 ER PT J AU Maidanik, G Becker, KJ AF Maidanik, G Becker, KJ TI Computation of the modal response of regularly ribbed cylinders SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID PANELS AB Recently an efficient technique was proposed for performing a Fourier transformation on integrands that are composed of aliased factors. In this paper the proposed technique is utilized to perform Fourier transformations on quantities that pertain to the response of a regularly ribbed cylinder. The computations relate to Fourier transformations from the axial wave-number domain to the axial spatial domain. The phenomena of aliasing and pass bands and stop bands are of particular interest. It is argued that the complementarity of the data, when presented in the two Fourier conjugate domains, may be a useful analytical (and experimental) tool. RP Maidanik, G (reprint author), NSWC,CD,DAVID TAYLOR MODEL BASIN,BETHESDA,MD 20084, USA. NR 17 TC 3 Z9 3 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD MAY PY 1997 VL 101 IS 5 BP 2452 EP 2472 DI 10.1121/1.418488 PN 1 PG 21 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA WZ041 UT WOS:A1997WZ04100008 ER PT J AU Yang, Y Li, YL Couchman, LS AF Yang, Y Li, YL Couchman, LS TI Solving ray acoustic problems with a DNA computer SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID SCATTERING; BIOCHIP; DEVICE AB A computational scheme that integrates the advantages of both the electronic computer and DNA computer (DNA experiment) is proposed to solve the ray acoustic problems at high frequencies. More explicitly, a conventional electronic computer is used to perform most of the sequential operations, such as solving differential equations, designing the DNA experiment, and verifying the final experimental solutions; whereas DNA annealing reaction is used to provide huge parallel operations to assemble the solutions to the scattered held for all the specified incident directions. To illustrate this idea, an example is given where the DNA reaction, rather than carrying out experimentally, is tested and simulated on an electronic computer. (C) 1997 Acoustical Society of America. C1 HUMAN GENOME SCI INC, ROCKVILLE, MD 20850 USA. USN, RES LAB, WASHINGTON, DC 20375 USA. RP SFA INC, 1401 MCCORMICK DR, LANDOVER, MD 20785 USA. NR 21 TC 0 Z9 0 U1 0 U2 0 PU ACOUSTICAL SOC AMER AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0001-4966 EI 1520-8524 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD MAY PY 1997 VL 101 IS 5 BP 2485 EP 2490 DI 10.1121/1.418490 PN 1 PG 6 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA WZ041 UT WOS:A1997WZ04100010 ER PT J AU Cederberg, RJ Collins, MD Schmidt, H Siegmann, WL AF Cederberg, RJ Collins, MD Schmidt, H Siegmann, WL TI Rational operators for filtering SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID CONSERVING PARABOLIC EQUATION; ABSORBING BOUNDARY-CONDITIONS; WAVE-EQUATION; ELASTIC MEDIA; PROPAGATION; OCEAN; ACOUSTICS; BOTTOM; DEPTH AB The parabolic equation (PE) method has been applied to approximate the wave equation, construct radiation conditions, solve scattering problems, construct initial conditions, and derive energy flux conditions. A new application of the PE method, filters based on rational approximations of depth operators, is described and tested. The rational approximation is designed to act as the identity operator on the desired part of the spectrum of the depth separated wave equation and to annihilate other parts of the spectrum. This approach does not require explicit knowledge of the spectrum. The applications of the filter include directly solving eigenvalue problems, annihilating components of the wave-number spectrum, generating initial conditions at the source range, and eliminating Gibbs oscillations that arise in energy-conserving PE solutions. (C) 1997 Acoustical Society of America. C1 MIT,CAMBRIDGE,MA 02139. RENSSELAER POLYTECH INST,TROY,NY 12180. RP Cederberg, RJ (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 28 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD MAY PY 1997 VL 101 IS 5 BP 2518 EP 2523 DI 10.1121/1.418493 PN 1 PG 6 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA WZ041 UT WOS:A1997WZ04100014 ER PT J AU Yang, TC Yoo, K AF Yang, TC Yoo, K TI Modeling the environmental influence on the vertical directionality of ambient noise in shallow water SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID SPATIAL CORRELATION; LINE ARRAYS; OCEAN; DEPTH AB The vertical directionality of acoustic ambient noise has been a subject of much interest in the past. It is a well-defined physical quantity that can be measured experimentally with a vertical array. It possesses certain deterministic features that can be modeled theoretically with environmental acoustic and source data. Ambient noise in shallow waters, including its vertical directionality, is not very well known and is also difficult to model/predict. This is because the acoustic environment varies with time and is location dependent. Thus arises the question, how does the vertical directionality of the ambient noise depend on the acoustic environments (found in typical coastal waters)? Due to the shallow water depth, it is noted that sound (noise) propagation can be significantly influenced by the bottom. The degree of bottom-interaction will depend on the sound-speed profile in the water column: whether it is downward refractive or not. Bottom attenuation will in turn determine how far the sound will propagate in the water column. Using a modal representation, a closed-form expression is obtained which can be used to interpret and predict the distant noise vertical directionality as a function of the environmental acoustic parameters. The nearby (overhead) noise is separately modeled and is found less sensitive to environmental changes as the propagation distance is short. As the deterministic features of the noise vertical directionality is controlled by the sound propagation in the channel, it could be used as an acoustic indicator of the acoustic environment in the area. Time variations of the noise directionality will also be discussed. RP USN, RES LAB, WASHINGTON, DC 20375 USA. NR 36 TC 23 Z9 28 U1 2 U2 5 PU ACOUSTICAL SOC AMER AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0001-4966 EI 1520-8524 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD MAY PY 1997 VL 101 IS 5 BP 2541 EP 2554 DI 10.1121/1.418496 PN 1 PG 14 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA WZ041 UT WOS:A1997WZ04100017 ER PT J AU Caruthers, JW Yoerger, EJ Novarini, JC AF Caruthers, JW Yoerger, EJ Novarini, JC TI Modeling low-frequency reverberation near the Mid-Atlantic ridge and comparison with ARSRP data SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB The Acoustic Reverberation Special Research Program (ARSRP) of the Office of Naval Research conducted low-frequency acoustic reverberation experiments just west of the Mid-Atlantic Ridge in 1993. Analyses of these data are supported by a bathymetric survey that produced nearly full-coverage bathymetry gridded to a resolution of 200x200m. At this scale direct-path reverberation data has been successfully modeled using Lambert's law applied to the local grazing angle determined from the high-resolution bathymetry. The analysis suggests that there could be a slightly weaker dependence on grazing angle than sine squared. The good agreement of this simple model with data shows that, for this region, two-dimensional seafloor morphology at the proper scale determines the ability to predict reverberation. For a model, such as Lambert's law, that glosses over the details of seafloor microroughness or texture at the scale the acoustic wavelength (lambda=6 m), the seafloor morphology scale that is critical is shown to be an order of magnitude or two greater than an acoustic wavelength. An average Lambert coefficient for the region is between -14 and -17 dB, but it is less than -20 dB for deeply sedimented areas and around -12 dB for rugged exposed rock areas. C1 PLANNING SYST INC,LONG BEACH,MS 39560. RP Caruthers, JW (reprint author), USN,RES LAB,BAY ST LOUIS,MS 39529, USA. NR 11 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD MAY PY 1997 VL 101 IS 5 BP 2555 EP 2565 DI 10.1121/1.418497 PN 1 PG 11 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA WZ041 UT WOS:A1997WZ04100018 ER PT J AU Dacol, DK AF Dacol, DK TI Coupled-amplitude approach to solving the Helmholtz equation SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID PROPAGATION AB The coupled-amplitude technique for solving the Helmholtz equation has been developed in the context of coupled normal modes by researchers working in a variety of wave propagation problems. In this article it is shown that this approach is not dependent on modal expansions and first-order differential equations in range for the coupled amplitudes are derived without invoking normal-mode expansions. The relationship of this exact transformation to the parabolic approximation is analyzed and numerical methods for solving the coupled-amplitude equations are discussed. The usual range-stepping algorithms used to obtain an approximate solution to the Helmholtz equation are based on the parabolic approximation and restricted to the forward propagating component of the solution. A complete solution of the Helmholtz equation in an inhomogeneous medium must also include backpropagating waves, that is, waves scattered towards the source by inhomogeneities. The inclusion of such effects in a numerically feasible full-wave approach to acoustic propagation is a problem of continual interest in the acoustics of inhomogeneous media and in ocean acoustics. The method discussed in this article addresses this difficult problem. RP Dacol, DK (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 11 TC 3 Z9 3 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD MAY PY 1997 VL 101 IS 5 BP 2566 EP 2570 DI 10.1121/1.418498 PN 1 PG 5 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA WZ041 UT WOS:A1997WZ04100019 ER PT J AU Huang, H Gaunaurd, GC AF Huang, H Gaunaurd, GC TI Acoustic scattering of a plane wave by two spherical elastic shells above the coincidence frequency SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID SOUND SCATTERING AB The acoustic scattering by two fluid-filled spherical elastic shells in close proximity to each other and insonified by plane waves at arbitrary angles of incidence is analyzed exactly in the frequency range that includes the midfrequency or coincidence enhancement region of the backscattered echoes. The incident and scattered wave fields are expanded in terms of the classical modal series and the addition theorem for the spherical wave functions is used to determine the exact expression for the sound fields scattered by each spherical elastic shell in the presence of the other, referred to coordinate systems at the centers of either spherical shell. The solution to the scattering problem is found by simultaneously solving the Helmholtz equations governing the wave motion in the fluid medium in which the two shells are submerged as well as in the fluid media contained in the shells, together with the two sets of equations of motion of the two elastic shells obtained from the complete three-dimensional elasticity theory after satisfying the boundary conditions at all fluid-shell interfaces as well as the far-field radiation condition. Again, the numerical computation of the scattered pressure wave involves the solution of a truncated ill-conditioned complex matrix system the size of which depends on how many terms of the modal series are required for convergence. This in turn depends on the value of the frequency, and on the proximity of the two spherical elastic shells. The ill-conditioned matrix equation is solved using the Gauss-Seidel iteration method. Backscattered and bistatic echoes from two identical spherical elastic shells are extensively calculated. The result also exhibits the large enhancement present in the backscattered echoes for the endfire situation after the midfrequency or coincidence enhancement has taken place. This can be attributed to the effects of focusing by the front elastic shell and to the reflection and refocusing by the back elastic shell of the a(0) Lamb wave reradiation in the observer's direction. C1 USN, CTR SURFACE WARFARE, CARDEROCK DIV, SILVER SPRING, MD 20903 USA. RP Huang, H (reprint author), USN, CTR SURFACE WARFARE, INDIAN HEAD DIV, SILVER SPRING, MD 20903 USA. NR 13 TC 14 Z9 16 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD MAY PY 1997 VL 101 IS 5 BP 2659 EP 2668 DI 10.1121/1.418507 PN 1 PG 10 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA WZ041 UT WOS:A1997WZ04100029 ER PT J AU Radlinski, RP Ko, SH AF Radlinski, RP Ko, SH TI Flexural wave reduction using a compliant tube baffle - Signal pressure received by a hydrophone placed on a plate backed by a compliant baffle - Comments SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Letter ID SCATTERING; GRATINGS AB The cited formulations for studying the baffling of flexural waves by a compliant tube grating [S. H. Ko, J. Acoust. Sec. Am. 99, 691-699 (1996)] and for determining the acoustic receive sensitivity of a hydrophone placed near a plate backed by a compliant tube grating [S. H. Ko and PI. H. Schloemer, J. Acoust. Sec. Am. 89, 559-564 (1991)] are dependent on the validity of the lumped-fluid parameter approximations developed by Junger [M. C. Junger, J. Acoust. Soc. Am. 78, 1010-1012 (1985)] for a grating of closely spaced compliant tubes between two semi-infinite fluid half-spaces. If the fluid between the plate and the grating is great enough to minimize their interaction, the incorporation of the effective layer parameters developed by Junger should be reasonably valid. Unfortunately, the sample calculations in Ko (Ref. 4) and Ko and Schloemer (Ref. 5) have been made for the limiting case of the compliant tube grating in direct contact with the plates where the use of Junger's approximations is inappropriate. RP Radlinski, RP (reprint author), USN,UNDERSEA WARFARE CTR,NEWPORT,RI 02841, USA. NR 9 TC 0 Z9 0 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD MAY PY 1997 VL 101 IS 5 BP 2978 EP 2979 DI 10.1121/1.419477 PN 1 PG 2 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA WZ041 UT WOS:A1997WZ04100059 ER PT J AU Graham, BS Barrett, TL AF Graham, BS Barrett, TL TI Solitary painful piezogenic pedal papule SO JOURNAL OF THE AMERICAN ACADEMY OF DERMATOLOGY LA English DT Article; Proceedings Paper CT Gross and Microscopic Section of the American-Academy-of-Dermatology Annual Meeting CY FEB 10-11, 1996 CL WASHINGTON, DC SP Amer Acad Dermatol, Gross & Microscop Sect, USN, The Chief, Bur Med & Surg C1 USN,MED CTR,DEPT DERMATOL,SAN DIEGO,CA 92134. RP Graham, BS (reprint author), USN,MED CTR,DEPT CLIN INVEST,34800 BOB WILSON DR,SAN DIEGO,CA 92134, USA. NR 4 TC 4 Z9 4 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 SN 0190-9622 J9 J AM ACAD DERMATOL JI J. Am. Acad. Dermatol. PD MAY PY 1997 VL 36 IS 5 BP 780 EP 781 DI 10.1016/S0190-9622(97)80346-5 PN 1 PG 2 WC Dermatology SC Dermatology GA WX860 UT WOS:A1997WX86000018 PM 9146543 ER PT J AU Shi, JJ Chang, S Raman, S AF Shi, JJ Chang, S Raman, S TI Interaction between Hurricane Florence (1988) and an upper-tropospheric westerly trough SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID SEASON TYPHOON DEVELOPMENT; ANGULAR-MOMENTUM FLUXES; TROPICAL CYCLONE; EXTERNAL INFLUENCES; ENVIRONMENTAL FLOW; OUTFLOW LAYER; INTENSITY; MODEL; INTENSIFICATION AB The Naval Research Laboratory's limited-area numerical prediction system, a version of Navy Operational Regional Atmospheric Prediction System, was used to investigate the interaction between Hurricane Florence (1988) and its upper-tropospheric environment. The model was initialized with the National Meteorological Center (now the National Centers for Environmental Prediction)/Regional Analysis and Forecasting Systems 2.5 degrees analysis at 0000 UTC 9 September 1988, enhanced by a set of Omega dropwindsonde data through a three-pass nested-grid objective analysis. Diagnosis of the 200-mb level structure of the 12-h forecast valid for 1200 UTC 9 September 1988 showed that the outflow layer was highly asymmetric with an outflow jet originating at approximately 3 degrees north of the storm. In agreement with the result of an idealized simulation (Shi et al. 1990), there was a thermally direct, circum-jet secondary circulation in the jet entrance region and a thermally indirect one in a reversed direction in the jet exit region. In several previous studies, it was postulated that an approaching westerly jet had modulated the convection and intensity variations of Florence. Tn a variational numerical experiment in this study, the approaching westerly jet was flattened out by repeatedly setting the jet-level meridional wind component and zonal temperature perturbations to zero in the normal mode initialization procedure. Compared with the control experiment, the variational experiment showed that the sudden burst of Florence's inner core convection was highly correlated with the approaching upper-tropospheric westerly jet. These experiments also suggested that the approaching upper-tropospheric westerly jet was crucial to the intensification of Florence's inner core convection between 1000 and 1500 UTC 9 September, which occurred prior to the deepening of the minimum sea level pressure (from 997 to 987 mb) between 1200 UTC 9 September and 0000 UTC 10 September. Many earlier studies have attempted an explanation for the effect on tropical cyclones of upper-tropospheric forcings from the eddy angular momentum approach. The result of this study provides an alternative but complementary mechanism of the interaction between an upper-level westerly trough and a tropical cyclone. C1 SCI APPLICAT INT CORP,MCLEAN,VA 22102. USN,RES LAB,MONTEREY,CA. N CAROLINA STATE UNIV,DEPT MARINE EARTH & ATMOSPHER SCI,RALEIGH,NC 27695. NR 45 TC 17 Z9 18 U1 2 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD MAY 1 PY 1997 VL 54 IS 9 BP 1231 EP 1247 DI 10.1175/1520-0469(1997)054<1231:IBHFAA>2.0.CO;2 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA WX110 UT WOS:A1997WX11000008 ER PT J AU Lynch, JE Pehrsson, PE Leonard, DN Calvert, JM AF Lynch, JE Pehrsson, PE Leonard, DN Calvert, JM TI Interfacial electrical properties of electroless Ni contacts formed using self-assembling monolayers on silicon SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID METALLIZATION; DEPOSITION; FILMS AB A new, additive, substrate metallization process, useful for high resolution lithography and microelectronic circuit fabrication has been developed. The process, which involves surface modification with a self-assembled monolayer (SAM) film, selective binding of a catalytic Pd colloid, and electroless (EL) metal deposition, was used to deposit EL Ni on p-type (100) silicon substrates with a native oxide layer. The deposits were characterized by current-potential (I-V) and capacitance-potential (C-V) measurements. and were compared to evaporatively deposited Ni films. Schottky barrier heights for both the EL and evaporated Wi contacts ranged between 0.6 to 0.7 eV; similar to 0.1 to 0.2 eV higher than the typical value for Wi on atomically clean p-type silicon, as expected for contacts separated from the substrate by a thin insulating layer. The similarity of the EL and evaporated Ni barrier heights indicates that the buried organic SAM film and the Pd catalyst did not significantly alter the interfacial electrical characteristics. Heating the EL Ni deposits to over 300 degrees C reduced the Schottky barrier height and increased the leakage current, although less so than on the evaporated contacts. C1 GEORGE MASON UNIV,DEPT PHYS & ASTRON,FAIRFAX,VA 22030. USN,RES LAB,CTR BIOMOL SCI & ENGN,WASHINGTON,DC 20375. GEOCENTERS INC,FT WASHINGTON,MD 20744. RP Lynch, JE (reprint author), USN,RES LAB,DIV CHEM,WASHINGTON,DC 20375, USA. NR 21 TC 7 Z9 7 U1 0 U2 1 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD MAY PY 1997 VL 144 IS 5 BP 1698 EP 1703 DI 10.1149/1.1837663 PG 6 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA XD006 UT WOS:A1997XD00600042 ER PT J AU Overfelt, PL AF Overfelt, PL TI Generation of a Bessel-Gauss pulse from a moving disk source distribution SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION LA English DT Article ID SCALAR WAVE-EQUATION; BEAMS; MODES AB Assuming a moving disk source distribution, the Riemann method and Gegenbauer's addition theorem in a mixed coordinate-space-phase-space formulation have been used to derive a zeroth-order Bessel-Gauss pulse solution to the inhomogeneous wave equation. In the region where tau(2) greater than or similar to rho(eff)(2) + z(2), the total solution can be separated into a wave that attenuates quickly and a Bessel-Gauss pulse that exists only after a certain time and continues for long times. In the region where z(2) less than or equal to tau(2) less than or similar to rho(eff)(2) + z(2), only a short-time solution exists. (C) 1997 Optical Society of America. RP Overfelt, PL (reprint author), USN,AIR WARFARE CTR,WEAP DIV,RES & TECHNOL GRP,PHYS BRANCH,CHINA LAKE,CA 93555, USA. NR 19 TC 9 Z9 9 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0740-3232 J9 J OPT SOC AM A JI J. Opt. Soc. Am. A-Opt. Image Sci. Vis. PD MAY PY 1997 VL 14 IS 5 BP 1087 EP 1091 DI 10.1364/JOSAA.14.001087 PG 5 WC Optics SC Optics GA WV712 UT WOS:A1997WV71200015 ER PT J AU DeCredico, MA AF DeCredico, MA TI Image and reality - Ken Burns and the Urban Confederacy SO JOURNAL OF URBAN HISTORY LA English DT Article RP DeCredico, MA (reprint author), USN ACAD,ANNAPOLIS,MD 21402, USA. NR 35 TC 1 Z9 1 U1 0 U2 0 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 SN 0096-1442 J9 J URBAN HIST JI J. Urban Hist. PD MAY PY 1997 VL 23 IS 4 BP 387 EP 405 DI 10.1177/009614429702300401 PG 19 WC History; History Of Social Sciences; Urban Studies SC History; Social Sciences - Other Topics; Urban Studies GA WY834 UT WOS:A1997WY83400001 ER PT J AU Powell, CR Huisman, TK Riffenburgh, RH Saunders, EL Bethel, KJ Johnstone, PAS AF Powell, CR Huisman, TK Riffenburgh, RH Saunders, EL Bethel, KJ Johnstone, PAS TI Outcome for surgically staged localized prostate cancer treated with external beam radiation therapy SO JOURNAL OF UROLOGY LA English DT Article; Proceedings Paper CT 91st Annual Meeting of the American-Urological-Association CY MAY 04-09, 1996 CL ORLANDO, FL SP Amer Urol Assoc DE prostatic neoplasms; neoplasm staging; radiotherapy ID LYMPH-NODE DISSECTION; RADICAL PROSTATECTOMY; ADENOCARCINOMA; CARCINOMA; RADIOTHERAPY; IRRADIATION; MANAGEMENT; SURVIVAL; PATTERN; ANTIGEN AB Purpose: A retrospective analysis was performed on patients with surgically staged localized prostate cancer treated with external beam radiation therapy for 10-year overall, cause specific and disease-free survivals based on lack of clinical recurrence and 2 separate prostate specific antigen criteria for cure. Materials and Methods: We analyzed 145 patients who received external beam radiation therapy after a negative staging pelvic lymphadenectomy for prostate cancer. Followup data were available for 129 patients (90%). Disease was stage A in 29 patients (22.5%), stage B in 64 (49.6%), stage B2/C in 2 (17%) and stage C in 14 (10.9%). Average potential followup from date of diagnosis was 11.5 years (minimum 7.2). Of the patients 87 potentially can be followed for longer than 10 years. Disease-free survival was based on a normal digital rectal examination, lack of symptoms suspicious for metastasis and application of 2 separate prostate specific antigen criteria of 4 ng./ml. or less (group 1), or 1.5 ng./ml. or less (group 2), Survival was analyzed with the Kaplan-Meier actuarial method. Results: Actuarial overall survival at 10 and 15 years was 63.7 and 49.6, respectively, and cause specific survival was 84.2 and 80%, respectively. Disease-free survival was 54.5 and 32.4%, respectively, for group 1, and 42.3 and 9.6%, respectively, for group 2. Conclusions: The improved patient selection inherent in surgical staging before definitive external beam radiation therapy provides for improved overall and cause specific survival over that of patients without surgical staging. Biochemical disease-free survival also appears to be improved. C1 USN,MED CTR,DEPT UROL,SAN DIEGO,CA 92134. USN,MED CTR,DEPT LAB,DIV PATHOL,SAN DIEGO,CA 92134. USN,MED CTR,DEPT RADIOL,DIV RADIAT ONCOL,SAN DIEGO,CA 92134. UNIV CALIF SAN DIEGO,DIV RADIAT ONCOL,SAN DIEGO,CA 92103. RP Powell, CR (reprint author), USN,MED CTR,DEPT CLIN INVEST,34800 BOB WILSON DR,SAN DIEGO,CA 92134, USA. NR 21 TC 23 Z9 23 U1 0 U2 0 PU WILLIAMS & WILKINS PI BALTIMORE PA 351 WEST CAMDEN ST, BALTIMORE, MD 21201-2436 SN 0022-5347 J9 J UROLOGY JI J. Urol. PD MAY PY 1997 VL 157 IS 5 BP 1754 EP 1758 DI 10.1016/S0022-5347(01)64854-7 PG 5 WC Urology & Nephrology SC Urology & Nephrology GA WU178 UT WOS:A1997WU17800065 PM 9112521 ER PT J AU Cilento, BG Stock, JA Kaplan, GW AF Cilento, BG Stock, JA Kaplan, GW TI Pantaloon spica cast: An effective method for postoperative immobilization after free graft hypospadias repair SO JOURNAL OF UROLOGY LA English DT Article DE hypospadias; tissue transplantation; postoperative care; penis; graft survival AB Purpose: We used a postoperative dressing of silicone foam in conjunction with a pantaloon spica cast to optimize the chances for successful graft take in hypospadias repairs with grafts. We compared the results to those of inpatient bed restriction. Materials and Methods: A total of 15 patients underwent graft urethroplasty, and application of a penile silicone foam dressing and fiberglass pantaloon spica cast. Patients were discharged home the following morning. Results: Two fistulas developed. Results are no different from those of our previously reported cases which required 6 or 7 days of hospitalization. Conclusions: We believe that the pantaloon spica cast provides necessary immobilization for facilitating imbibition and inosculation, which are required for graft survival. Also, the spica cast allows early discharge home, obviating the need for prolonged hospitalization and bed rest. C1 UNIV CALIF SAN DIEGO,MED CTR,CTR HLTH,SAN DIEGO,CA 92103. UNIV CALIF SAN DIEGO,MED CTR,DIV UROL,SAN DIEGO,CA 92103. USN,MED CTR,DEPT UROL,SAN DIEGO,CA 92152. RP Cilento, BG (reprint author), UNIV CALIF SAN DIEGO,CHILDRENS HOSP,MED CTR,SAN DIEGO,CA 92103, USA. NR 4 TC 6 Z9 6 U1 0 U2 0 PU WILLIAMS & WILKINS PI BALTIMORE PA 351 WEST CAMDEN ST, BALTIMORE, MD 21201-2436 SN 0022-5347 J9 J UROLOGY JI J. Urol. PD MAY PY 1997 VL 157 IS 5 BP 1882 EP 1883 DI 10.1016/S0022-5347(01)64892-4 PG 2 WC Urology & Nephrology SC Urology & Nephrology GA WU178 UT WOS:A1997WU17800103 PM 9112554 ER PT J AU Brizzolara, RA Boyd, JL Tate, AE AF Brizzolara, RA Boyd, JL Tate, AE TI Evidence for covalent attachment of purple membrane to a gold surface via genetic modification of bacteriorhodopsin SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 43rd American-Vacuum-Society Symposium CY OCT 14-18, 1996 CL PHILADELPHIA, PA SP Amer Vacuum Soc ID SELF-ASSEMBLED MONOLAYERS; FILMS AB The objective of this work is to covalently attach bacteriorhodopsin (BR) to a gold surface via genetic substitution of cysteine for serine (S35C) at the 35th amino acid position. Samples of PR-containing purple membrane (PM) on gold were evaluated using atomic force microscopy (AFM) and x-ray photoelectron spectroscopy (XPS). AFM images reveal a surface coverage of S35C-containing PM fragments of approximately 25%. XPS measurements reveal a small excess of sulfur for S35C-containing PM on gold, and a much larger excess of sulfur on wildtype-containing PM on gold. In both cases, the excess sulfur is covalently bound to the gold surface and appears to originate from dissociated methyl mercaptan groups from methionine residues on the external surfaces of BR. We conclude that the quantity of excess sulfur is smaller for S35C than for wildtype because the S35C's sulfhydryl binds some PM fragments to the surface, reducing the quantity of methyl mercaptan that can bind to the surface. It then follows that the rather low coverage of S35C-containing PM fragments on gold is due to interference of the methyl mercaptan groups with the binding of S35C-containing PM fragments to the surface. Coverage might be increased by immobilizing S35C-containing fragments on a functionalized surface using a heterobifunctional cross-linker, thereby preventing dissociation of methyl mercaptan groups from BR, and by using smaller PM fragments. (C) 1997 American Vacuum Society. C1 USN,CTR SURFACE WARFARE,DAHLGREN DIV,DAHLGREN,VA 22448. RP Brizzolara, RA (reprint author), USN,CTR SURFACE WARFARE,CARDEROCK DIV,CODE 684,BETHESDA,MD 20817, USA. NR 22 TC 13 Z9 13 U1 1 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1997 VL 15 IS 3 BP 773 EP 778 DI 10.1116/1.580706 PN 1 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA XE731 UT WOS:A1997XE73100060 ER PT J AU Sinnott, SB Colton, RJ White, CT Shenderova, OA Brenner, DW Harrison, JA AF Sinnott, SB Colton, RJ White, CT Shenderova, OA Brenner, DW Harrison, JA TI Atomistic simulations of the nanometer-scale indentation of amorphous-carbon thin films SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 43rd American-Vacuum-Society Symposium CY OCT 14-18, 1996 CL PHILADELPHIA, PA SP Amer Vacuum Soc ID DIAMOND-LIKE CARBON; MOLECULAR-DYNAMICS SIMULATIONS; FRICTION FORCE MICROSCOPY; CHEMICAL VAPOR-DEPOSITION; MECHANICAL-PROPERTIES; TUNGSTEN TIP; SURFACE; ADHESION; SCATTERING; TRIBOLOGY AB Molecular dynamics simulations are used to examine the nanometer-scale indentation of a thin film of amorphous carbon with a nonrigid sp(3) bonded carbon tip. The simulations show in detail the atomic-scale mechanism of the indentation process and compare the bonding character of the film before and after indentation. The computationally determined elastic modulus of the amorphous-carbon film is found to be 243 GPa, in good agreement with experiment. (C) 1997 American Vacuum Society. C1 USN,RES LAB,DIV CHEM,WASHINGTON,DC 20375. N CAROLINA STATE UNIV,DEPT MAT SCI & ENGN,RALEIGH,NC 27695. USN ACAD,DEPT CHEM,ANNAPOLIS,MD 21402. RP Sinnott, SB (reprint author), UNIV KENTUCKY,DEPT CHEM & MAT ENGN,LEXINGTON,KY 40506, USA. RI Brenner, Donald/D-1741-2009; Sinnott, Susan/P-8523-2014 OI Sinnott, Susan/0000-0002-3598-0403 NR 39 TC 35 Z9 35 U1 2 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1997 VL 15 IS 3 BP 936 EP 940 DI 10.1116/1.580782 PN 1 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA XE731 UT WOS:A1997XE73100090 ER PT J AU Godbey, DJ Ancona, MG AF Godbey, DJ Ancona, MG TI Modeling of Ge segregation in the limits of zero and infinite surface diffusion SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 43rd American-Vacuum-Society Symposium CY OCT 14-18, 1996 CL PHILADELPHIA, PA SP Amer Vacuum Soc ID MOLECULAR-BEAM EPITAXY; SIGE BURIED LAYER; GROWTH; HETEROSTRUCTURES; TEMPERATURE; DEPENDENCE; SI(001) AB A model to treat Ge segregation with simultaneous growth and exchange during Si/SiGe layer growth by molecular beam epitaxy is described. Within this three layer formalism, the segregating layers were treated in two limiting cases, a solid surface model in which no surface diffusion occurs, and a fluid surface model, in which surface diffusion is very fast. Simultaneous treatment of exchange and growth within the fluid surface model was the only one of the two that allowed the accumulation of Ge in the top two layers to significantly exceed that of the bulk in surface alloys, in agreement with experimental observations. RP Godbey, DJ (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 15 TC 18 Z9 18 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1997 VL 15 IS 3 BP 976 EP 980 DI 10.1116/1.580790 PN 1 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA XE731 UT WOS:A1997XE73100099 ER PT J AU Brandow, SL Calvert, JM Snow, ES Campbell, PM AF Brandow, SL Calvert, JM Snow, ES Campbell, PM TI Metal pattern fabrication using the local electric field of a conducting atomic force microscope probe SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 43rd American-Vacuum-Society Symposium CY OCT 14-18, 1996 CL PHILADELPHIA, PA SP Amer Vacuum Soc ID SCANNING TUNNELING MICROSCOPE; TIP-INDUCED ANODIZATION; EFFECT TRANSISTORS; SI NANOSTRUCTURES; SILICON; SURFACES; DEPOSITION; OXIDATION; SI(100); FILMS AB Two approaches were developed using an ambient atomic force microscope (AFM) to pattern metal in either positive or negative tone. The difference in surface chemical reactivity between exposed and unexposed regions was used to selectively attach colloidal Pd(II) nanoparticles capable of initiating the deposition of electroless (EL) Ni. In one case, EL Ni was selectively deposited in the unexposed regions of an organosilane film. In the second case, EL Ni was selectively deposited directly on an AFM oxide pattern. Based on the different binding selectivities of the Pd(II) catalysts, selective deposition on AFM patterns was attributed to the presence of a carbon residue in AFM oxide patterns formed under ambient conditions. The patterned Ni films were used as a mask for pattern transfer into the underlying substrate by reactive ion etching. (C) 1997 American Vacuum Society. C1 USN,RES LAB,DIV ELECT SCI & TECHNOL,WASHINGTON,DC 20375. RP Brandow, SL (reprint author), USN,RES LAB,CTR BIOMOL SCI & ENGN,WASHINGTON,DC 20375, USA. NR 22 TC 27 Z9 27 U1 1 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1997 VL 15 IS 3 BP 1455 EP 1459 DI 10.1116/1.580561 PN 2 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA XE732 UT WOS:A1997XE73200062 ER PT J AU Singh, DJ AF Singh, DJ TI Intermixing in Fe/Cr (001) multilayers: Density functional calculations SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 43rd American-Vacuum-Society Symposium CY OCT 14-18, 1996 CL PHILADELPHIA, PA SP Amer Vacuum Soc ID LAYERED MAGNETIC-STRUCTURES; GIANT MAGNETORESISTANCE; EXCHANGE; SUPERLATTICES; OSCILLATIONS; FE(100); FE/CR/FE(100); MOMENTS; FILMS AB Fe/Cr (001) multilayers containing perfect as well as intermixed interfaces were investigated using density functional calculations and an ordered supercell approach. The results show that the qualitative differences between theoretical expectations for perfect interfaces and experimental data for real Fe/Cr multilayers can be understood in terms of intermixing. Both phase shifts and reductions in magnitude of the coupling are found. RP Singh, DJ (reprint author), USN,RES LAB,COMPLEX SYST THEORY BRANCH,WASHINGTON,DC 20375, USA. RI Singh, David/I-2416-2012 NR 29 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1997 VL 15 IS 3 BP 1770 EP 1773 DI 10.1116/1.580867 PN 2 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA XE732 UT WOS:A1997XE73200119 ER PT J AU Buckley, LJ Snow, AW Hu, HS Griffith, J Ray, M AF Buckley, LJ Snow, AW Hu, HS Griffith, J Ray, M TI Development of a low permittivity fluorinated copolymer for interlevel dielectric applications SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID POLYIMIDE FILMS; BCB AB Technology for future integrated circuits will require advances in all facets of materials and processing. Low dielectric constant materials will require advances in electrical, thermal, and mechanical behavior before process integration can occur, The dielectric constant must be lower than that of amorphous silicon dioxide and possess the right properties for integration with future metallurgies such as copper. Several organic thermoset resins that were predicted to possess the necessary characteristics have been synthesized and studied. A thermoset copolymer of 1,3,5-tris(2-allyloxy-hexafluoro-2-propyl) benzene with polymethylhydrosiloxane oligomers was identified as a material worthy of further development. Thermal gravimetric analysis indicates relative stability up to 350 degrees C for short periods of time (30-60 min). The complex permittivity was measured up to 40 GHz and was found to be 2.40 with a loss tangent of 0.008. Compatibility with copper multilevel processing was determined by a secondary ion mass spectroscopy analysis. Copper ion migration did not occur. The processability of the dielectric resins was investigated to address the integration issues associated with the fabrication process. (C) 1997 American Vacuum Society. C1 GEOCENTERS INC,FT WASHINGTON,MD 20744. USN,RES LAB,DIV CHEM,WASHINGTON,DC 20375. MCNC,RES TRIANGLE PK,NC 27709. RP Buckley, LJ (reprint author), USN,RES LAB,DIV CHEM,WASHINGTON,DC 20375, USA. NR 14 TC 1 Z9 1 U1 1 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 1997 VL 15 IS 3 BP 741 EP 745 DI 10.1116/1.589379 PG 5 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA XF134 UT WOS:A1997XF13400036 ER PT J AU Soliman, AK Watts, DM Salib, AW Shehata, AED Arthur, RR Botros, BAM AF Soliman, AK Watts, DM Salib, AW Shehata, AED Arthur, RR Botros, BAM TI Application of an immunoperoxidase monolayer assay for the detection of arboviral antibodies SO JOURNAL OF VIROLOGICAL METHODS LA English DT Article DE immunoperoxidase monolayer assay; ELISA; arboviruses; Rift Valley fever virus; West Nile virus; Dengue virus; Sandfly fever virus; Yellow fever virus ID LINKED-IMMUNOSORBENT-ASSAY; RIFT-VALLEY FEVER; MONOCLONAL-ANTIBODIES; VIRUS-INFECTION; DISEASE; PIGS AB An immunoperoxidase monolayer assay (IPMA) was adapted for the detection of antibodies to six arboviruses: three viruses within the flavivirus group (dengue 2, West Nile (WN) and yellow fever) and three in the phlebovirus group (Rift Valley fever (RVF), sandfly fever Naples and sandfly fever Sicilian). Antibody titers of homologous hyper-immune mouse ascitic fluid (HMAF) measured by IPMA were two to eight-fold less than those determined by ELISA. In tests with heterologous HMAF, cross-reactions frequently observed in ELISA, particularly in the flavivirus group, were absent in all IPMA titrations. With human serum samples tested for antibodies to RVF (n = 52) and WN (n = 90), the sensitivity of IPMA as compared with ELISA was 96 and 91%, respectively, specificity of IPMA was 100%. In addition, the IPMA format has several advantages that make it a useful alternative to ELISA for diagnosing arboviral infections under field conditions. (C) 1997 Elsevier Science B.V. C1 USN,MED RES UNIT 3,VIROL BRANCH,CAIRO,EGYPT. USN,MED RES INST DETACHMENT,LIMA,PERU. JOHNS HOPKINS UNIV,SCH HYG & PUBL HLTH,BALTIMORE,MD. NR 15 TC 10 Z9 10 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-0934 J9 J VIROL METHODS JI J. Virol. Methods PD MAY PY 1997 VL 65 IS 2 BP 147 EP 151 DI 10.1016/S0166-0934(97)02185-X PG 5 WC Biochemical Research Methods; Biotechnology & Applied Microbiology; Virology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Virology GA XC316 UT WOS:A1997XC31600001 PM 9186937 ER PT J AU Machado, PH AF Machado, PH TI Politics and judgment in federal district courts - Rowland,CK, Carp,RA SO JUDICATURE LA English DT Book Review RP Machado, PH (reprint author), USN ACAD,ANNAPOLIS,MD 21402, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMERICAN JUDICATURE SOCIETY PI CHICAGO PA 180 N MICHIGAN AVE, SUITE 600, CHICAGO, IL 60601-7401 SN 0022-5800 J9 JUDICATURE JI Judicature PD MAY-JUN PY 1997 VL 80 IS 6 BP 294 EP 296 PG 3 WC Law SC Government & Law GA XK671 UT WOS:A1997XK67100014 ER PT J AU Beadle, A AF Beadle, A TI Ciguatera fish poisoning SO MILITARY MEDICINE LA English DT Article ID CIGUATOXIN; CALIFORNIA; SEVERITY; MANNITOL AB Ciguatera fish poisoning is the most common form of toxin-related food poisoning in the United States. Originating from dinoflagellates living on coral reefs, it is spread up the food chain and affects humans who ingest the ciguatoxic fish. Ciguatera is primarily endemic in tropical regions of the world. It is a self-limiting disease that presents with characteristic gastrointestinal, neurological, and cardiovascular symptoms, Recent advances in testing procedures and symptom recognition has improved ciguatoxin identification and clinical management. However, there is still a need for better diagnostic, preventive, and reporting protocols to more accurately study and understand this diverse and temporarily debilitating clinical syndrome. RP Beadle, A (reprint author), NAVAL MED CTR PORTSMOUTH,INTENS CARE UNIT,620 JOHN PAUL JONES CIRCLE,PORTSMOUTH,VA 23708, USA. NR 31 TC 6 Z9 6 U1 0 U2 1 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 SN 0026-4075 J9 MIL MED JI Milit. Med. PD MAY PY 1997 VL 162 IS 5 BP 319 EP 322 PG 4 WC Medicine, General & Internal SC General & Internal Medicine GA WZ087 UT WOS:A1997WZ08700005 PM 9155099 ER PT J AU Rollwagen, FM Li, YYY Pacheco, ND Baqar, S AF Rollwagen, FM Li, YYY Pacheco, ND Baqar, S TI Systemic sepsis following hemorrhagic shock: Alleviation with oral interleukin-6 SO MILITARY MEDICINE LA English DT Article ID BACTERIAL TRANSLOCATION; EPITHELIAL-CELLS; IMMUNOSUPPRESSION; GUT AB Gut-origin sepsis is a serious medical complication of military injuries following hemorrhage, Splanchnic ischemia induces intestinal necrosis leading to systemic bacteremia. Rat and mouse models of hemorrhagic shock were used to investigate bacterial translocation from the gut. Orally administered ameliorative treatments using the cytokine interleukin-6 (IL-6) were able to reduce or eliminate sepsis following hemorrhage. To mimic battlefield wounds and hemorrhage, anesthetized mice were bled from the femoral artery, held at a mean arterial blood pressure of 35 mm Hg for 1 hour, and then resuscitated with shed blood and a-fold volume lactated Ringer's solution, Anesthetized rats were bled from the carotid artery at a rate of 15 ml/kg at 1 ml/minute, Bacteriological cultures of livers and mesenteric lymph nodes from hemorrhaged animals given recombinant IL-6 had significantly fewer colonies per gram of tissue than saline-fed controls. I-125-labeled IL-6 remained in the gut for up to 6 hours giving regional protection, whereas labeled interleukin-a was disseminated throughout the body in the same time, In vivo and in vitro studies of IL-6 showed that long incubations with high doses of trypsin, chymotrypsin, or intestinal contents were necessary to inactivate the bioactivity of this cytokine, Electron microscopy showed that epithelial cells from hemorrhaged mice fed saline had sparse or missing villi and vacuolated cytoplasm. Epithelial cells from control mice or mice hemorrhaged and fed cytokine appeared completely normal. Oral administration of IL-6 on the battlefield may be an important treatment for the prevention of sepsis following hemorrhage. RP Rollwagen, FM (reprint author), USN,MED RES INST,WOUND REPAIR ENHANCEMENT PROGRAM,8901 WISCONSIN AVE,BETHESDA,MD 20889, USA. NR 17 TC 17 Z9 17 U1 0 U2 1 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 SN 0026-4075 J9 MIL MED JI Milit. Med. PD MAY PY 1997 VL 162 IS 5 BP 366 EP 370 PG 5 WC Medicine, General & Internal SC General & Internal Medicine GA WZ087 UT WOS:A1997WZ08700017 PM 9155111 ER PT J AU Holtz, RL Provenzano, V AF Holtz, RL Provenzano, V TI Bounds on the strength of a model nanocomposite SO NANOSTRUCTURED MATERIALS LA English DT Article ID ZENER DRAG; PARTICLES; ALLOYS AB Criteria for thermally stable, high-strength metallic nanocomposites in the context of Hall-Petch behavior of the constituent phases are examined. It is argued that both upper and lower bounds exist on the strength of such nanocomposites as a function of volume fraction and particle size of the component phases. Using a two-phase topological model, assuming Hall-Fetch behaviors for the pure constituent phases, and accounting for thermally stable grain sizes in the context of the Zener drag model, we predict that an optimal combination of nanostructured particles in a metal matrix would consist of nanoscale particles with a volume fraction of about 25%, dispersed in a matrix of a metal with a high Hall-Fetch coefficient, and the two phases being immiscible. The matrix phase grains would necessarily be up to ten times larger than the dispersed phase particle size, as a result of the trade-off of grain size stabilization versus Hall-Fetch strengthening. (C) 1997 Acta Metallurgica Inc. C1 USN,RES LAB,DIV MAT SCI & TECHNOL,WASHINGTON,DC 20375. RP Holtz, RL (reprint author), GEOCENTERS INC,10903 INDIAN HEAVY HWY,FT WASHINGTON,MD 20744, USA. NR 11 TC 4 Z9 4 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0965-9773 J9 NANOSTRUCT MATER JI Nanostruct. Mater. PD MAY-JUN PY 1997 VL 8 IS 3 BP 289 EP 300 DI 10.1016/S0965-9773(97)00172-4 PG 12 WC Materials Science, Multidisciplinary SC Materials Science GA XA594 UT WOS:A1997XA59400004 ER PT J AU Scott, RJ Gauthier, M Sorber, K Pennisi, J Robinson, P Hough, M AF Scott, RJ Gauthier, M Sorber, K Pennisi, J Robinson, P Hough, M TI Acquisition reform in transition: Where are we going, how do we get there? SO NAVAL ENGINEERS JOURNAL LA English DT Editorial Material RP Scott, RJ (reprint author), USN,WASHINGTON,DC 20350, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 65 EP 82 PG 18 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700003 ER PT J AU Sikora, J Grassman, JM Sensharma, P Watts, J AF Sikora, J Grassman, JM Sensharma, P Watts, J TI Advanced double hull structural design technology SO NAVAL ENGINEERS JOURNAL LA English DT Article; Proceedings Paper CT American-Society-of-Naval-Engineers Day 1997 CY MAR 18, 1997 CL WASHINGTON, DC SP Amer Soc Naval Engineers AB The Mid-Term Sealift Ship Technology Development Program is a multiyear research and development effort to examine promising technologies for application to construction of sealift ships. One of the goals of this program is to enhance the competitiveness of U.S. shipbuilders by investigating a new method of hull construction that would be easier and cheaper to build and preoutfit. The concept consists of a long-spanned, unidirectionally-stiffened structural system where the main structural elements are arranged longitudinally This technology is referred to as advanced double hull (ADH). This paper describes the second year of study in which a new design criterion was applied. This criterion was based upon the results of structural testing and analysis conducted by the Naval Surface Warfare Center Carderock Division (NSWCCD) to determine the ultimate strength of cellular structure. A full ship finite element model was developed to help validate the structural criteria. RP Sikora, J (reprint author), NAVAL SURFACE WARFARE CTR,CARDEROCK DIV,SILVER SPRING,MD, USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 117 EP 127 PG 11 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700010 ER PT J AU Fung, SC AF Fung, SC TI US high speed destroyers, 1919-1942: Hull proportions - Comment SO NAVAL ENGINEERS JOURNAL LA English DT Editorial Material RP Fung, SC (reprint author), NAVAL SURFACE WARFARE CTR,CARDEROCK DIV,SILVER SPRING,MD, USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 177 EP 178 PG 2 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700018 ER PT J AU Ricketts, JB Hundley, LL AF Ricketts, JB Hundley, LL TI Naval ship self-assessment of hull powering performance using propulsion shaft torsionmeters and GPS SO NAVAL ENGINEERS JOURNAL LA English DT Article; Proceedings Paper CT American-Society-of-Naval-Engineers Day 1997 CY MAR 18, 1997 CL WASHINGTON, DC SP Amer Soc Naval Engineers AB A prototype procedure for U.S. Navy crews to self-assess hull powering performance is being tested on selected Atlantic Fleet CG 47 class cruisers. This paper describes both the logic and methodology for ship's force to perform a self-assessment of hull power ing performance using propulsion shaft torque data obtained from installed torsionmeters, shaft speed data from ship equipment, and ship speed measurements obtained from the Global Positioning System (GPS). The prototype procedure described will provide crews with accurate knowledge of ship powering characteristics at any given time and will be minimally intrusive on ship routine. Periodic speed/power measurements will enable a ship's crew to forecast the appropriate time for hull maintenance in order to achieve the goal of minimizing fuel consumption. This will result in a reduced reliance on the subjective determination of the hull condition, and will allow the Navy to better understand hull performance trends. Technology advances have allowed this prototype hull powering assessment to be developed, and the Navy can now depart from its historically limited analysis of overall warship powering performance conducted during the life cycle of a ship. The initial clean-hull speed/power trial can today be augmented with powering data taken throughout the ship's life by the crew. This procedure will allow an accurate quantitative study of the real effects of hull and propeller fouling to be performed. C1 NAVAL SURFACE WARFARE CTR,RESISTANCE & POWERING DEPT,CARDEROCK DIV,SILVER SPRING,MD. NR 4 TC 1 Z9 1 U1 1 U2 2 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 181 EP 192 PG 12 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700020 ER PT J AU Grubb, MJ Skolnick, A AF Grubb, MJ Skolnick, A TI Operational systems, logistics engineering and technology insertion SO NAVAL ENGINEERS JOURNAL LA English DT Article; Proceedings Paper CT American-Society-of-Naval-Engineers Day 1997 CY MAR 18, 1997 CL WASHINGTON, DC SP Amer Soc Naval Engineers AB In an era of fiscal austerity, downsizing and unforgiving pressure upon human and economic capital, it is an Augean task to identify resources for fresh and creative work. The realities of the day and the practical demands of more immediate fleet needs can often dictate higher priorities. Yet, the Navy must avoid eating its seed corn. Exercising both technical insight and management foresight, the fleet, the R&D community, the Office of the Chief of Naval Operations (OpNav) and the product engineering expertise of the Naval Surface Warfare Center (NSWC) are joined and underway with integrated efforts to marry new, fully demonstrated technologies and operational urgencies. Defense funding today cannot sponsor all work that can be mission-justified over the long term because budgets are insufficient to support product maturation within the classical development cycle. However, by rigorous technical filtering and astute engineering of both marketplace capabilities and currently available components, it is possible in a few select cases to compress and, in effect, integrate advanced development (6.3), engineering development (6.4), weapon procurement (WPN), ship construction (SCN), operation and maintenance (O&M,N) budgetary categories when fleet criticalities and technology opportunities can happily meet. In short, 6.3 funds can be applied directly to ''ripe gateways'' so modern technology is inserted into existing troubled or aging systems, sidestepping the lengthy, traditional development cycle and accelerating practical payoffs to recurrent fleet problems. To produce such constructive results has required a remarkable convergence of sponsor prescience and engineering workforce excellence. The paper describes, extensively, the philosophy of approach, transition strategy, polling of fleet needs, technology assessment, and management team requirements. The process for culling and selecting specific candidate tasks for SHARP sponsorship (matching operational need with technological opportunity) is described broadly in the main body of the paper with the details provided in an Appendix. Finally, three specific examples from the methods used to pick ''best'' choices from multiple surface, air and underseas contenders are presented as illustrations of programs able to obtain recent SHARP sponsorship. RP Grubb, MJ (reprint author), NAVAL SURFACE WARFARE CTR,SHARP PROGRAM,SILVER SPRING,MD, USA. NR 2 TC 1 Z9 1 U1 1 U2 1 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 205 EP 220 PG 16 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700028 ER PT J AU Robinson, PM AF Robinson, PM TI Operational systems, logistics engineering and technology insertion - Comment SO NAVAL ENGINEERS JOURNAL LA English DT Editorial Material RP Robinson, PM (reprint author), USN,SEA SYST COMMAND,SAN DIEGO,CA, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 221 EP 222 PG 2 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700030 ER PT J AU Rivers, TM AF Rivers, TM TI Commercial lighting innovations - Comment SO NAVAL ENGINEERS JOURNAL LA English DT Editorial Material RP Rivers, TM (reprint author), USN,SEA SYST COMMAND,SAN DIEGO,CA, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 229 EP 231 PG 3 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700033 ER PT J AU Engle, A Lin, W Salvesen, N Shin, Y AF Engle, A Lin, W Salvesen, N Shin, Y TI Application of 3-D nonlinear wave-load and structural-response simulations in naval ship design SO NAVAL ENGINEERS JOURNAL LA English DT Article; Proceedings Paper CT American-Society-of-Naval-Engineers Day 1997 CY MAR 18, 1997 CL WASHINGTON, DC SP Amer Soc Naval Engineers AB Despite the limits inherent within linearized frequency-domain ship motion and wave load computer codes, strip theory has been found to provide the design community with a fairly robust, practical design tool with reasonable accuracy for most conventional displacement monohulls. However, the advent of new design concepts including multi-hulls and application of new materials as well as the push to incorporate reliability methods within surface ship structural design criteria has highlighted the need for more rigorous methods of developing a lifetime load spectrum. In this paper, a multilevel computation system for predicting ship motions and wave loads, up through and including extreme sea conditions, is presented. This system includes a traditional strip theory approach and newly developed linear and nonlinear three-dimensional time-domain methods. The new nonlinear methods are currently in the process of being validated by the U.S. Navy. The status of the current development is presented. Sample numerical results from the new nonlinear methods are compared with both linear frequency domain predictions and model tests. RP Engle, A (reprint author), USN,HYDRODYNAM LOADS TECHNOL DEV PROGRAM,SAN DIEGO,CA, USA. NR 22 TC 1 Z9 1 U1 0 U2 3 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 253 EP 266 PG 14 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700042 ER PT J AU Dalzell, JE AF Dalzell, JE TI Application of 3-D nonlinear wave-load and structural-response simulations in naval ship design - Comment SO NAVAL ENGINEERS JOURNAL LA English DT Editorial Material RP Dalzell, JE (reprint author), USN,CTR SURFACE WARFARE,CARDEROCK DIV,SILVER SPRING,MD 20903, USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 266 EP 266 PG 1 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700043 ER PT J AU Calvert, JF AF Calvert, JF TI AV-8B flight hazard awareness analysis and training using flight simulation SO NAVAL ENGINEERS JOURNAL LA English DT Article; Proceedings Paper CT American-Society-of-Naval-Engineers Day 1997 CY MAR 18, 1997 CL WASHINGTON, DC SP Amer Soc Naval Engineers AB The V/STOL capability of the AV-8B Harrier is provided through a sophisticated combination of vectored thrust and aerodynamic technology. The proper interaction of the nozzle thrust and flap system is of extreme importance. Specific combinations of nozzle angle and flap position are employed to optimize both jet lift and aerodynamic lift. However, if the proper flap-nozzle position schedule is violated, the resulting thrust and flap impingement may cause a severe nose-down pitching moment sufficient to override the pilot control. Depending upon ground proximity, this condition creates a hazard which causes great potential for loss of aircraft and/or pilot. Flap impingement hazard was identified on the AV-8B aircraft as a potential catastrophic flight hazard. In response, a requirement was established to 1) study the severity of the flap impingement hazard on the AV-8B, 2) devise flight operational procedures which would minimize pilot exposure to the hazard potential and the resulting pilot control problems during flight, and 3) devise a training capability to familiarize pilots with flap impingement hazard characteristics and recovery procedures. This paper comprises the results of a study which utilized piloted flight simulation and fleet simulation trainers to meet these requirements. RP Calvert, JF (reprint author), USN,AIR WARFARE CTR,TRAINING SYST DIV,ORLANDO,FL, USA. NR 2 TC 1 Z9 1 U1 0 U2 0 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 269 EP 276 PG 8 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700046 ER PT J AU Dirlik, S Hambric, S Azarm, S Marquardt, M Hellman, A Bartlett, S Castelli, V AF Dirlik, S Hambric, S Azarm, S Marquardt, M Hellman, A Bartlett, S Castelli, V TI Developing a prototype concurrent design tool for composite topside structures SO NAVAL ENGINEERS JOURNAL LA English DT Article; Proceedings Paper CT American-Society-of-Naval-Engineers Day 1997 CY MAR 18, 1997 CL WASHINGTON, DC SP Amer Soc Naval Engineers ID NONMONOTONE LINE SEARCH; OPTIMIZATION AB A prototype concurrent engineering tool has been developed for the preliminary design of composite topside structures for modern navy warships. This tool, named GELS for the Concurrent Engineering of Layered Structures, provides designers with an immediate assessment of the impacts of their decisions on several disciplines which are important to the performance of a modern naval topside structure, including electromagnetic interference effects (EMI), radar cross section (RCS), structural integrity, cost, and weight. Preliminary analysis modules in each of these disciplines are integrated to operate from a common set of design variables and a common materials database. Performance in each discipline and an overall fitness function for the concept are then evaluated. A graphical user interface (GUI) is used to define requirements and to display the results from the technical analysis modules. Optimization techniques, including feasible sequential quadratic programming (FSQP) and exhaustive search are used to modify the design variables to satisfy all requirements simultaneously. The development of this tool, the technical modules, and their integration are discussed noting the decisions and compromises required to develop and integrate the modules into a prototype conceptual design tool. RP Dirlik, S (reprint author), USN,CTR SURFACE WARFARE,SIGNATURES DIRECTORATE,RADAR CROSS SECT,SILVER SPRING,MD, USA. NR 18 TC 4 Z9 4 U1 0 U2 2 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 279 EP 290 PG 12 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700049 ER PT J AU Whitcomb, C AF Whitcomb, C TI Developing a prototype concurrent design tool for composite topside structures - Comment SO NAVAL ENGINEERS JOURNAL LA English DT Editorial Material RP Whitcomb, C (reprint author), USN,WASHINGTON,DC 20350, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 290 EP 290 PG 1 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700050 ER PT J AU McCarthy, PJ Munkacsy, M AF McCarthy, PJ Munkacsy, M TI The Joint Tactical Combat Training System system model SO NAVAL ENGINEERS JOURNAL LA English DT Article; Proceedings Paper CT American-Society-of-Naval-Engineers Day 1997 CY MAR 18, 1997 CL WASHINGTON, DC SP Amer Soc Naval Engineers AB The Joint Tactical Combat Training System (JTCTS) is a joint Navy/Air Force program to provide enhanced tactical combat training from single-platform warfighting through integration of multi-platform coordinated combat training (surface, subsurface, and air). Key requirements of JTCTS include the use of the Global Positioning System to generate platform position information, simulated platforms and weapons, and a real-time radio datalink to transmit training data within 400 nm of a JTCTS core-capable site, using a distributed simulation architecture derived from distributed interactive simulations. Many design tradeoffs need to be made to implement this system. To enable the meaningful test and tradeoff of various design options, a software model of the JTCTS system was constructed. This discrete-event simulation was implemented entirely in software running on commercial workstations. The model allows the designers to test various software and hardware design implementations and measure their influence on the ''goodness'' of the exercise data. Based on platform attitude and relative position, datalink connectivity can be assessed and various message-passing algorithms tested. The effects of message latency and communications dropouts on dead-reckoning accuracy can be directly measured. Effects of aircraft antenna shading, atmospheric effects on radio frequency propagation, and others can be turned on or off depending on the needs of the particular test, and to support validation of the model. The engineering model was created during the project concept definition; it is being used today in a number of design studies. One, a datalink transmitter power tradeoff, is giving insight into the relationship between the accuracy of after-action reports and the heat dissipation of the datalink components. These simulated exercises are providing both the end-user and the design team with insight into subsystem and operational interactions usually not seen until system integration testing. RP McCarthy, PJ (reprint author), USN,AIR WARFARE CTR,TRAINING SYST DIV,ORLANDO,FL, USA. NR 4 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 293 EP 298 PG 6 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700053 ER PT J AU Nickol, CL AF Nickol, CL TI Future naval aircraft and aircraft carrier design: A study of aircraft/ship interface SO NAVAL ENGINEERS JOURNAL LA English DT Article; Proceedings Paper CT American-Society-of-Naval-Engineers Day 1997 CY MAR 18, 1997 CL WASHINGTON, DC SP Amer Soc Naval Engineers AB There are two significant efforts underway which will greatly affect naval aviation. The first is the CVX study an effort to define the next class of aircraft carriers. The second is an effort to define the next class of naval aircraft, both tactical and support types. These two efforts are in the beginning stages, with projected completion dates in similar time frames; CVX construction is proposed to start in 2006, JSF IOC is in the 2008 timeframe, and the current support aircraft will require replacement starting in 2011. The purpose of this paper is to quantitatively examine the need for close coupling of the ship and aircraft design processes. First, the design space for potential aircraft is described by defining design constraints using current and past aircraft carriers as CVX surrogates. Next, the range of possible capability tradeoffs between the ship and the aircraft are examined, as the launch and recovery mechanisms are transferred from the ship to the aircraft. Quantitative examples are provided to analyze the parameters associated with the ship/aircraft interface, including both conventional catapult and arresting gear, and no catapult and arresting gear, implying a vertical or short takeoff and landing capability Finally recommendations are made for an aircraft/ship design procedure stressing a closely coupled iterative approach. RP Nickol, CL (reprint author), USN,AIR SYST COMMAND HEADQUARTERS,CONCEPTUAL DESIGN DIV,CRYSTAL CITY,VA, USA. NR 3 TC 0 Z9 0 U1 1 U2 3 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 299 EP 309 PG 11 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700054 ER PT J AU Yagla, JJ AF Yagla, JJ TI Concentric Canister Launcher SO NAVAL ENGINEERS JOURNAL LA English DT Article; Proceedings Paper CT American-Society-of-Naval-Engineers Day 1997 CY MAR 18, 1997 CL WASHINGTON, DC SP Amer Soc Naval Engineers AB The Concentric Canister Launcher (CCL) is a new concept for launching munitions from surface ships. Each concentric launcher provides a self-contained gas management system and a complete set of launcher electronics. These innovations provide the naval architect new versatility in the design of warships, significant cost and weight advantages, and improved performance when compared to existing missile launching systems. RP Yagla, JJ (reprint author), USN,CTR SURFACE WARFARE,COMBAT SYST SAFETY & ENGN DIV,DAHLGREN,VA 22448, USA. NR 25 TC 2 Z9 3 U1 0 U2 1 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 313 EP 327 PG 15 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700058 ER PT J AU Riley, MR AF Riley, MR TI Meeting the 21st century with SMART mission flexibility - Comments SO NAVAL ENGINEERS JOURNAL LA English DT Editorial Material RP Riley, MR (reprint author), USN,CTR SURFACE WARFARE,CARDEROCK DIV,SILVER SPRING,MD 20903, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 346 EP 347 PG 2 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700065 ER PT J AU Douglas, B AF Douglas, B TI Meeting the 21st century with SMART mission flexibility - Comments SO NAVAL ENGINEERS JOURNAL LA English DT Editorial Material RP Douglas, B (reprint author), USN,CTR SURFACE WARFARE,CARDEROCK DIV,SILVER SPRING,MD 20903, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 347 EP 348 PG 2 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700066 ER PT J AU Nickens, AD Pizzino, JF Crane, CH AF Nickens, AD Pizzino, JF Crane, CH TI Environmental compliance: Requirements and technology opportunities for future ships SO NAVAL ENGINEERS JOURNAL LA English DT Article; Proceedings Paper CT American-Society-of-Naval-Engineers Day 1997 CY MAR 18, 1997 CL WASHINGTON, DC SP Amer Soc Naval Engineers AB Navy ships must be able to operate anywhere in the world and visit any port unencumbered by environmental restrictions. The Office of the Chief of Naval Operations (OCNO) has formulated a vision for the environmentally sound ship of the 21st century, which will ensure compliance with environmental requirements applicable to Navy ships, while maintaining fleet effectiveness and readiness. Navy ships generate a variety of solid and liquid wastes and atmospheric emissions. Ships have limited capabilities for holding wastes for offload to shore. Working closely with the OCNO, the Naval Sea Systems Command (NavSea) is developing systems, equipment, and procedures to process and manage ship wastes in an environmentally responsible manner. Several pieces of shipboard equipment have been successfully developed to process solid and liquid waste, hazardous materials and ozone-depleting substances (ODSs). The technologies and practices being developed under this program will: ensure compliance with environmental laws and regulations, significantly reduce the logistic burdens and costs associated with shoreside offload and disposal of ship wastes, implement Navy environmental and occupational safety and health policies, enhance the quality of life aboard ship, and continue the Navy's leadership role in protecting the marine environment. RP Nickens, AD (reprint author), USN,SEA SYST COMMANDS SHIP RES DEV & STAND GRP,ENVIRONM PROTECT PROGRAM,SAN DIEGO,CA, USA. NR 12 TC 2 Z9 2 U1 0 U2 2 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 349 EP 369 PG 21 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700068 ER PT J AU Patel, A Kjos, K Sasso, F Robinson, S AF Patel, A Kjos, K Sasso, F Robinson, S TI Architecting a missile system for navy theater ballistic missile defense SO NAVAL ENGINEERS JOURNAL LA English DT Article; Proceedings Paper CT American-Society-of-Naval-Engineers Day 1997 CY MAR 18, 1997 CL WASHINGTON, DC SP Amer Soc Naval Engineers AB While most of the theater ballistic missiles (TBM) in threat countries' inventories are of the shorter range SCUD varieties, mid- to long-range versions are currently in development in a number of third world countries. Threat potential exists in the following three battle spaces: endo-atmosphere (0-30 km), high endo-atmosphere (30-70 km) and exo-atmosphere (greater than 70 km). The inherent short range and low speed of endo-atmospheric threats match well with capabilities of SM-2 Block IVA, which equips the Navy with an area defense capability The exo-atmospheric TBMs are longer range and can threaten more targets which may be widely dispersed. Their higher velocities reduce response times dramatically Therefore, exo-atmospheric TBMs create the need for Standard Missile-3 (SM-3), which provides the Navy with theater wide defense capability. Defining its area and theater wide systems as clearly endo-atmospheric and exo-atmospheric systems allows the Navy to use derivatives of the Standard Missile Block IV to take full advantage of the conditions associated with each of these operating zones. Use of an existing missile and ship system baseline also allows use of the existing interface structure to minimize cost. To counter the endo-atmospheric TBMs, the SM-2 BLK TVA upgrades include an advanced imaging infrared (IIR) seeker, an improved fast-reaction auto pilot and a forward looking RE all in the same volume as the existing missile. The highly responsive SM-2 Block IVA missile, complemented with Aegis weapons systems modifications, provides capability against enemy aircraft and cruise missiles, as well as TBMs. Standard Missile-3 (SM-3) replaces the SM-2 Block TV warhead, radar and guidance section with a boosted third stage and an advanced kinetic warhead (KW). Operation in the exo-atmospheric region permits a KW design with autonomous guidance control and divert thrusters for high maneuverability and has the capability of achieving very high interceptor velocities. RP Patel, A (reprint author), USN,PEO TAD,STAND MISSILE VERT LAUNCH SYST PROGRAM OFF,STAND MISSILE LEAP PROGRAM,WASHINGTON,DC, USA. NR 0 TC 0 Z9 1 U1 1 U2 1 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 373 EP 380 PG 8 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700071 ER PT J AU Dettbarn, JL AF Dettbarn, JL TI Joint Logistics Over The Shore operations in rough seas - Comments SO NAVAL ENGINEERS JOURNAL LA English DT Editorial Material RP Dettbarn, JL (reprint author), USN,OPERAT LOGIST,STRATEG SEALIFT PROGRAMS DIV,WASHINGTON,DC, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 393 EP 394 PG 2 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700074 ER PT J AU Fink, MD AF Fink, MD TI Joint Logistics Over The Shore operations in rough seas - Comments SO NAVAL ENGINEERS JOURNAL LA English DT Editorial Material RP Fink, MD (reprint author), USN,SEA SYST COMMAND,SAN DIEGO,CA 92152, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1997 VL 109 IS 3 BP 394 EP 395 PG 2 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA XP467 UT WOS:A1997XP46700075 ER PT J AU Coullard, CR Gardner, LL Wagner, DK AF Coullard, CR Gardner, LL Wagner, DK TI Minimum-weight cycles in 3-separable graphs SO NETWORKS LA English DT Article ID TRAVELING SALESMAN PROBLEM; PLANAR GRAPHS AB This paper presents a polynomial-time algorithm for the minimum-weight-cycle problem on graphs that decompose via 3-separations into well-structured graphs. The problem is NP-hard in general. Graphs that decompose via 3-separations into well-structured graphs include Halin, outer-facial, delta-wye, wye-delta, flat, and twirl-wheel graphs. For each of these classes of graphs, given the decomposition, the algorithm runs in linear time. (C) 1997 Jonn Wiley & Sons, Inc. C1 OFF NAVAL RES,DIV MATH COMP & INFORMAT SCI,ARLINGTON,VA 22217. NORTHWESTERN UNIV,DEPT IND ENGN & MANAGEMENT SCI,EVANSTON,IL 60208. UNIV INDIANAPOLIS,SCH BUSINESS,INDIANAPOLIS,IN 46227. NR 19 TC 0 Z9 0 U1 0 U2 0 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0028-3045 J9 NETWORKS JI Networks PD MAY PY 1997 VL 29 IS 3 BP 151 EP 160 PG 10 WC Computer Science, Hardware & Architecture; Operations Research & Management Science SC Computer Science; Operations Research & Management Science GA WU939 UT WOS:A1997WU93900003 ER PT J AU Cotell, CM Schiestel, S Carosella, CA Flom, S Hubler, GK Knies, DL AF Cotell, CM Schiestel, S Carosella, CA Flom, S Hubler, GK Knies, DL TI Ion-beam-assisted deposition of Au nanocluster/Nb2O5 thin films with nonlinear optical properties SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 10th International Conference on Ion Beam Modification of Materials (IBMM-96) CY SEP 01-06, 1996 CL ALBUQUERQUE, NM ID IMPLANTATION; SILICA AB Gold nanocluster thin films (similar to 200 nm thickness) consisting of metal clusters similar to 5 nm in size embedded in a matrix of Nb2O5 were deposited by ion beam-assisted deposition (IBAD) by coevaporation of Au and Nb with O-2(+) ion bombardment. The microstructure and optical characteristics of these films were examined as-deposited and after annealing at 600 degrees C. Annealing crystallized the amorphous oxide matrix and ripened the nanoclusters. A strong linear absorption at the wavelength of the surface plasmon resonance for Au developed as a result of annealing. The linear optical behavior was modeled using Mie scattering theory. Good agreement was found between the nanocluster sizes predicted by the theory and the particle sizes observed experimentally using transmission electron microscopy (TEM). The nonlinear optical (NLO) properties of the nanocluster films were probed experimentally using degenerate four wave mixing and nonlinear transmission. The wavelength was near the peak of the surface plasmon resonance as measured by VIS/UV spectroscopy. Values of \chi(xxxx)((3))\ were 7.3 x 10(-8) and 3.0 x 10(-10) esu for annealed and unannealed samples, respectively. The dominant mechanism for the nonlinear response was change in dielectric constant due to the generation of a distribution of hot, photoexcited electrons. RP Cotell, CM (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 12 TC 7 Z9 7 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1997 VL 127 BP 557 EP 561 DI 10.1016/S0168-583X(96)00990-1 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA XG605 UT WOS:A1997XG60500125 ER PT J AU Schiestel, S Cotell, CM Carosella, CA Grabowski, KS Hubler, GK AF Schiestel, S Cotell, CM Carosella, CA Grabowski, KS Hubler, GK TI Ion beam assisted deposition of metal nanoclusters in silica thin films SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 10th International Conference on Ion Beam Modification of Materials (IBMM-96) CY SEP 01-06, 1996 CL ALBUQUERQUE, NM ID OPTICAL-PROPERTIES; IMPLANTATION AB Gold and silver nanoclusters in silica were deposited by coevaporation of gold and silicon or silver and silicon under simultaneous oxygen bombardment. The noble metal concentration, the linear absorption coefficient and the cluster size can be controlled by variation of the process parameters. The position of the absorption peak was shifted from 400 to 700 nm by the choice of the cluster metal and the dielectric matrix. C1 UNIV HEIDELBERG,INST PHYS CHEM,D-69120 HEIDELBERG,GERMANY. RP Schiestel, S (reprint author), USN,RES LAB,CODE 6673,4555 OVERLOOK AVE,WASHINGTON,DC 20375, USA. OI Grabowski, Kenneth/0000-0003-0816-001X NR 8 TC 11 Z9 11 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1997 VL 127 BP 566 EP 569 DI 10.1016/S0168-583X(96)01126-3 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA XG605 UT WOS:A1997XG60500127 ER PT J AU Rao, MV Nordstrom, D Gardner, JA Edwards, A Roth, EG Kelner, G Ridgway, M AF Rao, MV Nordstrom, D Gardner, JA Edwards, A Roth, EG Kelner, G Ridgway, M TI Ion implantation in 6H-SiC SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 10th International Conference on Ion Beam Modification of Materials (IBMM-96) CY SEP 01-06, 1996 CL ALBUQUERQUE, NM AB In this study we have performed N, P, Al, B, V, Si, and C implantations to obtain p-type, n-type, and semi-insulating regions in 6H-SiC crystals. Post-implantation annealings were performed in either a conventional ceramic processing furnace or using microwaves in the temperature range of 1200-1700 degrees C, The material was characterized by secondary ion mass spectrometry, Hall, Rutherford backscattering via channeling, and two-probe I-V measurements. N-type regions with a maximum room temperature electron concentration of 2 x 10(19) cm(-3) were obtained using N and P implantations, Though p-type regions were obtained by Al and B, the room temperature hole concentrations were low due to the deep acceptor levels associated with these impurities. The Si and C bombardment gave regions with resistivities as high as 10(9) Omega cm compared to 1 Omega cm in the starting material. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. USN,RES LAB,WASHINGTON,DC 20375. AUSTRALIAN NATL UNIV,DEPT ELECT MAT ENGN,CANBERRA,ACT,AUSTRALIA. RP Rao, MV (reprint author), GEORGE MASON UNIV,DEPT ELECT & COMP ENGN,FAIRFAX,VA 22030, USA. RI Ridgway, Mark/D-9626-2011 OI Ridgway, Mark/0000-0002-0642-0108 NR 16 TC 9 Z9 9 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1997 VL 127 BP 655 EP 659 DI 10.1016/S0168-583X(96)01147-0 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA XG605 UT WOS:A1997XG60500149 ER PT J AU Laurent, J Wilson, G AF Laurent, J Wilson, G TI Size of cells collected from normal human subjects using contact lens cytology SO OPTOMETRY AND VISION SCIENCE LA English DT Article DE contact lens cytology; cell shedding rate; corneal epithelium; contact lenses ID SCANNING ELECTRON-MICROSCOPY; CORNEAL EPITHELIAL SURFACE; OCULAR SURFACE; WEAR; RABBIT AB This paper describes how a soft contact lens can be used to harvest cells from the surface of the corneal epithelium. The procedure is called contact lens cytology (CLC). Cells were removed from a soft contact lens by irrigation and stained with acridine orange. Two methods for the measurement of cell size are described. First, cell size was measured using a computer-assisted technique, which calculated the area of the cell from its outline. The second method was simpler in that it required only a single measurement of the longest dimension of the cell (the cell length). To test the validity of this simpler method, cell area was compared with cell length in 185 cells. The resulting correlation (r = 0.92) suggests that the size of shed cells can be described adequately using cell length in place of the more time-consuming measurement of cell area. A mathematical relation can be used to convert cell length to cell area so that results from experimenters using different measures of size can be compared. When a large pool of cells collected by CLC was divided into four aliquots and cell length measured by two observers on two different days, there were no significant differences between observers or days. Thus, the technique does not depend on one observer, and it is unaffected by a 24-h delay in measurement. Cells were harvested from the corneal epithelium of normal human subjects. The number of cells collected from any single removal of the contact lens had a range of 10 to 175 cells, and a mean of 66.8 +/- 40.4 (N = 46). Cell length was measured and plotted as frequency histograms for both eyes of each subject. The range in cell length was from 10 to 80 mu m. The mean cell length for individual subjects had a low of 26.5 +/- 9.0 pm and a high of 44.2 +/- 10.2 pm, with a grand mean for all right eyes of 36.0 +/- 5.1 pm, and a grand mean for all left eyes of 34.6 +/- 5.2 mu m. The mean for all eyes was 35.3 +/- 5.1 mu m. Composite histograms were created with the combined data from the 23 right eyes (N = 1310 cells), and the 23 left eyes (N = 1765 cells). Individual histograms and the composite histograms were not normally distributed. Peaks in the distributions suggest the presence of different subpopulations of cells, lending support to the hypothesis that there is more than one mechanism for cell shedding. C1 USN,AEROSP MED RES LAB,PENSACOLA,FL. FU NEI NIH HHS [EY03039] NR 29 TC 9 Z9 9 U1 0 U2 1 PU WILLIAMS & WILKINS PI BALTIMORE PA 351 WEST CAMDEN ST, BALTIMORE, MD 21201-2436 SN 1040-5488 J9 OPTOMETRY VISION SCI JI Optom. Vis. Sci. PD MAY PY 1997 VL 74 IS 5 BP 280 EP 287 DI 10.1097/00006324-199705000-00023 PG 8 WC Ophthalmology SC Ophthalmology GA XJ264 UT WOS:A1997XJ26400019 PM 9219286 ER PT J AU Doolan, DL Hoffman, SL AF Doolan, DL Hoffman, SL TI Multi-gene vaccination against malaria: A multistage, multi-immune response approach SO PARASITOLOGY TODAY LA English DT Review ID PLASMODIUM-FALCIPARUM SPOROZOITES; LONG-TERM PERSISTENCE; CIRCUMSPOROZOITE PROTEIN; PLASMID DNA; IMMUNIZATION; PROTECTION; EXPRESSION; ANTIBODIES; SEQUENCE; INVASION AB An ideal malaria vaccine will induce immune responses against each stage of the Plasmodium spp life cycle. During its complicated life cycle, the parasite exists extracellularly in the host's bloodstream, within cells that express major histocompatibility complex (MHC) molecules (hepatocytes), within cells that do not express MHC molecules (erythrocytes) and within the mosquito vector. Different arms of the immune system are required to attack the parasite at the different stages. Therefore, a multistage vaccine must be a multi-immune response vaccine. In addition, given the unique antigenicities of the different stages of the life cycle, implicit in this definition is that the vaccine be multivalent. Here, Denise Doolan and Stephen Hoffman present the rationale for developing a multistage, multivalent, multi-immune response malaria vaccine and explain why, among currently available technologies, DNA vaccines may offer the best prospect for success. RP Doolan, DL (reprint author), USN,MED RES INST,MALARIA PROGRAM,12300 WASHINGTON AVE,ROCKVILLE,MD 20852, USA. RI Doolan, Denise/F-1969-2015 NR 52 TC 60 Z9 63 U1 1 U2 6 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0169-4758 J9 PARASITOL TODAY JI Parasitol. Today PD MAY PY 1997 VL 13 IS 5 BP 171 EP 178 DI 10.1016/S0169-4758(97)01040-5 PG 8 WC Parasitology SC Parasitology GA WW510 UT WOS:A1997WW51000007 PM 15275087 ER PT J AU Russell, SD AF Russell, SD TI Nonreflective surface SO PHOTONICS SPECTRA LA English DT Letter RP Russell, SD (reprint author), USN,COMMAND CONTROL & OCEAN SURVEILLANCE CTR,SAN DIEGO,CA 92152, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LAURIN PUBL CO INC PI PITTSFIELD PA BERKSHIRE COMMON PO BOX 1146, PITTSFIELD, MA 01202 SN 0731-1230 J9 PHOTON SPECTRA JI Photon. Spect. PD MAY PY 1997 VL 31 IS 5 BP 94 EP 94 PG 1 WC Optics SC Optics GA WY867 UT WOS:A1997WY86700039 ER PT J AU Platt, N Hammel, SM AF Platt, N Hammel, SM TI Pattern formation in driven coupled map lattices SO PHYSICA A LA English DT Article; Proceedings Paper CT Proceedings of the International Conference on Pattern Formation in Fluids and Materials CPiP 96 (Collective Phenomena in Physics 96) CY JUN 13-15, 1996 CL UNIV WESTERN ONTARIO, LONDON, CANADA HO UNIV WESTERN ONTARIO ID ON-OFF INTERMITTENCY; SPATIOTEMPORAL CHAOS; TURBULENCE; ATTRACTORS; TRANSITION; DYNAMICS; SYSTEMS; NOISE AB We use a coupled map lattice as a model for convected temperature fluctuations in the atmosphere above an ocean surface. We introduce a simple model for spatio-temporal bursting in a two-dimensional coupled map lattice. Diffusion is controlled by the strength of the nearest-neighbor coupling of the lattice elements. This diffusion is modified to take into account spatially preferential directions. and this spatial preference is used to capture possible buoyancy effects. As diffusion and buoyancy are varied. convective spatio-temporal patterns are observed in the lattice. C1 USN,CTR SURFACE WARFARE,NONLINEAR DYNAM & WAVELETS GRP,DAHLGREN,VA 22448. NR 24 TC 10 Z9 11 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4371 J9 PHYSICA A JI Physica A PD MAY 1 PY 1997 VL 239 IS 1-3 BP 296 EP 303 DI 10.1016/S0378-4371(97)00488-3 PG 8 WC Physics, Multidisciplinary SC Physics GA XE559 UT WOS:A1997XE55900032 ER PT J AU Bacalis, NC Theodorakopoulos, N Papaconstantopoulos, DA AF Bacalis, NC Theodorakopoulos, N Papaconstantopoulos, DA TI Wave-vector-dependent Stoner approach to band ferromagnetism in Ni SO PHYSICAL REVIEW B LA English DT Article ID TRANSITION-METALS; MAGNETISM; NICKEL; IRON AB Recent experimental evidence [W. von der Linden et al., Phys. Rev. Lett. 71, 899 (1993)] that the exchange splitting in Ni follows the temperature dependence of the magnetization and provides strong support for the physical basis of the Stoner model of itinerant ferromagnetism. In this work, augmented plane wave results for paramagnetic and spin-polarized bands (supplemented by a single-parameter shrinking of the band splitting to fit the experimental value available at the symmetry point L-3) are used in a k-dependent, Stoner-like calculation, of the Curie temperature of Ni. The calculated magnetization curve, saturation magnetization, Curie temperature, and specific heat coefficient are in agreement with experiment. C1 USN, RES LAB, COMPLEX SYST THEORY BRANCH, WASHINGTON, DC 20375 USA. RP NATL HELLEN RES FDN, INST THEORET & PHYS CHEM, 48 VAS CONSTANTINOU AVE, GR-11635 ATHENS, GREECE. RI Bacalis, Naoum/G-5327-2013; Theodorakopoulos, Nikos/L-8490-2013 OI Bacalis, Naoum/0000-0002-9565-0414; Theodorakopoulos, Nikos/0000-0003-2654-1625 NR 25 TC 5 Z9 5 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1997 VL 55 IS 17 BP 11391 EP 11394 DI 10.1103/PhysRevB.55.11391 PG 4 WC Physics, Condensed Matter SC Physics GA WY504 UT WOS:A1997WY50400068 ER PT J AU Gluckman, BJ Spano, ML Yang, WM Ding, MZ In, V Ditto, WL AF Gluckman, BJ Spano, ML Yang, WM Ding, MZ In, V Ditto, WL TI Tracking unstable periodic orbits in nonstationary high-dimensional chaotic systems: Method and experiment SO PHYSICAL REVIEW E LA English DT Article ID STEADY-STATES; TIME-SERIES; STABILIZATION; RIBBON; LASER AB We consider the adaptive control of chaos in nonstationary high-dimensional dynamical systems. In particular, we propose and experimentally implement a technique to stabilize and track unstable periodic orbits based on the use of time series. In our technique, the position of the periodic orbit and other parameters in the controller are continually updated from recent measurements of the system state and perturbation histories, while the environment, simulated by one or several of the system's parameters, drifts independent of the control algorithm. We demonstrate the effectiveness of the technique computationally for the Henon map, a chemical reaction model, and a coupled driven Duffing oscillator, and experimentally for a magnetoelastic ribbon system. C1 USN,CTR SURFACE WARFARE,WHITE OAK LAB,SILVER SPRING,MD 20903. FLORIDA ATLANTIC UNIV,CTR COMPLEX SYST,PROGRAM BRAIN SCI,BOCA RATON,FL 33431. FLORIDA ATLANTIC UNIV,DEPT MATH SCI,BOCA RATON,FL 33431. GEORGIA INST TECHNOL,SCH PHYS,ATLANTA,GA 30332. RI Spano, Mark/B-6883-2011; OI Ditto, William/0000-0002-7416-8012 NR 33 TC 17 Z9 18 U1 0 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1997 VL 55 IS 5 BP 4935 EP 4942 DI 10.1103/PhysRevE.55.4935 PN A PG 8 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA XB191 UT WOS:A1997XB19100020 ER PT J AU So, P Ott, E Sauer, T Gluckman, BJ Grebogi, C Schiff, SJ AF So, P Ott, E Sauer, T Gluckman, BJ Grebogi, C Schiff, SJ TI Extracting unstable periodic orbits from chaotic time series data SO PHYSICAL REVIEW E LA English DT Article ID STRANGE SETS; ATTRACTORS; SYSTEMS AB A general nonlinear method to extract unstable periodic orbits from chaotic time series is proposed. By utilizing the estimated local dynamics along a trajectory, we devise a transformation of the time series data such that the transformed data are concentrated on the periodic orbits. Thus, one can extract unstable periodic orbits from a chaotic time series by simply looking for peaks in a finite grid approximation of the distribution function of the transformed data. Our method is demonstrated using data from both numerical and experimental examples, including neuronal ensemble data from mammalian brain slices. The statistical significance of the results in the presence of noise is assessed using surrogate data. C1 GEORGE WASHINGTON UNIV,WASHINGTON,DC 20010. UNIV MARYLAND,INST PLASMA RES,COLLEGE PK,MD 20742. GEORGE MASON UNIV,DEPT MATH,FAIRFAX,VA 22030. USN,CTR SURFACE WARFARE,CARDEROCK DIV,BETHESDA,MD 20054. UNIV MARYLAND,DEPT PHYS & ELECT ENGN,COLLEGE PK,MD 20742. UNIV MARYLAND,SYST RES INST,COLLEGE PK,MD 20742. UNIV MARYLAND,DEPT MATH,COLLEGE PK,MD 20742. UNIV MARYLAND,INST PHYS SCI & TECHNOL,COLLEGE PK,MD 20742. RP So, P (reprint author), CHILDRENS NATL MED CTR,CHILDRENS RES INST,CTR NEUROSCI,WASHINGTON,DC 20010, USA. RI Sauer, Timothy/H-8272-2012; O, E/F-1630-2015 OI Sauer, Timothy/0000-0002-8501-8722; NR 40 TC 103 Z9 110 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1997 VL 55 IS 5 BP 5398 EP 5417 DI 10.1103/PhysRevE.55.5398 PN A PG 20 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA XB191 UT WOS:A1997XB19100070 ER PT J AU Hafizi, B Ting, A Esarey, E Sprangle, P Krall, J AF Hafizi, B Ting, A Esarey, E Sprangle, P Krall, J TI Vacuum beat wave acceleration SO PHYSICAL REVIEW E LA English DT Article ID ELECTRON ACCELERATION; LASER-PULSES; PLASMA-WAVE AB A vacuum beat wave accelerator (VBWA), in which two focused laser beams of differing wavelengths generate a beat wave that can impart a net acceleration to particles, is analyzed and simulated, The mechanism relies on the ponderomotive (vXB) force, thus circumventing the so-called Lawson-Woodward theorem. No gas, plasma, or other proximate material medium is required to achieve a net energy gain, The single-stage energy gain of the VBWA is limited by diffraction of the laser beams, particle slippage, and radial walkoff. In the simulations the particles are synchronous with the brat wave for a short interval of time and the energy gain has the nature of an impulse delivered near the focal region. Simulations show that the problem of radial walkoff may be ameliorated by using a converging beam of particles, as naturally occurs for injection of a finite-emittance beam. For terawatt-level laser beams, with wavelengths 1 mu m and 0.5 mu m, and a 4.5 MeV finite-emittance electron beam, the energy can be increased to similar to 12.5 MeV in a nonsynchronous interaction over a distance of under 4 mm, with a peak acceleration gradient similar to 15 GeV/m and an estimated trapping fraction of similar to 1%. The simulated energy gain is compared with analytical predictions. Scaling is illustrated by increasing the injection energy to 50 MeV. C1 OMEGA P INC,NEW HAVEN,CT 06520. USN,RES LAB,DIV PLASMA PHYS,WASHINGTON,DC 20375. RP Hafizi, B (reprint author), ICARUS RES INC,POB 30708,BETHESDA,MD 20824, USA. NR 26 TC 60 Z9 60 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1997 VL 55 IS 5 BP 5924 EP 5933 DI 10.1103/PhysRevE.55.5924 PN B PG 10 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA XB192 UT WOS:A1997XB19200032 ER PT J AU Sprangle, P Hafizi, B Hubbard, RF AF Sprangle, P Hafizi, B Hubbard, RF TI Ionization and pulse lethargy effects in inverse Cherenkov accelerators SO PHYSICAL REVIEW E LA English DT Article ID LASER ACCELERATION; ELECTRONS; BEAM AB Ionization processes limit the accelerating gradient and place an upper limit on the pulse duration of the electromagnetic driver in the inverse Cherenkov accelerator (ICA). Group velocity slippage, i.e., pulse lethargy, on the other hand, imposes a lower limit on the pulse duration. These limits are obtained for two ICA configurations in which the electromagnetic driver (e.g., laser or millimeter wave source) is propagated in a waveguide that is (i) lined with a dielectric material or (ii) filled with a neutral gas. In either configuration the electromagnetic driving field is guided and has an axial electric field with phase velocity equal to the speed of light in vacuum, c. The intensity of the driver in the ICA, and therefore the acceleration gradient, is limited by tunneling and collisional ionization effects, Partial ionization of the dielectric liner or gas can lead to significant modification of the dispersive properties of the waveguide, altering the phase velocity of the accelerating field and causing particle slippage, thus disrupting the acceleration process. An additional limitation on the pulse duration is imposed since the group velocity of the driving pulse is less than c and the pulse slips behind the accelerated electrons. Hence for sufficiently short pulses the electrons outrun the pulse, terminating the acceleration. Limitations on the driver pulse duration and accelerating gradient, due to ionization and pulse lethargy, are estimated for the two ICA configurations. Maximum accelerating gradients and pulse durations are presented for a 10 mu m, 1 mm, and 1 cm wavelength electromagnetic driver. The combination of ionization and pulse lethargy effects impose severe limitations on the maximum energy gain in inverse Cherenkov accelerators. C1 ICARUS RES INC,BETHESDA,MD 20824. RP Sprangle, P (reprint author), USN,RES LAB,DIV PLASMA PHYS,BEAM PHYS BRANCH,WASHINGTON,DC 20375, USA. NR 30 TC 10 Z9 10 U1 1 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1997 VL 55 IS 5 BP 5964 EP 5975 DI 10.1103/PhysRevE.55.5964 PN B PG 12 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA XB192 UT WOS:A1997XB19200035 ER PT J AU Pogozelski, EM Katz, J Huang, TT AF Pogozelski, EM Katz, J Huang, TT TI The flow structure around a surface piercing strut SO PHYSICS OF FLUIDS LA English DT Article ID 0.6 SHIP MODEL; BOUNDARY-LAYER; BREAKING WAVE; VISUALIZATION; TOPOLOGY; FIELD; WAKE AB The flow near a surface piercing, symmetric body with a long draft is examined. The experiments are performed in a towing tank at 0.05 less than or equal to Fr-L less than or equal to 0.51, primarily focusing on Fr-L=0.25, and include velocity measurements using PIV as well as video and film photography above and below the free surface. The bow wave is mild (no bubble entrainment) for Froude numbers below 0.35; however, bow wave breaking and vorticity entrainment at the toe of the wave occur. Energy dissipation in the bow wave is significant and affects the flow behind it. At Fr-L greater than or equal to 0.15, impingement of the flow on the model near x/L=0.41 generates a turbulent, bubbly wake. On the mid-body just behind this impingement is the origin of a second wave, containing several regions of counter-rotating vorticity which entrain bubbles from the free surface. The wave crest becomes milder and eventually irrotational with increasing distance from the model. At x/L=0.64, boundary layer separation begins at the intersection of the model and the free surface. The separated region sows, but never extends far from the free surface. The separation process originates from secondary flows associated with impingement and breaking at the root of the mid-body wave. At Fr-L=0.25, there is no reverse flow within the separated region, but at Fr-L>0.30, flow reversal does occur. (C) 1997 American Institute of Physics. C1 USN,CTR SURFACE WARFARE,CARDEROCK DIV,BETHESDA,MD 20084. RP Pogozelski, EM (reprint author), JOHNS HOPKINS UNIV,DEPT MECH ENGN,BALTIMORE,MD 21218, USA. RI Katz, Joseph/A-7624-2010 OI Katz, Joseph/0000-0001-9067-2473 NR 24 TC 10 Z9 10 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-6631 J9 PHYS FLUIDS JI Phys. Fluids PD MAY PY 1997 VL 9 IS 5 BP 1387 EP 1399 DI 10.1063/1.869267 PG 13 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA WW801 UT WOS:A1997WW80100023 ER PT J AU Dahlburg, RB Boncinelli, P Einaudi, G AF Dahlburg, RB Boncinelli, P Einaudi, G TI The evolution of plane current-vortex sheets SO PHYSICS OF PLASMAS LA English DT Article ID RESISTIVE TEARING INSTABILITY; EQUILIBRIUM SHEAR-FLOW; SECONDARY INSTABILITY; SOLAR SURGES; TURBULENCE; VISCOSITY; MODE; RECONNECTION; MECHANISM; PLASMA AB The linear and nonlinear evolution of the plane current-vortex sheet, with a basic magnetic field given by B-0(y)= tanh y (e) over cap(z) and a basic velocity field given by W-0(y)= V tanh Ry (e) over cap(z), is examined. The discovery of an ideal instability in a large region of parameter space previously found to be stable is reported. In this paper numerical evidence is presented that this parameter regime is in fact highly unstable, with growth rates exceeding those of the modes existing in the region of parameter space previously found to be unstable. An examination of the perturbation energy balance indicates that enhanced energy transfer from the basic velocity field to the perturbed velocity and magnetic fields is responsible for the enhanced growth rate. This occurs due to processes absent from both the resistive and Kelvin-Helmholtz instabilities. Nonlinearly it is found that magnetic reconnection can occur on an ideal time scale in certain cases. These faster instabilities lead to a more violent cascade of excitation in the streamwise direction, as evidenced by the rapid formation of higher harmonics of the initial disturbance. A nonlinear saturation due to increased correlation of the perturbed velocity and magnetic field occurs for all cases. (C) 1997 American Institute of Physics. C1 UNIV FLORENCE,DIPARTIMENTO ENERGET SERGIO STECCO,I-50100 FLORENCE,ITALY. UNIV PISA,DIPARTIMENTO FIS,I-56100 PISA,ITALY. RP Dahlburg, RB (reprint author), USN,RES LAB,COMPUTAT PHYS & FLUID DYNAM LAB,WASHINGTON,DC 20375, USA. RI Boncinelli, Paolo/C-2192-2013 NR 33 TC 31 Z9 31 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1997 VL 4 IS 5 BP 1213 EP 1226 DI 10.1063/1.872301 PN 1 PG 14 WC Physics, Fluids & Plasmas SC Physics GA WY646 UT WOS:A1997WY64600005 ER PT J AU Brown, C Seely, J Feldman, U Obenschain, S Bodner, S Pawley, C Gerber, K Sethian, J Mostovych, A Aglitskiy, Y Lehecka, T Holland, G AF Brown, C Seely, J Feldman, U Obenschain, S Bodner, S Pawley, C Gerber, K Sethian, J Mostovych, A Aglitskiy, Y Lehecka, T Holland, G TI High-resolution x-ray imaging of planar foils irradiated by the Nike KrF laser SO PHYSICS OF PLASMAS LA English DT Article ID INCOHERENCE AB Thin plastic (CH) foils were irradiated by the Naval Research Laboratory Nike [Obenschain et al., Phys. Plasmas 3, 2098 (1996)] KrF laser and were imaged in the x-ray and extreme ultraviolet regions with two-dimensional spatial resolution in the 3-10 mu m range. The CH foils were backlit by a silicon plasma. A spherically curved quartz crystal produced monochromatic images of the Si+12 resonance line radiation with energy 1865 eV that was transmitted by the CK foils. Instabilities that were seeded by linear ripple patterns on the irradiated sides of CH foils were observed. The ripple patterns had periods in the 31-125 mu m range and amplitudes in the 0.25-5.0 mu m range. The silicon backlighter emission was recorded by an x-ray spectrometer, and the 1865 eV resonance line emission was recorded by a fast x-ray diode. The multilayer mirror telescope recorded images of the C+3 1550 Angstrom emission (energy 8.0 eV) from the backside of the CK foils. (C) 1997 American Institute of Physics. C1 SCI APPLICAT INT CORP,MCLEAN,VA 22102. SFA INC,LANDOVER,MD 20785. RP Brown, C (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 7 TC 12 Z9 12 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1997 VL 4 IS 5 BP 1397 EP 1401 DI 10.1063/1.872315 PN 1 PG 5 WC Physics, Fluids & Plasmas SC Physics GA WY646 UT WOS:A1997WY64600023 ER PT J AU Vlasov, AN Nusinovich, GS Levush, B AF Vlasov, AN Nusinovich, GS Levush, B TI Effect of the zero spatial harmonic in a slow electromagnetic wave on operation of relativistic backward-wave oscillators SO PHYSICS OF PLASMAS LA English DT Article AB A linear theory of resonant backward-wave oscillators (BWOs) that takes into account the zero spatial harmonic is developed. It is shown that, depending on the phase shift, this harmonic can either increase or decrease the starting current of the device. The nonlinear theory shows the some effect of the phase shift on the maximum efficiency of the BWO. The numerical analysis of nonstationary processes has also demonstrated the effect of the phase shift on the range of beam current values in which the BWO operates in a steady-state single-frequency regime. The effect of boundary conditions at the cathode end of the slow-wave structure on the phase shift between harmonics is also analyzed. (C) 1997 American Institute of Physics. C1 USN,RES LAB,WASHINGTON,DC 20375. MOSCOW MV LOMONOSOV STATE UNIV,DEPT PHYS,MOSCOW 119899,RUSSIA. RP Vlasov, AN (reprint author), UNIV MARYLAND,INST PLASMA RES,COLLEGE PK,MD 20742, USA. NR 18 TC 14 Z9 16 U1 1 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1997 VL 4 IS 5 BP 1402 EP 1412 DI 10.1063/1.872316 PN 1 PG 11 WC Physics, Fluids & Plasmas SC Physics GA WY646 UT WOS:A1997WY64600024 ER PT J AU Ganguli, G AF Ganguli, G TI Stability of an inhomogeneous transverse plasma flow SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 38th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 11-15, 1996 CL DENVER, CO SP Amer Phys Soc, Div Plasma Phys ID ION-CYCLOTRON INSTABILITY; VELOCITY-SHEAR; ELECTRIC-FIELD; ELECTROSTATIC-WAVES; MAGNETIC-FIELD; TURBULENCE; DRIVEN; SIMULATION; BOUNDARY; DENSITY AB The stability of a magnetized plasma that includes a sheared transverse flow is analyzed by using both fluid and kinetic formalisms. In addition to the well known Kelvin-Helmholtz modes it is found that another branch of oscillation exists which can dominate the collective effects in a plasma if the magnitude of shear in the transverse flow is sufficiently strong. The source of free energy for the new branch is an inhomogeneity in the energy density caused by the velocity shear. Kelvin-Helmholtz modes, when examined with a fluid theory, are found to be robust and therefore have dominated the analysis of plasma systems with velocity shear in both laboratory and space plasmas. However, when a kinetic formalism is applied to Kelvin-Helmholtz modes it is found that these modes an strongly Landau damped especially when the ion temperature is comparable to or larger than the electron temperature. In addition, since the Kelvin-Helmholtz mode is dependent explicitly on the second derivative of the flow it is sensitive to the profile of the flow. On the Ether hand, the new branch is dependent on the localized nature of the flow and hence it is less sensitive to the details of the flow profile. The two branches of oscillation an compared using both fluid and kinetic theories and their regimes of dominance discussed. RP Ganguli, G (reprint author), USN,RES LAB,DIV PLASMA PHYS,CODE 6794,WASHINGTON,DC 20375, USA. NR 37 TC 33 Z9 35 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1997 VL 4 IS 5 BP 1544 EP 1551 DI 10.1063/1.872285 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA WY647 UT WOS:A1997WY64700005 ER PT J AU Ting, A Moore, CI Krushelnick, K Manka, C Esarey, E Sprangle, P Hubbard, R Burris, HR Fischer, R Baine, M AF Ting, A Moore, CI Krushelnick, K Manka, C Esarey, E Sprangle, P Hubbard, R Burris, HR Fischer, R Baine, M TI Plasma wakefield generation and electron acceleration in a self-modulated laser wakefield accelerator experiment SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 38th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 11-15, 1996 CL DENVER, CO SP Amer Phys Soc, Div Plasma Phys ID STIMULATED RAMAN BACKWARD; BEAT-WAVE EXPERIMENTS; 2ND-HARMONIC EMISSION; UNDERDENSE PLASMAS; THOMSON SCATTERING; TERAWATT LASER; INTENSE; PULSES; PROPAGATION; INSTABILITY AB A self-modulated laser wakefield accelerator (SM-LWFA) experiment was performed at the Naval Research Laboratory. Large amplitude plasma wakefields produced by a sub-picosecond, high intensity laser pulse (7 x 10(18) W/cm(2)) in an underdense plasma (n(e) approximate to 10(19) cm(-3)) were measured with a pump-probe coherent Thomson scattering (CTS) technique to last for less than 5 ps, consistent with the decay of large amplitude plasma waves due to the modulational instability. A plasma channel was observed to form in the wake of the pump laser pulse, and its evolution was measured with the pump-probe CTS diagnostic. The trailing probe laser pulse was observed to be guided by this channel for about 20 Rayleigh lengths. High energy electrons (up to 30 MeV) have been measured using an electro-magnetic spectrometer, with the energy spectra and divergence of lower energy (up to 4 MeV) electrons obtained using photographic films. Highly nonlinear plasma waves were also detected using forward Raman scattering diagnostics and were observed to correlate with the electron signals. Simulations of self-trapping of plasma electrons from the interaction of the laser wakefield with the slow plasma wave generated by Raman backscattering are also presented. (C) 1997 American Institute of Physics. RP Ting, A (reprint author), USN,RES LAB,DIV PLASMA PHYS,WASHINGTON,DC 20375, USA. NR 60 TC 159 Z9 160 U1 2 U2 17 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1997 VL 4 IS 5 BP 1889 EP 1899 DI 10.1063/1.872332 PN 2 PG 11 WC Physics, Fluids & Plasmas SC Physics GA WY647 UT WOS:A1997WY64700047 ER PT J AU Gold, SH Fliflet, AW Kinkead, AK Hafizi, B Nezhevenko, OA Yakovlev, VP Hirshfield, JL True, R AF Gold, SH Fliflet, AW Kinkead, AK Hafizi, B Nezhevenko, OA Yakovlev, VP Hirshfield, JL True, R TI X-band magnicon amplifier for the next linear collider SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 38th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 11-15, 1996 CL DENVER, CO SP Amer Phys Soc, Div Plasma Phys ID OUTPUT CAVITY; DESIGN AB The magnicon is a scanning-beam microwave amplifier that is being developed as a high power, highly efficient microwave source for use in powering the next generation of high gradient electron linear accelerators. This article first discusses the results from a cold cathode magnicon experiment at 11.12 GHz, driven by a single-shot Marx generator, Following this, a design is presented for a new thermionic magnicon experiment to produce more than 50 MW at 11.4 GHz, using a 210 A, 500 kV beam from an ultrahigh convergence thermionic electron gun driven by a repetition-rated modulator. This new design has a predicted efficiency in excess of 60%. (C) 1997 American Institute of Physics. C1 SACHS FREEMAN ASSOCIATES INC,LANDOVER,MD 20785. ICARUS RES INC,BETHESDA,MD 20824. OMEGA P INC,NEW HAVEN,CT 06520. LITTON SYST INC,DIV ELECTRON DEVICES,SAN CARLOS,CA 94070. BUDKER INST NUCL PHYS,NOVOSIBIRSK 630090,RUSSIA. RP Gold, SH (reprint author), USN,RES LAB,DIV PLASMA PHYS,BEAM PHYS BRANCH,WASHINGTON,DC 20375, USA. NR 20 TC 11 Z9 11 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1997 VL 4 IS 5 BP 1900 EP 1906 DI 10.1063/1.872333 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA WY647 UT WOS:A1997WY64700048 ER PT J AU Pawley, CJ Gerber, K Lehmberg, RH McLean, EA Mostovych, AN Obenschain, SP Sethian, JD Serlin, V Stamper, JA Sullivan, CA Bodner, SE Colombant, D Dahlburg, JP Schmitt, AJ Gardner, JH Brown, C Seely, JF Lehecka, T Aglitskiy, Y Deniz, AV Chan, Y Metzler, N Klapisch, M AF Pawley, CJ Gerber, K Lehmberg, RH McLean, EA Mostovych, AN Obenschain, SP Sethian, JD Serlin, V Stamper, JA Sullivan, CA Bodner, SE Colombant, D Dahlburg, JP Schmitt, AJ Gardner, JH Brown, C Seely, JF Lehecka, T Aglitskiy, Y Deniz, AV Chan, Y Metzler, N Klapisch, M TI Measurements of laser-imprinted perturbations and Rayleigh-Taylor growth with the Nike KrF laser SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 38th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 11-15, 1996 CL DENVER, CO SP Amer Phys Soc, Div Plasma Phys ID INDUCED SPATIAL INCOHERENCE; SCALE-LENGTH PLASMAS; SMOOTHING TECHNIQUES; TARGETS; BEAM; FUSION; SCATTERING; ABLATION; MATTER; LIGHT AB Nike is a 56 beam Krypton Fluoride (KrF) laser system using Induced Spatial Incoherence (ISI) beam smoothing with a measured focal nonuniformity [Delta I/I] of 1% rms in a single beam [S. Obenschain et al., Phys. Plasmas 3, 1996 (2098)]. When 37 of these beams are overlapped on the target, we estimate that the beam nonuniformity is reduced by root 37, to (Delta I/I)congruent to 0.15% (excluding short-wavelength beam-to-beam interference). The extraordinary uniformity of the laser drive, along with a newly developed x-ray framing diagnostic, has provided a unique facility for the accurate measurements of Raylejgh-Taylor amplified laser-imprinted mass perturbations under conditions relevant to direct-drive laser fusion. Data from targets with smooth surfaces as well as those with impressed sine wave perturbations agree with our two-dimensional (2-D) radiation hydrodynamics code that includes the time-dependent ISI beam modulations. A 2-D simulation of a target with a 100 Angstrom rms randomly rough surface finish driven by a completely uniform beam gives final perturbation amplitudes similar to the experimental data for the smoothest laser profile. These results are promising for direct-drive laser fusion. C1 USN,RES LAB,LAB COMPUTAT PHYS,WASHINGTON,DC 20375. USN,RES LAB,DIV SPACE SCI,WASHINGTON,DC 20375. SCI APPLICAT INT CORP,MCLEAN,VA 22310. ARTEP INC,COLUMBIA,MD 21045. RP Pawley, CJ (reprint author), USN,RES LAB,DIV PLASMA PHYS,CODE 6730,WASHINGTON,DC 20375, USA. NR 31 TC 65 Z9 68 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1997 VL 4 IS 5 BP 1969 EP 1977 DI 10.1063/1.872560 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA WY647 UT WOS:A1997WY64700057 ER PT J AU Kostoff, RN AF Kostoff, RN TI Identifying research program technical risk SO RESEARCH-TECHNOLOGY MANAGEMENT LA English DT Editorial Material RP Kostoff, RN (reprint author), USN, OFF NAVAL RES, LAB INDEPENDENT RES PROGRAM, ARLINGTON, VA 22203 USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU INDUSTRIAL RESEARCH INST, INC PI ARLINGTON PA 2200 CLARENDON BLVD, STE 1102, ARLINGTON, VA 22201 USA SN 0895-6308 J9 RES TECHNOL MANAGE JI Res.-Technol. Manage. PD MAY-JUN PY 1997 VL 40 IS 3 BP 10 EP 12 PG 3 WC Business; Engineering, Industrial; Management SC Business & Economics; Engineering GA WW974 UT WOS:A1997WW97400005 ER PT J AU Harris, VG Elam, WT AF Harris, VG Elam, WT TI A miniature total-electron-yield detector for the measurement of x-ray absorption spectra SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID FINE-STRUCTURE AB We have designed, built, and tested a total-electron-yield detector for the collection of x-ray absorption spectra. The virtues of this detector are its compact size and simplicity of design, fabrication. assembly, and use. Sample exchange and realignment with respect to the incident beam are easily performed. The design and performance of this detector are presented and discussed in comparison with other detection schemes. RP Harris, VG (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. RI Harris, Vincent/A-8337-2009 NR 7 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAY PY 1997 VL 68 IS 5 BP 1972 EP 1974 DI 10.1063/1.1148084 PG 3 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA WZ517 UT WOS:A1997WZ51700007 ER PT J AU Ngai, KL Plazek, DJ Rendell, RW AF Ngai, KL Plazek, DJ Rendell, RW TI Some examples of possible descriptions of dynamic properties of polymers by means of the coupling model SO RHEOLOGICA ACTA LA English DT Article DE polymer viscoelasticity; thermal rheological complexity; the coupling model; the terminal zone ID TIME-TEMPERATURE SUPERPOSITION; ELASTIC NEUTRON-SCATTERING; LINEAR AMORPHOUS POLYMERS; VISCOELASTIC PROPERTIES; DIELECTRIC-SPECTROSCOPY; MOLECULAR-DYNAMICS; CIS-POLYISOPRENE; THERMORHEOLOGICAL COMPLEXITY; HYDROGENATED POLYBUTADIENE; POLY(PROPYLENE GLYCOL) AB Thanks to the research efforts of Prof. John D. Ferry and others over the last several decades, the viscoelastic properties of polymers have been extensively determined. From this accumulated wisdom, polymer viscoelasticity has become a mature field of research. This basic knowledge of polymer viscoelasticity has made it possible to discern the deviations from the apparently established general rules that one of us (DJP) have found, continuing the tradition of exhaustive experimental measurement started by Prof. Ferry. From many experimental studies on polymers carried out in different laboratories, it has also become clear that these viscoelastic anomalies are general and not exceptional features. Therefore, they pose significant problems in the quest of a truly satisfactory understanding of polymer viscoelasticity. The Coupling Model (CM) has been used to rationalize a number of deviations from thermorheological simplicity. In the realm of polymer viscoelastic behavior, we consider first the local segmental motion that is responsible for the glass temperature and show that the CM provides a consistent description in either the modulus or the compliance representation. Next, we elucidate several viscoelastic anomalies which originate from the different viscoelastic mechanisms being thermorheologically complex. Finally, we revisit the original formulation of the terminal relaxation of entangled polymer chains using the CM. The neglect of the lateral nature of the constraints imposed on one chain by other chains in the original formulation leads to failure in explaining the shape of the terminal relaxation, although it is successful in other aspects. A new formulation, which includes the lateral nature of the constraints and its subsequent mitigation when the terminal relaxation is reached, has restored consistency of the prediction with the terminal relaxation of a monodisperse polyisoprene melt probed dielectrically. The results can describe also the experimental data of dilute poly isoprene probes in polybutadiene matrices and in networks. C1 UNIV PITTSBURGH, DEPT MAT SCI & ENGN, PITTSBURGH, PA 15361 USA. RP USN, RES LAB, CODE 6807, WASHINGTON, DC 20375 USA. NR 96 TC 71 Z9 71 U1 2 U2 10 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0035-4511 EI 1435-1528 J9 RHEOL ACTA JI Rheol. Acta PD MAY-JUN PY 1997 VL 36 IS 3 BP 307 EP 319 PG 13 WC Mechanics SC Mechanics GA XL286 UT WOS:A1997XL28600013 ER PT J AU Choi, IS Roland, CM AF Choi, IS Roland, CM TI Strain-crystallization of guayule and hevea rubbers SO RUBBER CHEMISTRY AND TECHNOLOGY LA English DT Article ID NATURAL-RUBBER; ORIENTATIONAL CRYSTALLIZATION; SYNTHETIC ANALOGS; CIS-POLYISOPRENE; NETWORKS; POLY(ETHYLENE-TEREPHTHALATE); FIBERS; TRANSITIONS; MORPHOLOGY; ELASTICITY AB A comparison was made of the room temperature strain-crystailization of naturally-occurring cis-1,4-polyisoprenes having varying non-rubber content. A variety of measurements were employed to assess crystallization, including stress relaxation, optical birefringence, and the infrared absorption spectrum. All methods yielded the same result: The strain required to induce crystallization is less for polyisoprenes having larger concentrations of impurities. The ability to crystallize at lower orientation presumably underlies the superior failure properties of guayule rubber and the poorer grades of natural rubber (NR) in comparison to deproteinized NR. C1 SACHS FREEMAN ASSOCIATES INC,LANDOVER,MD 20785. USN,RES LAB,DIV CHEM,WASHINGTON,DC 20375. NR 61 TC 27 Z9 28 U1 1 U2 10 PU AMER CHEMICAL SOC INC PI AKRON PA RUBBER DIV UNIV AKRON PO BOX 499, AKRON, OH 44309-0499 SN 0035-9475 J9 RUBBER CHEM TECHNOL JI Rubber Chem. Technol. PD MAY-JUN PY 1997 VL 70 IS 2 BP 202 EP 210 DI 10.5254/1.3538425 PG 9 WC Polymer Science SC Polymer Science GA XU414 UT WOS:A1997XU41400005 ER PT J AU McCoy, PA AF McCoy, PA TI A classical theorem on the singularities of Legendre series in C-3 and associated system of hyperbolic partial differential equations SO SIAM JOURNAL ON MATHEMATICAL ANALYSIS LA English DT Article DE Legendre series; singularities; function-theoretic methods AB A classical theorem of Nehari relates the singularities of Legendre series expansions in C-z with those of associated Taylor's series in C-t. The generalization of Nehari's theorem is known for Legendre series in C-z1 x z2. In this paper, function theoretic methods develop the analogous relationships between the singularities of series expanded as triple products of Legendre polynomials in C-z1 x z2 x z3 and those of associated analytic functions in C-t. The singularities of these generalized Legendre series are determined by certain elliptic curves. Moreover, these series satisfy a system of hyperbolic partial differential equations (PDEs) in C-3 that are connected to Bochner's study of Poisson processes in R-2. RP McCoy, PA (reprint author), USN ACAD,DEPT MATH,ANNAPOLIS,MD 21402, USA. NR 17 TC 0 Z9 0 U1 0 U2 0 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 SN 0036-1410 J9 SIAM J MATH ANAL JI SIAM J. Math. Anal. PD MAY PY 1997 VL 28 IS 3 BP 704 EP 714 DI 10.1137/S0036141094273490 PG 11 WC Mathematics, Applied SC Mathematics GA WW983 UT WOS:A1997WW98300011 ER PT J AU Blood, C AF Blood, C TI Casualty sustainment - Response SO SIMULATION LA English DT Letter C1 USN, Hlth Res Ctr, Operat Res Div, Washington, DC 20350 USA. RP Blood, C (reprint author), USN, Hlth Res Ctr, Operat Res Div, Washington, DC 20350 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SIMULATION COUNCILS INC PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92117 USA SN 0037-5497 J9 SIMULATION JI Simulation PD MAY PY 1997 VL 68 IS 5 BP 268 EP 268 PG 1 WC Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering SC Computer Science GA 160EA UT WOS:000078216400002 ER PT J AU Barton, O AF Barton, O TI Approximate fundamental frequency of variable thickness composite plates SO THIN-WALLED STRUCTURES LA English DT Article ID RECTANGULAR-PLATES; VIBRATION AB An approximate closed-form expression is presented which can be used to compute the fundamental frequency of symmetric rectangular composite laminates of variable thickness. The desired expression is developed using the method of eigensensitivity analysis. Results are presented for a parabolic thickness variation in one direction, with the taper parameter beta varying from 0.5 to 1.5, various plate aspect ratio R and a high material stiffness ratio E-11/E-22 using both simply supported and clamped boundary conditions. Comparison of the predicted fundamental frequencies with those numerically computed, using the Rayleigh-Ritz method, demonstrates the utility and accuracy of the expression. (C) 1997 Published by Elsevier Science Ltd. RP Barton, O (reprint author), USN ACAD,DEPT MECH ENGN,ANNAPOLIS,MD 21402, USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0263-8231 J9 THIN WALL STRUCT JI Thin-Walled Struct. PD MAY PY 1997 VL 28 IS 1 BP 43 EP 55 DI 10.1016/S0263-8231(97)00006-2 PG 13 WC Engineering, Civil SC Engineering GA XY610 UT WOS:A1997XY61000003 ER PT J AU Arthur, RR Hassan, NF Abdallah, MY ElSharkawy, MS Saad, MD Hackbart, BG Imam, IZ AF Arthur, RR Hassan, NF Abdallah, MY ElSharkawy, MS Saad, MD Hackbart, BG Imam, IZ TI Hepatitis C antibody prevalence in blood donors in different governorates in Egypt SO TRANSACTIONS OF THE ROYAL SOCIETY OF TROPICAL MEDICINE AND HYGIENE LA English DT Article DE hepatitis B; hepatitis C; prevalence; blood donors; Egypt ID HIGH SEROPREVALENCE; VIRUS-INFECTION; UNITED-STATES; RISK; HCV AB Markers of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections were sought in serum samples from 2644 blood donors in 24 of Egypt's 26 governorates. Of the 2644 samples, 656 (24.8%) were shown to contain anti-HCV immunoglobulin G antibody by Abbott second generation enzyme immunoassays (EIA). Of 85 EIA-positive samples tested by recombinant immunoblot assay, 72 (85%) were positive. HCV seroprevalence in the governorates ranged from zero to 38%; 15 governorates (62%) had an HCV antibody prevalence greater than 20%, and 6 (25%) greater than 30%. Governorates with higher sero-prevalences were located in the central and north-eastern Nile river delta, and south of Cairo in the Nile river valley. Subjects from areas in and adjoining the Sinai peninsula, in the eastern and western desert, and in southernmost Egypt, had the lowest prevalence of HCV antibody. The large urban governorates of Cairo and Alexandria had antibody prevalences of 19% and 11%, respectively. A total of 39.4% subjects had evidence of HBV infection (and-HBV core antigen total antibody). HCV infections were detected more frequently in donors with markers for HBV infections than in uninfected subjects (36% versus 18%, P<0.001). C1 USN,MED RES UNIT 3,VIROL BRANCH,CAIRO,EGYPT. JOHNS HOPKINS UNIV,SCH HYG & PUBL HLTH,BALTIMORE,MD. MINIST HLTH CAIRO,CAIRO,EGYPT. RI Saad, Magdi/H-5561-2013 OI Saad, Magdi/0000-0003-2111-8115 NR 19 TC 80 Z9 83 U1 0 U2 1 PU ROYAL SOC TROPICAL MEDICINE PI LONDON PA MANSON HOUSE 26 PORTLAND PLACE, LONDON, ENGLAND W1N 4EY SN 0035-9203 J9 T ROY SOC TROP MED H JI Trans. Roy. Soc. Trop. Med. Hyg. PD MAY-JUN PY 1997 VL 91 IS 3 BP 271 EP 274 DI 10.1016/S0035-9203(97)90070-5 PG 4 WC Public, Environmental & Occupational Health; Tropical Medicine SC Public, Environmental & Occupational Health; Tropical Medicine GA XE698 UT WOS:A1997XE69800009 PM 9231192 ER PT J AU Collins, MD Lingevitch, JF Siegmann, WL AF Collins, MD Lingevitch, JF Siegmann, WL TI Wave propagation in poro-acoustic media SO WAVE MOTION LA English DT Article ID CONSERVING PARABOLIC EQUATION; STEP PADE SOLUTION; SOUND-PROPAGATION; NUMERICAL-METHOD; ELASTIC MEDIA; NORMAL-MODES; OCEAN; REFLECTION; BOTTOM; DEPTH AB Some ocean sediments may be modeled as pore-elastic media with relatively high slow-wave speeds and relatively low shear-wave speeds [N.P. Chotiros, ''Biot model of sound propagation in water-saturated sand'', J. Acoust. Sec. Amer. 97, 199-214 (1995)]. This singular limit may be handled efficiently by allowing the shear modulus to vanish so that shear waves are ignored. This approach reduces the number of equations and permits a relatively coarse numerical grid. The equations of pore-acoustic media are remarkably similar to the equations of acoustic media. The equations of motion are a vector generalization of the variable density wave equation of acoustics [P.G. Bergmann, ''The wave equation in a medium with a variable index of refraction'', J. Acoust. Sec. Amer 17, 329-333 (1946)]. The interface conditions resemble the acoustic conditions for continuity of pressure and particle velocity. The energy-flux integrals of pore-acoustics and acoustics are also similar. C1 RENSSELAER POLYTECH INST,TROY,NY 12180. RP Collins, MD (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 32 TC 12 Z9 12 U1 2 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0165-2125 J9 WAVE MOTION JI Wave Motion PD MAY PY 1997 VL 25 IS 3 BP 265 EP 272 DI 10.1016/S0165-2125(96)00045-5 PG 8 WC Acoustics; Mechanics; Physics, Multidisciplinary SC Acoustics; Mechanics; Physics GA XA282 UT WOS:A1997XA28200003 ER PT J AU Kerrigan, KR Mertz, BL Nelson, SJ Dye, JD AF Kerrigan, KR Mertz, BL Nelson, SJ Dye, JD TI Antibiotic prophylaxis for pit viper envenomation: Prospective, controlled trial SO WORLD JOURNAL OF SURGERY LA English DT Article ID WOUNDS; BACTERIOLOGY; GUIDELINES; SNAKEBITE; THERAPY; VENOM; BITES AB The efficacy of prophylactic antibiotics for preventing infectious complications at the site of pit viper envenomation has not been well studied, We undertook a prospective, controlled trial of antibiotic treatment versus no antibiotic treatment among 114 victims of crotalid envenomation in Ecuador's Amazon rain forest. A group of 59 patients received intravenous gentamicin and chloramphenicol, and 55 patients did not. All other aspects of care were identical. There were no statistically significant differences between antibiotic-treated and untreated patients with regard to demographics, delay in treatment, clinical and laboratory evidence of severity of envenomation, or use of antivenin. Nine abscesses occurred, six in the antibiotic-treated group and three in the untreated group. The results of this study did not show any statistically significant differences in outcome in terms of the number of abscesses that occurred between antibiotic-treated and untreated patients. Based on this lack of differences, routine use of prophylactic antibiotics for prevention of infectious complications of crotalid envenomation cannot be recommended. C1 NAVAL HOSP, DEPT FAMILY PRACTICE, CHARLESTON, SC 29405 USA. HOSP VOZANDES ORIENTE, PASTAZA, ECUADOR. HOSP VOZANDES, QUITO, ECUADOR. NR 27 TC 28 Z9 31 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0364-2313 EI 1432-2323 J9 WORLD J SURG JI World J.Surg. PD MAY PY 1997 VL 21 IS 4 BP 369 EP 373 PG 5 WC Surgery SC Surgery GA WU555 UT WOS:A1997WU55500005 PM 9143566 ER PT J AU Bucca, D Keller, TM AF Bucca, D Keller, TM TI Thermally and oxidatively stable thermosets derived from preceramic monomers SO JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY LA English DT Article DE ethynyl-substituted monomers; inorganic monomers; preceramic monomers; high-performance thermosets; thermal analysis ID CHEMISTRY; RESINS AB Monomers 1,3-bis(4-phenylethynylphenyl)tetramethyldisiloxane and 1,7-bis(4-phenylethynylphenyltetramethyldisiloxy)-m-carborane were synthesized and compared with bis(4-phenylethynylphenyl)dimethylsilane as potential preceramic precursors. These monomers were heated to free flowing liquids above 100 degrees C and thermally polymerized above 300 degrees C to form heat-resistant thermosets or ceramic residues. The ceramic yields for the silane (13%) and siloxane (30%) were much lower than that for the carborane (64%) monomer. The thermoset and ceramic made from the carborane monomer were the best thermally and oxidatively stable materials. After curing, the thermoset had a weight loss of only 6% and after pyrolysis, the ceramic residue had no additional weight loss up to 1000 degrees C in air. (C) 1997 John Wiley & Sons, Inc. C1 USN,RES LAB,MAT CHEM BRANCH,WASHINGTON,DC 20375. NR 12 TC 24 Z9 26 U1 3 U2 8 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0887-624X J9 J POLYM SCI POL CHEM JI J. Polym. Sci. Pol. Chem. PD APR 30 PY 1997 VL 35 IS 6 BP 1033 EP 1038 DI 10.1002/(SICI)1099-0518(19970430)35:6<1033::AID-POLA6>3.0.CO;2-5 PG 6 WC Polymer Science SC Polymer Science GA WQ329 UT WOS:A1997WQ32900006 ER PT J AU Kee, A Matic, P Popels, L AF Kee, A Matic, P Popels, L TI A two dimensional computational study of a gasar porous copper microstructure SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE gasar process; microstructures; yield stress AB The 'gasar' process uses a metal-hydrogen eutectic reaction to produce varied pore morphologies in metals such as copper, magnesium, nickel and aluminum. Experimental observations and unit cell studies of pore deformation interactions in copper 'gasar' materials suggest that the pore microstructure geometry will induce multiaxial states of deformation that contribute to the retention of significant bulk material strength. In this investigation, a two dimensional finite element study of the pore interactions in a 21.5% porosity gasar copper was performed. The finite element model was based upon a micrograph of the actual porosity microstructure. The pore microstructure in this material features a range of elongated pores, averaging 18 mu m in diameter and 108 mu m in length and accounting for 18% of the total porosity. Different in-plane and out-of-plane constraint combinations were studied. The results of these simulations show the development of very nonuniform mesoscale stress and strain patterns across the microstructure. These patterns are produced as a consequence of pore shape, pore spacing, pore free zones and spatial offsets. The results support the conclusions of earlier unit cell studies on the role that these features play in bulk properties. (C) 1997 Elsevier Science S.A. C1 USN,RES LAB,MECH MAT BRANCH,WASHINGTON,DC 20375. GEOCENTERS INC,FT WASHINGTON,MD 20744. NR 9 TC 7 Z9 10 U1 1 U2 2 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD APR 30 PY 1997 VL 225 IS 1-2 BP 85 EP 95 DI 10.1016/S0921-5093(96)10878-9 PG 11 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA XK183 UT WOS:A1997XK18300010 ER PT J AU Cross, JO Bennett, BR Bell, MI Kuhn, KJ AF Cross, JO Bennett, BR Bell, MI Kuhn, KJ TI Synthetic wide bandpass x-ray polarizers SO APPLIED PHYSICS LETTERS LA English DT Article ID SCATTERING; DIFFRACTION; STATE AB A wide bandpass x-ray polarizer for photon energies near 8358 eV (L-III absorption edge of erbium) has been grown using molecular beam epitaxy. The results illustrate a general approach to preparing graded-lattice diffracting optical components. The active optical element is an 8-mu m-thick single crystal film of In0.51Ga0.49Sb grown on a GaAs (001) substrate. The alloy was chosen to ensure maximum linear polarization for the (006) Bragg reflection at the target energy. The polarizer reflectivity has a full width at half-maximum of 27 eV in a fixed geometry with an angle of 90 degrees between the incident and diffracted beams. (C) 1997 American Institute of Physics. C1 INTEL CORP,HILLSBORO,OR 97195. RP Cross, JO (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. RI Bennett, Brian/A-8850-2008 OI Bennett, Brian/0000-0002-2437-4213 NR 13 TC 1 Z9 1 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 28 PY 1997 VL 70 IS 17 BP 2224 EP 2226 DI 10.1063/1.118822 PG 3 WC Physics, Applied SC Physics GA WW272 UT WOS:A1997WW27200004 ER PT J AU Chow, GM Kurihara, LK Ma, D Feng, CR Schoen, PE MartinezMiranda, LJ AF Chow, GM Kurihara, LK Ma, D Feng, CR Schoen, PE MartinezMiranda, LJ TI Alternative approach to electroless Cu metallization of AlN by a nonaqueous polyol process SO APPLIED PHYSICS LETTERS LA English DT Article ID COPPER; SUBSTRATE; POWDERS AB Cu metallization of AIN substrates was performed using a nonaqueous, electroless; alcohol based approach known as the polyol method. The concentration of Cu2O in the film depended on the orientation of the substrates during deposition. This approach is very attractive for metallizing electronic substrates which are susceptible to hydrolytic degradation. (C) 1997 American Institute of Physics. C1 USN,RES LAB,LAB MOL INTERFACIAL INTERACT,WASHINGTON,DC 20375. USN,RES LAB,DIV ELECT SCI & TECHNOL,WASHINGTON,DC 20375. UNIV MARYLAND,DEPT MAT & NUCL ENGN,COLLEGE PK,MD 20742. RP Chow, GM (reprint author), USN,RES LAB,DIV MAT SCI & TECHNOL,WASHINGTON,DC 20375, USA. NR 12 TC 33 Z9 33 U1 2 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 28 PY 1997 VL 70 IS 17 BP 2315 EP 2317 DI 10.1063/1.118847 PG 3 WC Physics, Applied SC Physics GA WW272 UT WOS:A1997WW27200035 ER PT J AU Shenenberger, DW Kiser, WR AF Shenenberger, DW Kiser, WR TI Neonatal circumcision SO LANCET LA English DT Letter RP Shenenberger, DW (reprint author), NAVAL HOSP,DEPT FAMILY PRACTICE,JACKSONVILLE,FL 32214, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU LANCET LTD PI LONDON PA 42 BEDFORD SQUARE, LONDON, ENGLAND WC1B 3SL SN 0140-6736 J9 LANCET JI Lancet PD APR 26 PY 1997 VL 349 IS 9060 BP 1257 EP 1257 DI 10.1016/S0140-6736(05)62458-0 PG 1 WC Medicine, General & Internal SC General & Internal Medicine GA WW717 UT WOS:A1997WW71700065 PM 9130978 ER PT J AU Klimchuk, JA AF Klimchuk, JA TI Plasma physics - Magnetic energy release on the Sun SO NATURE LA English DT Editorial Material ID SOLAR RP Klimchuk, JA (reprint author), USN,RES LAB,EO HULBURT CTR SPACE RES,4555 OVERLOOK AVE SW,CODE 7675JAK,BLDG 209,ROOM 1,WASHINGTON,DC 20375, USA. RI Klimchuk, James/D-1041-2012 OI Klimchuk, James/0000-0003-2255-0305 NR 13 TC 4 Z9 4 U1 0 U2 0 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD APR 24 PY 1997 VL 386 IS 6627 BP 760 EP 761 DI 10.1038/386760a0 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA WV706 UT WOS:A1997WV70600026 ER PT J AU Sprangle, P Hafizi, B Hubbard, RF AF Sprangle, P Hafizi, B Hubbard, RF TI Ionization and pulse lethargy effects in inverse Cherenkov accelerators SO APPLIED PHYSICS LETTERS LA English DT Article ID LASER ACCELERATION; ELECTRONS; BEAM AB Ionization processes and pulse lethargy limit the pulse duration, accelerating gradient, and maximum energy gain in the inverse Cherenkov accelerator (ICA). These limits are obtained for two ICA waveguide configurations: (i) lined with a dielectric or (ii) filled with a neutral gas. Ionization of the dielectric or gas, by the electromagnetic driver, can modify the dispersive properties, altering the accelerating field phase velocity, causing particle slippage, and disrupting the acceleration. In addition, the electrons can outrun the pulse (pulse lethargy), terminating the acceleration. Limitations due to ionization and pulse lethargy on the accelerating gradient, pulse duration, and maximum energy gain are obtained and illustrated by several examples. (C) 1997 American Institute of Physics. RP Sprangle, P (reprint author), USN,RES LAB,DIV PLASMA PHYS,BEAM PHYS BRANCH,WASHINGTON,DC 20375, USA. NR 22 TC 2 Z9 2 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 21 PY 1997 VL 70 IS 16 BP 2198 EP 2200 DI 10.1063/1.119040 PG 3 WC Physics, Applied SC Physics GA WU601 UT WOS:A1997WU60100045 ER PT J AU Woodfield, BF Wilson, ML Byers, JM AF Woodfield, BF Wilson, ML Byers, JM TI Low-temperature specific heat of La1-xSrxMnO3+delta SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTRONIC-STRUCTURE; METAL TRANSITION AB The specific heat of the perovskite manganite La1-xSrxMnO3+delta was measured in the doping regime x = 0.0 to 0.3 where at low temperatures the material changes from a layered antiferromagnetic insulator to a ferromagnetic metal. A term in the specific heat, C proportional to T-2, is found in LaMnO3 that is attributable to spin excitations in a layered antiferromagnet. Ferromagnetic samples have the expected specific heat term C proportional to T-3/2 due to ferromagnetic spin waves. The exchange coupling (J), electronic linear term (gamma), Debye temperature (theta(D)), and the local field at the Mn site (H-hyp) are extracted from the specific heat as functions of Sr doping. C1 USN,RES LAB,WASHINGTON,DC 20375. NR 32 TC 169 Z9 170 U1 1 U2 16 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 21 PY 1997 VL 78 IS 16 BP 3201 EP 3204 DI 10.1103/PhysRevLett.78.3201 PG 4 WC Physics, Multidisciplinary SC Physics GA WU621 UT WOS:A1997WU62100044 ER PT J AU Rohr, J Allen, J Losee, J Latz, MI AF Rohr, J Allen, J Losee, J Latz, MI TI The use of bioluminescence as a flow diagnostic SO PHYSICS LETTERS A LA English DT Article DE bioluminescence; laminar; pipe flow; plankton; turbulence; shear ID TURBULENCE; EXCITATION; PIPE AB The flash response of luminescent plankton is studied in laminar and turbulent pipe flow. Maximum intensity levels of individual plankton are nearly constant for wall shear stress values exceeding approximately 10 dyn cm(-2) -regardless of the nature of the flow. This result necessitates a reevaluation of previous inferences made about the stimulating flow field. (C) 1997 Published by Elsevier Science B.V. C1 UNIV CALIF SAN DIEGO,SCRIPPS INST OCEANOG,DIV MARINE BIOL RES,LA JOLLA,CA 92093. RP Rohr, J (reprint author), USN,COMMAND CONTROL & OCEAN SURVEILLANCE CTR,53475 STROTHE RD,SAN DIEGO,CA 92152, USA. NR 31 TC 17 Z9 18 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD APR 21 PY 1997 VL 228 IS 6 BP 408 EP 416 DI 10.1016/S0375-9601(97)00034-0 PG 9 WC Physics, Multidisciplinary SC Physics GA WV395 UT WOS:A1997WV39500013 ER PT J AU Piner, BG Kingham, KA AF Piner, BG Kingham, KA TI VLBI observations of the gamma-ray blazar 1611+343 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies, jets; galaxies, kinematics and dynamics; galaxies, structure; gamma rays, theory; quasars, individual (1611 + 343); radio continuum, galaxies ID FREQUENCY VARIABLE SOURCES; ACTIVE GALACTIC NUCLEI; DOMINATED RADIO-SOURCES; SUPERLUMINAL MOTION; BL LACERTAE; SAMPLE; GHZ; GEODESY; CORE; INTERFEROMETRY AB As part of an effort to observe high-energy gamma-ray blazars with VLBI, we have produced 8 and 2 GHz VLBI images, at eight epochs, of the quasar 1611+343, which has been detected by the EGRET telescope on board the Compton Gamma Ray Observatory. The VLBI data have been taken from the geodetic database of the Washington VLBI correlator. As is expected for a gamma-ray quasar, we find that 1611+343 possesses a jet with several compact components moving at apparent superluminal speeds. We have detected five components and have measured speeds for the outer four of 6.7 +/- 1.6, 3.8 +/- 1.4, 7.6 +/- 1.3, and 11.5 +/- 2.3 h(-1)c from the outermost component inward. (H-0 = 100 h km s(-1) Mpc(-1), q(0) = 0.5.) By comparing the apparent superluminal expansion speeds with a lower limit to the Doppler beaming factor derived from X-ray observations, we have calculated an upper limit on the angle of the jet to the line of sight of theta less than or equal to 6.degrees 8 and a lower limit to the Lorentz factor of the components of Gamma greater than or equal to 7.1. We have mapped the two-dimensional projected structure of the VLBI jet and clearly see different trajectories for different components at the same distance from the core, which rules out a continuous jet model for this source. A possible connection is found between enhanced levels of gamma-ray activity and the ejection of new VLBI components from the core. C1 USN OBSERV,EARTH ORIENTAT DEPT,WASHINGTON,DC 20392. NR 57 TC 22 Z9 22 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 1997 VL 479 IS 2 BP 684 EP 693 DI 10.1086/303919 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA WU505 UT WOS:A1997WU50500017 ER PT J AU Tavani, M Mukherjee, R Mattox, JR Halpern, J Thompson, DJ Kanbach, G Hermsen, W Zhang, SN Foster, RS AF Tavani, M Mukherjee, R Mattox, JR Halpern, J Thompson, DJ Kanbach, G Hermsen, W Zhang, SN Foster, RS TI Discovery of a nonblazar gamma-ray transient source near the Galactic plane: GRO J1838-04 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies, active; gamma rays, observations; stars, neutron ID J1655-40; EMISSION AB We report the discovery of a remarkable gamma-ray transient source near the Galactic plane, GRO J1838-04. This source was serendipitously discovered by EGRET in 1995 June with a peak intensity of similar to(4 +/- 1) x 10(-6) photons cm(-2) s(-1) (for photon energies larger than 100 MeV) and a 5.9 sigma significance. At that time, GRO J1838-04 was the second brightest gamma-ray source in the sky, A subsequent EGRET pointing in 1995 late September detected the source at a flux smaller than its peak value by a factor of similar to 7. We determine that no radio-loud spectrally flat blazar is within the error box of GRO J1838-04. We discuss the origin of the gamma-ray transient source and show that interpretations in terms of active galactic nuclei or isolated pulsars are highly problematic. GRO J1838-04 provides strong evidence for the existence of a new class of variable gamma-ray sources. C1 MCGILL UNIV, DEPT PHYS, MONTREAL, PQ H3A 2T8, CANADA. BOSTON UNIV, DEPT ASTRON, BOSTON, MA 02215 USA. MPE, D-85748 GARCHING, GERMANY. SRON UTRECHT, NL-3584 CA UTRECHT, NETHERLANDS. UNIV SPACE RES ASSOC, NASA, MSFC, HUNTSVILLE, AL 35812 USA. USN, RES LAB, WASHINGTON, DC 20375 USA. UNIV SPACE RES ASSOC, NASA, GODDARD SPACE FLIGHT CTR, GREENBELT, MD 20771 USA. RP Tavani, M (reprint author), COLUMBIA UNIV, COLUMBIA ASTROPHYS LAB, 538 W 120TH ST, NEW YORK, NY 10027 USA. RI Thompson, David/D-2939-2012 OI Thompson, David/0000-0001-5217-9135 NR 21 TC 35 Z9 35 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 1997 VL 479 IS 2 BP L109 EP L112 DI 10.1086/310603 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA WU506 UT WOS:A1997WU50600008 ER PT J AU Sandor, BJ Clancy, RT Rusch, DW Randall, CE Eckman, RS Siskind, DS Muhleman, DO AF Sandor, BJ Clancy, RT Rusch, DW Randall, CE Eckman, RS Siskind, DS Muhleman, DO TI Microwave observations and modeling of O-2((1)Delta(g)) and O-3 diurnal variation in the mesosphere SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID LOWER THERMOSPHERE; WATER-VAPOR; OZONE; PROFILES; OXYGEN; FRACTIONATION; SPECTROMETER; STRATOSPHERE; ATMOSPHERE; EXPLORER AB The first microwave measurements of an electronically excited molecular species in the Earth's atmosphere are presented. Local thermodynamic equilibrium (LTE) rotational line emission from mesospheric O-2((1) Delta(g)) was observed at a frequency of 255.01794 GHz (lambda similar to 1.2 mm), employing the National Radio Astronomy Observatory (NRAO) millimeter facility at Kitt Peak, Arizona (32 degrees N, 111 degrees W). The pressure-broadened line shapes of the O-2((1) Delta(g)) spectra, which were obtained in January and April 1992 and in January and November 1993, are inverted to retrieve O-2((1) Delta(g)) mixing profiles over the 50-70 km altitude region. The observed daytime abundances exceed ozone abundances in the lower mesosphere, which are separately retrieved with coincident O-3 spectral line (249.7886 GHz) observations. The January and November 1993 observations are binned into 20-60 min time intervals to study O-2((1) Delta(g)) diurnal behavior. Derived abundances of O-2((1) Delta(g)) between 50 and 70 km for the four observation dates are 9%, 31%, 3%, and 26%, respectively, each +/-10% higher than predicted, based on the simple photochemistry of lower mesospheric O-2((1) Delta(g)). Modeled variation of [O-2((1) Delta(g))] with time of day agrees with observed variation in that the observed difference between model and data abundances is constant throughout the daylight hours of each observation date. Model underprediction of [O-2((1) Delta(g))] is consistent with similar model underprediction of mesospheric [O-3]. A perturbation to the photochemical model that forces decreased ozone chemical loss brings brings both model [O-3] and [O-2((1) Delta(g))] into agreement with the observations. O-2((1) Delta(g)) abundances derived from these 1.2 mm observations agree with [O-2((1) Delta(g))] values derived from comparable SME observations of the 1.27 mu m emission, with assumption of a 3880 s O-2((1) Delta(g)) radiative lifetime [Badger et al., 1965]. The 6800 s O-2((1) Delta(g)) radiative lifetime proposed by Mlynczak and Nesbitt [1995] is ruled out by the similar comparison. C1 SPACE SCI INST, BOULDER, CO 80303 USA. NASA, LANGLEY RES CTR, DIV ATMOSPHER SCI, HAMPTON, VA 23681 USA. CALTECH, DIV GEOL & PLANETARY SCI, PASADENA, CA 91125 USA. UNIV COLORADO, LAB ATMOSPHER & SPACE PHYS, BOULDER, CO 80309 USA. USN, RES LAB, WASHINGTON, DC 20375 USA. RP Sandor, BJ (reprint author), CALTECH, JET PROP LAB, MAIL STOP 183-701, 4800 OAK GROVE DR, PASADENA, CA 91109 USA. RI Randall, Cora/L-8760-2014 OI Randall, Cora/0000-0002-4313-4397 NR 43 TC 20 Z9 20 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 20 PY 1997 VL 102 IS D7 BP 9013 EP 9028 DI 10.1029/96JD03585 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA WX558 UT WOS:A1997WX55800028 ER PT J AU Edgar, JH Smith, DT Eddy, CR Carosella, CA Sartwell, BD AF Edgar, JH Smith, DT Eddy, CR Carosella, CA Sartwell, BD TI c-Boron aluminum nitride alloys prepared by ion-beam assisted deposition SO THIN SOLID FILMS LA English DT Article DE boron nitride; aluminium nitride; ion-beam-assisted deposition ID FILMS; STRESS AB The structure, mechanical, and chemical properties of boron-aluminum nitride thin films prepared by ion-beam-assisted deposition (IBAD) are reported. The ratio of N to Al + B as determined by Auger electron spectroscopy was consistently 1.0 in all films. The c-lattice constant of the alloy decreased linearly up to approximately 10% BN, suggesting the formation of a single-phase AlN-wurtzite-BN alloy. The hardness of the films was between 20 and 25 GPa, as measured by nanoindentation, and did not change significantly with the amount of boron present. The etch rate in warm phosphoric acid of an alloy containing 9% BN was an order of magnitude lower than that of pure AlN. C1 NIST,DIV CERAM,GAITHERSBURG,MD 20899. USN,RES LAB,WASHINGTON,DC 20375. RP Edgar, JH (reprint author), KANSAS STATE UNIV,DEPT CHEM ENGN,DURLAND HALL,MANHATTAN,KS 66506, USA. RI Smith, Douglas/I-4403-2016 OI Smith, Douglas/0000-0002-9358-3449 NR 22 TC 21 Z9 22 U1 0 U2 10 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD APR 20 PY 1997 VL 298 IS 1-2 BP 33 EP 38 DI 10.1016/S0040-6090(96)08884-0 PG 6 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA XH324 UT WOS:A1997XH32400005 ER PT J AU Li, YB BlaistenBarojas, E Papaconstantopoulos, DA AF Li, YB BlaistenBarojas, E Papaconstantopoulos, DA TI Molecular dynamics study of neutral and multiply charged sodium clusters SO CHEMICAL PHYSICS LETTERS LA English DT Article ID ALKALI-METAL CLUSTERS; ASYMMETRIC FISSION; DISSOCIATION; BARRIERS AB The fission mechanism of multiply charged sodium clusters was investigated with molecular dynamics and a new potential featuring a local density approximation second-moment approach. We show that the critical size at which 2+, 3+ and 4+ charged clusters undergo fission due to Coulomb forces depends strongly on the cluster temperature. The smallest critical sizes occur for cold clusters. Master curves predicting upper bounds to the cluster temperature at the fissioning critical size are provided. A scaling of the cluster ion critical size with a power law of the total charge is used to predict the energy barrier that sodium clusters need to surmount to undergo fission. (C) 1997 Elsevier Science B.V. C1 USN,RES LAB,COMPLEX SYST THEORY BRANCH,WASHINGTON,DC 20375. RP Li, YB (reprint author), GEORGE MASON UNIV,INST COMPUTAT SCI & INFORMAT,FAIRFAX,VA 22030, USA. NR 30 TC 13 Z9 14 U1 2 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD APR 18 PY 1997 VL 268 IS 5-6 BP 331 EP 336 DI 10.1016/S0009-2614(97)00208-X PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA WU702 UT WOS:A1997WU70200004 ER PT J AU McNesby, KL Coffey, CS AF McNesby, KL Coffey, CS TI Spectroscopic determination of impact sensitivities of explosives SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID HOT-SPOT FORMATION; INITIATION; PROPELLANT; MODEL AB A simple theory is developed which predicts impact sensitivities in crystalline explosives from vibrational spectra measured at room temperature. The theory uses Raman spectra of energetic materials to construct vibrational energy level diagrams, which are then used as input for a model designed to calculate the rate of energy transfer from phonon and near-phonon vibrational energy levels to higher energy vibrational levels, Energy transfer rates are determined using Fermi's Golden Rule and results from simple theories of near-resonant energy transfer. The application of the theory and model, using Raman spectra of seven different neat explosive samples, gives results in good agreement with results of drop weight impact tests. C1 USN,CTR SURFACE WARFARE,SILVER SPRING,MD 20903. RP McNesby, KL (reprint author), USA,RES LAB,ABERDEEN PROVING GROUND,MD 21005, USA. NR 29 TC 75 Z9 81 U1 2 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD APR 17 PY 1997 VL 101 IS 16 BP 3097 EP 3104 DI 10.1021/jp961771l PG 8 WC Chemistry, Physical SC Chemistry GA WU630 UT WOS:A1997WU63000013 ER PT J AU Callahan, DA Langdon, AB Friedman, A Haber, I AF Callahan, DA Langdon, AB Friedman, A Haber, I TI The longitudinal wall impedance instability in a heavy-ion fusion driver SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ACCELERATOR; TARGET; BEAM AB For more than ten years [J. Bisognano, I. Haber, L, Smith, IEEE Trans, Nucl, Sci, NS-30, 2501 (1983)], the longitudinal wall impedance instability was thought to be a serious threat to the success of heavy-ion driven inertial confinement fusion. This instability is a ''resistive wall'' instability, driven by the impedance of the induction modules used to accelerate the beam. Early estimates of the instability growth rate predicted tells of e-folds due to the instability which would modulate the current and increase the longitudinal momentum spread and prevent focusing the ion beam on the small spot needed at the target. We have simulated this instability using an r-z particle-in-cell code which includes a model for the module impedance. These simulations, using driver parameters, show that growth due to the instability is smaller than in previous calculations. We have seen that growth is mainly limited to one head to tail transit by a space-charge wave. In addition, the capacitive component of the module impedance, which was neglected in the early work of Lee [E, P. Lee, Proc, Linear Accelerator Conference, (UCRL-86452), Santa Fe, NM, 1981] significantly reduces the growth rate. We have also included in the simulation intermittently applied axial confining fields which are thought to be the major source of perturbations to seed the longitudinal instability. Simulations show the beam can adjust to a systematic error in the longitudinal confining fields while a random error er;cites the most unstable wavelength of the instability. These simulations show that the longitudinal instability must be taken into account in a driver design, but it is not the major factor it was once thought to be, (C) 1997 American Institute of Physics. C1 USN,RES LAB,WASHINGTON,DC 20375. RP Callahan, DA (reprint author), LAWRENCE LIVERMORE NATL LAB,POB 808,LIVERMORE,CA 94550, USA. NR 18 TC 3 Z9 3 U1 1 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1997 VL 81 IS 8 BP 3398 EP 3409 DI 10.1063/1.365035 PN 1 PG 12 WC Physics, Applied SC Physics GA WV363 UT WOS:A1997WV36300010 ER PT J AU Tschopp, S Robins, G Stamps, RL Sooryakumar, R Filipkowski, ME Gutierrez, CJ Prinz, GA AF Tschopp, S Robins, G Stamps, RL Sooryakumar, R Filipkowski, ME Gutierrez, CJ Prinz, GA TI Observation of magnons by light scattering in epitaxial CoFe/Mn/CoFe trilayers SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 41st Annual Conference on Magnetism and Magnetic Materials CY NOV 12-15, 1996 CL ATLANTA, GA SP Amer Inst Phys ID FILMS AB We report on Brillouin scattering measurements on a CoFe/Mn/CoFe trilayer film characterized by unusually large biquadratic coupling. The magnetic field dependence of the exchange coupled in- and out-of-phase magnons as well as their in-plane directional dependence are determined. The saturation magnetization of the trilayer was measured independently through superconducting quantum interference device magnetometry. The spin wave data is well represented by a generalization of the model that takes into account the antiferromagnetic order in the Mn layer. (C) 1997 American Institute of Physics. C1 UNIV ARKANSAS,DEPT PHYS,FAYETTEVILLE,AR 72701. SW TEXAS STATE UNIV,DEPT PHYS,SAN MARCOS,TX 78666. USN,RES LAB,WASHINGTON,DC 20375. RP Tschopp, S (reprint author), OHIO STATE UNIV,DEPT PHYS,174 W 18TH AVE,COLUMBUS,OH 43210, USA. RI Stamps, Robert/E-7304-2011 OI Stamps, Robert/0000-0003-0713-4864 NR 8 TC 4 Z9 4 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1997 VL 81 IS 8 BP 3785 EP 3787 DI 10.1063/1.364769 PN 2A PG 3 WC Physics, Applied SC Physics GA WV536 UT WOS:A1997WV53600017 ER PT J AU Snyder, JE Harris, VG Harrell, JW Parker, FT Kitahata, S AF Snyder, JE Harris, VG Harrell, JW Parker, FT Kitahata, S TI Local structure of as-prepared and partially reduced Co,Ti,Sn-substituted Ba-hexaferrite powder SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 41st Annual Conference on Magnetism and Magnetic Materials CY NOV 12-15, 1996 CL ATLANTA, GA SP Amer Inst Phys ID FERRITE AB In this study, the local structure around Fe and Co atoms in as-prepared and partially reduced Co,Ti,Sn-substituted Ba-hexaferrite powders are examined using extended x-ray absorption fine structure (EXAFS). It appears that the substitutional atoms in general and Co in particular show a preference for the Fe(IV) and Fe(III) sites. After partial reduction in H-2 at 300 degrees C, both the Fe and Co EXAFS show a mixture of two phases: substituted Ba-hexaferrite and bce metal. There does not appear to be any large preference in reduction among the five different types of Fe sites. However, a much larger fraction of the Co is reduced than is the Fe. Thus the partially reduced sample is not merely a collection of unreduced and totally reduced particles. The after-reduction spectra for both Fe and Co EXAFS were fit using a linear combination of spectra from as-prepared material and bcc metal, which enabled quantitative calculation of the relative fraction of each metal reduced. (C) 1997 American Institute of Physics. C1 UNIV ALABAMA,MINT CTR,TUSCALOOSA,AL 35487. UNIV CALIF SAN DIEGO,CMRR,LA JOLLA,CA 92093. HITACHI MAXELL LTD,ENGN RES LAB,HITACHI,IBARAKI 30024,JAPAN. RP Snyder, JE (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. RI Harris, Vincent/A-8337-2009 NR 11 TC 3 Z9 3 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1997 VL 81 IS 8 BP 3824 EP 3826 DI 10.1063/1.364782 PN 2A PG 3 WC Physics, Applied SC Physics GA WV536 UT WOS:A1997WV53600030 ER PT J AU Idzerda, YU Chakarian, V Kemner, KM Elam, WT AF Idzerda, YU Chakarian, V Kemner, KM Elam, WT TI Magnetic extended x-ray absorption fine structure of transition metal films and alloys SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract C1 USN,RES LAB,WASHINGTON,DC 20375. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1997 VL 81 IS 8 BP 3918 EP 3918 DI 10.1063/1.365070 PN 2A PG 1 WC Physics, Applied SC Physics GA WV536 UT WOS:A1997WV53600069 ER PT J AU Miller, MM Prinz, GA Lubitz, P Hoines, L Krebs, JJ Cheng, SF Parsons, FG AF Miller, MM Prinz, GA Lubitz, P Hoines, L Krebs, JJ Cheng, SF Parsons, FG TI Novel absolute linear displacement sensor utilizing giant magnetoresistance elements SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 41st Annual Conference on Magnetism and Magnetic Materials CY NOV 12-15, 1996 CL ATLANTA, GA SP Amer Inst Phys ID SUPERLATTICES; MULTILAYERS AB A novel concept for an absolute linear displacement sensor utilizing giant magnetoresistance elements is introduced. This device is based on the division of a magnetically soft layer of a spin-valve device into two antiparallel magnetic domains. The total resistance of the spin valve varies linearly with displacement of the domain wall because of different resistances of the aligned and antialigned magnetic states of the spin valve. Domain-wall translation is achieved by the use of a magnetic wall ''trap'' generated by permanent magnets. Displacement is thus related directly to the device resistance. Position resolution to date is on the order of 10 mu m over ranges of approximately 2 cm and on the order of a micron over reduced ranges. Magnetic hysteresis yields backlash on the order of tens of microns. C1 USN,CTR SURFACE WARFARE,WHITE OAK,MD 20903. FED PROD CO,PROVIDENCE,RI 02940. RP Miller, MM (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 8 TC 14 Z9 17 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1997 VL 81 IS 8 BP 4284 EP 4286 DI 10.1063/1.364802 PN 2A PG 3 WC Physics, Applied SC Physics GA WV536 UT WOS:A1997WV53600204 ER PT J AU Jonker, BT Kneedler, EM Thibado, P Glembocki, OJ Whitman, LJ Bennett, BR AF Jonker, BT Kneedler, EM Thibado, P Glembocki, OJ Whitman, LJ Bennett, BR TI Schottky barrier formation for Fe on GaAs(001) and the role of interfacial structure SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract C1 USN,RES LAB,WASHINGTON,DC 20375. RI Bennett, Brian/A-8850-2008; Whitman, Lloyd/G-9320-2011 OI Bennett, Brian/0000-0002-2437-4213; Whitman, Lloyd/0000-0002-3117-1174 NR 0 TC 14 Z9 14 U1 1 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1997 VL 81 IS 8 BP 4362 EP 4362 DI 10.1063/1.364822 PN 2A PG 1 WC Physics, Applied SC Physics GA WV536 UT WOS:A1997WV53600234 ER PT J AU Singh, DJ AF Singh, DJ TI Magnetism and electronic structure of (La,Ba)CoO3 SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract C1 USN,RES LAB,COMPLEX SYST THEORY BRANCH,WASHINGTON,DC 20375. RI Singh, David/I-2416-2012 NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1997 VL 81 IS 8 BP 4416 EP 4416 DI 10.1063/1.364893 PN 2A PG 1 WC Physics, Applied SC Physics GA WV536 UT WOS:A1997WV53600257 ER PT J AU Kneedler, EM Jonker, BT AF Kneedler, EM Jonker, BT TI Kerr effect study of the onset of magnetization in Fe films on GaAs(001)-2x4 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 41st Annual Conference on Magnetism and Magnetic Materials CY NOV 12-15, 1996 CL ATLANTA, GA SP Amer Inst Phys ID EPITAXIAL-GROWTH; GAAS AB We have studied the magnetic behavior of epitaxial bcc Fe(001) films grown on molecular beam epitaxy-prepared GaAs(001)-2X4 substrates, with film thicknesses ranging up to similar to 16 monolayers (ML) (similar to 23 Angstrom). We present measurements of the thickness-dependent evolution of the magnetic properties of the Fe films as determined by in situ magneto-optical Kerr effect. Particular attention is given to the substrate-induced in-plane uniaxial magnetic anisotropy. We find that the onset of room-temperature ferromagnetism occurs between 4 and 8 ML, and that the anisotropy is dominated by a uniaxial in-plane component such that the two [110] axes are inequivalent for all coverages studied. Although the initial nucleation and growth results in 2D islands elongated along [(1) over bar 10], the in plane easy axis is perpendicular to this direction along [110], indicating that shape anisotropy does not play a significant role. (C) 1997 American Institute of Physics. RP Kneedler, EM (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 10 TC 13 Z9 14 U1 1 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1997 VL 81 IS 8 BP 4463 EP 4465 DI 10.1063/1.364977 PN 2A PG 3 WC Physics, Applied SC Physics GA WV536 UT WOS:A1997WV53600276 ER PT J AU Chakarian, V Idzerda, YU AF Chakarian, V Idzerda, YU TI Total electron yield method in x-ray absorption spectroscopy: A closer look at the saturation/self-absorption effects SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract C1 USN,RES LAB,WASHINGTON,DC 20375. NR 0 TC 8 Z9 8 U1 1 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1997 VL 81 IS 8 BP 4709 EP 4709 DI 10.1063/1.365534 PN 2A PG 1 WC Physics, Applied SC Physics GA WV536 UT WOS:A1997WV53600368 ER PT J AU Williams, CM Harris, VG AF Williams, CM Harris, VG TI Magnetization and coercive force of pulsed laser deposited MnZn-ferrite single crystal films SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract C1 USN,RES LAB,WASHINGTON,DC 20375. MORGAN STATE UNIV,DEPT PHYS,BALTIMORE,MD 21239. RI Harris, Vincent/A-8337-2009 NR 0 TC 0 Z9 0 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1997 VL 81 IS 8 BP 4800 EP 4800 DI 10.1063/1.364741 PN 2B PG 1 WC Physics, Applied SC Physics GA WV537 UT WOS:A1997WV53700020 ER PT J AU Jonker, BT Yu, WY Salib, MS Petrou, A Warnock, J AF Jonker, BT Yu, WY Salib, MS Petrou, A Warnock, J TI Electron and hole excitonic spin population inversions in strained semimagnetic semiconductor quantum wells SO JOURNAL OF APPLIED PHYSICS LA English DT Meeting Abstract C1 USN,RES LAB,WASHINGTON,DC 20375. SUNY BUFFALO,BUFFALO,NY 14260. IBM CORP,THOMAS J WATSON RES CTR,YORKTOWN HTS,NY 10598. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1997 VL 81 IS 8 BP 4861 EP 4861 DI 10.1063/1.364858 PN 2B PG 1 WC Physics, Applied SC Physics GA WV537 UT WOS:A1997WV53700041 ER PT J AU Wilson, ML Byers, JM Dorsey, PC Horwitz, JS Chrisey, DB Osofsky, MS AF Wilson, ML Byers, JM Dorsey, PC Horwitz, JS Chrisey, DB Osofsky, MS TI Effects of defects on magnetoresistivity in La0.7Sr0.3MnO3 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 41st Annual Conference on Magnetism and Magnetic Materials CY NOV 12-15, 1996 CL ATLANTA, GA SP Amer Inst Phys ID GIANT MAGNETORESISTANCE; DOUBLE-EXCHANGE; LA1-XSRXMNO3; RESISTIVITY AB The effects of structural and oxygen site defects on the ferromagnetic phase transition and magnetotransport in doped lanthanum manganite films have been examined. Oxygen defects were introduced through a vacuum annealing process while structural defects were introduced using ion irradiation. The introduction of both defect types strongly suppressed the Curie temperature T-c while increasing the peak resistivity, activation energy, and magnetoresistance ratio. For defect types leading to similar reductions in T-c, structural defects lead to a broader transition regime and a smaller MRR than are found for oxygen defects. Well above T-c both defect types lead to nearly identical resistivity curves. Structural defects are argued to primarily affect the carrier mobility, hence these data provide a clue that the carrier mobility is dominating the transport properties in this regime. C1 USN,RES LAB,WASHINGTON,DC 20375. RI Osofsky, Michael/A-1050-2010 NR 16 TC 55 Z9 56 U1 1 U2 10 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1997 VL 81 IS 8 BP 4971 EP 4973 DI 10.1063/1.365016 PN 2B PG 3 WC Physics, Applied SC Physics GA WV537 UT WOS:A1997WV53700085 ER EF