FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Cypher, BL Frost, N AF Cypher, BL Frost, N TI Condition of San Joaquin kit foxes in urban and exurban habitats SO JOURNAL OF WILDLIFE MANAGEMENT LA English DT Article DE blood chemistry; California; condition indices; endangered species; mass; San Joaquin kit fox; urban habitat; viral diseases; Vulpes macrotis mutica ID VULPES-MACROTIS-MUTICA; HEMATOLOGIC VALUES; BLOOD PROFILES; COYOTES; POPULATIONS; INDICATORS; WOLVES; URINE; SERUM; FOOD AB We compared condition of endangered San Joaquin kit foxes (Vulpes macrotis mutica) between an urban population in Bakersfield, California (BAK), and a nearby exurban population at the Naval Petroleum Reserves in California (NPRC). Our objective was to determine whether differences between urban and exurban environments, particularly food availability and disease vectors, were reflected in kit fox condition. Body mass, blood chemistry, and prevalence of viral antibodies were assessed at both sites in 1988 and 1989. Body mass was higher for BAK kit foxes, particularly juveniles, and varied between years for NPRC kit foxes. Higher red blood cell count (RBC), hemoglobin (Hb), hematocrit (Het), mean corpuscular hemoglobin (MCH), and mean corpuscular volume (MCV) among NPRC kit foxes were indicative of hemoconcentration, probably resulting from dehydration associated with low food or water intake. Kit forts from NPRC: exhibited higher blood urea nitrogen (BUN) and lower cholesterol (CHOL) levels compared to BAK kit foxes. These results may have reflected dietary differences, but they possibly indicated tissue catabolism by NPRC kit foxes due to nutritional deprivation. Other serological data also suggested nutritional stress among NPRC kit foxes. Prevalence of antibodies to canine parvovirus (CPV), canine distemper (CD), and infectious canine hepatitus (ICH) was similar between populations. Food availability for kit foxes at NPRC was relatively low during 1988-89 due to drought conditions, but food probably was not a limiting factor at BAK due to abundant water and the presence of anthropogenic foods. Urban environments may provide certain advantages for San Joaquin kit foxes and could contribute to conservation and recovery efforts. C1 USN, Petr Reserves Calif Endangered Species Program, Bakersfield, CA 93309 USA. USN, Petr Reserves Calif Endangered Species Program, Tupman, CA 93276 USA. RP Cypher, BL (reprint author), Endangered Species Recovery Program, POB 9622, Bakersfield, CA 93309 USA. EM cypher@lightspeed.net NR 42 TC 27 Z9 27 U1 2 U2 28 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0022-541X J9 J WILDLIFE MANAGE JI J. Wildl. Manage. PD JUL PY 1999 VL 63 IS 3 BP 930 EP 938 DI 10.2307/3802807 PG 9 WC Ecology; Zoology SC Environmental Sciences & Ecology; Zoology GA 216KP UT WOS:000081441500019 ER PT J AU Bennett, RH Ransom, B Kastner, M Baerwald, RJ Hulbert, MH Sawyer, WB Olsen, H Lambert, MW AF Bennett, RH Ransom, B Kastner, M Baerwald, RJ Hulbert, MH Sawyer, WB Olsen, H Lambert, MW TI Early diagenesis: impact of organic matter on mass physical properties and processes, California continental margin SO MARINE GEOLOGY LA English DT Article DE organic carbon; continental margin; sedimentation; TEM data; bacteria; geotechnical properties ID GREAT-BAHAMA-BANK; NORTHERN CALIFORNIA; CARBONATE SEDIMENT; INSITU POROSITY; PERMEABILITY; CLAY; BIOTURBATION; VARIABILITY AB High-resolution (scales of 2.5 mm to submicrometer), interdisciplinary studies of California continental slope sediments (0-80 cm) reveal the importance of marine organic material and mineralogy on mass physical properties in fine-grained sediments during very early diagenesis. The combination of organic material (greater than or equal to 2 wt.%) with smectite (greater than or equal to 5%) is associated with high depositional porosities, low effective stresses, low porosity reduction and dewatering, and the impedance of interstitial fluid flow. Living (microbiota) and nonliving (mucopolysaccharides) organic matter, affecting the physical properties, was revealed by transmission electron microscopy and carbon isotope studies. Calculations using the Redfield ratio show that sediments containing high organic carbon (greater than or equal to 5 wt.%) have 'hydrated' organic material in the pore spaces that can occupy a volume that is up to 20% of the total sediment porosity. Pore-water chemistry and X-ray diffraction show evidence of early diagenetic processes that may significantly influence sediment fabric. An important geochemical process near the sediment-water interface that affects sediment fabric is the rapid dissolution of biogenic opal. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Seaprobe, Picayune, MS 39466 USA. Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. Univ New Orleans, Dept Biol, New Orleans, LA 70148 USA. Resource Dynam, Florissant, MO 63031 USA. USN, Res Lab, Stennis Space Ctr, MS 39529 USA. Colorado Sch Mines, Div Engn, Golden, CO 80401 USA. Kansas State Univ, Dept Geol, Manhattan, KS 66506 USA. RP Bennett, RH (reprint author), Seaprobe, 501 Pine St, Picayune, MS 39466 USA. EM rbennett@datastar.net NR 44 TC 25 Z9 25 U1 2 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0025-3227 J9 MAR GEOL JI Mar. Geol. PD JUL PY 1999 VL 159 IS 1-4 BP 7 EP 34 DI 10.1016/S0025-3227(99)00003-1 PG 28 WC Geosciences, Multidisciplinary; Oceanography SC Geology; Oceanography GA 212ZP UT WOS:000081247800002 ER PT J AU Hanafi, HA Kanour, WW Beavers, GM Tetreault, GE AF Hanafi, HA Kanour, WW Beavers, GM Tetreault, GE TI Colonization and bionomics of the sandfly Phlebotomus kazeruni from Sinai, Egypt SO MEDICAL AND VETERINARY ENTOMOLOGY LA English DT Article DE Phlebotomus kazeruni; bionomics; fecundity; life table; sandfly colony; sex ratio; Sinai; Egypt ID PARAPHLEBOTOMUS KAZERUNI; LUTZOMYIA-LONGIPALPIS; SPECIES COMPOSITION; PAPATASI DIPTERA; PSYCHODIDAE AB Phlebotomus kazeruni (Diptera: Psychodidae) females were collected by light-trap in southern Sinai, Egypt, and this sandfly species was colonized for the first time as a laboratory strain, maintained by the procedures of Modi & Tesh (1983), Laboratory-reared females did not lay eggs autogenously; they blood-fed more readily (P = 0.02) on a hamster (37%) than a human (22%) during 1 h exposure. Fecundity of hamster-fed females was significantly greater than for those fed on human blood: 69.4 +/- 5.8 vs. 45.2 +/- 8.1 eggs/female from the first gonotrophic cycle. Pre-oviposition and egg incubation periods were significantly less for females fed on hamster compared with human blood, but the larval development and pupation periods were not affected by this difference in bloodmeal source. Egg to adult survival was equivalent (38%) for progeny of females blood-fed on hamster or human. The mean generation time of progeny from females fed on hamster (51.9 +/- 1.0 days) or human (53.3 +/- 1.7 days) was not significantly different. The sex ratio of adult male:female progeny was similar (P = 0.2) for both hosts: 42:58% from hamster, 46:54% from human blood-fed female parents. Evidently P. kazeruni from Sinai is sufficiently anthropophagic to be a potential vector of Leishmania from rodents to humans. C1 USN, Med Res Unit 3, Med Zool Branch, FPO, AE 09835 USA. RP Hanafi, HA (reprint author), USN, Med Res Unit 3, Med Zool Branch, Attent Code 101F,PSC 452,Box 5000, FPO, AE 09835 USA. NR 25 TC 7 Z9 11 U1 0 U2 2 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0269-283X J9 MED VET ENTOMOL JI Med. Vet. Entomol. PD JUL PY 1999 VL 13 IS 3 BP 295 EP 298 DI 10.1046/j.1365-2915.1999.00172.x PG 4 WC Entomology; Veterinary Sciences SC Entomology; Veterinary Sciences GA 241NF UT WOS:000082888900011 PM 10514056 ER PT J AU Baird, JK Hoffman, SL AF Baird, JK Hoffman, SL TI Prevention of malaria in travelers SO MEDICAL CLINICS OF NORTH AMERICA LA English DT Article ID PLASMODIUM-FALCIPARUM MALARIA; PLACEBO-CONTROLLED TRIAL; DOUBLE-BLIND; MEFLOQUINE PROPHYLAXIS; PLUS PROGUANIL; VIVAX MALARIA; DOXYCYCLINE; CHEMOPROPHYLAXIS; ANTIMALARIAL; PRIMAQUINE AB Malaria occurs throughout the tropics and represents a serious health threat to people exposed to risk of infection. Health care providers may be the only link between information for their traveling patients and that threat. The likelihood of infection can be reduced drastically by deliberate measures that minimize exposure to biting mosquitoes. However, personal protective measures alone rarely suffice where exposure to anopheline mosquitoes and infected human beings is appreciable. C1 USN, Med Res Ctr, Malaria Program, Rockville, MD USA. RP Baird, JK (reprint author), Amer Embassy, USN, Med Res Unit 2, Malaria Program, Box 3, APO, AP 96520 USA. NR 80 TC 18 Z9 18 U1 0 U2 1 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0025-7125 J9 MED CLIN N AM JI Med. Clin. N. Am. PD JUL PY 1999 VL 83 IS 4 BP 923 EP + PG 23 WC Medicine, General & Internal SC General & Internal Medicine GA 224EG UT WOS:000081884000005 PM 10453257 ER PT J AU Eierle, CC AF Eierle, CC TI May flowers SO MILITARY MEDICINE LA English DT Letter C1 USN, MC, Washington, DC USA. RP Eierle, CC (reprint author), USN, MC, Washington, DC 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 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD JUL PY 1999 VL 164 IS 7 BP IV EP V PG 2 WC Medicine, General & Internal SC General & Internal Medicine GA 215LV UT WOS:000081383900004 ER PT J AU Centeno, JA Mullick, FG Panos, RG Miller, FW Valenzuela-Espinoza, A AF Centeno, JA Mullick, FG Panos, RG Miller, FW Valenzuela-Espinoza, A TI Laser-Raman microprobe identification of inclusions in capsules associated with silicone gel breast implants SO MODERN PATHOLOGY LA English DT Article DE breast implants; capsular tissues; foreign materials; Raman microprobe; silicone gel ID CONNECTIVE-TISSUE DISEASE; INFRARED MICROSPECTROSCOPY; AUGMENTATION MAMMOPLASTY; FIBROUS CAPSULES; ANIMAL-MODEL; MICROANALYSIS; MICROSCOPY AB Raman spectroscopy (the analysis of scattered photons after excitation with a monochromatic light source) provides a nondestructive method for identifying organic and inorganic materials on the basis of the molecule's characteristic spectrum of vibrational frequencies. Although the technique has been predominantly applied in sciences other than pathology, the recent advent of high-quality microscope optics coupled to optical Raman spectrometers (a variation known as a Raman microprobe) rendered this technique amenable to applications in human pathology. In the Raman microprobe, a laser beam is focused on a spot approximately 1 mu m in diameter on the surface of the sample, e.g., tissue, and the scattered light is collected and analyzed. In this investigation, we used the Raman microprobe for the identification of foreign materials in breast implant capsular tissues. The characteristic silicone group frequencies associated with the silicon-oxygen stretch, the silicone-carbon stretch, the silicon-methyl and the methyl carbon-hydrogen stretch frequencies were used to identify polydimethylsiloxane and to define chemical differences among the various other implant-related inclusions. All of the inclusions were positively identified in a series of 44 capsules from silicone gel-filled implants: polydimethylsiloxane was found in 44 of 44 capsules surrounding silicone gel-filled implants; polyurethane was seen in 4 of 4 capsules around polyurethane foam-coated gel-filled implants; 4 of 4 capsules enveloping Dacron patch gel-filled implants revealed Dacron; and talc was identified in 8 of these 44 capsules. Raman microspectroscopy provides a rapid, accurate, and sensitive method for identifying inclusions associated with silicone and other implant materials in tissue. C1 Armed Forces Inst Pathol, Dept Environm & Toxicol Pathol, Div Environm Pathol, Washington, DC 20306 USA. USN, Med Ctr, Div Plast Surg, San Diego, CA 92152 USA. US FDA, Ctr Biol Evaluat & Res, Bethesda, MD USA. Hosp Gen Tijuana, Inst Serv Salud, Tijuana, Mexico. RP Centeno, JA (reprint author), Armed Forces Inst Pathol, Dept Environm & Toxicol Pathol, Div Environm Pathol, Washington, DC 20306 USA. OI Miller, Frederick/0000-0003-2831-9593 NR 24 TC 6 Z9 6 U1 0 U2 2 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0893-3952 J9 MODERN PATHOL JI Mod. Pathol. PD JUL PY 1999 VL 12 IS 7 BP 714 EP 721 PG 8 WC Pathology SC Pathology GA 218NY UT WOS:000081559700008 PM 10430276 ER PT J AU Giraldo, FX AF Giraldo, FX TI Trajectory calculations for spherical geodesic grids in Cartesian space SO MONTHLY WEATHER REVIEW LA English DT Article ID SEMI-LAGRANGIAN ADVECTION AB This paper shows how to obtain accurate and efficient trajectory calculations for spherical geodesic grids in Cartesian space. Determination of the departure points is essential to characteristic-based methods that trace the value of a function to the foot of the characteristics and then either integrate or interpolate at this location. In this paper, the departure points are all computed in relation to the spherical geodesic grids that are composed of a disjoint set of unstructured equilateral triangles. Interpolating and noninterpolating trajectory calculation approaches are both illustrated and the accuracy of both methods are compared. The noninterpolating method of McGregor results in the most accurate trajectories. The challenge in using McGregor's method on unstructured triangular grids lies in the computation of the derivatives required in the high-order terms of the Taylor series expansion. This paper extends McGregor's method to unstructured triangular grids by describing an accurate and efficient method for constructing the derivatives in an element by element approach typical of finite element methods. An order of accuracy analysis reveals that these numerical derivatives are second-order accurate. C1 USN, Res Lab, Monterey, CA 93943 USA. RP Giraldo, FX (reprint author), USN, Res Lab, 7 Grace Hopper Ave, Monterey, CA 93943 USA. NR 8 TC 16 Z9 16 U1 0 U2 4 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 1999 VL 127 IS 7 BP 1651 EP 1662 DI 10.1175/1520-0493(1999)127<1651:TCFSGG>2.0.CO;2 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 221VZ UT WOS:000081748900016 ER PT J AU Merzbacher, CI Barker, JG Long, JW Rolison, DR AF Merzbacher, CI Barker, JG Long, JW Rolison, DR TI The morphology of nanoscale deposits of ruthenium oxide in silica aerogels SO NANOSTRUCTURED MATERIALS LA English DT Article; Proceedings Paper CT 4th International Conference on Nanostructured Materials (NANO 98) CY JUN 14-19, 1998 CL STOCKHOLM, SWEDEN SP Royal Inst Technol, Sweden, Swedish Consortium Clusters & Ultrafine Particles, Sweden, Royal Inst Technol, Brinell Ctr, Sweden, European Consortium Nanophase Mat, Switzerland, Acta Met Inc, USA, Alps Elect Co, Japan, Canon Ctr City, Sweden, Carl Tryggers Stiftelse, Sweden, Elsevier Sci Inc, Switzerland, Finnair, Finland, Off Naval Res ONR, USA, European Res Off US Army, USARDSD-UK, Swedish Nat Sci Res Council, NFR, Sweden, Swedish Res Council Engn Sci, TFR, Sweden, Swedish Nat Board Ind & Tech Dev (NUTEK), Swedish Royal Acad Sci, Nobel Comm Phys, Sweden, Swedish Royal Acad Sci, Nobel comm Chem, Sweden AB Ruthenium oxide was deposited an the internal surfaces of silica aerogel by solution impregnation of a Ru(III)tris-acetylacetonate solution followed by reduction and oxidation. The structure of the Ru phase was determined by contrast-matching SANS, which allows independent collection of scattered intensity from SiO2 and Ru oxide components of composite samples. The structure of the Ru oxide deposit depends strongly on the oxidation temperature and very little on the reduction temperature. The Ru oxide forms particles, rather than a conformal layer, which coarsen from a few nanometers after oxidation at room temperature to several tens of nm after oxidation at 250 degrees C. (C) 1999 Acta Metallurgica Inc. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Merzbacher, CI (reprint author), USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. NR 5 TC 11 Z9 11 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0965-9773 J9 NANOSTRUCT MATER JI Nanostruct. Mater. PD JUL PY 1999 VL 12 IS 1-4 SI SI BP 551 EP 554 DI 10.1016/S0965-9773(99)00181-6 PN A PG 4 WC Materials Science, Multidisciplinary SC Materials Science GA 224RM UT WOS:000081912100128 ER PT J AU Martinez-Miranda, LJ Li, YQ Chow, GM Kurihara, LK AF Martinez-Miranda, LJ Li, YQ Chow, GM Kurihara, LK TI A depth profile study of the structure and strain distribution in chemically grown Cu films on AlN SO NANOSTRUCTURED MATERIALS LA English DT Article; Proceedings Paper CT 4th International Conference on Nanostructured Materials (NANO 98) CY JUN 14-19, 1998 CL STOCKHOLM, SWEDEN SP Royal Inst Technol, Sweden, Swedish Consortium Clusters & Ultrafine Particles, Sweden, Royal Inst Technol, Brinell Ctr, Sweden, European Consortium Nanophase Mat, Switzerland, Acta Met Inc, USA, Alps Elect Co, Japan, Canon Ctr City, Sweden, Carl Tryggers Stiftelse, Sweden, Elsevier Sci Inc, Switzerland, Finnair, Finland, Off Naval Res ONR, USA, European Res Off US Army, USARDSD-UK, Swedish Nat Sci Res Council, NFR, Sweden, Swedish Res Council Engn Sci, TFR, Sweden, Swedish Nat Board Ind & Tech Dev (NUTEK), Swedish Royal Acad Sci, Nobel Comm Phys, Sweden, Swedish Royal Acad Sci, Nobel comm Chem, Sweden ID POLYOL PROCESS AB We have studied Cu coatings grown on AIN substrates via a polyol deposition method using grazing incidence X-ray (GIXS) techniques and small angle scattering techniques to determine the dependence of film structure on depth as well as the presence of nanometer size structures in the films. Small angle measurements indicate the presence of ordered structures in the order of 4 nm close to the surface of the films. Depth studies using different X-ray energies in combination with the GIXS technique suggest the first 20 to 60 nm of the film correspond to a textured region, with strains ranging between +0.1% to -0.6%. The azimuthal ordering in the plane of the films depends on the sample deposition time and the substrate orientation. (C) 1999 Acta Metallurgica Inc. C1 Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. USN, Res Lab, Washington, DC 20375 USA. Potomac Res Int, Fairfax, VA 22030 USA. RP Martinez-Miranda, LJ (reprint author), Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. NR 4 TC 7 Z9 7 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0965-9773 J9 NANOSTRUCT MATER JI Nanostruct. Mater. PD JUL PY 1999 VL 12 IS 5-8 SI SI BP 653 EP 656 DI 10.1016/S0965-9773(99)00209-3 PN B PG 4 WC Materials Science, Multidisciplinary SC Materials Science GA 224RN UT WOS:000081912200015 ER PT J AU Provenzano, V Valiev, R Rickerby, DG Valdre, G AF Provenzano, V Valiev, R Rickerby, DG Valdre, G TI Mechanical properties of nanostructured chromium SO NANOSTRUCTURED MATERIALS LA English DT Article; Proceedings Paper CT 4th International Conference on Nanostructured Materials (NANO 98) CY JUN 14-19, 1998 CL STOCKHOLM, SWEDEN SP Royal Inst Technol, Sweden, Swedish Consortium Clusters & Ultrafine Particles, Sweden, Royal Inst Technol, Brinell Ctr, Sweden, European Consortium Nanophase Mat, Switzerland, Acta Met Inc, USA, Alps Elect Co, Japan, Canon Ctr City, Sweden, Carl Tryggers Stiftelse, Sweden, Elsevier Sci Inc, Switzerland, Finnair, Finland, Off Naval Res ONR, USA, European Res Off US Army, USARDSD-UK, Swedish Nat Sci Res Council, NFR, Sweden, Swedish Res Council Engn Sci, TFR, Sweden, Swedish Nat Board Ind & Tech Dev (NUTEK), Swedish Royal Acad Sci, Nobel Comm Phys, Sweden, Swedish Royal Acad Sci, Nobel comm Chem, Sweden ID GRAIN SIZES; METALS AB In this paper we present some initial results on pure chromium whose grain structure was refined by severe plastic deformation processing. These results include the microstructural features and the corresponding mechanical properties as a function of severe plastic deformation processing and annealing treatment. They show that severe plastic deformation is quite effective in reducing the grain size down to nanoscale dimensions with an attendant large increase in the hardness value; the hardness data is consistent with Hall-Fetch strengthening. The annealing treatment demonstrated that the nanoscale microstructure is retained up to 400 degrees C. Further, the decrease in the hardness value with increasing annealing temperature is quire gradual lip to 900 degrees C, suggesting that the microstructure of pure chromium, resulting from the severe deformation is not too unstable, but, it coarsens gradually with increasing temperature. Therefore, in the chromium alloys the deformed microstructure is expected to be even more stable due to the beneficial effect of the alloying additions in pinning the grain boundaries. (C) 1999 Acta Metallurgica Inc. C1 USN, Res Lab, Washington, DC 20375 USA. Ufa Tech Univ, Inst Mat Phys, Ufa, Russia. Commiss European Communities, Joint Res Ctr, Inst Adv Mat, I-21020 Ispra, VA, Italy. Univ Bologna, Dept Phys, I-40126 Bologna, Italy. RP Provenzano, V (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 11 TC 13 Z9 13 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0965-9773 J9 NANOSTRUCT MATER JI Nanostruct. Mater. PD JUL PY 1999 VL 12 IS 5-8 SI SI BP 1103 EP 1108 DI 10.1016/S0965-9773(99)00307-4 PN B PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 224RN UT WOS:000081912200113 ER PT J AU Yankaskas, KD Shaw, MF AF Yankaskas, KD Shaw, MF TI Landing on the roof: CVN noise SO NAVAL ENGINEERS JOURNAL LA English DT Article AB There has been renewed interest in the human effects of excessive intermittent airborne noise occurring on the 03 Level (Gallery Deck) and on the Flight Deck during aircraft launch and recovery operations ("Flight Ops") aboard U.S. Navy aircraft carriers. High noise levels cause crew fatigue, lost work hours, high crew turnover, safety problems, and worst case, hearing damage or loss of life. The cost of this problem can be quantified as part of the Total Ownership Cost of the ship by taking into account such factors as the cost of veterans' hearing compensation, crew retention bonuses, and crew turnover. This interest has lead to at-sea measurements of intermittent noise levels during flight operations on two operational aircraft carriers. This data provides the first detailed, systematic quantification of sound pressure levels, noise frequency content, noise time duration and frequency of events. The classic acoustic source/path/receiver approach was used to investigate noise sources and paths associated with the transmission of aircraft and machinery noise. Solutions take a total ship engineering approach, combining Total Ownership Cost, Human Engineering, and industrial partnerships to develop cost effective solutions to mitigate noise associated with flight operations. C1 USN, Sea Syst Command, Ship Signatures Off, Surface Ship Acoust, Washington, DC USA. RP Yankaskas, KD (reprint author), USN, Sea Syst Command, Ship Signatures Off, Surface Ship Acoust, Washington, DC USA. NR 18 TC 2 Z9 2 U1 1 U2 1 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 USA SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD JUL PY 1999 VL 111 IS 4 BP 23 EP 34 PG 12 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA 216FJ UT WOS:000081430500009 ER PT J AU Breslin, DA AF Breslin, DA TI A history of the navy's strategic reserve of ozone-depleting substances SO NAVAL ENGINEERS JOURNAL LA English DT Article AB The domestic production of the most powerful Ozone-Depleting Substances (ODSs) has permanently ceased and the abundant supplies of a number of refrigerants, fire-fighting agents, and solvents, once taken for granted, are now a thing of the past. The Navy has adopted a successful strategy for addressing the threat posed by the unavailability of ODSs and that strategy includes relying on a strategic reserve of ODSs. Considering that the strategic reserve will play a critical role in sustained Fleet operations well into the next century, it is important to record the history of the reserve and to document lessons learned in order to educate future generations that may be faced with similar challenges. This paper documents the history of the Navy's effort to define, establish, and monitor a reserve designed to support Fleet operations until the middle of the next century. C1 USN, Ctr Surface Warfare, Tech Operat, Washington, DC USA. RP Breslin, DA (reprint author), USN, Ctr Surface Warfare, Tech Operat, Washington, DC USA. NR 34 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 USA SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD JUL PY 1999 VL 111 IS 4 BP 69 EP 76 PG 8 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA 216FJ UT WOS:000081430500013 ER PT J AU Daniel, JC Olesniewicz, MH Reeves, DL Tam, D Bleiberg, J Thatcher, R Salazar, A AF Daniel, JC Olesniewicz, MH Reeves, DL Tam, D Bleiberg, J Thatcher, R Salazar, A TI Repeated measures of cognitive processing efficiency in adolescent athletes: Implications for monitoring recovery from concussion SO NEUROPSYCHIATRY NEUROPSYCHOLOGY AND BEHAVIORAL NEUROLOGY LA English DT Article ID MILD HEAD-INJURY; NEUROPSYCHOLOGICAL ASSESSMENT AB Objective: The objective of this study was to determine whether an adolescent athlete, in the absence of concussion, would be expected to show an improvement in cognitive function during the course of a high school football season. Background: At least 60,000 American high school football players suffer cerebral concussion every year, and symptoms may persist for 4 or more years in as many as 24%. Method: 34 members of a cohort of healthy athletes, aged 13-18, were administered a computerized neuropsychologic test battery from the Automated Neuropsychological Assessment Metrics (ANAM) before and after the 1997 high school football season, with a mean interval of 16.1 (range 12.3-20.4) weeks between tests. Preseason and postseason scores on eight tests were compared, with significance determined by paired t-test. For those tests in which an improvement was noted, one-way analysis of variance and Wilcoxon tests were used with both preseason and postseason data to determine if there was a measurable difference in cognitive processing efficiency between older and younger subjects. Results: Improvements in processing efficiency (p < 0.001) were noted on tests designed to measure visual scanning and sustained attention (CDS), immediate recall (CDI), and short-term memory (CDD). Older subjects generally performed better on each of these tests, though the difference was significant in only one case (postseason CDI, 17-18 year olds vs. 13-14 year olds, Wilcoxon, p = 0.043). Conclusions: Our findings suggest that ANAM is sensitive to differences and improvements in cognitive function during a 4 month interval in adolescence. They also suggest that using "return to baseline" cognitive function as the criterion for evidence of recovery from concussion may be insufficient, especially when the baseline measurement was obtained 4 or more months prior to the date of "full recovery." C1 USN, Med Ctr, Med Editing Div, Dept Clin Res, San Diego, CA 92134 USA. USN, Med Ctr, Dept Pediat, Adolescent Med Div, San Diego, CA 92134 USA. Uniformed Serv Univ Hlth Sci, Dept Family Med, Bethesda, MD 20814 USA. Univ Calif San Diego, Dept Family & Prevent Med, Sch Med, San Diego, CA 92103 USA. Henry M Jackson Fdn, Rockville, MD USA. USN, Med Ctr, Dept Pediat, Child Neurol Div, San Diego, CA 92152 USA. Natl Rehabil Hosp, Psychol Serv, Washington, DC USA. Vet Affairs Med Ctr, Med Res & Dev Serv, Bay Pines, FL USA. Walter Reed Army Med Ctr, Def & Vet Head Injury Program, Washington, DC 20307 USA. RP Daniel, JC (reprint author), USN, Med Ctr, Med Editing Div, Dept Clin Res, Code AVA,34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 16 TC 44 Z9 46 U1 6 U2 10 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0894-878X J9 NEUROPSY NEUROPSY BE JI Neuropsychiatr. Neuropsychol. Behav. Neurol. PD JUL PY 1999 VL 12 IS 3 BP 167 EP 169 PG 3 WC Clinical Neurology; Psychiatry; Psychology SC Neurosciences & Neurology; Psychiatry; Psychology GA 224LF UT WOS:000081900000005 PM 10456800 ER PT J AU Dubik, M AF Dubik, M TI Low-fat milk SO PEDIATRIC ANNALS LA English DT Letter C1 Natl Naval Med Ctr, Portsmouth, VA 23708 USA. RP Dubik, M (reprint author), Natl Naval Med Ctr, Portsmouth, VA 23708 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU SLACK INC PI THOROFARE PA 6900 GROVE RD, THOROFARE, NJ 08086 USA SN 0090-4481 J9 PEDIATR ANN JI Pediatr. Annu. PD JUL PY 1999 VL 28 IS 7 BP 411 EP 412 PG 2 WC Pediatrics SC Pediatrics GA 215ME UT WOS:000081384800005 PM 10884849 ER PT J AU Shope, TR Bradley, BJ Taras, HL AF Shope, TR Bradley, BJ Taras, HL TI A block rotation in community pediatrics SO PEDIATRICS LA English DT Article DE block rotation; community pediatrics ID PRIMARY-CARE; RESIDENCY PROGRAM; EDUCATION AB Objectives. To develop, implement, and evaluate a 1-month block rotation in community pediatrics. Interventions. Faculty from University of California San Diego and Naval Medical Center San Diego developed a combined and integrated curriculum for second-year residents in community pediatrics. Resident activities included structured site visits to schools, day care centers, and community organizations that participate in child health promotion, advocacy, public health, and prevention activities. Resident school consultation and child advocacy projects were established and mentored during the block rotation. Evaluation. Formative evaluation of the program by residents was used to shape the program design. Residents' self-perceived competence in eight areas of community pediatrics was measured with questionnaires administered before and after completion of the rotation. Resident involvement in school consultation and child advocacy projects was assessed in a cross-sectional survey. Results Twenty-three residents completed the rotation during the 1-year study period. Statistically significant improvements in self-perceived competence were noted in all eight areas of community pediatrics. Among residents who were at least 3 months beyond the rotation completion date, 55% (11/20) reported continued involvement with their school consultation or child advocacy project, and 25% (5/20) reported this involvement to be on a quarterly to monthly basis. Conclusions. Two institutions successfully implemented and integrated a block rotation in community pediatrics. Positive short-term improvements were noted in resident self-perceived competence in community pediatrics. C1 Univ Calif San Diego, Div Community Pediat, Dept Pediat, La Jolla, CA 92093 USA. USN, Med Ctr, Dept Pediat, San Diego, CA 92152 USA. USN, Med Ctr, Dept Clin Res, San Diego, CA 92152 USA. RP Taras, HL (reprint author), Univ Calif San Diego, Div Community Pediat, Dept Pediat, 9500 Gilman Dr, La Jolla, CA 92093 USA. NR 19 TC 26 Z9 26 U1 1 U2 2 PU AMER ACAD PEDIATRICS PI ELK GROVE VILLAGE PA 141 NORTH-WEST POINT BLVD,, ELK GROVE VILLAGE, IL 60007-1098 USA SN 0031-4005 J9 PEDIATRICS JI Pediatrics PD JUL PY 1999 VL 104 IS 1 SU S BP 143 EP 147 PG 5 WC Pediatrics SC Pediatrics GA 213LN UT WOS:000081274500003 PM 10390280 ER PT J AU Clemens, J Abu Elyazeed, R Rao, M Savarino, S Morsy, BZ Kim, Y Wierzba, T Naficy, A Lee, YJ AF Clemens, J Abu Elyazeed, R Rao, M Savarino, S Morsy, BZ Kim, Y Wierzba, T Naficy, A Lee, YJ TI Early initiation of breastfeeding and the risk of infant diarrhea in rural Egypt SO PEDIATRICS LA English DT Article DE breastfeeding; colostrum; diarrhea; Egypt ID PERSISTENT DIARRHEA; GUINEA-BISSAU; CHILDREN AB Background. Initiation of breastfeeding shortly after delivery may enhance breastfeeding's protective effect against diarrhea because of the protective properties of human colostrum contained in early breast milk. Objective. To evaluate whether initiation of breast-feeding within the first 3 days of life, when breast milk contains colostrum, was associated with a lower rate of diarrhea in rural Egyptian infants during the first 6 months of life. Methods. Infants initially breastfed (n = 198) were monitored prospectively with twice-weekly home visits to ascertain dietary practices and diarrheal illnesses. Results. The burden of diarrhea during the first 6 months of life in the cohort was high: seven episodes per child-year of follow-up. Only 151 (76%) infants initiated breastfeeding during the first 3 days of life ("early initiation"). Infants in whom breastfeeding was initiated early had a 26% (95% CI: 2%,44%) lower rate of diarrhea than those initiated late. The protective association between early initiation and diarrhea was independent of the pattern of postinitiation dietary practices and was evident throughout the first 6 months of life. Conclusions. Early initiation of breastfeeding was associated with a marked reduction of the rate of diarrhea throughout the first 6 months of life, possibly because of the salutary effects of human colostrum. These data highlight the need for interventions to encourage early initiation of breastfeeding in less developed settings. C1 NICHHD, Div Epidemiol Stat & Prevent Res, Bethesda, MD 20892 USA. USN, Med Res Unit 3, Cairo, Egypt. Minist Hlth & Populat, Abu Homos, Egypt. RP Clemens, J (reprint author), NICHHD, Div Epidemiol Stat & Prevent Res, Bldg 6100,Rm 7B03, Bethesda, MD 20892 USA. RI Savarino, Stephen/A-8030-2011 FU NICHD NIH HHS [Y1-HD-0026-01] NR 17 TC 30 Z9 31 U1 0 U2 1 PU AMER ACAD PEDIATRICS PI ELK GROVE VILLAGE PA 141 NORTH-WEST POINT BLVD,, ELK GROVE VILLAGE, IL 60007-1098 USA SN 0031-4005 J9 PEDIATRICS JI Pediatrics PD JUL PY 1999 VL 104 IS 1 BP art. no. EP e3 DI 10.1542/peds.104.1.e3 PG 5 WC Pediatrics SC Pediatrics GA 213EC UT WOS:000081258700018 PM 10390289 ER PT J AU Mazin, II AF Mazin, II TI Theoretical possibilities for superconductivity in PrBa2Cu3O7 SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE; Y1-XPRXBA2CU3O7; PR AB Recent reports about observations of superconductivity in PrBa2Cu3O7 raise a number of questions. (i) Of the various theories striving to explain the T-c suppression in PrxY1 - xBa2Cu3O7, are there any compatible with possible superconductivity in stoichiometric PrBa2Cu3O7? (ii) If this superconductivity is not an experimental artifact, are the superconducting carriers (holes) of the same character as in the other high-T-c, cuprates, or do they represent another electronic subsystem? (iii) Is the underlying mechanism the same as in other high-T-c superconductors? I present an answer to the first two questions, leaving the last one open. [S0163-1829(99)13925-0]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Mazin, II (reprint author), USN, Res Lab, Code 6391,4555 Overlook Ave SW, Washington, DC 20375 USA. RI Mazin, Igor/B-6576-2008 NR 15 TC 12 Z9 12 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JUL 1 PY 1999 VL 60 IS 1 BP 92 EP 95 DI 10.1103/PhysRevB.60.92 PG 4 WC Physics, Condensed Matter SC Physics GA 218KE UT WOS:000081551100024 ER PT J AU Hayn, R Rosner, H Yushankhai, VY Haffner, S Durr, C Knupfer, M Krabbes, G Golden, MS Fink, J Eschrig, H Singh, DJ Hien, NT Menovsky, AA Jung, C Reichardt, G AF Hayn, R Rosner, H Yushankhai, VY Haffner, S Durr, C Knupfer, M Krabbes, G Golden, MS Fink, J Eschrig, H Singh, DJ Hien, NT Menovsky, AA Jung, C Reichardt, G TI Analysis of the valence-band photoemission spectrum of Sr2CuO2Cl2 along the high-symmetry directions SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE; HOLE; SUPERCONDUCTORS; PARAMETERS; ANTIFERROMAGNET; BA2CU3O4CL2; LA2CUO4; SYSTEMS; OXYGEN; PLANE AB Band structure calculations have been used to identify the different bands contributing to the polarization-dependent photoemission spectra of the undoped model cuprate Sr2CuO2Cl2 at the high-symmetry points of the CuO2 plane Gamma, (pi,/a,0) and (pi/a, pi/a) and along the high-symmetry directions Gamma-(pi/a, pi/a) and Gamma - ( pi/a, 0). Results from calculations within the local density approximation (LDA) have been compared with calculations taking into account the strong electron correlations by LDA+U, with the result that the experimental order of energy levels at the high-symmetry points is better described by the LDA+U calculation than by the simple LDA. All the main peaks in the photoemission spectra at the high symmetry points could be assigned to different Cu 3d and O 2p orbitalis which we have classified according to their point symmetries. The dispersions along the high-symmetry directions were compared with an 11-band tight-binding model which was fitted both to the LDA+U band structure calculation and the angle-resolved photoemission data. The mean field treatment successfully describes the oxygen derived bands but shows discrepancies for the copper ones. [S0163-1829(99)01925-6]. C1 TU Dresden, Inst Theoret Phys, D-01062 Dresden, Germany. Joint Inst Nucl Res, Dubna 141980, Moscow Region, Russia. Inst Solid State & Mat Res IFW Dresden, D-01171 Dresden, Germany. USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. Univ Amsterdam, Van der Waals Zeeman Lab, NL-1018 XE Amsterdam, Netherlands. BESSY GmbH, D-14195 Berlin, Germany. RP Hayn, R (reprint author), TU Dresden, Inst Theoret Phys, D-01062 Dresden, Germany. RI Golden, Mark/D-3469-2011; Singh, David/I-2416-2012; Fink, Joerg/A-6003-2012 NR 32 TC 24 Z9 24 U1 0 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JUL 1 PY 1999 VL 60 IS 1 BP 645 EP 658 DI 10.1103/PhysRevB.60.645 PG 14 WC Physics, Condensed Matter SC Physics GA 218KE UT WOS:000081551100089 ER PT J AU Streitz, FH Mintmire, JW AF Streitz, FH Mintmire, JW TI Energetics of aluminum vacancies in gamma alumina SO PHYSICAL REVIEW B LA English DT Article AB We present results for total-energy simulations of the energetics of vacancy occupation of gamma alumina using an empirical potential that allows the ionic valence to vary according to the local environment and includes Coulombic electrostatic interactions among the anions and cations. Our model predicts that although the minimum enthalpy configuration has all aluminum vacancies from the spinel structure in octahedral sites, the energetic cost of a modest fraction of tetrahedral sites is small. We furthermore use-our model to explain the differences between previously reported simulations on this question in terms of their constraints on structural and charge relaxation. C1 Auburn Univ, Dept Phys, Auburn, AL 36849 USA. USN, Res Lab, Washington, DC 20375 USA. RP Streitz, FH (reprint author), Auburn Univ, Dept Phys, Auburn, AL 36849 USA. OI Mintmire, John/0000-0002-6551-0349 NR 13 TC 44 Z9 45 U1 1 U2 9 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JUL 1 PY 1999 VL 60 IS 2 BP 773 EP 777 DI 10.1103/PhysRevB.60.773 PG 5 WC Physics, Condensed Matter SC Physics GA 218QU UT WOS:000081563800014 ER PT J AU Jaime, M Lin, P Chun, SH Salamon, MB Dorsey, P Rubinstein, M AF Jaime, M Lin, P Chun, SH Salamon, MB Dorsey, P Rubinstein, M TI Coexistence of localized and itinerant carriers near T-C in calcium-doped manganites SO PHYSICAL REVIEW B LA English DT Article ID COLOSSAL-MAGNETORESISTANCE; FERROMAGNETIC TRANSITION; POLARON CROSSOVER; PEROVSKITE; LA1-XCAXMNO3; RESISTIVITY; TRANSPORT; LA0.67CA0.33MNO3; LA2/3CA1/3MNO3; LA1-XSRXMNO3 AB We explore the possibility that polaronic distortions in the paramagnetic phase of La0.67Ca0.33MnO3 manganites persist in the ferromagnetic phase by considering the observed electrical resistivity to arise from coexisting field- and temperature-dependent polaronic and band-electron fractions. We use an effective medium approach to compute the total resistivity of the two-component system, and find that a limit with low percolation threshold explains the data rather well. To test the validity of this model, we apply it to the thermoelectric coefficient. We propose a plausible mean-field model that reproduces the essential features of a microscopic model and provides a comparison with the experimental mixing fraction, as well as the magnetization and magnetic susceptibility. C1 Univ Illinois, Mat Res Lab, Urbana, IL 61801 USA. USN, Res Lab, Washington, DC 20375 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. RP Jaime, M (reprint author), Univ Calif Los Alamos Natl Lab, MSK764, Los Alamos, NM 87545 USA. RI Jaime, Marcelo/F-3791-2015; OI Jaime, Marcelo/0000-0001-5360-5220; Chun, Seung-Hyun/0000-0001-8397-4481 NR 37 TC 161 Z9 163 U1 1 U2 13 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JUL 1 PY 1999 VL 60 IS 2 BP 1028 EP 1032 DI 10.1103/PhysRevB.60.1028 PG 5 WC Physics, Condensed Matter SC Physics GA 218QU UT WOS:000081563800047 ER PT J AU McDevitt, ER Roberts, WO AF McDevitt, ER Roberts, WO TI Dorsal dislocations of the MCP joint - Assessment and closed reduction SO PHYSICIAN AND SPORTSMEDICINE LA English DT Article C1 USN Acad, Annapolis, MD 21402 USA. MinnHlth SportsCare, White Bear Lake, MN USA. RP McDevitt, ER (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU MCGRAW HILL HEALTHCARE PUBLICATIONS PI MINNEAPOLIS PA 4530 WEST 77TH ST, MINNEAPOLIS, MN 55435-5000 USA SN 0091-3847 J9 PHYSICIAN SPORTSMED JI Physician Sportsmed. PD JUL PY 1999 VL 27 IS 7 BP 75 EP 76 PG 2 WC Primary Health Care; Orthopedics; Sport Sciences SC General & Internal Medicine; Orthopedics; Sport Sciences GA 212DX UT WOS:000081202600006 PM 20086734 ER PT J AU Calame, JP Danly, BG Garven, M AF Calame, JP Danly, BG Garven, M TI Measurements of intrinsic shot noise in a 35 GHz gyroklystron SO PHYSICS OF PLASMAS LA English DT Article ID BAND GYROKLYSTRON; AMPLIFIER AB Experimental measurements of electron beam shot noise in a 35 GHz, 225 kW, three-cavity gyroklystron have been obtained from both the input and output cavities. This intrinsic noise was studied in the absence of an applied carrier (i.e., at zero drive power). The spectrum of the noise emitted by the input cavity is found to have a Lorentzian shape, with peak noise power densities from the input cavity typically reaching 6.3x10(-15) W/Hz (-112 dBm/Hz), and typical 3 dB bandwidths of 160 MHz. The output cavity noise spectrum is found to be equal to the input cavity noise spectrum multiplied by the measured linear frequency response of the gyroklystron. The measured noise levels at the input cavity are 0-5 dB lower than theoretical predictions for shot noise unaltered by collective effects. Furthermore, the input cavity noise power exhibits complex variations as a function of beam current, beam velocity ratio, and circuit magnetic field that are not predicted by present theory. Noise-to-carrier ratios expected in the input cavity during full power amplifier operation are inferred from the noise measurements and known values of drive power required to saturate the gyroklystron. The noise-to-carrier ratio, with typical values of -90 to -80 dBc, is found to be a strong function of the operating parameters. (C) 1999 American Institute of Physics. [S1070-664X(99)04207-X]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Calame, JP (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 29 TC 12 Z9 13 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JUL PY 1999 VL 6 IS 7 BP 2914 EP 2925 DI 10.1063/1.873249 PG 12 WC Physics, Fluids & Plasmas SC Physics GA 208LV UT WOS:000080993600033 ER PT J AU Holt, DB Farmer, BL AF Holt, DB Farmer, BL TI Modeling of helix reversal defects in polytetrafluoroethylene II. Molecular dynamics simulations SO POLYMER LA English DT Article; Proceedings Paper CT Symposium on 20-20 Vision of Polymer Science - The Next 2 Decades CY MAY 13-15, 1999 CL UNIV AKRON, AKRON, OHIO HO UNIV AKRON DE polytetrafluoroethylene; helix reversal defects; molecular dynamics ID LOW-TEMPERATURE PHASE(II); CRYSTAL-STRUCTURE; ENERGY CALCULATIONS; POLY(TETRAFLUOROETHYLENE); TRANSITIONS AB Molecular mechanics and dynamics simulations have been utili zed to probe the nature of helix reversal activity in polytetrafluoroethylene (PTFE). The results of the simulations indicated that helix reversals do form and migrate in PTFE crystals. At low and intermediate temperatures, the most important defect structure was a helix reversal band: two helix reversals which bracket a small chain segment having the opposite helical sense from the parent molecule. The size of this reversal band defect was equal to approximately half of the helical repeat unit in the low and intermediate temperature phases. In the high temperature phase where intermolecular effects are diminished, a wider distribution of reversal band sizes was observed during the simulations. The impact of helix reversal activity on rotational disorder was also examined. In addition to the rotational disorder created by the presence and motion of helix reversals, a mechanism was identified by which significant reorientation of a chain segment (having the same helical sense as the host chain) about the molecular axis can occur when it is bracketed by two helix reversal bands. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 USAF, Res Lab, AFRL, MLBP, Wright Patterson AFB, OH 45433 USA. USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. RP Farmer, BL (reprint author), USAF, Res Lab, AFRL, MLBP, 2941 P St,Suite 1, Wright Patterson AFB, OH 45433 USA. NR 17 TC 16 Z9 16 U1 0 U2 4 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0032-3861 J9 POLYMER JI Polymer PD JUL PY 1999 VL 40 IS 16 BP 4673 EP 4684 DI 10.1016/S0032-3861(99)00076-2 PG 12 WC Polymer Science SC Polymer Science GA 189LE UT WOS:000079905600027 ER PT J AU Straube, WL Jones-Meehan, J Pritchard, PH Jones, WR AF Straube, WL Jones-Meehan, J Pritchard, PH Jones, WR TI Bench-scale optimization of bioaugmentation strategies for treatment of soils contaminated with high molecular weight polyaromatic hydrocarbons SO RESOURCES CONSERVATION AND RECYCLING LA English DT Article DE bioaugmentation; biodegradation; polyaromatic hydrocarbons ID POLYCYCLIC AROMATIC-HYDROCARBONS; BIOREMEDIATION; DEGRADATION; SURFACTANTS AB The chemical composition of crude oil and even of refined petroleum includes hundreds of different alkanes and aromatic hydrocarbons. Among these are the polycyclic aromatic hydrocarbons (PAHs), which are known carcinogens and widespread environmental contaminants. Some compounds present in hydrocarbon-contaminated soils are rapidly removed by the activities of autochthonous bacterial populations while other PAHs, especially those with four or more fused aromatic rings, are refractory to biodegradation. The persistence of high molecular weight polyaromatic hydrocarbons (hPAHs) in soils implies either that their low solubility renders them poorly available to bacteria, or that autochthonous bacteria do not contain the metabolic or co-metabolic pathways required for their degradation or both. The rate and extent of PAH degradation in contaminated soil is not always predictable for standard biological treatment strategies. This study examines a matrix of treatments suitable for land farming in order to identify those that maximize the removal of hPAHs. The treatments include those intended to increase the bioavailability of hPAH, such as additions of biosurfactant-producing bacteria (i.e. Pseudomonas aeruginosa #64) and addition of light oils, as well as treatments intended to increase the metabolic potential of the bacterial community. The latter includes the addition of inorganic nutrients and bacterial strains capable of degrading hPAHs co-metabolically (i.e. Sphingomonas paucimobilis EPA 505). The efficacy of immobilizing PAM-degrading bacteria on vermiculite is also considered, as will be the monitoring of leachate for biodegradation of PAHs in a simulated land farming operation. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Maryland, Inst Biotechnol, Ctr Marine Biotechnol, Baltimore, MD 21202 USA. USN, Res Lab, Environm Qual Sci Sect, Washington, DC 20375 USA. RP Jones, WR (reprint author), Univ Maryland, Inst Biotechnol, Ctr Marine Biotechnol, 701 E Pratt St, Baltimore, MD 21202 USA. NR 17 TC 28 Z9 31 U1 2 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-3449 J9 RESOUR CONSERV RECY JI Resour. Conserv. Recycl. PD JUL PY 1999 VL 27 IS 1-2 BP 27 EP 37 DI 10.1016/S0921-3449(98)00083-4 PG 11 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 211CJ UT WOS:000081142100005 ER PT J AU Michaelis, JT AF Michaelis, JT TI US Navy's AUTEC ranges SO SEA TECHNOLOGY LA English DT Article C1 USN, Undersea Warfare Ctr, Atlantic Undersea Test & Evaluat Ctr Detachment, W Palm Beach, FL USA. RP Michaelis, JT (reprint author), USN, Undersea Warfare Ctr, Atlantic Undersea Test & Evaluat Ctr Detachment, W Palm Beach, FL USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU COMPASS PUBL INC PI ARLINGTON PA SUITE 1000 1117 N 19 ST, ARLINGTON, VA 22209 USA SN 0093-3651 J9 SEA TECHNOL JI Sea Technol. PD JUL PY 1999 VL 40 IS 7 BP 57 EP 59 PG 3 WC Engineering, Ocean SC Engineering GA 222NP UT WOS:000081791900012 ER PT J AU Aziz, AM Tummala, M Cristi, R AF Aziz, AM Tummala, M Cristi, R TI Fuzzy logic data correlation approach in multisensor-multitarget tracking systems SO SIGNAL PROCESSING LA English DT Article DE data correlation; data association; tracking systems; data fusion ID DATA ASSOCIATION; EFFICIENT ALGORITHM; FUSION AB In this paper, a fuzzy logic data correlation approach for multisensor-multitarget tracking is proposed. This fuzzy correlation approach is developed based on fuzzy clustering means algorithm. The proposed approach is applied to a two- and a four-dimensional multisensor-multitarget tracking system using Monte Carlo simulations. Fuzzy system performance evaluation is presented to demonstrate the efficiency of the new approach. The computational complexity of this approach is also analyzed and compared to that of conventional fuzzy logic data association methods. Considerable improvement in terms of computational complexity and performance is achieved. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. RP Aziz, AM (reprint author), USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. NR 41 TC 30 Z9 39 U1 3 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0165-1684 J9 SIGNAL PROCESS JI Signal Process. PD JUL PY 1999 VL 76 IS 2 BP 195 EP 209 DI 10.1016/S0165-1684(99)00008-0 PG 15 WC Engineering, Electrical & Electronic SC Engineering GA 204KT UT WOS:000080764000007 ER PT J AU Appleby, D AF Appleby, D TI Authors of the Middle-Ages: Historical and religious writers of the Latin West SO SPECULUM-A JOURNAL OF MEDIEVAL STUDIES LA English DT Book Review C1 USN Acad, Annapolis, MD 21402 USA. RP Appleby, D (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU MEDIEVAL ACAD OF AMER PI CAMBRIDGE PA 1430 MASSACHUSETTS AVE, CAMBRIDGE, MA 02138 USA SN 0038-7134 J9 SPECULUM JI Speculum-J. Mediev. Stud. PD JUL PY 1999 VL 74 IS 3 BP 751 EP 752 DI 10.2307/2886800 PG 2 WC Medieval & Renaissance Studies SC Arts & Humanities - Other Topics GA 251QQ UT WOS:000083456700043 ER PT J AU Saylor, JR AF Saylor, JR TI The role of capillary waves in oceanic air/water gas exchange SO TELLUS SERIES B-CHEMICAL AND PHYSICAL METEOROLOGY LA English DT Article ID FARADAY WAVES; SURFACE-WAVES; MASS-TRANSPORT; NUMBER SPECTRA; WATER-WAVES; WIND; TUNNEL AB Recent experiments have demonstrated that millimeter-scale capillary waves can enhance the transport of CO2 by almost 2 orders of magnitude for moderate wave slopes. These results are used to create a model for the relative contribution of capillary waves to the gas exchange coefficient. The model input is wind speed u, and the output is K-f the fractional contribution of a specific range of capillary waves to the total gas exchange coefficient. Wind speed data, obtained via satellite, are used as the model input to obtain globally averaged values for K-f. In spite of the enhancing effect which capillary waves provide in the laboratory, the maximum value of K-f predicted by the model is less than 10%, and global averages are less than 4%. The small values of K-f are primarily due to the small wave energies predicted by existing wave height spectra in the high wave number regime. The uncertainty in existing wave height spectra, and the importance of experimental validation of the high wave number regime is discussed. Some interesting aspects of capillary wave gas exchange are also expanded upon. Among these are the demonstration of a linear relationship between the capillary wave gas exchange coefficient and wavelength, and a peak in the contribution of capillary waves to gas exchange at a wavelength around lambda = 3.6 mm. C1 USN, Res Lab, Washington, DC 20375 USA. RP Saylor, JR (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 40 TC 1 Z9 1 U1 1 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0280-6509 J9 TELLUS B JI Tellus Ser. B-Chem. Phys. Meteorol. PD JUL PY 1999 VL 51 IS 3 BP 616 EP 628 DI 10.1034/j.1600-0889.1999.t01-2-00004.x PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 220JK UT WOS:000081661700004 ER PT J AU Bitterwolf, TE Saygh, AA Bays, JT Weiss, CA Scallorn, WB Shade, JE Rheingold, AL Liable-Sands, L AF Bitterwolf, TE Saygh, AA Bays, JT Weiss, CA Scallorn, WB Shade, JE Rheingold, AL Liable-Sands, L TI Synthesis, Nujol matrix and solution photochemistry of M(CO)(2)[eta(5),eta(3)-C5H4-C(CH3)(2)-C5H6] (where M = Cr or Mo): molecular structures of Cr(CO)(2)[eta(5),eta(3)-C5H4-C(CH3)(2)-C5H6], Mo(CO)(2)[eta(5),eta(3)-C5H4-C(CH3)(2)-C5H6], and Mo(CO)[P(C6H5)(3)][eta(5),eta(3)-C5H4-C(CH3)(2)-C5H6] SO JOURNAL OF ORGANOMETALLIC CHEMISTRY LA English DT Article DE organometallic photochemistry; matrix photochemistry; chromium allyl; molybdenum allyl; haptotropic rearrangement ID COMPLEXES; LIGAND AB Reaction of chromium or molybdenum carbonyl with 2,2-bis(cyclopentadienyl)propane yields mixtures of products including M-2(CO)(6)[eta(5),eta(5)-C5H4-C(CH3)(2)-C5H4]. M-2(CO)(6)[eta(5)-C5H4-C(CH3)(2)-C5H4](2), and the title compounds, M(CO)(2)[eta(5),eta(3)-C5H4C-(CH3)(2)-C5H6], in which an eta(3)-pentenyl group is tethered to the eta(5)-cyclopentadienyl (Cp) group by a 2,2-propyl linkage. Although several isomers are possible for the cyclopentenyl groups, chromium and molybdenum appear to form only single, but unique isomers. Photolysis of M(CO)(2)[eta(5),eta(3)-C5H4-C(CH3)(2)-C5H6], M = Cr or Mo, in Nujol glass at ca, 77 K has been found to be wavelength-dependent with low energy photolyses resulting in eta(3)-->eta(1) transformations while higher energy photolyses result in loss of carbon monoxide. Solution photolysis of the molybdenum derivative with triphenylphosphine yields as a first product Mo(CO)(2)[P(C6H5)(3)][eta(5),eta(1)-C5H4-C(CH3)(2)- which undergoes decomposition upon work-up to yield both starting material, and Mo(CO)[P(C6H5)(3)][eta(5).eta(3)-C5H4-C(CH3)(2) -C5H6]. The molecular structures of three compounds have been determined: Mo(CO)(2)[eta(5), eta(3)-C5H4-C(CH3)(2)-C5H6]: monoclinic, P2(t)/c a = 8.2767(4), b = 19.875(1) c = 7.960(1) Angstrom, beta = 96,720(6)degrees V = 1300.4(1) Angstrom(3), Z = 4, R(F)= 2.82; Cr(CO)(2)[eta(5),eta(3)-C5H4-C(CH3)(2)-C5H6]: monoclinic. p2(1)/c. a = 9.960(1) b = 9.1015(6), c = 13.997(1) Angstrom, beta = 92.460(9)degrees, V= 1267.7(2) Angstrom(3), Z = 4, R(F)= 4.67; Mo(CO)[P(C6H5)(3)][eta(5), eta(3)-C5H4-C(CH3)(2)-C5H6]: monoclinic, P2(1)/c, a = 7.939(1), b = 22.381(3), c = 15.050(2) Angstrom, beta = 103.55(1)degrees, V = 2599.8(5) Angstrom(3), Z = 4, R(F) = 4.01. (C) 1999 Published by Elsevier Science S.A. All rights reserved. C1 Univ Idaho, Dept Chem, Moscow, ID 83844 USA. USN Acad, Dept Chem, Annapolis, MD 21404 USA. Univ Delaware, Dept Chem, Newark, DE 19716 USA. RP Bitterwolf, TE (reprint author), Univ Idaho, Dept Chem, Moscow, ID 83844 USA. NR 7 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0022-328X J9 J ORGANOMET CHEM JI J. Organomet. Chem. PD JUN 30 PY 1999 VL 583 IS 1-2 BP 152 EP 161 DI 10.1016/S0022-328X(99)00118-7 PG 10 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 210HV UT WOS:000081099800021 ER PT J AU Claassen, JH Booth, JC Beall, JA Rudman, DA Vale, LR Ono, RH AF Claassen, JH Booth, JC Beall, JA Rudman, DA Vale, LR Ono, RH TI Nonlinear inductive response of high temperature superconducting films measured by the mutual inductance technique SO APPLIED PHYSICS LETTERS LA English DT Article ID MICROSTRIP RESONATOR; THIN-FILMS; INTERMODULATION AB The dependence of the penetration depth lambda on current density J in an unpatterned superconducting film can be measured with a pair of small coaxial coils positioned on opposite sides of the film. Mutual inductance measurements in this configuration with a direct-current (dc) current component in one of the coils provide a means to determine lambda(J). It is possible to separate out the effects of heating by initially trapping a persistent current in the film. The nonlinear (current-dependent) coefficients of lambda(J) measured by this "dc" technique agree well with those measured by third harmonic generation in coplanar waveguide transmission lines at 5 GHz. This nondestructure technique could be used to screen films before incorporating them into circuits sensitive to nonlinear effects. [S0003-6951(99)03226-X]. C1 USN, Res Lab, Washington, DC 20375 USA. Natl Inst Stand & Technol, Boulder, CO 80303 USA. RP Claassen, JH (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 11 TC 16 Z9 16 U1 2 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JUN 28 PY 1999 VL 74 IS 26 BP 4023 EP 4025 DI 10.1063/1.123248 PG 3 WC Physics, Applied SC Physics GA 208MB UT WOS:000080994200035 ER PT J AU Cukauskas, EJ Kirchoefer, SW DeSisto, WJ Pond, JM AF Cukauskas, EJ Kirchoefer, SW DeSisto, WJ Pond, JM TI Ba(1-x)SrxTiO3 thin films by off-axis cosputtering BaTiO3 and SrTiO3 SO APPLIED PHYSICS LETTERS LA English DT Article ID DEPOSITION; YBA2CU3O7; (BA AB Thin films of Ba(1-x)SrxTiO3 (BST) have been deposited by off-axis cosputtering targets of SrTiO3 (STO) and BaTiO3 (BTO). The films were grown on (100) MgO and LaAlO3 substrates at 550 degrees C at an argon/oxygen gas pressure of 20 Pa. Reaction of the sputtered species in the plasma resulted in the growth of BST films. The film composition was set by the relative power levels of the STO and BTO targets. X-ray diffractometry indicated the as-deposited films were predominantly (h00) oriented. The calculated lattice parameter was 3.955+/-0.01 Angstrom, slightly larger than bulk Ba0.5Sr0.5TiO3. Postannealing the films in flowing O-2 at 780 degrees C resulted in greater peak heights and no change in orientation. Capacitance-voltage characteristics measured at 10 GHz yielded Q's of 65 with nearly 14% tuning for BST on LAO and Q > 1000 with a 2% tuning for films on MgO. [S0003-6951(99)02926-5]. C1 USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. RP Cukauskas, EJ (reprint author), USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. NR 12 TC 30 Z9 30 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JUN 28 PY 1999 VL 74 IS 26 BP 4034 EP 4036 DI 10.1063/1.123252 PG 3 WC Physics, Applied SC Physics GA 208MB UT WOS:000080994200039 ER PT J AU Dobisz, EA Brandow, SL Bass, R Shirey, LM AF Dobisz, EA Brandow, SL Bass, R Shirey, LM TI Resolution of polymethyl methacrylate: Molecular weights of 950 000 vs 50 000 SO APPLIED PHYSICS LETTERS LA English DT Article ID FABRICATION; EXPOSURE AB The work examines the resolution and line-to-line resolution of two molecular weights of polymethyl methacrylate (PMMA), developed in 25%-50% solutions of methylisobutyl ketone in isopropanol. Both PMMA's exhibited similar minimum linewidths of 15-18 nm. Measured linespread functions showed primary Gaussian standard deviations of 11.7 and 28 nm for the 950 and 50 K molecular weight PMMAs, respectively. Developer strength produced less than or equal to 1 nm difference in the width of the linespread function. Atomic force microscope images of latent grating patterns show the same line-to-line resolution for the two undeveloped resists. Developed gratings show the 950 K PMMA to have superior line-to-line resolution. The results are analyzed through integration of the measured linespread functions. (C) 1999 American Institute of Physics. [S0003-6951(99)02726-6]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Dobisz, EA (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Shirey, Loretta/B-3164-2013 OI Shirey, Loretta/0000-0003-2600-3405 NR 10 TC 8 Z9 8 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JUN 28 PY 1999 VL 74 IS 26 BP 4064 EP 4066 DI 10.1063/1.123262 PG 3 WC Physics, Applied SC Physics GA 208MB UT WOS:000080994200049 ER PT J AU Abdeen, HH Attallah, AFM Mansour, MM Harrison, RA AF Abdeen, HH Attallah, AFM Mansour, MM Harrison, RA TI Molecular cloning and characterization of the polypeptide backbone of Schistosoma mansoni circulating cathodic antigen SO MOLECULAR AND BIOCHEMICAL PARASITOLOGY LA English DT Article DE Schistosoma mansoni; Schistosoma haematobium; circulating cathodic antigen; diagnosis; cloning and expression ID LINKED POLYSACCHARIDE; LEWIS-X; URINE; ADHESION; SERUM; GLYCOPROTEINS; INFECTIONS; INTEGRINS; CAA; CCA AB One of the candidate schistosome antigens for the development of a circulating antigen detection diagnostic assay is the circulating cathodic antigen (CCA). Detection of CCA in urine provides a non-invasive assay with high sensitivity. Previously we reported that CCA is secreted in patients' urine as a small molecular weight material which is probably of a proteinaceous nature. In an attempt to further characterize the secreted component of CCA, we used a monoclonal antibody (MAb) reactive with urine-CCA to isolate an adult worm cDNA clone (SmN3-1) that encodes the polypeptide backbone of CCA. The sequence, gene organization and expression of SmN3-1 were analyzed. The 1.6 kb nucleotide and 347 amino acid sequences of SmN3-1 showed no significant homology to any published sequence. The size and antigenic properties of the expression product of SmN3-1 in Escherichia coli greatly resembled the CCA molecule excreted in urine, suggesting that the latter is primarily composed of the protein element of CCA. (C) 1999 Published by Elsevier Science B.V. C1 USN, Med Res Unit 3, Cairo, Egypt. RP Abdeen, HH (reprint author), USN, Med Res Unit 3, Cairo, Egypt. NR 33 TC 2 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-6851 J9 MOL BIOCHEM PARASIT JI Mol. Biochem. Parasitol. PD JUN 25 PY 1999 VL 101 IS 1-2 BP 149 EP 159 DI 10.1016/S0166-6851(99)00068-7 PG 11 WC Biochemistry & Molecular Biology; Parasitology SC Biochemistry & Molecular Biology; Parasitology GA 210TB UT WOS:000081119800013 PM 10413050 ER PT J AU Balasubramanian, M Melendres, CA Mansour, AN AF Balasubramanian, M Melendres, CA Mansour, AN TI An X-ray absorption study of the local structure of cerium in electrochemically deposited thin films SO THIN SOLID FILMS LA English DT Article DE cerium; corrosion; electrochemistry; X-ray absorption ID FINE-STRUCTURE; EDGE; INHIBITORS; CORROSION; ALUMINUM; ALLOYS; EXAFS AB We have utilized the technique of X-ray absorption fine structure (XAFS) to study the oxidation state and structure of cerium in electrochemically deposited thin films of cerium oxide (hydroxide). We find that anodic deposition results in a hydrous cerium oxide phase in which the oxidation state of cerium is 4+. This material is highly structurally disordered but still has a medium range local structure (similar to 4 Angstrom) similar to CeO2. On the other hand, cathodic deposition leads to a Ce3+ phase, which is susceptible to oxidation on exposure to air or by dissolved oxygen in solution. Our results may be relevant to understanding the structure of cerium inhibitors incorporated in corrosion films on aluminium and its alloys. (C) 1999 Elsevier Science S.A. All rights reserved. C1 Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. RP Balasubramanian, M (reprint author), Argonne Natl Lab, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 24 TC 41 Z9 44 U1 1 U2 7 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD JUN 22 PY 1999 VL 347 IS 1-2 BP 178 EP 183 DI 10.1016/S0040-6090(98)01754-4 PG 6 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 207RP UT WOS:000080949800025 ER PT J AU Bermudez, VM AF Bermudez, VM TI Study of the chemistry of NH3 on aluminum nitride and oxynitride under steady-state conditions using external-reflection infrared spectroscopy SO THIN SOLID FILMS LA English DT Article DE aluminum oxide; aluminum nitride; ammonia; infrared spectroscopy ID GROUP-III NITRIDES; THIN-FILM GROWTH; RAMAN-SPECTROSCOPY; ALN; GAN; SURFACE; AMMONIA; TRIMETHYLALUMINUM; ADSORPTION; PRECURSORS AB Polarization-modulated Fourier-transform infrared reflection absorption spectroscopy has been applied to the characterization of thin films of AlN and Al oxynitride ('AION') on NiAL(111) and to the observation of surface chemical processes under steady-state conditions in a static NH3 ambient of up to 200 Torr. AN films, grown by dosing NiAl(111) with NH3 at similar to 1230 K, are found to be structurally inhomogeneous and largely disordered, with no evidence of chemisorption at 300 K in a background of 200 Torr of NH3. AlON films, grown by dosing NiAl(111) with NO near 300 K and annealing to 1000 K, appear more homogeneous and show distinct surface and bulk vibrational modes. The former responds reversibly to chemisorbed NH3 which can be detected under steady-state conditions by the appearance of the delta(s) symmetric deformation mode. In comparison to similar results for Al2O3, the delta(s) frequency indicates a lesser degree of Lewis acidity for the AlON surface. (C) 1999 Elsevier Science S.A. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. RP Bermudez, VM (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 30 TC 11 Z9 11 U1 2 U2 12 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD JUN 22 PY 1999 VL 347 IS 1-2 BP 195 EP 200 DI 10.1016/S0040-6090(99)00003-6 PG 6 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 207RP UT WOS:000080949800027 ER PT J AU Romero, MJ Araujo, D Garcia, R Walters, RJ Summers, GP Messenger, SR AF Romero, MJ Araujo, D Garcia, R Walters, RJ Summers, GP Messenger, SR TI Spatial distribution of radiation-induced defects in p(+)-n InGaP solar cells SO APPLIED PHYSICS LETTERS LA English DT Article ID ELECTRON-IRRADIATION; GAAS AB The spatial distribution of radiation-induced, radiative recombination centers in single-junction p(+)-n InGaP solar cells irradiated by 1 MeV electrons or 3 MeV protons has been determined from cathodoluminescence (CL) spectra. The energy levels of the radiation-induced, nonradiative recombination centers were determined from the temperature dependence of the CL intensity. (C) 1999 American Institute of Physics. [S0003-6951(99)05025-1]. C1 Univ Cadiz, Fac Ciencias, Dept Ciencia Mat & IM & QI, E-11510 Puerto Real, Cadiz, Spain. USN, Res Lab, Washington, DC 20375 USA. SFA Inc, Largo, MD 20744 USA. RP Romero, MJ (reprint author), Univ Cadiz, Fac Ciencias, Dept Ciencia Mat & IM & QI, Aptdo 40, E-11510 Puerto Real, Cadiz, Spain. OI Garcia Roja, Rafael/0000-0003-2867-7016 NR 11 TC 4 Z9 5 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JUN 21 PY 1999 VL 74 IS 25 BP 3812 EP 3814 DI 10.1063/1.124188 PG 3 WC Physics, Applied SC Physics GA 206CB UT WOS:000080857600020 ER PT J AU Edelstein, AS Kodama, RH Miller, M Browning, V Lubitz, P Cheng, SF Sieber, H AF Edelstein, AS Kodama, RH Miller, M Browning, V Lubitz, P Cheng, SF Sieber, H TI Interlayer coupling and enhanced coercivity in ferromagnetic antiferromagnetic structures SO APPLIED PHYSICS LETTERS LA English DT Article ID THIN-FILMS; SUPERLATTICES; MULTILAYERS; RESONANCE; ANISOTROPY; TRILAYERS AB Magnetization and ferromagnetic resonance measurements provide evidence of ferromagnetic coupling between ferromagnetic (F) layers separated by an intervening layer of antiferromagnetic (AF) NiO of thickness, t(AF), where 7 nm < t(AF)< 13 nm. Near 300 K, due to this coupling, the coercivity H-c and M-H loop squareness in F/AF multilayers increases as one increases the number of layers. The increased H-c and squareness have potential application in thin film magnets. (C) 1999 American Institute of Physics. [S0003-6951(99)03225-8]. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Wisconsin, Dept Mat Sci & Engn, Madison, WI 53706 USA. RP Edelstein, AS (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 15 TC 16 Z9 18 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JUN 21 PY 1999 VL 74 IS 25 BP 3872 EP 3874 DI 10.1063/1.124208 PG 3 WC Physics, Applied SC Physics GA 206CB UT WOS:000080857600040 ER PT J AU Chen, LG Bi, YH Wu, C AF Chen, LG Bi, YH Wu, C TI The influence of nonlinear flow resistance relations on the power and efficiency from fluid flow SO JOURNAL OF PHYSICS D-APPLIED PHYSICS LA English DT Article ID HEAT-TRANSFER LAW; FINITE-TIME; CHEMICAL ENGINES; MAXIMUM POWER; CARNOT ENGINE; PERFORMANCE; THERMODYNAMICS AB The endoreversible thermodynamic theory of heat engines is extended to fluid flow power converters. The relation between power output and efficiency, which involves the maximum (reversible) efficiency (with zero power output) as well as the maximum power and the corresponding efficiency bound, is derived based on the nonlinear flow resistance relations. Some modification to the results from recent literature is performed, and a theory of generalized thermodynamic optimization is provided. C1 Naval Acad Engn, Fac 306, Wuhan 430033, Peoples R China. Beijing Polytech Univ, Fac Air Conditioning, Beijing 100022, Peoples R China. USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. RP Chen, LG (reprint author), Naval Acad Engn, Fac 306, Wuhan 430033, Peoples R China. NR 25 TC 23 Z9 29 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0022-3727 J9 J PHYS D APPL PHYS JI J. Phys. D-Appl. Phys. PD JUN 21 PY 1999 VL 32 IS 12 BP 1346 EP 1349 DI 10.1088/0022-3727/32/12/310 PG 4 WC Physics, Applied SC Physics GA 211GV UT WOS:000081153300011 ER PT J AU Bandyopadhyay, RM Shahbaz, T Charles, PA Naylor, T AF Bandyopadhyay, RM Shahbaz, T Charles, PA Naylor, T TI Infrared spectroscopy of low-mass X-ray binaries - II SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE accretion, accretion discs; binaries : close; binaries : spectroscopic; infrared : stars; X-rays : stars ID OPTICAL-IDENTIFICATION; ACCRETION DISKS; SCO X-2; PHOTOMETRY; COUNTERPARTS; BEHAVIOR; GX-349+2; GX-13+1; SEARCH; PERIOD AB Using CGS4 on UKIRT, we have obtained 2.00-2.45 mu m infrared spectra of a number of low mace X-ray binaries including Sco X-l,Sco X-2 and GX13+1. Sco X-1 shows emission lines only, supporting our previous conclusion that the spectral type of the evolved secondary must be earlier than G5, Emission lines are also seen in the spectrum of Sco X-2, confirming the identity of the IR counterpart. We report the detection of CO bands in GX13+1, and estimate the most likely spectral type of the secondary to be K5III. We also find P Cygni-type profiles in the Brackett gamma lines of Sco X-l and GX13+1, indicating the presence of high-velocity outflows in these systems, We present spectra of candidate IR counterparts to several other elusive X-ray binaries. Finally, implications for the nature and classification of these systems are discussed. C1 Univ Oxford, Dept Astrophys, Oxford OX1 3RH, England. Univ Keele, Dept Phys, Keele ST5 5BG, Staffs, England. RP Bandyopadhyay, RM (reprint author), USN, Res Lab, Code 7621,4555 Overlook Ave SW, Washington, DC 20375 USA. RI Naylor, Tim /A-9465-2015 NR 58 TC 61 Z9 62 U1 0 U2 0 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD JUN 21 PY 1999 VL 306 IS 2 BP 417 EP 426 DI 10.1046/j.1365-8711.1999.02547.x PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 212FL UT WOS:000081206600015 ER PT J AU Bellitto, VJ Thoms, BD Koleske, DD Wickenden, AE Henry, RL AF Bellitto, VJ Thoms, BD Koleske, DD Wickenden, AE Henry, RL TI HREELS of H/GaN(0001): evidence for Ga termination SO SURFACE SCIENCE LA English DT Article DE gallium nitride; GaN; HREELS; hydrogen; termination ID CHEMICAL-VAPOR-DEPOSITION; MOLECULAR-BEAM EPITAXY; WURTZITE GAN; GAN(0001)-(1X1) SURFACE; ELECTRONIC-PROPERTIES; GAAS(110) SURFACES; GALLIUM NITRIDE; HYDROGEN; AMMONIA; GROWTH AB Two issues relevant to the growth and processing of GaN are the termination of the GaN(0001) surface and its reaction with hydrogen. We have used high-resolution electron energy loss spectroscopy (HREELS), low-energy electron diffraction (LEED), and Auger electron spectroscopy (AES) to study the adsorption of hydrogen on MOCVD-grown GaN(0001). LEED of the sputtered and annealed surface shows evidence of facetting. No adsorbate vibrations are observed on the clean surface by HREELS, only Fuchs-Kliewer phonons at intervals of 700 cm(-1) Following exposure of the clean GaN surface to hydrogen atoms, HREEL spectra show adsorbate loss peaks at 2580, 3280, and 3980 cm(-1). The Ga-H stretching vibration at 1880 cm(-1) becomes evident when the HREEL spectrum is deconvoluted to remove the phonon multiple-loss peaks. We assign the 2580, 3280, and 3980 cm(-1) peaks to combination modes of the Ga-H stretch and phonon(s). Upon dosing with deuterium, the Ga-D bending mode is observed at 400 cm(-1). No vibrational peaks due to N-H (N-D) species are observed after H (D) exposure. We conclude that sputtered and annealed GaN(0001) is Ga-terminated. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Georgia State Univ, Dept Phys & Astron, Atlanta, GA 30303 USA. USN, Res Lab, Div Elect Sci & Technol, Lab Adv Mat Synth, Washington, DC 20375 USA. RP Thoms, BD (reprint author), Georgia State Univ, Dept Phys & Astron, Atlanta, GA 30303 USA. RI Schaff, William/B-5839-2009 NR 42 TC 35 Z9 35 U1 1 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD JUN 21 PY 1999 VL 430 IS 1-3 BP 80 EP 88 DI 10.1016/S0039-6028(99)00403-3 PG 9 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 217GQ UT WOS:000081492000016 ER PT J AU Doschek, EE Laming, JM Doschek, GA Feldman, U Wilhelm, K AF Doschek, EE Laming, JM Doschek, GA Feldman, U Wilhelm, K TI A comparison of measurements of solar extreme-ultraviolet spectral line intensities emitted by C, N, O, and S ions with theoretical calculations SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : abundances; Sun : UV radiation ID ELECTRON-IMPACT EXCITATION; EFFECTIVE COLLISION STRENGTHS; RATE COEFFICIENTS; ATOMIC DATA; TRANSITION REGION; SUMER TELESCOPE; IRON PROJECT; IV; SUN; SPECTROMETER AB Atomic data for ionized atoms are important for many astrophysical applications. The launch of the Solar Ultraviolet Measurements of Emitted Radiation (SUMER) extreme-ultraviolet (EUV) spectrometer aboard the Solar and Heliospheric Observatory (SOHO) allows us to test the accuracy of certain computed relative excitation rate coefficients and transition probabilities for a number of important astrophysical ions. We use spectral line intensity ratios derived from SUMER spectra to compare these quantities with the best available theoretical calculations for transitions within the ions C II, N III, N IV, O III, O IV, O V, S III, S IV, and S V. The results of this work are important for many current and upcoming NASA astrophysics missions. In addition to the published atomic data, we calculate some new atomic data using the Hebrew University Lawrence Livermore Atomic Code (HULLAC). Our comparison of measured intensity ratios with theoretical predictions reveals significant discrepancies between the predicted and measured intensity ratios for several ions, particularly for S III, S IV, and S V. S III and S IV produce strong line emission in the Io torus. We discuss the methods we used to ensure that our ratios are accurate, the possible effects of Lyman continuum absorption on our data, and the ramifications of ignoring dielectronic capture resonances in certain transitions as a possible explanation for some of the discrepancies. C1 Yale Univ, New Haven, CT 06520 USA. Sachs Freeman Associates Inc, Largo, MD 20774 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Max Planck Inst Aeron, D-37191 Katlenburg Lindau, Germany. RP Doschek, EE (reprint author), Yale Univ, POb 200358, New Haven, CT 06520 USA. NR 28 TC 10 Z9 10 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUN 20 PY 1999 VL 518 IS 2 BP 909 EP 917 DI 10.1086/307313 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 211KA UT WOS:000081158700034 ER PT J AU Laming, JM Feldman, U Drake, JJ Lemaire, P AF Laming, JM Feldman, U Drake, JJ Lemaire, P TI The off-limb behavior of the first ionization potential effect in T > 5 x 10(5) K solar plasmas SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : abundances; Sun : corona; Sun : transition region; Sun : UV radiation ID STELLAR CORONAL ABUNDANCES; UNRESOLVED FINE-STRUCTURES; ELEMENTAL ABUNDANCES; TEMPERATURE REGION; TRANSITION REGION; SUMER TELESCOPE; ATMOSPHERE; SPECTRA; SOHO; SPECTROMETER AB We investigate the behavior of the solar first ionization potential (FIP) effect (the abundance enhancement of elements with first ionization potential of less than 10 eV in the corona with respect to photospheric values) with height above the limb in a region of diffuse quiet corona observed by the SUMER instrument on SOHO, with emphasis on so-called upper transition region lines. Previous disk observations have shown different abundance patterns in emission from lines at temperatures above and below similar to 8 x 10(5) K, with an FIP effect clearly visible at the higher temperatures and less so at the lower temperatures. Our initial aim is to determine whether such a difference is also visible in off-limb observations. We find a low-FIP element enhancement of a factor of 3-4 indicated in all line ratios. The Mg vn 868.11/Ne VII 895.17 ratio is also seen to decrease toward a photospheric value when tracked down from the corona to the limb. This is markedly different from the behavior of higher temperature line ratios and may be related to the differing heating and mass supply mechanisms for plasmas at temperatures above and below similar to 8 x 10(5) K. An additional unexpected feature of our observations is that in low-FIP/high-FIP line ratios formed at temperatures close to the freeze-in temperature of the fast solar wind (similar to 10(6) K), there is also a small diminution of the FIP enhancement at the highest altitudes observed in this study. We discuss the possible relevance of this to the origin of the fast solar wind. C1 SFA Inc, Largo, MD 20774 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Smithsonian Astrophys Lab, Cambridge, MA 02138 USA. Univ Paris 11, Inst Astrophys Spatiale, CNRS, F-91405 Orsay, France. RP Laming, JM (reprint author), SFA Inc, Largo, MD 20774 USA. NR 34 TC 13 Z9 13 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUN 20 PY 1999 VL 518 IS 2 BP 926 EP 936 DI 10.1086/307294 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 211KA UT WOS:000081158700036 ER PT J AU Huang, L Massa, L Karle, J AF Huang, L Massa, L Karle, J TI Quantum crystallography applied to crystalline maleic anhydride SO INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY LA English DT Article DE crystalline state; structure factor magnitudes; atomic coordinates; theoretical chemistry AB Quantum crystallography (QCr) is a term that concerns techniques for using crystallographic information to enhance quantum mechanical calculations and the information derived from them. In our approach to QCr, we use molecular orbitals and a single-determinant density matrix formalism to develop a quantum mechanical model. Our initial application to a test material, crystalline maleic anhydride, involved the adjustment of the elements in the density (projector) matrix and some others in the quantum mechanical model. The purpose was to optimize the fit between the experimental structure factor magnitudes and the values of those magnitudes obtained from the quantum mechanical model. The adjustment of the projector matrix preserved the idempotency and normalization properties of the matrix. In this application, it was also found that it was necessary to correct the X-ray diffraction data for systematic errors. An effective statistical method for doing this was developed from quantum mechanical theory. There were a number of special features of this investigation that emerged as it progressed. The mirror plane in maleic anhydride, for example, was quite useful because, in the absence of significant interactions between the molecules in the crystal, charge distributions on both sides of the mirror plane should be essentially the same. Deviations raised questions that resulted in improved procedures. The quality of theoretical results as a function of basis set and mode of calculation is also part of this investigation. One result of the information obtained from various aspects of this study is the potential for greater efficiency in the procedures and calculations. The calculations for maleic anhydride based on its structure concern the number of electrons per atom, various energies, and electron density contours. Related theoretical calculations based on geometry optimization were also made. (C) 1999 John Wiley & Sons, Inc. C1 USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. CUNY Hunter Coll, New York, NY 10021 USA. CUNY, Grad Ctr, New York, NY 10021 USA. Geocenters Inc, Ft Washington, MD 20744 USA. RP Karle, J (reprint author), USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. NR 9 TC 12 Z9 12 U1 1 U2 4 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0020-7608 J9 INT J QUANTUM CHEM JI Int. J. Quantum Chem. PD JUN 20 PY 1999 VL 73 IS 5 BP 439 EP 450 DI 10.1002/(SICI)1097-461X(1999)73:5<439::AID-QUA7>3.3.CO;2-X PG 12 WC Chemistry, Physical; Mathematics, Interdisciplinary Applications; Physics, Atomic, Molecular & Chemical SC Chemistry; Mathematics; Physics GA 199CE UT WOS:000080461100007 ER PT J AU Dvorkin, J Prasad, M Sakai, A Lavoie, D AF Dvorkin, J Prasad, M Sakai, A Lavoie, D TI Elasticity of marine sediments: Rock physics modeling SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID EQUATION; DEPTH AB We offer an effective medium model for the elastic moduli of high-porosity ocean-bottom sediments. The elastic constants of the dry-sediment frame depend on porosity, elastic moduli of the solid phase, and effective pressure. The model connects two end points in the elastic-modulus-porosity plane: the Hertz-Mindlin modulus of a dense elastic sphere pack at critical porosity; and zero at 100% porosity. The elastic moduli of saturated sediment are calculated from those of the dry frame using Gassmann's equation. Unlike the suspension model, our model assigns non-zero elastic constants to the dry-sediment frame and can predict the shear-wave velocity. Unlike various modifications of the traveltime-average equation, it is first-principle-based and contains only physical parameters. We justify this model by matching sonic data in shallow marine sediments and in an ODP well. C1 Stanford Univ, Dept Geophys, Stanford, CA 94305 USA. Japan Petr Explorat Co Ltd Japex, Tokyo, Japan. USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Dvorkin, J (reprint author), Stanford Univ, Dept Geophys, Stanford, CA 94305 USA. RI Prasad, Manika/B-2569-2014 OI Prasad, Manika/0000-0002-8009-0768 NR 19 TC 101 Z9 110 U1 3 U2 25 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JUN 15 PY 1999 VL 26 IS 12 BP 1781 EP 1784 DI 10.1029/1999GL900332 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 207DT UT WOS:000080920700036 ER PT J AU Owrutsky, JC Baronavski, AP AF Owrutsky, JC Baronavski, AP TI Ultrafast photodissociation dynamics of the S-1 and S-2 states of acetone SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID LASER-INDUCED FLUORESCENCE; 3S RYDBERG STATE; 193 NM; MULTIPHOTON IONIZATION; UNIMOLECULAR DISSOCIATION; STEPWISE DISSOCIATION; EMISSION-SPECTROSCOPY; TRANSLATIONAL ENERGY; INFRARED-EMISSION; ROTATIONAL-STATE AB The photodissociation dynamics for the two lowest excited electronic states (S-1 valence state and the S-2, 3s Rydberg state) of acetone (h(6) and d(6)) have been studied using femtosecond mass-resolved photoionization spectroscopy. The S-1 state dynamics was investigated by near ultraviolet (UV) pump (similar to 265 nm) and deep UV (205 nm) or visible (410 nm) probe. The primary dissociation time is instrument-limited, providing a 200 fs upper limit to the lifetime. The acetyl ion signal exhibits a subpicosecond decay and a persistent signal. The fast decay is consistent with results from Kim et al. [J. Chem. Phys. 103, 477 (1995)] for two-photon excitation to near the 4s state. The persistent signal is due to probe- induced ionization of acetyl radicals that are stable with respect to secondary dissociation. The S-2 excited state lifetime measured for acetone-d(6) using 194 pump and 259 nm probe is 13.5 +/- 1.0 ps. This is almost three times longer than we previously determined for this state in acetone-h(6), 4.7 +/- 0.2 ps. The secondary dissociation time for acetyl-d(3) measured with two-photon ionization probe at 388 nm is 3.0 +/- 1.0 ps. This is the same (within the experimental uncertainty) as our result for acetyl-h(3) (3.1 +/- 0.5 ps), so that there is no apparent isotope effect. The calculated RRKM (Rice-Ramsperger-Kassel-Marcus) rate, however, is significantly faster for acetyl-h(3) at the same internal energy, so that the isotopic dependence of the rate deviates from the RRKM predictions. Consequently, there is either an isotope dependence in the energy partitioning for primary dissociation or a reverse isotope effect in the secondary dissociation, or both. In the latter, more likely case, this indicates that the secondary dissociation does not conform to a statistical, RRKM-type unimolecular dissociation. [S0021-9606(99)00223-8]. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Owrutsky, JC (reprint author), USN, Res Lab, Div Chem, Code 6111, Washington, DC 20375 USA. EM jeff.owrutsky@nrl.navy.mil RI Owrutsky, Jeffrey/K-7649-2012 NR 49 TC 65 Z9 65 U1 4 U2 19 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD JUN 15 PY 1999 VL 110 IS 23 BP 11206 EP 11213 DI 10.1063/1.478003 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 200CH UT WOS:000080521200014 ER PT J AU Leon, C Ngai, KL Roland, CM AF Leon, C Ngai, KL Roland, CM TI Relationship between the primary and secondary dielectric relaxation processes in propylene glycol and its oligomers SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID GLASS-FORMING MATERIALS; ALPHA-RELAXATION; POLY(PROPYLENE OXIDE); SEGMENTAL RELAXATION; MOLECULAR GLASSES; BETA-RELAXATION; COUPLING MODEL; FAST DYNAMICS; LIQUIDS; TRANSITION AB Dielectric relaxation measurements were performed on propylene glycol (PG) and oligomers having different number of repeat units (N=2, 3, and 69). The primary alpha-relaxation had the Kohlrausch-Williams-Watts (KWW) form, with a stretch exponent (1-n) which decreased with increasing N. The temperature dependence of the alpha-relaxation time, as reflected in the fragility index, increased with N. A broad, rather symmetric secondary beta-relaxation was observed at higher frequencies in the dielectric loss spectrum for all samples with N>1. This is the first observation of the beta-relaxation peak in dipropylene glycol (N=2) and tripropylene glycol (N=3). The separation between the a-and beta-relaxations increased with increasing N. This trend indicates that the separation is minimal in PG, which makes it difficult to resolve the beta-relaxation from the more intense alpha-relaxation. This, together with the fact that the strength of the beta-relaxation decreases with the molecular weight of PPG, as found by Johari and coworkers, explains the absence of an observable beta-peak or shoulder in isothermal or isochronal dielectric measurement on PG. It is proposed that the deviation of the dielectric loss peak for PG from either the KWW or the Cole-Davidson functions at higher frequencies is due to a beta-relaxation masked by the alpha-process. The same conclusion was reached by Johari and co-workers, based on evidence from their "difference isochrone method.'' Finally, we show that the data from oligomers of propylene glycol support the recently proposed correlation of tau(beta)(T-g) with (1-n) and the rough agreement between tau(beta)(T-g) and the primitive relaxation time of the coupling model at temperatures above T-g. [S0021-9606(99)51423-2]. C1 USN, Res Lab, Washington, DC 20375 USA. F CC Fis, Madrid 28040, Spain. RP Leon, C (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Leon, Carlos/A-5587-2008 OI Leon, Carlos/0000-0002-3262-1843 NR 45 TC 165 Z9 166 U1 3 U2 20 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUN 15 PY 1999 VL 110 IS 23 BP 11585 EP 11591 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 200CH UT WOS:000080521200053 ER PT J AU Holland, KT Holman, RA AF Holland, KT Holman, RA TI Wavenumber-frequency structure of infragravity swash motions SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID MEAN LONGSHORE-CURRENT; EDGE WAVES; NATURAL BEACH; SHEAR INSTABILITIES; FIELD OBSERVATIONS; SURF BEAT; RUN-UP; GENERATION; SPECTRA; BARS AB Alongshore-separated time series of natural swash motions were obtained over a range of environmental conditions using a video technique. Although the frequency spectra and normalized wavenumber spectra for these motions were particularly bland, wavenumber-frequency spectra of these data showed clear partitions of infragravity band energy levels associated with various wave types. For the frequencies 0.025 < f less than or equal to 0.05 Hz, 45 +/- 13% of the shoreline variance was, on average, associated with high-mode (n greater than or equal to 2) edge waves and/or leaky waves, while approximately half that amount was associated with low-mode edge waves. Gravity wave motions (comprising both edge and leaky modes) were typically dominant in a lower-frequency band (0.001 < f less than or equal to 0.025 Hz). A substantial portion of the variance in this band (21 +/- 10%, with a maximum of 38%), however, was identified as a nondispersive waveform with wavenumbers well outside of the wavenumber-frequency bounds for gravity waves. Surprisingly: this nongravity swash variance showed no significant dependence on mean alongshore current strength or mean alongshore current sheer as measured in the surf zone trough separating the shoreline from an offshore bar. In addition, the celerities of these swash zone nondispersive waves were found to differ in magnitude, and in one instance, sign, from celerities of similarly structured waves measured farther offshore in the surf zone. These unexpected observations with respect to low-frequency, nongravity swash energy imply a strong decorrelation between trough and shoreline fluid motions. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. Oregon State Univ, Coll Ocean & Atmospher Sci, Corvallis, OR 97331 USA. RP Holland, KT (reprint author), USN, Res Lab, Code 7442,Bldg 2438, Stennis Space Ctr, MS 39529 USA. RI Holland, K. Todd/A-7673-2011 OI Holland, K. Todd/0000-0002-4601-6097 NR 40 TC 28 Z9 29 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD JUN 15 PY 1999 VL 104 IS C6 BP 13479 EP 13488 DI 10.1029/1999JC900075 PG 10 WC Oceanography SC Oceanography GA 207BF UT WOS:000080914900016 ER PT J AU Bacmeister, JT Eckermann, SD Tsias, A Carslaw, KS Peter, T AF Bacmeister, JT Eckermann, SD Tsias, A Carslaw, KS Peter, T TI Mesoscale temperature fluctuations induced by a spectrum of gravity waves: A comparison of parameterizations and their impact on stratospheric microphysics SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID SULFURIC-ACID DROPLETS; INDUCED ICE PARTICLES; CLOUD FORMATION; ARCTIC STRATOSPHERE; NOCTILUCENT CLOUDS; UPPER TROPOSPHERE; OZONE DEPLETION; MOUNTAIN WAVES; NUMBER SPECTRA; MOTIONS AB Power spectral densities (PSDs) of mesoscale fluctuations of temperature and rate of change of temperature (heating-cooling rate) due to a spectrum of stratospheric gravity waves are derived using canonical spectral forms based on observations and linear gravity wave theory. The parameterization developed hers assumes a continuous distribution of horizontal wave phase speeds, as opposed to a previous spectral parameterization in which all waves were assigned stationary ground-based phase speeds. Significantly different heating-cooling rate PSDs result in each case. The differences are largest at small horizontal scales, where the continuous phase-speed parameterization yields heating-cooling rare PSDs that are several orders of magnitude smaller than in the stationary phase-speed parameterization. A simple Monte Carlo method is used to synthesize randomly phased temperature perturbation time series within tagged air parcels using either spectral parameterization. These time series are incorporated into a nonequilibrium, microphysical trajectory-box model to assess the microphysical consequences of each parameterization. Collated results yield a "natural" geophysical scatter of instantaneous aerosol volumes within air parcels away from equilibrium conditions. The amount of scatter was much smaller when the continuous phase-speed parameterization was used. C1 Univ Space Res Assoc, Columbia, MD USA. Computat Phys Inc, Fairfax, VA USA. Max Planck Inst Chem, D-55128 Mainz, Germany. RP USN, Res Lab, EO Hulburt Ctr Space Res, Code 7641, Washington, DC 20375 USA. EM eckerman@uap.nrl.navy.mil RI Carslaw, Ken/C-8514-2009 OI Carslaw, Ken/0000-0002-6800-154X NR 52 TC 25 Z9 25 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 EI 1520-0469 J9 J ATMOS SCI JI J. Atmos. Sci. PD JUN 15 PY 1999 VL 56 IS 12 BP 1913 EP 1924 DI 10.1175/1520-0469(1999)056<1913:MTFIBA>2.0.CO;2 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 210ZR UT WOS:000081135900009 ER PT J AU Price, GL Truitt, GH AF Price, GL Truitt, GH TI On the ranks of Toeplitz matrices over finite fields SO LINEAR ALGEBRA AND ITS APPLICATIONS LA English DT Article ID SHIFTS AB Let T be a skew-symmetric Toeplitz matrix with entries in a finite field. For all positive integers n let T-n be the upper n x n corner of T, with nullity upsilon(n) = upsilon(T-n). The sequence {v(n): n is an element of N} satisfies a unimodality property and is eventually periodic if the entries of T satisfy a periodicity condition. We compute the maximum value and the period of the nullity sequence for Toeplitz matrices of finite bandwidth. This sequence satisfies a certain symmetry condition about its maximal values. These results apply to give some information about the ranks of general skew-symmetric Toeplitz matrices with eventually periodic entries. (C) 1999 Elsevier Science Inc. All rights reserved. C1 USN Acad, Dept Math, Annapolis, MD 21402 USA. RP Price, GL (reprint author), USN Acad, Dept Math, Annapolis, MD 21402 USA. NR 11 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 USA SN 0024-3795 J9 LINEAR ALGEBRA APPL JI Linear Alg. Appl. PD JUN 15 PY 1999 VL 294 IS 1-3 BP 49 EP 66 DI 10.1016/S0024-3795(99)00052-X PG 18 WC Mathematics, Applied; Mathematics SC Mathematics GA 221UB UT WOS:000081744100004 ER PT J AU Lee, EW Kalu, PN Brandao, L Es-Said, OS Foyos, J Garmestani, H AF Lee, EW Kalu, PN Brandao, L Es-Said, OS Foyos, J Garmestani, H TI The effect of off-axis thermomechanical processing on the mechanical behavior of textured 2095 Al-Li alloy SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE off-axis thermomechanical processing; mechanical behavior; 2095 Al-Li alloy ID MG-ZR ALLOY; MICROSTRUCTURE; ANISOTROPY; EVOLUTION; STRETCH AB This investigation was conducted to study the influence of off-axis deformation in the thermomechanical processing on the properties of Al-Li 2095 HT72 alloy sheet. The thermomechanical processing involved several stages. First, the as-received hot rolled sheet was solution heat treated at 510 degrees C for 30 min. Samples were then cut from the sheet and stretched off-axis at 0, 30, 60 and 90 degrees angles (stretch axis) to the original rolling direction. All the specimens were then aged at 180 degrees C for 24 h. Tensile coupons were then machined from each of these aged samples at 0, 30, 45, 60 and 90 degrees (tensile axis) to the rolling direction, then tested to failure. The crystallographic texture and tensile properties of the processed samples were evaluated, and were compared to the solution heat-treated material. In the solution heat-treated condition, the material was highly textured with a very strong Brass component. Off-axis stretch followed by aging had little or no effect on the texture development of the solution heat-treated material. Upon testing, samples with stretch axis at 0 degrees showed pronounced mechanical anisotropy; specimens tested at 45 degrees showed about 40% drop in tensile and yield strength values when compared to those tested at 0 degrees. However, stretching along 60 degrees or 90 degrees directions minimized mechanical anisotropy. The texture characteristics of all tested samples were determined and related to the changes in the mechanical properties. An attempt was made to correlate the data with some texture theories. Analysis of the results and normalization based on the Taylor's factor showed that that crystallographic texture contributes only partly to the total mechanical anisotropy. (C) 1999 Elsevier Science S.A. All rights reserved. C1 FAMU FSU Coll Engn, Dept Engn Mech, Tallahassee, FL 32310 USA. FAMU FSU Coll Engn, Ctr Mat Res & Technol, MARTECH, Tallahassee, FL 32310 USA. USN, Air Warfare Ctr, A C Div, Warminster, PA 18974 USA. IME, Dept Engn Mecan & Mat, BR-22290270 Rio De Janeiro, Brazil. Loyola Marymount Univ, Dept Mech Engn, Los Angeles, CA 90045 USA. RP Garmestani, H (reprint author), FAMU FSU Coll Engn, Dept Engn Mech, Room 229,2525 Pottsdamer Rd, Tallahassee, FL 32310 USA. RI Brandao, Luiz Paulo/B-2714-2013 OI Brandao, Luiz Paulo/0000-0002-2623-648X NR 25 TC 8 Z9 12 U1 2 U2 10 PU ELSEVIER SCIENCE SA 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 JUN 15 PY 1999 VL 265 IS 1-2 BP 100 EP 109 DI 10.1016/S0921-5093(98)01150-2 PG 10 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 194TA UT WOS:000080208600013 ER PT J AU McNelley, TR McMahon, ME Perez-Prado, MT AF McNelley, TR McMahon, ME Perez-Prado, MT TI Grain boundary evolution and continuous recrystallization of a superplastic Al-Cu-Zr alloy SO PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES LA English DT Article DE deformation processing; superplasticity; Supral; grain boundaries; boundary misorientation; continuous polycrystallization ID ALUMINUM; MICROSTRUCTURES; DEFORMATION; MICROTEXTURE; REFINEMENT; TEXTURES AB Two distinct microstructural transformation processes have been observed to enable superplastic response in aluminium alloys, depending upon the composition and thermomechanical history. Continuous recrystallization has been used to describe the transformation leading to a superplastically enabled state in alloys that respond to processing, as does the commercial alloy Supral 2004. Such a transformation is characterized by significant retention of the deformation microstructure and texture. Microtexture analysis methods have been employed to examine the grain-boundary misorientation distribution in as-processed Supral 2004? and its evolution during annealing of this alloy. A bimodal boundary misorientation distribution is observed in as-processed material and is seen to persist through subsequent annealing. Comparison of correlated (nearest neighbour) with uncorrelated (predicted by the texture) grain-boundary misorientation data reveals tl-lat the populations of boundaries in the misorientation ranges of 0-15 degrees and 55-62.8 degrees exceed those predicted. ii model is presented describing high-angle boundaries as interfaces between symmetric variants of the deformation texture components. The misorientation distribution of lower-angle boundaries can be fitted by a probability density function. It is concluded that grain subdivision into deformation bands during severe straining leads to the formation of high-angle grain boundaries as interfaces between symmetric variants of deformation texture components, while lower-angle boundaries develop by dislocation reaction within these variants: leading to observed bimodal grain-boundary misorientation distributions. During post-processing static annealing, stable coarsening of deformation-induced features occurs gradually and homogeneously throughout the microstructure without recrystallization involving the formation of new grains by the migration of high-angle grain boundaries, The ability to quantify and model the reactions that occur during thermomechanical processing, and that lead to the microstructures present in Supral 2004, will facilitate processing for similar reactions in a wider family of aluminium alloys for enhanced formability. C1 USN, Postgrad Sch, Dept Mech Engn, Monterey, CA 93943 USA. Ctr Nacl Invest Met, Dept Met Fis, Madrid 28040, Spain. RP McNelley, TR (reprint author), USN, Postgrad Sch, Dept Mech Engn, 700 Dyer Rd, Monterey, CA 93943 USA. RI Perez-Prado, Maria Teresa/M-2050-2014 OI Perez-Prado, Maria Teresa/0000-0003-0758-2851 NR 32 TC 17 Z9 17 U1 1 U2 9 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 1364-503X J9 PHILOS T R SOC A JI Philos. Trans. R. Soc. A-Math. Phys. Eng. Sci. PD JUN 15 PY 1999 VL 357 IS 1756 BP 1683 EP 1705 PG 23 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 211HT UT WOS:000081155400020 ER PT J AU Hess, DW Serene, JW AF Hess, DW Serene, JW TI Quasiparticle band structure and density-functional theory: Single-particle excitations and band gaps in lattice models SO PHYSICAL REVIEW B LA English DT Article ID SOLVABLE SEMICONDUCTOR MODEL; EXCHANGE AB We compare the quasiparticle band structure for a model insulator obtained from the fluctuation exchange approximation (FEA) with the eigenvalues of the corresponding density-functional theory (DFT) and local-density approximation (LDA). The discontinuity in the exchange-correlation potential for this model is small; and the FEA and DFT band structures are in good agreement. In contrast to conventional wisdom, the LDA for this model overestimates the size of the band gap. We argue that this is a consequence of an FEA self-energy that is strongly frequency dependent, but essentially local. [S0163-1829(99)00123-X]. C1 USN, Res Lab, Ctr Computat Mat Sci, Washington, DC 20375 USA. Georgetown Univ, Dept Phys, Washington, DC 20057 USA. RP USN, Res Lab, Ctr Computat Mat Sci, Washington, DC 20375 USA. OI Serene, Joseph/0000-0002-3233-2531 NR 25 TC 2 Z9 2 U1 0 U2 1 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 JUN 15 PY 1999 VL 59 IS 24 BP 15617 EP 15624 DI 10.1103/PhysRevB.59.15617 PG 8 WC Physics, Condensed Matter SC Physics GA 210ZD UT WOS:000081134700011 ER PT J AU Fornari, M Singh, DJ AF Fornari, M Singh, DJ TI Prediction of room-temperature high-thermoelectric performance in n-type La(Ru1-xRhx)(4)Sb-12 SO APPLIED PHYSICS LETTERS LA English DT Article ID FILLED SKUTTERUDITE ANTIMONIDES AB First-principles calculations are used to investigate the band structure and the transport-related properties of unfilled and filled 4d skutterudite antimonides. The calculations show that, while RhSb3 and p-type La(Rh,Ru)(4)Sb-12 are unfavorable for thermoelectric application, n-type La(Rh,Ru)(4)Sb-12 is very likely a high figure-of-merit thermoelectric material in the important temperature range 150-300 K. (c) 1999 American Institute of Physics. [S0003-6951(99)00924-9]. C1 CSI George Mason Univ, Fairfax, VA 22030 USA. USN, Res Lab, Ctr Computat Mat Sci, Washington, DC 20375 USA. RP Fornari, M (reprint author), CSI George Mason Univ, Fairfax, VA 22030 USA. RI Fornari, Marco/C-8848-2012; Singh, David/I-2416-2012 OI Fornari, Marco/0000-0001-6527-8511; NR 14 TC 17 Z9 17 U1 1 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JUN 14 PY 1999 VL 74 IS 24 BP 3666 EP 3668 DI 10.1063/1.124220 PG 3 WC Physics, Applied SC Physics GA 202VB UT WOS:000080671900025 ER PT J AU Altschuler, EL Wisdom, SB Stone, L Foster, C Galasko, D Llewellyn, DME Ramachandran, VS AF Altschuler, EL Wisdom, SB Stone, L Foster, C Galasko, D Llewellyn, DME Ramachandran, VS TI Rehabilitation of hemiparesis after stroke with a mirror SO LANCET LA English DT Article C1 Univ Calif San Diego, Brain & Percept Lab, La Jolla, CA 92093 USA. USN, Med Ctr, Dept Neurosci, San Diego, CA 92134 USA. RP Altschuler, EL (reprint author), Univ Calif San Diego, Brain & Percept Lab, 9500 Gilman Dr,0190, La Jolla, CA 92093 USA. NR 5 TC 235 Z9 255 U1 3 U2 28 PU LANCET LTD PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 0140-6736 J9 LANCET JI Lancet PD JUN 12 PY 1999 VL 353 IS 9169 BP 2035 EP 2036 DI 10.1016/S0140-6736(99)00920-4 PG 2 WC Medicine, General & Internal SC General & Internal Medicine GA 205GD UT WOS:000080812200015 PM 10376620 ER PT J AU Freund, HP Granatstein, VL AF Freund, HP Granatstein, VL TI Long wavelength free-electron lasers in 1998 SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 20th International Free Electron Laser Conference 5th FEL User Workshop CY AUG 16-22, 1998 CL WILLIAMSBURG, VIRGINIA SP Duke Unvi, Dept of Energy USA, Thomas Jefferson Natl Accelerator Facil, Du Pont, Off Naval Res, SNC DE free-electron lasers; space-charge effect; wavelength ID AMPLIFIER; RADIATION; WIGGLER 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. For example, 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. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Maryland, College Pk, MD 20742 USA. RP Freund, HP (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 26 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 JUN 11 PY 1999 VL 429 IS 1-3 BP 33 EP 36 DI 10.1016/S0168-9002(99)00062-5 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 210WD UT WOS:000081126900008 ER PT J AU Colson, WB AF Colson, WB TI Short wavelength free electron lasers in 1998 SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 20th International Free Electron Laser Conference 5th FEL User Workshop CY AUG 16-22, 1998 CL WILLIAMSBURG, VIRGINIA SP Duke Unvi, Dept of Energy USA, Thomas Jefferson Natl Accelerator Facil, Du Pont, Off Naval Res, SNC ID TESLA-TEST-FACILITY; SPONTANEOUS-EMISSION; STORAGE-RING; VUV-FEL; SUPERCONDUCTING LINAC; RACETRACK MICROTRON; FIRST LASINGS; FELICITA-I; DESIGN; AMPLIFICATION AB A table is presented that describes the characteristics of 58 short wavelength free electron lasers, operating and proposed, around the world. 1999 Published by Elsevier Science B.V. C1 USN, Postgrad Sch, Dept Phys, Monterey, CA 93943 USA. RP Colson, WB (reprint author), USN, Postgrad Sch, Dept Phys, Monterey, CA 93943 USA. NR 54 TC 11 Z9 11 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 JUN 11 PY 1999 VL 429 IS 1-3 BP 37 EP 40 DI 10.1016/S0168-9002(99)00063-7 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 210WD UT WOS:000081126900009 ER PT J AU Freund, HP Jackson, RH Danly, BG Levush, B AF Freund, HP Jackson, RH Danly, BG Levush, B TI Power and bandwidth studies for W-band free-electron masers SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 20th International Free Electron Laser Conference 5th FEL User Workshop CY AUG 16-22, 1998 CL WILLIAMSBURG, VIRGINIA SP Duke Unvi, Dept of Energy USA, Thomas Jefferson Natl Accelerator Facil, Du Pont, Off Naval Res, SNC DE bandwidth; W-band; FEM amplifier; Gyro-klystron; waveguide ID GYROKLYSTRON AMPLIFIER; LASER-AMPLIFIER; PERFORMANCE; DESIGN; FIELD AB Power and bandwidth studies for a high power W-band (approximate to 94 GHz) FEM amplifier is presented for a helical wiggler/cylindrical waveguide configuration using 3D ARACHNE simulation code (H.P. Freund, T.M. Antonsen, Jr., Principles of Free-electron Lasers. 2nd edn., Chapman & Hall, London, 1996, Ch. 5). Using a 300 kV/20 A electron beam with a normalized emittance of 95 mm mrad, a 600 G wiggler field with a 0.88 cm period, and a strong guide field of 20 kG, efficiencies of greater than 8% are possible with a FWHM bandwidth of 4.5 GHz. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. Lucent Technol Inc, Norcross, GA 30071 USA. RP Freund, HP (reprint author), Sci Applicat Int Corp, 1710 Goodridge Dr, Mclean, VA 22102 USA. NR 18 TC 0 Z9 0 U1 0 U2 1 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 JUN 11 PY 1999 VL 429 IS 1-3 BP 70 EP 75 DI 10.1016/S0168-9002(99)00069-8 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 210WD UT WOS:000081126900015 ER PT J AU Taccetti, JM Jackson, RH Freund, HP Pershing, DE Granatstein, VL AF Taccetti, JM Jackson, RH Freund, HP Pershing, DE Granatstein, VL TI A Ka-band CHI-wiggler free-electron maser: experimental results SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 20th International Free Electron Laser Conference 5th FEL User Workshop CY AUG 16-22, 1998 CL WILLIAMSBURG, VIRGINIA SP Duke Unvi, Dept of Energy USA, Thomas Jefferson Natl Accelerator Facil, Du Pont, Off Naval Res, SNC DE coaxial; wiggler; microwaves; free-electron maser; small-period wigglers AB Due to the nature of the Coaxial Hybrid Iron wiggler, a resonance between the transverse wiggler and cyclotron motions of the beam exists which can enhance the Free-Electron Maser interaction. The difference in behavior on either side of this resonance is presented. Amplification with a bandwidth on the order of a few percent was achieved. In spite of beam propagation problems, the gain was about 5 dB for operation below gyroresonance, and 7 dB above it, when wideband grazing intersection operation was achieved. A gain as high as 13.5 dB was obtained for cutting intersection between the beam line and the TE01 dispersion curve. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. USN, Res Lab, Washington, DC 20375 USA. Sci Applicat Int Corp, Mclean, VA 22102 USA. MRC, Newington, VA 22122 USA. Univ Maryland, College Pk, MD 20742 USA. RP Taccetti, JM (reprint author), Univ Calif Los Alamos Natl Lab, MS E526, Los Alamos, NM 87545 USA. NR 6 TC 8 Z9 8 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 JUN 11 PY 1999 VL 429 IS 1-3 BP 116 EP 120 DI 10.1016/S0168-9002(99)00083-2 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 210WD UT WOS:000081126900023 ER PT J AU Summers, ME AF Summers, ME TI Atmospheric science - Vertical couplings SO SCIENCE LA English DT Editorial Material ID HALOGEN OCCULTATION EXPERIMENT; MIDDLE ATMOSPHERE; OZONE C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Summers, ME (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. NR 11 TC 1 Z9 1 U1 0 U2 0 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD JUN 11 PY 1999 VL 284 IS 5421 BP 1783 EP + DI 10.1126/science.284.5421.1783 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 205EU UT WOS:000080809000036 ER PT J AU Janoff, EN Tasker, SA Stevenson, M Rubins, JB O'Brien, J Utz, G Weiss, P Hall, FW Wallace, MR AF Janoff, EN Tasker, SA Stevenson, M Rubins, JB O'Brien, J Utz, G Weiss, P Hall, FW Wallace, MR TI Immune activation and virologic response to immunization in recent HIV type 1 seroconverters SO AIDS RESEARCH AND HUMAN RETROVIRUSES LA English DT Article ID IMMUNODEFICIENCY-VIRUS INFECTION; INVASIVE PNEUMOCOCCAL DISEASE; CD4(+) T-CELLS; VIRAL LOAD; INFLUENZA VACCINATION; REPLICATION; TUBERCULOSIS; PROGRESSION; BACTEREMIA; VIREMIA AB Antigenic stimulation from invasive bacterial infections, and the vaccines designed to prevent them, may promote T cell activation and enhancement of HIV-1 replication. Changes in viral load have been correlated with antigen-specific responses. We prospectively determined the impact of immunization with 23-valent pneumococcal vaccine (PVAX) and Haemophilus influenzae type b (Hib)-modified diphtheria toroid CRM197 (DT) vaccine on HIV-1 replication in recent HIV-1 seroconverters (n = 14; median, 5.5 months from infection; median CD4(+) T cells, 535 mu l), and correlated results with vaccine-related immune activation. Specific antibody responses, markers of CD4(+) T cell activation (transferrin and interleukin 2 receptors), and viral burden were measured at weeks -2 (pre), 0, 1, 2, 6, and 12 after immunization. By week 2, levels of IgG had increased significantly over baseline in both HIV-1-infected patients and HIV-1-seronegative control subjects (n = 9) for each antigen (geometric mean fold rise: PVAX, 10.1 versus 5.3; Dib, 16.0 versus 11.7; and DT, 26.2 versus 24.5, respectively). Despite these vigorous responses to both polysaccharide and protein antigens, HIV-1-infected patients showed limited evidence of CD4(+) T cell activation at 1 week, no consistent rise in HIV-1 burden at any point, and no decline in CD4(+) T cell number over time. We conclude that recent HIV-1 seroconverters show vigorous humoral responses to vaccine antigens and limited early evidence of T cell activation, but no substantial or sustained increase in viral replication or decline in CD4(+) T cell number. Thus, respiratory bacterial vaccines appear immunogenic and safe early in HIV-1 infection. C1 Vet Affairs Med Ctr, Infect Dis Sect 111F, Dept Med, Minneapolis, MN 55417 USA. USN Hosp, Dept Infect Dis, San Diego, CA 92134 USA. Univ Massachusetts, Med Ctr, Program Mol Med, Worcester, MA 01605 USA. Vet Affairs Med Ctr, Dept Med, Pulm Sect, Minneapolis, MN 55417 USA. USN Hosp, Dept Pathol, San Diego, CA 92134 USA. RP Janoff, EN (reprint author), Vet Affairs Med Ctr, Infect Dis Sect 111F, Dept Med, 1 Vet Dr, Minneapolis, MN 55417 USA. FU NHLBI NIH HHS [HL96008]; NIAID NIH HHS [AI31373, AI39445] NR 57 TC 12 Z9 12 U1 0 U2 0 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 USA SN 0889-2229 J9 AIDS RES HUM RETROV JI Aids Res. Hum. Retrovir. PD JUN 10 PY 1999 VL 15 IS 9 BP 837 EP 845 DI 10.1089/088922299310746 PG 9 WC Immunology; Infectious Diseases; Virology SC Immunology; Infectious Diseases; Virology GA 204UZ UT WOS:000080784100007 PM 10381172 ER PT J AU Feldman, U Doschek, GA Schuhle, U Wilhelm, K AF Feldman, U Doschek, GA Schuhle, U Wilhelm, K TI Properties of quiet-Sun coronal plasmas at distances of 1.03 <= R-circle dot <= 1.50 along the solar equatorial plane SO ASTROPHYSICAL JOURNAL LA English DT Article DE diffusion; Sun : abundances; Sun : corona; Sun : fundamental parameters; Sun : UV radiation ID SUMER TELESCOPE; SPECTROMETER; SOHO; SPECTRA; LINES AB We determine the physical properties, i.e., electron temperature, density, line-of-sight emission measure, and element-abundance variation with height, in the Sun's equatorial west limb streamer region from extreme-ultraviolet (EUV) spectra recorded by the Solar Ultraviolet Measurements of Emitted Radiation (SUMER) spectrometer on the Solar and Heliospheric Observatory (SOHO) spacecraft. The spectra were recorded on 1996 November 21-22 during a special "roll" maneuver in which the SUMER slit was oriented in the east-west direction. Because the SUMER spectrometer is stigmatic along the slit length, the spectra are spatially resolved in the east-west direction. The spectra we discuss cover an effective distance range outside the west limb from 1.03 to 1.50 solar radii (R.); the maximum spatial resolution is 1 ". We select a group of emission lines for analysis that under the usual ionization equilibrium assumption span the temperature range from 3 x 10(5) up to 2 x 10(6) K. However, we note that above the limb a major fraction of a line intensity may arise at a temperature that is far from the temperature of maximum emitting efficiency in ionization equilibrium. In this paper we assume ionization equilibrium in deriving plasma parameters. Readers can redo our analysis without this assumption if desired, because the line intensities we present in this paper are simply the measured photon production rates in the lines. Assuming ionization equilibrium, we determine the electron temperature, electron density, line-of-sight emission measure, and abundance variation with height above the limb from the line intensities and line intensity ratios. The spatial resolution has allowed us to detect an apparent element-abundance variation as a function of height above the west limb that is strong evidence for gravitational settling of " heavy" elements. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Max Planck Inst Aeron, D-37191 Katlenburg Lindau, Germany. RP Feldman, U (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. NR 21 TC 93 Z9 93 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUN 10 PY 1999 VL 518 IS 1 BP 500 EP 507 DI 10.1086/307252 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 211JZ UT WOS:000081158600042 ER PT J AU Dennis, ML Kaechele, WI Goldberg, L Carruthers, TF Duling, IN AF Dennis, ML Kaechele, WI Goldberg, L Carruthers, TF Duling, IN TI Wavelength-division multiplexing of adiabatic solitons for repeaterless transmission SO ELECTRONICS LETTERS LA English DT Article ID WDM TRANSMISSION; FIBER AB Error-free repeaterless transmission of two 10Gbit/s wavelength-division multiplexed channels over 236km using adiabatic soliton propagation has been demonstrated. The 150GHz optical bandwidth of each channel is converted by the adiabatic evolution to 12.5GHz, allowing dense wavelength multiplexing. Channel separations of 100 and 675GHz are compared. C1 USN, Res Lab, Adv Lightwave Applicat Sect, Washington, DC 20375 USA. RP Dennis, ML (reprint author), USN, Res Lab, Adv Lightwave Applicat Sect, Code 5654, Washington, DC 20375 USA. NR 10 TC 0 Z9 0 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 10 PY 1999 VL 35 IS 12 BP 1003 EP 1004 DI 10.1049/el:19990709 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA 213QM UT WOS:000081284800040 ER PT J AU McKeown, DA Hagans, PL Carette, LPL Russell, AE Swider, KE Rolison, DR AF McKeown, DA Hagans, PL Carette, LPL Russell, AE Swider, KE Rolison, DR TI Structure of hydrous ruthenium oxides: Implications for charge storage SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID ABSORPTION FINE-STRUCTURE; ELECTROCHEMICAL CAPACITORS; ELECTRICAL-PROPERTIES; DIOXIDE; AEROGELS; OXYGEN AB Hydrous ruthenium oxide (RuO2. H2O or RuOxHy) is a mixed electron-proton conductor with a specific capacitance as high as 720 F/g/proton, making it a candidate material for energy storage. The correlation between the structure and properties of RuO2. xH(2)O materials is not well understood due to their amorphous nature and compositional variability. In this study, ruthenium oxides with the compositions RuO2. 2.32H(2)O RuO2. 0.29H(2)O, and anhydrous RuO2 are characterized using thermogravimetric analysis (TGA), X-ray diffraction (XRD), and X-ray absorption near-edge structure (XANES) and extended X-ray fine structure (EXGFS) analyses. XANES cannot be used to distinguish between Ru(III) and Ru(IV) in the hydrous oxides, but the EXAFS analyses show large differences in the short-range structures of the materials. Whereas anhydrous RuO2 has the rutile structure comprising chains of RuO6 octahedra linked in three dimensions, the structure of RuO2. 0.29H(2)O is rutile-like at the RuO6 core, but less connected and progressively disordered beyond the RuO6 core. The structure of RuO2. 2.32H(2)O is composed of chains of disordered RuO6 octahedra that exhibit no chain-to-chain linking or three-dimensional order. Although the local structures of RuO2. 0.29H(2)O and RuO2. 2.32H(2)O markedly differ, their specific capacitances are large and essentially equivalent, so nonunique local structures can balance effective electron transport (along dioxo bridges) with the effective proton transport (through structural water) necessary for charge storage. C1 USN, Res Lab, Surface Chem Branch, Washington, DC 20375 USA. Catholic Univ Amer, Vitreous State Lab, Washington, DC 20069 USA. Univ Southampton, Dept Chem, Southampton SO17 1BJ, Hants, England. RP Rolison, DR (reprint author), USN, Res Lab, Surface Chem Branch, 6170, Washington, DC 20375 USA. RI Russell, Andrea/B-8114-2009; Russell, Andrea/A-9625-2012 NR 33 TC 268 Z9 270 U1 11 U2 78 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JUN 10 PY 1999 VL 103 IS 23 BP 4825 EP 4832 DI 10.1021/jp990096n PG 8 WC Chemistry, Physical SC Chemistry GA 206YL UT WOS:000080908100007 ER PT J AU Todorov, SS Bu, H Boyd, KJ Rabalais, JW Gilmore, CM Sprague, JA AF Todorov, SS Bu, H Boyd, KJ Rabalais, JW Gilmore, CM Sprague, JA TI Ion beam deposition of Ag-107(111) films on Ni(100) SO SURFACE SCIENCE LA English DT Article DE ion beam deposition; ion scattering; nickel; silver films ID INCOMMENSURATE OVERLAYERS; FCC METALS; LOW-ENERGY; AG; SCATTERING; DYNAMICS; SPECTROMETRY AB Monolayer thick silver films were grown on an Ni(100) surface using direct ion beam deposition of Ag-107(+) ions with 20 eV kinetic energy and the substrate at 25 degrees C. Deposition was performed by means of a mass-selected, low-energy, ultra-high vacuum ion beam system with a well-defined ion energy. The films were analyzed in situ by time-of-flight scattering and recoiling spectrometry (TOF-SARS) and by low energy electron diffraction (LEED). Classical ion trajectory simulations were used to model the TOF-SARS spectra. Results of the TOF-SARS spectra and azimuthal scans are consistent with the growth of a monolayer Ag film with a fcc (111) structure on the Ni(100) surface. The deposited films exhibited a faint hexagonal c(2 x 8) LEED pattern. Molecular dynamic simulations of the deposition process are in agreement with the experimental observations. The growth of such isotopically pure metal monolayers at room temperature with controlled orientations provides the opportunity for exploring a variety of unique physical properties, (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Houston, Dept Chem, Houston, TX 77204 USA. George Washington Univ, Inst Sci Mat, Washington, DC 20016 USA. USN, Res Lab, Surface Modificat Branch, Washington, DC 20375 USA. RP Rabalais, JW (reprint author), Univ Houston, Dept Chem, Univ Pk, Houston, TX 77204 USA. NR 19 TC 5 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD JUN 10 PY 1999 VL 429 IS 1-3 BP 63 EP 70 DI 10.1016/S0039-6028(99)00339-8 PG 8 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 209FH UT WOS:000081037200017 ER PT J AU Duan, X Linder, DP Page, M Soto, MR AF Duan, X Linder, DP Page, M Soto, MR TI Structures and thermochemistry of BHlFm(OH)(n) and several XYBO compounds at the G-2 level of theory SO JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM LA English DT Article DE ab initio; thermochemistry; boron compounds ID MOLECULAR-ENERGIES; 2ND-ROW COMPOUNDS; GAUSSIAN-2 THEORY; KINETIC-MODEL; AB-INITIO; BORON; COMBUSTION; CHEMISTRY; SYSTEM AB The heats of formation of BHlFm(OH)(n), with I,m,n = 0-3 and selected XYBO compounds with X,Y = H, OH, or F have been computed at the GAUSSIAN-2 level Of theory. An rms deviation of 1.5 kcal/mol is found between the computed heats of formation and experiment for the following five BXYZ compounds with well known thermochemistry: BH3, BF3, B(OH)(3), BHF2, and BF2(OH). Heats of formation are presented for 33 other species for which experimental thermochemistry is unavailable or unreliable. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 N Dakota State Univ, Dept Chem, Ctr Main Grp Chem, Fargo, ND 58105 USA. USN, Res Lab, Lab Computat Phys, Washington, DC 20375 USA. RP Page, M (reprint author), N Dakota State Univ, Dept Chem, Ctr Main Grp Chem, Fargo, ND 58105 USA. NR 41 TC 16 Z9 16 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-1280 J9 J MOL STRUC-THEOCHEM JI Theochem-J. Mol. Struct. PD JUN 8 PY 1999 VL 465 IS 2-3 BP 231 EP 242 DI 10.1016/S0166-1280(99)00059-7 PG 12 WC Chemistry, Physical SC Chemistry GA 200CR UT WOS:000080522500013 ER PT J AU Kim, H Pique, A Horwitz, JS Mattoussi, H Murata, H Kafafi, ZH Chrisey, DB AF Kim, H Pique, A Horwitz, JS Mattoussi, H Murata, H Kafafi, ZH Chrisey, DB TI Indium tin oxide thin films for organic light-emitting devices SO APPLIED PHYSICS LETTERS LA English DT Article ID OPTICAL-PROPERTIES; FABRICATION; EVAPORATION; DEPOSITION AB High-quality indium tin oxide (ITO) thin films (150-200 nm) were grown on glass substrates by pulsed laser deposition (PLD) without postdeposition annealing. The electrical, optical, and structural properties of these films were investigated as a function of substrate temperature, oxygen pressure, and film thickness. PLD provides very uniform ITO films with high transparency (greater than or equal to 85% in 400-700 nm spectrum) and low electrical resistivity (2 - 4 x 10(-4) Omega cm). The Hall mobility and carrier density for a 170-nm-thick film deposited at 300 degrees C are 29 cm(2)/V s and 1.45 x 10(21) cm(-3), respectively. Atomic force microscopy measurements of the ITO films indicated that their root-mean-square surface roughness (similar to 5 Angstrom) is superior to that (similar to 40 Angstrom) of commercially available ITO films deposited by sputtering. ITO films grown at room temperature by PLD were used to study the electroluminescence (EL) performance of organic light-emitting devices. The EL performance was comparable to that measured with commercial ITO anodes. (C) 1999 American Institute of Physics. [S0003-6951(99)00123-0]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Kim, H (reprint author), George Washington Univ, Sch Engn & Appl Sci, Inst Sci Mat, Washington, DC 20052 USA. RI Murata, Hideyuki/J-8453-2012 OI Murata, Hideyuki/0000-0001-8248-9652 NR 14 TC 265 Z9 273 U1 2 U2 69 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JUN 7 PY 1999 VL 74 IS 23 BP 3444 EP 3446 DI 10.1063/1.124122 PG 3 WC Physics, Applied SC Physics GA 200BL UT WOS:000080519000006 ER PT J AU Friedman, M Fernsler, RF AF Friedman, M Fernsler, RF TI Guiding radio frequency waves on metallic foils SO APPLIED PHYSICS LETTERS LA English DT Article AB The propagation of electromagnetic surface waves along thin metallic strips was investigated. Efficient guidance of surface waves over distances of many kilometers can now be realized since: (1) low attenuation of the electromagnetic waves can be achieved by increasing the width of the strip, (2) losses by scattering are small because of the large reduction in the radial extension of the electric field, and (3) thin foils are lightweight. Other means (e.g., coaxial line or waveguides! of transporting electromagnetic waves produce orders of magnitude increase in weight, cost, and attenuation. (C) 1999 American Institute of Physics. [S0003-6951(99)01523-5]. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. RP Friedman, M (reprint author), USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. NR 10 TC 2 Z9 2 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JUN 7 PY 1999 VL 74 IS 23 BP 3468 EP 3470 DI 10.1063/1.124130 PG 3 WC Physics, Applied SC Physics GA 200BL UT WOS:000080519000014 ER PT J AU Gammaitoni, L Locher, M Bulsara, A Hanggi, P Neff, J Wiesenfeld, K Ditto, W Inchiosa, ME AF Gammaitoni, L Locher, M Bulsara, A Hanggi, P Neff, J Wiesenfeld, K Ditto, W Inchiosa, ME TI Controlling stochastic resonance SO PHYSICAL REVIEW LETTERS LA English DT Article ID BISTABLE SYSTEM; NOISE AB We introduce an open-loop control scheme for stochastic resonators; the scheme permits the enhancement or suppression of the spectral response to threshold-crossing events triggered by a time-periodic signal in background noise. The control is demonstrated in experiments using a Schmitt trigger. A generic two-state theory captures the essential features observed in our experiments and in numerical simulations; this suggests the generality of the effect. [S0031-9007(99)09258-3]. C1 Univ Perugia, Dipartimento Fis, I-06100 Perugia, Italy. Ist Nazl Fis Nucl, Sezione Perugia, I-06100 Perugia, Italy. USN, Space & Naval Warfare Syst Ctr, San Diego, CA 92152 USA. Univ Augsburg, Inst Phys, Lehrstuhl Theoret Phys 1, D-86135 Augsburg, Germany. Georgia Inst Technol, Sch Phys, Atlanta, GA 30332 USA. RP Gammaitoni, L (reprint author), Univ Perugia, Dipartimento Fis, I-06100 Perugia, Italy. RI Gammaitoni, Luca/B-5375-2009; Hanggi, Peter/B-4457-2008; OI Gammaitoni, Luca/0000-0002-4972-7062; Ditto, William/0000-0002-7416-8012 NR 22 TC 117 Z9 120 U1 2 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 JUN 7 PY 1999 VL 82 IS 23 BP 4574 EP 4577 DI 10.1103/PhysRevLett.82.4574 PG 4 WC Physics, Multidisciplinary SC Physics GA 202ZK UT WOS:000080682300002 ER PT J AU Buckley, RG Distefan, J Gubler, KD Slymen, D AF Buckley, RG Distefan, J Gubler, KD Slymen, D TI The risk of appendiceal rupture based on hospital admission source SO ACADEMIC EMERGENCY MEDICINE LA English DT Article DE appendicitis; appendiceal rupture; admission source; risk factors; emergency department ID INSURANCE-RELATED DIFFERENCES; CHILDHOOD APPENDICITIS; PERFORATION RATE; AGE; APPENDECTOMY; DIAGNOSIS; MORBIDITY; EMERGENCY; ACCURACY; CHILDREN AB Objective: To determine whether admission source is a-potential risk factor for appendiceal rupture. Methods: Administrative data were obtained from the California Office of Statewide Health Planning and Development for all patients in San Diego County with, the primary diagnosis of appendicitis:during 1993. The appendiceal rupture ratio was defined as those coded as ruptured (ICD-9-CM codes 540.0 and 540.1) divided by both ruptured and nonruptured cases (540.9). The odds ratio of appendiceal; rupture from routine outpatient, office or clinic venues vs those admitted through the ED were calculated using multivariate logistic regression analysis to adjust for age, sex, race, comorbidity, insurance status, and home address to hospital proximity. Results: There were a total of 1,906 patients, of whom 663 (34.8%) had appendiceal ruptures. Of the 1,360 (71.4%) admitted from the ED, 422(31.0%) had ruptures, compared with 211 (43.3%) of the 487 admitted from outpatient sources (p < 0.0001). Patients with appendicitis directly admitted from outpatient sources were more likely to be complicated by appendiceal rupture than were those admitted through the hospital ED (adjusted odds ratio 1.62, 95% CI = 1.28 to 2.05, p < 0.0001). Conclusion: Patients with appendicitis admitted from outpatient sources are more likely to have appendiceal rupture than are those admitted from the ED. C1 USN, Med Ctr, Dept Clin Res, San Diego, CA 92134 USA. USN, Med Ctr, Dept Emergency Med, San Diego, CA 92152 USA. USN, Med Ctr, Dept Surg, San Diego, CA 92152 USA. San Diego State Univ, Grad Sch Publ Hlth, Div Epidemiol & Biostat, San Diego, CA 92182 USA. RP Buckley, RG (reprint author), USN, Med Ctr, Dept Clin Res, 34800 Bob Wilson Dr,Suite 5, San Diego, CA 92134 USA. NR 37 TC 14 Z9 14 U1 0 U2 0 PU HANLEY & BELFUS INC PI PHILADELPHIA PA 210 S 13TH ST, PHILADELPHIA, PA 19107 USA SN 1069-6563 J9 ACAD EMERG MED JI Acad. Emerg. Med. PD JUN PY 1999 VL 6 IS 6 BP 596 EP 601 DI 10.1111/j.1553-2712.1999.tb00412.x PG 6 WC Emergency Medicine SC Emergency Medicine GA 206EH UT WOS:000080864000006 PM 10386676 ER PT J AU Butler, EG AF Butler, EG TI Peripartum emergencies SO AMERICAN FAMILY PHYSICIAN LA English DT Letter C1 USN Hosp, Dept Family Practice, Jacksonville, FL 32214 USA. RP Butler, EG (reprint author), USN Hosp, Dept Family Practice, 2080 Child St, 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 USA SN 0002-838X J9 AM FAM PHYSICIAN JI Am. Fam. Physician PD JUN PY 1999 VL 59 IS 11 BP 2989 EP 2990 PG 2 WC Primary Health Care; Medicine, General & Internal SC General & Internal Medicine GA 205XG UT WOS:000080845700007 PM 10392586 ER PT J AU Culham, P AF Culham, P TI Blood in the arena: The spectacle of Roman power. SO AMERICAN HISTORICAL REVIEW LA English DT Book Review C1 USN Acad, Annapolis, MD 21402 USA. RP Culham, P (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER HISTORICAL REVIEW PI WASHINGTON PA 400 A ST SE, WASHINGTON, DC 20003 USA SN 0002-8762 J9 AM HIST REV JI Am. Hist. Rev. PD JUN PY 1999 VL 104 IS 3 BP 969 EP 970 DI 10.2307/2651100 PG 2 WC History SC History GA 209GX UT WOS:000081040800121 ER PT J AU Magann, EF Chauhan, SP Kinsella, MJ McNamara, MF Whitworth, NS Morrison, JC AF Magann, EF Chauhan, SP Kinsella, MJ McNamara, MF Whitworth, NS Morrison, JC TI Antenatal testing among 1001 patients at high risk: The role of ultrasonographic estimate of amniotic fluid volume SO AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY LA English DT Article; Proceedings Paper CT 66th Annual Meeting of the Central-Association-of-Obstetricians-and-Gynecologists CY OCT 15-17, 1998 CL KANSAS CITY, MISSOURI SP Cent Assoc Obstetricians & Gynecologists DE 2-diameter pocket; amniotic fluid index; pregnancy outcome ID OLIGOHYDRAMNIOS; PREGNANCY; INDEX AB OBJECTIVE: Our goal was to compare the accuracy of the amniotic fluid index and the 2-diameter pocket technique with respect to accuracy in predicting an adverse pregnancy outcome among patients at high risk undergoing antenatal testing. STUDY DESIGN: All women with high-risk pregnancies and intact membranes who underwent antenatal testing during an 18-month period were prospectively enrolled. Ultrasonographic estimates of amniotic fluid volume were performed by means of the amniotic fluid index and the 2-diameter pocket technique. Relative risks with 95% confidence intervals and receiver operator characteristic curves were calculated for patients with an ultrasonographic estimate of oligohydramnios (amniotic fluid index of less than or equal to 5 cm or 2-diameter pocket of less than or equal to 15 cm(2)) versus normal fluid level (amniotic fluid index of >5 cm or 2-diameter pocket of >15 cm(2)). Outcome variables studied were intrapartum and neonatal complications. RESULTS: Among 1001 patients the mean (+/-SD) amniotic fluid index was 10.5 +/- 5 cm and the mean (+/-SD) 2-diameter pocket was 18.7 +/- 13.6 cm(2). Significantly more patients (46%) were considered to have oligohy dramnios according to the 2-diameter pocket criteria than according to the amniotic fluid index (21%, P <.0001, relative risk 1.7, 95% confidence interval 1.5-1.8). No significant differences in the incidences of nonreactive nonstress test results, meconium-stained amniotic fluid, cesarean delivery for fetal distress, low Apgar scores, or infants with cord pH of <7.10 were observed between the oligohydramnios and normal amniotic fluid groups (P>.05) when assessed by relative risk with confidence interval and by receiver operator characteristic curves. CONCLUSIONS: Current ultrasonographic measurements with the amniotic fluid index and the 2-diameter pocket technique are poor diagnostic tests to determine whether a patient is at high risk for an adverse peri natal outcome. C1 USN, Ctr Med, Dept Obstet & Gynecol, San Diego, CA 92152 USA. Med Coll Georgia, Augusta, GA 30912 USA. Univ Mississippi, Med Ctr, Jackson, MS 39216 USA. RP Magann, EF (reprint author), USN, Ctr Med, Dept Obstet & Gynecol, San Diego, CA 92152 USA. NR 20 TC 47 Z9 51 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0002-9378 J9 AM J OBSTET GYNECOL JI Am. J. Obstet. Gynecol. PD JUN PY 1999 VL 180 IS 6 BP 1330 EP 1334 DI 10.1016/S0002-9378(99)70015-3 PN 1 PG 5 WC Obstetrics & Gynecology SC Obstetrics & Gynecology GA 210CU UT WOS:000081088200004 PM 10368467 ER PT J AU Magann, EF Kinsella, MJ Chauhan, SP McNamara, MF Gehring, BW Morrison, JC AF Magann, EF Kinsella, MJ Chauhan, SP McNamara, MF Gehring, BW Morrison, JC TI Does an amniotic fluid index of <= 5 cm necessitate delivery in high-risk pregnancies? A case-control study SO AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY LA English DT Article; Proceedings Paper CT 66th Annual Meeting of the Central-Association-of-Obstetricians-and-Gynecologists CY OCT 15-17, 1998 CL KANSAS CITY, MISSOURI SP Cent Assoc Obstetricians & Gynecologists DE amniotic fluid index; high-risk pregnancy; oligohydramnios ID 4-QUADRANT ASSESSMENT; PERINATAL MORBIDITY; VOLUME; OLIGOHYDRAMNIOS; INTRAPARTUM AB OBJECTIVE: This study was undertaken to determine whether women with high-risk pregnancies and an amniotic fluid index of less than or equal to 5 cm require labor induction to prevent adverse perinatal outcomes. STUDY DESIGN: All women at high risk at greater than or equal to 34 weeks' gestation with an amniotic fluid index of less than or equal to 5 cm were admitted to the hospital for labor induction. Each woman was compared with the next patient at high risk seen with an amniotic fluid index of >5 cm and the same pregnancy complication. Case patients were also matched with control subjects for maternal race, age, parity, and gestational age. RESULTS: Prospectively, 79 women at high risk with an amniotic fluid index of less than or equal to 5 cm were compared with 79 control subjects. There were no statistically significant differences between the 2 groups in the risks of thick meconium (P=.29), variable decelerations (moderate P=.27, severe P=.37), amnioinfusion (P=.37), cesarean delivery for fetal distress (P=.4), and umbilical artery pH <7.10 (P=.29). CONCLUSION: High-risk pregnancies with an amniotic fluid index of less than or equal to 5 cm appear to carry intrapartum complication rates similar to those of similar high-risk pregnancies with an amniotic fluid index of >5. C1 USN, Med Ctr, Dept Obstet & Gynecol, San Diego, CA 92152 USA. Med Coll Georgia, Dept Obstet & Gynecol, Augusta, GA 30912 USA. Univ Mississippi, Med Ctr, Dept Obstet & Gynecol, Jackson, MS 39216 USA. RP Magann, EF (reprint author), USN, Med Ctr, Dept Obstet & Gynecol, San Diego, CA 92152 USA. NR 20 TC 39 Z9 43 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0002-9378 J9 AM J OBSTET GYNECOL JI Am. J. Obstet. Gynecol. PD JUN PY 1999 VL 180 IS 6 BP 1354 EP 1358 DI 10.1016/S0002-9378(99)70019-0 PN 1 PG 5 WC Obstetrics & Gynecology SC Obstetrics & Gynecology GA 210CU UT WOS:000081088200012 PM 10368471 ER PT J AU Larson, GE Perry, ZA AF Larson, GE Perry, ZA TI Visual capture and human error SO APPLIED COGNITIVE PSYCHOLOGY LA English DT Article ID WORKING-MEMORY; ATTENTION; ACCIDENTS AB We investigated relationships between everyday error rates, susceptibility to stimulus-driven (i.e. external) capture of visual attention and working memory. Using an eye-tracking task called the antisaccade paradigm, we found that relatively error-prone subjects made significantly more unintended, stimulus-driven eye movements. This finding suggests a link between error-proneness and a tendency towards environmental (versus volitional) control of behaviour. No evidence was found for a connection between working memory capacity and error proneness or eye movements, though range restriction may have affected the working memory results. The findings are compatible with the view that some mishaps stem from environmental capture and triggering of inappropriate actions, and that individuals vary in their susceptibility to capture. Some implications are that: (1) mishaps might be reduced by redesigning tasks to reduce capture errors, e.g. by restructuring critical tasks to eliminate action sequences with common initial stages; (2) the antisaccade task may be a useful dependent measure in research on how stressors (e.g. fatigue, noise, temperature) increase the likelihood of mishaps. Specifically, since antisaccade performance was correlated with reports of real-world mistakes in the current study, antisaccade scores may allow useful predictions about how accident probability varies as a function of different conditions. Copyright (C) 1999 John Wiley & Sons, Ltd. C1 Naval Hlth Res Ctr, San Diego, CA 92186 USA. RP Larson, GE (reprint author), Naval Hlth Res Ctr, POB 85122, San Diego, CA 92186 USA. NR 19 TC 9 Z9 9 U1 0 U2 0 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0888-4080 J9 APPL COGNITIVE PSYCH JI Appl. Cogn. Psychol. PD JUN PY 1999 VL 13 IS 3 BP 227 EP 236 DI 10.1002/(SICI)1099-0720(199906)13:3<227::AID-ACP563>3.0.CO;2-J PG 10 WC Psychology, Experimental SC Psychology GA 220LQ UT WOS:000081667800004 ER PT J AU Zacharias, N Zacharias, MI De Vegt, C AF Zacharias, N Zacharias, MI De Vegt, C TI The second Cape Photographic Catalogue on the Hipparcos system SO ASTRONOMICAL JOURNAL LA English DT Article DE astrometry; catalogs ID CPC2; ADJUSTMENT AB The Second Cape Photographic Catalogue (CPC2) is an astrometric, photographic catalog covering the entire Southern Hemisphere to a limiting magnitude of about 10.5. The Hipparcos Catalogue has been used for a new, plate-by-plate, rigorous reduction. A significant improvement over the release 1 version of the data was achieved. With an average accuracy of 53 mas and a mean epoch of 1968, the CPC2 is a key catalog for proper-motion determination. This release 2 of the CPC2 contains high-quality positions of 266,629 stars and an appendix of 8040 other stars. Catalog reduction and construction details are given, as well as a description of the final product, which is available from the US Naval Observatory. C1 USN Observ, Washington, DC 20392 USA. Univ Hamburg, Hamburger Sternwarte, D-21029 Hamburg, Germany. Univ Space Res Assoc, Washington, DC USA. RP Zacharias, N (reprint author), USN Observ, 3450 Massachusetts Ave NW, Washington, DC 20392 USA. NR 17 TC 9 Z9 9 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD JUN PY 1999 VL 117 IS 6 BP 2895 EP 2901 DI 10.1086/300898 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 214VU UT WOS:000081348900026 ER PT J AU Stassun, KG Mathieu, RD Mazeh, T Vrba, FJ AF Stassun, KG Mathieu, RD Mazeh, T Vrba, FJ TI The rotation period distribution of pre-main-sequence stars in and around the Orion Nebula SO ASTRONOMICAL JOURNAL LA English DT Article DE stars : evolution; stars : pre-main-sequence; stars : rotation; stars : spots ID T-TAURI STARS; EMISSION-LINE STARS; LOW-MASS STARS; MAGNETOCENTRIFUGALLY DRIVEN FLOWS; ANGULAR-MOMENTUM EVOLUTION; MAGNETIC NEUTRON STARS; YOUNG STELLAR OBJECTS; SOLAR-TYPE STARS; MAGNETOSPHERIC ACCRETION; CIRCUMSTELLAR DISKS AB We report rotation periods for 254 stars in an area 40' x 80' centered on the Orion Nebula. We show that these stars are likely members of the young (similar to 10(6) yr) Orion OBIc/d association. The rotation period distribution we determine, which is sensitive to periods 0.1 < P < 8 days, shows a sharp cutoff for periods P < 0.5 days, corresponding to breakup velocity for these stars. Above 0.5 days the distribution is consistent with a uniform distribution; we do not find evidence for a "gap" of periods at 4-5 days. We find signatures of active accretion among stars at all periods; active accretion does not occur preferentially among slow rotators in our sample. We find no correlation between rotation period and near-IR signatures of circumstellar disks. In addition, we show that the distribution of nu sin i among stars in our sample bears striking resemblance to that of low-mass Pleiades stars. We discuss the implications of our findings for the evolution of stellar angular momentum during the pre-main-sequence phase. We argue that all stars in our sample must still deplete angular momentum by factors of roughly 5-10, if they are to preserve their nu sin i distribution over approximately the next 100 Myr. We consider in detail whether our findings are consistent with disk-regulated stellar rotation. We do not find observational evidence that magnetic disk-locking is the dominant mechanism in angular momentum evolution during the pre-main-sequence phase. C1 Univ Wisconsin, Dept Astron, Madison, WI 53706 USA. Tel Aviv Univ, Wise Observ, IL-69978 Tel Aviv, Israel. USN Observ, Flagstaff Stn, Flagstaff, AZ 86002 USA. RP Stassun, KG (reprint author), Univ Wisconsin, Dept Astron, 475 N Charter St, Madison, WI 53706 USA. NR 83 TC 203 Z9 203 U1 1 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD JUN PY 1999 VL 117 IS 6 BP 2941 EP 2979 DI 10.1086/300881 PG 39 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 214VU UT WOS:000081348900030 ER PT J AU Sterling, AC AF Sterling, AC TI Electron temperatures of a late-phase solar active region from Yohkoh BCS and SXT observations SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE Sun : atmosphere; Sun : corona; Sun : X-rays, gamma rays ID BRAGG CRYSTAL SPECTROMETER; X-RAY JETS; CORONAL LOOPS; EMISSION; FLARES; DYNAMICS; SPECTRA; SULFUR; LINES; MODEL AB We deduce electron temperatures in a 2-3 month old active region from 1996 September and October, using soft Xray S XV spectra from the Bragg Crystal Spectrometer (BCS) and images from the Soft X-ray Telescope (SXT), both on board the Yohkoh satellite. Our observations cover a full transit of the region, from before its appearance around the east limb until after it disappeared around the west limb. Over most of this transit the region is diffuse and extremely quiescent, with few strong X-ray intensity enhancements (microflares) seen in plots of the GOES flux. During the passage the region's temperature is roughly constant at 2.5+/-0.2 MK in S XV and at 1.9+/-0.1 MK from SXT, with emission measures of about 10(48) cm(-3) for both instruments. Temperatures obtained from SXT are consistently lower then the S XV values, indicating a multithermal plasma. A high-temperature (greater than or similar to 5 MK) component, seen in younger active regions, is virtually absent in this mature active region. Our findings, combined with earlier work, provide a method for estimating S XV temperatures of structures based on their intensity in SXT, even when these structures are not isolated on the Sun and hence not directly resolvable with the full-Sun BCS instrument. Our work also suggests that old active regions form a fundamental component of the quiet-Sun corona during periods of high solar activity. C1 Computat Phys Inc, Fairfax, VA 22031 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Sterling, AC (reprint author), Inst Space & Astronaut Sci, Yoshinodai 3-1-1, Kanagawa 2290022, Japan. EM asterling@solar.stanford.edu NR 43 TC 4 Z9 4 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 JUN PY 1999 VL 346 IS 3 BP 995 EP 1002 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 212FT UT WOS:000081207200040 ER PT J AU Dermer, CD AF Dermer, CD TI Variability in blazars SO ASTROPARTICLE PHYSICS LA English DT Article DE synchrotron emission; radio jets; X-rays and gamma-rays; spectra ID ACTIVE GALACTIC NUCLEI; LACERTAE OBJECT MARKARIAN-421; GAMMA-RAY VARIABILITY; SYNCHROTRON EMISSION; ACCELERATION; STATISTICS; BURSTS; WAVES; FLARE; MODEL AB The kinetic energy of bulk relativistic plasma ejected from the central engine of blazars is converted into nonthermal particle energy in the comoving frame through a process of sweeping up material from the surrounding medium. The resulting deceleration of the bulk plasma introduces a number of effects which must be included in blazar modeling. For example, the varying Doppler factor means that model fits must employ time integrations appropriate to the observing times of the detectors. We find that the ratio of the peak synchrotron fluxes reached at two different photon energies is largest when viewing along the jet axis, and becomes smaller at large angles to the jet axis. This effect is important in studies of the statistics of jet sources. Variability due either to bulk plasma deceleration or radiative cooling must be distinguished in order to apply recently proposed tests for beaming from correlated X-ray and TeV observations. The blast-wave physics developed to analyze these problems implies that most of the energy injected in the comoving frame is originally in the form of nonthermal hadrons. Because plasmoid deceleration can produce rapid variability due to a changing Doppler factor, arguments against hadronic blazar models related to the long radiative cooling time scale of hadrons are not compelling. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Dermer, CD (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Code 7653, Washington, DC 20375 USA. NR 31 TC 12 Z9 12 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-6505 J9 ASTROPART PHYS JI Astropart Phys. PD JUN PY 1999 VL 11 IS 1-2 BP 1 EP 9 DI 10.1016/S0927-6505(99)00017-1 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 212PW UT WOS:000081226300002 ER PT J AU Bottcher, M Dermer, CD AF Bottcher, M Dermer, CD TI Prompt and delayed high-energy emission from cosmological gamma-ray bursts SO ASTROPARTICLE PHYSICS LA English DT Article ID COSMIC-RAYS; ACCELERATION AB In the cosmological blast-wave model for gamma ray bursts (GRBs), high energy (greater than or similar to 10 GeV) gamma-rays are produced either through Compton scattering of soft photons by ultrarelativistic electrons, or as a consequence of the acceleration of protons to ultrahigh energies. We describe the spectral and temporal characteristics of high energy gamma-rays produced by both mechanisms, and discuss how these processes can be distinguished through observations with low-threshold Cerenkov telescopes or GLAST. We propose that Compton scattering of starlight photons by blast wave electrons can produce delayed hares of GeV-TeV radiation. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Rice Univ, Dept Space Phys & Astron, Houston, TX 77005 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Bottcher, M (reprint author), Rice Univ, Dept Space Phys & Astron, MS 108,6100 S Main St, Houston, TX 77005 USA. NR 12 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-6505 J9 ASTROPART PHYS JI Astropart Phys. PD JUN PY 1999 VL 11 IS 1-2 BP 113 EP 115 DI 10.1016/S0927-6505(99)00034-1 PG 3 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 212PW UT WOS:000081226300019 ER PT J AU McCollough, ML Robinson, CR Zhang, SN Harmon, BA Hjellming, RM Waltman, EB Foster, RS Ghigo, FD Briggs, MS Pendleton, GN Johnston, KJ AF McCollough, ML Robinson, CR Zhang, SN Harmon, BA Hjellming, RM Waltman, EB Foster, RS Ghigo, FD Briggs, MS Pendleton, GN Johnston, KJ TI Discovery of correlated behavior between the hard X-ray and the radio bands in Cygnus X-3 SO ASTROPHYSICAL JOURNAL LA English DT Article DE radio continuum : stars; stars : individual (Cygnus X-3); X-rays : stars ID VLBI OBSERVATIONS; GRO J1655-40; SPACED DATA; 8.3 GHZ; OUTBURST; EMISSION; JET AB Using Compton Gamma Ray Observatory BATSE hard X-ray (HXR) data and GHz radio monitoring data from the Green Bank Interferometer, we have performed a long-term study (similar to 1800 days) of the unusual X-ray binary Cyg X-3, resulting in the discovery of a remarkable relationship between these two wavelength bands. We find that during quiescent radio states, the radio flux is strongly anticorrelated with the intensity of the HXR emission. The relationship switches to a correlation with the onset of major radio flaring activity. During major radio flaring activity, the HXR drops to a very low intensity during quenching in the radio and recovers during the radio flare. Injection of plasma into the radio jets of Cyg X-3 occurs during changes in the HXR emission and suggests that disk-related and jet-related components are responsible for the high energy emission. C1 Univ Space Res Assoc, Huntsville, AL 35805 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Natl Radio Astron Observ, Socorro, NM 87801 USA. USN, Res Lab, Washington, DC 20375 USA. Natl Radio Astron Observ, Green Bank, WV 24944 USA. Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. USN Observ, Washington, DC 20392 USA. RP McCollough, ML (reprint author), Univ Space Res Assoc, Huntsville, AL 35805 USA. NR 32 TC 50 Z9 50 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUN 1 PY 1999 VL 517 IS 2 BP 951 EP 955 DI 10.1086/307241 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 208VC UT WOS:000081011700034 ER PT J AU Thompson, BJ Gurman, JB Neupert, WM Newmark, JS Delaboudiniere, JP St Cyr, OC Stezelberger, S Dere, KP Howard, RA Michels, DJ AF Thompson, BJ Gurman, JB Neupert, WM Newmark, JS Delaboudiniere, JP St Cyr, OC Stezelberger, S Dere, KP Howard, RA Michels, DJ TI SOHO/EIT observations of the 1997 April 7 coronal transient: Possible evidence of coronal Moreton waves SO ASTROPHYSICAL JOURNAL LA English DT Article DE solar wind; Sun : activity; Sun : corona; Sun : flares ID FLARE AB We report observations obtained with the Extreme ultraviolet Imaging Telescope (EIT) on board SOHO of a large-scale coronal transient propagating across the disk of the Sun at a speed of 250 km s(-1), in apparent association with a flare and coronal mass ejection. The observations consist of a series of images taken in the Fe XII 195 A bandpass at an average cadence of 15 minutes. A visible increase in coronal emission propagates away from the erupting region, traveling across most of the solar disk in less than an hour. As the wave propagates through the ambient corona, its path is not homogeneous, and it is less observable near strong magnetic features such as active regions and magnetic neutral lines. The characteristics of this event appear to be representative of several other "EIT waves," which we identify as strong candidates for the coronal manifestation of Moreton waves. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Space Applicat Corp, Vienna, VA 22180 USA. Inst Astrophys Spatiale, Orsay, France. Computat Phys Inc, Fairfax, VA 22301 USA. USN, Res Lab, Washington, DC 20375 USA. RP Thompson, BJ (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Thompson, Barbara/C-9429-2012 NR 18 TC 240 Z9 246 U1 1 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUN 1 PY 1999 VL 517 IS 2 BP L151 EP L154 DI 10.1086/312030 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 208VF UT WOS:000081012000020 ER PT J AU Kortenkamp, D Schultz, AC AF Kortenkamp, D Schultz, AC TI Integrating robotics research SO AUTONOMOUS ROBOTS LA English DT Editorial Material C1 NASA, Lyndon B Johnson Space Ctr, Metr Inc, TRACLabs, Houston, TX 77058 USA. USN, Res Lab, Navy Ctr Appl Res Artificial Intelligence, Washington, DC 20375 USA. RP Kortenkamp, D (reprint author), NASA, Lyndon B Johnson Space Ctr, Metr Inc, TRACLabs, Mail Code ER2, Houston, TX 77058 USA. NR 0 TC 9 Z9 9 U1 0 U2 3 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0929-5593 J9 AUTON ROBOT JI Auton. Robot. PD JUN PY 1999 VL 6 IS 3 BP 243 EP 245 DI 10.1023/A:1008984727548 PG 3 WC Computer Science, Artificial Intelligence; Robotics SC Computer Science; Robotics GA 204YH UT WOS:000080793200001 ER PT J AU Schultz, AC Adams, W Yamauchi, B AF Schultz, AC Adams, W Yamauchi, B TI Integrating exploration, localization, navigation and planning with a common representation SO AUTONOMOUS ROBOTS LA English DT Article DE mobile robots; localization; planning; navigation; exploration; evidence grids; integration ID AUTONOMOUS MOBILE ROBOT; EVIDENCE GRIDS AB Two major themes of our research include the creation of mobile robot systems that are robust and adaptive in rapidly changing environments, and the view of integration as a basic research issue. Where reasonable, we try to use the same representations to allow different components to work more readily together and to allow better and more natural integration of and communication between these components. In this paper, we describe our most recent work in integrating mobile robot exploration, localization, navigation, and planning through the use of a common representation, evidence grids. C1 USN, Res Lab, Navy Ctr Appl Res Artificial Intelligence, Washington, DC 20375 USA. RP USN, Res Lab, Navy Ctr Appl Res Artificial Intelligence, Washington, DC 20375 USA. EM schultz@aic.nrl.navy.mil NR 23 TC 30 Z9 30 U1 0 U2 2 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0929-5593 EI 1573-7527 J9 AUTON ROBOT JI Auton. Robot. PD JUN PY 1999 VL 6 IS 3 BP 293 EP 308 DI 10.1023/A:1008936413435 PG 16 WC Computer Science, Artificial Intelligence; Robotics SC Computer Science; Robotics GA 204YH UT WOS:000080793200005 ER PT J AU Yasuhara, TT Dodge, RE Jennings, RT Valdez, MR AF Yasuhara, TT Dodge, RE Jennings, RT Valdez, MR TI Specialty competencies for residents in aerospace medicine SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article DE aerospace medicine education; clinical competence standards; competency-based education; preventive medicine education; internship and residency standards ID PREVENTIVE MEDICINE AB Background: The American College of Preventive Medicine (ACPM), with sponsorship from the Health Resources Administration (HRSA), has published core competencies that are common to all preventive medicine residencies-aerospace medicine (ASM), occupational medicine (OM), and general preventive medicine/public health (CPM/PH). Further development of specialty area competencies for ASM residents was addressed by a working group comprised of representatives from each of the four ASM residency programs. Methods: Representatives from the U.S. Air Force School of Aerospace Medicine, Wright State University, University of Texas Medical Branch-Galveston, and the Naval Operational Medicine institute convened to develop a set of broad competency statements for ASM residents that would encompass the breadth of ASM residency training as it is currently provided in the U.S. Results: A listing of six ASM resident competencies, with supporting skill sets, are presented. In combination with the ACPM core competencies, the ASM resident competencies represent a refocusing of educational objectives on skills attainment. Conclusions: The ASM resident competencies identify the capabilities of graduating ASM residents as distinct from OM and CPM/PH residents. Ar the same time, they are broad enough to permit specific areas of emphasis (e.g., military, civil, or space) to be pursued within the various ASM residencies. This represents the First successful attempt to draft a consolidated statement of educational objectives that has universal acceptance and applicability across ail U.S. aerospace medicine residencies. C1 USAF, Sch Aerosp Med, Dept Aerosp Med, Brooks AFB, TX 78235 USA. Wright State Univ, Dept Community Med, Dayton, OH 45435 USA. Univ Texas, Med Branch, Aerosp Med Residency, Galveston, TX 77550 USA. USN, Operat Med Inst, Aerosp Med Residency, Pensacola, FL USA. RP Yasuhara, TT (reprint author), USAF, Sch Aerosp Med, Dept Aerosp Med, Brooks AFB, TX 78235 USA. NR 5 TC 3 Z9 3 U1 0 U2 0 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD JUN PY 1999 VL 70 IS 6 BP 609 EP 611 PG 3 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 201GB UT WOS:000080585700013 PM 10373055 ER PT J AU Feldstein, MJ Golden, JP Rowe, CA MacCraith, BD Ligler, FS AF Feldstein, Mark J. Golden, Joel P. Rowe, Chris A. MacCraith, Brian D. Ligler, Frances S. TI Array Biosensor: Optical and Fluidics Systems SO BIOMEDICAL MICRODEVICES LA English DT Article DE array biosensor; automation; CCD imaging; fluorescence imaging; antibody patterning; waveguide AB Optical and fluidics systems have been developed as central components for an automated array biosensor. Disposable planar waveguides are patterned with immobilized capture antibodies using a physically isolated patterning (PIP) method. The PIP method enables simultaneous deposition of several antibodies and completely circumvents cross-immobilization problems encountered with other array deposition processes. A multichannel fluidics cell allows numerous assays to be performed on the patterned waveguide. The sensing arrays are optically interrogated using a diode laser with a tailored output to optimize coupling to and maximize excitation uniformity within the waveguide. A patterned cladding is employed to optically isolate the waveguide from perturbations induced by the permanently attached flow cells. Compact optics image the evanescently excited fluorescence onto a large area, cooled CCD array. The image data is processed and automated signal analysis corrects for local background and noise variations. C1 [Feldstein, Mark J.; Golden, Joel P.; Rowe, Chris A.; Ligler, Frances S.] Naval Res Lab, Ctr Bio Mol Sci & Engn, Washington, DC 20375 USA. [MacCraith, Brian D.] Dublin City Univ, Dept Phys, Dublin 9, Ireland. RP Ligler, FS (reprint author), Naval Res Lab, Ctr Bio Mol Sci & Engn, 4555 Overlook Ave SW, Washington, DC 20375 USA. EM fsl@cbmse.nrl.navy.mil FU Office of Naval Research and the Department of Defense FX This work was supported by the Office of Naval Research and the Department of Defense. Dr. Mark Feldstein is a National Research Council Postdoctoral Fellow. The views expressed here are those of the authors and do not reflect opinion or policy of the U.S. Navy or Department of Defense. NR 27 TC 15 Z9 16 U1 0 U2 4 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 1387-2176 EI 1572-8781 J9 BIOMED MICRODEVICES JI Biomed. Microdevices PD JUN PY 1999 VL 1 IS 2 BP 139 EP 153 DI 10.1023/A:1009900608757 PG 15 WC Engineering, Biomedical; Nanoscience & Nanotechnology SC Engineering; Science & Technology - Other Topics GA V33LD UT WOS:000209019400007 PM 16281114 ER PT J AU Bhattacharyya, J Gross, S Lees, J Hastings, M AF Bhattacharyya, J Gross, S Lees, J Hastings, M TI Recent earthquake sequences at Coso: Evidence for conjugate faulting and stress loading near a geothermal field SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Article ID SOUTHERN-CALIFORNIA; FOCAL MECHANISMS; LOMA-PRIETA; LANDERS; AFTERSHOCKS; SEISMICITY; STATE; DECAY AB Two recent earthquake sequences near the Coso geothermal field show clear evidence of faulting along conjugate planes, We present results from analyzing an earthquake sequence occurring in 1998 and compare it with a similar sequence that occurred in 1996. The two sequences followed mainshocks that occurred on 27 November 1996 and 6 March 1998. Both mainshocks ruptured approximately colocated regions of the same fault system, Following a comparison with the background seismicity of the Coso region, we have detected evidence of stress loading within the geothermal field that appears to be in response to the 1998 earthquakes. The M-L = 5.2 mainshock in the 1998 sequence occurred at 5:47 a.m. UTC and was located approximately 45 km north of the town of Ridgecrest in the Coso range. The mainshock of the 1996 sequence had an M-L magnitude of 5.3, There have been no observable surface ruptures associated with either of these sequences. Though the mainshocks for both sequences were located about 900 m apart and have nearly the same local magnitudes, the sequences differ in both their temporal and spatial characteristics. An analysis of the fault-plane solutions of the mainshocks and the aftershock locations suggests that the two sequences ruptured fault planes that are perpendicular to one another. We observe a much faster temporal decay of the 1998 sequence compared to the one in 1996; moreover, while the 1996 sequence was not followed by any sizeable (i.e., M-L > 4.0) aftershocks, the 1998 sequence had four such events. From an estimate of the tectonic stressing rate on the fault that produced the 1998 sequence, we infer a repeat cycle of 135 years for an earthquake of comparable magnitude at Coso. C1 Yale Univ, Dept Geol & Geophys, New Haven, CT 06511 USA. Univ Colorado, CIRES, Boulder, CO 80309 USA. NAWS, Naval Geothermal Program, China Lake, CA USA. RP Bhattacharyya, J (reprint author), Yale Univ, Dept Geol & Geophys, 210 Whitney Ave, New Haven, CT 06511 USA. NR 41 TC 6 Z9 6 U1 0 U2 1 PU SEISMOLOGICAL SOC AMER PI EL CERRITO PA PLAZA PROFESSIONAL BLDG, SUITE 201, EL CERRITO, CA 94530 USA SN 0037-1106 J9 B SEISMOL SOC AM JI Bull. Seismol. Soc. Amer. PD JUN PY 1999 VL 89 IS 3 BP 785 EP 795 PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 208WV UT WOS:000081015600017 ER PT J AU Carroll, TL Pecora, LM AF Carroll, TL Pecora, LM TI Using multiple attractor chaotic systems for communication SO CHAOS LA English DT Article ID SYNCHRONIZATION; SIGNALS; CIRCUITS AB In recent work with symmetric chaotic systems, we synchronized two such systems with one-way driving. The drive system had two possible attractors, but the response system always synchronized with the drive system. In this work, we show how we may combine two attractor chaotic systems with a multiplexing technique first developed by Tsimring and Suschick to make a simple communications system. We note that our response system is never synchronized to our drive system (not even in a generalized sense), but we are still able to transmit information. We characterize the performance of the communications system when noise is added to the transmitted signal. [S1054-1500(99)00602-3]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Carroll, TL (reprint author), USN, Res Lab, Code 6343, Washington, DC 20375 USA. OI Carroll, Thomas/0000-0002-2371-2049 NR 24 TC 29 Z9 31 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1054-1500 J9 CHAOS JI Chaos PD JUN PY 1999 VL 9 IS 2 BP 445 EP 451 DI 10.1063/1.166425 PG 7 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA 200CA UT WOS:000080520500020 ER PT J AU Toniolo, C Formaggio, F Crisma, M Mazaleyrat, JP Wakselman, M George, C Deschamps, JR Flippen-Anderson, JL Pispisa, B Venanzi, M Palleschi, A AF Toniolo, C Formaggio, F Crisma, M Mazaleyrat, JP Wakselman, M George, C Deschamps, JR Flippen-Anderson, JL Pispisa, B Venanzi, M Palleschi, A TI First peptide-based system of rigid donor-rigid interchromophore spacer-rigid acceptor: A structural and photophysical study SO CHEMISTRY-A EUROPEAN JOURNAL LA English DT Review DE conformation analysis; fluorescence spectroscopy; molecular modeling; peptides; structure elucidation ID ALPHA-AMINOISOBUTYRIC-ACID; INTRAMOLECULAR ELECTRON-TRANSFER; HYDROGEN-BOND DISTANCES; EXCITED SINGLET-STATES; ENERGY-TRANSFER; AMINO-ACIDS; CONFORMATIONAL PREFERENCES; OLIGOPEPTIDES RICH; NITROXYL RADICALS; HELICAL PEPTIDE AB The results of X-ray diffraction analysis, fluorescence experiments and molecular mechanics calculations on the terminally protected hexapeptide -(S)Bin-Ala-Aib-TOAC-(Ala)(2)- are presented. This is the first peptide investigated photophysically that is characterized by a) a rigid, binaphthyl-based alpha-amino acid (Bin) fluorophore, b) a rigid interchromophore bridge, the -Ala-Aib-sequence, and c) a rigid, nitroxide-based alpha-amino acid quencher (TOAC). In the crystal state the backbone of the spectroscopically critical 1-4 segment of both independent molecules in the asymmetric unit of the hexapeptide is folded in a regular, left-handed 3(10)-helix. The steady-state fluorescence spectra show a remarkable quenching of Bin emission by the TOAC residue located one complete turn of the helix apart. Time-resolved fluorescence measurements exhibit a biexponential decay with solvent-dependent lifetime components ranging from 0.5 to 1.5 ns and from 3 to 5 ns. Time-decay data combined with molecular mechanics calculations allowed us to assign these lifetimes Co two left-handed 3(10)-helical conformers in which an intramolecular electronic energy transfer from excited Bin to TOAC takes place. For a given solvent the difference between the two lifetimes primarily depends on a different relative orientation of the two chromophores in the conformers, which is in turn related to a different puckering of the TOAC cyclic system. C1 Univ Padua, Dept Organ Chem, I-35131 Padua, Italy. Univ Versailles, SIRCOB, F-78000 Versailles, France. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. Univ Roma Tor Vergata, Dept Chem Sci & Technol, I-00133 Rome, Italy. Univ Rome La Sapienza, Dept Chem, I-00185 Rome, Italy. RP Toniolo, C (reprint author), Univ Padua, Dept Organ Chem, Via Marzolo 1, I-35131 Padua, Italy. RI palleschi, antonio/G-5464-2012; Crisma, Marco/K-6626-2013; OI Crisma, Marco/0000-0003-3552-4106; Deschamps, Jeffrey/0000-0001-5845-0010; TONIOLO, CLAUDIO/0000-0002-2327-1423 NR 108 TC 31 Z9 31 U1 1 U2 15 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0947-6539 J9 CHEM-EUR J JI Chem.-Eur. J. PD JUN PY 1999 VL 5 IS 8 BP 2254 EP 2264 DI 10.1002/(SICI)1521-3765(19990802)5:8<2254::AID-CHEM2254>3.0.CO;2-1 PG 11 WC Chemistry, Multidisciplinary SC Chemistry GA 223XD UT WOS:000081866100005 ER PT J AU Rascona, DA Gumpert, BC AF Rascona, DA Gumpert, BC TI Pulmonary embolism - Treatment vs nontreatment SO CHEST LA English DT Letter C1 USN, Med Ctr, Portsmouth, VA 23708 USA. RP Rascona, DA (reprint author), USN, Med Ctr, 620 John Paul Jones Circle, Portsmouth, VA 23708 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER COLL CHEST PHYSICIANS PI NORTHBROOK PA 3300 DUNDEE ROAD, NORTHBROOK, IL 60062-2348 USA SN 0012-3692 J9 CHEST JI Chest PD JUN PY 1999 VL 115 IS 6 BP 1755 EP 1755 PG 1 WC Critical Care Medicine; Respiratory System SC General & Internal Medicine; Respiratory System GA 206FX UT WOS:000080867600054 PM 10378585 ER PT J AU L'Esperance, D Williams, BA Fleming, JW AF L'Esperance, D Williams, BA Fleming, JW TI Intermediate species profiles in low pressure premixed flames inhibited by fluoromethanes SO COMBUSTION AND FLAME LA English DT Article ID LASER-INDUCED FLUORESCENCE; ATOM-RADICAL KINETICS; METHANE-AIR FLAMES; HYDROGEN; NO2; CF; NITROGEN; N2O AB We have investigated premixed 10 torr methane/oxygen flames containing CH3F, CH2F2, CHF3, and CF4. Profiles of temperature and CH* chemi-luminescence were acquired, and laser-induced fluorescence (LIF) was used to obtain profiles of the intermediate species H, OH, CH, CF, CHF, CF2, and CF2O. The fluoromethanes were added in amounts such that each flame had the same flux of fluorine atoms. In the flames containing CH3F, CH2F2, and CHF3, the methane flow was adjusted to give an equivalence ratio of 1.07 for all three inhibited flames. The experimental intermediate profiles were compared to predicted profiles calculated from a hydrofluorocarbon kinetic mechanism recently developed at NIST. No fluorinated intermediates were detectable in the CF4 inhibited flame, indicating that this agent does not react significantly under the flame conditions studied. The temperature profiles, H atom profiles, and OH profiles for the other three fluoromethane inhibited flames are nearly identical, indicating that flames containing different fluorocarbon compounds, but identical proportions of fluorine atoms, have similar structures. The kinetic model correctly predicts the location of the reaction zone in the flames containing CH2F2 and CH3F. In the CHF3 flame, however, the location of the reaction zone is predicted to be too far above the burner surface, and concentrations of H and OH are too low. The discrepancy appears to be due to pressure dependence and third body efficiencies of the agent thermal decomposition. Furthermore, relative amounts of CF, CH, CF2, and CHF in the different flames are not very well predicted. In general, partially fluorinated methyl and methylene radicals appear to have a greater than predicted propensity to lose hydrogen atoms rather than fluorine. We propose modifications to the fluorine mechanism to correct the discrepancies observed in the low pressure experiments, while simultaneously achieving good agreement with atmospheric pressure flame speed data in CH4/air/CHF, flames, and, except in rich conditions (phi > 1.25) CH4/air/CH2F2 flames. (C) 1999 by The Combustion Institute. C1 USN, Res Lab, Navy Technol Ctr Safety & Survivabil, Combust Dynam Sect, Washington, DC 20375 USA. RP Williams, BA (reprint author), USN, Res Lab, Navy Technol Ctr Safety & Survivabil, Combust Dynam Sect, Code 6185, Washington, DC 20375 USA. NR 56 TC 22 Z9 22 U1 0 U2 5 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD JUN PY 1999 VL 117 IS 4 BP 709 EP 731 DI 10.1016/S0010-2180(98)00126-6 PG 23 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 177RL UT WOS:000079224800003 ER PT J AU Mikolajczak, B Rumbut, JT AF Mikolajczak, B Rumbut, JT TI Distributed dynamic programming using concurrent object-orientedness with Actors visualised by high-level Petri nets SO COMPUTERS & MATHEMATICS WITH APPLICATIONS LA English DT Article DE distributed dynamic programming; distributed artificial intelligence; concurrent object-orientedness; Actors; high-level Petri nets; visualization AB This paper deals with application of concurrent object-oriented programming with Actors to solve dynamic programming problems in a distributed computing environment. This area of research is often called distributed artificial intelligence. Using a dynamic programming example of chained matrix multiplication, a method of managing dynamic programming searches in a distributed programming environment with Actors is presented. Distributed computations with Actors are visualized by means of Time-Varying Automata (for cases with no intra-actor concurrency) or using a class of high-level nets called Hierarchical Colored Petri Nets (for cases with intra-actor concurrency). Design and implementation features of the specific Actor-based programming environment, using a concurrent extension of C++, are also discussed. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ Massachusetts Dartmouth, Dept Informat & Comp Sci, N Dartmouth, MA 02747 USA. Naval Undersea Warfare Ctr, Architecture & Comp Syst Div, Newport, RI 02841 USA. RP Mikolajczak, B (reprint author), Univ Massachusetts Dartmouth, Dept Informat & Comp Sci, N Dartmouth, MA 02747 USA. NR 14 TC 1 Z9 2 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0898-1221 J9 COMPUT MATH APPL JI Comput. Math. Appl. PD JUN PY 1999 VL 37 IS 11-12 BP 23 EP 34 DI 10.1016/S0898-1221(99)00139-X PG 12 WC Mathematics, Applied SC Mathematics GA 202JB UT WOS:000080647600006 ER PT J AU McDaniel, DH Lord, J Ash, K Newman, J Zukowski, M AF McDaniel, DH Lord, J Ash, K Newman, J Zukowski, M TI Laser hair removal - A review and report on the use of the long-pulsed alexandrite laser for hair reduction of the upper lip, leg, back, and bikini region SO DERMATOLOGIC SURGERY LA English DT Article; Proceedings Paper CT 18th Annual Meeting of the American-Society-for-Laser-Medicine-and-Surgery CY APR 06, 1998 CL SAN DIEGO, CALIFORNIA SP Amer Soc Laser Med & Surg ID MODE RUBY-LASER; SELECTIVE PHOTOTHERMOLYSIS; HIRSUTISM; ELECTROLYSIS; FOLLICLES; DAMAGE AB BACKGROUND. The mechanism and permanence of laser-assisted hair removal remains a formidable task in the medical community. OBJECTIVE. The purpose of this study was to determine the safety and long-term efficacy of the long-pulsed or normal mode alexandrite infrared laser for hair depilation. METHODS. Beginning in October 1996, a total of 31 anatomic sites on 22 patients ranging in age from 25 to 59 years (mean 42 years) were evaluated to assess hair removal. Treatment sites included 17 upper lips, 9 legs, 2 backs, and 3 bikini regions. Eligible patients were of Fitzpatrick skin types I-m. Patients were treated using the long-pulsed alexandrite infrared laser at 755 nm, single-pulse technique, 10 mm spot size, 10% overlap, pulse durations of 5, 10, and 20 msec, and a fluence of 20 J/cm(2). Subjective patient improvement and objective, blinded graded improvement was assessed at 1, 2, 3, and 6 months. RESULTS. Objective blinded grading at 6 months revealed that hair reduction varied both with the pulse duration and anatomic location. Maximum reductions observed were 40%, 56%, 50%, and 15% for the lip, leg, back, and bikini areas, respectively. Upper lip hair reduction increased from 40% to 54% at 6 months when a second treatment was performed 8 weeks after the initial treatment. CONCLUSION. The long-pulsed alexandrite laser is safe and effective in reducing hair growth. Treatment efficacy varies with the anatomic location, pulse duration, and number of treatments. A single-pulse technique utilizing a 10 msec pulse duration at 20 J/cm(2) produced the greatest hair reduction. No permanent adverse effects occurred on skin types I-III at the parameters tested. C1 Laser Ctr Virginia, Virginia Beach, VA USA. Eastern Virginia Med Sch, Norfolk, VA 23501 USA. USN, Med Ctr, Dept Gen Surg, Portsmouth, VA USA. Zukowski Ctr Cosmet Plast Surg, Wilmette, IL 60098 USA. RP McDaniel, DH (reprint author), Laser Ctr Virginia, 933 1st Colonial Rd,Suite 113, Virginia Beach, VA USA. NR 44 TC 33 Z9 34 U1 0 U2 2 PU BLACKWELL SCIENCE INC PI MALDEN PA 350 MAIN ST, MALDEN, MA 02148 USA SN 1076-0512 J9 DERMATOL SURG JI Dermatol. Surg. PD JUN PY 1999 VL 25 IS 6 BP 425 EP 430 DI 10.1046/j.1524-4725.1999.08118.x PG 6 WC Dermatology; Surgery SC Dermatology; Surgery GA 204XL UT WOS:000080790600001 PM 10469087 ER PT J AU Steeds, JW Gilmore, A Bussmann, KM Butler, JE Koidl, P AF Steeds, JW Gilmore, A Bussmann, KM Butler, JE Koidl, P TI On the nature of grain boundary defects in high quality CVD diamond films and their influence on physical properties SO DIAMOND AND RELATED MATERIALS LA English DT Article DE transmission electron microscopy; CVD diamond; defects; thermal conductivity; field emission ID VAPOR-DEPOSITED DIAMOND; THERMAL-CONDUCTIVITY; SCATTERING AB Transmission electron microscopy samples have been prepared from high quality, thick (>100 mu m) CVD diamond films in order to undertake a detailed study of the regions adjacent to the columnar grain boundaries. Using both weak beam and strong matrix diffracted beams and also twin reflections in carefully chosen crystal orientations, it has been possible to show that the boundaries that appear defect-free at first sight are in fact associated with considerable defect densities of characteristic types. These defects have been analysed and the results are presented. An attempt is made to correlate these observations with the anisotropy and temperature dependence of the thermal conductivity of the films and also with their field-emission properties. (C) 1999 Elsevier Science S.A. All rights reserved. C1 Univ Bristol, Dept Phys, Bristol BS8 1TL, Avon, England. USN, Res Labs, Washington, DC 20375 USA. Fraunhofer Inst Angew Festkorperphys, D-79108 Freiburg, Germany. RP Steeds, JW (reprint author), Univ Bristol, Dept Phys, Bristol BS8 1TL, Avon, England. RI Butler, James/B-7965-2008 OI Butler, James/0000-0002-4794-7176 NR 16 TC 25 Z9 26 U1 0 U2 7 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-9635 J9 DIAM RELAT MATER JI Diam. Relat. Mat. PD JUN PY 1999 VL 8 IS 6 BP 996 EP 1005 DI 10.1016/S0925-9635(98)00425-7 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA 205JM UT WOS:000080817600002 ER PT J AU Volino, RJ Smith, GB AF Volino, RJ Smith, GB TI Use of simultaneous IR temperature measurements and DPIV to investigate thermal plumes in a thick layer cooled from above SO EXPERIMENTS IN FLUIDS LA English DT Article ID CONVECTION; VELOCIMETRY AB Simultaneous measurements of surface temperature and the underlying velocity field are presented for a thick horizontal layer evaporatively cooled from above. Previous studies have focused on either the temperature field at the cooled surface or, in a small number of cases, on point velocity measurements in the flow. The current investigation is, to the knowledge of the authors, the first to simultaneously and non-intrusively document both the surface temperature and underlying velocity field in this type of flow. An infrared (IR) sensing array was used to capture the instantaneous free surface temperature field while two-dimensional velocity measurements in planes either perpendicular or parallel to the free surface were acquired using digital particle image velocimetry (DPIV). Data from two cases are discussed. C1 USN, Res Lab, Washington, DC 20375 USA. USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. RP Smith, GB (reprint author), USN, Res Lab, Code 7253,4555 Overlook Ave SW, Washington, DC 20375 USA. RI Volino, Ralph/G-9293-2011 NR 15 TC 38 Z9 38 U1 0 U2 2 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0723-4864 J9 EXP FLUIDS JI Exp. Fluids PD JUN PY 1999 VL 27 IS 1 BP 70 EP 78 DI 10.1007/s003480050330 PG 9 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 207DD UT WOS:000080919400009 ER PT J AU Gao, X Dodds, RH Tregoning, RL Joyce, JA Link, RE AF Gao, X Dodds, RH Tregoning, RL Joyce, JA Link, RE TI A Weibull stress model to predict cleavage fracture in plates containing surface cracks SO FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES LA English DT Article DE cleavage fracture; Weibull stress; failure probability; master curve; surface crack ID BRITTLE-FRACTURE; LOCAL APPROACH; TRANSITION AB This study applies recent advances in probabilistic modelling of cleavage fracture to predict the measured fracture behaviour of surface crack plates fabricated from an A515-70 pressure vessel steel. Modifications of the conventional, two-parameter Weibull stress model introduce a non-zero, threshold parameter (sigma(w-min)). The introduction of sigma(w-min) brings numerical predictions of scatter in toughness data into better agreement with experimental measurements, and calibration of this new parameter requires no additional experimental data. The Weibull modulus (m) and scaling parameter (sigma(u)) are calibrated using a new strategy based on the toughness transferability model, which eliminates the non-uniqueness that arises in calibrations using only small-scale yielding toughness data. Here, the Weibull stress model is calibrated using toughness data from deep-notch C(T) and shallow-notch SE(B) specimens, and is then applied to predict the measured response of surface crack plates loaded in different combinations of tension and bending. The model predictions accurately capture the measured distributions of fracture toughness values. C1 Univ Illinois, Dept Civil Engn, Urbana, IL 61801 USA. USN, Ctr Surface Warfare, Fatigue & Fracture Branch, Bethesda, MD 20817 USA. USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. RP Dodds, RH (reprint author), Univ Illinois, Dept Civil Engn, Urbana, IL 61801 USA. NR 27 TC 60 Z9 62 U1 0 U2 8 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 8756-758X EI 1460-2695 J9 FATIGUE FRACT ENG M JI Fatigue Fract. Eng. Mater. Struct. PD JUN PY 1999 VL 22 IS 6 BP 481 EP 493 PG 13 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 217BQ UT WOS:000081479900003 ER PT J AU Djuth, FT Bernhardt, PA Tepley, CA Gardner, JA Kelley, MC Broadfoot, AL Kagan, LM Sulzer, MP Elder, JH Selcher, C Isham, B Brown, C Carlson, HC AF Djuth, FT Bernhardt, PA Tepley, CA Gardner, JA Kelley, MC Broadfoot, AL Kagan, LM Sulzer, MP Elder, JH Selcher, C Isham, B Brown, C Carlson, HC TI Large airglow enhancements produced via wave-plasma interactions in sporadic E SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID POWER RADIO-WAVES; ARTIFICIAL AIRGLOW; REGION AB In the past there has been great interest in monitoring enhanced 557.7 nm O(S-1) emissions from the thermosphere in connection with high-power, high-frequency (HF) radio wave modification of the F region ionosphere. These emissions are considered to be evidence that the HF-modified electron distribution function is non-Maxwellian because a significant flux of similar to 5-6 eV electrons is required to produce the airglow. The suprathermal tail is believed to develop as a result of nonlinear plasma processes. Past F region observations of 557.7 nm airglow at Arecibo Observatory, Puerto Rico have yielded only a few Rayleighs of enhanced emissions. Recently, airglow enhancements were monitored in sporadic E above Arecibo. Surprisingly, these experiments yielded similar to 55 Rayleighs of enhanced 557.7 nm airglow and the first observations of emissions from the N-2 first positive molecular bands. The observations imply that a large flux of energetic (5-10 eV) electrons is generated as part of the wave-plasma interaction in sporadic E. C1 Geospace Res Inc, El Segundo, CA 90245 USA. USN, Res Lab, Washington, DC 20375 USA. Natl Astron & Ionosphere Ctr, Arecibo Observ, Arecibo, PR 00613 USA. USAF, Res Lab, VSBI, Bedford, MA 01731 USA. Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. Brown Comp Co, Res Triangle Pk, NC 27709 USA. USAF, Res Lab, AFOSR, Arlington, VA 22203 USA. RP Djuth, FT (reprint author), Geospace Res Inc, 550 N Continental Blvd, El Segundo, CA 90245 USA. NR 16 TC 35 Z9 35 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JUN 1 PY 1999 VL 26 IS 11 BP 1557 EP 1560 DI 10.1029/1999GL900296 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 202PG UT WOS:000080660900012 ER PT J AU Salas, E Fowlkes, JE Stout, RJ Milanovich, DM Prince, C AF Salas, E Fowlkes, JE Stout, RJ Milanovich, DM Prince, C TI Does CRM training improve teamwork skills in the cockpit?: Two evaluation studies SO HUMAN FACTORS LA English DT Article ID MANAGEMENT ATTITUDES; COORDINATION; PERFORMANCE AB Crew resource management (CRM) has been the most widely used instructional strategy to enhance teamwork skills within aviation. However, few studies have provided empirical evidence that this strategy results in increased Use of teamwork behaviors. The current paper describes 2 evaluation studies of CRM training that were conducted with 96 naval aviators and followed a multiple assessment approach. Results indicated that highly experienced aviators benefited from the training which focused on increasing the use of several critical teamwork skills. These rare evaluation data suggest that CRM training is a viable strategy for improving teamwork in the cockpit. implications for team training are discussed. C1 Univ Cent Florida, Dept Psychol, Orlando, FL 32816 USA. USN, Air Warfare Ctr, Training Syst Div, Orlando, FL USA. RP Salas, E (reprint author), Univ Cent Florida, Dept Psychol, POB 160000, Orlando, FL 32816 USA. NR 33 TC 58 Z9 61 U1 1 U2 10 PU HUMAN FACTORS SOC PI SANTA MONICA PA BOX 1369, SANTA MONICA, CA 90406 USA SN 0018-7208 J9 HUM FACTORS JI Hum. Factors PD JUN PY 1999 VL 41 IS 2 BP 326 EP 343 DI 10.1518/001872099779591169 PG 18 WC Behavioral Sciences; Engineering, Industrial; Ergonomics; Psychology, Applied; Psychology SC Behavioral Sciences; Engineering; Psychology GA 217AU UT WOS:000081477800011 ER PT J AU Bishop, BE Spong, MW AF Bishop, BE Spong, MW TI Vision-based control of an air hockey playing robot. SO IEEE CONTROL SYSTEMS MAGAZINE LA English DT Article ID MANIPULATION C1 USN Acad, Dept Weap & Syst Engn, Annapolis, MD 21402 USA. Univ Illinois, Coordinated Sci Lab, Urbana, IL 61801 USA. RP USN Acad, Dept Weap & Syst Engn, Annapolis, MD 21402 USA. EM bishop@novell.nadn.navy.mil; m-spong@uiuc.edu NR 19 TC 9 Z9 9 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1066-033X EI 1941-000X J9 IEEE CONTR SYST MAG JI IEEE Control Syst. Mag. PD JUN PY 1999 VL 19 IS 3 BP 23 EP 32 DI 10.1109/37.768537 PG 10 WC Automation & Control Systems SC Automation & Control Systems GA 200FL UT WOS:000080528900003 ER PT J AU Snitchler, G Kalsi, SS Manlief, M Schwall, RE Sidi-Yekhlef, A Ige, S Medeiros, R Francavilla, TL Gubser, DU AF Snitchler, G Kalsi, SS Manlief, M Schwall, RE Sidi-Yekhlef, A Ige, S Medeiros, R Francavilla, TL Gubser, DU TI High-field warm-bore HTS conduction cooled magnet SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1998 Applied Superconductivity Conference CY SEP 13-18, 1998 CL PALM DESERT, CALIFORNIA AB A 7.25 T laboratory magnet utilizing Bi 2223 conductor has been designed, built, and installed at the Naval Research Laboratory. Operating at 21 K at full field, the coil provides field homogeneity of +/- 1% in a 2-inch warm-bore. The system is conduction cooled with a pair of Leybold single stage cryocoolers that allow cooldown in less than 36 hours and allow extended fast ramp operation. Operation at a total refrigerator input power of 6 kW is facilitated by the use of ASC Cryosaver(TM) HTS current leads. The fully integrated system consists of the magnet, cryogenic system, control and protection system and power supply. This paper presents information on the magnet design, construction and subsequent testing. C1 Amer Supercond Corp, Westborough, MA 01581 USA. USN, Res Lab, Washington, DC 20375 USA. RP Snitchler, G (reprint author), Amer Supercond Corp, Westborough, MA 01581 USA. NR 11 TC 12 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 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1999 VL 9 IS 2 BP 553 EP 558 DI 10.1109/77.783356 PN 1 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 225LY UT WOS:000081964100109 ER PT J AU Francavilla, TL Khan, HR Browning, VM AF Francavilla, TL Khan, HR Browning, VM TI The magnetic field and temperature dependent transport critical current density of Hg-Pb-Bi-Ca-Cu-O ceramic compounds SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1998 Applied Superconductivity Conference CY SEP 13-18, 1998 CL PALM DESERT, CALIFORNIA ID SUPERCONDUCTIVITY; PRESSURES AB Mercury-based, ceramic superconductors have been prepared by powder metallurgy, utilizing a technique of direct synthesis from the oxide powders, The tetragonal Hg-1223 phase was prepared and stabilized over a range of Pb and BiPb compositions, The most interesting material had an onset superconducting transition temperature of approximately 133 K. Critical current densities were obtained directly from transport measurements and indirectly from magnetization measurements. The transport critical current densities were orders of magnitude smaller than the intra-grain critical current densities. The data suggest that the transport critical current is limited by weak coupling between the grains, and that the intra-grain critical current densities deteriorate rapidly above 20K. C1 USN, Res Lab, Washington, DC 20375 USA. FEM, D-73525 Schwabisch Gemund, Germany. RP Francavilla, TL (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 15 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 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1999 VL 9 IS 2 BP 1771 EP 1774 DI 10.1109/77.784798 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 225MA UT WOS:000081964300088 ER PT J AU Rudman, DA Stork, FJB Booth, JC Juang, JY Vale, LR Beatty, GJ Williams, CI Beall, JA Ono, RH Qadri, SB Osofsky, MS Skelton, EF Claassen, JH Gibson, G MacManus-Driscoll, JL Malde, N Cohen, LF AF Rudman, DA Stork, FJB Booth, JC Juang, JY Vale, LR Beatty, GJ Williams, CI Beall, JA Ono, RH Qadri, SB Osofsky, MS Skelton, EF Claassen, JH Gibson, G MacManus-Driscoll, JL Malde, N Cohen, LF TI Role of oxygen pressure during deposition on the microwave properties of YBCO films SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1998 Applied Superconductivity Conference CY SEP 13-18, 1998 CL PALM DESERT, CALIFORNIA ID THIN-FILMS; SUPERCONDUCTING FILMS; SURFACE-RESISTANCE; TEMPERATURE; INHOMOGENEITIES; YBA2CU3O7-DELTA AB We have studied the effect of oxygen pressure (PO,) during pulsed laser deposition on the properties of YBCO films, with particular attention to the low power microwave surface resistance R-s. Above a threshold oxygen pressure the properties of the films are nearly independent of PO2 during deposition and are typical of high quality YBCO films. The films made below this threshold pressure have increased disorder which produces a reduced T-c and an expanded c-axis lattice parameter. However, these films also have significantly reduced low temperature R-s, which is likely a direct result of the increased scattering in these films. Preliminary Raman measurements show no increase in the Y-Ba cation disorder in these low PO2 films, so that a different disorder mechanism must be present. C1 Natl Inst Stand & Technol, Boulder, CO 80309 USA. USN, Res Lab, Washington, DC 20375 USA. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, Ctr Superconduct, London, England. Natl Chiao Tung Univ, Hsinchu, Taiwan. RP Rudman, DA (reprint author), Natl Inst Stand & Technol, 325 Broadway, Boulder, CO 80309 USA. RI Osofsky, Michael/A-1050-2010 NR 17 TC 10 Z9 10 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1999 VL 9 IS 2 BP 2460 EP 2464 DI 10.1109/77.784975 PN 2 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 225MA UT WOS:000081964300259 ER PT J AU Ozyuzer, L Miyakawa, N Zasadzinski, JF Yusof, Z Romano, P Kendziora, C Guptasarma, P Hinks, DG Gray, KE AF Ozyuzer, L Miyakawa, N Zasadzinski, JF Yusof, Z Romano, P Kendziora, C Guptasarma, P Hinks, DG Gray, KE TI Simultaneous quasiparticle and Josephson tunneling in BSCCO-2212 break junctions SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1998 Applied Superconductivity Conference CY SEP 13-18, 1998 CL PALM DESERT, CALIFORNIA ID T-C SUPERCONDUCTORS; BI2SR2CACU2O8+DELTA; TEMPERATURE; SPECTROSCOPY; GAP; SYMMETRY AB Tunneling measurements are reported for superconductor-insulator-superconductor (SIS) break junctions on underdoped, optimally-doped, and overdoped single crystals of Bi2Sr2CaCu2O8+delta (Bi-2212). The junction I - V characteristics exhibit well-defined quasiparticle current jumps at eV = 2 Delta as well as hysteretic Josephson currents. The quasiparticle branch has been analyzed in the framework of d(x2-y2) (d-wave) superconductivity and indicates that there is preferential tunneling along the lobe directions of the d-wave gap. For overdoped Bi-2212 with T-c=62 K, the Josephson current is measured as a function of junction resistance, R-n, which varied by two orders of magnitude (1 k Omega to 100 k Omega). IcRn product is proportional to the 0.47 power of I-c and displays a maximum of 7.0 mV. When the hole doping is decreased from overdoped (T-c=62 K) to the underdoped regime (T-c=70 K), the average IcRn product increases as does the quasiparticle gap. The maximum IcRn is similar to 40% of the Delta/e at each doping level, with a value as high as 25 mV in underdoped Bi-2212. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Izmir Inst Technol, Dept Phys, Izmir, Turkey. Sci Univ Tokyo, Dept Appl Phys, Tokyo 162, Japan. IIT, Chicago, IL 60616 USA. USN, Res Lab, Washington, DC 20375 USA. RP Ozyuzer, L (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Ozyuzer, Lutfi/H-3142-2011 NR 19 TC 4 Z9 4 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1999 VL 9 IS 2 BP 2898 EP 2901 DI 10.1109/77.783635 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 225MC UT WOS:000081964500015 ER PT J AU Gulian, AM Van Vechten, D Wood, KS Gritz, GG Horwitz, JS Osofsky, MS Pond, JM Qadri, SB Stroud, RM Thrasher, JB Vartanyan, VO Kuzanyan, AS Nikogosyan, VR Gyulamiryan, AL AF Gulian, AM Van Vechten, D Wood, KS Gritz, GG Horwitz, JS Osofsky, MS Pond, JM Qadri, SB Stroud, RM Thrasher, JB Vartanyan, VO Kuzanyan, AS Nikogosyan, VR Gyulamiryan, AL TI Imaging detectors based on the response of anisotropic layered materials SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1998 Applied Superconductivity Conference CY SEP 13-18, 1998 CL PALM DESERT, CALIFORNIA ID LASER-INDUCED VOLTAGES; YBA2CU3O7-DELTA FILMS; ROOM-TEMPERATURE AB The inherent properties of naturally layered materials such as the high-temperature superconductors cause a transient voltage when a light pulse is absorbed. The amplitude is proportional to the absorbed energy. Observable pulses arise in the HTS materials even at roam temperature. A phenomenological model of the effects consistent with our observations on the first generation of sensors will be discussed along with recent results regarding sensitivity to single photons, array geometry and readout, and energy resolution. C1 USN, Res Lab, Univ Space Res Assoc, Washington, DC 20375 USA. Off Naval Res, Arlington, VA 22217 USA. Armenian Acad Sci, Inst Phys Res, Ashtarak 378410, Armenia. RP Gulian, AM (reprint author), USN, Res Lab, Univ Space Res Assoc, Washington, DC 20375 USA. RI Osofsky, Michael/A-1050-2010 NR 15 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 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1999 VL 9 IS 2 BP 3194 EP 3197 DI 10.1109/77.783708 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 225MC UT WOS:000081964500088 ER PT J AU Soulen, RJ Osofsky, MS Nadgorny, B Ambrose, T Broussard, PR Rubinstein, M Byers, J Tanaka, CT Nowack, J Moodera, JS Laprade, G Barry, A Coey, MD Mukovskii, YM Shulyatev, D Arsenov, A AF Soulen, RJ Osofsky, MS Nadgorny, B Ambrose, T Broussard, PR Rubinstein, M Byers, J Tanaka, CT Nowack, J Moodera, JS Laprade, G Barry, A Coey, MD Mukovskii, YM Shulyatev, D Arsenov, A TI Conduction across the interface between a superconductor and a spin polarized metal SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1998 Applied Superconductivity Conference CY SEP 13-18, 1998 CL PALM DESERT, CALIFORNIA AB We have studied Andreev reflection in point contacts formed between several low Tc superconductors and various spin polarized normal metals. We have also developed a theoretical model for the phenomenon. There is good accordance between theory and experiment. C1 USN, Res Lab, Washington, DC 20375 USA. George Washington Univ, Washington, DC 20375 USA. MIT, Francis Bitter Natl Magnet Lab, Cambridge, MA 02139 USA. INSA, Toulouse, France. Univ Dublin Trinity Coll, Dept Phys, Dublin 2, Ireland. MSIS, Moscow, Russia. RP Soulen, RJ (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Osofsky, Michael/A-1050-2010; Shulyatev, Dmitry/M-7278-2014 OI Shulyatev, Dmitry/0000-0002-7642-0277 NR 8 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 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1999 VL 9 IS 2 BP 3636 EP 3639 DI 10.1109/77.783816 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 225MC UT WOS:000081964500196 ER PT J AU Jin, I Chen, Z Wu, T Pai, SP Dong, Z Ogale, SB Ramesh, R Venkatesan, T Johnson, M Finley, E Hegmann, FA Freeman, MR AF Jin, I Chen, Z Wu, T Pai, SP Dong, Z Ogale, SB Ramesh, R Venkatesan, T Johnson, M Finley, E Hegmann, FA Freeman, MR TI Spin-polarized quasiparticle injection into YBCO SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1998 Applied Superconductivity Conference CY SEP 13-18, 1998 CL PALM DESERT, CALIFORNIA ID TUNNEL INJECTION; QUASI-PARTICLES; FILMS; HETEROSTRUCTURES; SUPERCONDUCTOR; FERROMAGNET; SUPPRESSION; DEVICES AB FET-type devices have been fabricated by using trilayers of Nd0.7Sr0.3MnO3 (NSMO) or LaNiO3 (LN) (gate)/LnAlO(3) (LAO) (barrier) / Yba(2)Cu(3)O(7) (YBCO) (channel) in order to investigate effect of quasiparticle injection into YBCO. Here, NSMO and LNO were used as gate electrodes for injection of spin-polarized and spin-unpolarized quasiparticles into the superconducting channel, respectively. When injecting along the c-axis of YBCO, the critical current was suppressed with spin-polarized quasiparticles 30 times more efficiently than,vith spin-unpolarized quasiparticles. Differential current gain, defined as a differential change of the critical current to injection current change, has been achieved up to similar to 16 for c-axis YBCO. If the response time is limited by quasiparticle relaxation time of similar to 10 ps, the device may be useful for fast electronics. Preliminary high-speed measurements Indicate that part of the critical current suppression may be caused by quasiparticle injection, not all by heating. When injecting along a-axis, no significant dependence on quasiparticle polarization was observed. Other superconductors such as Pr1.85Ce0.15CUO4 (PCCO) and PbIn have been tested in similar devices for comparison. C1 Univ Maryland, Ctr Supercond Res, College Pk, MD 20742 USA. Univ Maryland, Dept Phys, College Pk, MD 20742 USA. USN, Res Lab, Washington, DC 20375 USA. Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. Univ Maryland, Dept Elect Engn, College Pk, MD 20742 USA. Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. RP Jin, I (reprint author), Univ Maryland, Ctr Supercond Res, College Pk, MD 20742 USA. RI Wu, Tom/A-1158-2012; Venkatesan, Thirumalai/E-1667-2013; Freeman, Mark/E-4609-2013 OI Wu, Tom/0000-0003-0845-4827; NR 18 TC 2 Z9 2 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1999 VL 9 IS 2 BP 3640 EP 3643 DI 10.1109/77.783817 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 225MC UT WOS:000081964500197 ER PT J AU Xu, H Gao, EZ Sahba, S Miller, JR Ma, QY Pond, JM AF Xu, H Gao, EZ Sahba, S Miller, JR Ma, QY Pond, JM TI Design and implementation of a lumped-element multipole HTS filter at 15 MHz SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1998 Applied Superconductivity Conference CY SEP 13-18, 1998 CL PALM DESERT, CALIFORNIA AB We have designed a three-pole bandpass filter operating at 15 MHz. The parameters of the filter include high Q, narrow band, low insertion loss and a return loss of 20 dB. The filter was fabricated from double-sided YBCO thin film on a two inch LAO substrate. Our design utilizes individual HTS lumped elements (interdigital capacitors and meander line inductors) to of the poles of the filter. The design and modeling of the filter are discussed in detail. Experimental results from the S-parameter measurements will be presented, Good agreement has been found between the simulation results and experimental data. C1 Columbia Univ, New York, NY 10027 USA. USA, HQ CECOM, Ft Monmouth, NJ 07703 USA. USN, Res Lab, Microwave Technol Branch, Washington, DC 20375 USA. RP Xu, H (reprint author), Columbia Univ, New York, NY 10027 USA. NR 12 TC 4 Z9 4 U1 1 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1999 VL 9 IS 2 BP 3886 EP 3888 DI 10.1109/77.783876 PN 3 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 225MC UT WOS:000081964500256 ER PT J AU Luine, J Abelson, L Brundrett, D Burch, J Dantsker, E Hummer, K Kerber, G Wire, M Yokoyama, K Bowling, D Neel, M Hubbell, S Li, K AF Luine, J Abelson, L Brundrett, D Burch, J Dantsker, E Hummer, K Kerber, G Wire, M Yokoyama, K Bowling, D Neel, M Hubbell, S Li, K TI Application of a DC SQUID array amplifier to an electrically small active antenna SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1998 Applied Superconductivity Conference CY SEP 13-18, 1998 CL PALM DESERT, CALIFORNIA ID SUPERCONDUCTORS AB We have built and operated a wide band electrically small active antenna consisting of a YBa(2)Cu(3)O7 half-loop over ground plane antenna, an LTS (niobium) 200 element DC SQUID array amplifier, and low-noise cryogenic GaAs buffer amplifier. These components were integrated with a liquid He flow cryostat into a portable stand-alone package. Measurements of active antenna response from 50 to 500 MHz were made using a transverse electromagnetic cell to illuminate the half-loop antenna. At frequencies below the observed antenna resonance (250 MHz) the active antenna response is flat thereby exhibiting wide band gain. C1 TRW Co Inc, Space & Elect Grp, Redondo Beach, CA 90278 USA. USN, Air Warfare Ctr, Weapons Div, China Lake, CA USA. Boeing Co, Seattle, WA 98124 USA. RP Luine, J (reprint author), TRW Co Inc, Space & Elect Grp, 1 Space Pk, Redondo Beach, CA 90278 USA. NR 5 TC 21 Z9 21 U1 1 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1999 VL 9 IS 2 BP 4141 EP 4144 DI 10.1109/77.783937 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 225MC UT WOS:000081964500317 ER PT J AU Booth, JC Beall, JA Rudman, DA Vale, LR Ono, RH Holloway, CL Qadri, SB Osofsky, MS Skelton, EF Claassen, JH Gibson, G MacManus-Driscoll, JL Malde, N Cohen, LF AF Booth, JC Beall, JA Rudman, DA Vale, LR Ono, RH Holloway, CL Qadri, SB Osofsky, MS Skelton, EF Claassen, JH Gibson, G MacManus-Driscoll, JL Malde, N Cohen, LF TI Simultaneous optimization of the linear and nonlinear microwave response of YBCO films and devices SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1998 Applied Superconductivity Conference CY SEP 13-18, 1998 CL PALM DESERT, CALIFORNIA ID HIGH-TEMPERATURE SUPERCONDUCTORS; THIN-FILMS; YBA2CU3O7-DELTA AB We present results of a systematic study of the effect of film deposition temperature on both the linear and nonlinear response of superconducting YBa2Cu3O7-delta (YBCO) thin films and devices at microwave frequencies. Measurements of the unpatterned films show that samples grown by pulsed laser deposition at a lower substrate temperature (740 degrees C) display a smaller low-temperature residual surface resistance compared to films grown at a higher substrate temperature (780 degrees C). However, the same films which display low residual surface resistance also show increased nonlinear effects (measured by third harmonic generation) at all temperatures. Analysis of these results suggests that the increased defects present in the films grown at the lower deposition temperature are responsible for both the lower surface resistance and the higher third harmonic generation observed in these samples. We discuss the consequences of these results for the simultaneous optimization of both linear and nonlinear microwave properties of HTS thin films and devices. C1 Natl Inst Stand & Technol, Boulder, CO 80303 USA. NTIA, Inst Telecommun Sci, Boulder, CO 80303 USA. USN, Res Lab, Washington, DC 20375 USA. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, Ctr Superconduct, London, England. RP Booth, JC (reprint author), Natl Inst Stand & Technol, 325 Broadway, Boulder, CO 80303 USA. RI Osofsky, Michael/A-1050-2010 NR 16 TC 23 Z9 23 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1999 VL 9 IS 2 BP 4176 EP 4180 DI 10.1109/77.783945 PN 3 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 225MC UT WOS:000081964500325 ER PT J AU Claassen, JH Adrian, S Soulen, RJ AF Claassen, JH Adrian, S Soulen, RJ TI Large non-linear kinetic inductance in superconductor/normal metal bilayer films SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 1998 Applied Superconductivity Conference CY SEP 13-18, 1998 CL PALM DESERT, CALIFORNIA AB We study the kinetic inductance in thin superconducting/normal metal (S/N) bilayer films where the penetration depth is greater than the S thickness. Using the two-coil mutual inductance method, we show that it is possible to estimate the dependence of kinetic inductance on sheet current density. It is found that, as expected from Ginzburg-Landau theory, the dependence is very weak in bare superconducting films. However in S/N bilayers of NbN/Al and Nb/Al the kinetic inductance can be smoothly varied over at least a 2:1 range by application of a dc transport current. It is proposed that this novel non-linearity could be exploited in some microwave applications. C1 USN, Res Lab, Washington, DC 20375 USA. RP Claassen, JH (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 7 TC 3 Z9 3 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 1999 VL 9 IS 2 BP 4189 EP 4192 DI 10.1109/77.783948 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 225MC UT WOS:000081964500328 ER PT J AU Stilwell, DJ Rugh, WJ AF Stilwell, DJ Rugh, WJ TI Interpolation of observer state feedback controllers for gain scheduling SO IEEE TRANSACTIONS ON AUTOMATIC CONTROL LA English DT Article DE gain scheduling; linear parameter-varying ID PARAMETER-VARYING SYSTEMS; DESIGN AB The authors propose a method of interpolating linear time-invariant controllers with observer state feedback structure in order to generate a continuously varying family of controllers that stabilizes a family of linear plants. Gain scheduling is a motivation for this work, and the interpolation method yields guidelines for the design of gain scheduled controllers. The method is illustrated with the design of a missile autopilot using loop-shaping H-infinity controllers. C1 USN Acad, Dept Syst Engn, Annapolis, MD 21402 USA. Johns Hopkins Univ, Dept Elect & Comp Engn, Baltimore, MD 21218 USA. RP Stilwell, DJ (reprint author), USN Acad, Dept Syst Engn, Annapolis, MD 21402 USA. NR 13 TC 77 Z9 80 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9286 J9 IEEE T AUTOMAT CONTR JI IEEE Trans. Autom. Control PD JUN PY 1999 VL 44 IS 6 BP 1225 EP 1229 DI 10.1109/9.769379 PG 5 WC Automation & Control Systems; Engineering, Electrical & Electronic SC Automation & Control Systems; Engineering GA 206BP UT WOS:000080856400014 ER PT J AU Last, HR Deeds, M Garvick, D Kavetsky, R Sandborn, PA Magrab, EB Gupta, SK AF Last, HR Deeds, M Garvick, D Kavetsky, R Sandborn, PA Magrab, EB Gupta, SK TI Nano-to-millimeter scale integrated systems SO IEEE TRANSACTIONS ON COMPONENTS AND PACKAGING TECHNOLOGIES LA English DT Article C1 USN, Ctr Surface Warfare, Indian Head, MD 20640 USA. Univ Maryland, CALCE Elect Prod & Syst Consortium, College Pk, MD 20742 USA. RP Last, HR (reprint author), USN, Ctr Surface Warfare, Indian Head, MD 20640 USA. NR 12 TC 8 Z9 8 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1521-3331 J9 IEEE T COMPON PACK T JI IEEE Trans. Compon. Packaging Technol. PD JUN PY 1999 VL 22 IS 2 BP 338 EP 343 DI 10.1109/6144.774758 PG 6 WC Engineering, Manufacturing; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 217VV UT WOS:000081520400030 ER PT J AU Kerfoot, IB Bresler, Y AF Kerfoot, IB Bresler, Y TI Theoretical analysis of multispectral image segmentation criteria SO IEEE TRANSACTIONS ON IMAGE PROCESSING LA English DT Article DE Landsat; Markov random field; minimum description length; multispectral; segmentation; stochastic; theoretical analysis ID RANDOM-FIELDS; OPTIMIZATION; RELAXATION; ALGORITHMS; PARALLEL AB Markov random field (MRF) image segmentation algorithms have been extensively studied, and have gained wide acceptance. However, almost all of the work on them has been experimental. This provides a good understanding of the performance of existing algorithms, but not a unified explanation of the significance of each component. To address this issue, we present a theoretical analysis of several MRF image segmentation criteria. Standard methods of signal detection and estimation are used in the theoretical analysis, which quantitatively predicts the performance at realistic noise levels. The analysis is decoupled into the problems of false alarm rate, parameter selection (Neyman-Pearson and receiver operating characteristics), detection threshold, expected a priori boundary roughness, and supervision. Only the performance inherent to a criterion, with perfect global optimization, is considered. The analysis indicates that boundary and region penalties are very useful, while distinct-mean penalties are of questionable merit. Region penalties are far more important for multispectral segmentation than for greyscale. This observation also holds for Gauss-Markov random fields, and for many separable withinclass pdf's. To validate the analysis, we present optimization algorithms for several criteria. Theoretical and experimental results agree fairly well. C1 USN, Undersea Warfare Ctr, Newport, RI 02841 USA. Univ Illinois, Dept Elect & Comp Engn, Urbana, IL 61801 USA. Univ Illinois, Coordinated Sci Lab, Urbana, IL 61801 USA. RP Kerfoot, IB (reprint author), USN, Undersea Warfare Ctr, Newport, RI 02841 USA. NR 41 TC 13 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 USA SN 1057-7149 J9 IEEE T IMAGE PROCESS JI IEEE Trans. Image Process. PD JUN PY 1999 VL 8 IS 6 BP 798 EP 820 DI 10.1109/83.766858 PG 23 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 201EJ UT WOS:000080581800005 PM 18267494 ER PT J AU Welch, TB Ziemer, RE AF Welch, TB Ziemer, RE TI Efficient simulation of coded MC-DS-CDMA systems SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article; Proceedings Paper CT IEEE Radio and Wireless Conference (RAWCON 98) CY AUG 09-12, 1998 CL COLORADO SPRINGS, COLORADO SP IEEE, Microwave Theory & Techn Soc, IEEE, Pikes Peak Sect DE DS-CDMA; error correction coding; MC-DS-CDMA; performance simulation; spread-spectrum communications; time-varying channels ID PERFORMANCE AB We use computer simulations to compare the performance improvements associated with coding on Gaussianized binary phase-shift keying (BPSK) multicarrier direct-sequence code-division multiple-access (MC-DS-CDMA) system and a non-Gaussianized differential phase-shift keying (DPSK)-MC-DS-CDMA system. The effects of coding on the Gaussianized system approach the performance of a coded BPSK system operating in a Gaussian channel while the non-Gaussianized system performance is approximately 4 dB from the coded DPSK system operating in a Gaussian channel. C1 USN Acad, Dept Elect Engn, Annapolis, MD 21402 USA. Univ Colorado, Dept Elect & Comp Engn, Colorado Springs, CO 80903 USA. RP Welch, TB (reprint author), USN Acad, Dept Elect Engn, Annapolis, MD 21402 USA. NR 16 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 USA SN 0018-9480 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD JUN PY 1999 VL 47 IS 6 BP 675 EP 680 DI 10.1109/22.769334 PN 1 PG 6 WC Engineering, Electrical & Electronic SC Engineering GA 207YA UT WOS:000080962300003 ER PT J AU Lynch, RS Willett, PK AF Lynch, RS Willett, PK TI Performance considerations for a combined information classification test using Dirichlet priors SO IEEE TRANSACTIONS ON SIGNAL PROCESSING LA English DT Article DE Bayesian; combining training and test data; discrete data; uniform prior ID EMPIRICALLY OBSERVED STATISTICS; SPEECH RECOGNITION AB The average probability of error is used to demonstrate performance of the combined Bayes test (CBT), which assumes a uniform Dirichlet prior for the symbol probabilities of each class. Performance of the CBT is compared with an uncombined maximum likelihood (ML) based test and with the Kolmogorov-Smirnov test. C1 USN, Undersea Warfare Ctr, Newport, RI 02841 USA. Univ Connecticut, Storrs, CT 06269 USA. RP Lynch, RS (reprint author), USN, Undersea Warfare Ctr, Newport, RI 02841 USA. OI Willett, Peter/0000-0001-8443-5586 NR 20 TC 16 Z9 16 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1053-587X J9 IEEE T SIGNAL PROCES JI IEEE Trans. Signal Process. PD JUN PY 1999 VL 47 IS 6 BP 1711 EP 1714 DI 10.1109/78.765145 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA 198KE UT WOS:000080422000021 ER PT J AU Mushrush, GW Beal, EJ Hardy, DR Hughes, JM Cummings, JC AF Mushrush, GW Beal, EJ Hardy, DR Hughes, JM Cummings, JC TI Jet fuel system icing inhibitors: Synthesis and characterization SO INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH LA English DT Article AB There have been no new literature papers dealing with jet fuel deicing additive replacements for the past 20 years. The current fuel system icing inhibitor additives, used by both the military and commercial aviation, are ethylene glycol monomethyl ether and diethylene glycol monomethyl ether. These deicing compounds are toxic at the concentrations that are required for effective deicing. This observation points to an immediate need for nontoxic, inexpensive, and biodegradable deicing compounds. The synthesis of polar sugar derivatives represents a viable alternative to glycol-based additives. The alternative deicing compounds reported in this paper are inexpensive and fuel stable and exhibit icing inhibitor characteristics similar to those of the presently used commercial materials. C1 USN, Res Lab, Div Chem, Fuels Sect,Mat Chem Branch, Washington, DC 20375 USA. George Mason Univ, Dept Chem, Fairfax, VA 22030 USA. Geocenters Inc, Ft Washington, MD 20749 USA. Naval Air Syst Command, Patuxent River, MD 20670 USA. RP Mushrush, GW (reprint author), USN, Res Lab, Div Chem, Fuels Sect,Mat Chem Branch, Code 6121,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 24 TC 14 Z9 14 U1 1 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0888-5885 J9 IND ENG CHEM RES JI Ind. Eng. Chem. Res. PD JUN PY 1999 VL 38 IS 6 BP 2497 EP 2502 DI 10.1021/ie9807755 PG 6 WC Engineering, Chemical SC Engineering GA 205NP UT WOS:000080827700041 ER PT J AU Brook, I Frazier, EH AF Brook, I Frazier, EH TI Aerobic and anaerobic microbiology of pyomyositis SO INFECTIOUS DISEASES IN CLINICAL PRACTICE LA English DT Article ID INFECTIONS; BACTERIA AB The aerobic and anaerobic microbiologic characteristics of pyomyositis were investigated through a retrospective review of microbiologic and clinical data at the U.S. Naval Hospital in Bethesda, Maryland. Microorganisms were isolated from eight abscesses. Only anaerobic organisms were recovered in three patients (37.5%), aerobic and facultatives only in three (37.5%), and mixed aerobic and anaerobic bacteria in two (25%). A total of 15 isolates were recovered (10 anaerobic, five aerobic or facultative). The isolates included three Peptostreptococcus species, three Staphylococcus aureus, two Bacteroides fragilis group, two Clostridium species, and one each of Escherichia coli, Streptococcus pyogenes, and Fusobacterium nucleatum. Predisposing conditions included trauma (three cases), malignancy (three), diabetes (one), and aplastic anemia (one). C1 USN Hosp, Dept Pediat, Bethesda, MD 20814 USA. USN Hosp, Dept Infect Dis, Bethesda, MD 20814 USA. RP Brook, I (reprint author), POB 70412, Chevy Chase, MD 20813 USA. NR 23 TC 1 Z9 1 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1056-9103 J9 INFECT DIS CLIN PRAC JI Infect. Dis. Clin. Pract. PD JUN-JUL PY 1999 VL 8 IS 5 BP 252 EP 256 DI 10.1097/00019048-199906000-00006 PG 5 WC Immunology; Infectious Diseases SC Immunology; Infectious Diseases GA 211GD UT WOS:000081151800009 ER PT J AU Macys, D AF Macys, D TI Opening remarks SO INHALATION TOXICOLOGY LA English DT Editorial Material C1 USN, Ctr Environm Hlth, Norfolk, VA USA. RP Macys, D (reprint author), Off Naval Res, Program Officer Med Sci & Technol Code 341, 800 N Quincy St, Arlington, VA 22217 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0895-8378 J9 INHAL TOXICOL JI Inhal. Toxicol. PD JUN-JUL PY 1999 VL 11 IS 6-7 BP 455 EP 457 DI 10.1080/089583799196862 PG 3 WC Toxicology SC Toxicology GA 212UX UT WOS:000081236900001 ER PT J AU Cheng, LY Hostetler, KY Gardner, MF Avila, CP Bergeron-Lynn, G Keefe, KS Wiley, CA Freeman, WR AF Cheng, LY Hostetler, KY Gardner, MF Avila, CP Bergeron-Lynn, G Keefe, KS Wiley, CA Freeman, WR TI Intravitreal toxicology in rabbits of two preparations of 1-O-octadecyl-sn-glycerol-3-phosphonoformate, a sustained-delivery anti-CMV drug SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Article ID IMMUNE-DEFICIENCY-SYNDROME; ACYCLOVIR DIPHOSPHATE DIMYRISTOYLGLYCEROL; ACQUIRED-IMMUNODEFICIENCY-SYNDROME; CYTOMEGALO-VIRUS RETINOPATHY; ENHANCED ANTIVIRAL ACTIVITY; GANCICLOVIR THERAPY; INFECTED CELLS; RETINITIS; AIDS; CIDOFOVIR AB PURPOSE. TO determine intraocular toxicity and efficacy of the lipid prodrug of foscarnet, 1-O-octadecyl-sn-glycerol-3-phosphonoformate (ODG-PFA), as a long-acting, nontoxic intravitreous injectable drug delivery system for cytomegalovirus (CMV) retinitis. METHODS. ODG-PFA was synthesized by coupling the phosphonate residue of PFA to the 3 hydroxyl of 1-O-octadecyl-sn-glycerol and formulated as micelles and Liposomes at concentrations so that, after injection into the rabbit vitreous, the resultant intravitreal concentrations were 0.2 mM, 0.63 mM, and 2 mM I in micellar formulation and 0.02 mM, 0.063 mM, 0.2 mM, and 0.63 mM for liposomal formulation. The compounds were injected, and toxicology evaluations were performed. RESULTS. Intravitreal injections of micellar ODG-PFA resulted in aggregation of the material in vitreous and variable local retinal damage. Intravitreal injections of the liposomal ODG-PFA revealed even dispersion of the compounds and a clear vitreous, using final concentration in the vitreous of 0.2 mM. Na intraocular toxicity was found with the 0.632 mM final concentration. The 50% inhibitory concentration (IC50) for CMV of ODG-PFA was 0.43 +/- 0.27 mu M, and the therapeutic index of ODG-PFA after intravitreal injection was estimated to be 1470.1. CONCLUSIONS. Lipid-derivatized foscarnet liposome formulations may be a useful long-acting delivery system for the therapy of CMV retinitis. C1 Univ Calif San Diego, Dept Ophthalmol, Shiley Eye Ctr, La Jolla, CA 92093 USA. Vet Adm Med Ctr, Dept Med, La Jolla, CA 90034 USA. USN Hosp, San Diego, CA 92134 USA. Univ Pittsburgh, Dept Pathol, Pittsburgh, PA 15260 USA. RP Freeman, WR (reprint author), Univ Calif San Diego, Dept Ophthalmol, Shiley Eye Ctr, 9415 Campus Point Dr, La Jolla, CA 92093 USA. FU NEI NIH HHS [EYO7366, EY11832] NR 41 TC 21 Z9 22 U1 0 U2 1 PU ASSOC RESEARCH VISION OPHTHALMOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD JUN PY 1999 VL 40 IS 7 BP 1487 EP 1495 PG 9 WC Ophthalmology SC Ophthalmology GA 200GU UT WOS:000080531900021 PM 10359331 ER PT J AU Georgiou, IT Schwartz, I Emaci, E Vakakis, A AF Georgiou, IT Schwartz, I Emaci, E Vakakis, A TI Interaction between slow and fast oscillations in an infinite degree-of-freedom linear system coupled to a nonlinear subsystem: Theory and experiment SO JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME LA English DT Article ID SINGULAR PERTURBATION-THEORY; DYNAMICS; CHAOS AB The interaction dynamics of a cantilever linear beam coupled to a nonlinear pendulum, a prototype for linear/nonlinear coupled structures of infinite degrees-of-freedom, has been studied analytically and experimentally. The spatio-temporal characteristics of the dynamics is analyzed by using tools from geometric singular perturbation theory and proper orthogonal decompositions. Over a wide range of coupling between the linear beam and the nonlinear pendulum, the coupled dynamics is dominated by three proper orthogonal (PO) modes. The first two dominant PO modes stem from those characterizing the reduced slow free dynamics of the stiff/soft (weakly coupled) system. The third mode appears in all interactions and stems from the reduced fast free dynamics. The interaction creates periodic and quasi-periodic motions that reduce dramatically the forced resonant dynamics in the linear substructure These regular Motions are characterized by four PO modes. The irregular interaction dynamics consists of low-dimensional and high-dimensional chaotic motions characterized by three PO modes and six to seven PO modes, respectively. Experimental tests are also carried out and there is satisfactory agreement with theoretical predictions. C1 USN, Res Lab, Special Project Nonlinear Sci, Washington, DC 20375 USA. Univ Illinois, Dept Mech & Ind Engn, Urbana, IL 61801 USA. RP Georgiou, IT (reprint author), Sci Applicat Int Corp, Mclean, VA 22102 USA. RI Schwartz, Ira/A-8073-2009 NR 24 TC 30 Z9 30 U1 0 U2 3 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0021-8936 J9 J APPL MECH-T ASME JI J. Appl. Mech.-Trans. ASME PD JUN PY 1999 VL 66 IS 2 BP 448 EP 459 DI 10.1115/1.2791069 PG 12 WC Mechanics SC Mechanics GA 217AF UT WOS:000081476100022 ER PT J AU Srivastava, AK Hurben, MJ Wittenauer, MA Kabos, P Patton, CE Ramesh, R Dorsey, PC Chrisey, DB AF Srivastava, AK Hurben, MJ Wittenauer, MA Kabos, P Patton, CE Ramesh, R Dorsey, PC Chrisey, DB TI Angle dependence of the ferromagnetic resonance linewidth and two magnon losses in pulsed laser deposited films of yttrium iron garnet, MnZn ferrite, and NiZn ferrite SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID STRUCTURAL-PROPERTIES; THIN-FILMS AB Shorted waveguide ferromagnetic resonance (FMR) measurements were made at 9.5 GHz for pulsed laser deposited yttrium iron garnet (YIG), MnZn ferrite, and NiZn ferrite films with thicknesses of 1.8, 0.5, and 1.5 mu m, respectively. The FMR field versus the field angle confirmed the operational assumption of a uniform mode response. For the YIG, the linewidth was 10 Oe when the external field and magnetization vectors were perpendicular to the disk (perpendicular FMR) and increased smoothly to a maximum value of 27 Oe when the field and magnetization were in the film plane (parallel FMR). For the MnZn, the linewidth was 49 Oe at perpendicular FMR, increased with the angle between the film normal and the external field to a broad maximum of 80 Oe at 35 degrees, and then dropped to 65 Oe at parallel FMR. For the NiZn, the linewidth was 310 Oe at perpendicular FMR, increased with the field angle to a broad maximum of 1530 Oe at 45 degrees, and then dropped to 960 Oe at parallel FMR. The linewidths were larger than predicted for reasonable values of the Landau-Lifshitz damping and showed angle dependences which indicated nonintrinsic contributions to the loss. Two magnon scattering was used to model these linewidth differences. The angle dependences of the excess linewidths show qualitative agreement with the two magnon predictions, with inhomogeneity sizes in the submicron range and volume fractions below 1%. (C) 1999 American Institute of Physics. [S0021-8979(99)00609-X]. C1 Colorado State Univ, Dept Phys, Ft Collins, CO 80523 USA. Univ Maryland, Dept Mat Engn, College Pk, MD 20742 USA. USN, Res Lab, Washington, DC 20375 USA. RP Srivastava, AK (reprint author), Colorado State Univ, Dept Phys, Ft Collins, CO 80523 USA. NR 28 TC 25 Z9 26 U1 0 U2 16 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 1 PY 1999 VL 85 IS 11 BP 7838 EP 7848 DI 10.1063/1.370595 PG 11 WC Physics, Applied SC Physics GA 197FL UT WOS:000080354300050 ER PT J AU Ball, R Lehner, CE Parker, EC AF Ball, R Lehner, CE Parker, EC TI Predicting risk of decompression sickness in humans from outcomes in sheep SO JOURNAL OF APPLIED PHYSIOLOGY LA English DT Article DE risk prediction; allometric scaling; decompression illness; hyperbaric; diving ID MODEL AB In animals, the response to decompression scales as a power of species body mass. Consequently, decompression sickness (DCS) risk in humans should be well predicted from an animal model with a body mass comparable to humans. No-stop decompression outcomes in compressed air and nitrogen-oxygen dives with sheep (n = 394 dives, 14.5% DCS) and humans (n = 463 dives, 4.5% DCS) were used with linear-exponential, probabilistic modeling to test this hypothesis. Scaling the response parameters of this model between species (without accounting for body mass), while estimating tissue-compartment kinetic parameters from combined human and sheep data, predicts combined risk better, based on log likelihood, than do separate sheep and human models, a combined model without scaling, and a kinetic-scaled model. These findings provide a practical tool for estimating DCS risk in humans from outcomes in sheep, especially in decompression profiles too risky to test with humans. This model supports the hypothesis that species of similar body mass have similar DCS risk. C1 USN, Med Res Inst, Bethesda, MD 20889 USA. Univ Wisconsin, Dept Surg Sci, Madison, WI 53706 USA. RP Ball, R (reprint author), US FDA, CBER, DBE, HFM 220, 1401 Rockville Pike, Rockville, MD 20852 USA. NR 19 TC 12 Z9 12 U1 0 U2 0 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 8750-7587 J9 J APPL PHYSIOL JI J. Appl. Physiol. PD JUN PY 1999 VL 86 IS 6 BP 1920 EP 1929 PG 10 WC Physiology; Sport Sciences SC Physiology; Sport Sciences GA 204TV UT WOS:000080781400029 PM 10368357 ER PT J AU Kimmel, EC Carpenter, RL Reboulet, JE Still, KR AF Kimmel, EC Carpenter, RL Reboulet, JE Still, KR TI A physiological model for predicting carboxyhemoglobin formation from exposure to carbon monoxide in rats SO JOURNAL OF APPLIED PHYSIOLOGY LA English DT Article DE carbon monoxide exposure; carboxyhemoglobin formation prediction; numerical models; Coburn-Forster-Kane equation ID INHALATION AB A time-dependent simulation model, based on the Coburn-Forster-Kane equation, was written in Advanced Continuous Simulation Language to predict carboxyhemoglobin (HbCO) formation and dissociation in F-344 rats during and after exposure to 500 parts/million CO for 1 h. Blood-gas analysis and CO-oximetry were performed on samples collected during exposure and off-gassing of CO. Volume displacement plethysmography was used to measure minute ventilation (VE) during exposure. CO diffusing capacity in the lung (DLCO) was also measured. Other model parameters measured in the animals included blood pH, total blood volume, and Hb concentration. Comparisons between model predictions using values for (V) over dot(E), DLCO, and the Haldane coefficient cited in the literature and predictions using measured (V) over dot(E), DLCO, and calculated Haldane coefficient for individual animals were made. General model predictions using values for model parameters derived from the literature agreed with published HbCO values by a factor of 0.987 but failed to simulate experimental data. On average, the general model overpredicted measured HbCO level by nearly 9%. A specific model using the means of measured variables predicted HbCO concentration within a factor of 0.993. When experimentally observed parameter fluctuations were included, the specific model predictions reflected experimental effects on HbCO formation. C1 USN, Hlth Res Ctr Detachment Toxicol, Wright Patterson AFB, OH 45433 USA. Geo Ctr Inc, Newton, MA 02159 USA. RP Kimmel, EC (reprint author), USN, Hlth Res Ctr Detachment Toxicol, Bldg 433,2612 5th St, Wright Patterson AFB, OH 45433 USA. NR 32 TC 12 Z9 12 U1 0 U2 0 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 8750-7587 J9 J APPL PHYSIOL JI J. Appl. Physiol. PD JUN PY 1999 VL 86 IS 6 BP 1977 EP 1983 PG 7 WC Physiology; Sport Sciences SC Physiology; Sport Sciences GA 204TV UT WOS:000080781400036 PM 10368364 ER PT J AU Chu, PC Wang, QQ Bourke, RH AF Chu, PC Wang, QQ Bourke, RH TI A geometric model for the Beaufort Chukchi Sea thermohaline structure SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID MIXED-LAYER AB A geometric model has been developed for analyzing observed Beaufort/Chukchi Sea temperature and salinity profiles based on their geometric features. It contains four major components: (a) a nonhomogeneous mesh difference scheme for second derivatives partial derivative(2)T(z(k))/partial derivative z(2) and partial derivative(2)S(z(k))/partial derivative z(2) at each data point (z(k), T-k, S-k); (b) a set of key depths (depths of mixed layer, upper and lower thermoclines and haloclines, and deep layers) determined mostly by the geometric features of profiles, such as depths of minimum and maximum of partial derivative(2)T(z(k))/partial derivative z(2) and partial derivative(2)S(z(k))/partial derivative z(2) for shelf water and upper portion deep water; (c) modeled profiles (T) over cap(z(k)) and (S) over cap(z(k)), which are linearly interpolated from observed T, S values at the key depths; and (d) statistical tests for accepting [(T) over cap(z(k)), (S) over cap(z(k))] as a good representative of (z(k), T-k, S-k). The output of this geometric model is a set of major characteristics of each profile: sea surface temperature (salinity), mixed layer depth, upper- and lower-thermocline (halocline) depths, thermocline (halocline) temperature (salinity) gradient, and deep layer stratification. Analyzing 3562 Beaufort/Chukchi Sea historical (1970-93) temperature and salinity profiles from the Naval Oceanographic Office's Master Oceanographic Observation Data Set by this geometric model, the Beaufort/Chukchi Sea thermohaline field reveals a dual structure: one layer (vertically uniform) on the continental shelf (depth < 150 m) during winter and multiple layers (mixed layer, thermocline/halocline, sublayer) during summer. Strong seasonal variations were also found in mixed layer depth, upper thermocline/halocline depth, and strength. C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. Nanjing Inst Meteorol, Dept Atmospher Sci, Nanjing, Peoples R China. RP Wang, QQ (reprint author), USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. NR 9 TC 12 Z9 12 U1 1 U2 4 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD JUN PY 1999 VL 16 IS 6 BP 613 EP 632 DI 10.1175/1520-0426(1999)016<0613:AGMFTB>2.0.CO;2 PG 20 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 205BZ UT WOS:000080802600001 ER PT J AU Kelly, TL Neri, DF Grill, JT Ryman, D Hunt, PD Dijk, DJ Shanahan, TL Czeisler, CA AF Kelly, TL Neri, DF Grill, JT Ryman, D Hunt, PD Dijk, DJ Shanahan, TL Czeisler, CA TI Nonentrained circadian rhythms of melatonin in submariners scheduled to an 18-hour day SO JOURNAL OF BIOLOGICAL RHYTHMS LA English DT Article DE circadian rhythms; forced desynchrony; free running; entrainment; tau; submarines; bright light; work schedule; melatonin ID BLIND MAN; LIGHT; HUMANS; SLEEP; TEMPERATURE; PACEMAKER; PHASE; WORK AB The human circadian timing system has previously been shown to free run with a period slightly longer than 24 h in subjects living in the laboratory under conditions of forced desynchrony. In forced desynchrony, subjects are shielded from bright light and periodic time cues and are required to live on a day length outside the range of circadian entrainment. The work schedule used for most personnel aboard American submarines is 6 h on duty alternating with 12 h off duty. This imposed 18-h cycle is too short for human circadian synchronization, especially given that there is no bright-light exposure aboard submarines. However, crew members are exposed to 24-h stimuli that could mediate synchronization, such as clocks and social contacts with personnel who are living on a 24-h schedule. The authors investigated circadian rhythms of salivary melatonin in 20 crew members during a prolonged voyage on a Trident nuclear submarine. The authors found that in crew members living on the 18-h duty cycle, the endogenous rhythm of melatonin showed an average period of 24.35 h (n = 12, SD = 0.18 h). These data indicate that social contacts and knowledge of clock time are insufficient for entrainment to a 24-h period in personnel living by an 18-h rest-activity cycle aboard a submarine. C1 Harvard Univ, Sch Med, Dept Med, Div Endocrinol,Circadian Neuroendocrine & Sleep D, Boston, MA 02115 USA. USN, Hlth Res Ctr, San Diego, CA 92186 USA. USN, Med Ctr Portsmouth, Portsmouth, VA 23708 USA. RP Czeisler, CA (reprint author), Harvard Univ, Sch Med, Dept Med, Div Endocrinol,Circadian Neuroendocrine & Sleep D, Boston, MA 02115 USA. RI Dijk, Derk-Jan/D-8387-2011; Neri, Dario/P-4368-2016 NR 22 TC 31 Z9 32 U1 1 U2 3 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 USA SN 0748-7304 J9 J BIOL RHYTHM JI J. Biol. Rhythms PD JUN PY 1999 VL 14 IS 3 BP 190 EP 196 DI 10.1177/074873099129000597 PG 7 WC Biology; Physiology SC Life Sciences & Biomedicine - Other Topics; Physiology GA 256AP UT WOS:000083702700004 PM 10452330 ER PT J AU Koubek, E AF Koubek, E TI Gelatinous aluminum hydroxide - Reply SO JOURNAL OF CHEMICAL EDUCATION LA English DT Letter C1 USN Acad, Dept Chem, Annapolis, MD 21402 USA. RP Koubek, E (reprint author), USN Acad, Dept Chem, Annapolis, MD 21402 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-9584 J9 J CHEM EDUC JI J. Chem. Educ. PD JUN PY 1999 VL 76 IS 6 BP 756 EP 756 PG 1 WC Chemistry, Multidisciplinary; Education, Scientific Disciplines SC Chemistry; Education & Educational Research GA 196HJ UT WOS:000080302700012 ER PT J AU Ngai, KL AF Ngai, KL TI Properties of the constant loss in ionically conducting glasses, melts, and crystals SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID NUCLEAR-SPIN RELAXATION; ALKALI OXIDE GLASSES; AC-CONDUCTIVITY; ELECTRICAL-CONDUCTIVITY; DIELECTRIC-RELAXATION; FREQUENCY-DEPENDENCE; CHALCOGENIDE GLASSES; DECAY FUNCTION; POWER-LAW; ION AB A frequency independent or nearly frequency independent contribution to the dielectric loss is present in all ionic conductors independent of the chemical and physical structures. An exhaustive collection of dielectric relaxation data of glassy, crystalline, and molten ionic conductors are analyzed to obtain the magnitudes of their constant losses and the dependencies on temperature, ion density, ion mass, dc conductivity activation energy, dc conductivity level, the nonexponential conductivity relaxation parameter beta, the mixed alkali effect, and the decoupling index R-tau. Trends of changes in the constant loss when modifying the structure of the glassy matrix or mixing two different alkali ions are also found. In a glass-forming molten salt, 0.4Ca(NO3)(2 .)0.6KNO(3), the constant loss turns out to have approximately the same temperature dependence as the mean square displacement of the ions obtained by elastic neutron scattering measurement. All dependencies and properties found indicate that the physical origin of the constant loss may be traced to the displacement of the ions in their local librational or vibrational motion, but anharmonicity is not a necessary ingredient. (C) 1999 American Institute of Physics. [S0021-9606(99)71021-4]. C1 USN, Res Lab, Washington, DC 20375 USA. Tokyo Inst Technol, Fac Sci, Tokyo 1528551, Japan. RP Ngai, KL (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 67 TC 143 Z9 143 U1 0 U2 15 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUN 1 PY 1999 VL 110 IS 21 BP 10576 EP 10584 DI 10.1063/1.478989 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 197MT UT WOS:000080369100039 ER PT J AU Hudspeth, MK Gerardo, SH Maiden, MFJ Citron, DM Goldstein, EJC AF Hudspeth, MK Gerardo, SH Maiden, MFJ Citron, DM Goldstein, EJC TI Characterization of Bacteroides forsythus strains from cat and dog bite wounds in humans and comparison with monkey and human oral strains SO JOURNAL OF CLINICAL MICROBIOLOGY LA English DT Article ID GEL-ELECTROPHORESIS; SDS-PAGE; IDENTIFICATION AB Bacteroides forsythus strains recovered from cat and dog bite wound infections in humans (n = 3), monkey oral strains (n = 3), and the human oral ATCC 43037 type strain were characterized by using phenotypic characteristics, enzymatic tests, whole cell fatty acid analysis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis, PCR fingerprinting, and 16S rDNA (genes coding for rRNA) sequencing. All three bite wound isolates grew on brucella agar supplemented with 5% sheep blood, vitamin K-1, and hemin, These strains, unlike the ATCC strain and previously described monkey oral and human clinical strains, did not require N-acetylmuramic acid supplementation for growth as pure cultures. However, their phenotypic characteristics, except for catalase production, were similar to those of previously identified strains. PCR fingerprinting analysis showed differences in band patterns from the ATCC strain. Also, SDS-PAGE and whole cell fatty acid analysis indicated that the dog and cat bite wound strains were similar but not identical to the human B. forsythus ATCC 43037 type strain and the monkey oral strains. The rDNA sequence analysis indicated that the three bite wound isolates had 99.93% homology with each other and 98.9 and 99.22% homology with the human ATCC 43037 and monkey oral strains, respectively, These results suggest that there are host-specific variations within each group. C1 Univ Calif Los Angeles, Med Ctr, R M Alden Res Lab, Santa Monica, CA 90404 USA. USN, Hlth Res Ctr, San Diego, CA 92186 USA. Forsyth Dent Ctr, Dept Periodontal Microbiol, Boston, MA 02115 USA. Univ Calif Los Angeles, Sch Med, Los Angeles, CA 90024 USA. RP Goldstein, EJC (reprint author), Univ Calif Los Angeles, Med Ctr, R M Alden Res Lab, 1250 16th St, Santa Monica, CA 90404 USA. NR 17 TC 8 Z9 8 U1 0 U2 1 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0095-1137 J9 J CLIN MICROBIOL JI J. Clin. Microbiol. PD JUN PY 1999 VL 37 IS 6 BP 2003 EP 2006 PG 4 WC Microbiology SC Microbiology GA 197BN UT WOS:000080344900060 PM 10325363 ER PT J AU Tarman, GJ Lenert, JT Hall, L Kane, CJ AF Tarman, GJ Lenert, JT Hall, L Kane, CJ TI Holmium : YAG laser lithotripsy of intrahepatic biliary calculi SO JOURNAL OF ENDOUROLOGY LA English DT Article ID ELECTROHYDRAULIC LITHOTRIPSY; HEPATOLITHIASIS; MANAGEMENT; STONES AB The holmium:YAG laser has been used effectively for a wide variety of urinary calculi. No cases have been reported of its in vivo use in the biliary system. In this report, we describe its utility in intracorporeal lithotripsy of intrahepatic biliary stones and the urologist's role in providing expertise in small-caliber endoscopy and lithotripsy to other disciplines. C1 USN, San Diego Med Ctr, Dept Urol, San Diego, CA 92152 USA. USN, San Diego Med Ctr, Dept Gen Surg, San Diego, CA 92152 USA. USN, San Diego Med Ctr, Dept Radiol, San Diego, CA 92152 USA. RP Tarman, GJ (reprint author), USN, San Diego Med Ctr, Dept Clin Invest, 34800 Bob Wilson Dr,Suite 5, San Diego, CA 92134 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 USA SN 0892-7790 J9 J ENDOUROL JI J. Endourol. PD JUN PY 1999 VL 13 IS 5 BP 381 EP 383 DI 10.1089/end.1999.13.381 PG 3 WC Urology & Nephrology SC Urology & Nephrology GA 221EH UT WOS:000081710700014 PM 10446802 ER PT J AU Palmer, SC Shelton, SV AF Palmer, SC Shelton, SV TI Sensitivity analysis of absorption cycle fluid thermodynamic properties SO JOURNAL OF ENERGY RESOURCES TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article AB Absorption heat pump technology may be improved by new cycle configurations by new working fluids. In this study, the effect of hypothetical working fluids on performance improvement is explored. The performance of two cycles is studied using three fluid property sources for ammonia/water, i.e., curve-fit experimental data, an ideal solution model, and the Peng-Robinson equation of stare model. The models require only minimal fundamental thermodynamic property, data for the two pure components, This allows investigation into the influence of each fundamental property on cycle performance, providing insight into desirable properties for new absorption fluid pairs. Variations of fundamental fluid properties are used as input to the models, showing that the volatilities of the refrigerant and absorbent have the greatest effect on cycle performance. C1 USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. RP Palmer, SC (reprint author), USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. NR 19 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 USA SN 0195-0738 J9 J ENERG RESOUR-ASME JI J. Energy Resour. Technol.-Trans. ASME PD JUN PY 1999 VL 121 IS 2 BP 137 EP 142 DI 10.1115/1.2795069 PG 6 WC Energy & Fuels SC Energy & Fuels GA 206ZA UT WOS:000080909600013 ER PT J AU Carter, R Sibert, L Templeman, J Ballas, J AF Carter, R Sibert, L Templeman, J Ballas, J TI Luminous backgrounds and frames affect gray scale lightness, threshold, and suprathreshold discriminations SO JOURNAL OF EXPERIMENTAL PSYCHOLOGY-APPLIED LA English DT Article ID CONTRAST; PERFORMANCE; BRIGHTNESS; LUMINANCE AB Gray scale appearance of a target is affected by the target luminance, the luminance of the background area immediately surrounding the target, and the luminance of the wider area that frames the background. Increasing the framing luminance of an image reduces the lightness appearance of the entire image and increases the threshold for low-luminance features in the image. Background luminance enhances suprathreshold discrimination of targets with luminances similar to the background luminance. Surprisingly, frame luminance does not affect the number of discriminable suprathreshold levels except for a slight enhancement due to a dark frame at the lowest background and target luminances. Medical and other applications are discussed. C1 USN, Res Lab, Div Informat Technol, Washington, DC 20375 USA. New Jersey Inst Technol, Grant & Contract Serv, Newark, NJ 07102 USA. RP Sibert, L (reprint author), USN, Res Lab, Div Informat Technol, Code 5513,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 35 TC 3 Z9 3 U1 0 U2 0 PU AMER PSYCHOLOGICAL ASSOC PI WASHINGTON PA 750 FIRST ST NE, WASHINGTON, DC 20002-4242 USA SN 1076-898X J9 J EXP PSYCHOL-APPL JI J. Exp. Psychol.-Appl. PD JUN PY 1999 VL 5 IS 2 BP 190 EP 204 DI 10.1037/1076-898X.5.2.190 PG 15 WC Psychology, Applied SC Psychology GA 207JK UT WOS:000080933600005 ER PT J AU Bandyopadhyay, PR Nedderman, WH Dick, JL AF Bandyopadhyay, PR Nedderman, WH Dick, JL TI Biologically-inspired bodies under surface waves - Part 1: Load measurements SO JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article AB Measurements have been carried out in a tow tank on cylindrical bodies submerged in proximity of traveling surface waves. Two bodies are considered: a reference plain cylinder and another cylinder containing a pair of wings (or hydrofoils) below the cylinder, not above. The latter body owes its origin to certain species of fish which has small wings for maneuverability. The wavelength of the surface waves (lambda) is of the order of the cylinder length (L) or higher (1 < lambda/L < 10). Temporal measurements of axial and vertical forces and pitching moments, phase matched to the surface elevation of traveling waves, have been carried out. The time periods of the waves and depth of water pertain to deep water and intermediate depth waves. The forces and moments exhibit characteristic phase relationship with water elevation. Towing affects only vertical forces in the speed range of a to 1 m/s. The effect of towing and surface waves an vertical forces is roughly additive. Within the low speed range of rowing evaluated, the effects of surface waves dominate those of towing. The presence of the hydrofoil and intermediate depth waves bring in some additional effects which are not well understood. In intermediate depth waves, a small plain cylinder may encounter a resonance with traveling waves which can be averted by attaching a pair of small wings to dampen pitching moment and make it speed invariant, although at a cost of increased vertical forces. C1 USN, Undersea Warfare Ctr, Newport, RI 02841 USA. RP Bandyopadhyay, PR (reprint author), USN, Undersea Warfare Ctr, Newport, RI 02841 USA. NR 13 TC 11 Z9 11 U1 0 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0098-2202 J9 J FLUID ENG-T ASME JI J. Fluids Eng.-Trans. ASME PD JUN PY 1999 VL 121 IS 2 BP 469 EP 478 DI 10.1115/1.2822233 PG 10 WC Engineering, Mechanical SC Engineering GA 210ZT UT WOS:000081136000037 ER PT J AU Bandyopadhyay, PR Singh, SN Chockalingam, F AF Bandyopadhyay, PR Singh, SN Chockalingam, F TI Biologically-inspired bodies under surface waves - Part 2: Theoretical control of maneuvering SO JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID UNDERWATER VEHICLES; OSCILLATING FOILS; FISH AB The theoretical control of low-speed maneuvering of small underwater vehicles in the dive using dorsal and caudal fin-based control surfaces is considered. The two dorsal are long and are actually mounted in the horizontal plane. The caudal fin is also horizontal and is akin to the fluke of a whale. Dorsal-like fins mounted on a flow aligned vehicle produce a normal force when they are cambered. Using such a device, depth control can be accomplished. A flapping foil device mounted at the end of the tailcone of the vehicle produces vehicle motion that is somewhat similar to the motion produced by the caudal fins of fish. The moment produced by the flapping foils is used here for pitch angle control. A continuous adaptive sliding mode control law is derived for depth control via the dorsal fins in the presence of surface waves. The flapping Soils have periodic motion and they can produce only periodic forces. A discrete adaptive predictive control law is designed for varying the maximum tip excursion of the foils in each cycle for the pitch angle control and Sor the attenuation of disturbance caused by waves. Strouhal number of the foils is the key control variable. The derivation of control laws requires only imprecise knowledge of the hydrodynamic parameters and large uncertainty in system parameters is allowed. In the closed-loop system, depth trajectory tracking and pitch angle control are accomplished using caudal and dorsal fin-based control surfaces in the presence of system parameter uncertainty and surface waves. A control law for the trajectory control of depth and regulation of the pitch angle is also presented, which uses only the dorsal fins and simulation results are presented to show the controller performance. C1 USN, Undersea Warfare Ctr, Newport, RI 02841 USA. Univ Nevada, Dept Elect & Comp Engn, Las Vegas, NV 89154 USA. RP Bandyopadhyay, PR (reprint author), USN, Undersea Warfare Ctr, Newport, RI 02841 USA. NR 25 TC 12 Z9 12 U1 1 U2 3 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0098-2202 J9 J FLUID ENG-T ASME JI J. Fluids Eng.-Trans. ASME PD JUN PY 1999 VL 121 IS 2 BP 479 EP 487 DI 10.1115/1.2822234 PG 9 WC Engineering, Mechanical SC Engineering GA 210ZT UT WOS:000081136000038 ER PT J AU Walker, DN Amatucci, WE Bowles, JH Fernsler, RF Siefring, CL Antoniades, JA Keskinen, MJ AF Walker, DN Amatucci, WE Bowles, JH Fernsler, RF Siefring, CL Antoniades, JA Keskinen, MJ TI Discharging spacecraft through neutral gas release: Experiment and theory SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID MICROWAVE PLASMA SOURCE; MAGNETIC-FIELD; VOLTAGE; IONOSPHERE; PAYLOAD; SHEATH; FLIGHT; WAVES AB We describe experimental and theoretical research related to the mitigation of spacecraft charging by the release of neutral gas through specially designed nozzles. The experiments were conducted in the large Space Physics Simulation Chamber (SPSC) at the Naval Research Laboratory. A realistic near-Earth space environment can be simulated in this device for which minimum scaling needs to be performed to relate the data to space plasma regimes. The environment of the SPSC is similar to that encountered by spacecraft ill low Earth orbit. The experimental arrangement consists of an aluminum cylinder which can be biased to high voltage (0.4 < V < 10 kV). The cylinder incorporates a neutral gas release valve designed for millisecond release times, a pressure-regulated neutral gas reservoir, and variable Mach number nozzles. After the cylinder is charged to high voltage the neutral gas is released, inducing a breakdown of the gas in the strong electric field about the cylinder. Collection of ions from the newly created dense plasma, along with secondary electron emission from the cylinder surface, provides the return current necessary for grounding the body. We treat the breakdown theoretically as a Townsend discharge and use the fundamental assumption of exponential electron growth as one proceeds from the cathode toward the anode during neutral gas breakdown. In addition, the nozzle release of neutral gas is modeled, and a simple linear spatial dependence of the applied potential is assumed. This basic model produces quite good results when compared to the experiment. C1 USN, Res Lab, Div Plasma Phys, Charged Particle Phys Branch, Washington, DC 20375 USA. USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Walker, DN (reprint author), USN, Res Lab, Div Plasma Phys, Charged Particle Phys Branch, Washington, DC 20375 USA. NR 35 TC 2 Z9 2 U1 1 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD JUN 1 PY 1999 VL 104 IS A6 BP 12473 EP 12485 DI 10.1029/1998JA900172 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 201MY UT WOS:000080600400020 ER PT J AU St Cyr, OC Burkepile, JT Hundhausen, AJ Lecinski, AR AF St Cyr, OC Burkepile, JT Hundhausen, AJ Lecinski, AR TI A comparison of ground-based and spacecraft observations of coronal mass ejections from 1980-1989 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID SMM OBSERVATIONS; WHITE-LIGHT; TRANSIENT; SPEEDS AB We report here an analysis of observations of solar coronal mass ejections (CMEs) acquired in white light by the Mark III (MK3) K coronameter at Mauna Loa Solar Observatory between 1980 and 1989. Statistical properties of the locations, sizes, and speeds of these events are described. These properties are compared to those in the two other white light CME catalogs from the 1980s, the CMEs observed by the Solwind and SMM spaceborne coronagraphs, and relatively good statistical agreement is found between the three data sets taken over the entire period of observation. A detailed examination was performed for the 141 MK3 CMEs that were also observed by SMM. Virtually all (93%) of the CMEs detected low in the corona by the MK3 instrument were observed to travel out of the SMM field of view, into interplanetary space. The average width of CMEs in the MK3 field of view was 120 smaller than that measured in SMM, and we interpret this statistic as an indication of some increase in size as CMEs move outward through the corona. For a subset of 55 of those mass ejections we were able to combine detailed observations from both MK3 and SMM. Using the combined measurements, we were able to detect and to quantify the initial period of acceleration in a much larger fraction (61%) of the features than was possible from either MK3 alone (9%) or SMM alone (21%). The acceleration was positive for 87% of those features, with an average (median) value of +0.264 km s(-2) (+0.044 km s(-2)). A distinction in terms of association with other forms of solar activity was also evident in this analysis: 55% of the CMEs associated with active regions moved with constant speed, but 82% of the features associated with the eruption of solitary prominences moved with constant acceleration. Also, the average speed for CMEs associated with active regions was significantly faster than those with prominence association (955 versus 411 km s(-1)). The detection of positive acceleration demonstrates that the forces propelling the CME continue to dominate these events, at least through the altitudes covered by the MK3 and SMM fields of view. C1 NASA, Goddard Space Flight Ctr, LASCO, SOHO,USN,Res Lab,Computat Phys Inc, Greenbelt, MD 20771 USA. Natl Ctr Atmospher Res, High Altitude Observ, Boulder, CO 80301 USA. RP St Cyr, OC (reprint author), NASA, Goddard Space Flight Ctr, LASCO, SOHO,USN,Res Lab,Computat Phys Inc, Code 682-3, Greenbelt, MD 20771 USA. NR 32 TC 133 Z9 134 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD JUN 1 PY 1999 VL 104 IS A6 BP 12493 EP 12506 DI 10.1029/1999JA900045 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 201MY UT WOS:000080600400023 ER PT J AU Maia, D Vourlidas, A Pick, M Howard, R Schwenn, R Magalhaes, A AF Maia, D Vourlidas, A Pick, M Howard, R Schwenn, R Magalhaes, A TI Radio signatures of a fast coronal mass ejection development on November 6, 1997 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID JOINT NANCAY RADIOHELIOGRAPH; LASCO OBSERVATIONS; EVENT; ULYSSES AB The Oporto radiospectrograph and the Nancay radioheliograph recorded a radio event on November 6, 1997, closely related in time with a flare on National Oceanic and Atmospheric Administration (NOAA) active region 8100. At the beginning: of the event the radio sources are located on a rather small volume in the vicinity of the flare site. In a timescale df only a few minutes the radio emission sites spread over a large volume in the corona, covering a range of 100 degrees in heliolatitude. During the period of the radio event the Large Angle and Spectrometric Coronagraph (LASCO) on board the Solar and Heliospheric Observatory (SOHO) observed an extremely fast coronal mass ejection (CME), with a velocity around 2000 km s(-1) This CME presents the particularity of having a fast lateral expansion, giving it a shape reminiscent of a "coat hanger." There is a very good association between the latitudinal extent and time development of the CME seen by LASCO and the radio sources recorded by the radio instruments. C1 Observ Paris, DASOP, Sect Meudon, CNRS,UMR 8645, F-92195 Meudon, France. USN, Res Lab, Washington, DC 20375 USA. Observ Astron Monte Virgem, Oporto, Portugal. Max Planck Inst Aeron, D-37189 Katlenburg Lindau, Germany. George Mason Univ, Inst Computat Sci & Informat, Fairfax, VA 22030 USA. Univ Lisbon, Fac Ciencias, Lisbon, Portugal. RP Maia, D (reprint author), Observ Paris, DASOP, Sect Meudon, CNRS,UMR 8645, 5 Pl Jules Janssen, F-92195 Meudon, France. RI Vourlidas, Angelos/C-8231-2009; OI Vourlidas, Angelos/0000-0002-8164-5948; Maia, Dalmiro/0000-0001-7855-1919 NR 18 TC 73 Z9 74 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD JUN 1 PY 1999 VL 104 IS A6 BP 12507 EP 12513 DI 10.1029/1999JA900033 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 201MY UT WOS:000080600400024 ER PT J AU Knowles, S Meier, RR Gustafson, BAS Giovane, FJ AF Knowles, S Meier, RR Gustafson, BAS Giovane, FJ TI A search for small comets with the Naval Space Command radar SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID FAR-ULTRAVIOLET DAYGLOW; TRANSIENT DECREASES; ATMOSPHERIC HOLES; EARTH; UVI; HYPOTHESIS; TRAILS AB We have searched for the hypothetical small comets proposed by Frank et al. [1986a, b] and Frank and Sigwarth [1993] using the world's most powerful radar in terms of gain-aperture product. The Naval Space Surveillance System can detect most space objects in low Earth orbit with radar cross sections (RCSs) of 0.1 m(2) or larger; at higher altitudes of the order of 10,000-20,000 km the radar can detect objects with RCSs of 1 m(2). We carried out detailed first-principle calculations of the RCS of spherical comet using the properties proposed by Frank and Sigwarth [1993]. We find that 8-12 m diameter comets have an average cross section of 0.4 m(2) at the radar frequency (217 MHz), with peaks reaching 1 m Therefore the Naval radar system has sufficient sensitivity to detect many small comets, especially as they approach low Earth orbit. We estimate that at least 800-5000 small comets should have been detected by the radar during the 37 day search period during fall 1997. None of the more than 12,000 unidentified detections can be explained by small comets. The lack of detection of small comets by the radar can be explained only if small comets have RCSs <0.1% of their assumed physical size,(which is unrealistic, given that human technology can match this value only by tailoring a design for a specific radar) or if their impact rate with Earth is some 4 orders of magnitude less than proposed by Frank et al. [1986a] and Frank and Sigwarth [1993]. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Univ Florida, Dept Astron, Gainesville, FL 32611 USA. Raytheon Syst Co, Washington, DC USA. RP Knowles, S (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Code 7604, Washington, DC 20375 USA. RI Meier, Robert/G-4749-2014 OI Meier, Robert/0000-0001-8497-7115 NR 25 TC 7 Z9 7 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD JUN 1 PY 1999 VL 104 IS A6 BP 12637 EP 12643 DI 10.1029/1999JA900106 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 201MY UT WOS:000080600400035 ER PT J AU Gavrishchaka, VV Ganguli, SB Ganguli, GI AF Gavrishchaka, VV Ganguli, SB Ganguli, GI TI Electrostatic oscillations due to filamentary structures in the magnetic-field-aligned flow: The ion-acoustic branch SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID KINETIC ALFVEN WAVES; VELOCITY-SHEAR; POLAR CUSP; CYCLOTRON TURBULENCE; PLASMA TURBULENCE; AURORAL ARC; SOLAR-WIND; F-REGION; INSTABILITY; IONOSPHERE AB Recent space missions such as FAST and Freja report highly structured plasma hows along the magnetic field. Electrostatic fluctuations that can be supported by such inhomogeneous parallel hows are investigated. It is found that even a small transverse gradient in parallel flow can significantly reduce the critical value of the relative ion-electron field-aligned drift for the current-driven electrostatic ion acoustic modes. It is also shown that the shear-modified ion acoustic mode can be excited without any relative field-aligned drift provided that the flow gradient is sufficiently strong. The instability mechanism can be described in a local limit. The new shear-modified ion-acoustic modes considered in this paper are shown to be different from both the nonresonant mode due to a velocity shear in the parallel flow [D'Angelo, 1965] and the resonant classical current-driven ion-acoustic mode [Fried and Gould, 1961]. The new modes discussed in this paper can be excited for typical ionospheric conditions and a wide range of ion-electron temperature ratios. The reported results may explain ionospheric observations of low-frequency ion-acoustic-like waves, especially for ion-electron temperature ratios of the order of unity and larger when the critical current for the homogeneous current-driven ion acoustic mode is significantly above the observed values. Other possible applications of our results to space plasmas are also discussed. C1 Sci Applicat Int Corp, Mclean, VA 22102 USA. USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. RP Gavrishchaka, VV (reprint author), Sci Applicat Int Corp, Mclean, VA 22102 USA. NR 78 TC 47 Z9 47 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD JUN 1 PY 1999 VL 104 IS A6 BP 12683 EP 12693 DI 10.1029/1999JA900094 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 201MY UT WOS:000080600400039 ER PT J AU Frolov, VL Kagan, LM Sergeev, EN Komrakov, GP Bernhardt, PA Goldstein, JA Wagner, LS Selcher, CA Stubbe, P AF Frolov, VL Kagan, LM Sergeev, EN Komrakov, GP Bernhardt, PA Goldstein, JA Wagner, LS Selcher, CA Stubbe, P TI Ionospheric observations of F region artificial plasma turbulence, modified by powerful X-mode radio waves SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID STIMULATED ELECTROMAGNETIC EMISSION; HEATING EXPERIMENTS; UPPER HYBRID; IRREGULARITIES; INSTABILITIES; FREQUENCIES; CYCLOTRON; DECAY AB We study the influence of additional X-mode heating of the ionospheric plasma on the features of artificial ionospheric turbulence, induced in the ionospheric F region by O-mode waves over the "Sura" heating facility (Nizhny Novgorod, Russia). The X heating is shown to suppress the generation of HF plasma turbulence resulting from the development of both the parametric decay and thermal parametric instabilities. Typical times of variations in the turbulence intensity change from less than or equal to 0.1 s to similar to 10 s, strongly depending on the heating scheme. Aftereffects of the X heating last up to 30-60 s. We distinguish at least three types of phenomena, according to the observed typical times of the processes, and discuss possible reasons for each of them. C1 Radiophys Res Inst, Nizhnii Novgorod 603600, Russia. W Virginia Univ, Plasma Phys Lab, Morgantown, WV 26506 USA. USN, Res Lab, Washington, DC 20375 USA. Max Planck Inst Aeron, D-37191 Katlenburg Lindau, Germany. RP Frolov, VL (reprint author), Radiophys Res Inst, Nizhnii Novgorod 603600, Russia. NR 49 TC 10 Z9 11 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD JUN 1 PY 1999 VL 104 IS A6 BP 12695 EP 12704 DI 10.1029/1998JA900182 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 201MY UT WOS:000080600400040 ER PT J AU Osgood, RM Sinha, SK Freeland, JW Idzerda, YU Bader, SD AF Osgood, RM Sinha, SK Freeland, JW Idzerda, YU Bader, SD TI X-ray scattering from magnetically and structurally rough surfaces SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article; Proceedings Paper CT 3rd International Symposium on Metallic Multilayers (MML98) held Jointly with the EMRS Symposium on Magnetic Ultrathin Films and Ultrathin Film Nanostructures CY JUN 14-19, 1998 CL VANCOUVER, CANADA DE X-ray resonant magnetic scattering; surface roughness AB We present expressions for the resonant magnetic X-ray scattering (XRMS) by surfaces possessing roughness and analyze both the structural and magnetic roughness of a surface, as well as their correlation. We demonstrate that the leading contribution to the difference (Delta I) in the diffuse scattering between left- and right-circularly polarized light for a rough surface vanishes unless the structural and magnetic roughnesses are correlated, to leading order in the magnetization. The effects of magnetic domain structure and magnetic dead layers on the surface scattering are also discussed. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Expt Facilities Div, Argonne, IL 60439 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. 3M Corp, 3M Ctr, St Paul, MN 55144 USA. USN, Res Lab, Div Sci Mat, Washington, DC 20379 USA. RP Sinha, SK (reprint author), Argonne Natl Lab, Expt Facilities Div, 9700 S Cass Ave, Argonne, IL 60439 USA. EM sksinha@aps.anl.gov RI Bader, Samuel/A-2995-2013 NR 13 TC 34 Z9 34 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD JUN PY 1999 VL 198-99 BP 698 EP 702 DI 10.1016/S0304-8853(98)01098-1 PG 5 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 204TE UT WOS:000080779600219 ER PT J AU Holtz, RL Imam, MA AF Holtz, RL Imam, MA TI Hydrogen storage characteristics of ball-milled magnesium-nickel and magnesium-iron alloys SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID NI AB Of potential hydrogen storage materials, pure magnesium would be best from the standpoint of hydrogen capacity per unit mass. However, pure magnesium has poor hydriding kinetics. Alloying magnesium with nickel and other transition metals aids catalysis of the hydrogen dissociative chemisorption and yields other benefits by lowering the dehydrogenation temperature, although at the expense of decreased storage capacity. Magnesium-nickel alloys with about one percent nickel prepared by ball-milling yield the most significant improvements in hydrogen storage behavior relative to pure magnesium. (C) 1999 Kluwer Academic Publishers. C1 USN, Res Lab, Div Mat Sci & Technol, Washington, DC 20375 USA. RP Holtz, RL (reprint author), USN, Res Lab, Div Mat Sci & Technol, Code 6323, Washington, DC 20375 USA. NR 10 TC 30 Z9 30 U1 1 U2 6 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD JUN 1 PY 1999 VL 34 IS 11 BP 2655 EP 2663 DI 10.1023/A:1004617203266 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA 211VD UT WOS:000081181800023 ER PT J AU Nguyen, VQ Sanghera, JS Freitas, JA Aggarwal, ID Lloyd, IK AF Nguyen, VQ Sanghera, JS Freitas, JA Aggarwal, ID Lloyd, IK TI Structural investigation of chalcogenide and chalcohalide glasses using Raman spectroscopy SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article ID IR FIBER OPTICS; TELLURIUM AB HV- and HH-polarized Raman spectra of the chalcogenide glasses Ge30As10Se(60-x)Tex, (25 less than or equal to x less than or equal to 35) and the chalcohalide glasses Ge30As10Se30Te(30-y) I-y (0 less than or equal to y less than or equal to 30), Ge30As10Se35Te(25-z)Iz (0 less than or equal to z less than or equal to 20) were investigated. For the chalcogenide glasses, the main structural units include [AsSe3-xTex] mixed pyramidal units, [GeSe4-xTex] mixed tetrahedral units, and Ge-Te-Ge chains. The substitution of iodine for tellurium in the chalcohalide glasses results in the formation of Ge-I, As-I, and Se-I bonds which break up the three-dimensional network. The main structural units for the chalcohalide glasses are [AsSexTeyIz] mixed pyramidal units where x+y+z = 3, [GeSexTey I-z] mixed tetrahedral units where x + y + z = 4, and GeSe3/2I mixed tetrahedral units. The symmetry properties of these structural units has been determined through the dependence of the depolarization ratio on the frequency shift. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. RP Nguyen, VQ (reprint author), USN, Res Lab, Code 5606-1, Washington, DC 20375 USA. EM vnguyen@ccf.nrl.navy.mil RI Lloyd, Isabel/B-1513-2012 NR 23 TC 28 Z9 28 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 PY 1999 VL 248 IS 2-3 BP 103 EP 114 DI 10.1016/S0022-3093(99)00303-8 PG 12 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 211XC UT WOS:000081186300001 ER PT J AU Ngai, KL AF Ngai, KL TI Derivation of a relation between the activation energies of ionic conductivity in the glassy and molten states of glass-forming ionic conductors: an application to silver iodide-silver selenate SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article ID NON-ARRHENIUS CONDUCTIVITY; ELECTRICAL RELAXATION; MOBILE IONS; MELTS; EXPLANATION; DIFFUSION; SOLIDS AB In the glassy state of glass-forming ionic conductors, the temperature dependence of de conductivity a is Arrhenius with a constant activation energy, E-sigma,,. High above the glass transition temperature where a is approaching a level of 1 Omega(-1) cm(-1) and the corresponding conductivity relaxation times tau(sigma), are of the order of 1 ps, the apparent activation energy of sigma, E-a, is significantly smaller than E-sigma. In a previous study it Has shown that the ratio, E-a/E-sigma, is nearly equal to the fractional exponent. beta, of the Kohlrausch-Williams-Watts function, exp[-(t/tau(KWW))(beta)], which is a characteristic of the nonexponential conductivity relaxation of ionic conductors. In this work we show that this correlation between activation energies in the glassy and the molten states follows from results of the coupling model. Experimental data of C. Cramer and hi. Buscher have given conductivity relaxation?; spectra over a broad frequency range for a fast ion conducting 0.48(AgI)(2)-0.52Ag(2)SeO(4) composition below and above the glass transition temperature T-g We have analyzed the glassy state conductivity relaxation data by using the electric modulus formalism as well as by dh ect consideration of the ac conductivity. After the removal of a contribution to the ac conductivity that is proportional to omega(1.0). where omega is the angular frequency, the data in both representations are well fitted by the appropriate Fourier transform of Phi(t) = exp [-(t/tau(KWW))(beta)], With beta = 0.51. With this value of beta, we found that the product, beta E-sigma is about the same as E-a within experimental error, This agreement provides support for the correlation. E-a/E-sigma approximate to beta, which was previously established for glass-forming ionic conductors with decoupling indices, RI. that vary over t,twelve orders of magnitude, as well as for several crystalline ionic conductors. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. RP Ngai, KL (reprint author), USN, Res Lab, Code 6807,Bldg 208,Room 224, Washington, DC 20375 USA. NR 28 TC 17 Z9 17 U1 0 U2 3 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 1999 VL 248 IS 2-3 BP 194 EP 202 DI 10.1016/S0022-3093(99)00145-3 PG 9 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 211XC UT WOS:000081186300011 ER PT J AU Richardson, PE Arendt, DM Fidler, JE Webber, CM AF Richardson, PE Arendt, DM Fidler, JE Webber, CM TI Radiopaque mass in the submandibular region SO JOURNAL OF ORAL AND MAXILLOFACIAL SURGERY LA English DT Editorial Material ID PERIPHERAL OSTEOMA C1 USN, Ctr Med, Dept Oral & Maxillofacial Surg, Bethesda, MD 20889 USA. USN Hosp, Dept Oral & Maxillofacial Surg, Beaufort, SC USA. RP Fidler, JE (reprint author), USN, Ctr Med, Dept Oral & Maxillofacial Surg, 8901 Wisconsin Ave, Bethesda, MD 20889 USA. NR 20 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 USA SN 0278-2391 J9 J ORAL MAXIL SURG JI J. Oral Maxillofac. Surg. PD JUN PY 1999 VL 57 IS 6 BP 709 EP 713 DI 10.1016/S0278-2391(99)90439-1 PG 5 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 201YR UT WOS:000080625300021 PM 10368097 ER PT J AU Kelly, JR AF Kelly, JR TI Clinically relevant approach to failure testing of all-ceramic restorations SO JOURNAL OF PROSTHETIC DENTISTRY LA English DT Article; Proceedings Paper CT 80th Annual Meeting of the Academy-of-Prosthodontics CY MAY, 1998 CL COLORADO SPRINGS, CO SP Acad Prosthodont ID OCCLUSAL FORCES; DENTAL CERAMICS; BITE FORCE; COMPRESSIVE STRENGTH; ALUMINOUS PORCELAIN; CROWNS; WEAR; POPULATION; FREQUENCY; CONTACTS AB Statement of problem. One common test of single-unit restorations involves applying loads to clinically realistic specimens through spherical indenters, or equivalently, loading curved incisal edges against flat compression platens. As knowledge has become available regarding clinical failure mechanisms and the behavior of in vitro tests, it is possible to constructively question the clinical validity of such failure testing and to move toward developing more relevant test methods. Purpose. This article reviewed characteristics of the traditional load-to-failure test, contrasted these with characteristics of clinical failure for all-ceramic restorations, and sought to explain the discrepancies. Literature regarding intraoral conditions was reviewed to develop an understanding of how laboratory testing could be revised. Variables considered to be important in simulating clinical conditions were described, along with their recent laboratory evaluation. Conclusions. Traditional fracture tests of single unit all-ceramic prostheses are inappropriate, because they do not Create failure mechanisms seen in retrieved clinical specimens. Validated tests are needed to elucidate the role(s) that cement systems, bonding, occlusion, and even metal copings play in the success of fixed prostheses and to make meaningful comparisons possible among novel ceramic and metal substructures. Research over the past 6 years has shown that crack systems mimicking clinical failure can be produced in all-ceramic restorations under appropriate conditions. C1 NIST, Dent & Med Mat Grp, Gaithersburg, MD 20899 USA. USN, Sch Dent, Dent Res Inst, Bethesda, MD USA. RP Kelly, JR (reprint author), NIST, Dent & Med Mat Grp, 100 Bur Dr,Mail Stop 8545, Gaithersburg, MD 20899 USA. EM robert.kelly@nist.gov NR 62 TC 326 Z9 334 U1 0 U2 15 PU MOSBY-ELSEVIER PI NEW YORK PA 360 PARK AVENUE SOUTH, NEW YORK, NY 10010-1710 USA SN 0022-3913 EI 1097-6841 J9 J PROSTHET DENT JI J. Prosthet. Dent. PD JUN PY 1999 VL 81 IS 6 BP 652 EP 661 DI 10.1016/S0022-3913(99)70103-4 PG 10 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 207AF UT WOS:000080912600002 PM 10347352 ER PT J AU Walch, M Weiner, RM Colwell, RR Coon, SL AF Walch, M Weiner, RM Colwell, RR Coon, SL TI Use of L-DOPA and soluble bacterial products to improve set of Crassostrea virginica (Gmelin, 1791) and C. gigas (Thunberg, 1793) SO JOURNAL OF SHELLFISH RESEARCH LA English DT Article DE Crassostrea gigas; Crassostrea virginica; oyster set; set cues; bacteria; Shewanella colwelliana; L-DOPA; theophylline ID CASSIOPEA-ANDROMEDA CNIDARIA; SETTLEMENT BEHAVIOR; PACIFIC OYSTER; METAMORPHOSIS; LARVAE; INDUCTION; COLWELLIANA; SHEWANELLA; POLYCHAETA; SCYPHOZOA AB Solutions of L-dihydroxyphenylalanine (L-DOPA) and culture supernatants of the marine bacterium Shewanella colwelliana were used to treat competent Crassostrea larvae before transferring them to setting tanks. Setting trials were done in laboratory containers and on a larger scale in a Chesapeake Bay hatchery. Hatchery results showed a consistent and repeatable improvement in set of C. virginica after treatment with either L-DOPA or bacterial supernatants. Laboratory results were more variable, and differences between treatments were less pronounced. Pretreatment of larvae with theophylline led to a more rapid onset of settlement behavior in L-DOPA treatments but not in supernatant treatments, and had no clear effect on over-all set on cultch. C1 USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. Univ Maryland, Ctr Marine Biotechnol, MBI, Baltimore, MD 21202 USA. Univ Maryland, Dept Mol Genet & Cell Biol, College Pk, MD 20742 USA. Univ Maryland, Dept Biol, College Pk, MD 20742 USA. RP Walch, M (reprint author), USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. NR 32 TC 12 Z9 12 U1 1 U2 3 PU NATL SHELLFISHERIES ASSOC PI SOUTHAMPTON PA C/O DR. SANDRA E. SHUMWAY, NATURAL SCIENCE DIVISION, SOUTHAMPTON COLLEGE, SOUTHAMPTON, NY 11968 USA SN 0730-8000 J9 J SHELLFISH RES JI J. Shellfish Res. PD JUN PY 1999 VL 18 IS 1 BP 133 EP 138 PG 6 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 222YH UT WOS:000081812600019 ER PT J AU Kresin, VZ Ovchinnikov, YN Wolf, SA AF Kresin, VZ Ovchinnikov, YN Wolf, SA TI Layered superconductors in an external magnetic field SO JOURNAL OF SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT International Workshop on Exactly Aligned Magnetic Field Effects in Low-Dimensional Superconductors CY NOV 16-18, 1998 CL KYOTO, JAPAN DE layered superconductors; magnetic field ID CU-O; OXIDES AB Presence of localized magnetic moments and inhomogeneites leads to an unconventional behavior of the upper critical field for layered superconductors. In addition, one can observe a large diamagnetic moment at H tau N-c2 and in the normal resistive state. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. LD Landau Theoret Phys Inst, Moscow 11733V, Russia. USN, Res Lab, Washington, DC 20375 USA. RP Kresin, VZ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Wolf, Stuart/A-7513-2009 NR 19 TC 2 Z9 2 U1 0 U2 1 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0896-1107 J9 J SUPERCOND JI J. Supercond. PD JUN PY 1999 VL 12 IS 3 BP 493 EP 496 DI 10.1023/A:1007719831482 PG 4 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 215YX UT WOS:000081414000009 ER PT J AU Lingevitch, JF Collins, MD Siegmann, WL AF Lingevitch, JF Collins, MD Siegmann, WL TI Parabolic equations for gravity and acousto-gravity waves SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID SELF-STARTER; SOUND-SPEED; PROPAGATION; APPROXIMATIONS; REFLECTION; OCEAN; MEDIA AB Parabolic equations for gravity and acousto-gravity waves are derived and implemented. The wave equations for these problems contain singularities at depths at which the buoyancy frequency equals the forcing frequency. One of the advantages of the parabolic equation solution is that it is easy to avoid numerical problems associated with the singularities. Some problems involve an infinite number of propagating modes. This artifact of neglecting viscosity is handled by including stability constraints in the rational approximations used in the implementation of the parabolic equation. The parabolic equation is tested for idealized problems involving surface, internal, and interface gravity waves. Parabolic equation solutions are also presented for range-dependent problems involving internal waves in the ocean and acousto-gravity waves in the atmosphere. (C) 1999 Acoustical Society of America. [S0001-4966(99)04906-1]. C1 USN, Res Lab, Washington, DC 20375 USA. Rensselaer Polytech Inst, Troy, NY 12180 USA. RP Lingevitch, JF (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 26 TC 21 Z9 21 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JUN PY 1999 VL 105 IS 6 BP 3049 EP 3056 DI 10.1121/1.424634 PG 8 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 204RN UT WOS:000080778100006 ER PT J AU Miller, FR Neill, JW Sherfey, BW AF Miller, FR Neill, JW Sherfey, BW TI Implementation of a maximin power clustering criterion to select near replicates for regression lack-of-fit tests SO JOURNAL OF THE AMERICAN STATISTICAL ASSOCIATION LA English DT Article DE between clusters; lack of fit; minimal covers; nonreplication; regression; within clusters ID MODELS; DESIGNS AB In earlier work, we presented a maximin power clustering criterion to partition observations into groups of near replicates. Specifically, the criterion selects near replicate clusters for use with Christensen's tests for orthogonal between and within cluster lack of fit. This article further explores implementation of this clustering criterion. In particular, a methodology is developed to determine a collection of candidate groupings to which the maximin power criterion can be applied. C1 Kansas State Univ, Dept Math, Manhattan, KS 66506 USA. Kansas State Univ, Dept Stat, Manhattan, KS 66506 USA. USN, Air Warfare Ctr, Weap Div, China Lake, CA 93555 USA. RP Miller, FR (reprint author), Kansas State Univ, Dept Math, Manhattan, KS 66506 USA. NR 24 TC 7 Z9 7 U1 0 U2 0 PU AMER STATISTICAL ASSOC PI ALEXANDRIA PA 1429 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0162-1459 J9 J AM STAT ASSOC JI J. Am. Stat. Assoc. PD JUN PY 1999 VL 94 IS 446 BP 610 EP 620 DI 10.2307/2670181 PG 11 WC Statistics & Probability SC Mathematics GA 209QB UT WOS:000081058500030 ER PT J AU Kuo, HC Williams, RT Chen, JH AF Kuo, HC Williams, RT Chen, JH TI A possible mechanism for the eye rotation of Typhoon herb SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID VORTEX ROSSBY-WAVES; SPIRAL BANDS; AXISYMMETRIZATION; STABILITY; MODEL AB An elliptical eye that rotated cyclonically with a period of approximately 144 minutes in Typhoon Herb 1996 was documented. The elliptical region had a semimajor axis of 30 km and a semiminor axis of 20 km. Two complete periods of approximately 144 min were observed in the Doppler radar data. The rotation of the elliptical eye in the context of barotropic dynamics at three levels were explored: linear waves on a Rankin vortex, a nonlinear Kirchhoff vortex, and with a nonlinear spectral model. The linear wave theory involves the existence of both the high (potential) vorticity gradient near the eye edge and the cyclonic mean tangential Bow in the typhoon. The propagation of (potential) vorticity waves in the cyclonic mean flow makes the elliptical eye rotate cyclonically. The rotation period is longer than the period of a parcel trajectory moving in the cyclonic mean flow around the circumference, because the vorticity wave propagates upwind. The nonlinear theory stems from the rotation of Kirchhoff's vortex. Estimates of the eye rotation period from both linear and nonlinear theories agree with observations of the eye rotation period when the observed maximum wind from Herb is used. Nonlinear numerical computations suggest the importance of the interaction of neutral vorticity waves, which determine the shape and the rotation period of the eye. The calculations also support the rotation of the eye in approximately 144 min in the presence of axisymmetrization, vorticity redistribution, wave breaking, and vortex merging processes. C1 USN, Postgrad Sch, Dept Meteorol, MR,Wu,Jn, Monterey, CA 93943 USA. Natl Taiwan Univ, Dept Atmospher Sci, Taipei 10764, Taiwan. Cent Weather Bur, Taipei, Taiwan. RP Williams, RT (reprint author), USN, Postgrad Sch, Dept Meteorol, MR,Wu,Jn, Monterey, CA 93943 USA. OI KUO, HUNG-CHI/0000-0001-9102-5104 NR 20 TC 52 Z9 54 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD JUN 1 PY 1999 VL 56 IS 11 BP 1659 EP 1673 DI 10.1175/1520-0469(1999)056<1659:APMFTE>2.0.CO;2 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 204JY UT WOS:000080762200014 ER PT J AU Ni, N Chen, L Sun, F Wu, C AF Ni, N Chen, L Sun, F Wu, C TI Effect of heat transfer law on the performance of a generalized irreversible Carnot heat pump SO JOURNAL OF THE INSTITUTE OF ENERGY LA English DT Article ID OPTIMIZATION; CYCLES; COEFFICIENT; LOAD AB The sole ineversibility considered in an endoreversible Carnot heat pump model is the loss of heat resistance between the heat pump and its surrounding heat reservoirs. This paper presents a generalized irreversible Carnot heat pump model by taking into account several additional internal irreversibilities of the heat pump. such as heat leakage, friction, turbulence and other undesirable irreversibility factors. This is done by means of a constant parameter and a constant coefficient, together with the loss of heat resistance. The relationship between the optimal heating load and the coefficient of performance (COP) is derived from a generalized heat transfer law Q = K Delta(T-n). The effect of heat leakage, internal irreversibility, and heat transfer law on the optimal performance of the generalized irreversible Carnot heat pump is investigated. C1 Naval Acad Engn, Fac 306, Wuhan 430033, Peoples R China. RP Wu, C (reprint author), USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. NR 25 TC 19 Z9 22 U1 0 U2 0 PU INST ENERGY PI LONDON PA 18 DEVONSHIRE ST PORTLAND PLACE, LONDON, ENGLAND W1N 2AU SN 0144-2600 J9 J I ENERGY JI J. Inst. Energy PD JUN PY 1999 VL 72 IS 491 BP 64 EP 68 PG 5 WC Energy & Fuels SC Energy & Fuels GA 325TQ UT WOS:000087692800005 ER PT J AU Park, YS AF Park, YS TI Current status of group III-nitride semiconductors and future prospects SO JOURNAL OF THE KOREAN PHYSICAL SOCIETY LA English DT Article; Proceedings Paper CT 9th Seoul International Symposium on the Physics of Semiconductors and Applications (SEOUL ISPSA-98) CY NOV 06-07, 1998 CL KOREA UNIV, SEOUL, SOUTH KOREA HO KOREA UNIV ID GAN THIN-FILMS; CHEMICAL-VAPOR-DEPOSITION; N-TYPE GAN; SCHOTTKY-BARRIER DETECTORS; 2-DIMENSIONAL ELECTRON-GAS; CONTINUOUS-WAVE OPERATION; MULTIPLE-QUANTUM WELLS; LIGHT-EMITTING-DIODES; P-TYPE CONDUCTION; ALUMINUM NITRIDE AB During the past decade, group III-Nitride wide bandgap semiconductors have become the focus of extremely intensive research because of their exceptional physical properties and their high potential for use in countless numbers of applications. Nearly all aspects have been investigated, from the fundamental physical understanding of these materials to the development of the fabrication technology and demonstration of commercial devices. This purpose of this paper is to review the physical properties of III-Nitrides, their areas of application, the current status of the material technology including synthesis and processing. The state-of-the-art of III-Nitride material quality, as well as the devices which have been demonstrated, including electronic devices, ultraviolet photodetectors, visible light emitting diodes (LEDs) and ultraviolet-blue laser diodes, will also be presented. C1 Off Naval Res, Arlington, VA 22217 USA. RP Off Naval Res, 800 N Quincy St, Arlington, VA 22217 USA. NR 104 TC 25 Z9 25 U1 0 U2 5 PU KOREAN PHYSICAL SOC PI SEOUL PA 635-4, YUKSAM-DONG, KANGNAM-KU, SEOUL 135-703, SOUTH KOREA SN 0374-4884 EI 1976-8524 J9 J KOREAN PHYS SOC JI J. Korean Phys. Soc. PD JUN PY 1999 VL 34 SU S BP S199 EP S219 PG 21 WC Physics, Multidisciplinary SC Physics GA 214BE UT WOS:000081307100002 ER PT J AU Zeisse, CR McGrath, CP Littfin, KM Hughes, HG AF Zeisse, CR McGrath, CP Littfin, KM Hughes, HG TI Infrared radiance of the wind-ruffled sea SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION LA English DT Article; Proceedings Paper CT Advisory Group for Aerospace Research and Development Symposium on Remote Sensing - A Valuable Source of Information CY APR 22-25, 1996 CL TOULOUSE, FRANCE SP Advisory Grp Aerospace Res & Dev ID OCEAN; SURFACE; HORIZON AB The surface of the wind-ruffled sea contains capillary wave facets whose curvature is much larger than the wavelength of visible and infrared light. As a result, visible sea radiance consists of the sum of all the mirrorlike reflections of the sky and sun from each facet. In the infrared, additional radiance arises from blackbody emission by the facet and along the atmospheric path to the point of observation. Numerical calculations of mean sea radiance based on this model agree to within 1 degrees C with infrared data obtained in the long-wave band and in the short- and mid-wave bands outside the sun-glint corridor. If sun glint can be neglected, the spectral radiance of the ocean horizon is approximately given by the Planck function at the temperature of the ocean and lower atmosphere. (C) 1999 Optical Society of America [S0740-3232(99)01806-2] OCIS codes: 010.1290, 010.1300, 010.1310, 010.1320, 010.4450, 010.7340. C1 USN, Propagat Div, Space & Naval Warfare Syst Ctr, San Diego, CA 92152 USA. Sci & Technol Corp, Hampton, VA 23666 USA. RP Zeisse, CR (reprint author), USN, Propagat Div, Space & Naval Warfare Syst Ctr, 49170 Propagat Path, San Diego, CA 92152 USA. NR 28 TC 22 Z9 22 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3232 J9 J OPT SOC AM A JI J. Opt. Soc. Am. A-Opt. Image Sci. Vis. PD JUN PY 1999 VL 16 IS 6 BP 1439 EP 1452 DI 10.1364/JOSAA.16.001439 PG 14 WC Optics SC Optics GA 198YQ UT WOS:000080452500025 ER PT J AU Ring, DH Haines, GA Miller, DL AF Ring, DH Haines, GA Miller, DL TI Popliteal artery entrapment syndrome: Arteriographic findings and thrombolytic therapy SO JOURNAL OF VASCULAR AND INTERVENTIONAL RADIOLOGY LA English DT Article DE arteries, popliteal; popliteal artery, anatomy; popliteal artery, entrapment ID COMPUTED-TOMOGRAPHY; LOWER-EXTREMITY; EARLY DIAGNOSIS; DISEASE; COMPRESSION; ANGIOGRAPHY; MANAGEMENT; ANEURYSM AB PURPOSE: To review the arteriographic appearance of popliteal artery entrapment syndrome (PAES) and functional popliteal artery entrapment, and determine the role of thrombolysis in the treatment of these disorders. MATERIALS AND METHODS: Retrospective review of hospital records from 1991 to 1998, RESULTS: Seven patients with PAES and one with functional entrapment were identified. The popliteal artery was occluded in two limbs and compressed in 13, Active plantar flexion was necessary to demonstrate impingement in nine limbs. Medial deviation of the popliteal artery was evident in six of 14 patent popliteal arteries, and lateral deviation was observed in one limb. "Classic" abrupt medial angulation of the popliteal artery was observed in one limb. Both limbs were involved in all six patients who underwent bilateral popliteal exploration, Thrombolytic therapy was performed in three limbs. In two instances, it permitted a less extensive surgical procedure than would otherwise have been required. CONCLUSIONS: There is considerable variability in the arteriographic appearance of PAES, which is arteriographically indistinguishable from functional entrapment. It is frequently bilateral. Thrombolytic therapy does not obviate surgery but may permit a less extensive procedure to be performed. C1 USN, Med Res Inst, Dept Radiol, Bethesda, MD 20889 USA. Uniformed Serv Univ Hlth Sci, F Edward Hebert Sch Med, Dept Radiol & Nucl Med, Bethesda, MD 20814 USA. RP Miller, DL (reprint author), USN, Med Res Inst, Dept Radiol, 8901 Wisconsin Ave, Bethesda, MD 20889 USA. NR 41 TC 15 Z9 15 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1051-0443 J9 J VASC INTERV RADIOL JI J. Vasc. Interv. Radiol. PD JUN PY 1999 VL 10 IS 6 BP 713 EP 721 DI 10.1016/S1051-0443(99)70105-3 PG 9 WC Radiology, Nuclear Medicine & Medical Imaging; Peripheral Vascular Disease SC Radiology, Nuclear Medicine & Medical Imaging; Cardiovascular System & Cardiology GA 207PL UT WOS:000080945200004 PM 10392938 ER PT J AU VanCott, TC Mascola, JR Loomis-Price, LD Sinangil, F Zitomersky, N McNeil, J Robb, ML Birx, DL Barnett, S AF VanCott, TC Mascola, JR Loomis-Price, LD Sinangil, F Zitomersky, N McNeil, J Robb, ML Birx, DL Barnett, S TI Cross-subtype neutralizing antibodies induced in baboons by a subtype E gp120 immunogen based on an R5 primary human immunodeficiency virus type 1 envelope SO JOURNAL OF VIROLOGY LA English DT Article ID HUMAN MONOCLONAL-ANTIBODY; RECOMBINANT GP120; SOLUBLE CD4; HIV TYPE-1; OLIGOMERIC STRUCTURE; V3-SPECIFIC ANTIBODIES; GLYCOPROTEIN GP120; RECEPTOR-BINDING; EPITOPE EXPOSURE; MONOMERIC GP120 AB Global human immunodeficiency virus type 1 (HIV-1) diversity may require engineering vaccines to express antigens representing strains prevalent in the target population of vaccine testing. The majority (90%) of Incident infections in Thailand are genetic subtype E, with a small percentage of subtype B infections in the intravenous drug user populations. We have evaluated and compared the binding and HIV-1 neutralizing properties of serum antibodies induced in baboons by CHO cell-expressed monomeric gp120 derived from a CCR5-using (R5) subtype E primary HIV-1(CM235) or a CXCR4-using (X4) subtype B T-cell line-adapted (TCLA) HIV-1(SF2) isolate. In contrast to the subtype-specific HIV-1 neutralizing antibodies induced with recombinant HIV-1(SF2) gp120 (rgp120(SF2)), rgp120(CM235) immunization induced antibodies capable of neutralizing both subtype E and subtype B TCLA HIV-1 isolates. However, neither immunogen induced antibodies capable of neutralizing primary HIV-1 isolates. Antibody induced by rgp120(CM235) preferentially bound natively folded gp120 and retained strong cross-reactivity against multiple gp120 strains within subtype E as well as subtype B. In contrast, antibody responses to rgp120(SF2) were directed predominantly to linear epitopes poorly exposed on native gp120 and had more limited cross-recognition of divergent gp120, Fine epitope mapping revealed differences in antibody specificities. While both rgp120(CM235) and rgp120(SF2) induced antibodies to regions within C1, V1/V2, V3, and C5, unique responses were induced by rgp120(CM235) to multiple epitopes within C2 and by rgp120(SF2) to multiple epitopes within C3, V4, and C4. These data demonstrate that strain and/or phenotypic differences of HIV-1 subunit gp120 immunogens can substantially alter antibody binding specificities and subsequent HIV-1 neutralizing capacity. C1 Henry M Jackson Fdn, Rockville, MD 20850 USA. Walter Reed Army Inst Res, Div Retrovirol, Rockville, MD 20850 USA. USN, Med Res Inst, Dept Infect Dis, Bethesda, MD 20892 USA. Chiron Corp, Emeryville, CA 94608 USA. RP VanCott, TC (reprint author), Henry M Jackson Fdn, 13 Taft Ct,Suite 200, Rockville, MD 20850 USA. NR 88 TC 49 Z9 50 U1 0 U2 0 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0022-538X J9 J VIROL JI J. Virol. PD JUN PY 1999 VL 73 IS 6 BP 4640 EP 4650 PG 11 WC Virology SC Virology GA 195UW UT WOS:000080271400014 PM 10233923 ER PT J AU Leitmeyer, KC Vaughn, DW Watts, DM Salas, R de Chacon, IV Ramos, C Rico-Hesse, R AF Leitmeyer, KC Vaughn, DW Watts, DM Salas, R de Chacon, IV Ramos, C Rico-Hesse, R TI Dengue virus structural differences that correlate with pathogenesis SO JOURNAL OF VIROLOGY LA English DT Article ID TICK-BORNE ENCEPHALITIS; YELLOW-FEVER VIRUS; DIFFERENT DISEASE SEVERITIES; RNA SECONDARY STRUCTURES; AMINO-ACID-SEQUENCES; ENVELOPE PROTEIN-E; GENOME RNA; ANTIGENIC DETERMINANTS; MOLECULAR EVOLUTION; RESISTANT MUTANTS AB The understanding of dengue virus pathogenesis has been hampered by the lack of in vitro and in vivo models of disease. The study of viral factors involved in the production of severe dengue, dengue hemorrhagic fever (DHF), versus the more common dengue fever (DF), have been limited to indirect clinical and epidemiologic associations. In an effort to identify viral determinants of DHF, we have developed a method for comparing dengue type 2 genomes (reverse transcriptase PCR in six fragments) directly from patient plasma. Samples for comparison were selected from two previously described dengue type 2 genotypes which had been shown to be the cause of DF or DHF;. When full genome sequences of 11 dengue viruses were analyzed, several structural differences were seen consistently between those associated with DF only and those with the potential to cause DHF: a total of six encoded amino acid charge differences were seen in the prM, E, NS lb, and NS5 genes, while sequence differences observed within the 5' nontranslated region (NTR) and 3' NTR were predicted to change RNA secondary structures. We hypothesize that the primary determinants of DHF reside in (i) amino acid 390 of the E protein, which purportedly alters virion binding to host cells; (ii) in the downstream loop (nucleotides 68 to 80) of the 5' NTR,which may be involved in translation initiation; and (iii) in the upstream 300 nucleotides of the 3' NTR, which may regulate viral replication via the formation of replicative intermediates. The significance of four amino acid differences in the nonstructural proteins NS4b and NS5, a presumed transport protein and the viral RNA polymerase, respectively, remains unknown. This new approach to the study of dengue virus genome differences should better reflect the true composition of viral RNA populations in the natural host and permit their association with pathogenesis. C1 SW Fdn Biomed Res, Dept Virol & Immunol, San Antonio, TX 78245 USA. Walter Reed Army Inst Res, Dept Virus Res, Washington, DC 20307 USA. USN, Med Res Detachment, APO, AA 34032 USA. Minist Sanidad & Assistencia Social, Inst Nacl Higiene Rafael Rangel, Caracas, Venezuela. Hosp Cent Maracay, Serv Epidemiol, Maracay, Aragua, Venezuela. Inst Nacl Salud Publ, CISEI, Cuernavaca 62508, Morelos, Mexico. RP Rico-Hesse, R (reprint author), SW Fdn Biomed Res, Dept Virol & Immunol, POB 760549, San Antonio, TX 78245 USA. RI Rico-Hesse, Rebeca/C-5294-2011 OI Rico-Hesse, Rebeca/0000-0001-6216-1000 FU NIAID NIH HHS [AI01124, AI34533, P01 AI034533] NR 74 TC 367 Z9 397 U1 4 U2 48 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0022-538X J9 J VIROL JI J. Virol. PD JUN PY 1999 VL 73 IS 6 BP 4738 EP 4747 PG 10 WC Virology SC Virology GA 195UW UT WOS:000080271400025 PM 10233934 ER PT J AU Bajet, RV Kane, EJ Nunez, LA Dela Cruz, GR Barr, AL Breede, AM AF Bajet, RV Kane, EJ Nunez, LA Dela Cruz, GR Barr, AL Breede, AM TI Formation of the first US Navy Core Laboratory SO LABORATORY MEDICINE LA English DT Editorial Material C1 USN, Med Ctr, Core Lab, San Diego, CA 92152 USA. RP Bajet, RV (reprint author), USN, Med Ctr, Core Lab, San Diego, CA 92152 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC CLIN PATHOLOGISTS PI CHICAGO PA 2100 W HARRISON ST, CHICAGO, IL 60612 USA SN 0007-5027 J9 LAB MED JI Lab. Med. PD JUN PY 1999 VL 30 IS 6 BP 384 EP 388 PG 5 WC Medical Laboratory Technology SC Medical Laboratory Technology GA 201RZ UT WOS:000080610500010 ER PT J AU Hagen, RA Vogt, PR AF Hagen, RA Vogt, PR TI Seasonal variability of shallow biogenic gas in Chesapeake Bay SO MARINE GEOLOGY LA English DT Article DE acoustic turbidity; sediment gas bubbles; methane saturation; Chesapeake Bay ID SEDIMENTS; TEMPERATURE; METHANE; WATER; SEA AB Methane gas in Chesapeake Bay sediments occurs in buried paleodrainage channels incised during the last glacial sealevel lowstand. Repeat acoustic surveys of two Chesapeake Bay sites during the past year (with a 2-15 kHz chirp sonar profiler and 100 kHz sidescan sonar) show that the top of the zone of acoustically opaque bubbles in the sediments fluctuates vertically by up to 0.5 m, apparently in response to seasonal temperature changes. vertical movement of the gas layer is most apparent in the main channel of the bay, where the methane gas is very close to the seafloor. In areas where the gas is seen to be very near the seafloor on the chirp profiler records, the sidescan sonar data show corresponding high backscatter. This does not appear to be the result of differing sediment types. It is not likely that the sidescan signal is penetrating the seafloor at the shallow outer grazing angles of the sidescan swath, therefore, the gas must extend to the water-sediment interface. The areas of high backscatter caused by the gas are observed to change seasonally, expanding during the summer high-temperature period and shrinking during the winter low-temperature period. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Marine Phys Branch, Naval Res Lab, Washington, DC USA. RP Hagen, RA (reprint author), Seafloor Surveys Int Inc, 2727 Alaskan Way,Pier 69, Seattle, WA 98121 USA. NR 20 TC 29 Z9 30 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0025-3227 J9 MAR GEOL JI Mar. Geol. PD JUN PY 1999 VL 158 IS 1-4 BP 75 EP 88 DI 10.1016/S0025-3227(98)00185-6 PG 14 WC Geosciences, Multidisciplinary; Oceanography SC Geology; Oceanography GA 195GP UT WOS:000080242500005 ER PT J AU Rahman, A Bates, CW Marshall, AF Qadri, SB Bari, T AF Rahman, A Bates, CW Marshall, AF Qadri, SB Bari, T TI Microstructural and electronic transport properties of PtxSi/p-Si(100) metal-semiconductor composite films SO MATERIALS LETTERS LA English DT Article DE photodetectors; film; metal-semiconductor; Pt-Si; Schottky barrier ID OPTICAL-PROPERTIES; SENSOR AB Sputtered PtxSi/p-Si(100) films were characterized to assess their potential for applications in buried Schottky barrier devices. Transmission electron microscopy (TEM), X-ray diffraction and Hall measurements were used to measure structural and electronic transport properties and particle distribution. The findings presented in this paper provide insight into the potential device applications of these structures as photodetector devices operating in the 3-5 mu m range. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Howard Univ, Dept Elect Engn, Mat Sci Res Ctr Excellence, Washington, DC 20059 USA. Howard Univ, Dept Phys, Washington, DC 20059 USA. Stanford Univ, Ctr Mat Res, Stanford, CA 94305 USA. USN, Res Lab, Washington, DC 20375 USA. Howard Univ, Dept Chem, Washington, DC 20059 USA. RP Bates, CW (reprint author), Howard Univ, Dept Elect Engn, Mat Sci Res Ctr Excellence, Washington, DC 20059 USA. NR 10 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-577X J9 MATER LETT JI Mater. Lett. PD JUN PY 1999 VL 39 IS 6 BP 343 EP 349 DI 10.1016/S0167-577X(99)00032-4 PG 7 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 209JV UT WOS:000081045200007 ER PT J AU Walker, GJ Blood, CG AF Walker, GJ Blood, CG TI The patient flow of wounded marines within a multi-Echelon system of care SO MILITARY MEDICINE LA English DT Article AB Hospitalization data were extracted for Marines wounded in Vietnam from 1965 to 1969 to examine the echelon flow of treatment care for different types of injuries, The inter-echelon movement of each patient who was hospitalized at an echelon II or III facility was tracked until the treatment was completed or until the patient was moved to a facility in the continental United States. Results showed that approximately half of the admissions to echelon II or III facilities had no further treatment recorded at a higher echelon of care, Almost one-fourth of the patients required treatment at an echelon IV facility, and more than one-third were admitted to an echelon V facility. C1 Naval Hlth Res Ctr, Med Informat Syst & Operat Res Dept, San Diego, CA 92186 USA. RP Walker, GJ (reprint author), Naval Hlth Res Ctr, Med Informat Syst & Operat Res Dept, POB 85122, San Diego, CA 92186 USA. NR 9 TC 2 Z9 4 U1 0 U2 0 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD JUN PY 1999 VL 164 IS 6 BP 423 EP 427 PG 5 WC Medicine, General & Internal SC General & Internal Medicine GA 205UD UT WOS:000080838200010 PM 10377712 ER PT J AU Szymanski, CM Yao, RJ Ewing, CP Trust, TJ Guerry, P AF Szymanski, CM Yao, RJ Ewing, CP Trust, TJ Guerry, P TI Evidence for a system of general protein glycosylation in Campylobacter jejuni SO MOLECULAR MICROBIOLOGY LA English DT Article ID SURFACE-LAYER GLYCOPROTEIN; GUILLAIN-BARRE-SYNDROME; COLI VC167 FLAGELLIN; POSTTRANSLATIONAL MODIFICATION; MYCOBACTERIUM-TUBERCULOSIS; ALPHA-GLYCEROPHOSPHATE; ESCHERICHIA-COLI; IDENTIFICATION; LIPOPOLYSACCHARIDES; EXPRESSION AB A genetic locus from Campylobacter jejuni 81-176 (O:23, 36) has been characterized that appears to be involved in glycosylation of multiple proteins, including flagellin. The lipopolysaccharide (LPS) Gore of Escherichia coli DH5 alpha containing some of these genes is modified such that it becomes Immunoreactive with 0:23 and 0:36 antisera and loses reactivity with the lectin wheat germ agglutinin (WGA). She-specific mutation of one of these genes in the E. coli host causes loss of 0:23 and 0:36 antibody reactivity and restores reactivity with WGA. However, site-specific mutation of each of the seven genes in 81-176 failed to show any detectable changes in LPS. Multiple proteins from various cellular fractions of each mutant showed altered reactivity by Western blot analyses using 0:23 and 0:36 antisera. The changes in protein antigenicity could be restored in one of the mutants by the presence of the corresponding wild-type allele in trans on a shuttle vector. Flagellin, which is known to be a glycoprotein, was one of the proteins that showed altered reactivity with 0:23 and 0:36 antiserum in the mutants. Chemical deglycosylation of protein fractions from the 81-176 wild type suggests that the other proteins with altered antigenicity in the mutants are also glycosyrated. C1 USN, Med Res Ctr, Enter Dis Program, Rockville, MD USA. Univ Victoria, Dept Biochem & Microbiol, Victoria, BC, Canada. RP Szymanski, CM (reprint author), USN, Med Res Ctr, Enter Dis Program, Rockville, MD USA. EM guerryp@nmripo.nmri.nnmc.navy.mil RI Guerry, Patricia/A-8024-2011 NR 45 TC 240 Z9 245 U1 1 U2 14 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0950-382X EI 1365-2958 J9 MOL MICROBIOL JI Mol. Microbiol. PD JUN PY 1999 VL 32 IS 5 BP 1022 EP 1030 DI 10.1046/j.1365-2958.1999.01415.x PG 9 WC Biochemistry & Molecular Biology; Microbiology SC Biochemistry & Molecular Biology; Microbiology GA 209BK UT WOS:000081027300012 PM 10361304 ER PT J AU Skeen, MB Eggleston, M AF Skeen, MB Eggleston, M TI Thoraconeuralgia gravidarum SO MUSCLE & NERVE LA English DT Letter C1 USN, Med Ctr, Portsmouth, VA 23708 USA. RP Skeen, MB (reprint author), USN, Med Ctr, Portsmouth, VA 23708 USA. NR 2 TC 3 Z9 3 U1 0 U2 0 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0148-639X J9 MUSCLE NERVE JI Muscle Nerve PD JUN PY 1999 VL 22 IS 6 BP 779 EP 780 DI 10.1002/(SICI)1097-4598(199906)22:6<779::AID-MUS18>3.0.CO;2-1 PG 2 WC Clinical Neurology; Neurosciences SC Neurosciences & Neurology GA 202QC UT WOS:000080662800018 PM 10366235 ER PT J AU Kirk, AD Burkly, LC Batty, DS Baumgartner, RE Berning, JD Buchanan, K Fechner, JH Germond, RL Kampen, RL Patterson, NB Swanson, SJ Tadaki, DK TenHoor, CN White, L Knechtle, SJ Harlan, DM AF Kirk, AD Burkly, LC Batty, DS Baumgartner, RE Berning, JD Buchanan, K Fechner, JH Germond, RL Kampen, RL Patterson, NB Swanson, SJ Tadaki, DK TenHoor, CN White, L Knechtle, SJ Harlan, DM TI Treatment with humanized monoclonal antibody against CD154 prevents acute renal allograft rejection in nonhuman primates SO NATURE MEDICINE LA English DT Article ID CD40 LIGAND; ENDOTHELIAL-CELLS; T-CELLS; HELP; LYMPHOCYTES; ACTIVATION; TOLERANCE; SURVIVAL; GAMMA AB CD154 is the ligand for the receptor CD40. This ligand-receptor pair mediates endothelial and antigen-presenting cell activation, and facilitates the interaction of these cells with T cells and platelets. We demonstrate here that administration of a CD154-specific monoclonal antibody (hu5C8) allows for renal allotransplantation in outbred, MHC-mismatched rhesus monkeys without acute rejection. The effect persisted for more than 10 months after therapy termination, and no additional drug was required to achieve extended graft survival. Indeed, the use of tacrolimus or chronic steroids seemed to antagonize the anti-rejection effect. Monkeys treated with antibody against CD154 remained healthy during and after therapy. The mechanism of action does not require global depletion of T or B cells. Long-term survivors lost their mixed lymphocyte reactivity in a donor-specific manner, but still formed donor-specific antibody and generated T cells that infiltrated the grafted organ without any obvious effect on graft function. Thus, therapy with antibody against CD154 is a promising agent for clinical use in human allotransplantation. C1 USN, Med Res Ctr, Immune Cell Biol Program, Bethesda, MD 20889 USA. Univ Wisconsin, Sch Med, Div Transplantat, Madison, WI 53792 USA. Walter Reed Army Med Ctr, Organ Transplant Serv, Washington, DC 20307 USA. Biogen Inc, Cambridge Ctr 14, Cambridge, MA 02142 USA. RP Kirk, AD (reprint author), USN, Med Res Ctr, Immune Cell Biol Program, 8901 Wisconsin Ave, Bethesda, MD 20889 USA. RI Kirk, Allan/B-6905-2012; Fechner, John/C-5962-2016 OI Fechner, John/0000-0002-8220-7237 NR 23 TC 605 Z9 629 U1 0 U2 5 PU NATURE AMERICA INC PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1078-8956 J9 NAT MED JI Nat. Med. PD JUN PY 1999 VL 5 IS 6 BP 686 EP 693 DI 10.1038/9536 PG 10 WC Biochemistry & Molecular Biology; Cell Biology; Medicine, Research & Experimental SC Biochemistry & Molecular Biology; Cell Biology; Research & Experimental Medicine GA 205LR UT WOS:000080823300038 PM 10371508 ER PT J AU Lesher, S Spano, ML Mellen, NM Guan, L Dykstra, S Cohen, AH AF Lesher, S Spano, ML Mellen, NM Guan, L Dykstra, S Cohen, AH TI Stable lamprey swimming on a skeleton of unstable periodic orbits SO NEUROCOMPUTING LA English DT Article DE nonlinear; time series; phase synchronization; symbolic dynamics; coupled oscillators ID CHAOTIC TIME-SERIES; LOW-DIMENSIONAL DYNAMICS; PHASE SYNCHRONIZATION; SYMBOLIC DYNAMICS; NEURAL SYSTEMS; CARDIORESPIRATORY INTERACTION; NOISY SYSTEMS; NEURONS; DETERMINISM; OSCILLATORS AB We frame our use of nonlinear dynamic techniques historically, and show how evidence of phase synchronization between different lamprey motor roots is investigated using a mutual information measure. We also demonstrate a new approach for symbolically representing time series in terms of generic periodic points with an example. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Maryland, Dept Biol, College Pk, MD 20742 USA. USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. Univ Calif Los Angeles, Dept Physiol Sci, Los Angeles, CA 90024 USA. RP Univ Maryland, Dept Biol, College Pk, MD 20742 USA. RI Spano, Mark/B-6883-2011 NR 67 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0925-2312 EI 1872-8286 J9 NEUROCOMPUTING JI Neurocomputing PD JUN PY 1999 VL 26-7 BP 779 EP 788 DI 10.1016/S0925-2312(98)00147-7 PG 10 WC Computer Science, Artificial Intelligence SC Computer Science GA 216UK UT WOS:000081462700101 ER PT J AU Nuckols, ML AF Nuckols, ML TI Analytical modeling of a diver dry suit enhanced with micro-encapsulated phase change materials SO OCEAN ENGINEERING LA English DT Article DE diver dry suit modeling; micro-encapsulated phase change material (PCMs) AB Over the years, various forms of phase change materials (PCMs) have been utilized as thermal storage mediums for cooling and heating applications. Recently, the U.S. Navy has investigated using phase change materials inside divers' dry suits to enhance thermal protection in extremely cold water applications. The thermal performance of optional types of insulative Comfortemp(1) foam mediums, medium thicknesses, and foam-to-Thermosorb(2) ratios are evaluated analytically in this paper to compare the relative thermal performances of PCM-enhanced dry suits with existing commercial dry suits. An analytical model of dry suit systems, both conventional and those containing Comfortemp materials, is developed to predict their thermal performances in simulated ocean environments. This analytical model is used to compare the relative thermal performances of PCM-enhanced dry suits with existing commercial dry suits, and to assess the relative thermal performances of candidate Comfortemp foams, including those interspersed with different weight percentages of micro-encapsulated PCMs, in an effort to maximize thermal storage capabilities. The observations from this modeling effort provides guidelines and recommendations for materials selection and thickness requirements for candidate Comfortemp foams to be used in prototype dry suits for divers. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN Acad, Dept Naval Architecture Ocean & Marine Engn, Annapolis, MD 21402 USA. RP Nuckols, ML (reprint author), USN Acad, Dept Naval Architecture Ocean & Marine Engn, Annapolis, MD 21402 USA. NR 4 TC 37 Z9 42 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0029-8018 J9 OCEAN ENG JI Ocean Eng. PD JUN PY 1999 VL 26 IS 6 BP 547 EP 564 DI 10.1016/S0029-8018(98)00001-8 PG 18 WC Engineering, Marine; Engineering, Civil; Engineering, Ocean; Oceanography SC Engineering; Oceanography GA 137XD UT WOS:000076941600005 ER PT J AU Barton, O AF Barton, O TI Fundamental frequency of tapered plates by the method of eigensensitivity analysis SO OCEAN ENGINEERING LA English DT Article DE fundamental frequency; tapered plates; eigensensitivity analysis ID RECTANGULAR-PLATES; DISCONTINUOUS FASHION; TRANSVERSE VIBRATIONS; VARYING THICKNESS AB The fundamental frequency of a rectangular isotropic plate having a linear thickness variation is computed using the method of eigensensitivity analysis. The approach incorporates eigen derivatives to evaluate a Maclaurin series representation of the desired eigenvalue, here the fundamental frequency. Comparison with published results, for various taper ratios, aspect ratios, and support conditions, demonstrates the accuracy and utility of the expression and methodology. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. RP Barton, O (reprint author), USN Acad, Dept Mech Engn, Annapolis, MD 21402 USA. EM obarton@nadn.navy.mil NR 10 TC 5 Z9 5 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0029-8018 J9 OCEAN ENG JI Ocean Eng. PD JUN PY 1999 VL 26 IS 6 BP 565 EP 573 PG 9 WC Engineering, Marine; Engineering, Civil; Engineering, Ocean; Oceanography SC Engineering; Oceanography GA 137XD UT WOS:000076941600006 ER PT J AU Olbrechts, G Munters, T Clays, K Persoons, A Kim, OK Choi, LS AF Olbrechts, G Munters, T Clays, K Persoons, A Kim, OK Choi, LS TI High-frequency demodulation of multi-photon fluorescence in hyper-Rayleigh scattering SO OPTICAL MATERIALS LA English DT Article; Proceedings Paper CT Symposium M on Molecular Photonics for Optical Telecommunications - Materials, Physics and Device Technology of the 1998 E-MRS Spring Conference CY JUN 15-19, 1998 CL STRASBOURG, FRANCE SP European Mat Res Soc DE nonlinear optics (NLO); multi-photon fluorescence (MPF); two-photon fluorescence (2PF); hyper-rayleigh scattering (HRS); phasefluorimetry; demodulation ID ORDER HYPERPOLARIZABILITY; MOLECULES AB A technique has been established to determine the first hyperpolarizability value beta of fluorescent molecules based on femtosecond hyper-Rayleigh scattering (HRS). The intrinsic high harmonic content of the femtosecond pulse train is used as a high frequency amplitude modulation source. Due to the nonzero fluorescence lifetime, a high amplitude modulation frequency will result in an amplitude demodulated and phase shifted fluorescence signal. At very high modulation frequencies, the fluorescence signal becomes completely demodulated and only the inherent HRS signal will remain. A comparative study was made between the dispersion free beta(0)-value of a nonfluorescent ionic hemicyanine dye (DASPC(22)(+)) and the dispersion free beta(0)-value of the fluorescent inclusion complex of the dye incorporated in an amylose matrix. The fluorescence-free beta(0)-value for the complex appeared to be twice [(200 +/- 5) x 10(-30) esu] the beta(0)-value of the dye itself [(100 +/- 10) x 10(-30) esu]. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Louvain, Dept Chem, Ctr Res Mol Elect & Photon, Lab Chem & Biol Dynam, B-3001 Louvain, Belgium. USN, Res Lab, Div Chem, Washington, DC 20375 USA. Univ Arizona, Ctr Opt Sci, Tucson, AZ 85721 USA. RP Olbrechts, G (reprint author), Univ Louvain, Dept Chem, Ctr Res Mol Elect & Photon, Lab Chem & Biol Dynam, Celestijnenlaan 200D, B-3001 Louvain, Belgium. NR 12 TC 15 Z9 15 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0925-3467 J9 OPT MATER JI Opt. Mater. PD JUN PY 1999 VL 12 IS 2-3 BP 221 EP 224 DI 10.1016/S0925-3467(99)00060-9 PG 4 WC Materials Science, Multidisciplinary; Optics SC Materials Science; Optics GA 211BP UT WOS:000081140300008 ER PT J AU Hart, AKE Karakla, DW Pitman, KT Adams, JF AF Hart, AKE Karakla, DW Pitman, KT Adams, JF TI Oral and oropharyngeal squamous cell carcinoma in young adults: A report on 13 cases and review of the literature SO OTOLARYNGOLOGY-HEAD AND NECK SURGERY LA English DT Article; Proceedings Paper CT 101st Annual Meeting of the American-Academy-of-Otolaryngology-Head-and-Neck-Surgery CY SEP 07-10, 1997 CL SAN FRANCISCO, CALIFORNIA SP Amer Acad Otolaryngol Head & Neck Surg ID HUMAN PAPILLOMAVIRUS DNA; PHARYNGEAL CANCER; NECK-CANCER; HEAD; CAVITY; TONGUE; AGE AB OBJECTIVE: Squamous cell carcinoma (SCC) of the head and neck is rare in patients younger than 45 years, Patients aged 18 to 45 years with SCC of the oral cavity (OC) and oropharynx (OP) were retrospectively compared with older control subjects. METHODS: Twenty of 127 patients with OC/OP SCC were young adults. Thirteen patients (10 men) comprise the present series; 9 had OC lesions. Seven case controls were identified. RESULTS: Overall, 15,75% of patients with OC/OP SCC were 18 to 45 years old. Seven OC lesions were early stage, and 2 were late stage; OP lesions were evenly divided. Eleven of 13 patients were disease free at the time of their last visit; 2 died of disease. Thirty-one percent of young patients were heavy drinkers; 77% of them smoked. CONCLUSIONS: Young adults' survival rate resembles that reported for all patients with head and neck cancer stage for stage. Tobacco and alcohol abuse prevention among young people is imperative, Health care providers who encounter a young patient with a suspicious head or neck lesion must include malignancy in their differential diagnosis. C1 USN, Ctr Med, Dept Otolaryngol Head & Neck Surg, Portsmouth, VA 23708 USA. RP Hart, AKE (reprint author), USN, Ctr Med, Dept Otolaryngol Head & Neck Surg, 620 John Paul Jones Circle, Portsmouth, VA 23708 USA. NR 24 TC 28 Z9 30 U1 0 U2 1 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0194-5998 J9 OTOLARYNG HEAD NECK JI Otolaryngol. Head Neck Surg. PD JUN PY 1999 VL 120 IS 6 BP 828 EP 833 DI 10.1016/S0194-5998(99)70322-0 PG 6 WC Otorhinolaryngology; Surgery SC Otorhinolaryngology; Surgery GA 206DU UT WOS:000080862700009 PM 10352435 ER PT J AU Kuo, YK Schneider, CW Verebelyi, DT Nevitt, MV Skove, MJ Tessema, GX Li, H Pond, JM AF Kuo, YK Schneider, CW Verebelyi, DT Nevitt, MV Skove, MJ Tessema, GX Li, H Pond, JM TI The effect of Co substitution for Cu in Bi2Sr2Ca1Cu2O8-delta SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article DE metal-insulator transition; whiskers; pair-breaking ID NEUTRON-POWDER-DIFFRACTION; SINGLE-CRYSTALS; INSULATOR-TRANSITION; TRANSPORT-PROPERTIES; SUPERCONDUCTIVITY; TC; LOCALIZATION; TEMPERATURE; FILMS; NI AB We have grown single crystal whiskers of Bi-2(SrCa)(n+1)(Cu1-xCox)(n)O8-delta with 0 < x < 0.26, and measured their resistance R as a function of the temperature T. For x < 0.06, n = 2 in the majority of the sample and n = 3 in a small part. For both phases, the changes in T-c and in the extrapolated residual resistance due to Co substitution are the same for Co as it is for Zn and Ni, indicating that magnetic scattering is not important. For x approximate to 0.06, oxygenation can drive the sample from superconducting to insulating, indicating that both the scattering of the carriers and the number of carriers affect the superconducting-insulating transition. This occurs in samples in which the sheet resistance in a CuO plane is approximately h/(2e)(2). For x > 0.18, the samples are insulating and n = 1. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Clemson Univ, Dept Phys & Astron, Clemson, SC 29634 USA. Clemson Univ, Dept Chem, Clemson, SC 29634 USA. USN, Res Lab, Washington, DC 20375 USA. RP Clemson Univ, Dept Phys & Astron, Clemson, SC 29634 USA. NR 43 TC 9 Z9 9 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 EI 1873-2143 J9 PHYSICA C JI Physica C PD JUN 1 PY 1999 VL 319 IS 1-2 BP 1 EP 11 DI 10.1016/S0921-4534(99)00280-4 PG 11 WC Physics, Applied SC Physics GA 209TJ UT WOS:000081064700001 ER PT J AU Schwartz, IB Carr, TW AF Schwartz, IB Carr, TW TI Bi-instability as a precursor to global mixed-mode chaos SO PHYSICAL REVIEW E LA English DT Article ID INDUCED INTERMITTENCY; MODULATED PARAMETERS; LASER; BIFURCATION; CO2-LASER; SYSTEM; ATTRACTORS; DYNAMICS AB Bi-instability, in contrast to bistability, is shown to generate unstable chaotic saddles prior to the onset of chaos. The theory and numerics are applied to a CO2 laser model with modulated losses where unstable pairs of saddles coexist, form heteroclinic connections, and allow mixing between local chaotic attractors to produce global mixed-mode chaos. C1 USN, Res Lab, Special Project Nonlinear Sci, PPD, Washington, DC 20375 USA. So Methodist Univ, Dept Math, Dallas, TX 75275 USA. RP Schwartz, IB (reprint author), USN, Res Lab, Special Project Nonlinear Sci, PPD, Code 6700-3, Washington, DC 20375 USA. RI Schwartz, Ira/A-8073-2009 NR 22 TC 12 Z9 12 U1 0 U2 0 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 JUN PY 1999 VL 59 IS 6 BP 6658 EP 6661 DI 10.1103/PhysRevE.59.6658 PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 210YY UT WOS:000081134200056 PM 11969653 ER PT J AU Kohl, JG Singer, IL AF Kohl, JG Singer, IL TI Pull-off behavior of epoxy bonded to silicone duplex coatings SO PROGRESS IN ORGANIC COATINGS LA English DT Review DE pull-off behavior; silicone; duplex coatings ID ADHESION; STRENGTH; SOLIDS AB Flat-head studs, 7.2 mm diameter, were epoxied to 0.1-0.9 mm thick silicone layers attached to a rigid substrate. Pull-off tests were performed at nominally 1.5 N/s to establish critical pull-off forces and detachment modes at the epoxy-silicone interface. Most tests were performed on a two-layer coating consisting of a silicone top coat and a stiffer silicone bond coat. A few tests were performed with a single layer of transparent silicone on a glass substrate, which allowed video analysis of the interface during pull-off. Critical pull-off force, P-c, decreased as the thickness of the coated layers increased. The thickness dependence of P-c was shown to be in good agreement with a model presented by Kendall for pulling a rigid cylinder from a elastomeric glue layer, but modified to account for a two-layer elastomeric coating; P-c varied as t(1/2)*, where t* is an effective thickness, which depends on the bulk moduli of the coatings as well as their thicknesses. The observed pull-off mode was peeling, which occurred by nucleation, growth and coalescence of multiple voids initiated inside the contact area. (C) 1999 Elsevier Science S.A. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. RP Kohl, JG (reprint author), Chromalloy Dallas, Dallas, TX 75234 USA. RI Kohl, James /E-5365-2011 NR 11 TC 78 Z9 81 U1 6 U2 26 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 JUN PY 1999 VL 36 IS 1-2 BP 15 EP 20 DI 10.1016/S0300-9440(98)00074-5 PG 6 WC Chemistry, Applied; Materials Science, Coatings & Films SC Chemistry; Materials Science GA 222FP UT WOS:000081773400003 ER PT J AU Frantzich, S AF Frantzich, S TI Teaching through Tocqueville SO PS-POLITICAL SCIENCE & POLITICS LA English DT Article C1 USN Acad, Dept Polit Sci, Annapolis, MD 21402 USA. RP Frantzich, S (reprint author), USN Acad, Dept Polit Sci, Annapolis, MD 21402 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER POLITICAL SCIENCE ASSOC PI WASHINGTON PA 1527 NEW HAMPSHIRE N W, WASHINGTON, DC 20036 USA SN 1049-0965 J9 PS JI PS-Polit. Sci. Polit. PD JUN PY 1999 VL 32 IS 2 BP 203 EP 205 DI 10.2307/420549 PG 3 WC Political Science SC Government & Law GA 199RD UT WOS:000080494700007 ER PT J AU Grofman, B Owen, G Collet, C AF Grofman, B Owen, G Collet, C TI Rethinking the partisan effects of higher turnout: So what's the question? SO PUBLIC CHOICE LA English DT Article ID UNITED-STATES; VOTER TURNOUT; ELECTIONS; CLOSENESS; DEMOCRATS AB Controversy persists over the link between turnout and the likelihood of success of Democratic candidates (e.g., DeNardo, 1980, 1986; Zimmer, 1985; Tucker and Vedlitz, 1986; Piven and Cloward, 1988; Texeira, 1992; Radcliff, 1994, 1995; Erikson, 1995a, b). We argue that the authors in this debate have largely been talking past one another because of a failure to distinguish three quite different questions. The first question is: "Are low turnout voters more likely to vote Democratic than high turnout voters?'' The second question is: "Should we expect that elections in which turnout is higher are ones in which we can expect Democrats to have done better?'' The third question is the counterfactual: "If turnout were to have increased in some given election, would Democrats have done better?'' We show the logical independence of the first two questions from one another and from the third, and argue that previous researchers have failed to recognize this logical independence - sometimes thinking they were answering question three when in fact they were answering either question one or question two. Reviewing previous research, we find that the answer to the first question once was YES but, for more recent elections at the presidential level, now appears to be NO, while, for congressional and legislative elections, the answer to the second question appears generally to be NO. However, the third question is essentially unanswerable absent an explicit model of why and how turnout can be expected to increase, and/or analyses of individual level panel data. Thus, the cross-sectional and pooled data analyses of previous research are of almost no value in addressing this third question. C1 Univ Calif Irvine, Sch Social Sci, Irvine, CA 92697 USA. USN, Postgrad Sch, Dept Math, Monterey, CA 93943 USA. RP Grofman, B (reprint author), Univ Calif Irvine, Sch Social Sci, Irvine, CA 92697 USA. NR 39 TC 30 Z9 30 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0048-5829 J9 PUBLIC CHOICE JI Public Choice PD JUN PY 1999 VL 99 IS 3-4 BP 357 EP 376 DI 10.1023/A:1018397327176 PG 20 WC Economics; Political Science SC Business & Economics; Government & Law GA 198MT UT WOS:000080428500008 ER PT J AU Kovach, KA Cathcart, CE AF Kovach, KA Cathcart, CE TI Human Resource Information Systems (HRIS): Providing business with rapid data access, information exchange and strategic advantage SO PUBLIC PERSONNEL MANAGEMENT LA English DT Article AB This article will review the major components of a Human Resource Information System (HRIS), including systems that are computerized and those that are not. These basic components provide a foundation for the reader to understand and explore how computerized and non-computerized information can assist human resources (HR) professionals achieve certain human resource objectives. There are many different types of computer software available to help in developing a comprehensive human resource information system. There is no doubt that personal computers can support real human resource decisions, but the information must be available in a form that on be utilized effectively in the decision making process. C1 George Mason Univ, Sch Business Adm, Fairfax, VA 22030 USA. USN, Res & Engn Grp, Air Syst Team, Patuxent River, MD USA. RP Kovach, KA (reprint author), George Mason Univ, Sch Business Adm, 4400 Univ Dr, Fairfax, VA 22030 USA. NR 6 TC 21 Z9 21 U1 2 U2 6 PU INT PERSONNEL MANAGEMENT ASSN PI ALEXANDRIA PA 1617 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0091-0260 J9 PUBLIC PERS MANAGE JI Public Personnel Manage. PD SUM PY 1999 VL 28 IS 2 BP 275 EP 282 PG 8 WC Industrial Relations & Labor; Public Administration SC Business & Economics; Public Administration GA 212TL UT WOS:000081232500008 ER PT J AU Stewart, SG AF Stewart, SG TI Star formation triggering mechanisms revealed by far-ultraviolet, H alpha, and HI images of dwarf galaxies SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article C1 Univ Alabama, Dept Phys & Astron, Tuscaloosa, AL 35487 USA. RP Stewart, SG (reprint author), USN Observ, 3450 Massachusetts Ave NW, Washington, DC 20392 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0004-6280 J9 PUBL ASTRON SOC PAC JI Publ. Astron. Soc. Pac. PD JUN PY 1999 VL 111 IS 760 BP 773 EP 773 DI 10.1086/316379 PG 1 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 207ZM UT WOS:000080965700014 ER PT J AU Hong, XD Raman, S Hodur, RM Xu, L AF Hong, XD Raman, S Hodur, RM Xu, L TI The mutual response of the tropical squall line and the ocean SO PURE AND APPLIED GEOPHYSICS LA English DT Article DE COAMPS; coupled model; mutual response; tropical squall line; atmosphere; ocean; heat fluxes ID MESOSCALE CONVECTIVE SYSTEM; TOGA-COARE; EVOLUTION; PRECIPITATION; MODEL; SURFACE; PARAMETERIZATION; ORGANIZATION; SIMULATION; DYNAMICS AB The Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS) is used to investigate the mutual response of a tropical squall line and the ocean. Simulated squall line compares well with the observations, and consists of counterrotating vortices, and has a bow shape bulge toward the leading edge. In addition to these features, which are also shown in the:he previous numerical simulations, the unique results from the coupled simulation indicate that the:he air-sea interaction processes within the squall line are important. They affect both the atmosphere and the ocean locally. Simulated upper ocean displays significant response to the squall line with upwelling and baroclinicity. Depth of the ocean mixed layer in the coupled simulation becomes modified due to feedback processes. Ocean temperature acts as a destabilizing factor, and the salinity as a stabilizing factor. Surface turbulent fluxes from the coupled simulation are about 10% less than that of the uncoupled simulation. The SST in the coupled simulation decreases by about 0.21 degrees C. Predicted squall line in the coupled simulation is weaker as compared to the uncoupled simulation. This is reflected in terms of differences in surface fluxes, cloud water, rain water and vertical velocities between the two simulations. C1 USN, Res Lab, Univ Corp Atmospher Res, Monterey, CA 93943 USA. N Carolina State Univ, Dept Marine Earth & Atmospher Sci, Raleigh, NC 27695 USA. USN, Res Lab, Sci Applicat Int Corp, Monterey, CA 93943 USA. RP Hong, XD (reprint author), USN, Res Lab, Univ Corp Atmospher Res, Monterey, CA 93943 USA. NR 32 TC 2 Z9 2 U1 0 U2 0 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 1999 VL 155 IS 1 BP 1 EP 32 DI 10.1007/s000240050252 PG 32 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 216VN UT WOS:000081465300001 ER PT J AU Malek-Madani, R Raouf, RA AF Malek-Madani, R Raouf, RA TI Stability analysis of thermo-visco-plastic materials undergoing high-rate shear deformations SO QUARTERLY OF APPLIED MATHEMATICS LA English DT Article AB In this paper we present an energy estimate for two systems of partial differential equations that govern thermo-mechanical. behavior of materials undergoing simple and anti-plane shear deformations. A linearized stability analysis is then carried out for the case of simple shear deformation with an exponentially softening stress-strain law. A series of numerical experiments on the fully nonlinear one-dimensional system of partial differential equations constitutes the final section of the paper. C1 USN Acad, Dept Math, Annapolis, MD 21402 USA. USN Acad, Dept Engn Mech, Annapolis, MD 21402 USA. RP Malek-Madani, R (reprint author), USN Acad, Dept Math, Annapolis, MD 21402 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER MATHEMATICAL SOC PI PROVIDENCE PA 201 CHARLES ST, PROVIDENCE, RI 02940-2213 USA SN 0033-569X J9 Q APPL MATH JI Q. Appl. Math. PD JUN PY 1999 VL 57 IS 2 BP 213 EP 227 PG 15 WC Mathematics, Applied SC Mathematics GA 194FT UT WOS:000080182000002 ER PT J AU Tylka, AJ Dietrich, WF AF Tylka, AJ Dietrich, WF TI IMP-8 observations of the spectra, composition, and variability of solar heavy ions at high energies relevant to manned space missions SO RADIATION MEASUREMENTS LA English DT Article; Proceedings Paper CT Workshop on Impact of Solar Energetic Particle Events for the Design of Human Space Missions CY SEP 09-11, 1997 CL CTR ADV SPACE STUDIES, HOUSTON, TEXAS HO CTR ADV SPACE STUDIES DE solar energetic particles; solar flares; ionizing radiation; manned space flight; coronal mass ejections ID CHARGE-STATE MEASUREMENTS; EJECTION-DRIVEN SHOCKS; SINGLE-EVENT UPSETS; ENERGETIC PARTICLES; IN-SPACE; ACCELERATION; ABUNDANCES; FLARES; MODEL; NUCLEON AB In more than 25 years of almost continuous observations, the University of Chicago's Cosmic Ray Telescope (CRT) on IMP-8 has amassed a unique database on high-energy solar heavy ions of potential relevance to manned spaceflight. In the very largest particle events, IMP-8/CRT has even observed solar Fe ions above the Galactic cosmic ray background up to similar to 800 MeV/nucleon, an energy sufficiently high to penetrate nearly 25 g/cm(2) of shielding. IMP-8/CRT observations show that high-energy heavy-ion spectra are often surprisingly hard power laws, without the exponential roll-offs suggested by stochastic acceleration fits to lower energy measurements alone. Also, in many solar particle events the Fe/O ratio grows with increasing energy, contrary to the notion that ions with higher mass-to-charge ratios should be less abundant at higher energies. Previous studies of radiation hazards for manned spaceflight have often assumed heavy-ion composition and steeply-falling energy spectra inconsistent with these observations. Conclusions based on such studies should therefore be re-assessed. The significant event-to-event variability observed in the high-energy solar heavy ions also has important implications for strategies in building probabilistic models of solar particle radiation hazards. Published by Elsevier Science Ltd. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Univ Chicago, Lab Astrophys & Space Res, Enrico Fermi Inst, Chicago, IL 60637 USA. RP Tylka, AJ (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Code 7654, Washington, DC 20375 USA. RI Tylka, Allan/G-9592-2014 FU NCCDPHP CDC HHS [DPR W-19493] NR 55 TC 20 Z9 20 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1350-4487 J9 RADIAT MEAS JI Radiat. Meas. PD JUN PY 1999 VL 30 IS 3 BP 345 EP 359 DI 10.1016/S1350-4487(99)00062-1 PG 15 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 255LU UT WOS:000083671000015 PM 11543141 ER PT J AU Warrenfeltz, L McCarren, D AF Warrenfeltz, L McCarren, D TI Naval Oceanographic Office Ocean Survey 2010 SO SEA TECHNOLOGY LA English DT Article C1 USN, Oceanog Off, Integrat & Technol Dept, Stennis Space Ctr, MS 39529 USA. RP Warrenfeltz, L (reprint author), USN, Oceanog Off, Integrat & Technol Dept, Stennis Space Ctr, MS 39529 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU COMPASS PUBL INC PI ARLINGTON PA SUITE 1000 1117 N 19 ST, ARLINGTON, VA 22209 USA SN 0093-3651 J9 SEA TECHNOL JI Sea Technol. PD JUN PY 1999 VL 40 IS 6 BP 61 EP 64 PG 4 WC Engineering, Ocean SC Engineering GA 210KW UT WOS:000081105300009 ER PT J AU Salas, E Rozell, D Mullen, B Driskell, JE AF Salas, E Rozell, D Mullen, B Driskell, JE TI The effect of team building on performance - An integration SO SMALL GROUP RESEARCH LA English DT Article ID GROUP COHESIVENESS; METAANALYSIS; SALIENCE; WORK; CONFIRMATION AB In this article, meta-analytic integration of research examining the effects of team building on performance is reported. Overall, there was no significant effect of team building on performance. However the effects of team building varied as a function of the type of operationalization of performance: On objective measures of performance, there was a nonsignificant tendency for team building to decrease performance, whereas on subjective measures of performance, there was a significant albeit small, tendency for ream building to increase performance. Examination of the specific components of team building revealed that interventions emphasizing role clarification were more likely to increase performance, whereas interventions that emphasized goal setting, problem solving, or interpersonal relations were no more likely to render an increase or decrease in performance. Finally the effects of ream building decreased as a function of the size of the team. The discussion considers implications of these effects of team building on performance. C1 USN, Air Warfare Ctr, Training Syst Div, Orlando, FL 32826 USA. Syracuse Univ, Syracuse, NY 13244 USA. RP Salas, E (reprint author), USN, Air Warfare Ctr, Training Syst Div, Code 4961,12350 Res Pkwy, Orlando, FL 32826 USA. NR 53 TC 75 Z9 75 U1 2 U2 23 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 USA SN 1046-4964 J9 SMALL GR RES JI Small Group Res. PD JUN PY 1999 VL 30 IS 3 BP 309 EP 329 DI 10.1177/104649649903000303 PG 21 WC Psychology, Applied; Management; Psychology, Social SC Psychology; Business & Economics GA 202ED UT WOS:000080638400003 ER PT J AU Cliver, EW Webb, DF Howard, RA AF Cliver, EW Webb, DF Howard, RA TI On the origin of solar metric type II bursts SO SOLAR PHYSICS LA English DT Review ID CORONAL MASS EJECTIONS; RADIO-BURSTS; INTERPLANETARY SHOCKS; PARTICLE-ACCELERATION; SMM OBSERVATIONS; PROTON FLARES; EMISSION; TRANSIENTS; EVENTS; ASSOCIATIONS AB The vast majority of solar flares are not associated with metric Type II radio bursts. For example, for the period February 1980-July 1982, corresponding to the first two and one-half years of the Solar Maximum Mission, 95% of the similar to 2500 flares with peak > 25 keV count rates > 100 c s(-1) lacked associated Type II emission. Even the similar to 360 largest flares, i.e., those having > 25 keV peak count rates > 1000 c s(-)1, had a Type II association rate of only 24%. The lack of a close correlation between flare size and Type II occurrence implies the need for a 'special condition' that distinguishes flares that are accompanied by metric Type II radio bursts from those of comparable size that are not. The leading candidates for this special condition are: (1) an unusually low Alfven speed in the flaring region; and (2) fast material motion. We present evidence based on SMM and GOES X-ray data and Solwind coronagraph data that argues against the first of these hypotheses and supports the second. Type II bursts linked to flares within 30 degrees of the solar limb are well associated (64%; 49/76) with fast (> 400 km s(-1)) coronal mass ejections (CMEs); for Type II flares within 15 degrees of the limb, the association rate is 79% (30/38). An examination of the characteristics of 'non-CME' flares associated with Type IIs does not support the flare-initiated blast wave picture that has been proposed for these events and suggests instead that CMEs may have escaped detection. While the degree of Type II-CME association increases with flare size, there are notable cases of small Type II flares whose outstanding attribute is a fast CME. Thus we argue that metric Type II bursts (as well as the Moreton waves and kilometric Type II bursts that may accompany them) have their root cause in fast coronal mass ejections. C1 USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. Boston Coll, Inst Sci Res, Chestnut Hill, MA 02167 USA. USN, EO Hulburt Ctr Space Res, Res Lab, Washington, DC 20375 USA. RP USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. EM cliver@plh.af.mil; webb@plh.af.mil; howard@maple.nrl.navy.mil NR 109 TC 165 Z9 169 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-0938 EI 1573-093X J9 SOL PHYS JI Sol. Phys. PD JUN PY 1999 VL 187 IS 1 BP 89 EP 114 DI 10.1023/A:1005115119661 PG 26 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 235GX UT WOS:000082534900008 ER PT J AU Enad, JG AF Enad, JG TI Patellar tendon ruptures SO SOUTHERN MEDICAL JOURNAL LA English DT Article ID REPAIR; KNEE AB Background. Isolated rupture of the patellar tendon is a rare injury. Often occurring during a fall in 20- and 30-year olds, patients may have a preexisting medical condition leg, history of steroid use) or a history of repetitive microtrauma to the knee. A high-riding, patella on physical examination and radiographs is pathognomonic. Methods. Immediate orthopaedic referral for surgical repair is necessary to reestablish knee extension. Delay in diagnosis can make surgical treatment more difficult. Current methods of postoperative rehabilitation are evolving. Results. Evaluative studies based on rating scales show satisfactory clinical and functional results after surgery. However, time lost from work and recreation may be protracted, and quadriceps atrophy is often evident. Conclusions. Ruptures of the patellar tendon should be diagnosed acutely and immediately referred to an orthopaedic surgeon. The impact of the injury to the patient may be longstanding even after operative treatment. Contemporary surgical and rehabilitative techniques give the best opportunity for restoration of functional activity. C1 USN, Med Ctr, Dept Orthopaed Surg, Portsmouth, VA 23708 USA. RP Enad, JG (reprint author), USN, Med Ctr, Dept Orthopaed Surg, 620 John Paul Jones Circle, Portsmouth, VA 23708 USA. NR 18 TC 13 Z9 17 U1 0 U2 2 PU SOUTHERN MEDICAL ASSN PI BIRMINGHAM PA 35 LAKESHORE DR PO BOX 190088, BIRMINGHAM, AL 35219 USA SN 0038-4348 J9 SOUTHERN MED J JI South.Med.J. PD JUN PY 1999 VL 92 IS 6 BP 563 EP 566 PG 4 WC Medicine, General & Internal SC General & Internal Medicine GA 205NR UT WOS:000080827900003 PM 10372848 ER PT J AU DeGraba, TJ Hallenbeck, JM Pettigrew, KD Dutka, AJ Kelly, BJ AF DeGraba, TJ Hallenbeck, JM Pettigrew, KD Dutka, AJ Kelly, BJ TI Progression in acute stroke - Value of the initial NIH Stroke Scale score on patient stratification in future trials SO STROKE LA English DT Article DE outcome; stroke assessment; stroke, acute ID ACUTE ISCHEMIC STROKE; SYSTEM CEREBRAL INFARCTION; PROFILE CLINICAL COURSE; SPONTANEOUS IMPROVEMENT; PROGNOSIS; SERIAL AB Background and Purpose-The objective was to determine the occurrence of neurological changes during the first 48 hours after acute stroke as it relates to initial stroke severity, Methods The National Institutes of Health Stroke Scale (NIHSS) was performed serially for the first 48 hours on 127 consecutive ischemic stroke patients (129 strokes) admitted to the neuroscience intensive care unit. Incidence of stroke progression (a greater than or equal to 3-point increase on the NIHSS) was recorded and analysis performed to determine its association with initial stroke severity and other demographic and physiological variables, Deficit resolution by 48 hours, defined as an NIHSS score of 0 or 1, measured the frequency of functional recovery predicted by the initial deficit, Results-Overall progression was noted in 31% of events (40/129). Applying Bayes' solution to the observed frequency of worsening, the greatest likelihood of predicting future patient progression occurs with stratification at NIHSS scores of less than or equal to 7 and >7. Patients with an initial NIHSS of less than or equal to 7 experienced a 14.8% (13/88) worsening rate versus a those with a score of >7 with a 65.9% (27/41) worsening rate (P<0.000005). Forty-five percent (40/88) of those with an initial score of less than or equal to 7 were functionally normal at 48 hours, whereas only 2.4% (1/41) of those with scores of >7 returned to a normal examination within this period (chi(2), P<0.000005). Conclusions-This study suggests that the early clinical course of the neurological deficit after acute stroke is dependent on the initial stroke severity and that a dichotomy in early outcome exists surrounding an initial NIHSS score of 7. These findings may have significant implications for the design and patient stratification in treatment protocols with respect to primary clinical outcome. C1 NINDS, Clin Stroke Res Unit, Stroke Branch, NIH, Bethesda, MD 20892 USA. USN, Med Ctr, Dept Neurol, Bethesda, MD 20814 USA. NIMH, NIH, Bethesda, MD 20892 USA. Natl Naval Med Ctr, Dept Crit Care Med, Bethesda, MD USA. RP DeGraba, TJ (reprint author), NINDS, Clin Stroke Res Unit, Stroke Branch, NIH, 36 Convent Dr MSC 4128,Bldg 36 Rm 4A-03, Bethesda, MD 20892 USA. NR 24 TC 140 Z9 150 U1 0 U2 2 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0039-2499 J9 STROKE JI Stroke PD JUN PY 1999 VL 30 IS 6 BP 1208 EP 1212 PG 5 WC Clinical Neurology; Peripheral Vascular Disease SC Neurosciences & Neurology; Cardiovascular System & Cardiology GA 201CX UT WOS:000080578100009 PM 10356101 ER PT J AU Johnson, WB Lall, R Bongar, B Nordlund, MD AF Johnson, WB Lall, R Bongar, B Nordlund, MD TI The role of objective personality inventories in suicide risk assessment: An evaluation and proposal SO SUICIDE AND LIFE-THREATENING BEHAVIOR LA English DT Article ID SELF-REPORT; IDEATION; PATIENT; MCMI; BEHAVIOR; MMPI; PSYCHIATRISTS; PSYCHOTICISM; STANDARDS; STUDENTS AB Objective personality assessment instruments offer a comparatively underutilized source of clinical data in attempts to evaluate and predict risk, for suicide. In contrast to focal suicide risk measures, global personality inventories may be useful in identification of long-standing styles that predispose persons to eventual suicidal behavior This article reviews the empirical literature regarding the efficacy of established personality inventories in predicting suicidality. The authors offer several recommendations for future research with these measures and conclude that such objective personality instruments offer only marginal utility as sources of clinical information in comprehensive suicide risk evaluations. Personality inventories may offer greatest utility in long-term assessment of suicide risk. C1 USN Acad, Dept Leadership Eth & Law, Annapolis, MD 21402 USA. Stanford Univ, Sch Med, Dept Psychiat, Palo Alto, CA 94304 USA. Clackamas Cty Mental Hlth, Clackamas, OR USA. Pacific Grad Sch Psychol, Palo Alto, CA USA. RP Johnson, WB (reprint author), USN Acad, Dept Leadership Eth & Law, Luce Hall,Stop 7B,112 Cooper Rd, Annapolis, MD 21402 USA. NR 99 TC 12 Z9 12 U1 1 U2 2 PU GUILFORD PUBLICATIONS INC PI NEW YORK PA 72 SPRING STREET, NEW YORK, NY 10012 USA SN 0363-0234 J9 SUICIDE LIFE-THREAT JI Suicide Life-Threat. Behav. PD SUM PY 1999 VL 29 IS 2 BP 165 EP 185 PG 21 WC Psychiatry; Psychology, Multidisciplinary SC Psychiatry; Psychology GA 212DY UT WOS:000081202700008 PM 10407969 ER PT J AU Chavko, M Braisted, JC Harabin, AL AF Chavko, M Braisted, JC Harabin, AL TI Attenuation of brain hyperbaric oxygen toxicity by fasting is not related to ketosis SO UNDERSEA & HYPERBARIC MEDICINE LA English DT Article DE starvation; ketosis; convulsions; central nervous system oxygen toxicity; glucose; brain ID NITRIC-OXIDE; ELECTRICAL-ACTIVITY; FOOD-DEPRIVATION; RAT; METABOLISM; GLUCOSE; 1,3-BUTANEDIOL; STARVATION; SEIZURES AB The effect of 24 h of fasting and changes in blood glucose and beta-hydroxybutyrate (BHB) level on latency to seizures in hyperbaric oxygen (HBO2) was studied. Conscious, unrestrained rats implanted with cortical electroencephalogram electrodes were exposed to 0.5 MPa (gauge pressure) O-2 until seizures were observed. Fasting for 24 h significantly (P <0.01) decreased blood glucose (from 8.6 +/- 0.9 in fed to 6.9 +/- 0.7 mM in the fasted group), increased blood BHB (0.07 +/- 0.02 mM to 0.38 +/- 0.10 mM, respectively), and prolonged the latency to seizures compared with normally fed animals (21.0 +/- 9.8 vs. 34.6 +/- 17.7 min, P < 0.05). Injection of the ketone precursor 1,3-butanediol (BD) to the fed animals increased blood BHB level to 0.72 +/- 0.32; however, seizure latency remained the same as in fed animals. Restoration of blood glucose in fasted animals to the same level as in the fed group did not reverse the protection achieved by fast; instead it increased the latency to seizures. The results indicate that the protection against HBO2 seizures by fasting in shed starvation is not related to the increase in circulating ketone bodies or decrease in blood glucose. C1 USN, Med Res Ctr, Bethesda, MD 20889 USA. RP Chavko, M (reprint author), USN, Med Res Ctr, 8901 Wisconsin Ave, Bethesda, MD 20889 USA. NR 32 TC 5 Z9 7 U1 0 U2 1 PU UNDERSEA & HYPERBARIC MEDICAL SOC INC PI KENSINGTON PA 10531 METROPOLITAN AVE, KENSINGTON, MD 20895 USA SN 1066-2936 J9 UNDERSEA HYPERBAR M JI Undersea Hyperb. Med. PD SUM PY 1999 VL 26 IS 2 BP 99 EP 103 PG 5 WC Marine & Freshwater Biology; Medicine, Research & Experimental SC Marine & Freshwater Biology; Research & Experimental Medicine GA 204LY UT WOS:000080766800007 PM 10372429 ER PT J AU DeLoach, JJ Null, C Fiore, S Konkol, P AF DeLoach, JJ Null, C Fiore, S Konkol, P TI The right welding wire could help the US Navy save millions SO WELDING JOURNAL LA English DT Article C1 USN, Ctr Surface Weap, Silver Spring, MD 20910 USA. USN, Sea Syst Command, Washington, DC USA. Concurrent Technol Corp, Johnstown, PA USA. RP DeLoach, JJ (reprint author), USN, Ctr Surface Weap, Silver Spring, MD 20910 USA. RI Demenkov, Valentin/B-4755-2014; Panzhin, Andrey/E-5421-2013; Vorobev, Alexander /C-1918-2016 OI Demenkov, Valentin/0000-0002-4016-8671; Panzhin, Andrey/0000-0001-7766-2668; Vorobev, Alexander /0000-0002-7324-428X NR 3 TC 10 Z9 11 U1 0 U2 0 PU AMER WELDING SOC PI MIAMI PA PO BOX 351040, MIAMI, FL 33135 USA SN 0043-2296 J9 WELD J JI Weld. J. PD JUN PY 1999 VL 78 IS 6 BP 55 EP 58 PG 4 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA 202KC UT WOS:000080650400016 ER PT J AU Pfeiffer, JM Askew, EW Roberts, DE Wood, SM Benson, JE Johnson, SC Fredman, MS AF Pfeiffer, JM Askew, EW Roberts, DE Wood, SM Benson, JE Johnson, SC Fredman, MS TI Effect of antioxidant supplementation on urine and blood markers of oxidative stress during extended moderate-altitude training SO WILDERNESS & ENVIRONMENTAL MEDICINE LA English DT Article DE vitamin E; vitamin C; beta-carotene; zinc; selenium; oxidative stress; antioxidants; thiobarbituric acid reactive substances; lipid hydroperoxides; 8-hydroxydeoxyguanosine; hydroxynonenal; exercise; altitude; cold ID LIPID-PEROXIDATION; VITAMIN-E; PHYSICAL PERFORMANCE; BETA-CAROTENE; EXERCISE; ACID; MUSCLE; DAMAGE; RAT; MALONDIALDEHYDE AB Objective.-To investigate the increase in oxidative stress during work at moderate altitudes due to additional energy expenditure, tissue anoxia, and UV light exposure. Methods.-Thirty US Marine Corps volunteers were divided into placebo (P) and antioxidant supplement (S) groups and tested for markers of oxidative stress before (t(0)), at the midpoint of (t(1)), and after (t(2)) 14 days of winter training at a moderate altitude (similar to 2700 m). The antioxidant supplement consisted of a daily dose of 20 000 IU beta-carotene, 400 IU vitamin E, 500 mg vitamin C, 100 mu g selenium, and 30 mg zinc. The following markers of oxidative stress were measured: urine thiobarbituric acid reactive substances (TBARSs), urine hydroxynonenal (HNE), urine 8-hydrodeoxyguanosine (8-OHdG), plasma total peroxyl radical trapping potential (TRAP), and plasma lipid hydroperoxides (LPOs). Urine was collected on a 24-hr basis at t(0), t(1), and t(2); blood samples were collected at t(0) and t(2). Results.-P group LPOs increased 30% (p < 0.05) between t(0) and t(2), whereas S group LPOs did not increase. Both groups exhibited significant increases in urine TBARSs, HNE, and 8-OHdG by t(2). Urine TBARSs, HNE, and 8-OHdG increased between t(0) and t(1) in both groups, with the greater increase in the S group. The conflicting results between the plasma and urine markers of oxidative stress may be due to a time-phase relationship. Conclusions.-The results of this study suggest that work in a moderate-altitude cold-weather environment is accompanied by increased oxidative stress, despite relatively high intakes of dietary and supplemental antioxidants. C1 Univ Utah, Coll Hlth, Div Foods & Nutr, Salt Lake City, UT 84112 USA. USN, Hlth Res Ctr, Dept Human Performance, San Diego, CA 92152 USA. Abbott Labs, Ross Prod Div, Columbus, OH USA. Marine Corps Mt Warfare Training Ctr, Bridgeport, CA USA. RP Askew, EW (reprint author), Univ Utah, Coll Hlth, Div Foods & Nutr, 239 N-HPR, Salt Lake City, UT 84112 USA. NR 50 TC 42 Z9 43 U1 2 U2 6 PU WILDERNESS MEDICAL SOC PI COLORADO SPRINGS PA 3595 E FOUNTAIN BLVD, STE A1, COLORADO SPRINGS, CO 80910 USA SN 1080-6032 J9 WILD ENVIRON MED JI Wildern. Environ. Med. PD SUM PY 1999 VL 10 IS 2 BP 66 EP 74 DI 10.1580/1080-6032(1999)010[0066:EOASOU]2.3.CO;2 PG 9 WC Public, Environmental & Occupational Health; Sport Sciences SC Public, Environmental & Occupational Health; Sport Sciences GA 222QK UT WOS:000081796100002 PM 10442154 ER PT J AU Dutka, AJ AF Dutka, AJ TI Alphonse Jaminet on caisson disease: 1871 - a commentary SO WILDERNESS & ENVIRONMENTAL MEDICINE LA English DT Article C1 USN, Natl Med Ctr, Bethesda, MD 20084 USA. RP Dutka, AJ (reprint author), USN, Natl Med Ctr, Bethesda, MD 20084 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU WILDERNESS MEDICAL SOC PI COLORADO SPRINGS PA 3595 E FOUNTAIN BLVD, STE A1, COLORADO SPRINGS, CO 80910 USA SN 1080-6032 J9 WILD ENVIRON MED JI Wildern. Environ. Med. PD SUM PY 1999 VL 10 IS 2 BP 110 EP 111 PG 2 WC Public, Environmental & Occupational Health; Sport Sciences SC Public, Environmental & Occupational Health; Sport Sciences GA 222QK UT WOS:000081796100008 PM 10532825 ER PT J AU Copper, CL Koubek, E AF Copper, CL Koubek, E TI Kinetics of the molybdate and tungstate catalyzed oxidation of iodide by hydrogen peroxide SO INORGANICA CHIMICA ACTA LA English DT Article DE catalysis; iodide oxidation; hydrogen peroxide; molybdate; tungstate ID MOLYBDENUM(VI); COMPLEXES AB Several studies of the Mo(VI) and W(VI) catalyzed reaction of H2O2 with various substrates have been documented previously. The experiments described herein attempt to settle some apparent contradictions in these reports. Specifically, the oxidation of I- with H2O2 in the presence of molybdate or tungstate ion in an acid solution was studied. The rate law for this system was found to be rate, = k(cat)[MoO42-][I-] + K-uncat[H2O2][I-]with values of k(cat) = 3.87 M-1 s(-1) and k(uncat) of 9.5 x 10(-3) M-1 s(-1) (at 27.8 degrees C). The values of Delta H-not equal for the molybdate catalyzed and uncatalyzed reactions were found to be 39.4 and 56.8 KJ mol(-1), respectively. Similarly, the value of k(cat),,, was found to be 32.7 M (-1) s (-1) and Delta H-not equal was found to be 41.1 kJ mol(-1) (at 21.8 degrees C) for the same system catalyzed with tungstate rather than molybdate. (C) 1999 Elsevier Science S.A. All rights reserved. C1 USN Acad, Annapolis, MD 21402 USA. RP Koubek, E (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 11 TC 14 Z9 14 U1 0 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0020-1693 J9 INORG CHIM ACTA JI Inorg. Chim. Acta PD MAY 30 PY 1999 VL 288 IS 2 BP 229 EP 232 DI 10.1016/S0020-1693(99)00079-1 PG 4 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 205JV UT WOS:000080818300016 ER PT J AU Paritosh Srolovitz, DJ Battaile, CC Li, X Butler, JE AF Paritosh Srolovitz, DJ Battaile, CC Li, X Butler, JE TI Simulation of faceted film growth in two-dimensions: Microstructure, morphology and texture SO ACTA MATERIALIA LA English DT Article DE chemical vapor deposition (CVD); compute simulation; grain growth; microstructure; thin films ID DIAMOND FILMS; POLYCRYSTALLINE GROWTH AB A series of simulations of the growth of polycrystalline, Faceted films From randomly oriented nuclei in two spatial dimensions was performed. The simulations track the motion of all corners where Facets from the same grain and different grains meet. Results are presented on the temporal evolution of the mean grain size, grain size distribution, surface roughness, crystallographic texture and growth zones as a function of a, a parameter describing the relative facet velocities. The mean grain size and r.m.s. surface roughness are shown to be a parabolic function of the film thickness, in agreement with experiment and theoretical results. The grain size distribution is temporally self-similar when scaled by the mean grain size and has the form of a gamma distribution. The crystallographic orientation distribution (i.e. texture) is Gaussian, peaks at an sc-dependent orientation and the peak sharpens during film growth. The peak position is well described by the largest radius vector of the appropriate idiomorph in two and three dimensions. The grain size, roughness and texture evolution are intimately linked. This type of simulation may be used to examine the evolution of the microstructure of any film which exhibits faceted growth with prescribed facet velocities. Published bl Elsevier Science Ltd. On behalf of Acta Metallurgica Inc. C1 Univ Michigan, Dept Chem Engn, Ann Arbor, MI 48109 USA. Univ Michigan, Dept Mat Sci & Engn, Ann Arbor, MI 48109 USA. Univ Michigan, Dept Phys, Ann Arbor, MI 48109 USA. Naval Res Lab, Gas Surface Dynam Sect, Washington, DC 20375 USA. RP Srolovitz, DJ (reprint author), Univ Michigan, Dept Chem Engn, Ann Arbor, MI 48109 USA. RI Butler, James/B-7965-2008 OI Butler, James/0000-0002-4794-7176 NR 22 TC 31 Z9 31 U1 0 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD MAY 28 PY 1999 VL 47 IS 7 BP 2269 EP 2281 PG 13 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 205FX UT WOS:000080811600024 ER PT J AU Patrick, HJ Wright, BM Greenblatt, AD Homrighaus, ZJ Friebele, EJ AF Patrick, HJ Wright, BM Greenblatt, AD Homrighaus, ZJ Friebele, EJ TI Athermal fibre cavity etalon for ultra-high-sensitivity strain sensing SO ELECTRONICS LETTERS LA English DT Article ID TEMPERATURE AB An ultra-high sensitivity static strain sensor with 300n epsilon/degrees C thermal apparent strain has been fabricated by constructing a fibre etalon cavity of concatenated fluoride and silica fibre sections bonded to a low thermal expansion coefficient graphite composite strut tube. The athermal cavity is 30 times less temperature-sensitive than a simple fluoride or silica cavity, while retaining the same response to physical strain. C1 USN, Res Lab, Washington, DC 20375 USA. Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. RP Patrick, HJ (reprint author), USN, Res Lab, Code 5675, Washington, DC 20375 USA. NR 4 TC 3 Z9 3 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 MAY 27 PY 1999 VL 35 IS 11 BP 920 EP 921 DI 10.1049/el:19990622 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA 208BZ UT WOS:000080971500048 ER PT J AU Edelstein, AS Harris, VG Rolison, DR Kurihara, L Smith, DJ Perepezko, J Bassani, MHD AF Edelstein, AS Harris, VG Rolison, DR Kurihara, L Smith, DJ Perepezko, J Bassani, MHD TI Inversion of surface composition and evolution of nanostructure in Cu Co nanocrystals SO APPLIED PHYSICS LETTERS LA English DT Article ID GIANT MAGNETORESISTANCE; ALLOYS AB Nanocrystals of Cu/Co with a nearly pure Cu core and a Co-rich shell have been chemically synthesized. This structure results from reaction kinetics and represents an inversion of surface composition since the surface energy of Co is larger than that of Cu. Both the Cu core and the Co-rich shell initially have an fcc structure and a common lattice constant. Annealing at temperatures in the range of 300 to 600 degrees C causes the material to phase separate, forming small, increasingly pure Co nanocrystals which aggregate on the surface of the pure Cu nanocrystals. (C) 1999 American Institute of Physics. [S0003-6951(99)02621-2]. C1 USN, Res Lab, Washington, DC 20375 USA. Arizona State Univ, Dept Phys & Astron, Tempe, AZ 85287 USA. Arizona State Univ, Ctr Solid State Sci, Tempe, AZ 85287 USA. Univ Wisconsin, Dept Mat Sci & Engn, Madison, WI 53706 USA. RP Edelstein, AS (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Harris, Vincent/A-8337-2009 NR 13 TC 15 Z9 16 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAY 24 PY 1999 VL 74 IS 21 BP 3161 EP 3163 DI 10.1063/1.124087 PG 3 WC Physics, Applied SC Physics GA 199EM UT WOS:000080467500028 ER PT J AU Mazin, II Singh, DJ AF Mazin, II Singh, DJ TI Competitions in layered ruthenates: Ferromagnetism versus antiferromagnetism and triplet versus singlet pairing SO PHYSICAL REVIEW LETTERS LA English DT Article ID SR2RUO4 AB Involvement of O in magnetism leads to ferromagnetic fluctuations in Sr2RuO4, while Ca2RuO4 is antiferromagnetic, suggesting a possibility of antiferromagnetic fluctuations in Sr2RuO4 as well. Our calculations show that the ferro- and antiferromagnetic fluctuations coexist, leading to an instability in Ca2RuO4 and to a competition between p- and d-wave superconductivities in Sr2RuO4 The antiferromagnetism is due to the nesting, with Q approximate to(2 pi/3a, 2 pi/3a, O). The p-wave state is more stable than the d-wave one except in close vicinity of the magnetic instability. The d-wave state has a vanishing gap in one out of three bands; in the p channel it is comparable in all three bands. [S0031-9007(99)09181-4]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Mazin, II (reprint author), USN, Res Lab, Code 6691, Washington, DC 20375 USA. RI Mazin, Igor/B-6576-2008; Singh, David/I-2416-2012 NR 8 TC 194 Z9 195 U1 2 U2 30 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 24 PY 1999 VL 82 IS 21 BP 4324 EP 4327 DI 10.1103/PhysRevLett.82.4324 PG 4 WC Physics, Multidisciplinary SC Physics GA 198CX UT WOS:000080405500043 ER PT J AU Perez-Prado, MT McNelley, TR AF Perez-Prado, MT McNelley, TR TI Dependence of the grain boundary misorientation distribution in Supral 2004 on the plane of observation SO SCRIPTA MATERIALIA LA English DT Article ID ALUMINUM; RECRYSTALLIZATION; NUCLEATION C1 CSIC, CENIM, Ctr Nacl Invest Met, Dept Met Phys, E-28040 Madrid, Spain. USN, Postgrad Sch, Ctr Mat Sci, Dept Mech Engn, Monterey, CA 93943 USA. RP Perez-Prado, MT (reprint author), CSIC, CENIM, Ctr Nacl Invest Met, Dept Met Phys, Avda Gregorio del Amo 8, E-28040 Madrid, Spain. RI Perez-Prado, Maria Teresa/M-2050-2014 OI Perez-Prado, Maria Teresa/0000-0003-0758-2851 NR 12 TC 6 Z9 6 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD MAY 21 PY 1999 VL 40 IS 12 BP 1401 EP 1406 DI 10.1016/S1359-6462(99)00096-2 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 213JZ UT WOS:000081270300014 ER PT J AU Ranganathan, D Haridas, V Karle, IL AF Ranganathan, D Haridas, V Karle, IL TI Diamond crowns: Design, synthesis and X-ray crystallographic studies of a novel family of adamantane-containing crown ethers SO TETRAHEDRON LA English DT Article ID HOST-GUEST COMPLEXATION; MACROCYCLE INTERACTION; KINETIC DATA; BINDING; IONOPHORES AB A novel family of crown ethers, containing adamantane units in the cyclic framework, has been designed and synthesized by a straightforward one-step procedure. The design strategy permits the incorporation of a variety of a-amino acids to provide adamantane-constrained chiral crown ethers for use as simple models in studying ion-transport and host-guest complexation. X-ray crystallographic studies on four members of this family have revealed interesting conformational features. Ion complexation studies of several members with alkali metal and ammonium ions are reported. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Indian Inst Chem Technol, Discovery Lab, Hyderabad 500007, Andhra Pradesh, India. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. RP Ranganathan, D (reprint author), Indian Inst Chem Technol, Discovery Lab, Hyderabad 500007, Andhra Pradesh, India. RI V, haridas/K-2992-2012 NR 18 TC 6 Z9 6 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0040-4020 J9 TETRAHEDRON JI Tetrahedron PD MAY 21 PY 1999 VL 55 IS 21 BP 6643 EP 6656 DI 10.1016/S0040-4020(99)00311-7 PG 14 WC Chemistry, Organic SC Chemistry GA 198QQ UT WOS:000080435800019 ER PT J AU Nguyen, VQ Sanghera, JS Kung, FH Aggarwal, ID Lloyd, IK AF Nguyen, VQ Sanghera, JS Kung, FH Aggarwal, ID Lloyd, IK TI Effect of temperature on the absorption loss of chalcogenide glass fibers SO APPLIED OPTICS LA English DT Article ID FABRICATION AB The change in the absorption loss of IR-transmitting chalcogenide glass fibers in the temperature range? of -90 degrees C less than or equal to T less than or equal to 70 degrees C was investigated. For sulfur-based glass fibers the change in loss relative to room temperature was slightly affected by the temperature in the wavelength region of 1-5 mu m. For lambda greater than or equal to 6 mu m the change in loss was mainly due to multiphonon absorption. The change in loss for tellurium-based glass fibers increased significantly at T = 60 degrees C. The increase in the loss at short wavelengths (lambda less than or equal to 4.1 mu m) was due to electronic excitations in the tail states. Between 5 and 9 mu m there was noticeable free-carrier absorption. Beyond lambda greater than or equal to 9 mu m, multiphonon absorption dominated the loss spectrum. (C) 1999 Optical Society of America. C1 USN, Div Opt Sci, Res Lab, Washington, DC 20375 USA. Virginia Polytech Inst & State Univ, Dept Elect Engn, Blacksburg, VA 24061 USA. Univ Maryland Res Fdn, Greenbelt, MD 20770 USA. Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. RP Nguyen, VQ (reprint author), USN, Div Opt Sci, Res Lab, Code 5606-1, Washington, DC 20375 USA. EM vnguyen@ccf.nrl.navy.mil RI Lloyd, Isabel/B-1513-2012 NR 19 TC 7 Z9 7 U1 0 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD MAY 20 PY 1999 VL 38 IS 15 BP 3206 EP 3213 DI 10.1364/AO.38.003206 PG 8 WC Optics SC Optics GA 197BK UT WOS:000080344600011 PM 18319910 ER PT J AU Ruffa, AA AF Ruffa, AA TI Gravitational lensing of gravitational waves SO ASTROPHYSICAL JOURNAL LA English DT Article DE Galaxy : center; gravitation; gravitational lensing AB The concentrated mass at the Galactic center is considered as a gravitational lens that focuses gravitational-wave energy to the Earth. It is found that 60 Hz gravitational waves from a rotating neutron star outside our Galaxy are focused onto a region having an approximate radius of 1.1 x 10(11) m (assuming that the concentrated mass has the form of a supermassive black hole). The increase in intensity (which is proportional to the square of the increase in strain amplitude h) is by a factor of approximately 17,000. Sources within our Galaxy lead to increases in intensity by a factor that can exceed 4000. C1 USN, Undersea Warfare Ctr Div, Newport, RI 02841 USA. RP Ruffa, AA (reprint author), USN, Undersea Warfare Ctr Div, 1176 Howell St, Newport, RI 02841 USA. NR 9 TC 15 Z9 15 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 1999 VL 517 IS 1 BP L31 EP L33 DI 10.1086/312015 PN 2 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 206TA UT WOS:000080894300008 ER PT J AU Businger, S Johnson, R Katzfey, J Siems, S Wang, Q AF Businger, S Johnson, R Katzfey, J Siems, S Wang, Q TI Smart tetroons for Lagrangian air-mass tracking during ACE 1 SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ASSIMILATION; PREDICTION; SYSTEM; MODEL AB A series of "smart" tetroons was released from shipboard during the recent ACE 1 field experiment designed to monitor changes in the sulfur budget in a remote marine boundary layer (MBL) south of Tasmania, Australia. The smart tetroons were designed at NOAA Air Resources Laboratory Field Research Division to provide air parcel tracking information. The adjective smart here refers here to the fact that the buoyancy of the tetroons automatically adjusts through the action of a pump and valves when the tetroon travels vertically outside a range of pressures set prior to tetroon release. The smart tetroon design provides GPS location, barometric pressure, temperature, relative humidity, and tetroon status data via a transponder to the NCAR C-130 research aircraft flying in the vicinity of the tetroons. In this paper we will describe (1) the design and capability of the smart tetroons and their performance during the two Lagrangian experiments conducted during ACE 1, (2) the synoptic context of the Lagrangians, including the origin of the air parcels being tracked, and (3) the results of trajectory predictions derived from the National Center for Environmental Prediction (NCEP) Global Spectral Model (GSM) and Australia's Commonwealth Scientific and Industrial Research Organization (CSIRO) Division of Atmospheric Research (DAR) limited-area model. C1 Univ Hawaii, Dept Meteorol, Honolulu, HI 96822 USA. NOAA, Air Resources Lab, Field Res Div, Idaho Falls, ID USA. CSIRO, Div Atmospher Res, PMB 1, Aspendale, Vic 3195, Australia. Monash Univ, Ctr Dynam Meteorol & Oceanog, Clayton, Vic 3168, Australia. USN, Postgrad Sch, Dept Meteorol, Monterey, CA 93943 USA. RP Businger, S (reprint author), Univ Hawaii, Dept Meteorol, 2525 Correa Rd, Honolulu, HI 96822 USA. EM businger@soest.hawaii.edu RI Siems, Steven/C-8339-2013; Katzfey, Jack/K-1231-2012; OI Katzfey, Jack/0000-0002-0604-8860; Siems, Steven/0000-0002-8478-533X NR 19 TC 20 Z9 20 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 MAY 20 PY 1999 VL 104 IS D9 BP 11709 EP 11722 DI 10.1029/1998JD100094 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 198PZ UT WOS:000080434300012 ER PT J AU Leon, C Ngai, KL AF Leon, C Ngai, KL TI Rapidity of the change of the Kohlrausch exponent of the alpha-relaxation of glass-forming liquids at T-B or T-beta and consequences SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID DIELECTRIC-RELAXATION; SUPERCOOLED LIQUIDS; NEUTRON-SCATTERING; MOLECULAR-DYNAMICS; COUPLING MODEL; O-TERPHENYL; TRANSITION; SPECTROSCOPY; CONDUCTIVITY; BEHAVIOR AB Stickel, Fischer, and Richert [J. Chem. Phys. 1996, 104, 2043] found the temperature dependence of the cc-relaxation time, tau(alpha)(T), of many small-molecule glass-forming liquids undergoes a change at a characteristic temperature, T-B. On the lowering of temperature, tau(alpha)(T) changes from one Vogel-Fulcher-Tammann (VFT) dependence, VFTh, that holds for T > T-B to another VFT dependence, VFT1, or a non-VFT dependence, nVFT(1), for T < T-B. In glass-formers, which exhibit a beta-relaxation of the Johari-Goldstein type, extrapolation of the Arrhenius temperature dependence of its relaxation time, tau(beta)(T), indicates that it tends to merge into the alpha-relaxation at a temperature, T-beta. Stickel et al. found also that T-B coincides with T-beta. This work augments these important findings by showing that, for fragile glass-formers, on decreasing temperature there is at T-B approximate to T-beta a rapid steplike change of the Kohlrausch-Williams-Watts exponent, (1 - n), of the primary alpha-relaxation correlation function, exp[-(t/tau(alpha))(1-n)]. The size of the steplike change of different glass-formers decreases proportionately with decreases in the value of n(T-g) at the glass transition temperature T-g and in the difference between VFTh and VFT1 or nVFT(1), after these functions are extended to a common temperature range above and below T-B. These correlations are interpreted as due to the onset of significant increase of cooperativity at and below T-B approximate to T beta as indicated by the rapidity of the increase of n(T) in the framework of the coupling model. If one compares different glass-formers ai the same value of the ratio, T-B/T, the interpretation corroborates the experimental fact that a larger steplike increase of (1 - n) across T-B gives rise to larger separation between the logarithm of the alpha and beta relaxation times. The fact that T-beta nearly coincides with T-B is also explained. For (T-B/T) > 1, the difference, log[tau(alpha)(T-B/T)] - log[tau(beta)(T-B/T)], remains small for strong glass-formers with small n(T-g) and small step increase of (1 - n) across T-B. As a result, a beta-relaxation peak or shoulder cannot be resolved from the a-relaxation peak and observed as a wing on the high-frequency side of the cr-relaxation peak. This interpretation can further explain the origin of the success of the Dixon-Nagel scaling of the dielectric loss data of glass-formers. C1 USN, Res Lab, Washington, DC 20375 USA. RP Ngai, KL (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Leon, Carlos/A-5587-2008 OI Leon, Carlos/0000-0002-3262-1843 NR 49 TC 86 Z9 88 U1 2 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD MAY 20 PY 1999 VL 103 IS 20 BP 4045 EP 4051 DI 10.1021/jp983756h PG 7 WC Chemistry, Physical SC Chemistry GA 200XH UT WOS:000080565100010 ER PT J AU Doi, M Ishida, T Kobayashi, M Deschamps, JR Flippen-Anderson, JL AF Doi, M Ishida, T Kobayashi, M Deschamps, JR Flippen-Anderson, JL TI The highly solvated structure of theonella-peptolide Id, a tridecapeptide lactone from the Okinawa marine sponge Theonella swinhoei SO ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS LA English DT Article ID NATURAL-PRODUCTS AB Theonellapeptolide Id (TNLP-Id), C70H125N13O16 . 12H(2)O, was crystallized from an aqueous methanol solution. This crystalline cyclic tridecapeptide is solvated by 12 water molecules, which interact with the backbone. All the solvent molecules are located on one face of the hydrophobic peptide. This suggests that the molecule also has unanticipated amphipathic properties. The uniquely folded cyclic backbone is composed of short and long turn units. C1 Osaka Univ Pharmaceut Sci, Osaka 56911, Japan. Osaka Univ, Fac Pharmaceut Sci, Suita, Osaka 565, Japan. USN, Struct Matter Lab, Res Lab, Washington, DC 20375 USA. RP Doi, M (reprint author), Osaka Univ Pharmaceut Sci, 4-20-1 Nasahara, Osaka 56911, Japan. EM doit@oysun01.oups.ac.jp OI Deschamps, Jeffrey/0000-0001-5845-0010 NR 11 TC 6 Z9 6 U1 0 U2 6 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0108-2701 J9 ACTA CRYSTALLOGR C JI Acta Crystallogr. Sect. C-Cryst. Struct. Commun. PD MAY 15 PY 1999 VL 55 BP 796 EP 798 DI 10.1107/S0108270198014383 PN 5 PG 3 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 202QX UT WOS:000080664600040 ER PT J AU Johnson, GM Clenney, TL AF Johnson, GM Clenney, TL TI Gomco circumcision SO AMERICAN FAMILY PHYSICIAN LA English DT Letter ID RING BLOCK C1 USN Hosp, Jacksonville, FL 32214 USA. RP Johnson, GM (reprint author), USN Hosp, 2080 Child St, Jacksonville, FL 32214 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 USA SN 0002-838X J9 AM FAM PHYSICIAN JI Am. Fam. Physician PD MAY 15 PY 1999 VL 59 IS 10 BP 2724 EP 2724 PG 1 WC Primary Health Care; Medicine, General & Internal SC General & Internal Medicine GA 199MK UT WOS:000080485800003 PM 10348064 ER PT J AU Wang, YR Sheeley, NR Howard, RA Rich, NB Lamy, PL AF Wang, YR Sheeley, NR Howard, RA Rich, NB Lamy, PL TI Streamer disconnection events observed with the LASCO coronagraph SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MASS EJECTIONS; MAGNETIC-STRUCTURES; TOPOLOGY; ORIGIN AB We present Large Angle Spectrometric Coronagraph (LASCO) observations of two events that suggest magnetic disconnection in coronal streamers. During the 1-2 days preceding each event, successions of narrow looptops are seen rising slowly through the 2-6 R-S field of view forming a bright streamer stalk which continues to elongate with time. As the streamer becomes ever more constricted, it eventually severs at a heliocentric distance of similar to 4 R-S. The lower part of the stalk collapses back to form a cusplike structure extending to similar to 3 R-S, while the disconnected segment is observed as a kink or density enhancement that propagates outward with a speed of order 200 km s(-1). We interpret these non-CME events as transient openings and closings of magnetic flux rooted at the boundaries of coronal holes. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Astron Spatiale Lab, F-13376 Marseille 12, France. Interferometr Inc, Chantilly, VA USA. RP Wang, YR (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. NR 14 TC 31 Z9 31 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 15 PY 1999 VL 26 IS 10 BP 1349 EP 1352 DI 10.1029/1999GL900177 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 197PR UT WOS:000080374500001 ER PT J AU Yates, SW AF Yates, SW TI Androgen abuse: The price of growth and performance SO HOSPITAL PRACTICE LA English DT Article ID ANABOLIC-STEROID USE; TESTOSTERONE; MASS C1 USN Hosp, Dept Internal Med, Jacksonville, FL 32214 USA. RP Yates, SW (reprint author), USN Hosp, Dept Internal Med, Jacksonville, FL 32214 USA. OI Yates, Scott/0000-0002-5197-0686 NR 9 TC 1 Z9 1 U1 1 U2 1 PU MCGRAW HILL HEALTHCARE PUBLICATIONS PI MINNEAPOLIS PA 4530 WEST 77TH ST, MINNEAPOLIS, MN 55435-5000 USA SN 8750-2836 J9 HOSP PRACT JI Hosp. Pract. PD MAY 15 PY 1999 VL 34 IS 5 BP 113 EP + PG 3 WC Medicine, General & Internal SC General & Internal Medicine GA 195BN UT WOS:000080229400008 PM 10340038 ER PT J AU Mied, RP Shen, CY Lindemann, GJ Evans, TE AF Mied, RP Shen, CY Lindemann, GJ Evans, TE TI Symmetric baroclinic instability during frontogenesis with horizontal density gradients and ageostrophic vertical shears SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID NUMERICAL-MODEL; FRONT; FLUID AB This work examines the stability of surface frontogenesis in the presence of a horizontal density gradient and an ageostrophic current. We pose an initial value problem, in which two homogeneous bodies of water with different densities are separated by a horizontal transition region for the density. A surface current jet flows along the density front, and the geostrophic adjustment process is simulated using a fully nonlinear pseudo spectral numerical calculation in a 10 km x 30 m range and depth domain. We allow the evolution of the surface current jet but do not permit its variation in the y direction (perpendicular to the computational domain). A number of simulations are performed for a wide range of density differences and jet strengths. Surface frontogenesis and a tendency toward geostrophic adjustment of the initially ageostrophic fields do not always exhibit a smooth subsurface circulation accompanying the bunching of the surface isopycnals. Instead, a vortex is sometimes shed from the vicinity of the evolving front, and the isopycnals are distorted by this smaller-scale vortical flow. To determine the source of the secondary symmetric baroclinic instability, the acceleration potential of the individual terms in the vorticity equation is calculated. The instability is caused by the vertical shear in the along-front jet, which is intensified by the advection and vortex-tilting processes during the frontogenesis. Although this vortex is left behind by the propagating hydraulic jump, it subsequently matures into a secondary hydraulic jump on its own. We found that in marginally unstable cases an increase in the kinematic viscosity can suppress its occurrence. Finally, we show that the unstable vortex is separate and distinct from the captured turbulent rotor which is thought to be locally trapped at a location just behind the propagating front. C1 USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Mied, RP (reprint author), USN, Res Lab, Remote Sensing Div, Code 7250,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 17 TC 2 Z9 2 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD MAY 15 PY 1999 VL 104 IS C5 BP 10903 EP 10915 DI 10.1029/1998JC900111 PG 13 WC Oceanography SC Oceanography GA 198WX UT WOS:000080448200001 ER PT J AU Ardhuin, F Pinot, JM Tintore, J AF Ardhuin, F Pinot, JM Tintore, J TI Numerical study of the circulation in a steep canyon off the Catalan coast (western Mediterranean) SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID SUBMARINE CANYONS; WIND; CURRENTS; FLOWS; SEA AB We use a limited-area fine-resolution primitive equation model to carry out a case study of the circulation in the steep and narrow Blanes Canyon, located off the Catalan coast (western Mediterranean). This area is characterized by a permanent along-slope density-driven current and strong northerly and easterly wind bursts in autumn. In a first step the slope current is allowed to adjust to the bottom topography, leading to a stationary circulation pattern which presents large vertical variations related to the canyon geometry. In the surface layer the strong stratification allows the current to flow straight over the canyon rim, ignoring bottom topography. In the intermediate layer the canyon is wide, and waters are isolated in a geostrophic anticyclonic eddy maintained by friction at the edge of the slope current. In the deep layer the canyon is narrow, and a topographic upwelling lifts bottom waters toward the canyon head. In a second step the circulation is forced by easterly (along-shore with the coast on its right) and northerly (seaward) 1-day wind bursts which induce significant vertical and cross-shore motions steered by the bottom slope. This ageostrophic circulation is substantially amplified in the canyon where the flow pattern presents large-amplitude oscillations characterized by a downwelling (upwelling) during the easterly (northerly) wind burst followed by a rebound upwelling (downwelling) as the wind relaxes. The upwelling induced by the northerly wind burst is capable of renewing waters trapped in the canyon eddy. Our results appear to be in fairly good agreement with in situ physical and biogeochemical data collected in Blanes Canyon and comparable canyons of the world ocean. The three-dimensional features obtained in this study can explain some of the observed patterns of larvae distribution and exchanges between the coastal zone and the open sea. C1 Univ Illes Balears, Inst Mediterrani Estudis Avancats, CSIC, E-07071 Palma de Mallorca, Spain. USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. RP Ardhuin, F (reprint author), USN, Postgrad Sch, Dept Oceanog, 833 Dyer Rd, Monterey, CA 93943 USA. RI Ardhuin, Fabrice/A-1364-2011 OI Ardhuin, Fabrice/0000-0002-9309-9681 NR 28 TC 31 Z9 31 U1 0 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD MAY 15 PY 1999 VL 104 IS C5 BP 11115 EP 11135 DI 10.1029/1999JC900029 PG 21 WC Oceanography SC Oceanography GA 198WX UT WOS:000080448200016 ER PT J AU Plant, WJ Weissman, DE Keller, WC Hessany, V Hayes, K Hoppel, KW AF Plant, WJ Weissman, DE Keller, WC Hessany, V Hayes, K Hoppel, KW TI Air sea momentum transfer and the microwave cross section of the sea SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID WAVE GENERATION; SURFACE-WAVES; WIND-WAVES; STRESS; DEPENDENCE; OCEAN; FLUX; MODEL; DRAG; SPECTRA AB Measurements of atmospheric fluxes of heat, moisture, and momentum were made simultaneously and coincidentally with microwave backscatter measurements from an airship flown over the Pacific Ocean in 1993. The measurement technique was well suited to measure fluxes at very low wind speeds because the airship required an air speed near 10 m s(-1) in order to maintain altitude. The measurements show that very low wind speeds are always associated with very low microwave cross sections and very high air/sea drag coefficients. The occurrence of regions of very low wind speed is not usually correlated with either the sea surface temperature or the air/sea temperature difference. Nevertheless, these regions can remain in place for time periods of several hours. The rate of increase of the microwave cross section at very low wind speeds agrees with that predicted by Donelan and Pierson [1987], but the absolute value of the threshold wind speed appears to be lower than their prediction. The high drag coefficient at low wind speeds is due to the fact that the friction velocity is nearly constant for wind speeds below 4-5 m s(-1). Thus, at these wind speeds the increase of the microwave cross section follows the behavior of the wind speed rather than the wind stress. At higher wind speeds, however, the behavior is reversed with the cross section following the wind stress at a constant wind speed. We suggest that this behavior can be understood if momentum transfer across the air/sea interface is supported by both viscosity and the entire spectrum of waves on the surface, as many investigators have indicated. C1 Univ Washington, Appl Phys Lab, Seattle, WA 98105 USA. USN, Res Lab, Washington, DC 20175 USA. Hofstra Univ, Hempstead, NY 11550 USA. RP Plant, WJ (reprint author), Univ Washington, Appl Phys Lab, Seattle, WA 98105 USA. NR 29 TC 14 Z9 14 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD MAY 15 PY 1999 VL 104 IS C5 BP 11173 EP 11191 DI 10.1029/1999JC900038 PG 19 WC Oceanography SC Oceanography GA 198WX UT WOS:000080448200020 ER PT J AU Lin, RQ Perrie, W AF Lin, RQ Perrie, W TI Wave-wave interactions in finite depth water SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID NONLINEAR ENERGY-TRANSFER; SPECTRUM; PARAMETERIZATIONS; COMPUTATIONS AB In this study we present a new formulation for the nonlinear wave-wave interaction source function in finite water depth. The formulation, denoted the reduced integration approximation (RIA), is shown to compare well with published formulations, both for shallow water wave-wave interactions [Herterich and Hasselmann, 1980; Polnikov, 1997; Hashimoto et al., 1998; A. Masuda and K. Komatsu, manuscript in preparation, 1998] and also for the asymptotic deep water limit: (1) the Hamiltonian formulation proposed by Lin and Perie [1997], by (2) Hasselmann and Hasselmann [1981], and (3) the line integral transformation of Web [1978] and Resio and Perrie [1991]. Of these deep water formulations, that of Lin-Perrie generalizing the Hamiltonian representation of Zakharov [1968] to finite depth water, is notable for its simplicity, efficiency and its ability to apply to very shallow water (kh approximate to 0.3), and highly nonlinear (epsilon less than or equal to 0.3) interactions. RIA is based on an analysis of the main resonance domain, which reduces the six-dimensional integration to a quasi-line integral to minimize computational time. In terms of computational time, RIA is a thousand times faster than the EXACT-NL version formulated by Hasselmann and Hasselmann [1981], with similar accuracy. Thus RIA can be considered a candidate for operational forecasting in finite depth water, in the sense that the discrete interaction approximation was presented as a candidate for operational deep water wave forecasting by Hasselmann et al. [1988]. C1 NSWC, Carderock Div, Hydromech Directorate, Bethesda, MD 20817 USA. Fisheries & Oceans Canada, Bedford Inst Oceanog, Dartmouth, NS B2Y 4A2, Canada. RP NSWC, Carderock Div, Hydromech Directorate, Code 5500,David Taylor Model Basin,9500 MacArt, Bethesda, MD 20817 USA. EM rlin@wave2.dt.navy.mil NR 30 TC 15 Z9 17 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9275 EI 2169-9291 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD MAY 15 PY 1999 VL 104 IS C5 BP 11193 EP 11213 DI 10.1029/1999JC900026 PG 21 WC Oceanography SC Oceanography GA 198WX UT WOS:000080448200021 ER PT J AU Chu, PC Lu, SH Liu, WT AF Chu, PC Lu, SH Liu, WT TI Uncertainty of South China Sea prediction using NSCAT and National Centers for Environmental Prediction winds during tropical storm Ernie, 1996 SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID OCEAN AB Error propagation from winds to ocean models was numerically investigated using the Princeton Ocean Model (POM) for the South China Sea with 20-km horizontal, resolution and 23 sigma levels conforming to a realistic bottom topography during the lifetime of tropical cyclone Ernie (November 4-18, 1996). Numerical integration was divided into preexperimental and experimental stages. The preexperiment phase generates the initial conditions on November 1 for the sensitivity experiment. During the experimental stage the POM was integrated from November 1 to 30, 1996 under National Centers for Environmental Prediction (NCEP) reanalyzed surface fluxes along with two surface wind data sets, namely, the daily averaged interpolated NASA scatterometer winds and the NCEP winds. The relative root-mean-square differences fluctuate from 0.5 to 1.0 for winds, 0.25 to 0.7 for surface elevations, 0.47 to 1.02 for surface currents, and 0 to 0.23 for surface temperatures. This indicates that the model has less uncertainty overall than the wind fields used to drive it, which in turn suggests that the ocean modeling community may progress without waiting for the atmospheric modelers to build the perfect forecast model. C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Acad Sinica, Inst Plateau Atmospher Phys, Lanzhou 730000, Peoples R China. RP Chu, PC (reprint author), USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. NR 20 TC 18 Z9 19 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD MAY 15 PY 1999 VL 104 IS C5 BP 11273 EP 11289 DI 10.1029/1998JC900046 PG 17 WC Oceanography SC Oceanography GA 198WX UT WOS:000080448200028 ER PT J AU Peng, MS Jeng, BF Williams, RT AF Peng, MS Jeng, BF Williams, RT TI A numerical study on tropical cyclone intensification. Part I: Beta effect and mean flow effect SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID BOUNDARY-LAYER; VORTEX; HURRICANES; SIMULATION; GENESIS; MOTION; MODEL; STORM AB The effect of planetary vorticity gradient (beta) and the presence of a uniform mean flow on the intensification of tropical cyclones are studied using a limited-area primitive equation model. The most intense storm evolves on a constant-f plane with zero-mean how and its structure is symmetric with respect to the vortex center. The presence of an environmental how induces an asymmetry in a vortex due to surface friction. When f varies the vortex is distorted by the beta gyres. Fourier analysis of the wind field shows that a deepening cyclone is associated with a small asymmetry in the low-level wavenumber-one wind held. A small degree of asymmetry in the wind field allows a more symmetric distribution of the surface fluxes and low-level moisture convergence. On the other hand, a weakening or nonintensifying cyclone is associated with a larger asymmetry in its wave-number-one wind field. This flow pattern generates asymmetric moisture convergence and surface fluxes and a phase shift may exist between their maxima. The separation of the surface flux maximum and the lateral moisture convergence reduces precipitation and inhibits the development of the tropical cyclone. Since die orientation of the asymmetric circulation induced by beta is in the southeast to northwest direction, the asymmetry induced by a westerly Row partially cancels the beta effect asymmetry while that of an easterly flow enhances it. Therefore, in a variable-f environment, westerly flows are more favorable for tropical cyclone intensification than easterly flows of the same speed. C1 USN, Res Lab, Marine Meteorol Div, Monterey, CA 93943 USA. USN, Postgrad Sch, Dept Meteorol, Monterey, CA 93943 USA. RP Peng, MS (reprint author), USN, Res Lab, Marine Meteorol Div, Code 7533, Monterey, CA 93943 USA. NR 32 TC 46 Z9 59 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD MAY 15 PY 1999 VL 56 IS 10 BP 1404 EP 1423 DI 10.1175/1520-0469(1999)056<1404:ANSOTC>2.0.CO;2 PG 20 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 194YM UT WOS:000080222400010 ER PT J AU Chu, PC AF Chu, PC TI Two kinds of predictability in the Lorenz system SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article AB The Lorenz system is used to discuss two kinds of predictability: the model sensitivity to inaccurate initial conditions (first kind) and to inaccurate boundary conditions (second kind). The first kind of predictability has been investigated for a long time, but not the second kind. It was found that the Lorenz system has a capability to detect both kinds of predictability since the boundary condition is represented by a model parameter, r. Two sensitivity runs are designed by perturbing the initial condition and the model parameter r by the same small relative error (10(-4)), which is equivalent to 10% of the instrumentational accuracy for surface temperature measurement. Comparison of model output between the control run and the sensitivity runs shows that the model error growth and the growing period are comparable between the two kinds of predictability. This indicates the importance of preparing accurate boundary conditions in numerical prediction. C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. RP Chu, PC (reprint author), USN, Postgrad Sch, Dept Oceanog, Code OC-CU, Monterey, CA 93943 USA. NR 3 TC 21 Z9 21 U1 1 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD MAY 15 PY 1999 VL 56 IS 10 BP 1427 EP 1432 DI 10.1175/1520-0469(1999)056<1427:TKOPIT>2.0.CO;2 PG 6 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 194YM UT WOS:000080222400012 ER PT J AU Goldberg, L Koplow, JP Kliner, DAV AF Goldberg, L Koplow, JP Kliner, DAV TI Highly efficient 4-W Yb-doped fiber amplifier pumped by a broad-stripe laser diode SO OPTICS LETTERS LA English DT Article AB A Yb-doped double-cladding fiber amplifier is v-groove side pumped by a 100-mu m-wide, broad-stripe, 975-nm laser diode. The amplifier exhibits, separately, 39% electrical-to-optical conversion efficiency, 89% internal optical-to-optical conversion efficiency, 4-W output power at 1060 nm, and a small-signal gain of 53 dB. (C) 1999 Optical Society of America OCIS codes: 060.2320, 140.3510, 140.4480. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Goldberg, L (reprint author), USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. NR 11 TC 75 Z9 80 U1 0 U2 4 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD MAY 15 PY 1999 VL 24 IS 10 BP 673 EP 675 DI 10.1364/OL.24.000673 PG 3 WC Optics SC Optics GA 197DH UT WOS:000080349000013 PM 18073819 ER PT J AU Bozdog, C Przybylinska, H Watkins, GD Harle, V Scholz, F Mayer, M Kamp, M Molnar, RJ Wickenden, AE Koleske, DD Henry, RL AF Bozdog, C Przybylinska, H Watkins, GD Harle, V Scholz, F Mayer, M Kamp, M Molnar, RJ Wickenden, AE Koleske, DD Henry, RL TI Optical detection of electron paramagnetic resonance in electron-irradiated GaN SO PHYSICAL REVIEW B LA English DT Article ID MAGNETIC-RESONANCE; NATIVE DEFECTS; PHOTOLUMINESCENCE AB 2.5 MeV electron irradiation of wurtzite GaN epitaxially grown on sapphire substrates greatly reduces its near-UV and visible luminescence, producing two bands in the near infrared. In one of these, a broad structureless band centered at similar to 0.95 eV, three optically detected S = 1/2 electron paramagnetic resonances (ODEPR) are observed. Two of these display well-resolved hyperfine interaction with a single Ga nucleus, suggesting that they are interstitial-Ga related. The second band has a sharp zero-phonon line at 0.88 eV End accompanying phonon-assisted structure and reveals an S = 1 ODEPR signal, as yet not identified. [S0163-1829(99)05719-7]. C1 Lehigh Univ, Dept Phys, Bethlehem, PA 18015 USA. Univ Stuttgart, Inst Phys 4, D-70550 Stuttgart, Germany. Univ Ulm, Abt Optoelekt, D-89081 Ulm, Germany. MIT, Lincoln Lab, Lexington, MA 02173 USA. USN, Res Lab, Code 6861, Washington, DC 20375 USA. RP Bozdog, C (reprint author), Lehigh Univ, Dept Phys, Bldg 16, Bethlehem, PA 18015 USA. NR 23 TC 52 Z9 54 U1 0 U2 6 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 15 PY 1999 VL 59 IS 19 BP 12479 EP 12486 DI 10.1103/PhysRevB.59.12479 PG 8 WC Physics, Condensed Matter SC Physics GA 200ZU UT WOS:000080570800056 ER PT J AU Kenyon, NS Chatzipetrou, M Masetti, M Ranuncoli, A Oliveria, M Wagner, JL Kirk, AD Harlan, DM Burkly, LC Ricordi, C AF Kenyon, NS Chatzipetrou, M Masetti, M Ranuncoli, A Oliveria, M Wagner, JL Kirk, AD Harlan, DM Burkly, LC Ricordi, C TI Long-term intrahepatic islet allograft survival in nonhuman primates treated with anti-CD154 monotherapy SO TRANSPLANTATION LA English DT Meeting Abstract C1 Univ Miami, Sch Med, Dept Med, Miami, FL USA. Univ Miami, Sch Med, Dept Surg, Miami, FL USA. Univ Miami, Sch Med, Dept Vet Resources, Miami, FL USA. Univ Miami, Sch Med, Diabet Res Inst, Miami, FL USA. USN, Med Res Inst, Bethesda, MD USA. Biogen Inc, Cambridge, MA 02142 USA. RI Kirk, Allan/B-6905-2012 NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0041-1337 J9 TRANSPLANTATION JI Transplantation PD MAY 15 PY 1999 VL 67 IS 9 MA 32 BP S550 EP S550 DI 10.1097/00007890-199905150-00057 PG 1 WC Immunology; Surgery; Transplantation SC Immunology; Surgery; Transplantation GA 201YD UT WOS:000080624100052 ER PT J AU Urban, JJ von Tersch, RL AF Urban, JJ von Tersch, RL TI A computational study of charge delocalization and ring fluoro substituent effects in 4-fluoromethylphenoxides SO JOURNAL OF ORGANIC CHEMISTRY LA English DT Article ID MOLECULAR-ORBITAL METHODS; AQUEOUS-SOLUTION; BENZYL FLUORIDE; CONFORMATIONAL-ANALYSIS; SOLVATION MODELS; FREE-ENERGIES; BASIS-SETS; GAS-PHASE; POTENTIALS; DENSITY AB The degree of charge delocalization in 4-fluoromethylphenoxide anions has been investigated with ab initio molecular orbital calculations at the Hartree-Fock and MP2 levels and with the B3LYP density functional using the 6-31+G(d) and 6-311+G(2d,p) basis sets, The effect of aqueous solvation on the rotational profiles has been investigated using the AM1-SM2 solvation model. These anions serve as model systems for fluorinated tyrosine derivatives, which have been used as substrates for the enzyme tyrosine phenol-lyase. The importance of the double-bond/no-bond resonance structure has been assessed through an analysis of conformational profiles, geometries and charge distribution. The effect of ring fluorination on the degree of charge delocalization was investigated to aid in the interpretation of previous experimental mechanistic studies of the tyrosine phenol-lyase enzyme. Calculations were also carried out on benzyl fluoride, and the inclusion of diffuse functions was found to result in the perpendicular conformation as the predicted lowest-energy conformation by a small margin. Previous studies with smaller basis sets found the planar structure to be the lowest-energy conformation. The results indicate that the placement of an electron-donating group (O-) in the para ring position acts to increase the fluoride character of the fluoromethyl group and that this effect is not substantially modulated by the placement of fluorines on the ring. C1 USN Acad, Dept Chem, Annapolis, MD 21402 USA. RP Urban, JJ (reprint author), USN Acad, Dept Chem, 572 Holloway Rd, Annapolis, MD 21402 USA. NR 36 TC 1 Z9 1 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0022-3263 J9 J ORG CHEM JI J. Org. Chem. PD MAY 14 PY 1999 VL 64 IS 10 BP 3409 EP 3416 DI 10.1021/jo981392j PG 8 WC Chemistry, Organic SC Chemistry GA 198MV UT WOS:000080428700006 ER PT J AU Linders, JTM Flippen-Anderson, JL George, CF Rice, KC AF Linders, JTM Flippen-Anderson, JL George, CF Rice, KC TI An expedient synthesis of 9-keto-2-methyl-5-(dimethoxyphenyl)morphans SO TETRAHEDRON LETTERS LA English DT Article DE Thorpe-Ziegler reaction; alkylation; phenylmorphans ID RECEPTOR SUBTYPE SELECTIVITY; AMINATION AB An expedient synthesis of ortho-methoxy substituted 9-keto-5-phenylmorphans has been developed, featuring a Thorpe-Zieger cyclization to construct the substituted 2-phenylcyclohexanone intermediate. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 NIDDKD, Med Chem Lab, NIH, Bethesda, MD 20892 USA. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. RP Linders, JTM (reprint author), Janssen Res Fdn, Dept Med Chem, Turnhoutseweg 30, B-2340 Beerse, Belgium. NR 19 TC 7 Z9 7 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0040-4039 J9 TETRAHEDRON LETT JI Tetrahedron Lett. PD MAY 14 PY 1999 VL 40 IS 20 BP 3905 EP 3908 DI 10.1016/S0040-4039(99)00566-3 PG 4 WC Chemistry, Organic SC Chemistry GA 193HV UT WOS:000080130600024 ER PT J AU Boos, JB Yang, MJ Bennett, BR Park, D Kruppa, W Bass, R AF Boos, JB Yang, MJ Bennett, BR Park, D Kruppa, W Bass, R TI Low-voltage, high-speed AlSb InAsSb HEMTs SO ELECTRONICS LETTERS LA English DT Article ID ALSB/INAS HEMTS AB Antimonide-based HEMTs have heen fabricated with an InAsSb channel. Infra-red photoluminescence measurements at 5K confirm that the addition of Sb changes the band structure from a staggered type II heterojunction lineup to a type I. These HEMTs with 0.1 mu m gate length exhibit decreased output conductance and improved voltage gain. At V-DS = 0.6V, a microwave transconductance of 700mS/mm and an output conductance of 110mS/mm were obtained corresponding to a voltage gain of 6. C1 USN, Res Lab, Washington, DC 20375 USA. RP Boos, JB (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 20 Z9 20 U1 2 U2 3 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 MAY 13 PY 1999 VL 35 IS 10 BP 847 EP 848 DI 10.1049/el:19990536 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA 204DD UT WOS:000080746900063 ER PT J AU Georgiou, IT Schwartz, IB AF Georgiou, IT Schwartz, IB TI Dynamics of large scale coupled structural mechanical systems: A singular perturbation proper orthogonal decomposition approach SO SIAM JOURNAL ON APPLIED MATHEMATICS LA English DT Article DE mechanics; linear nonlinear dynamics; singular perturbation; slow invariant manifold; proper orthogonal decomposition ID INVARIANT-MANIFOLDS; DAMPED PENDULUM; STATES; SLOW AB We have combined the theories of geometric singular perturbation and proper orthogonal decomposition to study systematically the dynamics of coupled systems in mechanics involving coupling between continuous structures and nonlinear oscillators. Here we analyze a prototypical structural/mechanical system consisting of a planar nonlinear pendulum coupled to a flexible rod made of linear viscoelastic material. We cast the equations of motion in a singularly perturbed set of oscillators and compute analytic approximations to an attractive global invariant manifold in phase space of the coupled system. The invariant manifold, two-dimensional for the unforced system and three-dimensional for the forced system, carries a continuum of slow motions. For a sufficiently stiff rod, a proper orthogonal decomposition of any long time motion extracts a single structure for the spatial coherence of the dynamics, which is a realization of the slow invariant manifold. As the flexibility of the rod increases, the energy of periodic and chaotic motions is shown to spread to multiple coherent structures, indicating a high degree-of-freedom attractor. C1 USN, Special Project Nonlinear Sci, Res Lab, Washington, DC 20375 USA. RP Georgiou, IT (reprint author), USN, Special Project Nonlinear Sci, Res Lab, Code 6700-3, Washington, DC 20375 USA. RI Schwartz, Ira/A-8073-2009 NR 21 TC 45 Z9 46 U1 0 U2 2 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0036-1399 J9 SIAM J APPL MATH JI SIAM J. Appl. Math. PD MAY 13 PY 1999 VL 59 IS 4 BP 1178 EP 1207 DI 10.1137/S0036139997299802 PG 30 WC Mathematics, Applied SC Mathematics GA 199TC UT WOS:000080497500002 ER PT J AU Klypin, A Gottlober, S Kravtsov, AV Khokhlov, AM AF Klypin, A Gottlober, S Kravtsov, AV Khokhlov, AM TI Galaxies in N-body simulations: Overcoming the overmerging problem SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology : theory; galaxies : formation; galaxies : halos; large-scale structure of universe; methods : numerical ID COLD DARK-MATTER; LARGE-SCALE STRUCTURE; TULLY-FISHER RELATION; X-RAY-CLUSTERS; LUMINOSITY FUNCTION; DYNAMICAL FRICTION; VELOCITY BIAS; RICH CLUSTERS; COSMOLOGICAL CONSTANT; ADIABATIC INVARIANTS AB We present analysis of the evolution of dark matter halos in dense environments of groups and clusters in dissipationless cosmological simulations. The premature destruction of halos in such environments, known as "the overmerging," reduces the predictive power of N-body simulations and makes difficult any comparison between models and observations. We analyze the possible processes that cause the overmerging and assess the extent to which this problem can be cured with current computer resources and codes. Using both analytic estimates and high-resolution numerical simulations, we argue that the overmerging is mainly due to the lack of numerical resolution. We find that the force and mass resolution required for a simulated halo to survive in galaxy groups and clusters is extremely high and was almost never reached before: similar to 1-3 kpc and 10(8)-10(9) M., respectively. We use the high-resolution Adaptive Refinement Tree (ART) N-body code to run cosmological simulations with particle mass approximate to 2 x 10(8) h(-1) M. and spatial resolution approximate to 1-2 h(-1) kpc and show that in these simulations the halos do survive in regions that would appear overmerged with lower force resolution. Nevertheless, the halo identification in very dense environments remains a challenge even with resolution this high. We present two new halo-finding algorithms developed to identify both isolated and satellite halos that are stable (existed at previous moments) and gravitationally bound. To illustrate the use of the satellite halos that survive the overmerging, we present a series of halo statistics, which can be compared with those of observed galaxies. Particularly, we find that, on average, halos in groups have the same velocity dispersion as the dark matter particles; i.e., they do not exhibit significant velocity bias. The small-scale (100 kpc to 1 Mpc) halo correlation function in both models is well described by the power law xi proportional to r(-1.7) and is in good agreement with observations. It is slightly antibiased (b approximate to 0.7-0.9) relative to the dark matter. To test other galaxy statistics, we use the maximum of the halo rotation velocity and the Tully-Fisher relation to assign luminosity to the halos. For two cosmological models, a flat model with the cosmological constant and Omega(0) = 1 - Omega(Lambda) = 0.3, h = 0.7 and a model with a mixture of cold and hot dark matter and Omega(0) = 1.0, Omega(v) = 0.2, h = 0.5, we construct luminosity functions and evaluate mass-to-light ratios in groups. Both models produce luminosity functions and mass-to-light ratios (similar to 200-400) that are in reasonable agreement with observations. The latter implies that the mass-to-light ratio in galaxy groups (at least for M-vir less than or similar to 3 x 10(13) h(-1) M. analyzed here) is not a good indicator of Omega(0). C1 New Mexico State Univ, Dept Astron, Las Cruces, NM 88003 USA. USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. RP New Mexico State Univ, Dept Astron, Las Cruces, NM 88003 USA. NR 79 TC 356 Z9 358 U1 0 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 1999 VL 516 IS 2 BP 530 EP 551 DI 10.1086/307122 PN 1 PG 22 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 205FQ UT WOS:000080811000004 ER PT J AU Satyapal, S Watson, DM Forrest, WJ Pipher, JL Fischer, J Greenhouse, MA Smith, HA Woodward, CE AF Satyapal, S Watson, DM Forrest, WJ Pipher, JL Fischer, J Greenhouse, MA Smith, HA Woodward, CE TI Probing the dust-enshrouded regions of the interacting galaxy system ARP 299: A near-infrared study SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : individual (Arp 299); galaxies : nuclei; infrared : galaxies; infrared : ISM : lines and bands ID MICRON EMISSION FEATURE; STARBURST GALAXIES; SUPERNOVA-REMNANTS; STAR-FORMATION; LUMINOSITY FUNCTION; RECOMBINATION-LINE; SPIRAL GALAXIES; STANDARD STARS; RADIO-SOURCES; GAMMA-RATIO AB We present high spectral resolution (lambda/delta lambda congruent to 10(3)) Pa beta(1.28 mu m) and Br gamma(2.17 mu m), 3.29 mu m dust feature, and near-infrared broadband images of the Arp 299 = NGC 3690/IC 694 galaxy system. The emission is found to be concentrated at the positions of three active regions, known as sources A, B, and C. From our Br gamma/Pa beta flux ratio we find the visual extinction toward the ionized gas in A, B, and C is similar to 6, 6, and 2 magnitudes, respectively, assuming case B recombination and a foreground screen geometry for the obscuring material. Our observations can be explained entirely by a starburst model for the Arp 299 system. The putative active galactic nucleus (AGN) in source A does not dominate the properties of this source. We see no evidence of broad recombination lines. In addition, the ratio of the 3.29 mu m dust feature to total luminosity, a tracer of starburst activity, is consistent in each source with that seen in M82 and other starburst galaxies. Also, our imaging observations reveal that the dust feature emission is concentrated in the nucleus of source A, contrary to the extended annular distribution of the feature emission seen surrounding the nucleus of the more distant Seyfert galaxy NGC 7469. In this galaxy, the absence of the feature emission in the nucleus has been attributed to the destruction of the dust carriers in the hard radiation held surrounding the AGN. Our observations suggest that all of the active regions in Arp 299 are characterized by starburst episodes. The observed CO indices and Br gamma equivalent widths imply that source B is older than source A and source C is the youngest star-forming region. Although these regions are probably complex physical systems not necessarily characterized by a single coeval population of stars, we have compared our observations with an instantaneous starburst model with a Salpeter initial mass function. Using this simple model, we find starburst ages of similar to 6 x 10(6), 8 x 10(6), and 4 x 10(6) for sources A, B, and C, respectively. C1 Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Wyoming, Dept Phys & Astron, Laramie, WY 82701 USA. RP NASA, Goddard Space Flight Ctr, Code 685, Greenbelt, MD 20771 USA. EM satyapal@stars.gsfc.nasa.gov NR 54 TC 14 Z9 14 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 1999 VL 516 IS 2 BP 704 EP 715 DI 10.1086/307130 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 205FQ UT WOS:000080811000018 ER PT J AU Katz-Stone, DM Rudnick, L Butenhoff, C O'Donoghue, AA AF Katz-Stone, DM Rudnick, L Butenhoff, C O'Donoghue, AA TI Coaxial jets and sheaths in wide-angle-tailed radio galaxies SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : individual (1231+674,1433+553); galaxies : jets; galaxies : kinematics and dynamics; galaxies : structure; polarization ID DECELERATING RELATIVISTIC JETS; RILEY TYPE-I; ABELL CLUSTERS; VLA OBSERVATIONS; SPECTRUM; BRIGHTNESS; MODEL AB We add 20, 6, and 3.6 cm VLA observations of two wide-angle tails (WATs), 1231 + 674 and 1433 + 553, to existing VLA data at 6 and 20 cm in order to study the variations of spectral index as a function of position. We apply the spectral tomography process that we introduced in our analysis of 3C 67, 3C 190, and 3C 449 (Katz-Stone; Katz-Stone & Rudnick). Both spectral tomography and polarization maps indicate that there are two distinct extended components in each source. As in the case of 3C 449, we find that each source has a flat spectrum jet surrounded by a steeper spectrum sheath. The steep components tend to be more highly polarized than the flat components. We discuss a number of possibilities for the dynamics of the jet/sheath systems and the evolution of their relativistic electron populations. Although the exact nature of these two coaxial components is still uncertain, their existence requires new models of jets in FR I sources and may also have implications for the dichotomy between FR I and FR II galaxies. C1 USN Acad, Annapolis, MD 21402 USA. Univ Minnesota, Minneapolis, MN 55455 USA. St Lawrence Univ, Canton, NY 13617 USA. RP Katz-Stone, DM (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 42 TC 18 Z9 18 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 1999 VL 516 IS 2 BP 716 EP 728 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 205FQ UT WOS:000080811000019 ER PT J AU Kiriakidis, K AF Kiriakidis, K TI Non-linear control system design via fuzzy modelling and LMIs SO INTERNATIONAL JOURNAL OF CONTROL LA English DT Article; Proceedings Paper CT Workshop on Multiple Model Approaches to Modelling and Control CY SEP, 1997 CL TRONDHEIM, NORWAY ID OUTPUT PARAMETRIC MODELS; H-INFINITY CONTROL; NONLINEAR-SYSTEMS; ROBUST STABILIZATION; STABILITY ANALYSIS; IDENTIFICATION; ISSUES AB The method of fuzzy-model-based control has emerged as an alternative approach to the solution of analysis and synthesis problems associated with plants that exhibit complex non-linear behaviour. At present, the literature in this field has addressed the control design problem related to the stabilization of state-space fuzzy models. In practical situations, however, when perturbations exist in the state-space model, the problem becomes one of robust stabilization that has yet to be posed and solved. The present paper contributes in this direction through the development of a framework that exploits the distinctive property of the fuzzy model as the convex hull of linear system matrices. Using such a quasi-linear model structure, the robust stabilization of complex non-linear systems, against modelling error and parametric uncertainty, based on static state or dynamic output feedback, is reduced to a linear matrix inequality (LMI) problem. C1 USN Acad, Dept Weapons & Syst Engn, Annapolis, MD 21402 USA. RP USN Acad, Dept Weapons & Syst Engn, 105 Maryland Ave, Annapolis, MD 21402 USA. EM kiriakid@novell.nadn.navy.mil NR 32 TC 26 Z9 26 U1 0 U2 3 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 2-4 PARK SQUARE, MILTON PARK, ABINGDON OR14 4RN, OXON, ENGLAND SN 0020-7179 EI 1366-5820 J9 INT J CONTROL JI Int. J. Control PD MAY 10 PY 1999 VL 72 IS 7-8 BP 676 EP 685 DI 10.1080/002071799220858 PG 10 WC Automation & Control Systems SC Automation & Control Systems GA 193ET UT WOS:000080123500009 ER PT J AU Cochran, JR Fornari, DJ Coakley, BJ Herr, R Tivey, MA AF Cochran, JR Fornari, DJ Coakley, BJ Herr, R Tivey, MA TI Continuous near-bottom gravity measurements made with a BGM-3 gravimeter in DSV Alvin on the East Pacific Rise crest near 9 degrees 31 ' N and 9 degrees 50 ' N SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID SEISMIC VELOCITY STRUCTURE; SPREADING MIDOCEAN RIDGES; DE-FUCA RIDGE; SEA-FLOOR; OCEANIC-CRUST; VOLCANIC-ERUPTIONS; UPPER-MANTLE; EVOLUTION; 9-DEGREES-10-DEGREES-N; DISCONTINUITIES AB A Bell BGM-3 gravimeter has been used to collect continuous, underway, near-bottom (3- to 10-m altitude) gravity measurements from the deep-diving submersible DSV Alvin during surveys on the East Pacific Rise (EPR) crest near 9 degrees 31'N and 9 degrees 50'N. Closely spaced (20- to 30-m) gravity measurements were made along transects up to 8 km long in both regions. Repeatability of measurements made at the same location on different dives is similar to 0.3 mGal. Along-track spatial resolution of anomalies is similar to 130-160 m, with the limiting factors being precision and sampling rate of the pressure gauge depth data used to calculate vertical accelerations of the submersible. The average upper crustal density of the ridge crest determined from the relationship between depth and free-water gravity anomalies varies greatly between 9 degrees 31'N and 9 degrees 50'N. Average upper crustal densities of 2410 kg/m(3) for the 9 degrees 50'N area and 2690 kg/m3 for the 9 degrees 31'N area were calculated. The different densities are not due to differing geometry of the Layer 2A-2B boundary or a regional cross-axis gravity gradient. Differences in porosity of the shallow crustal rocks, or a difference in the proportion of low density extrusives to higher-density dikes and sills within Layer 2A in these two areas, are the likely causes of the different upper crustal densities. Bouguer gravity anomalies near the EPR axis are primarily small amplitude (0.5-2 mGal), are a few hundred meters across, and appear to be lineated parallel to the axis. Larger-amplitude Bouguer anomalies of up to 4 mGal were found at a few locations across the crestal plateau and are associated with pillow ridges composed of lavas which are clearly younger than the surrounding seafloor. These ridges have distinct chemical compositions compared to lavas from the axial summit collapse trough (ASCT) at the same latitude. Probable sources of the 0.5- to 2-mGal anomalies observed on the summit plateau include areas of collapsed and fissured terrain and dike swarms feeding melt through Layer 2A to the surface. A grid survey of the ridge axis near 9 degrees 50'N shows Bouguer anomalies lineated along the axis, suggesting that dike swarms do contribute to the observed Bouguer anomalies. The along-axis continuity of the gravity anomalies is disrupted at a 75-m offset of the ASCT, suggesting that shallow feeders of lava to the surface may be segmented on a finer scale than the deeper crustal magmatic system. This initial study confirms the ability to conduct high-resolution, near-bottom, continuous gravity measurements from Alvin. It also provides important information on how the shallow crustal structure of a fast spreading mid-ocean ridge develops and how it varies with the surface morphology. C1 Columbia Univ, Lamont Doherty Geol Observ, Palisades, NY 10964 USA. Woods Hole Oceanog Inst, Dept Geol & Geophys, Woods Hole, MA USA. USN, Oceanog Off, Stennis Space Facil Ctr, Bay St Louis, MS USA. RP Columbia Univ, Lamont Doherty Geol Observ, Palisades, NY 10964 USA. EM jrc@ldeo.columbia.edu RI Tivey, Maurice/E-9247-2015 OI Tivey, Maurice/0000-0003-0821-1155 NR 54 TC 36 Z9 36 U1 0 U2 3 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 MAY 10 PY 1999 VL 104 IS B5 BP 10841 EP 10861 DI 10.1029/1999JB900049 PG 21 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 194PD UT WOS:000080202000028 ER PT J AU Cao, XA Pearton, SJ Donovan, SM Abernathy, CR Ren, F Zolper, JC Cole, MW Zeitouny, A Eizenberg, M Shul, RJ Baca, AG AF Cao, XA Pearton, SJ Donovan, SM Abernathy, CR Ren, F Zolper, JC Cole, MW Zeitouny, A Eizenberg, M Shul, RJ Baca, AG TI Thermal stability of WSix and W ohmic contacts on GaN SO MATERIALS SCIENCE AND ENGINEERING B-SOLID STATE MATERIALS FOR ADVANCED TECHNOLOGY LA English DT Article DE thermal stability; ohmic contacts; metallization AB We have sputter-deposited 500-1200 Angstrom thick WSi0.45 and W metallization onto both n(+) GaN (n = 10(19) cm(-3)) doped either during MOCVD growth or by direct Si+ ion implantation (5 x 10(15) cm(-2), 100 keV) activated by RTA at 1400 degrees C for 10 s and p(+) (N-A = 10(18) cm(-3)) GaN. In the n-type epi samples R-c values of 10(-4) Ohm cm(-2) were obtained and were stable to similar to 1000 degrees C. The annealing treatments up to 600 degrees C had little effect on the WSix/GaN interface, but the beta-W2N phase formed between 700-800 degrees C, concomitant with a strong reduction (approximately a factor of 2) in near-surface crystalline defects in the GaN. Spiking of the metallization down the threading and misfit dislocations was observed at 800 degrees C, extending > 5000 Angstrom in some cases. This can create junction shorting in bipolar or thyristor devices. R-c values of similar to 10(-6) Ohm cm(-2) were obtained on the implanted samples for 950 degrees C annealing, with values of similar to 10(-5) Ohm cm(-2) after 1050 degrees C anneals. On p-GaN, the contacts are essentially leaky Schottky diodes at 25 degrees C. but became ohmic at greater than or equal to 250 degrees C, with R-c in the 10(-3) Ohm cm(-2) range. The W-based metallization is much more thermally stable than the more common Ni/Au. (C) 1999 Elsevier Science S.A. All rights reserved. C1 Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Univ Florida, Dept Chem Engn, Gainesville, FL 32611 USA. Off Naval Res, Arlington, VA 22217 USA. USA, Res Lab, WMRD, Aberdeen Proving Ground, MD 21105 USA. Technion Israel Inst Technol, Dept Mat Engn, IL-32000 Haifa, Israel. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Pearton, SJ (reprint author), Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. NR 10 TC 3 Z9 3 U1 0 U2 4 PU ELSEVIER SCIENCE SA 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 MAY 6 PY 1999 VL 59 IS 1-3 BP 362 EP 365 DI 10.1016/S0921-5107(98)00351-1 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 203CB UT WOS:000080689000076 ER PT J AU Eaton, PE Pramod, K Emrick, T Gilardi, R AF Eaton, PE Pramod, K Emrick, T Gilardi, R TI Building with cubane-1,4-diyl. Synthesis of aryl-substituted cubanes, p-[n]cubyls, and cubane-separated bis(arenes) SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID ELECTRON-TRANSFER; CRYSTAL; TRANSITION; BIPHENYL; PHASE; BONDS; POLYPHENYLENES; HYDROCARBONS; TINKERTOYS; OLIGOMERS AB On treatment with an organolithium 1,4-diiodocubane generates cubane-1,4-diyl, a highly reactive species, shown here to be a versatile precursor to numerous aryl substituted cubanes, available now for the first time in high yield. The diyl is demonstrated to provide a good route to bicubyl and its derivatives. A kind of "living polymerization" of the diyl is developed to give the p-[n]cubyls. These oligomers are rigid rods made up of cubanes linked together at the 1 and 4 positions, each cubane adding similar to 4.15 Angstrom to the length. The properties of these rods, some more than 15 Angstrom long, are discussed, as are methods for modifying their solubility. X-ray crystallographic analyses of some of these compounds an presented, with emphasis on packing parameters. C1 Univ Chicago, Dept Chem, Chicago, IL 60637 USA. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. RP Eaton, PE (reprint author), Univ Chicago, Dept Chem, 5735 S Ellis Ave, Chicago, IL 60637 USA. NR 51 TC 24 Z9 24 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD MAY 5 PY 1999 VL 121 IS 17 BP 4111 EP 4123 DI 10.1021/ja983441f PG 13 WC Chemistry, Multidisciplinary SC Chemistry GA 196HN UT WOS:000080303100003 ER PT J AU Olafsen, LJ Vurgaftman, I Bewley, WW Felix, CL Aifer, EH Meyer, JR Waterman, JR Mason, W AF Olafsen, LJ Vurgaftman, I Bewley, WW Felix, CL Aifer, EH Meyer, JR Waterman, JR Mason, W TI Negative luminescence from type-II InAs/GaSb superlattice photodiodes SO APPLIED PHYSICS LETTERS LA English DT Article ID DEVICES AB Strong negative luminescence is displayed by type-II InAs/GaSb superlattice diodes under reverse bias. The negative emittance at room temperature is as high as 1.5 mu W/cm(2) meV at 4.9 mu m, and the negative efficiency at 3.5 mu m is 41% of the emission from a perfect blackbody at that temperature. The main features of the data are reproduced by a detailed photodiode simulation. (C) 1999 American Institute of Physics. [S0003-6951(99)05218-3]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Olafsen, LJ (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Olafsen, Linda/G-4996-2013 NR 16 TC 36 Z9 36 U1 1 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAY 3 PY 1999 VL 74 IS 18 BP 2681 EP 2683 DI 10.1063/1.123935 PG 3 WC Physics, Applied SC Physics GA 190PE UT WOS:000079972400039 ER PT J AU Romero, MJ Araujo, D Garcia, R Walters, RJ Summers, GP Messenger, SR AF Romero, MJ Araujo, D Garcia, R Walters, RJ Summers, GP Messenger, SR TI Radiation-induced order-disorder transition in p(+)-n InGaP solar cells SO APPLIED PHYSICS LETTERS LA English DT Article ID TEMPERATURE-DEPENDENCE; GROWTH TEMPERATURE; V/III RATIO; GA0.5IN0.5P; HETEROSTRUCTURES AB The effects of electron and proton irradiation on p(+)-n InGaP solar cells grown on GaAs substrates are investigated using cathodoluminescence (CL) and transmission electron microscopy (TEM). The CL measurements confirm the higher radiation resistance and defect annealing properties of InGaP compared to those of GaAs. The CL measurements also indicate the occurrence of a radiation-induced sublattice order-disorder transition in InGaP. TEM reveals the presence of ordering domains in the as-grown cells, which are effectively removed by radiation-induced defects. The results should be useful in the fabrication of radiation-resistant single-junction and dual-junction InGaP solar cells for space. (C) 1999 American Institute of Physics. [S0003-6951(99)01517-X]. C1 Univ Cadiz, Fac Ciencias, Dept Ciencia Mat & IM & QI, E-11510 Puerto Real, Spain. USN, Res Lab, Washington, DC 20375 USA. SFA Inc, Largo, MD 20744 USA. RP Romero, MJ (reprint author), Univ Cadiz, Fac Ciencias, Dept Ciencia Mat & IM & QI, E-11510 Puerto Real, Spain. OI Garcia Roja, Rafael/0000-0003-2867-7016 NR 17 TC 9 Z9 9 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAY 3 PY 1999 VL 74 IS 18 BP 2684 EP 2686 DI 10.1063/1.123936 PG 3 WC Physics, Applied SC Physics GA 190PE UT WOS:000079972400040 ER PT J AU Lai, YC Bollt, E Grebogi, C AF Lai, YC Bollt, E Grebogi, C TI Communicating with chaos using two-dimensional symbolic dynamics SO PHYSICS LETTERS A LA English DT Article ID GENERALIZED SYNCHRONIZATION; SYSTEMS; OSCILLATORS; SIGNALS AB Symbolic representations of controlled chaotic orbits produced by signal generators can be used for communicating. In this Letter, communicating with chaos is investigated by using more realistic dynamical systems described by two-dimensional invertible maps. The major difficulty is how to specify a generating partition so that a good symbolic dynamics can be defined. A solution is proposed whereby hyperbolic chaotic saddles embedded in the attractor are exploited for digital encoding. Issues addressed include the channel capacity and noise immunity when these saddles are utilized for communication. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Univ Kansas, Dept Phys & Astron, Lawrence, KS 66045 USA. Univ Kansas, Dept Math, Lawrence, KS 66045 USA. USN Acad, Dept Math, Annapolis, MD 21402 USA. Univ Maryland, Inst Phys Sci & Technol, Dept Math, Inst Plasma Res, College Pk, MD 20742 USA. RP Lai, YC (reprint author), Univ Kansas, Dept Phys & Astron, Lawrence, KS 66045 USA. NR 21 TC 34 Z9 36 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 MAY 3 PY 1999 VL 255 IS 1-2 BP 75 EP 81 DI 10.1016/S0375-9601(99)00175-9 PG 7 WC Physics, Multidisciplinary SC Physics GA 193ZT UT WOS:000080168200012 ER PT J AU Saunders, M Fox, AG Midgley, PA AF Saunders, M Fox, AG Midgley, PA TI Quantitative zone-axis convergent-beam electron diffraction (CBED) studies of metals. I. Structure-factor measurements SO ACTA CRYSTALLOGRAPHICA SECTION A LA English DT Article ID ATOMIC SCATTERING FACTORS; CHARGE-DENSITY; BAND-STRUCTURE; COPPER AB The zone-axis CBED pattern-matching technique ZAPMATCH [Bird gr Saunders (1992). Ultramicroscopy, 45, 241-251] has been applied to low-order structure-factor measurements in nickel and copper. Considerable disagreement exists between previously published results obtained with a variety of solid-state theories and experimental techniques. The nickel ZAPMATCH results confirm previous electron-diffraction critical-voltage measurements and are in excellent agreement with FLAPW (full-potential linearized augmented plane-wave) theory calculations. This is further proof of the accuracy achievable with ZAPMATCH analysis. For copper, however, while the results support the findings of previous experimental measurements, they are consistently higher than those given by a range of solid-state theories, perhaps demonstrating some limitation in the existing theory. Two extensions to the ZAPMATCH technique are also considered. First, rules are developed to determine the number of structure factors that can be refined accurately from a given CBED pattern. Second, the imaginary potential generally introduced to account for the effects of thermal diffuse scattering (TDS) is also refined. It is shown that, while the widely used Einstein model is a useful approximation, the refined values are consistently higher than the model predicts. In addition, the importance of a second-order (real) TDS correction arising from the Einstein model is investigated. Although its effects are limited in this instance, it may prove to be more significant at lower beam energies or for materials of higher atomic number. C1 USN, Postgrad Sch, Dept Mech Engn, Ctr Mat Sci & Engn, Monterey, CA 93943 USA. Univ Cambridge, Dept Mat Sci & Met, Cambridge CB2 3QZ, England. RP Saunders, M (reprint author), Univ Uppsala, Angstrom Lab, Box 534, S-75121 Uppsala, Sweden. RI Saunders, Martin/B-3082-2011 OI Saunders, Martin/0000-0001-6873-7816 NR 26 TC 27 Z9 28 U1 0 U2 9 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-7673 J9 ACTA CRYSTALLOGR A JI Acta Crystallogr. Sect. A PD MAY 1 PY 1999 VL 55 BP 471 EP 479 DI 10.1107/S0108767398012604 PN 3 PG 9 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 198AL UT WOS:000080399500008 ER PT J AU Saunders, M Fox, AG Midgley, PA AF Saunders, M Fox, AG Midgley, PA TI Quantitative zone-axis convergent-beam electron diffraction (CBED) studies of metals. II. Debye-Waller-factor measurements SO ACTA CRYSTALLOGRAPHICA SECTION A LA English DT Article ID ELEMENTAL CRYSTALS AB Quantitative CBED techniques, such as the ZAPMATCH zone-axis pattern-matching method [Bird & Saunders (1992). Ultramicroscopy, 45, 241-251], have been applied with great success to the accurate refinement of low-order structure factors. The major limitation on the accuracy of the structure-factor measurements is uncertainty in the Debye-Waller factors describing the temperature-dependent atomic vibrations. While X-ray and neutron diffraction techniques are both capable of accurate measurements of Debye-Waller factors, the frequent use of liquid-nitrogen-cooled samples in CBED experiments means that previous measurements are rarely available at the temperatures required. This has prompted attempts to determine Debye-Waller factors from electron diffraction data obtained under experimental conditions that match those used for the quantitative CBED work. In this paper, the possibility of extracting accurate Debye-Waller factors from the low-order reflections of a zone-axis CBED pattern is investigated. In this way, the Debye-Waller factors and structure factors could be obtained from the same data set. With this new approach, it is shown that errors lower than +/-0.02 Angstrom(2) can be obtained for the measurement of Debye-Waller factors from room- and liquid-nitrogen-temperature nickel and copper [110] zone-axis data. The results obtained are compared with previous measurements and theoretical predictions. C1 USN, Postgrad Sch, Dept Mech Engn, Ctr Mat Sci & Engn, Monterey, CA 93943 USA. Univ Cambridge, Dept Mat Sci & Met, Cambridge CB2 3QZ, England. RP Saunders, M (reprint author), Univ Uppsala, Angstrom Lab, Box 534, S-75121 Uppsala, Sweden. RI Saunders, Martin/B-3082-2011 OI Saunders, Martin/0000-0001-6873-7816 NR 19 TC 18 Z9 19 U1 0 U2 9 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-7673 J9 ACTA CRYSTALLOGR A JI Acta Crystallogr. Sect. A PD MAY 1 PY 1999 VL 55 BP 480 EP 488 DI 10.1107/S0108767398016316 PN 3 PG 9 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 198AL UT WOS:000080399500009 ER PT J AU Li, HY Perozzo, MA Konnert, JH Nadarajah, A Pusey, ML AF Li, HY Perozzo, MA Konnert, JH Nadarajah, A Pusey, ML TI Determining the molecular-packing arrangements on protein crystal faces by atomic force microscopy SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID TETRAGONAL LYSOZYME CRYSTALS; HABIT-CONTROLLING FACTOR; EGG-WHITE LYSOZYME; IN-SITU; COMBINATORIAL COMPATIBILITY; MACROMOLECULAR CRYSTALS; GROWTH MECHANISMS; VIRUS CRYSTALS; CRYSTALLIZATION; VISUALIZATION AB Previous atomic force microscopy (AFM) studies and periodic bond-chain (PBC) analyses of tetragonal lysozyme crystals have suggested that the (110) face consists of chains of molecules related to one another by 4(3) axes parallel to the crystal face. In this study, high-resolution AFM images of the (110) face were obtained and analyzed in order to verify this prediction. A computer program was employed which constructs the theoretical AFM image corresponding to a specific crystallographic molecular-packing arrangement and AFM tip shape. The packing arrangement and tip shape were varied in order to obtain the maximum possible correlation between experimental and theoretical images. The prediction from PBC analysis of an arrangement involving 4(3) helices was confirmed in this manner, while the alternate arrangement, consisting of molecules related to one another by 2(1) axes, was not observed. However, the surface structure was found to differ significantly even from this crystallographic arrangement. The molecules were found to pack slightly closer about what will become the 4(3) axes within the interior of the crystal, suggesting the occurrence of surface reconstruction or rearrangement on the tetragonal lysozyme (110) face. This study represents a new approach for more precise determination of the molecular-packing arrangements on protein crystal faces employing AFM. C1 Univ Toledo, Dept Chem & Environm Engn, Toledo, OH 43606 USA. USN, Res Lab, Lab Struct Matter 6030, Washington, DC 20375 USA. NASA, George C Marshall Space Flight Ctr, Biophys Branch ES76, Huntsville, AL 35812 USA. RP Li, HY (reprint author), Univ Toledo, Dept Chem & Environm Engn, Toledo, OH 43606 USA. 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 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD MAY PY 1999 VL 55 BP 1023 EP 1035 DI 10.1107/S090744499900339X PN 5 PG 13 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 198AN UT WOS:000080399700009 PM 10216299 ER PT J AU Fureby, C Grinstein, FF AF Fureby, C Grinstein, FF TI Monotonically integrated large eddy simulation of free shear flows SO AIAA JOURNAL LA English DT Article; Proceedings Paper CT AIAA 36th Aerospace Sciences Meeting CY JAN 12-15, 1998 CL RENO, NV SP Amer Inst Aeronaut & Astronaut ID TURBULENT FLOWS; ISOTROPIC TURBULENCE; HOMOGENEOUS TURBULENCE; NUMERICAL SIMULATIONS; TRANSPORT ALGORITHM; ENERGY-TRANSFER; SCALE MODELS; STATISTICS; TRANSITION; VISCOSITY AB With a view to ensure that proper interaction between resolvable or grid scale and subgrid scale (SGS) motions are mimicked, it is vital to determine the necessary physics that must be built into the SGS models, In ordinary large eddy simulation (LES) approaches, models are introduced for closure in the low pass filtered Navier-Stokes equations (NSEs), which are the ones solved numerically. A promising LES approach is monotonically integrated LES (MILES), which involves solving the unfiltered NSE using high-resolution monotone algorithms; in this approach, implicit SGS models, provided by intrinsic nonlinear high-frequency filters built into the convection discretization, are coupled naturally to the resolvable scales of the flow. Formal properties of the effectual SGS modeling using MILES are documented using databases of simulated homogeneous turbulence and transitional freejets; mathematical and physical aspects of (implicit) SGS modeling through the use of nonlinear flux limiters are addressed in this context. Comparison of MILES and other conventional LES models applied to free shear hows are presented to confirm that the concept of LES is virtually independent of the SGS model if the resolution is fine enough to ensure that the cutoff wave number lies in the inertial subrange, provided that the LES model can adequately channel kinetic energy out of the resolved scales near the cutoff wave number, to prevent spurious energy buildup and aliasing. C1 FOA Def Res Estab, Dept Weapons & Protect, Div Warheads & Prop, S-17290 Stockholm, Sweden. USN, Res Lab, Lab Computat Phys & Fluid, Washington, DC 20375 USA. RP FOA Def Res Estab, Dept Weapons & Protect, Div Warheads & Prop, S-17290 Stockholm, Sweden. NR 53 TC 161 Z9 163 U1 1 U2 3 PU AMER INST AERONAUTICS ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0001-1452 EI 1533-385X J9 AIAA J JI AIAA J. PD MAY PY 1999 VL 37 IS 5 BP 544 EP 556 DI 10.2514/2.772 PG 13 WC Engineering, Aerospace SC Engineering GA 195HK UT WOS:000080244400003 ER PT J AU Gentry, BC Viera, AJ AF Gentry, BC Viera, AJ TI A subtle ECG SO AMERICAN FAMILY PHYSICIAN LA English DT Article C1 USN Hosp, Jacksonville, FL 32214 USA. RP Gentry, BC (reprint author), USN 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 USA SN 0002-838X J9 AM FAM PHYSICIAN JI Am. Fam. Physician PD MAY 1 PY 1999 VL 59 IS 9 BP 2581 EP 2582 PG 2 WC Primary Health Care; Medicine, General & Internal SC General & Internal Medicine GA 194YR UT WOS:000080222800018 PM 10323363 ER PT J AU Ross, G McDevitt, ER Chronister, R Ove, PN AF Ross, G McDevitt, ER Chronister, R Ove, PN TI Treatment of simple elbow dislocation using an immediate motion protocol SO AMERICAN JOURNAL OF SPORTS MEDICINE LA English DT Article ID JOINT AB The results of treatment after closed reduction of elbow dislocation vary. Twenty consecutive patients with closed posterior elbow dislocations were treated prospectively on a rapid motion, nonimmobilized functional regimen. This treatment protocol emphasizes immediate active range of motion under close supervision. No slings or splints were employed. Final range of motion averaged -4 degrees to 139 degrees. All patients attained final extension within 5 degrees of the contralateral side. Each patient achieved his final range of motion within an average of 19 days after reduction of the dislocation. Arm circumference returned to normal at an average of 6.5 days. There was one redislocation. After treatment, all patients met qualification for graduation from the U.S. Naval Academy and were able to pursue unrestricted athletic and career options. Our findings suggest that an aggressive immediate motion rehabilitation allows nearly full final elbow motion and an excellent functional outcome. C1 USN Acad, NMCLA, Dept Orthopaed Surg, Annapolis, MD 21402 USA. USN Acad, Dept Sports Med, Annapolis, MD 21402 USA. USN Acad, Dept Athlet Training, Annapolis, MD 21402 USA. RP Ross, G (reprint author), USN Acad, NMCLA, Dept Orthopaed Surg, 250 Woods Rd, Annapolis, MD 21402 USA. NR 13 TC 31 Z9 31 U1 0 U2 1 PU AMER ORTHOPAEDIC SOC SPORT MED PI WALTHAM PA 230 CALVARY STREET, WALTHAM, MA 02154 USA SN 0363-5465 J9 AM J SPORT MED JI Am. J. Sports Med. PD MAY-JUN PY 1999 VL 27 IS 3 BP 308 EP 311 PG 4 WC Orthopedics; Sport Sciences SC Orthopedics; Sport Sciences GA 199MQ UT WOS:000080486400007 PM 10352765 ER PT J AU Gray, GC Kaiser, KS Hawksworth, AW Watson, HL AF Gray, GC Kaiser, KS Hawksworth, AW Watson, HL TI No serologic evidence of an association found between Gulf War service and Mycoplasma fermentans infection SO AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE LA English DT Article ID OPERATION-DESERT-STORM; PERSIAN-GULF; SAUDI-ARABIA; RESPIRATORY-DISEASE; MILITARY PERSONNEL; VISCERAL INFECTION; LEISHMANIA-TROPICA; VIRUS-INFECTION; US VETERANS; SHIELD AB Occult occupational infection with Mycoplasma fermentans has been proposed as a cause for illness among Persian Gulf War veterans. Symptom data and sera from a 1994-1995 cross-sectional survey of Navy Seabees were used to select symptomatic and asymptomatic Gulf War veterans and nondeployed veterans to evaluate this hypothesis. Survey sera from 96 Seabees were matched to prewar (before September 1990) archived sera. Immunoblot serologic analyses were performed for M. fermentans in a controlled, blinded fashion. Both Gulf War veterans and nondeployed veterans had prewar and postwar serologic evidence of M. fermentans infection consistent with natural infection data. Among study subjects collectively, and stratified by Gulf War service, none of the immunoblot banding profiles (prewar or postwar) or their changes over time were associated with postwar symptoms. These serologic data do not support the hypothesis that Gulf War veterans have experienced Gulf War-related morbidity from M. fermentans infection. C1 USN, Hlth Res Ctr, Emerging Illness Div, Dept Hlth Sci & Epidemiol, San Diego, CA 92186 USA. Univ Alabama, Dept Microbiol, Birmingham, AL 35294 USA. RP Gray, GC (reprint author), USN, Hlth Res Ctr, Emerging Illness Div, Dept Hlth Sci & Epidemiol, POB 85122, San Diego, CA 92186 USA. NR 71 TC 11 Z9 11 U1 2 U2 2 PU AMER SOC TROP MED & HYGIENE PI MCLEAN PA 8000 WESTPARK DRIVE SUITE 130, MCLEAN, VA 22101 USA SN 0002-9637 J9 AM J TROP MED HYG JI Am. J. Trop. Med. Hyg. PD MAY PY 1999 VL 60 IS 5 BP 752 EP 757 PG 6 WC Public, Environmental & Occupational Health; Tropical Medicine SC Public, Environmental & Occupational Health; Tropical Medicine GA 198TE UT WOS:000080439600008 PM 10344648 ER PT J AU Gray, GC Kaiser, KS Hawksworth, AW Hall, FW Barrett-Connor, E AF Gray, GC Kaiser, KS Hawksworth, AW Hall, FW Barrett-Connor, E TI Increased postwar symptoms and psychological morbidity among US Navy Gulf War veterans SO AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE LA English DT Article ID OPERATION-DESERT-SHIELD; SERUM FERRITIN LEVELS; AL ESKAN DISEASE; PERSIAN-GULF; MILITARY PERSONNEL; RESPIRATORY-DISEASE; BIRTH-DEFECTS; STORM; EXPOSURE; STRESS AB To investigate reports on war-related morbidity, 527 active-duty Gulf War veterans and 970 nondeployed veterans from 14 Seabee commands were studied in 1994 with a questionnaire, sera collection, handgrip strength, and pulmonary function testing. The questionnaire assessed postwar symptoms, war exposures, and screened for chronic fatigue syndrome, post-traumatic stress disorder, and psychological symptoms suggesting neurosis (Hopkins Symptom Checklist). Sera were tested with four nonspecific reactant assays: C-reactive protein, transferrin, ferritin, and haptoglobin. Gulf War veterans reported a higher prevalence for 35 of 41 symptoms, scored higher on psychological symptom scales, were more likely to screen for post-traumatic stress disorder, had lower handgrip strength, and had higher serum ferritin assay results. Numerous comparisons of these morbidity outcomes with 30 self-reported exposures demonstrated many associations, but no unique exposure or group of exposures were implicated. Morbidity data are consistent with other postwar observations, but the etiology for morbidity findings remains uncertain. C1 USN, Hlth Sci Ctr, Emerging Illness Div, San Diego, CA 92186 USA. USN, Med Ctr, Dept Pathol, San Diego, CA 92134 USA. Univ Calif San Diego, Dept Family & Prevent Med 0607, San Diego, CA 92093 USA. RP Gray, GC (reprint author), USN, Hlth Sci Ctr, Emerging Illness Div, POB 85122, San Diego, CA 92186 USA. NR 85 TC 76 Z9 78 U1 2 U2 5 PU AMER SOC TROP MED & HYGIENE PI MCLEAN PA 8000 WESTPARK DRIVE SUITE 130, MCLEAN, VA 22101 USA SN 0002-9637 J9 AM J TROP MED HYG JI Am. J. Trop. Med. Hyg. PD MAY PY 1999 VL 60 IS 5 BP 758 EP 766 PG 9 WC Public, Environmental & Occupational Health; Tropical Medicine SC Public, Environmental & Occupational Health; Tropical Medicine GA 198TE UT WOS:000080439600009 PM 10344649 ER PT J AU McKeown, DA Bell, MI Etz, ES AF McKeown, DA Bell, MI Etz, ES TI Raman spectra and vibrational analysis of the trioctahedral mica phlogopite SO AMERICAN MINERALOGIST LA English DT Article ID 4-MEMBERED SILICATE RINGS; BENITOITE BATISI3O9; GLASS STRUCTURE AB Raman spectra were measured and normal mode calculations were performed for phlogopite. Calculated fundamental mode frequencies were fit to observed frequencies assigned to features in the two polarized Raman spectra collected, so that unambiguous assignment of eigenmodes could be made to nearly all Raman spectral features. Average force constant values determined for Si-O and O-Si-O environments as well as for the non-silicate environments in cyclosilicates and gillespite provided an excellent starting point for the phlogopite calculations that quickly converged to a best fit of theoretical mode frequencies to the observed Raman fundamental mode frequencies. Final values of the force constants for T-O stretch and O-T-O bend are within the range of force constant values determined for Si-O and O-Si-O environments in cyclosilicates and gillespite. The force constant similarities extend to the K-O, M(1,2)-O bond stretch and M(1,2)-O-T bond bend environments. Raman-active modes at frequencies greater than 850 cm(-1) are localized intra-sheet modes dominated by T-O stretch and O-T-O bend motions. Raman-active modes between 350 and 850 cm(-1) are dominated by mixtures of internal sheer modes with displacements from the M2 sites. Raman-active lattice modes are calculated at frequencies less than 350 cm-l. Calculated frequencies for the IR-active A(u) and B-u, modes generally fall within the frequency ranges of broad bands in the IR spectra for phlogopite presented elsewhere. Eigenmodes calculated fur phlogopite are generally unique to that mica structure and differ from those determined fur the cyclosilicates and gillespite. The few eigenmodes calculated for phlogopite that resemble those calculated for the cyclosilicates are the most localized T-O stretch motions and are assigned to the highest frequency modes. C1 Catholic Univ Amer, Vitreous State Lab, Washington, DC 20064 USA. USN, Res Lab, Dynam Solids Branch, Washington, DC 20375 USA. Natl Inst Stand & Technol, Surface Microanal Sci Div, Gaithersburg, MD 20899 USA. RP McKeown, DA (reprint author), Catholic Univ Amer, Vitreous State Lab, 320 Michigan Ave NE, Washington, DC 20064 USA. NR 13 TC 35 Z9 35 U1 1 U2 6 PU MINERALOGICAL SOC AMER PI WASHINGTON PA 1015 EIGHTEENTH ST, NW SUITE 601, WASHINGTON, DC 20036 USA SN 0003-004X J9 AM MINERAL JI Am. Miner. PD MAY-JUN PY 1999 VL 84 IS 5-6 BP 970 EP 976 PG 7 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA 196HT UT WOS:000080303500034 ER PT J AU Phillips, GW Readshaw, AK Brown, GO Weiss, RG Guardala, NA Price, JL Mueller, SC Moscovitch, M AF Phillips, GW Readshaw, AK Brown, GO Weiss, RG Guardala, NA Price, JL Mueller, SC Moscovitch, M TI Observation of radiation effects on three-dimensional optical random-access-memory materials for use in radiation dosimetry SO APPLIED RADIATION AND ISOTOPES LA English DT Article ID SYSTEM AB The first experimental investigation has been performed of radiation effects on three-dimensional optical random-access-memory materials. Thin films of poly(methyl methacrylate) doped with spirobenzopyran were irradiated with uniform fluxes of protons, alpha-particles and C-12(+3) ions, at fixed energies per nucleon from 0.5 to 2.5 MeV and fluences from 10(10) to 10(14) cm(-2). The exposed films were examined under a confocal laser scanning microscopy system which is capable of optically sectioning the materials. The irradiation resulted in a permanent change in the materials from a nonfluorescent form to a form which is fluorescent under both 488 and 514 nm excitation. Profiles were measured of fluorescent intensity versus depth, and of intensity versus dose. It was found that both the particle energy and the dose can be obtained from measuring the width of the depth profile and the fluorescent intensity. These properties are very promising for dosimetry applications since they allow calculation of an accurate dose equivalent. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. Georgetown Univ, Med Ctr, Washington, DC 20007 USA. Georgetown Univ, Dept Chem, Washington, DC 20057 USA. USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. RP Phillips, GW (reprint author), USN, Res Lab, 4555 Overlook Ave SW, Washington, DC 20375 USA. NR 13 TC 17 Z9 17 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD MAY PY 1999 VL 50 IS 5 BP 875 EP 881 DI 10.1016/S0969-8043(98)00139-0 PG 7 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 180KG UT WOS:000079384500007 ER PT J AU Shih, A Yater, JE Abrams, R AF Shih, A Yater, JE Abrams, R TI Thermal desorption of Ba from tungsten SO APPLIED SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 2nd International Vacuum Electron Sources Conference 1998 (IVESC 98) CY JUL 07-10, 1998 CL TSUKUBA, JAPAN DE thermionic emission; dispenser cathode; thermal desorption ID LAYER SCANDATE CATHODES; EMISSION AB Scandate cathodes have demonstrated extremely high electron emission densities, and developments are underway to improve the emission uniformity and the replenishment of the active surface layer under ion bombardment. A thorough understanding of the emission mechanism is needed to guide the approach of the development. Much of the surface studies characterize the equilibrated films, and little understanding has been known about the dynamics of the interactions. Some insight into the desorption dynamics can be gained through temperature-programmed desorption studies in which a direct-line-of-sight quadrupole mass analyzer is employed to monitor a specific desorbing atomic or molecular species as a function of the substrate temperature. In this paper, we discuss the experimental method in applying the technique to study Ba/BaO on a tungsten substrate. Multiple adsorption states were observed and each appeared as a distinct desorption feature, from which one is able to determine separately for each state the binding energy, the desorption kinetics and the population. In ascending order of binding energy, we have observed the multilayer Ba adsorption state, Ba-on-W adsorption state, and oxygen-enhanced adsorption state. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. RP Shih, A (reprint author), USN, Res Lab, Code 6844, Washington, DC 20375 USA. NR 12 TC 7 Z9 7 U1 1 U2 3 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 1999 VL 146 IS 1-4 BP 1 EP 6 DI 10.1016/S0169-4332(99)00062-8 PG 6 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 203DJ UT WOS:000080692100002 ER PT J AU Windes, D Dutkowski, J Kaiser, R Justice, R AF Windes, D Dutkowski, J Kaiser, R Justice, R TI Triservice NASA cathode life test facility SO APPLIED SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 2nd International Vacuum Electron Sources Conference 1998 (IVESC 98) CY JUL 07-10, 1998 CL TSUKUBA, JAPAN DE cathode; life; dispenser; reservoir; thermionic emission AB Since December 1992, Naval Surface Warfare Center-Crane Division (NSWCCD) has logged over 1,318,000 h of cathode life testing on 6 different cathode systems in the Triservice/NASA Cathode Life Test Facility. These include two types of reservoir cathodes designated as MK (Siemens), and RV (CPI, formerly Varian), and impregnated matrix cathodes designated M type (manufactured by Semicon and Hughes), TM (Transition Metal cathodes-CPI) and MMM (Mixed Metal Matrix cathodes-CPI). This paper will present results of the cathode life testing at this facility. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USN, Ctr Surface Warfare, Crane Div B3225, Crane, IN 47522 USA. Technol Serv Corp, Santa Monica, CA 90405 USA. RP Windes, D (reprint author), USN, Ctr Surface Warfare, Crane Div B3225, C8065 300 Hwy 361, Crane, IN 47522 USA. NR 1 TC 3 Z9 3 U1 0 U2 1 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 1999 VL 146 IS 1-4 BP 75 EP 78 DI 10.1016/S0169-4332(99)00071-9 PG 4 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 203DJ UT WOS:000080692100013 ER PT J AU Yater, JE Shih, A Abrams, R AF Yater, JE Shih, A Abrams, R TI Cold emission characterization using secondary electron emission spectroscopy SO APPLIED SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 2nd International Vacuum Electron Sources Conference 1998 (IVESC 98) CY JUL 07-10, 1998 CL TSUKUBA, JAPAN DE secondary-electron-emission spectroscopy; cold emission; negative electron affinity (NEA); wide bandgap; diamond; BeO ID BORON-NITRIDE; DIAMOND; AFFINITY; TRANSPORT; SURFACES; CATHODES AB Secondary electron emission spectroscopy is used to study the electron transport and emission properties of wide bandgap materials (e.g., diamond, BeO). The secondary electron distribution generated in diamond is found to be dominated by a high concentration of very low-energy electrons, and the emission characteristics of these low-energy electrons is used to deduce information about the cold emission properties of the material, in particular, analysis of the extremely high yields measured from diamond samples indicates that the low-energy electrons have long escape depths in the material. Furthermore, electron energy distribution measurements provide insight into the emission process at various surfaces. The electron transport and emission model inferred from the diamond measurements suggests that diamond and other wide bandgap materials may be promising cold emitter materials, in which case secondary electron emission spectroscopy can be a useful characterization tool. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. RP Yater, JE (reprint author), USN, Res Lab, Code 6844, Washington, DC 20375 USA. NR 16 TC 1 Z9 1 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 1999 VL 146 IS 1-4 BP 341 EP 346 DI 10.1016/S0169-4332(99)00011-2 PG 6 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 203DJ UT WOS:000080692100059 ER PT J AU Wilhelm, R Beers, TC Sommer-Larsen, J Pier, JR Layden, AC Flynn, C Rossi, S Christensen, PR AF Wilhelm, R Beers, TC Sommer-Larsen, J Pier, JR Layden, AC Flynn, C Rossi, S Christensen, PR TI Spectroscopy of hot stars in the galactic halo. III. Analysis of a large sample of field horizontal-branch and other A-type stars SO ASTRONOMICAL JOURNAL LA English DT Article DE Galaxy : halo; stars : horizontal-branch; stars : Population II ID METAL-POOR STARS; PHOTOELECTRIC UBV PHOTOMETRY; OBJECTIVE-PRISM SURVEY; NORTHERN STARS; SOLAR CIRCLE; DISK STARS; GALAXY; KINEMATICS; ABUNDANCE; SEARCH AB We present results from an analysis of medium-resolution spectroscopy and UBV photometry for a sample of 1121 A-type stars in the halo land disk) of the Galaxy. A previously developed calibration technique is used to assign estimates of effective temperature, surface gravity, and stellar metal abundance, as parameterized by [Fe/H]. Radial velocities are reported with an accuracy of similar to 10 km s(-1). Distance estimates are obtained for the stars with well-determined luminosity classes. Note that although we refer to "A-type" stars, which dominate the present sample, the present data set includes roughly 100 stars of later spectral types, as a result of the temperature range we have chosen to explore in this paper (6000 K less than or equal to T-eff less than or equal to 10,000 K). Included in the hot star sample are 444 stars we classify as held horizontal-branch stars, 416 we classify as main-sequence-gravity A-type (or slightly later) stars (including stars that are likely members of the blue metal-poor population, the so-called BMPs), 140 stars we classify as likely metallic-line (Am) or peculiar (Ap) stars, and 121 stars that cannot be unambiguously classified based on the present data. Examination of the distributions in metallicity and velocity indicates that the field horizontal-branch and main-sequence A-type samples are quite distinct; hence we expect only a modest amount of cross-contamination between the subsamples. We identify 58 RR Lyrae candidates among the hot star sample, based on incompatibilities in their photometric and spectroscopic data. There are 19 stars in the sample that have been previously classified as RR Lyrae variables, and one additional star that had been previously suggested as a variable, though not necessarily of the RR Lyrae class. There are 115 stars in the sample that were previously classified as BMPs by Preston, Beers, & Shectman, most of which fall into the main-sequence A-type category, but 10 of which are found among the Am/Ap classifications. Furthermore, 53 of stars previously considered to be BMPs are shown by our analysis to have metal abundances [Fe/H] > -1, which calls their identification with this population somewhat into question. C1 Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. Univ Copenhagen, Theoret Astrophys Ctr, DK-2100 Copenhagen O, Denmark. USN Observ, Flagstaff Sect, Flagstaff, AZ 86002 USA. Bowling Green State Univ, Dept Phys & Astron, Bowling Green, OH 43403 USA. Tuorla Observ, FIN-21500 Piikkio, Finland. RI Rossi, Silvia/E-9157-2012 OI Rossi, Silvia/0000-0001-7479-5756 NR 45 TC 43 Z9 43 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAY PY 1999 VL 117 IS 5 BP 2329 EP 2380 DI 10.1086/300864 PG 52 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 201XB UT WOS:000080621200027 ER PT J AU Germain, ME Douglass, GG Worley, CE AF Germain, ME Douglass, GG Worley, CE TI Speckle interferometry at the US Naval Observatory. III. SO ASTRONOMICAL JOURNAL LA English DT Article DE binaries : general; binaries : visual; techniques : interferometric ID BINARY STARS AB Position angles and separations resulting from 2578 speckle interferometric observations of 590 binary stars are tabulated. This is the third in a series of papers presenting measures obtained using the 66 cm refractor at the US Naval Observatory in Washington, DC, and covers the period from 1995 June through 1996 December. Program stars range in separation from 0." 2 to 4." 3, with a limiting magnitude of V = 11. Random errors are estimated to be 17.0 mas in separation and 0.degrees 56/rho in position angle, where rho is the separation in arcseconds. These are the first results acquired using an improved intensified CCD detector. The new detector, in concert with an intensity-filtering technique applied in software, has permitted a 1 mag increase in dynamic range, to 3.5 mag, for pairs separated by about 2 ". The instrumentation and calibration are briefly described, with an emphasis on the characteristics of the new detector. The software filter used to increase the dynamic range is also described. C1 USN Observ, NPOI Anderson Mes, Flagstaff, AZ 86001 USA. USN Observ, Washington, DC 20392 USA. RP Germain, ME (reprint author), USN Observ, NPOI Anderson Mes, Flagstaff, AZ 86001 USA. NR 5 TC 13 Z9 13 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAY PY 1999 VL 117 IS 5 BP 2511 EP 2527 DI 10.1086/300859 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 201XB UT WOS:000080621200038 ER PT J AU Laming, JM Drake, JJ AF Laming, JM Drake, JJ TI Stellar coronal abundances. VI. The first ionization potential effect and xi Bootis A - Solar like anomalies at intermediate-activity levels SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : visual; stars : abundances; stars : coronae; ultraviolet : stars ID SPECTRAL-LINE INTENSITIES; ELECTRON-IMPACT EXCITATION; ATOMIC DATA; ELEMENTAL ABUNDANCES; COLLISION STRENGTHS; EUVE OBSERVATIONS; RATE COEFFICIENTS; EPSILON-ERIDANI; COOL STARS; IRON AB Lines from different elements in the Extreme-Ultraviolet Explorer spectra of the corona of the intermediate-activity star xi Bootis A have been analyzed. Assuming that a photospheric composition for the plasma is responsible for the observed coronal emission, emission measures derived from lines of elements with low first ionization potentials (FIPs) are systematically higher than emission measures derived from lines formed at similar temperatures but due to elements with high FIPs. This problem is alleviated by adopting a "coronal" abundance pattern similar to that which appears to characterize the average solar corona. We interpret these results as evidence that the same FIP-based compositional fractionation mechanism at work in the solar outer atmosphere is also operational in the coronae of significantly more active stars such as xi Boo A. C1 SFA Inc, Largo, MD 20774 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Laming, JM (reprint author), SFA Inc, Largo, MD 20774 USA. NR 70 TC 39 Z9 39 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 1999 VL 516 IS 1 BP 324 EP 334 DI 10.1086/307112 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 202NX UT WOS:000080660000029 ER PT J AU Dere, KP Brueckner, GE Howard, RA Michels, DJ Delaboudiniere, JP AF Dere, KP Brueckner, GE Howard, RA Michels, DJ Delaboudiniere, JP TI LASCO and EIT observations of helical structure in coronal mass ejections SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : activity; Sun : corona; Sun : magnetic fields; Sun : particle emission ID LOOP TRANSIENTS; MAGNETIC CLOUDS; SPEEDS AB Observations of coronal mass ejections (CMEs) by the Large Angle Spectrometric Coronagraph (LASCO) on the Solar and Heliospheric Observatory (SOHO) show a significant fraction with circular intensity patterns. In the past, these would have been called "disconnection" events, but we suggest that these are evidence of CMEs containing helical magnetic flux ropes that are often central to many theoretical models of CMEs and have been observed in magnetic clouds near 1 AU. Three examples are examined in detail with the LASCO and Extreme-Ultraviolet Imaging Telescope (EIT) data sets, which provide observations from their initiation through 30 R.. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Univ Paris 11, Inst Astrophys Spatiale, F-91405 Orsay, France. RP Dere, KP (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. NR 23 TC 154 Z9 155 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 1999 VL 516 IS 1 BP 465 EP 474 DI 10.1086/307101 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 202NX UT WOS:000080660000043 ER PT J AU Gherman, RB Browning, J Tramont, J Eggleston, MK AF Gherman, RB Browning, J Tramont, J Eggleston, MK TI Streptococcus viridans intra-amniotic infection associated with antecedent cunnilingus SO AUSTRALIAN & NEW ZEALAND JOURNAL OF OBSTETRICS & GYNAECOLOGY LA English DT Article ID CHORIOAMNIONITIS; CAPNOCYTOPHAGA AB Introduction of bacteria into the amniotic cavity has been associated with oral sex through an ascending infectious route. Previous reports have implicated both Capnocytophaga and Fusobacterium nucleatum via this process. We report a case of Streptococcus viridans intra-amniotic infection occurring at 25 weeks' gestation. Patient questioning revealed a close temporal relationship between the onset of symptoms and previous episodes of cunnilingus. The diagnosis of subclinical bacterial colonization of the amniotic fluid should be considered in patients presenting with preterm labour and no apparent aetiology. A history of recent cunnilingus may be associated with the presence of Streptococcus viridans in the amniotic fluid. C1 USN, Med Ctr, Dept Obstet & Gynecol, Div Maternal Fetal Med, Porthsmouth, VA 23708 USA. RP Gherman, RB (reprint author), Portsmouth Naval Hosp, Dept Obstet & Gynecol, Div Maternal Fetal Med, 620 John Paul Jones Circle, Portsmouth, VA 23708 USA. NR 14 TC 4 Z9 4 U1 0 U2 0 PU AUSTRALIAN NZ J OBSTET GYNAEC PI EAST MELBOURNE PA 254 ALBERT STREET COLLEGE HOUSE, EAST MELBOURNE, VIC 3002, AUSTRALIA SN 0004-8666 J9 AUST NZ J OBSTET GYN JI Aust. N. Z. J. Obstet. Gynaecol. PD MAY PY 1999 VL 39 IS 2 BP 257 EP 259 DI 10.1111/j.1479-828X.1999.tb03388.x PG 3 WC Obstetrics & Gynecology SC Obstetrics & Gynecology GA 206EX UT WOS:000080865300031 PM 10755795 ER PT J AU Kolanko, CJ Pyle, MD Loats, H Parton, J Blakely, WF Nath, J AF Kolanko, CJ Pyle, MD Loats, H Parton, J Blakely, WF Nath, J TI Fast-in situ hybridization and immunoenzymatic color pigment detection of mouse bone marrow micronucleus SO BIOTECHNIC & HISTOCHEMISTRY LA English DT Article DE DNA probe; immunostaining; in situ hybridization; micronucleus ID ERYTHROCYTES; BLOOD AB The development of a whole mouse genomic DNA probe coupled to color pigment painting detection methodology can accurately verify mouse micronuclei induced by chemicals or drugs leading to a lower probability of potential artifacts. Using color pigment painting detection of probes in conjunction with Wright's Giemsa counterstain instead of the current fluorescence detection technology ensures low cost, high resolution permanent documentation of slides for a particular test compound. The permanent color pigment-detected micronuclei and adjoining counterstain allows slides to be stored for future analysis without enhancing the signal or adding antifading agents that are associated with fluorescence detection. Combining innovative technology such as fast-in situ hybridization of DNA probes with immunoenzymatic color pigment detection provides rapid verification of true micronuclei (DNA containing) within 2-3 hr. C1 W Virginia Univ, Genet & Dev Biol Program, Morgantown, WV 26506 USA. USN, Res Lab, Washington, DC 20375 USA. Geocenters Inc, Rockville, MD 20852 USA. Loats Associates Inc, Westminster, MD 21157 USA. Armed Forces Radiobiol Res Inst, Rockville, MD 20855 USA. RP Nath, J (reprint author), W Virginia Univ, Genet & Dev Biol Program, 1120 Agr Sci Bldg, Morgantown, WV 26506 USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1052-0295 J9 BIOTECH HISTOCHEM JI Biotech. Histochem. PD MAY PY 1999 VL 74 IS 3 BP 111 EP 115 DI 10.3109/10520299909047961 PG 5 WC Biotechnology & Applied Microbiology; Cell Biology SC Biotechnology & Applied Microbiology; Cell Biology GA 213FQ UT WOS:000081262400001 PM 10416782 ER PT J AU Harris, VG Pokhil, T AF Harris, VG Pokhil, T TI Evidence for selective resputtering as the growth mechanism of pair-order anisotropy in amorphous TbFe films SO BULLETIN OF MATERIALS SCIENCE LA English DT Article DE magnetic anisotropy; EXAFS; pair-order anisotropy; TbFe films; rf sputter deposition ID ABSORPTION FINE-STRUCTURE; MAGNETIC-ANISOTROPY; FE FILMS; DEPENDENCE AB Processing conditions for rf magnetron sputter-deposited amorphous TbFe films in which an atomic scale structural anisotropy (ASSA) results as a natural consequence of selective resputtering at the film surface during growth are presented. The ASSA, measured using polarization-dependent X-ray absorption fine structure with quantitative modelling via a parametrized nonlinear least squares fitting, is described as a pair order anisotropy (POA) where a statistical preference exists for like atom pairs in-plane and unlike atom pairs perpendicular to the film plane. The perpendicular magnetic anisotropy (PMA) energy increases with increasing POA for samples grown using decreasing rf power and increasing working gas pressure. The POA directly reflects the anisotropic electrostatic environment at the rare earth site which is required for PMA to result from a single ion anisotropy mechanism. C1 USN, Res Lab, Washington, DC 20375 USA. Seagate Technol, Minneapolis, MN 55455 USA. RP Harris, VG (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Harris, Vincent/A-8337-2009 NR 20 TC 2 Z9 2 U1 1 U2 2 PU INDIAN ACADEMY SCIENCES PI BANGALORE PA P B 8005 C V RAMAN AVENUE, BANGALORE 560 080, INDIA SN 0250-4707 J9 B MATER SCI JI Bull. Mat. Sci. PD MAY PY 1999 VL 22 IS 3 BP 503 EP 508 DI 10.1007/BF02749962 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 214EV UT WOS:000081316400051 ER PT J AU Rao, KVSR Markandeyulu, G Suresh, KG Shah, VR Varadaraju, UV Venkatesan, M Huang, MQ Sirisha, K McHenry, ME Harris, VG AF Rao, KVSR Markandeyulu, G Suresh, KG Shah, VR Varadaraju, UV Venkatesan, M Huang, MQ Sirisha, K McHenry, ME Harris, VG TI Recent advances in 2 : 17 and 3 : 29 permanent magnet materials SO BULLETIN OF MATERIALS SCIENCE LA English DT Article DE permanent magnet materials; 2 : 17 compounds; 3 : 29 compounds ID EARTH IRON NITRIDES; RARE-EARTH; NEUTRON-DIFFRACTION; MAGNETOCRYSTALLINE ANISOTROPY; INTERMETALLIC COMPOUNDS; CRYSTAL-STRUCTURE; TERNARY PHASE; FE; ND; NITROGENATION AB The structural and magnetic properties of 2:17 compounds, their nitrides and carbides and the recent development of the novel 3:29 compounds are discussed. C1 Indian Inst Technol, Dept Phys, Mat Sci Res Ctr, Madras 600036, Tamil Nadu, India. Carnegie Mellon Univ, Dept Mat Sci & Engn, Pittsburgh, PA 15213 USA. USN, Res Lab, Washington, DC 20375 USA. RP Rao, KVSR (reprint author), Indian Inst Technol, Dept Phys, Mat Sci Res Ctr, Madras 600036, Tamil Nadu, India. RI Harris, Vincent/A-8337-2009; McHenry, Michael/B-8936-2009 NR 64 TC 5 Z9 5 U1 1 U2 4 PU INDIAN ACADEMY SCIENCES PI BANGALORE PA P B 8005 C V RAMAN AVENUE, BANGALORE 560 080, INDIA SN 0250-4707 J9 B MATER SCI JI Bull. Mat. Sci. PD MAY PY 1999 VL 22 IS 3 BP 509 EP 517 DI 10.1007/BF02749963 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA 214EV UT WOS:000081316400052 ER PT J AU Mendelsohn, J AF Mendelsohn, J TI And it still won't work SO BULLETIN OF THE ATOMIC SCIENTISTS LA English DT Article C1 Arms Control Assoc, Washington, DC USA. RP Mendelsohn, J (reprint author), USN Acad, Annapolis, MD 21402 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU EDUC FOUNDATION NUCLEAR SCI PI CHICAGO PA 6042 SOUTH KIMBARK, CHICAGO, IL 60637 USA SN 0096-3402 J9 B ATOM SCI JI Bull. Atom. Scient. PD MAY-JUN PY 1999 VL 55 IS 3 BP 29 EP 31 PG 3 WC International Relations; Social Issues SC International Relations; Social Issues GA 222YJ UT WOS:000081812700018 ER PT J AU Markowitz, MA Schoen, PE Kust, P Gaber, BP AF Markowitz, MA Schoen, PE Kust, P Gaber, BP TI Surface acidity and basicity of functionalized silica particles SO COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS LA English DT Article DE acidity; basicity; silica particles; functionalized silanes; fluorescence ID GEL AB Tetraethoxysilane has been co-hydrolyzed with functionalized organosilanes in a modified Stober process to produce silica particles with amino, carboxylate or dihydroimidazole groups on the surface. The effects of reaction conditions and the loading of the functionalized organosilane on particle size was examined by TEM. Fluorescence spectroscopy of the surface amino groups covalently modified with fluorescamine, and the surface carboxylate groups with 4-bromomethyl-6,7-dimethoxycoumarin, demonstrated that these functional groups were accessible for further reaction. Changes in surface acidity and basicity caused by the presence of functional groups (amine, dihydroimidazole, carboxylate) on the particle surface were determined using an indicator titration technique. Particles with surface imidazole and amine groups and particles with surface carboxylate groups have enhanced basicity and acidity, respectively. Dihydroimidazole-modified silica had greater surface basicity than the amine-modified silica. The effect on basicity and acidity increases as the amount of added functionalized silane increases. However, this increase is nonlinear with respect to the increase in added functionalized silane. Particles with both surface dihydroimidazole and carboxylate groups demonstrated reduced surface basicity and acidity. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Ctr Biomol Sci & Engn, Lab Mol Interfacial Interact, Washington, DC 20375 USA. RP Markowitz, MA (reprint author), USN, Res Lab, Ctr Biomol Sci & Engn, Lab Mol Interfacial Interact, Code 6930, Washington, DC 20375 USA. EM mam@cbmse.nrl.navy.mil NR 26 TC 23 Z9 25 U1 0 U2 14 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-7757 J9 COLLOID SURFACE A JI Colloid Surf. A-Physicochem. Eng. Asp. PD MAY 1 PY 1999 VL 150 IS 1-3 BP 85 EP 94 DI 10.1016/S0927-7757(98)00715-8 PG 10 WC Chemistry, Physical SC Chemistry GA 181WB UT WOS:000079464900010 ER PT J AU Oser, RL Gualtieri, JW Cannon-Bowers, JA Salas, E AF Oser, RL Gualtieri, JW Cannon-Bowers, JA Salas, E TI Training team problem solving skills: an event-based approach SO COMPUTERS IN HUMAN BEHAVIOR LA English DT Article DE teams; team training; problem solving; instructional strategies; scenario design ID GROUP DECISION-MAKING; EXPERTISE; MODEL AB Training problem solving teams presents a unique set of challenges to instructional designers. Given the criticality of teams to the performance of many organizations, it is important to develop training systems to support coordination and problem solving. While recent technological advancements, such as computer-based performance assessment, hold considerable promise for training, the introduction of technology alone does not guarantee that the training will be effective. This article focuses on three important questions that must be addressed when developing coordination and problem solving training: (1) How can technology best be used to provide an environment in which learning can take place? (2) What knowledge, skills, and attitudes need to be learned and trained to facilitate expert problem solving teams? and (3) How can the development of problem solving expertise be fostered through a systematic instructional strategy? A naturalistic decision making paradigm will be used to provide a theoretical framework for describing the problem solving task domain. An event-based approach to training will then be offered as a practical application for training teams to perform in naturalistic environments. Finally, conclusions are drawn regarding the provided framework for team learning. Published by Elsevier Science Ltd. C1 USN, Air Warfare Ctr, Training Syst Div, Orlando, FL 32826 USA. RP Salas, E (reprint author), USN, Air Warfare Ctr, Training Syst Div, 12350 Res Pkwy, Orlando, FL 32826 USA. OI Cannon-Bowers, Janis/0000-0003-2154-4456 NR 68 TC 18 Z9 21 U1 0 U2 8 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0747-5632 J9 COMPUT HUM BEHAV JI Comput. Hum. Behav. PD MAY-JUL PY 1999 VL 15 IS 3-4 BP 441 EP 462 DI 10.1016/S0747-5632(99)00031-X PG 22 WC Psychology, Multidisciplinary; Psychology, Experimental SC Psychology GA 205KA UT WOS:000080818800010 ER PT J AU Trzaskoma-Paulette, PP Lambrakos, SG Jones, HN AF Trzaskoma-Paulette, PP Lambrakos, SG Jones, HN TI Closed-cell polymer foams for corrosion control in confined metal spaces SO CORROSION LA English DT Article DE automotive industry; cavities; marine applications and environments; polymers and polymer coatings; retrofit; seawater; steel AB The use of closed-cell plastic polymer foams to control corrosion in hollow, Irregular cavities of preexisting metallic structures or assemblages was explored The method involved blocking the access of corrosive species to the interior surfaces by filling the empty spaces with an expanding, polymeric, rigid foam material The fact that the foam could be injected from a remote location and then expanded to fill the void solved the problem of accessibility, which precluded the use of traditional corrosion preventive coatings in these areas. The approach differed from prior studies in that it focused on postdesign applications of corrosion inhibition within confined regions. Results of laboratory seawater exposure tests using structural steel tubular specimens with interior surfaces that were as-manufactured, precorroded, or protected with a paraffin-based corrosion preventative and filled with a one-part polyurethane foam were discussed in the context of the foam's ability to prevent water penetration to the metal interface. Effectiveness of the method for corrosion control was demonstrated through visual comparisons of metal deterioration In treated and untreated specimens. C1 USN, Res Lab, Div Mat & Technol, Washington, DC 20375 USA. RP Trzaskoma-Paulette, PP (reprint author), USN, Res Lab, Div Mat & Technol, Code 6310-2, Washington, DC 20375 USA. NR 9 TC 2 Z9 2 U1 0 U2 3 PU NATL ASSN CORROSION ENG PI HOUSTON PA 1440 SOUTH CREEK DRIVE, HOUSTON, TX 77084-4906 USA SN 0010-9312 J9 CORROSION JI Corrosion PD MAY PY 1999 VL 55 IS 5 BP 530 EP 539 PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 196ZN UT WOS:000080340300012 ER PT J AU Gray, GC Callahan, JD Hawksworth, AW Fisher, CA Gaydos, JC AF Gray, GC Callahan, JD Hawksworth, AW Fisher, CA Gaydos, JC TI Respiratory diseases among US military personnel: Countering emerging threats SO EMERGING INFECTIOUS DISEASES LA English DT Article ID STREPTOCOCCUS-PYOGENES INFECTION; GLOBAL INFLUENZA SURVEILLANCE; ACUTE RHEUMATIC-FEVER; SHOCK-LIKE SYNDROME; UNITED-STATES; MARINE-CORPS; MYCOPLASMA-PNEUMONIAE; ARMY TRAINEES; RISK-FACTORS; PENICILLIN-G AB Emerging respiratory disease agents, increased antibiotic resistance, and the loss of effective vaccines threaten to increase the incidence of respiratory disease in military personnel. We examine six respiratory pathogens (adenoviruses, influenza viruses, Streptococcus pneumoniae, Streptococcus pyogenes, Mycoplasma pneumoniae, and Bordetella pertussis) and review the impact of the diseases they cause, past efforts to control these diseases in U.S. military personnel, as well as current treatment and surveillance strategies, limitations in diagnostic testing, and vaccine needs. C1 Naval Hlth Res Ctr, Emerging Illness Div, San Diego, CA 92186 USA. Naval Med Ctr, San Diego, CA USA. Walter Reed Army Med Ctr, Walter Reed Army Inst Res, Washington, DC 20307 USA. RP Gray, GC (reprint author), Naval Hlth Res Ctr, Emerging Illness Div, POB 85122, San Diego, CA 92186 USA. NR 80 TC 149 Z9 156 U1 1 U2 7 PU CENTER DISEASE CONTROL PI ATLANTA PA ATLANTA, GA 30333 USA SN 1080-6040 J9 EMERG INFECT DIS JI Emerg. Infect. Dis PD MAY-JUN PY 1999 VL 5 IS 3 BP 379 EP 387 PG 9 WC Immunology; Infectious Diseases SC Immunology; Infectious Diseases GA 205NN UT WOS:000080827600008 PM 10341174 ER PT J AU Chung, HS Chen, CSH Kremer, RA Boulton, JR Burdette, GW AF Chung, HS Chen, CSH Kremer, RA Boulton, JR Burdette, GW TI Recent developments in high-energy density liquid hydrocarbon fuels SO ENERGY & FUELS LA English DT Article AB The evolution of high-energy density fuels over the past three decades is briefly described. This period can be characterized by exceedingly slow progress and notable lack of success toward the development of practical, economically viable fuel systems. Recently, two novel ultrahigh-energy density fuels, one naturally occurring and one synthetic, have emerged; these fuels, which are both composed of compact hydrocarbon molecules, have energy contents or heating values significantly greater than that of currently used standard missile fuel JP-10 (up to 160K Btu/gal (44.7K MJ/m(3)) vs 141.7K Btu/gal (39.6K MJ/m(3))). In addition, these fuels also exhibit superior low-temperature, viscometric, flash-point, and other properties that are desired and, indeed, required for practical fuels. Initial research and development of these fuels are described, and their chemistries, properties, and, in the case of the naturally occurring fuel, engine test results are provided. C1 Mobil Technol Co, Paulsboro, NJ 08066 USA. USN, Ctr Weap, Weapons Div, China Lake, CA 93555 USA. RP Chung, HS (reprint author), Interlink Technol Inc, 2 Michael Way, Pennington, NJ 08534 USA. NR 24 TC 90 Z9 121 U1 4 U2 29 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD MAY-JUN PY 1999 VL 13 IS 3 BP 641 EP 649 DI 10.1021/ef980195k PG 9 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA 197YD UT WOS:000080393200014 ER PT J AU Wang, YM Sheeley, NR Howard, RA St Cyr, OC Simnett, GM AF Wang, YM Sheeley, NR Howard, RA St Cyr, OC Simnett, GM TI Coronagraph observations of inflows during high solar activity SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MASS EJECTIONS; ORIGIN; LASCO AB Since the start of the SOHO mission three years ago, the Large Angle Spectrometric Coronagraph (LASCO) has recorded numerous examples of small, faint features moving inward through the corona. The inflows are observed at heliocentric distances of 2-4 R-S and became increasingly common during 1998, as solar and coronal mass ejection (CME) activity increased. The inward-moving structures, which are most easily detected in running difference movies, often have a cusplike appearance and tend to leave a density depletion in their wake; the downward velocities range from less than 20 km s(-1) to over 100 km s(-1). The downflows are observed typically similar to 1 day after the passage of a CME, and coexist side by side with continuing outflows of streamer material. We interpret these small-scale events as observational signatures of the gradual closing-down of magnetic flux dragged outward by CMEs or other transient outflows. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Univ Birmingham, Sch Phys & Space Res, Birmingham B15 2TT, W Midlands, England. Computat Phys Inc, Fairfax, VA USA. RP Wang, YM (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. NR 10 TC 56 Z9 56 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 1 PY 1999 VL 26 IS 9 BP 1203 EP 1206 DI 10.1029/1999GL900209 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 193EL UT WOS:000080122900005 ER PT J AU Sperber, KR AF Sperber, KR CA Participating AMIP Modelling Grp TI Are revised models better models? A skill score assessment of regional interannual variability SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID INTERCOMPARISON PROJECT; MONSOON; AMIP; PRECIPITATION; SENSITIVITY; RAINFALL; GCM AB Various skill scores are used to assess the performance of revised models relative to their original configurations. The interannual variability of all-India, Sahel and Nordeste rainfall and summer monsoon windshear is examined in integrations performed under the experimental design of the Atmospheric Model Intercomparison Project. For the indices considered, the revised models exhibit greater fidelity at simulating the observed interannual variability. Interannual variability of all-India rainfall is better simulated by models that have a more realistic rainfall climatology in the vicinity of India, indicating the beneficial effect of reducing systematic model error. C1 Univ Calif Lawrence Livermore Natl Lab, PCMDI, Livermore, CA 94550 USA. Res Ctr, Bur Meteorol, Melbourne, Vic, Australia. Ctr Natl Rech Meteorol, Toulouse, France. Dept Numer Math, Moscow, Russia. DERF, Geophys Fluid Dynam Lab, Princeton, NJ USA. Meteorol Dynam Lab, Paris, France. Max Planck Inst Meteorol, Hamburg, Germany. Meteorol Res Inst, Tsukuba, Ibaraki 305, Japan. USN, Res Lab, Monterey, CA USA. SUNY Albany, SNG, Albany, NY 12222 USA. Yonsei Univ, Seoul 120749, South Korea. RP Sperber, KR (reprint author), Univ Calif Lawrence Livermore Natl Lab, PCMDI, POB 808,L-264, Livermore, CA 94550 USA. RI Sperber, Kenneth/H-2333-2012 NR 23 TC 17 Z9 17 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 1 PY 1999 VL 26 IS 9 BP 1267 EP 1270 DI 10.1029/1999GL900227 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 193EL UT WOS:000080122900021 ER PT J AU Fujimura, K Kuo, E AF Fujimura, K Kuo, E TI Shape reconstruction from contours using isotopic deformation SO GRAPHICAL MODELS AND IMAGE PROCESSING LA English DT Article DE shape reconstruction; terrain modeling; isosurface; deformation ID PLANAR CROSS-SECTIONS; SURFACE RECONSTRUCTION; INTERPOLATION TECHNIQUE; SLICES; TRIANGULATION AB A method for shape reconstruction from contours using isotopic deformation is presented. The proposed method considers the case where one contour encloses the other contour when they are projected in a common plane, as is the case for terrain contour maps. Unlike many other methods which generate piecewise linear interpolation, the proposed method smoothly interpolates between two contours located in parallel planes. The algorithm runs in O(nk + n log n) time, where n is the total number of vertices in two contours and k is an integer variable less than n which indicates how convoluted the contours are (the larger, the more convoluted). The running time of the algorithm is shown to be worst-case optimal for the class of task defined. The reconstructed shape is free of self-intersections and it can incorporate given feature correspondences. The method is extended to handle bifurcations and is shown to cope easily with some cases which are problematic for some other algorithms, The method proposed is suitable for terrain modeling, since reconstructed shapes generated by the method do not have overhangs. Experimental results are included to illustrate the feasibility of the approach. (C) 1999 Academic Press. C1 Ohio State Univ, Dept Comp & Informat Sci, Columbus, OH 43210 USA. USN, Res Lab, Washington, DC 20375 USA. RP Ohio State Univ, Dept Comp & Informat Sci, 2015 Neil Ave, Columbus, OH 43210 USA. EM fujimura@cis.ohio-state.edu NR 34 TC 6 Z9 8 U1 0 U2 0 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1077-3169 J9 GRAPH MODEL IM PROC JI Graph. Models Image Process. PD MAY PY 1999 VL 61 IS 3 BP 127 EP 147 DI 10.1006/gmip.1999.0494 PG 21 WC Computer Science, Software Engineering SC Computer Science GA 227YG UT WOS:000082107100001 ER PT J AU Felli, JC Hazen, GB AF Felli, JC Hazen, GB TI A Bayesian approach to sensitivity analysis SO HEALTH ECONOMICS LA English DT Article DE Bayesian decision theory; the value of information; economics of information; statistical methods ID MINIMAL IMPORTANT DIFFERENCE; DECISION-ANALYSIS; HEALTH-CARE AB Sensitivity analysis has traditionally been applied to decision models to quantify the stability of a preferred alternative to parametric variation. In the health literature, sensitivity measures have traditionally been based upon distance metrics, payoff variations, and probability measures. We advocate a new approach based on information value and argue that such an approach is better suited to address the decision-maker's real concerns. We provide an example comparing conventional sensitivity analysis to one based on information value. This article is a US government work and is in the public domain in the United States. C1 USN, Postgrad Sch, Monterey, CA 93943 USA. Northwestern Univ, Evanston, IL USA. RP Felli, JC (reprint author), USN, Postgrad Sch, DRMI Code 64 FL,1522 Cunningham Rd, Monterey, CA 93943 USA. RI Hazen, Gordon/B-7463-2009 NR 18 TC 33 Z9 33 U1 0 U2 4 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1057-9230 J9 HEALTH ECON JI Health Econ. PD MAY PY 1999 VL 8 IS 3 BP 263 EP 268 DI 10.1002/(SICI)1099-1050(199905)8:3<263::AID-HEC426>3.0.CO;2-S PG 6 WC Economics; Health Care Sciences & Services; Health Policy & Services SC Business & Economics; Health Care Sciences & Services GA 195BQ UT WOS:000080229600009 PM 10348421 ER PT J AU Shinn, JL Wilson, JW Singleterry, RC Xapsos, MA AF Shinn, JL Wilson, JW Singleterry, RC Xapsos, MA TI Implication of microdosimetry in estimation of radiation quality in space environment SO HEALTH PHYSICS LA English DT Article DE microdosimetry; lineal energy; quality factor; proportional counters ID ENERGY DEPOSITION; IONIZATION; SITES; DISTRIBUTIONS; FLUCTUATIONS; SPECTRA; MODEL AB Errors introduced using a tissue equivalent proportional counter to estimate radiation quality of an arbitrary ion field as related to space radiations are examined. This is accomplished by using a generalized analytic model to calculate the effect of energy loss straggling, track structure, and pathlength distribution on the microdosimetric distribution, The error can be as large as a factor of two, but no systematic trend could be found. C1 NASA, Langley Res Ctr, Div Mat, Hampton, VA 23681 USA. USN, Res Lab, Washington, DC 20375 USA. NR 36 TC 3 Z9 3 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD MAY PY 1999 VL 76 IS 5 BP 510 EP 515 DI 10.1097/00004032-199905000-00007 PG 6 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 184AZ UT WOS:000079588300006 PM 10201564 ER PT J AU Kluskens, MS AF Kluskens, MS TI A new algorithm for the complex exponential integral in the method of moments SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE method of moments ID MUTUAL IMPEDANCE; ARGUMENT; DIPOLES; WIRE AB This paper presents a new algorithm for the rapid and accurate calculation of the complex exponential integral associated with the mutual impedance of sinusoidal basis and testing functions in the method of moments. The new algorithm uses Leibniz's theorem to calculate Taylor series expansions of the integral instead of integrating expansions of the integrand as is often done. This results in an algorithm which is twice as fast as and is valid over a wider range than previous algorithms. This technique can be applied to many other integrals encountered in computational electromagnetics as well. C1 USN, Res Lab, Washington, DC 20375 USA. RP Kluskens, MS (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 23 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 USA SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD MAY PY 1999 VL 47 IS 5 BP 803 EP 806 DI 10.1109/8.774133 PG 4 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 214HF UT WOS:000081322000005 ER PT J AU Borden, B AF Borden, B TI Reduction of radar image artifacts caused by target inlets SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE inlets; radar cross section; radar imaging ID SCATTERING; RCS AB The standard radar weak-scatterer model is inappropriate to targets with inlets and cavities and range-resolved images created using this model often display artifacts associated with these structures. Since inlets and cavities (typically) make a strong contribution to the radar field scattered from aircraft targets, these artifacts can confound the image interpretation process. Many of the more complete and accurate scattering models require extensive knowledge about the cavity/inlet shape and size and, moreover, are numerically intensive-features that make them unsuitable for many imaging applications. We examine an older (first-order) model based on a weak-scattering modal expansion of the structure which appears to be well suited to radar imaging. C1 USN, Air Warfare Ctr, Weapons Div, Res & Technol Grp, China Lake, CA 93555 USA. RP Borden, B (reprint author), USN, Air Warfare Ctr, Weapons Div, Res & Technol Grp, China Lake, CA 93555 USA. NR 14 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 USA SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD MAY PY 1999 VL 47 IS 5 BP 898 EP 901 DI 10.1109/8.774154 PG 4 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 214HF UT WOS:000081322000018 ER PT J AU Jackson, RH AF Jackson, RH TI Off-axis expansion solution of Laplace's equation: Application to accurate and rapid calculation of coil magnetic fields SO IEEE TRANSACTIONS ON ELECTRON DEVICES LA English DT Article DE accelerator magnets; algorithm; coils; electromagnets; electron optics; electron tubes; magnetic and electric fields; permanent magnets; simulation; solenoids AB A flexible algorithm for the accurate computation of off-axis magnetic fields of coils in cylindrical geometry is presented. The method employs a partial power series decomposition of Laplace's equation about the symmetry axis where the series coefficients are derivatives of the field along the axis. A method for computing high order analytic derivatives for four "basic" coil types (loop, annular disk, thin solenoid, and full coil) will be demonstrated. Utilizing these derivatives, highly accurate off-axis fields can be calculated for the basic coil types. For ideal current loops, field errors of less than 0.1% of the exact elliptic integral solution can be obtained out to approximately 70% of the loop radius. Accuracy improves substantially near the symmetry axis and is higher than normally achievable with mesh-based or integral solvers. The simplicity, compactness and speed of this method make it a good adjunct to other techniques and ideal as a module for incorporation into more general programs. C1 USN, Res Lab, Vacuum Elect Branch, Washington, DC 20375 USA. RP Jackson, RH (reprint author), Lucent Technol, Norcross, GA 30071 USA. NR 14 TC 14 Z9 17 U1 1 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9383 J9 IEEE T ELECTRON DEV JI IEEE Trans. Electron Devices PD MAY PY 1999 VL 46 IS 5 BP 1050 EP 1062 DI 10.1109/16.760416 PG 13 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 190JT UT WOS:000079960000032 ER PT J AU Ramos, A Smith, RM Gates, W Adams, SK Rodier, D Guerrero, JCA Hunt, C Tanner, G AF Ramos, A Smith, RM Gates, W Adams, SK Rodier, D Guerrero, JCA Hunt, C Tanner, G TI Round table on industrial engineering SO IIE SOLUTIONS LA English DT Editorial Material C1 USN, Coastal Syst Stn, Panama City, FL USA. Pretty Prod Inc, Coshocton, OH 43810 USA. Huntsman, Port Neches, TX 77651 USA. Iowa State Univ, Dept Ind & Mfg Syst Engn, Ames, IA 50011 USA. Key Plast LLC, Howell, MI 48843 USA. Deacero SA CV, Monterrey, Mexico. RPS Inc, Shawnee, KS USA. Logistix, Fremont, CA USA. RP Ramos, A (reprint author), USN, Coastal Syst Stn, Panama City, FL USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INST INDUSTRIAL ENGINEERS PI NORCROSS PA 25 TECHNOLOGY PARK/ATLANTA, NORCROSS, GA 30092 USA SN 1085-1259 J9 IIE SOLUTIONS JI IIE Solut. PD MAY PY 1999 VL 31 IS 5 BP 82 EP 82 PG 1 WC Engineering, Industrial SC Engineering GA 201DP UT WOS:000080580000025 ER PT J AU Todd, MD Vohra, ST AF Todd, MD Vohra, ST TI An alternative approach to Poincare sectioning in weakly nonlinear systems SO INTERNATIONAL JOURNAL OF BIFURCATION AND CHAOS LA English DT Article ID SPHERICAL PENDULUM; MODULATED MOTIONS; EXPONENTS AB A large array of dynamical systems can be broadly classified as weakly nonlinear, where a common feature is the presence of dual time-scale dynamics. Often it is desirable to isolate the dynamics at one time scale (typically the slower time scale), and this paper presents a generic phase-sensitive detection method that successfully isolates the slow-time dynamics, stripping off the less-relevant and often dominant fast-time dynamics. We shall also show for the first time, under certain phase considerations, the equivalence of the present method and the traditional Poincare section of the original full response. The method is first presented in theory and then applied to data from a numerical simulation of the forced spherical pendulum followed by data from a similar spherical pendulum experiment. The method is successful provided certain conditions apply for phase stationarity. C1 USN, Res Lab, Washington, DC 20375 USA. RP Todd, MD (reprint author), USN, Res Lab, Code 5670, Washington, DC 20375 USA. NR 19 TC 2 Z9 2 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0218-1274 J9 INT J BIFURCAT CHAOS JI Int. J. Bifurcation Chaos PD MAY PY 1999 VL 9 IS 5 BP 953 EP 962 DI 10.1142/S0218127499000687 PG 10 WC Mathematics, Interdisciplinary Applications; Multidisciplinary Sciences SC Mathematics; Science & Technology - Other Topics GA 228NZ UT WOS:000082143700013 ER PT J AU Robinson, GE AF Robinson, GE TI From occupation to interim accords: Israel and the Palestinian territories SO INTERNATIONAL JOURNAL OF MIDDLE EAST STUDIES LA English DT Book Review C1 USN, Postgrad Sch, Monterey, CA 93940 USA. RP Robinson, GE (reprint author), USN, Postgrad Sch, Monterey, CA 93940 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0020-7438 J9 INT J MIDDLE E STUD JI Int. J. Middle East Stud. PD MAY PY 1999 VL 31 IS 2 BP 314 EP 317 PG 4 WC Area Studies SC Area Studies GA 196WA UT WOS:000080330000031 ER PT J AU Schlaf, R Pettenkofer, C Jaegermann, W AF Schlaf, R Pettenkofer, C Jaegermann, W TI Band lineup of a SnS2/SnSe2/SnS2 semiconductor quantum well structure prepared by van der Waals epitaxy SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MOLECULAR-BEAM EPITAXY; ABSORPTION-EDGE; SINGLE-CRYSTAL; SNSE2; HETEROJUNCTIONS; PHOTOVOLTAGE; INTERFACES; DIPOLES AB A quantum well composed of layered semiconductors and SnSe2 (E-g = 1.03 eV) and SnS2 (E-g = 2.18 eV) was grown in several steps by van der Waals epitaxy. After each growth step the electronic structure was characterized by ultraviolet and x-ray photoemission spectroscopy. From these measurements, bandbending and the valence-band offset were determined on both sides of the quantum well. The results show that both wells are of the same magnitude, hence indicating commutativity of the band offset. Small interface dipoles (0.11-0.19 eV) were detected at the interfaces, which could be identified as quantum dipoles. (C) 1999 American Institute of Physics. [S0021-8979(99)03409-X]. C1 Hahn Meitner Inst Kernforsch Berlin GmbH, Bereich CG, D-14109 Berlin, Germany. RP Schlaf, R (reprint author), USN, Res Lab, Code 5615,4555 Overlook Ave, Washington, DC 20375 USA. NR 29 TC 16 Z9 16 U1 4 U2 32 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 1999 VL 85 IS 9 BP 6550 EP 6556 DI 10.1063/1.370160 PG 7 WC Physics, Applied SC Physics GA 188WA UT WOS:000079871200041 ER PT J AU Broussard, PR Qadri, SB Browning, VM Cestone, VC AF Broussard, PR Qadri, SB Browning, VM Cestone, VC TI Characterization of transport and magnetic properties in thin film La-0.67(CaxSr1-x)(0.33) MnO3 mixtures SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ELECTRICAL-TRANSPORT; MAGNETORESISTANCE; LA0.67CA0.33MNO3; PEROVSKITES; EXCHANGE; OXIDES AB We have grown thin films of (100)-oriented La-0.67(CaxSr1-x)(0.33)MnO3 on (100) NdGaO3 substrates by off-axis sputtering. We have looked at the changes in the resistivity and magnetoresistance of the samples as the Ca/Sr ratio was varied. We find that as the calcium fraction is decreased, the lattice match to the substrate decreases, and the films become more disordered, as observed in transport measurements and the variation in Curie and peak resistance temperatures. We find a correlation between the temperature independent and T-2 terms to the low temperature resistivity. The room temperature magnetoresistance exhibits a maximum as the peak temperature is increased by the substitution of Sr for Ca, and a change in the field dependence to the resistivity at room temperature is observed. [S0021-8979(99)03209-0]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Broussard, PR (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 15 TC 14 Z9 15 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 1999 VL 85 IS 9 BP 6563 EP 6566 DI 10.1063/1.370162 PG 4 WC Physics, Applied SC Physics GA 188WA UT WOS:000079871200043 ER PT J AU Mrstik, BJ Afanas'ev, VV Stesmans, A McMarr, PJ Lawrence, RK AF Mrstik, BJ Afanas'ev, VV Stesmans, A McMarr, PJ Lawrence, RK TI Relationship between oxide density and charge trapping in SiO2 films SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID VACUUM-ULTRAVIOLET IRRADIATION; ELECTRON-SPIN-RESONANCE; SILICON DIOXIDE; SPECTROSCOPIC ELLIPSOMETRY; (111)SI/SIO2 INTERFACE; STRUCTURAL RELAXATION; RADIATION RESPONSE; THIN SIO2-FILMS; THERMAL OXIDES; 100 SILICON AB Spectroscopic ellipsometry was used to determine the density of oxides thermally grown on Si substrates as a function of the oxidation temperature, and the time and temperature of postoxidation anneals. All the oxides were found to be denser than fused silica. The density of the as-grown oxides was found to decrease as the growth temperature was increased. Postoxidation anneals were found to reduce the oxide density; high temperature or long-time anneals caused the greatest reduction in density. Holes alone, or holes and electrons, were injected into the oxides by irradiating with vacuum ultraviolet light or x rays under electric field bias. Using capacitance-voltage measurements, it was found that low-density oxides trap charge more efficiently than high-density oxides. Electron spin resonance measurements indicated that, for most of these oxides, the number of paramagnetic defects was substantially smaller than the number of trapped charges. It is hypothesized that the additional, nonparamagnetic, charge is in the form of protons trapped near network oxygen atoms that have large Si-O-Si bond angles. The number of these large-angle bonds in the near-interfacial oxide increases as the oxide density decreases, explaining the observed correlation between the charge trapping and the oxide density. (C) 1999 American Institute of Physics. [S0021-8979(99)06809-7]. C1 USN, Res Lab, Washington, DC 20375 USA. Katholieke Univ Leuven, Dept Phys, B-3001 Louvain, Belgium. Aracor, Washington, DC 20375 USA. RP Mrstik, BJ (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 54 TC 48 Z9 50 U1 1 U2 11 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 1999 VL 85 IS 9 BP 6577 EP 6588 DI 10.1063/1.370164 PG 12 WC Physics, Applied SC Physics GA 188WA UT WOS:000079871200046 ER PT J AU Yang, MJ Moore, WJ Yang, CH Wilson, RA Bennett, BR Shanabrook, BV AF Yang, MJ Moore, WJ Yang, CH Wilson, RA Bennett, BR Shanabrook, BV TI Determination of temperature dependence of GaSb absorption edge and its application for transmission thermometry SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID BEAM-EPITAXIAL-GROWTH; ALSB/INAS HEMTS; INAS; DETECTOR; LASERS; ALSB AB Transmission spectra of GaSb have been obtained over a temperature range from 10 to 470 degrees C. Using this information, transmission thermometry is applied to obtain accurate measurements of sample temperature during molecular beam epitaxy growth on GaSb substrates. A GaSb surface reconstruction transition is determined as a function of Sb flux and substrate temperature, establishing a laboratory-independent temperature standard. (C) 1999 American Institute of Physics. [S0021-8979(99)06707-9]. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Maryland, Dept Elect Engn, College Pk, MD 20742 USA. Lab Phys Sci, College Pk, MD 20742 USA. 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 22 TC 19 Z9 19 U1 0 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 1999 VL 85 IS 9 BP 6632 EP 6635 DI 10.1063/1.370290 PG 4 WC Physics, Applied SC Physics GA 188WA UT WOS:000079871200054 ER PT J AU Storm, DF Lange, MD Cole, TL AF Storm, DF Lange, MD Cole, TL TI Surfactant effects of thallium in the epitaxial growth of indium arsenide on gallium arsenide(001) SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MOLECULAR-BEAM EPITAXY; INAS/GAAS QUANTUM DOTS; SELF-ORGANIZED GROWTH; GAAS 001; INAS; LAYERS; TEMPERATURE; INXGA1-XAS; ALLOYS; WELLS AB We report on the role of thallium as a surfactant in the growth of InAs on GaAs(001) by molecular beam epitaxy. Thallium suppresses the transition from two-dimensional to three-dimensional growth modes for temperatures below 440 degrees C without incorporating significantly into the bulk InAs lattice. It extends the range of temperatures at which InAs may be grown, and appears to improve the crystalline quality of growth at 520 degrees C. Preliminary results indicate that at low temperature (280 degrees C) thallium does not prolong pseudomorphic growth beyond the normal critical layer thickness, but rather may form interfacial InTlAs with a greater concentration of thallium than has been achieved to date. (C) 1999 American Institute of Physics. [S0021-8979(99)07409-5]. C1 USN, Air Warfare Ctr, Weap Div, Phys Branch,Res & Technol Grp, China Lake, CA 93555 USA. RP Storm, DF (reprint author), USN, Air Warfare Ctr, Weap Div, Phys Branch,Res & Technol Grp, China Lake, CA 93555 USA. NR 30 TC 10 Z9 10 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 1999 VL 85 IS 9 BP 6838 EP 6842 DI 10.1063/1.370292 PG 5 WC Physics, Applied SC Physics GA 188WA UT WOS:000079871200088 ER PT J AU Cummings, RJ Loveless, EA Mazur, JM Campbell, J Samelson, S AF Cummings, RJ Loveless, EA Mazur, JM Campbell, J Samelson, S TI Untitled - Reply SO JOURNAL OF BONE AND JOINT SURGERY-AMERICAN VOLUME LA English DT Letter C1 Nemours Childrens Clin, Jacksonville, FL 32207 USA. USN Hosp, Dept Orthopaed, Camp Le Jeune, NC 28547 USA. 42nd Med Grp, SGSO, Maxwell AFB, AL 36112 USA. RP Cummings, RJ (reprint author), Nemours Childrens Clin, 807 Nira St, Jacksonville, FL 32207 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU JOURNAL BONE JOINT SURGERY INC PI NEEDHAM PA 20 PICKERING ST, NEEDHAM, MA 02192 USA SN 0021-9355 J9 J BONE JOINT SURG AM JI J. Bone Joint Surg.-Am. Vol. PD MAY PY 1999 VL 81A IS 5 BP 744 EP 744 PG 1 WC Orthopedics; Surgery SC Orthopedics; Surgery GA 198FR UT WOS:000080412800025 ER PT J AU Cortazar, P Johnson, BE AF Cortazar, P Johnson, BE TI Review of the efficacy of individualized chemotherapy selected by in vitro drug sensitivity testing for patients with cancer SO JOURNAL OF CLINICAL ONCOLOGY LA English DT Review ID CELL LUNG-CANCER; PROSPECTIVE CLINICAL-TRIAL; METASTATIC BREAST-CANCER; SUBRENAL CAPSULE ASSAY; TUMOR STEM-CELLS; PHASE-II TRIAL; OVARIAN-CANCER; ANTHRACYCLINE-RESISTANT; COLORIMETRIC ASSAY; MTT ASSAY AB Purpose: The purpose of this study is to review the potential efficacy of individualized chemotherapy selected by in vitro drug sensitivity testing (DST) compared with empiric regimens for patients with cancer. Methods: MEDLINE and CANCERLIT were searched for articles published tin English) about prospective clinical trials in which patients were treated with chemotherapy that was selected with the use of in vitro DST. Results: We identified 12 prospective studies that examined the benefit of chemotherapy selected by DST. Five hundred six patients (33%) were treated with chemotherapy that was selected with the use of in vitro DST. The mean response rate for patients treated with in vitro-selected therapy was 27% (range, 10% to 100%; 12 studies) compared with 18% (range, 0% to 100%; n = 7 studies) for patients treated with empiric therapy Five studies (only one randomized) evaluated the impact of chemotherapy selected by in vitro DST on patient survival. Three studies showed that survival was 1 to 4 months longer for the 238 patients treated with empiric chemotherapy compared with that of the 65 patients treated with chemotherapy that wets selected by in vitro testing. Two nonrandomized studies showed that survival wets 4 or 19 months longer for 27 patients treated with chemotherapy selected by in vitro testing compared with that of 80 patients who were treated with empiric chemotherapy. Conclusion: Only one third of patients entered in prospective trials of in vitro DST were actually treated with an in vitro best regimen. The response rates seem to be better with in vitro selected chemotherapy regimens than with empiric regimens, but the impact on survival has not been adequately addressed. J Clin Oncol 17:1625-1631. (C) 1999 by American Society of Clinical Oncology. C1 NCI, Lung Canc Biol Sect, Med Branch, USN,Div Clin Sci, Bethesda, MD 20892 USA. RP Johnson, BE (reprint author), Dana Farber Canc Inst, Lowe Ctr Thorac Oncol, 44 Binney St, Boston, MA 02115 USA. NR 41 TC 71 Z9 72 U1 1 U2 7 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0732-183X J9 J CLIN ONCOL JI J. Clin. Oncol. PD MAY PY 1999 VL 17 IS 5 BP 1625 EP 1631 PG 7 WC Oncology SC Oncology GA 195TH UT WOS:000080267900039 PM 10334552 ER PT J AU Horton, MC Lewis, TE Kinsey, TV AF Horton, MC Lewis, TE Kinsey, TV TI Reengineering the picture archiving and communication system (PACS) process for digital imaging networks PACS SO JOURNAL OF DIGITAL IMAGING LA English DT Article; Proceedings Paper CT 16th Symposium for Computer Applications in Radiology on PACS - Performance Improvement in Radiology (SCAR 99), at the Annual Meeting of SCAR CY MAY 06-09, 1999 CL HOUSTON, TEXAS SP Soc Comp Applicat Radiol AB Prior to June 1997, military picture archiving and communications systems (PACS) were planned, procured, and installed with key decisions on the system, equipment, and even funding sources made through a research and development office called Medical Diagnostic Imaging Systems (MDIS). Beginning in June 1997, the Joint Imaging Technology Project Office (JITPO) initiated a collaborative and consultative process far planning and implementing PACS into military treatment facilities through a new Department of Defense (DoD) contract vehicle called digital imaging networks (DIN)-PACS. The JITPO reengineered this process incorporating multiple organizations and politics. The reengineered PACS process administered through the JITPO transformed the decision process and accountability from a single office to a consultative method that increased end-user knowledge, responsibility, and ownership in PACS. The JITPO continues to provide information and services that assist multiple groups and users in rendering PACS planning and implementation decisions. Local site project managers are involved from the outset and this end-user collaboration has made the sometimes difficult transition to PACS an easier and more acceptable process for all involved. Corporately, this process saved DoD sites millions by having PACS plans developed within the government and proposed to vendors second, and then having vendors respond specifically to those plans. The integrity and efficiency of the process have reduced the opportunity for implementing nonstandard systems while sharing resources and reducing wasted government dollars. This presentation will describe the chronology of changes, encountered obstacles, and lessons learned within the reengineering of the PACS process for DIN-PACS. This is a US government work. There are no restrictions on its use. C1 USN, Joint Imaging Technol Project Off, Ft Detrick, MD 21702 USA. RP Horton, MC (reprint author), USN, Joint Imaging Technol Project Off, 1056 Patchel Rd, Ft Detrick, MD 21702 USA. NR 6 TC 1 Z9 1 U1 1 U2 2 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0897-1889 J9 J DIGIT IMAGING JI J. Digit. Imaging PD MAY PY 1999 VL 12 IS 2 SU 1 BP 59 EP 61 PG 3 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 197GB UT WOS:000080356100016 PM 10342167 ER PT J AU Vurgaftman, I Meyer, JR Hoffman, CA Cho, S Ketterson, JB Faraone, L Antoszewski, J Lindemuth, JR AF Vurgaftman, I Meyer, JR Hoffman, CA Cho, S Ketterson, JB Faraone, L Antoszewski, J Lindemuth, JR TI Quantitative mobility spectrum analysis (QMSA) for Hall characterization of electrons and holes in anisotropic bands SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 40th Electronic Materials Conference (EMC-40) CY JUN 24-26, 1998 CL UNIV VIRGINIA, CHARLOTTESVILLE, VIRGINIA SP TMS HO UNIV VIRGINIA DE anisotropic bands; Bi CdTe superlattices; Bi films; magnetotransport; quantitative mobility spectrum analysis (QMSA); Si; thermoelectric properties ID MAGNETOTRANSPORT CHARACTERIZATION; TRANSPORT-PROPERTIES; BISMUTH; FILMS AB An extension of the quantitative mobility spectrum analysis (QMSA) procedure, which determines free electron and hole densities and mobilities from magnetic-field-dependent Hall and resistivity measurements, to materials exhibiting anisotropic conduction is presented. As test cases, the fully computer-automated procedure is used to analyze magnetotransport data from Bi thin films and Bi/CdTe superlattices. Using the results of the QMSA procedure, the thermoelectric properties of these films can be accurately modeled. As a second example, an electron mobility anisotropy ratio of approximate to 4.5 is derived from the QMSA treatment of the Hall data for bulk Si samples. C1 USN, Res Lab, Washington, DC 20375 USA. Northwestern Univ, Dept Phys, Evanston, IL 60208 USA. Univ Western Australia, Dept Elect & Elect Engn, Nedlands, WA 6907, Australia. Lake Shore Cryotron Inc, Westerville, OH 43082 USA. RP Vurgaftman, I (reprint author), USN, Res Lab, Code 5613, Washington, DC 20375 USA. RI Ketterson, John/B-7234-2009 NR 16 TC 10 Z9 11 U1 0 U2 2 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD MAY PY 1999 VL 28 IS 5 BP 548 EP 552 DI 10.1007/s11664-999-0110-2 PG 5 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 195UC UT WOS:000080269700025 ER PT J AU Warren, HP Hassler, DM AF Warren, HP Hassler, DM TI The density structure of a solar polar coronal hole SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID WAVE COLLISION STRENGTHS; LINE RATIOS; OSCILLATOR-STRENGTHS; ION TEMPERATURES; SUMER TELESCOPE; EMISSION-LINES; SI-III; WIND; SOHO; 8-LESS-THAN-OR-EQUAL-TO-Z-LESS-THAN-OR-EQUAL-TO-92 AB Electron densities derived from Si III, Ne VII, Mg VIII, Si VIII, and Mg IX line ratios observed above the limb of a polar coronal hole with the Solar Ultraviolet Measurements of Emitted Radiation (SUMER) spectrometer on the Solar and Heliospheric Observatory (SoHO) are presented. The electron densities are consistent with a constant pressure of 1.6 x 10(14) cm(-3) K (log P-e = 14.2). C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. SW Res Inst, Boulder, CO 80302 USA. RP Warren, HP (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS 58, Cambridge, MA 02138 USA. NR 38 TC 10 Z9 10 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAY 1 PY 1999 VL 104 IS A5 BP 9781 EP 9789 DI 10.1029/1998JA900079 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 192BQ UT WOS:000080058600011 ER PT J AU Hicks, GT Chubb, TA Meier, RR AF Hicks, GT Chubb, TA Meier, RR TI Observations of hydrogen Lyman alpha emission from missile trails SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID FAR ULTRAVIOLET; ATMOSPHERE; GEOCORONA AB The Naval Research Laboratory far ultraviolet experiment on board the OGO 4 satellite accidentally detected hydrogen Lyman alpha emission following the passage of missiles through the upper atmosphere. The deposition of hydrogenous exhaust products above 100 km results in a local enhancement of hydrogen, which resonantly scatters Lyman alpha radiation from the Sun and from the geocorona, and produces a far ultraviolet contrail. The observed local enhancement of radiation was as much as 37% above the natural background. All event detections took place at time intervals of 6 min to 10 hours following the passage of a missile or spacecraft. There was no opportunity to observe prompt emissions. We describe the observations of this unusual phenomenon and the implications for hydrogen production mechanisms. C1 USN, EO Hulburt Ctr Space Res, Res Lab, Washington, DC 20375 USA. RP Hicks, GT (reprint author), 810 Bryan Point Rd, Accokeek, MD 20607 USA. RI Meier, Robert/G-4749-2014 OI Meier, Robert/0000-0001-8497-7115 NR 22 TC 4 Z9 4 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAY 1 PY 1999 VL 104 IS A5 BP 10101 EP 10109 DI 10.1029/1999JA900029 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 192BQ UT WOS:000080058600038 ER PT J AU Reynolds, MA Ganguli, G Fedder, JA Lemaire, J Meier, RR Melendez-Alvira, DJ AF Reynolds, MA Ganguli, G Fedder, JA Lemaire, J Meier, RR Melendez-Alvira, DJ TI Thermal plasmaspheric morphology: Effect of geomagnetic and solar activity SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ION MASS-SPECTROMETER; OUTER PLASMASPHERE; INNER MAGNETOSPHERE; CONVECTION; MODEL; PLASMAPAUSE; DE-1; HE+ AB A multispecies kinetic model of the thermal plasma in the plasmasphere is used to predict the spatial dependence of the hydrogen ion and helium ion density and temperature for different levels of geomagnetic and solar activity. The particular convection electric field model chosen is intended for the time intervals between substorms. The plasma density and temperature in the equatorial plane are found to exhibit a local-time variation that is sensitive to the details of the convection electric field. In particular, the parallel temperature increases with altitude and the perpendicular temperature decreases with altitude, except in the postmidnight sector, features that are only possible if kinetic effects are taken into account. In addition, the ratio of the helium ion density to the hydrogen ion density is found to agree with observations of the Dynamics Explorer 1 satellite. This behavior can be explained by the effects of convection on the thermal particles that are magnetically trapped on closed field lines. These results have implications for the interpretation and analysis of sunlight scattered by helium ions (He II) to be measured by future global imaging satellites. C1 USN, Res Lab, Div Plasma Phys, Beam Phys Branch, Washington, DC 20375 USA. Sachs Freeman Associates Inc, Landover, MD 20785 USA. Inst Aeron Spatiale Belgique, B-1180 Brussels, Belgium. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Reynolds, MA (reprint author), Howard Univ, Dept Phys & Astron, 2355 6th St NW, Washington, DC 20059 USA. RI Meier, Robert/G-4749-2014 OI Meier, Robert/0000-0001-8497-7115 NR 32 TC 7 Z9 7 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAY 1 PY 1999 VL 104 IS A5 BP 10285 EP 10294 DI 10.1029/1999JA900050 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 192BQ UT WOS:000080058600053 ER PT J AU Park, SY Ross, IM AF Park, SY Ross, IM TI Two-body optimization for deflecting earth-crossing asteroids SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article ID COLLISION COURSE; SHOEMAKER-LEVY-9; INTERCEPTION; JUPITER; COMET AB We present a formulation of a finite-dimensional optimization problem associated with the deflection of Earth-crossing asteroids. The performance measure is minimizing the delta-V requirement for achieving a minimum target separation distance. A number of astrodynamical constraints are identified and modeled. The constrained optimization problem is numerically, solved using a sequential quadratic programming method. Our numerical analysis indicates that the minimum delta-V requirement is not a monotonically decreasing function of warning time; rather, there is a finer structure associated with the orbital period of the colliding asteroid. The analysis tool presented here may be used for optimizing the interceptor mission for impact mitigation. C1 USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. RP Park, SY (reprint author), USN, Postgrad Sch, Dept Aeronaut & Astronaut, Mail Code AA RO,699 Dyer Rd, Monterey, CA 93943 USA. RI Park, Sang-Young/F-5989-2013 NR 17 TC 19 Z9 19 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD MAY-JUN PY 1999 VL 22 IS 3 BP 415 EP 420 DI 10.2514/2.4413 PG 6 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 196KK UT WOS:000080307400005 ER PT J AU Song, GB Buck, NV Agrawal, BN AF Song, GB Buck, NV Agrawal, BN TI Spacecraft vibration reduction using pulse-width pulse-frequency modulated input shaper SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article; Proceedings Paper CT AIAA Guidance, Navigation, and Control Conference CY AUG 07, 1997-AUG 10, 1998 CL BALTIMORE, MARYLAND SP Amer Inst Aeronaut & Astronaut ID FLEXIBLE SPACECRAFT; ATTITUDE-CONTROL AB Minimizing vibrations of a flexible spacecraft actuated by on-off thrusters is a challenging task. This paper presents the first study of pulse-width pulse-frequency modulated thruster control using command input shaping. Input shaping is a technique that uses a shaped command to ensure zero residual vibration of a flexible structure. Pulse-width pulse-frequency modulation is a control method that provides pseudolinear operation for an on-off thruster. The proposed method takes full advantage of the pseudolinear property of a pulse-width pulse frequency modulator and integrates it with a command shaper to minimize the vibration of a flexible spacecraft induced by on off thruster firing. Compared to other methods, this new approach has numerous advantages: 1) effectiveness in vibration suppression, 2) dependence only on modal frequency and damping, 3) robustness to variations in modal frequency and damping, and 4) easy computation. Numerical simulations performed on an eight-mode model of the Flexible Spacecraft Simulator in the Spacecraft Research and Design Center at the U.S. Naval Postgraduate School demonstrate the efficacy and robustness of the method. C1 Univ Akron, Dept Mech Engn, Akron, OH 44325 USA. USN, Postgrad Sch, Dept Aeronaut & Astronaut, Monterey, CA 93943 USA. USN, Postgrad Sch, Spacecraft Res & Design Ctr, Monterey, CA 93943 USA. RP Song, GB (reprint author), Univ Akron, Dept Mech Engn, Akron, OH 44325 USA. NR 12 TC 46 Z9 52 U1 0 U2 12 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD MAY-JUN PY 1999 VL 22 IS 3 BP 433 EP 440 DI 10.2514/2.4415 PG 8 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 196KK UT WOS:000080307400007 ER PT J AU Feldman, JL Eggert, JH De Kinder, J Mao, HK Hemley, RJ AF Feldman, JL Eggert, JH De Kinder, J Mao, HK Hemley, RJ TI Influence of order-disorder on the vibron excitations of H-2 and D-2 in ortho-para mixed crystals SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article ID X-RAY-DIFFRACTION; SOLID HYDROGEN; QUANTUM PERCOLATION; LOCALIZED STATES; HIGH-PRESSURES; DEUTERIUM; DEPENDENCE; SCATTERING; EQUATION; ALLOY AB We present a detailed experimental and theoretical study of the vibrons in ortho-para mixed crystals of solid hydrogen and deuterium at ambient and high pressure. Experimental results were obtained at ambient pressure and T = 6-7 K (e.g., for hydrogen samples having ortho fractions of 19-62%) using high-resolution Fabry-Perot techniques, and at high pressure and T = 77 K (e.g., hydrogen 50-50% ortho-para samples) using dispersive spectrographic techniques with diamond-anvil cells. The numerical calculations are based on the James and Van Kranendonk theory, and were performed by exactly diagonalizing the Hamiltonian for a large supercell of randomly placed molecular "species" on a crystalline lattice. Overall, excellent agreement between theory and experiment is obtained. The calculations show that disorder leads to Anderson localized vibrons for many of the pressures and concentrations studied experimentally and that a substantial portion of the Raman intensity is derived from these localized vibrons. We also calculate the species characteristics of the individual Raman peaks, the results of which suggest an explanation for the previously noted disagreement between experimental high-pressure results and the predictions of the van Kranendonk theory. Specifically, our analysis indicates that the higher frequency peak is associated with anisotropic scattering arising from partial alignment of J = 1 angular momenta with respect to the crystallographic axes. Finally, our calculations show that the observed doublet structure in the lower frequency Raman peak for deuterium at low para (J = 1) concentrations is well represented by added (para-molecule) diagonal terms in the van Kranendonk Hamiltonian that are plausibly associated with electric quadrupole-quadrupole interactions. C1 USN, Ctr Computat Mat Sci, Res Lab, Washington, DC 20375 USA. Colorado Sch Mines, Dept Phys, Golden, CO 80401 USA. INCC, NICC, B-1120 Brussels, Belgium. Carnegie Inst Washington, Geophys Lab, Washington, DC 20015 USA. Carnegie Inst Washington, Ctr High Pressure Res, Washington, DC 20015 USA. RP Feldman, JL (reprint author), USN, Ctr Computat Mat Sci, Res Lab, Washington, DC 20375 USA. NR 40 TC 5 Z9 5 U1 0 U2 0 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD MAY PY 1999 VL 115 IS 3-4 BP 181 EP 216 DI 10.1007/BF02876021 PG 36 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 199VY UT WOS:000080505800006 ER PT J AU Skumryev, V Blythe, HJ Cullen, J Coey, JMD AF Skumryev, V Blythe, HJ Cullen, J Coey, JMD TI AC susceptibility of a magnetite crystal SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article; Proceedings Paper CT 7th European Magnetic Materials and Applications Conference (EMMA 98) CY SEP 09-12, 1998 CL ZARAGOZA, SPAIN SP Comis Interministerial Ciencia & Tecnoloiga, Consejo Super Investigaciones Cientificas, Diputac Gen Aragon, OPEL-Espana, Univ Zaragoza DE AC susceptibility; magnetite; spin reorientation transitions; relaxations ID VERWEY TRANSITION-TEMPERATURE; FE3O4 AB The AC susceptibility of an Fe3O4 crystal has been studied from 4.2 to 300 K with field applied along a [1 1 0] direction. There is a sharp peak in chi' and minimum in chi " at 130 K where K-1 changes sign, a precipitous drop in chi' and maximum in chi " at the Verwey transition and a further, frequency-dependent decrease in chi' accompanied by peak in chi " below 50 K. The low-temperature behavior is associated with an activated relaxation process having tau(0) = 6 x 10(-9) s, E-a = 0.04 eV which is due to the coupled electron hopping and domain wall motion. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Univ Dublin Trinity Coll, Dept Phys, Dublin 2, Ireland. Univ Sheffield, Dept Phys & Astron, Sheffield, S Yorkshire, England. USN, Ctr Surface Warfare, W Bethesda, MD 20817 USA. RP Coey, JMD (reprint author), Univ Dublin Trinity Coll, Dept Phys, Dublin 2, Ireland. EM jcoey@tcd.ie RI Skumryev, Vassil/B-1440-2012 OI Skumryev, Vassil/0000-0003-1375-4824 NR 10 TC 40 Z9 40 U1 2 U2 15 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD MAY PY 1999 VL 196 BP 515 EP 517 DI 10.1016/S0304-8853(98)00863-4 PG 3 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 195VB UT WOS:000080271900194 ER PT J AU Rubinstein, M Lubitz, P Cheng, SF AF Rubinstein, M Lubitz, P Cheng, SF TI Ferromagnetic-resonance field shift in an exchange-biased CoO/Ni80Fe20 bilayer SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article DE ferromagnetic resonance; exchange bias; field shift; bilayers ID UNIDIRECTIONAL ANISOTROPY; FILMS AB The temperature dependence of the ferromagnetic resonance field shift has been investigated in a CoO/Permalloy bilayer between room temperature and 4 K. The field shift is found to consist of two components: a unidirectional exchange-bias field shift and a uniaxial anisotropic field shift. These field shifts are shown to be equal to the conventional exchange bias and anisotropy fields, provided the rigid spin rotation hypothesis is correct. We have also measured the temperature variation of the exchange bias and the magnetic anisotropy fields from hysteresis loops obtained from SQUID-magnetometry, and found incomplete agreement with the parameters obtained from the ferromagnetic resonance spectra. Analogies with spin-glass phenomena indicate that this incomplete agreement results from the breakdown of the rigid rotation model (or equivalently, the surface anisotropy model) results due to the large rotation angles encountered in a magnetic moment reversal. Notwithstanding, we show that the results of rotating the sample by 180 degrees in the plane of the film yields changes in the resonance field shift which are in agreement with hysteresis loop parameters. A connection between results observed in exchange bias materials and those in spin-glass materials is suggested. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. RP Rubinstein, M (reprint author), USN, Res Lab, Code 6340, Washington, DC 20375 USA. NR 26 TC 34 Z9 35 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD MAY PY 1999 VL 195 IS 2 BP 299 EP 306 DI 10.1016/S0304-8853(99)00129-8 PG 8 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 196HH UT WOS:000080302600009 ER PT J AU Xu, L Troesch, AW Peterson, R AF Xu, L Troesch, AW Peterson, R TI Asymmetric hydrodynamic impact and dynamic response of vessels SO JOURNAL OF OFFSHORE MECHANICS AND ARCTIC ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID STEADY AB Theoretical simulations are compared with drop test experiments of vessel free fall impact on calm water with zero and nonzero initial heel angles. The impact force and moment are predicted by using a theory described in Xu et al. (1998). The resulting motions of vessels at asymmetric impact include vertical water entry and transverse rolling. The downward deceleration equation combines the hydrostat ic and hydrodynamic forces and the weight of hull, while the rolling equation takes into account the restoring moments due to asymmetry. Another simplified approach of a water entry dynamics and injury model (Gollwitzer and Peterson, 1996) is also applied to evaluate the impact acceleration for symmetric cases. The experiments were conducted at the Coastal systems station, panama City, Florida, using a 2 Sr x 8 ft (0.61 m x 2.44 m) prismatic hull model with 20 deg deadrise. The comparisons between the asymmetric impact theory and experiment shows varying degrees of qualitative and quantitative agreement. C1 Amer Bur Shipping, Two World Trade Ctr, Dept Res & Dev, New York, NY 10048 USA. Univ Michigan, Dept Naval Architecture & Marine Engn, Ann Arbor, MI 48109 USA. USN, Surface Warfare Ctr, Dahlgren Div, Coastal Syst Stn, Panama City, FL 32407 USA. RP Xu, L (reprint author), Amer Bur Shipping, Two World Trade Ctr, Dept Res & Dev, New York, NY 10048 USA. NR 19 TC 12 Z9 15 U1 1 U2 5 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0892-7219 J9 J OFFSHORE MECH ARCT JI J. Offshore Mech. Arct. Eng. Trans. ASME PD MAY PY 1999 VL 121 IS 2 BP 83 EP 89 DI 10.1115/1.2830082 PG 7 WC Engineering, Ocean; Engineering, Mechanical SC Engineering GA 198PX UT WOS:000080434100004 ER PT J AU Frenkel, AI Cross, JO Fanning, DM Robinson, IK AF Frenkel, AI Cross, JO Fanning, DM Robinson, IK TI DAFS analysis of magnetite SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE diffraction anomalous fine-structure; magnetite; Verwey transition ID SCATTERING AB The mechanism of the structural transformation in Fe3O4 during its Verwey transition at 120 K is not completely understood, partly due to the lack of knowledge of the details of the local structure around different Fe atoms in the unit cell. In our experiment, this information was obtained at room temperature using Diffraction Anomalous Fine Structure (DAFS) technique which has the ability to separately solve the local, structures around the octahedral and tetrahedral sites in the spinel structure of magnetite. An iterative dispersion integral algorithm was used to isolate f' and f " from the DAFS intensity and structural information was obtained from f " using standard XAFS analysis methods. Relevance of our results to different models of Verwey transition is discussed. C1 Univ Illinois, Urbana, IL 61801 USA. USN, Res Lab, Washington, DC 20375 USA. RP Frenkel, AI (reprint author), Univ Illinois, Urbana, IL 61801 USA. RI Frenkel, Anatoly/D-3311-2011 OI Frenkel, Anatoly/0000-0002-5451-1207 NR 9 TC 11 Z9 11 U1 0 U2 5 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 332 EP 334 DI 10.1107/S0909049598013636 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700076 PM 15263298 ER PT J AU Cross, JO Elam, WT Woicik, JC Sorensen, LB AF Cross, JO Elam, WT Woicik, JC Sorensen, LB TI Reliability of structural parameters determined from DAFS data using the iterative dispersion integral algorithm SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE DAFS; Kramers-Kronig; analysis ID ANOMALOUS FINE-STRUCTURE; DIFFRACTION AB The iterative Kramers-Kronig (IKK) dispersion integral algorithm is commonly used to isolate the complex resonant scattering amplitude Delta f = f' + if " from measured diffraction anomalous fine structure (DAFS) intensity data, where the imaginary part f " is then analyzed in the same manner as the absorption coefficient mu. We have performed studies using simulated and experimental DAFS data to evaluate the reliability of structural parameters determined from f " resolved by the IKK algorithm. The results of a few of these experiments are presented here. C1 USN, Res Lab, Washington, DC 20375 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Washington, Seattle, WA 98195 USA. RP Cross, JO (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 7 TC 5 Z9 5 U1 0 U2 3 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 335 EP 337 DI 10.1107/S0909049598018226 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700077 PM 15263299 ER PT J AU Mansour, AN Mukerjee, S Yang, XQ McBreen, J AF Mansour, AN Mukerjee, S Yang, XQ McBreen, J TI In situ XAS of the reaction mechanism of lithium with tin-based composite oxide glass SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, IL HO ILLINOIS INST TECHNOL DE in situ XAFS; tin-based composite oxide; structure AB We have measured the XAFS spectra of tin-based composite oxide (TCO) glass with nominal composition of Sn1.0B0.56P0.40Al0.42O3.47 during the discharge and charge cycles in an in a non-aqueous cell. Our results confirm the amorphous nature of TCO material and show that Sn in TCO is coordinated with 3 oxygen atoms at a distance of 2.12 Angstrom. Upon discharge (i.e., Li insertion), initially, Li interacts with the electrochemically active Sn-O center forming metallic Sn, most likely in the form of highly dispersed clusters, and Li2O. Upon further discharge, our results are consistent with a model in which additional Li alloys with Sn forming various alloys with composition dependent on the amount of Li inserted. The formed alloys appear to be in the form of highly dispersed clusters and/or amorphous in nature. Their local structure differs somewhat from the crystalline structure of the known Li-Sn alloys such as LiSn, Li7Sn3, or Li7Sn2. Upon charging (i.e., Li removal), metallic Sn is reversibly produced with a Sn-Sn distance intermediate to those of gray and white Sn. C1 USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RP USN, Ctr Surface Warfare, Carderock Div, Code 684, Bethesda, MD 20817 USA. NR 10 TC 17 Z9 17 U1 3 U2 18 PU INT UNION CRYSTALLOGRAPHY PI CHESTER PA 2 ABBEY SQ, CHESTER, CH1 2HU, ENGLAND SN 1600-5775 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 596 EP 598 DI 10.1107/S0909049598017026 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700170 PM 15263392 ER PT J AU O'Grady, WE Ramaker, DE AF O'Grady, WE Ramaker, DE TI Shape resonances and EXAFS scattering in the Pt L-2,3 XANES from a Pt electrode SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE EXAFS; XANES; electrochemistry; platinum electrode; shape resonances AB Atomic hydrogen and oxygen adsorption on a platinum electrode in H2SO4 and HClO4 electrolytes were studied by Pt L-23 XANES. The Pt electrode was formed of highly dispersed 1.5-3.0 nm particles supported on carbon. A difference procedure utilizing the L-2 acid L-3 spectra at various applied voltages was used to isolate the electronic and geometric effects in the XANES spectra. At 0.54 V (relative to RHE) the Pt electrode in HClO4 is assumed to be "clean". By taking the difference between the spectra at 0.0 and 0.54 V, the Pt-H antibonding state (electronic effect) is isolated and found to have a Fano-resonance line shape. In addition, a significant R-K EXAFS scattering (geometric effect) was found for photon energies 0 to 20 eV above the edge. The difference between the spectra at 1.14 and 0.54 V allows isolation of the Pt-O antibonding state and the Pt-O EXAFS scattering. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. George Washington Univ, Dept Chem, Washington, DC 20052 USA. RP O'Grady, WE (reprint author), USN, Res Lab, Div Chem, Washington, DC 20375 USA. NR 7 TC 2 Z9 2 U1 1 U2 4 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 599 EP 601 DI 10.1107/S0909049599000035 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700171 PM 15263393 ER PT J AU Wende, H Srivastava, P Arvanitis, D Wilhelm, F Lemke, L Ankudinov, A Rehr, JJ Freeland, JW Idzerda, YU Baberschke, K AF Wende, H Srivastava, P Arvanitis, D Wilhelm, F Lemke, L Ankudinov, A Rehr, JJ Freeland, JW Idzerda, YU Baberschke, K TI Magnetic L-edge EXAFS of 3d elements: multiple-scattering analysis and spin dynamics SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE temperature dependent magnetic EXAFS ID ABSORPTION FINE-STRUCTURE; CIRCULAR-DICHROISM AB Magnetic EXAFS (MEXAFS) adds magnetic selectivity to the well established EXAFS technique opening the door to the exploration of local magnetic structure and disorder. Of particular interest is the behavior of 3d transition metal systems. By utilizing the enhanced L-3,L-2 MEXAFS signal, which is one order of magnitude larger than the K-edge MEXAFS, we performed a temperature dependent study of polycrystalline and epitaxially grown Fe and Co films. By analyzing single and multiple scattering contributions to the helicity dependent data, it is found that there are enhanced multiple scattering contributions in the magnetic case. In addition, we discuss the temperature dependence of the MEXAFS data which is linked to spin fluctuations. C1 Free Univ Berlin, Inst Expt Phys, D-14195 Berlin, Germany. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden. Univ Washington, Dept Phys, Seattle, WA 98175 USA. USN, Res Lab, Washington, DC 20375 USA. RP Baberschke, K (reprint author), Free Univ Berlin, Inst Expt Phys, Arnimallee 14, D-14195 Berlin, Germany. RI Wende, Heiko/J-8505-2012 NR 13 TC 14 Z9 14 U1 0 U2 5 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 696 EP 698 DI 10.1107/S0909049598017488 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700205 PM 15263427 ER PT J AU Islam, S Liou, MB Fatemi, DJ Cross, JO Harris, VG Elam, WT AF Islam, S Liou, MB Fatemi, DJ Cross, JO Harris, VG Elam, WT TI Evolution of long-range and short-range order in La0.67Ca0.33MnO3-delta during solid-state transformation using high-energy ball milling SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE ball-milling; extended x-ray absorption fine structure; colossal magnetoresistance; manganates ID MAGNETORESISTANCE; FILMS AB A novel processing scheme has been developed that allows for the single step processing of nanostructured complex oxides. This approach involves the high energy ball-milling (HEBM) of binary oxide precursors to form pure phase complex oxides at low-temperatures. Using this technique we have prepared La0.67Ca0.33MnO3-delta and studied the evolution of short range and long-range order, using EXAFS and XRD respectively, as a function of milling lime during the solid state transformation. Transport properties of the milled perovskites are also discussed. C1 Virginia Union Univ, Richmond, VA USA. Cornell Univ, Ithaca, NY 14853 USA. USN, Res Lab, Washington, DC 20375 USA. RP Islam, S (reprint author), Virginia Union Univ, Richmond, VA USA. RI Harris, Vincent/A-8337-2009 NR 7 TC 2 Z9 2 U1 0 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 773 EP 775 DI 10.1107/S0909049598016240 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700232 PM 15263454 ER PT J AU Ramaker, DE O'Grady, WE AF Ramaker, DE O'Grady, WE TI 'Atomic' XAFS as a probe of electronic structure SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE EXAFS; atomic XAFS; electrochemistry; zincate; ion-pair interactions ID ABSORPTION FINE-STRUCTURE; EMBEDDED ATOMS AB Atomic XAFS (AXAFS) offers the potential for a new tool to gain relatively detailed electronic structure and polarization information on systems, in-situ, that may not contain long range geometric order. We have shown previously that AXAFS can monitor changes in the charge of less than 0.05e per surface Pt atom on a metallic cluster, and "sees" interactions from ions 2 and 3 shells removed from the absorber atom. The AXAFS lineshape allows a differentiation between the through space field polarization and the through bond inductive effects. Applications have been made to In situ Pt electrodes, ion-cation interactions in solution, and supported noble metal catalysts. C1 George Washington Univ, Dept Chem, Washington, DC 20052 USA. George Washington Univ, Inst Mat Sci, Washington, DC 20052 USA. USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Ramaker, DE (reprint author), George Washington Univ, Dept Chem, Washington, DC 20052 USA. NR 15 TC 6 Z9 6 U1 0 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 800 EP 802 DI 10.1107/S0909049599003921 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700242 PM 15263464 ER PT J AU Steger, JW Matthews, JH AF Steger, JW Matthews, JH TI UVA therapy for scleroderma SO JOURNAL OF THE AMERICAN ACADEMY OF DERMATOLOGY LA English DT Letter ID LOCALIZED SCLERODERMA C1 USN, Med Ctr, Dept Dermatol, San Diego, CA 92134 USA. RP Steger, JW (reprint author), USN, Med Ctr, Dept Dermatol, San Diego, CA 92134 USA. NR 3 TC 13 Z9 14 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0190-9622 J9 J AM ACAD DERMATOL JI J. Am. Acad. Dermatol. PD MAY PY 1999 VL 40 IS 5 BP 787 EP 787 PN 1 PG 1 WC Dermatology SC Dermatology GA 191PA UT WOS:000080029700028 PM 10321617 ER PT J AU Natishan, PM O'Grady, WE McCafferty, E Ramaker, DE Pandya, K Russell, A AF Natishan, PM O'Grady, WE McCafferty, E Ramaker, DE Pandya, K Russell, A TI Chloride uptake by oxide covered aluminum as determined by X-ray photoelectron and X-ray absorption spectroscopy SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID PASSIVITY; ALLOYS; MECHANISM; CORROSION; METALS AB The uptake of chloride by aluminum polarized at potentials below (less positive than) the pitting potential in 0.1 M NaCl solutions was studied using X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS). The XPS chloride spectra showed that-two distinct sets of doublets are present. One doublet is related to chloride on the surface and the second is related to chloride incorporated in the oxide film. In the case of XAS, deconvolution of the spectrum obtained for samples polarized below the pitting potential also showed the presence of chloride in the near surface region and in the oxide film. The important point of this work is that the observed chloride was present in two different chemical environments as determined with both XAS and XPS. (C) 1999 The Electrochemical Society. S0013-4651(98)07-030-X. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. N Carolina State Univ, Raleigh, NC 27695 USA. George Washington Univ, Washington, DC 20052 USA. Univ Southampton, Dept Chem, Southampton SO9 5NH, Hants, England. RP Natishan, PM (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Russell, Andrea/B-8114-2009; Russell, Andrea/A-9625-2012 NR 30 TC 26 Z9 26 U1 1 U2 8 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD MAY PY 1999 VL 146 IS 5 BP 1737 EP 1740 DI 10.1149/1.1391835 PG 4 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 197AW UT WOS:000080343300021 ER PT J AU Mokole, EL Samaddar, SN AF Mokole, EL Samaddar, SN TI Transmission and reflection of normally incident, pulsed electromagnetic plane waves upon a Lorentz half-space SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID UNIFORM ASYMPTOTIC DESCRIPTION; LINEAR DISPERSIVE MEDIUM; PROPAGATION; ABSORPTION AB One-dimensional propagation of a normally incident, pulsed electromagnetic plane wave upon an isotropic, spatially homogeneous, Lorentz half-space is investigated analytically. Fourier integral representations of the time-dependent reflected and transmitted fields are obtained for an arbitrary incident pulse, and detailed examinations of these fields are made when the incident field is a finite-cycle-sine function. The inversion integral for the time-dependent reflected field is expressed in terms of the pole contribution and branch-cut integrals, whereas the uniform asymptotic methodology of Oughstun and Sherman [J. Opt. Sec. Am. A 6, 1394 (1989)] is applied to the transmitted field. Only the contribution from the distant saddle points to the transmitted field is studied in detail. An example is provided that shows that the effects of including the reflection and transmission coefficients may not be ignored when microwave or optical pulses are launched across the interface. Specifically, for Brillouin's choice of the medium's physical parameters, the reflected field has a peak Value that is 21% of the incident field's amplitude and that corresponds to a 21% decrease in the main signal (pole contribution)of the transmitted field when the transmission coefficient is unity. This study extends past analytical formulations of the one-dimensional problem by conducting an in-depth analysis of the reflected field for a normally incident finite-cycle-sine wave and by addressing how inclusion of frequency-dependent transmission and reflection coefficients affects the fields. In particular, situations for which the effect of the frequency-dependent transmission and reflection coefficients is significant are discussed. Finally, the analysis of the reflected field should be useful for diagnostic purposes. C1 USN, Res Lab, Washington, DC 20375 USA. RP Mokole, EL (reprint author), USN, Res Lab, Code 5340,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 31 TC 5 Z9 5 U1 0 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD MAY PY 1999 VL 16 IS 5 BP 812 EP 831 DI 10.1364/JOSAB.16.000812 PG 20 WC Optics SC Optics GA 195AL UT WOS:000080226900017 ER PT J AU Calkins, MD Robinson, TD AF Calkins, MD Robinson, TD TI Combat trauma airway management: Endotracheal intubation versus laryngeal mask airway versus combitube use by navy SEAL and Reconnaissance combat corpsmen SO JOURNAL OF TRAUMA-INJURY INFECTION AND CRITICAL CARE LA English DT Article; Proceedings Paper CT 58th Annual Meeting of the American-Association-for-the-Surgery-of-Trauma/Trauma-Association-of-Can ada CY SEP 24-26, 1998 CL BALTIMORE, MARYLAND SP Amer Assoc Surg Trauma, Trauma Assoc Canada DE combat; trauma; airway; endotracheal tube; laryngeal mask airway; esophageal tracheal combitube ID TRACHEAL TUBE; RESUSCITATION; FACEMASK; CARE; CRICOTHYROTOMY; ANESTHESIOLOGY; METAANALYSIS; VENTILATION; PARAMEDICS; PERSONNEL AB Background: Airway management takes precedence regardless of what type of life support is taking place. The gold standard for airway control and ventilation in the hands of the experienced paramedic remains unarguably the endotracheal tube. Unfortunately, laryngoscopy and endotracheal intubation require a skilled provider who performs this procedure on a frequent basis. Special Operations corpsmen and medics receive training in the use of the endotracheal tube, but they use it infrequently. The use of alternative airways by Navy SEAL and Reconnaissance combat corpsmen has not been evaluated, Our objective was to compare the ability of Special Operations corpsmen to use the endotracheal tube (ETT), laryngeal mask airway (LMA), and esophageal-tracheal combitube (ETC) under combat conditions. Methods: This study used a prospective, randomized, crossover design. Twelve Navy SEAL or Reconnaissance combat corpsmen participated in a 2-week Advanced Battlefield Trauma course. During the first week, instruction included the use of ETT, LMA, and ETC, viewing of videotapes far ETC and LMA, and mannequin training. The Special Operations corpsmen were required to reliably insert each airway within 40 seconds. During the second week, participants dealt with a number of active combat trauma scenarios under fire in combat conditions. Each SEAL or Reconnaissance corpsman was asked to control his "casualty's" airway with a randomized device. All participants were evaluated in the use of each of the three airways. Results: Thirty-six airway insertions were evaluated, No failures occurred. All incorrect placements were detected and corrected. Mean time to place the ETT was 36.5 seconds versus 40.0 seconds for the ETC. The LMA insertion time of 22.3 seconds was significantly shorter than the other times (p < 0.05), The mean number of attempts per device was similar with all devices: LMA (1.17), ETC (1.17), and ETT (1.25), Conclusion: The Special Operations corpsmen easily learned how to use the ETC and LMA, In this study, they showed the ability to appropriately use the ETT as well as the ETC and LMA, For SEAL corpsmen, the alternative airways should not replate the ETT; however, on occasion an advanced combat casualty care provider may not be able to use the laryngoscope or may be unable to place the ETT, The LMA and ETC are useful alternatives in this situation. If none of these airways are feasible, cricothyrotomy remains an option. Regardless of the airway device, refresher training must take place frequently. C1 Walter Reed Army Inst Res, Div Surg, Washington, DC 20307 USA. Walter Reed Army Med Ctr, Washington, DC 20307 USA. USN, Special Warfare Grp Med 1, San Diego, CA 92152 USA. RP Calkins, MD (reprint author), Walter Reed Army Inst Res, Div Surg, 14th & Dahlia,Bldg 40, Washington, DC 20307 USA. NR 31 TC 23 Z9 23 U1 1 U2 4 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1079-6061 J9 J TRAUMA JI J. Trauma-Injury Infect. Crit. Care PD MAY PY 1999 VL 46 IS 5 BP 927 EP 932 DI 10.1097/00005373-199905000-00025 PG 6 WC Critical Care Medicine; Surgery SC General & Internal Medicine; Surgery GA 196EA UT WOS:000080295000035 PM 10338414 ER PT J AU Eddy, CR Leonhardt, D Douglass, SR Shamamian, VA Thoms, BD Butler, JE AF Eddy, CR Leonhardt, D Douglass, SR Shamamian, VA Thoms, BD Butler, JE TI Characterization of high density CH4/H-2/Ar plasmas for compound semiconductor etching SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID FILM DEPOSITION; CYCLOTRON; INP AB High density plasmas generated using gas mixtures of methane, hydrogen, and argon are characterized using mass spectrometry, optical emission spectroscopy, and three dimensional Langmuir probing. Such plasmas are commonly used to etch compound semiconductors. In this work we examine the chemical and electrical properties of the flux to the region where substrates art: placed during processing. The dominant species in the flux are identified as II, H+, CH3, CH3+, Ar, and ArH+. Plasma parameters in the source region include electron temperatures of 4-9 eV, plasma densities of 1-5 x 10(11) cm(-3), and plasma potentials of 24-44 V as process conditions art: varied. These parameters are considerably reduced in the process region of the plasma to electron temperatures of 2-6 eV, plasma densities of 1 x 10(9) to 2.5 x 10(10) cm(-3), and plasma potentials of 3-14 V. Mass and optical emission spectral data are correlated to Langmuir probe results and the effects of varying process conditions on plasma properties are presented and discussed. (C) 1999 American Vacuum Society. [S0734-2101(99)02303-9]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Eddy, CR (reprint author), Boston Univ, Dept Elect & Comp Engn, 8 St Marys St, Boston, MA 02215 USA. RI Butler, James/B-7965-2008 OI Butler, James/0000-0002-4794-7176 NR 16 TC 11 Z9 11 U1 2 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1999 VL 17 IS 3 BP 780 EP 792 DI 10.1116/1.581695 PG 13 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 197BD UT WOS:000080344000017 ER PT J AU Boos, JB Bennett, BR Kruppa, W Park, D Mittereder, J Bass, R Twigg, ME AF Boos, JB Bennett, BR Kruppa, W Park, D Mittereder, J Bass, R Twigg, ME TI Ohmic contacts in AlSb InAs high electron mobility transistors for low-voltage operation SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID ALSB/INAS HEMTS; IMPACT IONIZATION; HFETS; GE AB We report on the fabrication and characteristics of Pd/Pt/Au ohmic contacts that have been used in AlSb/InAs high electron mobility transistors (HEMTs) with low access resistance. The metalization exhibits minimal in-diffusion and a contact resistance of 0.08 Omega mm after a 175 degrees C hot-plate heat treatment. By comparison, AuGe/Ni/Pt/Au ohmic contact metalizations formed using a 300 degrees C rapid thermal anneal exhibit a contact resistance of 0.11 Omega mm, but with considerable Au in-diffusion. Using the Pd/Pt/Au contact, 0.6 mu m gate-length AlSb/InAs HEMTs exhibit a low-field source-drain resistance of 0.47 Omega mm and a transconductance above 1 S/mm. After removal of the gate bonding pad capacitance from an equivalent circuit, an f(T)L(g) product of 38 GHz mu m is obtained at V-DS = 0.4 V. HEMTs with a 60 nm gate length exhibit a low-field source-drain resistance of 0.35 Omega mm and a measured f(T) of 90 GHz at a drain voltage of only 100 mV. These f(T)L(g) and f(T) values are the highest reported for any field effect transistor at these drain voltages. C1 USN, Res Lab, Washington, DC 20375 USA. RP Boos, JB (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Bennett, Brian/A-8850-2008 OI Bennett, Brian/0000-0002-2437-4213 NR 16 TC 42 Z9 42 U1 0 U2 9 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 1999 VL 17 IS 3 BP 1022 EP 1027 DI 10.1116/1.590687 PG 6 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 206AD UT WOS:000080853100021 ER PT J AU Cherrier, J Bauer, JE Druffel, ERM Coffin, RB Chanton, JP AF Cherrier, J Bauer, JE Druffel, ERM Coffin, RB Chanton, JP TI Radiocarbon in marine bacteria: Evidence for the ages of assimilated carbon SO LIMNOLOGY AND OCEANOGRAPHY LA English DT Article ID DISSOLVED ORGANIC-CARBON; SARGASSO-SEA; ESTUARINE BACTERIA; PACIFIC-OCEAN; MATTER; BACTERIOPLANKTON; TURNOVER; GROWTH; BLOOM; DNA AB It is generally accepted that marine bacteria utilize labile, recently produced components of bulk dissolved organic matter. This interpretation is based largely on indirect measurements using model compounds and plankton-derived organic matter. Here, we present an assessment of the relative proportions of modem and older dissolved organic carbon (DOC) utilized by marine bacteria. Bacterial nucleic acids were collected from both estuarine (Santa Rosa Sound, FL) and open-ocean (eastern North Pacific) sites, and the natural radiocarbon signatures of the nucleic acid carbon in both systems were determined. Bacterial nucleic acids from Santa Rosa Sound were significantly enriched in radiocarbon with respect to the bulk DOC and were similar to the radiocarbon signature of atmospheric CO2 at the time of sampling, indicating that these bacteria exclusively assimilate a modem component of the estuarine bulk DOG. In contrast, bacterial nucleic acids from the oceanic site were enriched in C-14 relative to the bulk DOC but depleted in C-14 with respect to modem surface dissolved inorganic carbon (DIC) and suspended particulate organic carbon (POCsusp). This suggests that open-ocean bacteria assimilate both modem and older components of DOG. The distinct radiocarbon signatures of the nucleic acids at these two sites (i.e., +120 +/- 17% estuarine vs. -34 +/- 24% oceanic) demonstrate that natural C-14 abundance measurements of bacterial biomarkers are a powerful tool for investigations of carbon cycling through microbial communities in different aquatic systems. C1 Florida A&M Univ, Inst Environm Sci, Tallahassee, FL 32307 USA. Coll William & Mary, Sch Marine Sci, Gloucester Point, VA 23062 USA. Univ Calif Irvine, Dept Earth Syst Sci, Irvine, CA 92697 USA. USN, Res Lab, Washington, DC 20375 USA. Florida State Univ, Dept Oceanog, Tallahassee, FL 32306 USA. RP Cherrier, J (reprint author), Florida A&M Univ, Inst Environm Sci, Tallahassee, FL 32307 USA. NR 40 TC 67 Z9 69 U1 0 U2 13 PU AMER SOC LIMNOLOGY OCEANOGRAPHY PI WACO PA 5400 BOSQUE BLVD, STE 680, WACO, TX 76710-4446 USA SN 0024-3590 J9 LIMNOL OCEANOGR JI Limnol. Oceanogr. PD MAY PY 1999 VL 44 IS 3 BP 730 EP 736 PG 7 WC Limnology; Oceanography SC Marine & Freshwater Biology; Oceanography GA 196UQ UT WOS:000080326300028 ER PT J AU Gordis, JH AF Gordis, JH TI Artificial boundary conditions for model updating and damage detection SO MECHANICAL SYSTEMS AND SIGNAL PROCESSING LA English DT Article AB The updating of finite-element models commonly makes use of measured modal parameters. The number of modal parameters measured in a typical modal test is small, while the number of model parameters to be adjusted can be large. In this paper, it is shown that the natural frequencies for the structure under a variety of boundary conditions are available from any square, spatially incomplete frequency response function data, without any actual physical alteration of the boundary conditions, hence the term 'artificial boundary conditions'. This approach can provide potentially a large number of additional and distinct mode frequencies from the same modal test. The simplest example of this approach is that the driving-point antiresonance frequencies correspond to the natural frequencies obtained from the structure with the driving-point degree of freedom constrained to ground. This result is developed generally for multiple measured points, and is shown to be related to previous results concerning omitted coordinate systems and spatially incomplete test data. The approach is applied to sensitivity-based model updating and damage detection. (C) 1999 Academic Press. C1 USN, Postgrad Sch, Dept Mech Engn Code ME Go, Monterey, CA 93943 USA. RP Gordis, JH (reprint author), USN, Postgrad Sch, Dept Mech Engn Code ME Go, Code ME-Go, Monterey, CA 93943 USA. NR 6 TC 16 Z9 17 U1 0 U2 2 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0888-3270 J9 MECH SYST SIGNAL PR JI Mech. Syst. Signal Proc. PD MAY PY 1999 VL 13 IS 3 BP 437 EP 448 DI 10.1006/mssp.1998.0192 PG 12 WC Engineering, Mechanical SC Engineering GA 197HL UT WOS:000080359300006 ER PT J AU Genfa, Z Dasgupta, PK Frick, GM Hoppel, WA AF Genfa, Z Dasgupta, PK Frick, GM Hoppel, WA TI Airship measurements of hydrogen peroxide and related parameters in the marine atmosphere along the western US coast SO MICROCHEMICAL JOURNAL LA English DT Article ID NORTHEASTERN UNITED-STATES; NORTH-CAROLINA; LOWER TROPOSPHERE; GAS-PHASE; OZONE; CLOUD; WATER; DISTRIBUTIONS; SUMMER; H2O2 AB Hydrogen peroxide remains a key species of interest, in both the polluted and the unpolluted atmosphere. While many studies exist, the vertical distribution of H2O2 in the marine atmosphere has never been reported. This paper reports data for gaseous H2O2, O-3, and SO2 and meteorological parameters measured from an airship along the Oregon and Northern California coast during June 1-28, 1994. Daytime H2O2 levels ranged from 0.064 to 0.505 ppbv, with the mean value being 0.175 +/- 0.077 ppbv. Typically, H2O2 levels generally increase with increasing O-3, temperature, flight altitude, and UV Bur. Conversely, a strong negative correlation with relative humidity is observed. Negative correlations with SO2 are also observed if significant concentrations are present, as in plumes. However, in a fresh plume from a fossil fuel-burning ship, nonzero H2O2 concentrations persist. The vertical profile of H2O2 shows a maximum that generally occurs above the top of the marine boundary layer, at an altitude up to 200-300 m above thr top of the marine boundary layer. (C) 1999 Academic Press. C1 Texas Tech Univ, Dept Chem & Biochem, Lubbock, TX 79409 USA. Naval Res Lab, Remote Sensing Div, Washington, DC USA. RP Dasgupta, PK (reprint author), Texas Tech Univ, Dept Chem & Biochem, Lubbock, TX 79409 USA. NR 27 TC 6 Z9 6 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0026-265X J9 MICROCHEM J JI Microchem J. PD MAY PY 1999 VL 62 IS 1 BP 99 EP 113 DI 10.1006/mchj.1999.1715 PG 15 WC Chemistry, Analytical SC Chemistry GA 192GH UT WOS:000080069800010 ER PT J AU Barrett, TL Smith, KJ Williams, J Corner, SW Hodge, JJ Skelton, HG AF Barrett, TL Smith, KJ Williams, J Corner, SW Hodge, JJ Skelton, HG TI Immunohistochemical staining for Ber-EP4, p53, proliferating cell nuclear antigen, Ki-67, bcl-2, CD34, and factor XIIIa in nevus sebaceus SO MODERN PATHOLOGY LA English DT Article DE basal cell carcinoma; bcl-2; CD34; Ki-67; nevus sebaceus; p53 ID SONIC HEDGEHOG; NORMAL SKIN; EXPRESSION; CARCINOMA; PROTEIN; PCNA; CYCLIN; TRICHOEPITHELIOMA; NEOPLASMS; JADASSOHN AB Increased expression of p53 has been found in the majority of basal cell carcinomas (BCCs). The pattern and intensity of this staining, as well as staining for proliferation antigens, seems to correlate with behavior of histologic subtypes of BCC. Nevus sebaceus CNS) is considered a hamartoma Multiple epithelial neoplasms do arise in NS, and, rarely, they show an aggressive biologic behavior. Significant numbers of these neoplasms, however, have areas of basaloid hyperplasia that are often reported as BCC. Although morphologically similar to BCC, the mechanism underlying the development of these areas has not been investigated, so we sought to evaluate the expression of Ber-EP4, p53, proliferating cell nuclear antigen, Ki-67, bcl-2, Factor XIIIa, and CD34 in areas showing basaloid hyperplasia, arising in NS. We performed immunohistochemical stains for Ber-EP4, p53, proliferating cell nuclear antigen, Ki-67, bcl-2, Factor XIIIa, and CD34 on seven cases of NS with areas of basaloid hyperplasia All of the eight cases of NS showed diffuse positive membrane staining for Ber-EP4 and negative nuclear staining for p53. Proliferating cell nuclear antigen and Ki-67 staining was only slightly increased in the areas of basaloid hyperplasia, compared with the surrounding epidermis and with areas of the epidermis peripheral to the hamartomatous proliferation, and bcl-2 was only focally positive. Factor XIIIa-positive cells and CD34-positive vascular endothelial cells were increased within the subjacent dermis, a pattern suggestive of follicular differentiation. Our findings suggest that even though areas of basaloid hyperplasia in NS are morphologically similar to BCC, they are induced by different stimulatory and molecular mechanisms. These different mechanisms result in expression of immunohistochemical markers more characteristic of benign follicular tumors than of BCC. C1 USN, Med Ctr, San Diego, CA USA. USN, Med Ctr, Bethesda, MD 20814 USA. Lab Corp Amer, Herndon, VA USA. RP Smith, KJ (reprint author), Natl Naval Med Ctr, Dept Dermatol, 8901 Wisconsin Ave, Bethesda, MD 20889 USA. NR 31 TC 15 Z9 15 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0893-3952 J9 MODERN PATHOL JI Mod. Pathol. PD MAY PY 1999 VL 12 IS 5 BP 450 EP 455 PG 6 WC Pathology SC Pathology GA 197CK UT WOS:000080346900003 PM 10349981 ER PT J AU McCluskie, MJ Millan, CLB Gramzinski, RA Robinson, HL Santoro, JC Fuller, JT Widera, G Haynes, JR Purcell, RH Davis, HL AF McCluskie, MJ Millan, CLB Gramzinski, RA Robinson, HL Santoro, JC Fuller, JT Widera, G Haynes, JR Purcell, RH Davis, HL TI Route and method of delivery of DNA vaccine influence immune responses in mice and non-human primates SO MOLECULAR MEDICINE LA English DT Article ID B SURFACE-ANTIGEN; CYTOTOXIC T-LYMPHOCYTES; DIRECT GENE-TRANSFER; IMMUNODEFICIENCY-VIRUS TYPE-1; NUCLEIC-ACID IMMUNIZATION; IN-VIVO TRANSFECTION; MARROW-DERIVED CELLS; HERPES-SIMPLEX-VIRUS; PLASMID DNA; HEPATITIS-B AB Background: In spite of the large number of studies that have evaluated DNA-based immunization, few have directly compared the immune responses generated by different routes of immunization, particularly in non-human primates. Here we examine the ability of a hepatitis B surface antigen (HBsAg)-encoding plasmid to induce immune responses in mice and non-human primates (rhesus monkeys: Macaca mulatta) after delivery by a number of routes. Materials and Methods: Eight different injected [intraperitoneal (IP), intradermal (ID), intravenous (IV), intramuscular (IM), intraperineal (IPER), subcutaneous (SC), sublingual (SL), vaginal wall (VW)I and six noninjected [intranasal inhalation (WH), intranasal instillation (INS), intrarectal (IR), intravaginal (IVAG), ocular (Oc), oral feeding (oral)] routes and the gene gun (GG) were used to deliver HBsAg-expressing plasmid DNA to BALB/c mice. Sera were assessed for HBsAg-specific antibodies (anti-HBs, IgG, IgG1, IgG2a) and cytotoxic T lymphocyte (CTL) activity measured. Three of the most commonly used routes (LM, ID, GG) were compared in rhesus monkeys, also using HBsAg-expressing vectors. Monkeys were immunized with short (0-, 4- and 8-week) or long (0-, 12- and 24-week) intervals between boosts, and in the case of GG, also with different doses, and their sera were assessed for anti-HBs. Results: In one study, anti-HBs were detected in plasma of mice treated by five of eight of the injected and none of the six noninjected routes. The highest levels of anti-HBs were induced by IM and IV injections, although significant titers were also obtained with SL and ID. Each of these routes also induced CTL, as did IPER and VW and one noninjected route (INH) that failed to induce antibodies. In a second study, GG (1.6 mu g) was compared to ID and TM (100 mu g) delivery. Significant titers were obtained by all routes after only one boost, with the highest levels detected by IM. Delivery to the skin by GG induced exclusively IgG1 antibodies (Th2-like) at 4 weeks and only very low IgG2a levels at later times; ID-immunized mice bad predominantly IgG1 at 4 weeks and this changed to mixed IgG1/IgG2a over time. Responses with IM injection (in the leg or tongue) were predominantly IgG2a (Th1-like) at all times. IV injection gave mixed IgG1/IgG2a responses. In monkeys, in the first experiment, 1 mg DNA IM or ID at 0, 4, and 8 weeks gave equivalent anti-MB titers and 0.4 mu g at the same times by GG induced lower titers. In the second experiment, 1 mg DNA IM or ID, or 3.2 mu g by GG, at 0, 12, and 24 weeks, gave anti-MR values in the hierarchy of GG > IM > ID. Furthermore, high titers were retained after a single immunization in mice but fell off overtime in the monkeys, even after boost. Conclusions: Route of administration of plasmid DNA vaccines influences the strength and nature of immune responses in mice and non-human primates. However, the results in mice were not always predictive of those in monkeys and this is likely true for humans as well. Optimal dose and immunization schedule will most likely vary between species. It is not clear whether results in non-human primates will be predictive of results in humans, thus additional studies are required. C1 Ottawa Hosp, Loeb Hlth Res Inst, Ottawa, ON, Canada. Univ Ottawa, Fac Med, Dept Cellular & Mol Med, Ottawa, ON, Canada. USN, Med Res Inst, Malaria Program, Rockville, MD 20852 USA. Univ Massachusetts, Sch Med, Dept Pathol, Worcester, MA USA. PowerJect Vaccines, Madison, WI USA. NIAID, Infect Dis Lab, NIH, Bethesda, MD 20892 USA. Univ Ottawa, Fac Med, Dept Microbiol Immunol & Biochem, Ottawa, ON, Canada. Univ Ottawa, Sch Rehabil Sci, Fac Hlth Sci, Ottawa, ON, Canada. RP Davis, HL (reprint author), Loeb Hlth Res Inst, 725 Parkdale Ave, Ottawa, ON K1Y 4E9, Canada. FU NIAID NIH HHS [N01-AI-52705] NR 84 TC 132 Z9 140 U1 0 U2 12 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1076-1551 J9 MOL MED JI Mol. Med. PD MAY PY 1999 VL 5 IS 5 BP 287 EP 300 PG 14 WC Biochemistry & Molecular Biology; Cell Biology; Medicine, Research & Experimental SC Biochemistry & Molecular Biology; Cell Biology; Research & Experimental Medicine GA 217JB UT WOS:000081495300002 PM 10390545 ER PT J AU Ruggiero, FH Sashegyi, KD Lipton, AE Madala, RV Raman, S AF Ruggiero, FH Sashegyi, KD Lipton, AE Madala, RV Raman, S TI Coupled assimilation of geostationary satellite sounder data into a mesoscale model using the Bratseth analysis approach SO MONTHLY WEATHER REVIEW LA English DT Article ID OBJECTIVE ANALYSIS SCHEME; 4-DIMENSIONAL DATA ASSIMILATION; ANALYSIS SYSTEM; RETRIEVAL; GALE; RADIANCES; WEATHER AB A satellite-model coupled procedure for assimilating geostationary satellite sounder data was adapted to a mesoscale analysis and forecast system jointly developed by the Naval Research Laboratory and the Air Force Research Laboratory. The coupled procedure involves the use of the model output fields as the first guess for the thermodynamic retrievals. Atmospheric thermodynamic profiles and ground temperatures were retrieved from observed radiances of the VISSR Atmospheric Sounder (VAS) on board the Geostationary Operational Environmental Satellite. The successive corrections objective analysis scheme in the mesoscale analysis and forecast system was modified to consider the horizontal spatial correlation of the satellite data. The procedure was tested using a wintertime case from the 1986 Genesis of Atlantic Lows Experiment project. The retrievals generated by the coupled method were modestly improved relative to independent stand-alone retrievals. Coupled analyses and forecasts of temperature and moisture fields compared favorably to forecasts from a control run without the VAS assimilation. C1 USAF, VSBE, Battlespace Environm Div, Res Lab, Hanscom AFB, MA 01731 USA. USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Ruggiero, FH (reprint author), USAF, VSBE, Battlespace Environm Div, Res Lab, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. EM ruggiero@arcdbs.plh.af.mil NR 50 TC 11 Z9 11 U1 0 U2 0 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 MAY PY 1999 VL 127 IS 5 BP 802 EP 821 DI 10.1175/1520-0493(1999)127<0802:CAOGSS>2.0.CO;2 PG 20 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 194RW UT WOS:000080208200013 ER PT J AU Vaughters, DS Olson, TM Gill, SE Wagner, LA AF Vaughters, DS Olson, TM Gill, SE Wagner, LA TI It's in the bag: Submarine plastic waste management SO NAVAL ENGINEERS JOURNAL LA English DT Article AB The National Defense Authorization Act for fiscal year 1994 prohibits the discharge of plastic waste from U.S. Navy submarines after December 31, 2008. This will require the Navy submarine community to develop an effective method for handling and storing plastic waste aboard for eventual return to port. Paramount objectives include volume reduction, sanitary packaging of the waste, and locating suitable storage spaces on each submarine class. Carderock Division of the Naval Surface Warfare Center conducted a review of all potential plastic waste processing options. The submarine trash compactor unit and Navy odor barrier bags were selected for detailed investigation. A process was developed whereby plastic waste was compacted directly into high strength odor barrier bags called submarine plastic waste containment bags. Potential storage locations Sor compacted plastic waste have been identified aboard the Los Angeles (SSN 688), Ohio (SSBN 726), and Seawolf (SSN 21) Classes. Plastic Waste Management Demonstrations will be conducted on each submarine class to evaluate the suitability and effectiveness of the proposed plastic waste management solutions. C1 Naval Surface Warfare Ctr, Carderock Div, Solid Waste Management Branch, Submarine Solid Waste Management Program, W Bethesda, MD USA. RP Vaughters, DS (reprint author), Naval Surface Warfare Ctr, Carderock Div, Solid Waste Management Branch, Submarine Solid Waste Management Program, W Bethesda, MD USA. NR 23 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 USA SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1999 VL 111 IS 3 BP 85 EP 95 PG 11 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA 195JT UT WOS:000080247800007 ER PT J AU Schuh, RL AF Schuh, RL TI Pollution Prevention COTS equipment: Lessons learned and return on investment SO NAVAL ENGINEERS JOURNAL LA English DT Article AB The goal of the Pollution Prevention (PZ) Afloat Program is source reduction of hazardous materials (HM) used in standard shipboard maintenance and other afloat activities. Executive Order 12856 requires federal facilities to reduce the release of hazardous substances by 50 percent by 1999 compared to a 1994 baseline. Studies show that up to 70 percent of the hazardous waste processed at Navy facilities is obtained from HM off-loads from ships. The P2 Afloat Team is achieving source reduction goals by identifying, assessing, and implementing source reduction opportunities aboard ships, and focusing on the direct use or minimal reengineering of commercial-off-the-shell products. There have been many challenges and lessons learned during research, procurement, test and evaluation, installation, and return on investment analyses of P2 Afloat equipment. Applying these lessons beamed regarding pollution prevention in the maritime environment is essential in order to meet the challenges of the Fleet in the new millennium. C1 USN, Ctr Surface Warfare, Caderock Div, Pollut Prevent Afloat Team, W Bethesda, MD USA. RP Schuh, RL (reprint author), USN, Ctr Surface Warfare, Caderock Div, Pollut Prevent Afloat Team, W Bethesda, MD 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 USA SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1999 VL 111 IS 3 BP 279 EP 284 PG 6 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA 195JT UT WOS:000080247800021 ER PT J AU Jenkins, AA AF Jenkins, AA TI Analysis of lateral maneuver-induced lift loss of navy fighter attack aircraft during approach to carrier SO NAVAL ENGINEERS JOURNAL LA English DT Article AB The purpose of this analysis was to provide guidance to designers of future tactical Navy aircraft on one aspect of carrier suitability that has contributed to the operational success of the F-14 and F/A-18 in carrier operations. Specifically the ability of both of these aircraft to perform aggressive lateral maneuvers to capture desired glide path, without excessive altitude loss, has contributed to the favorable carrier suitability characteristics of each aircraft. The intent of this analysis was to quantify lift and altitude loss for the F-14 and F/A-18 due to lateral maneuvers in the lineup correction task, and determine the causes and components of the lift loss. A secondary intent was to determine whether the amount of lift loss due to lateral maneuvers was a good indicator of an aircraft's ability to execute precise flight path control with minimum pilot workload. Twenty-six offline simulations of F-14B and F/A-18C aircraft, conducted at Manned Flight Simulator at the Naval Air Warfare Center Aircraft Division in Patuxent River, MD, provided the raw data for the analysis. Results and conclusions on the causes and components of lift loss and subsequent altitude loss associated with the 26 simulations were drawn, and where applicable, comparisons between F-14 and F/A-18 were made. C1 USN, Air Syst Command, Flight Dynam Branch, Patuxent River, MD USA. RP Jenkins, AA (reprint author), USN, Air Syst Command, Flight Dynam Branch, Patuxent River, MD USA. NR 5 TC 0 Z9 0 U1 1 U2 1 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 USA SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD MAY PY 1999 VL 111 IS 3 BP 371 EP 394 PG 24 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA 195JT UT WOS:000080247800029 ER PT J AU Gherman, RB McBrayer, S Tichenor, J Wing, DA AF Gherman, RB McBrayer, S Tichenor, J Wing, DA TI Placenta increta complicating first-trimester D & C SO OBSTETRICS AND GYNECOLOGY LA English DT Article C1 USN, Med Ctr, Dept Obstet & Gynecol, Div Maternal Fetal Med, Portsmouth, VA 23708 USA. Univ So Calif, Sch Med, Dept Obstet & Gynecol, Div Maternal Fetal Med, Los Angeles, CA USA. RP Gherman, RB (reprint author), USN, Med Ctr, Dept Obstet & Gynecol, Div Maternal Fetal Med, Portsmouth, VA 23708 USA. NR 4 TC 12 Z9 13 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0029-7844 J9 OBSTET GYNECOL JI Obstet. Gynecol. PD MAY PY 1999 VL 93 IS 5 SU S BP 845 EP 845 DI 10.1016/S0029-7844(98)00315-9 PN 2 PG 1 WC Obstetrics & Gynecology SC Obstetrics & Gynecology GA 192PF UT WOS:000080087000024 PM 10912421 ER PT J AU Bogdanov, YA Sagalevitch, AM Vogt, PR Mienert, Y Sundvor, E Krane, K Lein, AY Egorov, AV Pepesypkin, VI Cherkashev, GA Gebruk, AV Ginsburg, GD Voitov, DT AF Bogdanov, YA Sagalevitch, AM Vogt, PR Mienert, Y Sundvor, E Krane, K Lein, AY Egorov, AV Pepesypkin, VI Cherkashev, GA Gebruk, AV Ginsburg, GD Voitov, DT TI The Haakon Mosby mud volcano in the Norwegian Sea: Results of comprehensive investigations with submersibles SO OKEANOLOGIYA LA Russian DT Article ID TROUGH-MOUTH-FAN; DEPOSITS AB Multi disciplinary oceanological investigations of the Haakon Mosby mud volcano were carried out on board of the R/V "Akademik Mstislav Keldysh" in summer 1998. Identification, description and sampling of all main structures of the volcano and investigation of the composition and distribution of biota were carried out from two "Mir" submersibles. The information about the composition of bottom sediments, pore waters, content and composition of hydrocarbons in bottom sediments and seawater was obtained during this expedition. C1 PP Shirshov Oceanol Inst, Moscow, Russia. USN, Res Lab, Div Marine Sci, Washington, DC 20375 USA. Kiel Marine Sci Res Ctr, Kiel, Germany. Univ Bergen, Seismol Observ, Bergen, Norway. CUNY Hunter Coll, New York, NY 10021 USA. All Russian Ocean Geol Res Inst, St Petersburg, Russia. RP Bogdanov, YA (reprint author), PP Shirshov Oceanol Inst, Moscow, Russia. RI Cherkashov, Georgy/N-6949-2013 OI Cherkashov, Georgy/0000-0002-9870-6428 NR 6 TC 7 Z9 8 U1 1 U2 1 PU MEZHDUNARODNAYA KNIGA PI MOSCOW PA 39 DIMITROVA UL., 113095 MOSCOW, RUSSIA SN 0030-1574 J9 OKEANOLOGIYA+ JI Okeanologiya PD MAY-JUN PY 1999 VL 39 IS 3 BP 412 EP 419 PG 8 WC Oceanography SC Oceanography GA 224KA UT WOS:000081896000012 ER PT J AU Lattimore, MR Kaupp, S Schallhorn, S Lewis, R AF Lattimore, MR Kaupp, S Schallhorn, S Lewis, R TI Orbscan pachymetry - Implications of a repeated measures and diurnal variation analysis SO OPHTHALMOLOGY LA English DT Article; Proceedings Paper CT Annual Meeting of the American-Academy-of-Optometry CY DEC, 1997 CL SAN ANTONIO, TEXAS SP Amer Acad Optometry ID CORNEAL THICKNESS; RADIAL KERATOTOMY; INTRAOCULAR-PRESSURE; TOPOGRAPHY AB Introduction: Corneal thickness changes reflect alterations in hydration and metabolism. Ultrasound pachymetry determinations may be adversely influenced by fluctuations in tissue hydration, whereas optical systems are apparently unaffected by these fluxes, A recently marketed, optical-based, topographic mapping system (Orbscan; Orbtek, Inc.) uses anterior and posterior corneal surface data to calculate corneal thickness. Objective: This new instrumentation presents as a potentially useful pachymetry tool for evaluation of corneas under hydration flux or challenge (e.g., postphotorefractive keratectomy [PRK] healing studies) and was therefore evaluated for accuracy and variability. Measurements: Three calibrated standards were measured in repeated fashion. Additionally, 1 test subject was measured 30 times in 1 day (5 measurements each at 8:00, 9:30, and 11:00 AM and at 1:00, 2:30, and 4:00 PM). Corresponding measurements were made at 8:00 and 11:00 AM and at 4:00 PM On 3 Separate days to assess repeatability. Grouped data from 18 volunteer subjects were compared to the data of the test subject as well, Results: Pachymetry accuracy on a calibrated standard was determined to be +/-2 mu m (standard deviation, n = 12), Repeated measures on the subject demonstrated a mean standard deviation of 9.08 mu m for 750 thickness data points across the central 7 mm of the cornea; peripheral measurement points exhibited progressively greater variability than at the apex (analysis of variance; P < 0.0001), A plot of thickness by corneal location and time of day exhibited a diurnal pattern, with the peripheral cornea exhibiting progressively greater thickness changes than the central cornea (two-way analysis of variance; P < 0.00001). The data significantly correlated across days when all times of day were considered (r = 0.999). However, thickness values obtained at 8:00 AM were significantly different across days (t test; P < 0.0002), The subject's data correlated very well (r = 0.9996) with the grouped volunteer data. Conclusions: These data show this system to be useful in corneal research and in clinical settings. The data confirm early morning pachymetry to be highly variable. Additionally, the data not only indicate a diurnal variation of corneal hydration over time, but also imply the presence of a diurnal-based hydration gradient across the peripheral cornea, both of which can have significance for PRK, since excimer tissue ablation effectiveness is influenced by tissue hydration. C1 USN, Hlth Res Ctr, San Diego, CA 92152 USA. USN, Med Ctr, San Diego, CA 92152 USA. RP Lattimore, MR (reprint author), USA, Aeromed Lab, Aircrew Hlth & Performance Div, POB 620577, Ft Rucker, AL 36362 USA. NR 15 TC 123 Z9 131 U1 0 U2 4 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0161-6420 J9 OPHTHALMOLOGY JI Ophthalmology PD MAY PY 1999 VL 106 IS 5 BP 977 EP 981 DI 10.1016/S0161-6420(99)00519-9 PG 5 WC Ophthalmology SC Ophthalmology GA 192TN UT WOS:000080095500036 PM 10328399 ER PT J AU Choplin, NT Schallhorn, SC AF Choplin, NT Schallhorn, SC TI The effect of excimer laser photorefractive keratectomy for myopia on nerve fiber layer thickness measurements as determined by scanning laser polarimetry SO OPHTHALMOLOGY LA English DT Article; Proceedings Paper CT Annual Meeting of the Association-for-Research-in-Vision-and-Ophthalmology CY MAY 12-14, 1998 CL FT LAUDERDALE, FLORIDA SP Assoc Res Vis & Ophthalmol ID OCULAR HYPERTENSION; GLAUCOMA AB Objective: Scanning laser polarimetry measures the retardation of polarized laser light as it passes through the birefringent retinal nerve fiber layer (RNFL), Because retardation is directly proportional to the number of retinal nerve fibers, indirect measurements of the RNFL thickness are obtained, A fixed compensatory mechanism is used to correct for retardation attributed to birefringence in the cornea and anterior segment, Excimer laser photorefractive keratectomy (PRK) corrects myopia by ablating tissue from the cornea, This study was conducted to determine the effect of this ablation on RNFL measurements. Design: Prospective comparative case series. Participants: Eighteen patients. Methods: Patients undergoing PRK had RNFL measurements performed with the GDx Nerve Fiber Analyzer (Laser Diagnostic Technologies, San Diego, CA), a scanning laser polarimeter, in both eyes before and 90 days after PRK in the first eye. Main Outcome Measures: Fourteen different GDx parameters were analyzed for statistically significant differences preoperatively and 3 months postoperatively in the treated and untreated eye using Hotelling's T-squared generalized means test. Results: Eighteen patients underwent PRK in the nondominant eye first. Preoperative refractions averaged -3.8 +/- 1.6 diopters (D), with an average correction of 3.4 +/- 1.9 D, corresponding to 49.7 +/- 20.5 microns of ablation. There were no statistically significant preoperative differences between the fellow eyes in refractive error (P = 0.65). Postoperatively, there were no statistically significant changes in any GDx parameter in the treated eye compared with the untreated control eye (P = 0.21), Conclusions: Excimer laser PRK for moderate myopia has no significant effect on RNFL thickness measurements as determined by scanning laser polarimetry. C1 USN, Med Ctr, Dept Clin Invest, San Diego, CA 92134 USA. USN, Med Ctr, Dept Ophthalmol, San Diego, CA 92134 USA. RP Choplin, NT (reprint author), USN, Med Ctr, Dept Clin Invest, 34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 12 TC 32 Z9 35 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0161-6420 J9 OPHTHALMOLOGY JI Ophthalmology PD MAY PY 1999 VL 106 IS 5 BP 1019 EP 1023 DI 10.1016/S0161-6420(99)00527-8 PG 5 WC Ophthalmology SC Ophthalmology GA 192TN UT WOS:000080095500045 PM 10328407 ER PT J AU Schuler, JM Scribner, DA AF Schuler, JM Scribner, DA TI Increasing spatial resolution through temporal super-sampling of digital video SO OPTICAL ENGINEERING LA English DT Article DE spatial resolution; resolution enhancement; super-resolution; image restoration AB A general method is outlined to increase the spatial resolution of digital video sequences containing uncontrolled camera motion. This is accomplished by combining multiple frames of video into a composite image of a higher spatial sampling rate than the original video. Fundamental to this technique is the computation of optical flow. This technique has the greatest impact on camera systems where the focal plane array spatially undersamples the projected optical image. Implicit to the technique is the potential trade-off between frame rate, latency, and display resolution in a digital imaging system. (C) 1999 Society of Photo-Optical Instrumentation Engineers. [S0091-3286(99)00505-X]. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. RP Schuler, JM (reprint author), USN, Res Lab, Div Opt Sci, Code 5636,4555 Overlook Ave SW, Washington, DC 20375 USA. NR 7 TC 12 Z9 12 U1 0 U2 1 PU SPIE-INT SOCIETY OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, BELLINGHAM, WA 98225 USA SN 0091-3286 J9 OPT ENG JI Opt. Eng. PD MAY PY 1999 VL 38 IS 5 BP 801 EP 805 DI 10.1117/1.602046 PG 5 WC Optics SC Optics GA 194VU UT WOS:000080215900008 ER PT J AU Hoffer, ME Balough, BJ Kopke, RD Henderson, J DeCicco, M Wester, DC O'Leary, MJ Balaban, C AF Hoffer, ME Balough, BJ Kopke, RD Henderson, J DeCicco, M Wester, DC O'Leary, MJ Balaban, C TI Morphologic changes in the inner ear of Chinchilla laniger after middle ear administration of gentamicin in a sustained-release vehicle SO OTOLARYNGOLOGY-HEAD AND NECK SURGERY LA English DT Article; Proceedings Paper CT 101st Annual Meeting of the American-Academy-of-Otolaryngology-Head-and-Neck-Surgery CY SEP 07-10, 1997 CL SAN FRANCISCO, CALIFORNIA SP Amer Acad Otolaryngol Head & Neck Surg ID INTRATYMPANIC GENTAMICIN; MENIERES-DISEASE AB The use of transtympanic gentamicin has become a popular method of treating Meniere's disease; nevertheless, many questions still remain regarding this therapy. Until investigators can control the exact amount of medicine that is administered to the ear and have an understanding of the kinetics of gentamicin, therapy will continue to rely on empirical data. Previously we described the use of a fibrin-based sustained-release vehicle impregnated with gentamicin in the middle ears of chinchillas. With this model a kinetics curve of gentamicin was defined. The inner ears of these animals were submitted for immunohistochemical and histologic analysis. We discuss the ultrastructural changes seen and correlate this to our kinetics data. We also examine measurement of hair cell damage with heat shock protein levels. By better understanding the actions of gentamicin in this animal model, we hope to facilitate safer use of intratympanic medicines in our patient population. C1 USN, Med Ctr, Dept Def Spatial Orientat Ctr, Dept Otolaryngol, San Diego, CA 92134 USA. Univ Pittsburgh, Sch Med, Pittsburgh, PA USA. RP Hoffer, ME (reprint author), USN, Med Ctr, Dept Def Spatial Orientat Ctr, Dept Otolaryngol, San Diego, CA 92134 USA. OI Balaban, Carey/0000-0002-3570-3844 NR 12 TC 23 Z9 24 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0194-5998 J9 OTOLARYNG HEAD NECK JI Otolaryngol. Head Neck Surg. PD MAY PY 1999 VL 120 IS 5 BP 643 EP 648 DI 10.1053/hn.1999.v120.a91762 PG 6 WC Otorhinolaryngology; Surgery SC Otorhinolaryngology; Surgery GA 194EN UT WOS:000080179300005 PM 10229587 ER PT J AU McManaman, J Tam, DA AF McManaman, J Tam, DA TI Gabapentin for self-injurious behavior in Lesch-Nyhan syndrome SO PEDIATRIC NEUROLOGY LA English DT Article ID DISEASE AB Self-injurious behavior is a common clinical problem in children with Lesch-Nyhan syndrome, an X-linked disorder of purine metabolism. This behavior is not observed in other conditions associated with increased serum concentrations of uric acid, hypoxanthine, and xanthine, Various neurotransmitters appear to play a pivotal role in self-injurious behavior. The authors present a patient with Lesch-Nyhan syndrome, whose self-injurious behavior was effectively treated with gabapentin, and discuss possible mechanisms of action. (C) 1999 by Elsevier Science Inc. All rights reserved. C1 USN, Med Ctr, Dept Clin Invest, San Diego, CA 92134 USA. USN, Med Ctr, Dept Pediat, San Diego, CA 92134 USA. Uniformed Serv Univ Hlth Sci, Bethesda, MD USA. RP McManaman, J (reprint author), USN, Med Ctr, Dept Clin Invest, Suite 5,34800 Bob Wilson Dr, San Diego, CA 92134 USA. NR 11 TC 18 Z9 18 U1 1 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0887-8994 J9 PEDIATR NEUROL JI Pediatr. Neurol. PD MAY PY 1999 VL 20 IS 5 BP 381 EP 382 DI 10.1016/S0887-8994(98)00166-0 PG 2 WC Clinical Neurology; Pediatrics SC Neurosciences & Neurology; Pediatrics GA 200UH UT WOS:000080558100008 PM 10371385 ER PT J AU Vobornik, I Gatt, R Schmauder, T Frazer, B Kelley, RJ Kendziora, C Grioni, M Onellion, M Margaritondo, G AF Vobornik, I Gatt, R Schmauder, T Frazer, B Kelley, RJ Kendziora, C Grioni, M Onellion, M Margaritondo, G TI The symmetry of the order parameter in highly overdoped Bi2Sr2CaCu2O8+x SO PHYSICA C LA English DT Article; Proceedings Paper CT 1st Euroconference on Anomalous Complex Superconductors CY SEP 26-OCT 03, 1998 CL AGHIA PELAGIA, GREECE SP Commiss European Union DE symmetry; order parameter; Bi2Sr2CaCu2O8+x ID RESOLVED PHOTOEMISSION SPECTROSCOPY; SUPERCONDUCTING GAP ANISOTROPY AB We report results of an angle-resolved high-resolution photoemission study of strongly overdoped Bi2Sr2CaCu2O8+x single crystals with T-c similar to 60 K. We find a nonzero superconducting (SC) gap along all three high symmetry directions in the Brillouin zone, in contrast with a d-wave scenario of high temperature superconductivity. Our data indicate that both the maximum gap value and the gap anisotropy decrease with overdoping. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Ecole Polytech Fed Lausanne, Inst Phys Appl, CH-1015 Lausanne, Switzerland. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. USN, Res Lab, Washington, DC 20375 USA. RP Vobornik, I (reprint author), Ecole Polytech Fed Lausanne, Inst Phys Appl, CH-1015 Lausanne, Switzerland. EM ivana.vobornik@epfl.ch RI Margaritondo, Giorgio/B-1367-2008; Vobornik, Ivana/B-9463-2015; OI vobornik, ivana/0000-0001-9957-3535 NR 13 TC 15 Z9 15 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY PY 1999 VL 317 BP 589 EP 591 DI 10.1016/S0921-4534(99)00137-9 PG 3 WC Physics, Applied SC Physics GA 211QV UT WOS:000081173100094 ER PT J AU Agassi, D Cullen, JR AF Agassi, D Cullen, JR TI New vortex state in the presence of a long Josephson junction SO PHYSICA C LA English DT Article ID PLANAR DEFECTS; SUPERCONDUCTORS; VORTICES AB It is shown that there are two vortex states for the configuration of an Abrikosov vortex in the presence of a long Josephson junction. One state, dubbed 'conventional', carries one magnetic-flux quantum Phi(0), as does the generating Abrikosov vortex. The second and new vortex state entails in addition to the generating vortex two Josephson vortices with opposite polarity to that of the generating-vortex and its magnetic flux is -Phi(0). As a function of the vortex core and Josephson junction-plane distance, the accompanying pinning potentials are quasi-degenerate in the near proximity to the Josephson junction plane, where the conventional-vortex-state pinning potential is the lower. Conditions facilitating the experimental observation of the new vortex state and a specific signature are briefly discussed. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USN, Carderock Div, Ctr Surface Warfare, Bethesda, MD 20817 USA. RP Agassi, D (reprint author), USN, Carderock Div, Ctr Surface Warfare, Code 68,9500 MacArthur Blvd W, Bethesda, MD 20817 USA. NR 28 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY 1 PY 1999 VL 316 IS 1-2 BP 1 EP 12 DI 10.1016/S0921-4534(99)00198-7 PG 12 WC Physics, Applied SC Physics GA 202BZ UT WOS:000080633400001 ER PT J AU Jackson, K Pederson, M Wang, CZ Ho, KM AF Jackson, K Pederson, M Wang, CZ Ho, KM TI Calculated polarizabilities of intermediate-size Si clusters SO PHYSICAL REVIEW A LA English DT Article ID GENERALIZED GRADIENT APPROXIMATION; SILICON CLUSTERS; SEMICONDUCTOR CLUSTERS; METAL-CLUSTERS; SPECTRA; SOLIDS; RAMAN AB We have used a first-principles, density-functional-based method to calculate the electric polarizabilities and dipole moments for several low-energy geometrics of Si clusters in the size range 10 less than or equal to N less than or equal to 20. The polarizability per atom is found to be a slowly varying, nonmonotonic function of N. Over this size range the polarizability appears to be correlated most strongly to cluster shape and not with either the dipole moment or the highest occupied-lowest unoccupied molecular-orbital gap. The calculations indicate that the polarizability per atom for Si clusters approaches the bulk limit from above as a function of size. [S1050-2947(99)07305-9]. C1 Cent Michigan Univ, Dept Phys, Mt Pleasant, MI 48859 USA. USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. Iowa State Univ Sci & Technol, Ames Lab, US Dept Energy, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames Lab, Dept Phys & Astron, Ames, IA 50011 USA. RP Cent Michigan Univ, Dept Phys, Mt Pleasant, MI 48859 USA. OI Jackson, Koblar/0000-0002-5342-7978 NR 24 TC 64 Z9 64 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 EI 1094-1622 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1999 VL 59 IS 5 BP 3685 EP 3689 DI 10.1103/PhysRevA.59.3685 PG 5 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 197UB UT WOS:000080383100073 ER PT J AU Dolan, K Witt, A Spano, ML Neiman, A Moss, F AF Dolan, K Witt, A Spano, ML Neiman, A Moss, F TI Surrogates for finding unstable periodic, orbits in noisy data sets SO PHYSICAL REVIEW E LA English DT Article ID LOW-DIMENSIONAL DYNAMICS; TIME-SERIES; STOCHASTIC RESONANCE; BISTABLE SYSTEMS; HARMONIC NOISE; CHAOS; NONLINEARITY; BIOLOGY; DRIVEN; TESTS AB Recently, searches for unstable periodic orbits in biological and medical applications have become of interest. The motivations for this research range, in order of ascending complexity, from efforts to understand the dynamics of simple sensory neurons, through speculations regarding neural coding, to the hopeful development of new diagnostic and/or control techniques for cardiac and epileptic pathologies. Biological and medical data are, however, noisy and nonstationary. Findings of unstable periodic orbits in such data thus require convincing assessments of their statistical significance. Such tests are accomplished by comparison with surrogate data files designed to test an appropriate null hypothesis. In this paper we test surrogates generated by three different algorithms against correlated noise as well as stable periodic orbits. One of the surrogates is new, and has been specifically designed to preserve the shape of the attractor. We discuss the suitability of these surrogates and argue that the simple shuffled one correctly tests the appropriate null hypothesis. [S1063-651X(99)00505-X]. C1 Univ Missouri, Ctr Neurodynam, St Louis, MO 63121 USA. Univ Potsdam, Dept Phys, D-14415 Potsdam, Germany. NSWC, Carderock Lab, Bethesda, MD 20817 USA. RP Univ Missouri, Ctr Neurodynam, St Louis, MO 63121 USA. RI Neiman, Alexander/G-2196-2010; Spano, Mark/B-6883-2011 OI Neiman, Alexander/0000-0002-0906-9894; NR 37 TC 39 Z9 39 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0045 EI 2470-0053 J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1999 VL 59 IS 5 BP 5235 EP 5241 DI 10.1103/PhysRevE.59.5235 PN A PG 7 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 197TX UT WOS:000080382700070 PM 11969481 ER PT J AU Kaganovich, D Ting, A Moore, CI Zigler, A Burris, HR Ehrlich, Y Hubbard, R Sprangle, P AF Kaganovich, D Ting, A Moore, CI Zigler, A Burris, HR Ehrlich, Y Hubbard, R Sprangle, P TI High efficiency guiding of terawatt subpicosecond laser pulses in a capillary discharge plasma channel SO PHYSICAL REVIEW E LA English DT Article ID WAVE-GUIDE; HARMONIC-GENERATION; ACCELERATION AB Transmission efficiencies in excess of 75% were obtained;in the optical guiding of subpicosecond, terawatt laser pulses in a 2-cm-long capillary discharge plasma channel at the Naval Research Laboratory. The guided laser beam size at the exit of the channel was measured using far field imaging and Thomson scattering techniques. The guided laser intensity was >1 X 10(17) W/cm(2) at a guided beam diameter of 35 mu m for a propagation length of 22 Rayleigh ranges. There is evidence that the plasma channel extends beyond the ends of the capillary and affects the far field beam structure of the transmitted laser pulse. [S1063-651X(99)51305-6]. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. RP Kaganovich, D (reprint author), Hebrew Univ Jerusalem, IL-91905 Jerusalem, Israel. RI zigler, arie/C-2667-2012 NR 20 TC 40 Z9 40 U1 1 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 MAY PY 1999 VL 59 IS 5 BP R4769 EP R4772 DI 10.1103/PhysRevE.59.R4769 PN A PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 197TX UT WOS:000080382700017 PM 11969516 ER PT J AU Sprangle, P Hafizi, B AF Sprangle, P Hafizi, B TI Guiding and stability of short laser pulses in partially stripped ionizing plasmas SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID X-RAY LASERS; WAKE-FIELD ACCELERATION; FREE-ELECTRON LASER; INJECTED ELECTRONS; RAMAN-SCATTERING; TENUOUS PLASMAS; SELF-MODULATION; MOVING FOCUS; WAVE-GUIDE; INTENSE AB Laser pulse propagation can be strongly influenced by nonlinearity effects (relativistic and/or atomic electrons), ionization processes, and finite pulse length effects. In this paper these processes are included in the analysis of the propagation and stability of intense laser pulses in plasmas. An envelope equation, which includes ionization and nonlinear effects, is derived and the spot size is found to be unstable to an ionization-modulation instability. Introducing a quasiparaxial approximation to the wave equation, a pair of coupled envelope-power equations including finite pulse length effects, as well as nonlinearities, is derived and analyzed. In addition, short laser pulses propagating in plasma channels are found to undergo an envelope modulation that is always damped in the front and initially grows in the back of the pulse. Finite pulse length effects are also shown to modify nonlinear focusing processes. Finally, it is shown that, in a partially stripped plasma, the bound electrons can significantly alter the stability of laser pulses. In the presence of both free and bound electrons, an atomic modulation instability develops that can have a growth rate substantially higher than either the conventional relativistic modulational instability or the forward Raman instability. The filamentation instability is shown to be enhanced by bound electrons while the backward Raman instability is unaffected. An example of laser wakefield acceleration to electron energies greater than 2.5 GeV in a plasma channel is described. (C) 1999 American Institute of Physics. [S1070-664X(99)91005-4]. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Icarus Res Inc, Bethesda, MD 20824 USA. RP Sprangle, P (reprint author), USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. NR 61 TC 22 Z9 22 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1683 EP 1689 DI 10.1063/1.873426 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500002 ER PT J AU Zonca, F Chen, L Dong, JQ Santoro, RA AF Zonca, F Chen, L Dong, JQ Santoro, RA TI Existence of ion temperature gradient driven shear Alfven instabilities in tokamaks SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID KINETIC BALLOONING MODES; ENERGETIC PARTICLES AB The existence of unstable ion temperature gradient driven Alfven eigenmodes (AITG) is demonstrated in tokamak plasmas, which are ideally stable with respect to magnetohydrodynamics (MHD). Conditions for the destabilization of such modes are quantitatively discussed on the basis of numerical solutions of a set of one-dimensional integral equations along the ballooning coordinate (quasi-neutrality and parallel Ampere's law). Furthermore, theoretical analyses of the eigenmode dispersion relation, which is given in a compact analytical form in the small ion orbit width limit (compared to the radial wavelength), provide a basis for explaining the general properties of the modes. It is emphasized that instability requires both sufficiently strong thermal ion temperature gradients and that the plasma be not too far away from ideal MHD marginal stability. (C) 1999 American Institute of Physics. [S1070-664X(99)93705-9]. C1 EURATOM Assoc, ENEA Fus, I-00044 Frascati, Italy. Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 USA. SW Inst Phys, Chengdu, Peoples R China. USN, Res Lab, Washington, DC 20375 USA. RP Zonca, F (reprint author), EURATOM Assoc, ENEA Fus, CP 65, I-00044 Frascati, Italy. RI chen, liu/I-2297-2013; Zonca, Fulvio/I-8236-2016 OI Zonca, Fulvio/0000-0002-9270-4704 NR 19 TC 79 Z9 79 U1 0 U2 13 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1917 EP 1924 DI 10.1063/1.873449 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500030 ER PT J AU Sanford, TWL Mock, RC Spielman, RB Haines, MG Chittenden, JP Whitney, KG Apruzese, JP Peterson, DL Greenly, JB Sinars, DB Reisman, DB Mosher, D AF Sanford, TWL Mock, RC Spielman, RB Haines, MG Chittenden, JP Whitney, KG Apruzese, JP Peterson, DL Greenly, JB Sinars, DB Reisman, DB Mosher, D TI Wire array Z-pinch insights for enhanced x-ray production SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID POWER; SIMULATIONS; IMPLOSIONS; PLASMAS; SYMMETRY; CARBON; SATURN; FUSION; MODEL AB Comparisons of measured total radiated x-ray power from annular wire-array z-pinches with a variety of models as a function of wire number, array mass, and load radius are reviewed. The data, which are comprehensive, have provided important insights into the features of wire-array dynamics that are critical for high x-ray power generation. Collectively, the comparisons of the data with the model calculations suggest that a number of underlying dynamical mechanisms involving cylindrical asymmetries and plasma instabilities contribute to the measured characteristics. For example, under the general assumption that the measured risetime of the total-radiated-power pulse is related to the thickness of the plasma shell formed on axis, the Heuristic Model [IEEE Trans. Plasma Sci. 26, 1275 (1998)] agrees with the measured risetime under a number of specific assumptions about the way the breakdown of the wires, the wire-plasma expansion, and the Rayleigh-Taylor instability in the r-z plane, develop. Likewise, in the high wire-number regime (where the wires are calculated to form a plasma shell prior to significant radial motion of the shell) the comparisons show that the variation in the power of the radiation generated as a function of load mass and array radius can be simulated by the two-dimensional Eulerian-radiation-magnetohydrodynamics code (E-RMHC) [Phys. Plasmas 3, 368 (1996)], using a single random-density perturbation that seeds the Rayleigh-Taylor instability in the r-z plane. For a given pulse-power generator, the comparisons suggest that (1) the smallest interwire gaps compatible with practical load construction and (2) the minimum implosion time consistent with the optimum required energy coupling of the generator to the load should produce the highest total-radiated-power levels. (C) 1999 American Institute of Physics. [S1070-664X(99)91505-7]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BZ, England. USN, Res Lab, Radiat Hydrodynam Branch, Washington, DC 20375 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Cornell Univ, Plasma Studies Lab, Ithaca, NY 14853 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. USN, Res Lab, Pulsed Power Phys Branch, Washington, DC 20375 USA. RP Sanford, TWL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 42 TC 27 Z9 27 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2030 EP 2040 DI 10.1063/1.873458 PN 2 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500044 ER PT J AU Deeney, C Coverdale, CA Douglas, MR Nash, TJ Spielman, RB Struve, KW Whitney, KG Thornhill, JW Apruzese, JP Clark, RW Davis, J Beg, FN Ruiz-Camacho, J AF Deeney, C Coverdale, CA Douglas, MR Nash, TJ Spielman, RB Struve, KW Whitney, KG Thornhill, JW Apruzese, JP Clark, RW Davis, J Beg, FN Ruiz-Camacho, J TI Titanium K-shell x-ray production from high velocity wire array implosions on the 20-MA Z accelerator SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID Z-PINCH IMPLOSIONS; ALUMINUM; EMISSION; PLASMAS; POWER; OPTIMIZATION; INSTABILITY; SYMMETRY; YIELDS; ARGON AB The advent of the 20-MA Z accelerator [R. B. Spielman, C. Deeney, G. A. Chandler et al., Phys. Plasmas 5, 2105 (1997)] has enabled implosions of large diameter, high-wire-number arrays of titanium to begin testing Z pinch K-shell scaling theories. The 2 cm long titanium arrays, which were mounted on a 40 mm diameter, produced between 75+/-15 to 125+/-20 kJ of K-shell x rays. A mass scan indicates that, as predicted, higher velocity implosions in the series produced higher x-ray yields. Spectroscopic analyses indicate that these high velocity implosions achieved peak electron temperatures from 2.7+/-0.1 to 3.2+/-0.2 keV and obtained a K-shell emission mass participation of up to 12%. (C) 1999 American Institute of Physics. [S1070-664X(99)97105-7]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Univ London Imperial Coll Sci Technol & Med, Plasma Phys Grp, London, England. RP Deeney, C (reprint author), Sandia Natl Labs, MS-1194,POB 5800, Albuquerque, NM 87185 USA. NR 29 TC 62 Z9 63 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2081 EP 2088 DI 10.1063/1.873461 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500050 ER PT J AU Sethian, JD Bodner, SE Colombant, DG Dahlburg, JP Obenschain, SP Pawley, CJ Serlin, V Gardner, JH Aglitskiy, Y Chan, Y Deniz, AV Lehecka, T Klapisch, M AF Sethian, JD Bodner, SE Colombant, DG Dahlburg, JP Obenschain, SP Pawley, CJ Serlin, V Gardner, JH Aglitskiy, Y Chan, Y Deniz, AV Lehecka, T Klapisch, M TI Direct drive acceleration of planar liquid deuterium targets SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LA SP Amer Phys Soc, Div Plasma Phys ID RAYLEIGH-TAYLOR INSTABILITY; LOCAL-THERMODYNAMIC-EQUILIBRIUM; LASER-CREATED PLASMAS; IONIZATION MODEL; FUSION AB The Nike laser (similar to 2-3 kJ, similar to 10(14) W/cm(2)) has been used to ablatively accelerate planar liquid deuterium targets. These experiments are designed to test some aspects of a high gain direct drive target design. The target consists of a low-density foam that is filled with liquid deuterium and covered with a thin polyimide membrane. The measured target trajectory agrees well with one-dimensional (1D) simulations. The growth of the areal mass modulations were measured with a new, 1.26 keV x-ray backlighter. The modulations appear later and grow to a smaller amplitude when the foot of the laser pulse is made spatially smoother. A thin layer of gold on the front of the target reduces the modulations. The results are compared with 2D modeling. [S1070-664X(99)96205-5]. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. Sci Applicat Int Corp, McLean, VA 22310 USA. ARTEP Inc, Columbia, MD 21045 USA. RP USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. EM sethian@this.nrl.navy.mil NR 20 TC 15 Z9 15 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 1070-664X EI 1089-7674 J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2089 EP 2094 DI 10.1063/1.873498 PN 2 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500051 ER PT J AU Levush, B Blank, M Calame, J Danly, B Nguyen, K Pershing, D Cooke, S Latham, P Petillo, J Antonsen, T AF Levush, B Blank, M Calame, J Danly, B Nguyen, K Pershing, D Cooke, S Latham, P Petillo, J Antonsen, T TI Modeling and design of millimeter wave gyroklystrons SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID HIGH-POWER; GAIN AB A series of high power, high efficiency K-a-band and W-band gyroklystron experiments has been conducted recently at the Naval Research Laboratory (NRL). Stagger tuning of the cavities for bandwidth enhancement is commonly used in the conventional multicavity klystrons. The desired stagger tuning is usually achieved via mechanical tuning of the individual cavities. However, in the millimeter wave regime, particularly, in the case of the high average power operation, it is desirable to be able to achieve the required stagger tuning by design. The NRL gyroklystron experiments explored the tradeoffs between power, bandwidth, efficiency, and gain to study the effects of large stagger tuning in millimeter wave without resorting to mechanical tuning of the cavities. Both, K-a-band and W-band, experiments demonstrated a record power-bandwidth product. The success of the experiments was due in large part to a battery of improved large-signal, stability, and cold test codes employed in the modeling and design stage. Theoretical models that provide the basis for these design simulation tools and the design methodology will be presented. (C) 1999 American Institute of Physics. [S1070-664X(99)92905-1]. C1 USN, Res Lab, Washington, DC 20375 USA. KN Res, Silver Spring, MD 20906 USA. Mission Res Corp, Newington, VA 22102 USA. Sci Applicat Int Corp, Mclean, VA 22102 USA. Omega P Inc, New Haven, CT 06520 USA. Univ Maryland, College Pk, MD 20742 USA. RP Levush, B (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Cooke, Simon/A-9530-2010 NR 18 TC 13 Z9 14 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2233 EP 2240 DI 10.1063/1.873476 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500069 ER PT J AU Jensen, KL AF Jensen, KL TI Field emitter arrays for plasma and microwave source applications SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID INDUCTIVE OUTPUT AMPLIFIERS; CHILD-LANGMUIR LAW; VACUUM MICROELECTRONICS; ELECTRON-EMISSION; DEFLECTION MICROWAVE; PLANAR LENSES; DEVICES; SILICON; OPTIMIZATION; SIMULATION AB Field emitter arrays (FEAs) stand to strongly impact device performance when physical size, weight, power consumption, beam current, and/or high pulse repetition frequencies are an issue. FEAs are capable of instant ON/OFF performance, high brightness, high current density, large transconductance to capacitance ratio, and low voltage operation characteristics. Advanced microwave power tubes, and in particular, inductive output amplifiers, are by far the most technically challenging use to date. Other important uses include, e.g., electron sources for micropropulsion systems-Hall thrusters-and tethers for satellites, and (the most widely pursued application) field emission displays. The characteristics of field emitters that make them attractive to such applications shall be surveyed. A thorough analytical model of a field emitter array, beginning with a review of the nature of field emission and continuing with an analytical model of a single emitter and the operation of an array of emitters, shall be presented. In particular, attention shall be directed towards those features of FEAs that render them attractive as cold cathode candidates for electron beam generation. Tip characteristics, such as emission distribution, and array operation, such as space charge effects, will be analyzed in the context of the model. Finally, restricting attention to microwave applications, the performance of a tapered-helix inductive output amplifier to highlight the advantages of high frequency emission gating of the electron beam in a power tube shall be investigated. [S1070- 664X(99)93905-8]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Jensen, KL (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Jensen, Kevin/I-1269-2015 OI Jensen, Kevin/0000-0001-8644-1680 NR 77 TC 77 Z9 77 U1 1 U2 14 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2241 EP 2253 DI 10.1063/1.873502 PN 2 PG 13 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500070 ER PT J AU Haber, I Friedman, A Grote, DP Lund, SM Kishek, RA AF Haber, I Friedman, A Grote, DP Lund, SM Kishek, RA TI Recent progress in the simulation of heavy ion beams SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID PARTICLE BEAMS; TRANSPORT; EMITTANCE; ENERGY; LBNL AB Production of electric power by using a beam of heavy ions to ignite an inertially-confined fusion target requires the focusing of high-power beams onto a small spot several meters distant from the final lens system. Beams with the necessary intensity generally behave like warm nonneutral bounded plasmas where beam kinetic temperatures are sufficiently high that a cold-plasma description can be inadequate for describing the collective space-charge modes. In view of the complexity of the self-consistent nonlinear dynamics, analytic study has largely been limited to the singular Kapchinskij-Vladimirskij (K-V) distribution. Numerical simulations, primarily using the WARP [D. P. Grote, A. Friedman, I. Haber, W. Fawley, and J. L. Vay, Nucl. Instrum. Methods Phys. Res. A 415, 428 (1998)] particle-in-cell (PIC)/accelerator code, have been employed to identify the degree to which the analytic results, especially the predictions of unstable modes, are applicable to realistic beam distributions. During extensive benchmarking of the code against experiments at Lawrence Berkeley National Laboratory, Lawrence Livermore National Laboratory, and the University of Maryland, a particular feature of the beam which has been seen in both experiment and simulation is the launching, in the source region, of collective warm-plasma oscillations similar to those predicted on the basis of the K-V analysis. (C) 1999 American Institute of Physics. [S1070-664X(99)96605-3]. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. RP Haber, I (reprint author), USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. NR 33 TC 24 Z9 23 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2254 EP 2261 DI 10.1063/1.873477 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500071 ER PT J AU Granatstein, VL Parker, RK Armstrong, CM AF Granatstein, VL Parker, RK Armstrong, CM TI Vacuum electronics at the dawn of the twenty-first century SO PROCEEDINGS OF THE IEEE LA English DT Article DE cathodes; free-electron laser; gyrotron; high-power microwaves; klystron; magnet materials; microwave power; module; numerical simulation; RF window materials; traveling-wave tube (TWT; vacuum electronics ID GYROKLYSTRON AMPLIFIER; STIMULATED EMISSION; MAGNETIC-FIELD; 1ST OPERATION; MICROWAVE; PERFORMANCE; DESIGN; LASER; BEAM AB In this introduction to the Special Issue on vacuum electronics, the history, operating principles, and recent technological trends of vacuum electronic devices are reviewed. The development of microwave power tubes is described; and improvements in these devices over the past quarter of a century are highlighted. These improvements have been substantial and have been driven by modern high-power applications and by advances in materials and computational science. The second part of this paper describes the advent of a new class of vacuum electronics generator as involving relativistic electron beams and interaction with fast waves (e.g., gyrotrons,, free-electron lasers). These new types of generators are opening the electromagnetic spectrum beyond the microwave region (i.e., millimeter-wave, infrared, ultraviolet, and even X ray) for applications of high-power, coherent generators of electromagnetic radiation. C1 Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. Univ Maryland, Dept Elect Engn, College Pk, MD 20742 USA. USN, Res Lab, Vacuum Elect Branch, Washington, DC 20375 USA. Northrop Grumman Corp, Rolling Meadows, IL 60008 USA. RP Granatstein, VL (reprint author), Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. NR 87 TC 60 Z9 64 U1 5 U2 22 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9219 J9 P IEEE JI Proc. IEEE PD MAY PY 1999 VL 87 IS 5 BP 702 EP 716 DI 10.1109/5.757251 PG 15 WC Engineering, Electrical & Electronic SC Engineering GA 189XP UT WOS:000079931700002 ER PT J AU Felch, KL Danly, BG Jory, HR Kreischer, KE Lawson, W Levush, B Temkin, RJ AF Felch, KL Danly, BG Jory, HR Kreischer, KE Lawson, W Levush, B Temkin, RJ TI Characteristics and applications of fast-wave gyrodevices SO PROCEEDINGS OF THE IEEE LA English DT Review DE accelerator RF systems; cyclotron resonance; electron tubes; gyrotrons; microwave tubes; millimeter-wave amplifiers; millimeter-wave oscillators; millimeter-wave radar; millimeter-wave tubes; plasma heating; superconducting magnets ID GYRO-TWT AMPLIFIER; HIGH-POWER; GYROKLYSTRON-AMPLIFIER; WIDE-BAND; TUBE AMPLIFIER; ABSOLUTE INSTABILITY; CYCLOTRON HARMONICS; MEGAWATT GYROTRON; LINEAR COLLIDERS; MODE COMPETITION AB Gyrodevice oscillators and amplifiers (or gyro-oscillators and gyro-amplifiers) are being utilized in a variety of applications where high power levels are required at millimeter-wave frequencies. Gyro-oscillators, developed primarily for magnetic fusion research applications, have achieved power levels near I MW for poise durations in excess of 1 s at frequencies above 100 GHz. Continued work on these devices should enable them to achieve continuous-wave operation at multimegawatt power levels at frequencies in the 100-GHz to 200-GHz range, thereby meeting the requirements of planned magnetic fusion experiments. The development of gyro-oscillators for:fusion experiments has led to the utilization of the devices in several industrial applications, such as ceramic sintering and metal joining.:Activities in this area involve adapting the oscillators to the industrial environment where reliability,efficiency, and ease of operation ar-e paramount. Gyro-amplifiers are being developed for applications requiring phase coherence and instantaneous bandwidth, such as in linear accelerators and millimeter-wave radar. Impressive results from X-band to W-band already suggest the promise of these devices. Potential new applications and novel gyrodevice design approaches continue to attract the attention of researchers around the world. C1 Commun & Power Ind, Palo Alto, CA 94304 USA. USN, Res Lab, Washington, DC 20375 USA. MIT, Ctr Plasma Fus, Cambridge, MA 02139 USA. Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. RP Commun & Power Ind, Palo Alto, CA 94304 USA. NR 188 TC 155 Z9 164 U1 2 U2 20 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9219 EI 1558-2256 J9 P IEEE JI Proc. IEEE PD MAY PY 1999 VL 87 IS 5 BP 752 EP 781 DI 10.1109/5.757254 PG 30 WC Engineering, Electrical & Electronic SC Engineering GA 189XP UT WOS:000079931700005 ER PT J AU Antonsen, TM Mondelli, AA Levush, B Verboncoeur, JP Birdsall, CK AF Antonsen, TM Mondelli, AA Levush, B Verboncoeur, JP Birdsall, CK TI Advances in modeling and simulation of vacuum electronic devices SO PROCEEDINGS OF THE IEEE LA English DT Article DE computational electrodynamics; microwave amplifiers; microwave sources; numerical simulation; particle in cell; vacuum electronic devices ID BAND GYROKLYSTRON AMPLIFIER; POWER GYROTRON OSCILLATORS; PARTICLE SIMULATION; SECONDARY-EMISSION; CIRCUIT SOLUTION; GAUSS LAW; DESIGN; CODES; PLASMA; COMPETITION AB Recent advances in the modeling and simulation of vacuum electronic devices are reviewed. Design of these devices makes use of a variety of physical models and numerical code types. Progress in the development of these models and codes is outlined and illustrated With specific examples. The state of the art in device simulation is evolving to the point such that devices can be designed on the computer, thereby eliminating many trial and error fabrication and test steps. The role of numerical simulation in the design process can be expected to grow further in the future. C1 Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. Sci Applicat Int Corp, Appl Phys Operat, Mclean, VA 22102 USA. USN, Res Lab, Vacuum Elect Branch, Washington, DC 20375 USA. Univ Calif Berkeley, Dept Elect Engn & Comp Sci, Berkeley, CA 94720 USA. RP Antonsen, TM (reprint author), Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. RI Antonsen, Thomas/D-8791-2017 OI Antonsen, Thomas/0000-0002-2362-2430 NR 90 TC 46 Z9 49 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9219 J9 P IEEE JI Proc. IEEE PD MAY PY 1999 VL 87 IS 5 BP 804 EP 839 DI 10.1109/5.757256 PG 36 WC Engineering, Electrical & Electronic SC Engineering GA 189XP UT WOS:000079931700007 ER PT J AU Calame, JP Abe, DK AF Calame, JP Abe, DK TI Applications of advanced materials technologies to vacuum electronic devices SO PROCEEDINGS OF THE IEEE LA English DT Article DE dielectric materials; electron tubes; materials science and technology; microwave technology ID MULTISTAGE DEPRESSED COLLECTORS; PERMANENT-MAGNETS; FIELD SOURCES; HEAT-FLUX; GYROKLYSTRON; TUBES; AMPLIFICATION; ACCELERATORS; GYROTRON; DIAMOND AB The applications of advanced engineering materials in modern vacuum electronic devices are reviewed. Unique materials with desirable thermal, mechanical, electrical, and magnetic properties are playing a crucial role in raising the average power capability, bandwidth, and efficiency of microwave and millimeter wave amplifiers and oscillators. Five major materials-related topics and technologies are covered in this article. diamond electromagnetic windows,and electrode supports; electromagnetically lossy composite ceramics fdr control of instabilities; methods of cooling metal structures; pyrolytic graphite beam collectors and electron-gun modulation grids;: and rare-earth permanent magnets fbr confining electron beams: For each topic, this article reviews the background physics, describes the importance of the technology: to :vacuum electronics, presents illustrative examples of how such technologies perform, and reviews current results from the literature. C1 USN, Res Lab, Washington, DC 20375 USA. RP USN, Res Lab, Code 6843, Washington, DC 20375 USA. EM calame@mmace.nrl.navy.mil; abe@mmace.nrl.navy.mil RI Abe, David/D-7546-2013 NR 85 TC 23 Z9 24 U1 0 U2 10 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9219 EI 1558-2256 J9 P IEEE JI Proc. IEEE PD MAY PY 1999 VL 87 IS 5 BP 840 EP 864 DI 10.1109/5.757257 PG 25 WC Engineering, Electrical & Electronic SC Engineering GA 189XP UT WOS:000079931700008 ER PT J AU Muth, ER Koch, KL Stern, RM Thayer, JF AF Muth, ER Koch, KL Stern, RM Thayer, JF TI Effect of autonomic nervous system manipulations on gastric myoelectrical activity and emotional responses in healthy human subjects SO PSYCHOSOMATIC MEDICINE LA English DT Article DE stress; autonomic nervous system; gastric myoelectrical activity; emotional responses; gastrointestinal system; electrogastrogram ID RESPIRATORY SINUS ARRHYTHMIA; INDUCED MOTION SICKNESS; HEART-RATE; FUNCTIONAL DYSPEPSIA; COLD STRESS; PERTURBATION; MOTILITY; TONE AB Objective: The aim of this study was to determine the gastric myoelectrical and emotional responses provoked by two psychophysiological stimuli known to cause in one case increased sympathetic nervous system activity and in the other increased parasympathetic nervous system activity. Methods: Electrogastrograms (EGGs) were recorded, and interbeat intervals (IBIs) were obtained from electrocardiographic recordings from 20 subjects during baseline and in response to a shock avoidance task (shock stimulus) and forehead cooling (dive stimulus). After each experimental period, subjects reported their emotional experience by rating descriptors ranging from serenity to excitement. Results: During the shock stimulus, IBIs decreased significantly (p < .05), gastric tachyarrhythmias increased (p < .05), and emotional arousal increased, as indexed by reports of increased interest, excitement, and activation. In contrast, during the dive stimulus, IBIs increased (p < .05), but there were no associated changes in gastric myoelectrical activity or emotional arousal. Conclusions: Acute stress can evoke arousal and dysrhythmic gastric myoelectrical activity, and these acute changes, which occur in healthy individuals, may provide insight into functional gastrointestinal disorders. C1 USN, Aerosp Med Res Lab, Pensacola, FL 32508 USA. Penn State Univ, Dept Med, University Pk, PA 16802 USA. Penn State Univ, Dept Psychol, University Pk, PA 16802 USA. Univ Missouri, Dept Psychol, Columbia, MO 65211 USA. RP Muth, ER (reprint author), USN, Aerosp Med Res Lab, 51 Hovey Rd, Pensacola, FL 32508 USA. NR 32 TC 35 Z9 36 U1 1 U2 5 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0033-3174 J9 PSYCHOSOM MED JI Psychosom. Med. PD MAY-JUN PY 1999 VL 61 IS 3 BP 297 EP 303 PG 7 WC Psychiatry; Psychology; Psychology, Multidisciplinary SC Psychiatry; Psychology GA 199HF UT WOS:000080474600008 PM 10367609 ER PT J AU Turner, NH ten Brummelaar, TA Mason, BD AF Turner, NH ten Brummelaar, TA Mason, BD TI Adaptive optics observations of Arcturus using the Mount Wilson 100 inch telescope SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article ID SYSTEM AB Upon inspection of the multiple-star results in the Hipparcos catalog, the flag for entry number 69673 particularly stands out; it is Arcturus, for which no companion has been reported previously. The Hipparcos companion is reported to be at a separation of 0." 255 + 0." 039 with a magnitude difference in a broadband filter (peaked near 460 nm) of 3.33 +/- 0.31. We present recent results using the natural guide star adaptive optics system on the Mount Wilson 100 inch telescope showing Arcturus to be a single star. C1 Mt Wilson Inst, Mt Wilson, CA 91023 USA. Georgia State Univ, Ctr High Angular Resolut Astron, Atlanta, GA 30303 USA. USN Observ, Washington, DC 20390 USA. RP Turner, NH (reprint author), Mt Wilson Inst, Mt Wilson, CA 91023 USA. NR 8 TC 12 Z9 12 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0004-6280 J9 PUBL ASTRON SOC PAC JI Publ. Astron. Soc. Pac. PD MAY PY 1999 VL 111 IS 759 BP 556 EP 558 DI 10.1086/316353 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 197JQ UT WOS:000080362000003 ER PT J AU Wolfe, VF DiPippo, LC Ginis, R Squadrito, M Wohlever, S Zykh, I Johnston, R AF Wolfe, VF DiPippo, LC Ginis, R Squadrito, M Wohlever, S Zykh, I Johnston, R TI Expressing and enforcing timing constraints in a dynamic real-time CORBA system SO REAL-TIME SYSTEMS LA English DT Article DE real-time; CORBA; distributed; dynamic; timing constraints AB Distributed real-time applications have presented the need to extend the Object Management Group's Common Object Request Broker Architecture (CORBA) standard to support real-time. This paper describes a Dynamic Real-Time CORBA system, which supports the expression and enforcement of end-to-end timing constraints as an extension to a commercial CORBA system. The paper also describes performance tests that demonstrate the system's ability to enforce expressed timing constraints. C1 Univ Rhode Isl, Dept Comp Sci, Kingston, RI 02881 USA. USN, SPAWAR Syst Ctr, San Diego, CA 92152 USA. RP Wolfe, VF (reprint author), Univ Rhode Isl, Dept Comp Sci, Kingston, RI 02881 USA. NR 18 TC 5 Z9 6 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0922-6443 J9 REAL-TIME SYST JI Real-Time Syst. PD MAY PY 1999 VL 16 IS 2-3 BP 253 EP 280 DI 10.1023/A:1008055224220 PG 28 WC Computer Science, Theory & Methods SC Computer Science GA 211YF UT WOS:000081188900005 ER PT J AU Asif, SAS Wahl, KJ Colton, RJ AF Asif, SAS Wahl, KJ Colton, RJ TI Nanoindentation and contact stiffness measurement using force modulation with a capacitive load-displacement transducer SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID MICROSCOPE; HARDNESS; CREEP AB We have implemented a force modulation technique for nanoindentation using a three-plate capacitive load-displacement transducer. The stiffness sensitivity of the instrument is similar to 0.1 N/m. We show that the sensitivity of this instrument is sufficient to detect long-range surface forces and to locate the surface of a specimen. The low spring mass (236 mg), spring constant (116 N/m), and damping coefficient (0.008 Ns/m) of the transducer allows measurement of the damping losses for nanoscale contacts. We present the experimental technique, important specimen mounting information, and system calibration for nanomechanical property measurement. (C) 1999 American Institute of Physics. [S0034-6748(99)04105-2]. C1 Univ Florida, Gainesville, FL 32611 USA. USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Asif, SAS (reprint author), Univ Florida, Gainesville, FL 32611 USA. OI Wahl, Kathryn/0000-0001-8163-6964 NR 15 TC 169 Z9 170 U1 2 U2 35 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAY PY 1999 VL 70 IS 5 BP 2408 EP 2413 DI 10.1063/1.1149769 PG 6 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 193AU UT WOS:000080113600033 ER PT J AU Curtin, TB Benson, RA AF Curtin, TB Benson, RA TI ONR program in underwater acoustic communications SO SEA TECHNOLOGY LA English DT Article C1 Off Naval Res, Ocean Space & Atmosphere Dept, Arlington, VA 22217 USA. RP Curtin, TB (reprint author), Off Naval Res, Ocean Space & Atmosphere Dept, Arlington, VA 22217 USA. NR 0 TC 5 Z9 9 U1 0 U2 0 PU COMPASS PUBL INC PI ARLINGTON PA SUITE 1000 1117 N 19 ST, ARLINGTON, VA 22209 USA SN 0093-3651 J9 SEA TECHNOL JI Sea Technol. PD MAY PY 1999 VL 40 IS 5 BP 17 EP + PG 8 WC Engineering, Ocean SC Engineering GA 199LV UT WOS:000080484300003 ER PT J AU Blackmon, F Jarvis, S Morrissey, R Lambert, D AF Blackmon, F Jarvis, S Morrissey, R Lambert, D TI High-rate underwater acoustic telemetry with Naval applications SO SEA TECHNOLOGY LA English DT Article C1 USN, Undersea Warfare Ctr, Newport, RI 02840 USA. RP Blackmon, F (reprint author), USN, Undersea Warfare Ctr, Newport, RI 02840 USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU COMPASS PUBL INC PI ARLINGTON PA SUITE 1000 1117 N 19 ST, ARLINGTON, VA 22209 USA SN 0093-3651 J9 SEA TECHNOL JI Sea Technol. PD MAY PY 1999 VL 40 IS 5 BP 67 EP 70 PG 4 WC Engineering, Ocean SC Engineering GA 199LV UT WOS:000080484300008 ER PT J AU Errico, RM Langland, R AF Errico, RM Langland, R TI Notes on the appropriateness of "bred modes" for generating initial perturbations used in ensemble prediction SO TELLUS SERIES A-DYNAMIC METEOROLOGY AND OCEANOGRAPHY LA English DT Letter ID SINGULAR VECTORS; PREDICTABILITY EXPERIMENTS; CHAOTIC SYSTEMS; ERROR GROWTH; FORECASTS; RESOLUTION; ASSIMILATION; UNCERTAINTY; LYAPUNOV; EQUATION AB Papers by Szunyogh and co-workers and Iyengar and co-workers, among others, claim that "bred growing vectors" (BGVs) are appropriate for generating initial perturbations for application to ensemble weather prediction. The theoretical bases for this claim are purported relationships between the bred vectors and what are called local Lyapunov vectors (LLVs). Several statements in these papers are inaccurate, however, regarding: the properties of LLVs in contrast to those of singular vectors; the relationship between LLVs and BGVs; the relationship between BGVs and analysis errors; the relationship between singular vectors and dynamic imbalances; and the adequacy of very low-resolution models to characterize singular vectors of models used for numerical weather prediction. These inaccuracies and their implications for the use of BGVs in ensemble weather prediction are discussed here. C1 Natl Ctr Atmospher Res, Boulder, CO 80307 USA. USN, Res Lab, Monterey, CA USA. RP Errico, RM (reprint author), Natl Ctr Atmospher Res, POB 3000, Boulder, CO 80307 USA. NR 53 TC 11 Z9 11 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0280-6495 J9 TELLUS A JI Tellus Ser. A-Dyn. Meteorol. Oceanol. PD MAY PY 1999 VL 51 IS 3 BP 431 EP 441 PG 11 WC Meteorology & Atmospheric Sciences; Oceanography SC Meteorology & Atmospheric Sciences; Oceanography GA 208ZF UT WOS:000081021900007 ER PT J AU Errico, RM Langland, R AF Errico, RM Langland, R TI Reply to: Comments on "Notes on the appropriateness of 'bred modes' for generating initial perturbations" SO TELLUS SERIES A-DYNAMIC METEOROLOGY AND OCEANOGRAPHY LA English DT Letter C1 Natl Ctr Atmospher Res, Boulder, CO 80307 USA. USN, Res Lab, Monterey, CA USA. RP Errico, RM (reprint author), Natl Ctr Atmospher Res, Box 3000, Boulder, CO 80307 USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0280-6495 J9 TELLUS A JI Tellus Ser. A-Dyn. Meteorol. Oceanol. PD MAY PY 1999 VL 51 IS 3 BP 450 EP 451 DI 10.1034/j.1600-0870.1999.t01-3-00009.x PG 2 WC Meteorology & Atmospheric Sciences; Oceanography SC Meteorology & Atmospheric Sciences; Oceanography GA 208ZF UT WOS:000081021900009 ER PT J AU Corwin, AL Tien, NTK Bounlu, K Winarno, J Putri, MP Laras, K Larasati, RP Sukri, N Endy, T Sulaiman, HA Hyams, KC AF Corwin, AL Tien, NTK Bounlu, K Winarno, J Putri, MP Laras, K Larasati, RP Sukri, N Endy, T Sulaiman, HA Hyams, KC TI The unique riverine ecology of hepatitis E virus transmission in South-East Asia SO TRANSACTIONS OF THE ROYAL SOCIETY OF TROPICAL MEDICINE AND HYGIENE LA English DT Article DE hepatitis E virus; hepatitis E virus antibodies; prevalence; ecology; epidemiology; South-East Asia; Indonesia; Viet Nam; Laos ID NON-B-HEPATITIS; WEST KALIMANTAN BORNEO; EPIDEMIC NON-A; MOLECULAR-BIOLOGY; VIRAL-HEPATITIS; PREVALENCE; INDONESIA AB The ecology of hepatitis E virus (HEV) transmission in South-East Asia was assessed from a review of 6 published and 3 unpublished NAMRU-2 reports of hepatitis outbreak investigations, cross-sectional prevalence studies, and hospital-based case-control studies. Findings from Indonesia and Viet Nam show epidemic foci centred in jungle, riverine environments. In contrast, few cases of acute, clinical hepatitis from cities in Indonesia, Viet Nam and Laos could be attributed to HEV. When communities in Indonesia were grouped into areas of low (<40%), medium (40-60%), and high (>60%) prevalence of anti-HEV antibodies, uses of river water for drinking and cooking, personal washing, and human excreta disposal were all significantly associated with high prevalence of infection. Conversely, boiling of river drinking water was negatively associated with higher prevalence (P < 0.01). The protective value of boiling river water was also shown in sporadic HEV transmission in Indonesia and in epidemic and sporadic spread in Viet Nam. Evidence from Indonesia indicated that the decreased dilution of HEV in river water due to unusually dry weather contributed to risk of epidemic HEV transmission. But river flooding conditions and contamination added to the risk of HEV infection in Viet Nam. These findings attest to a unique combination of ecological and environmental conditions predisposing to epidemic HEV spread in South-East Asia. C1 USN, Med Res Unit 2, Jakarta, Indonesia. Inst Pasteur, Ho Chi Minh City, Vietnam. Prov Hlth Serv, Sintang Dist, W Kalimantan, Indonesia. Armed Forces Res Inst Med Sci, Bangkok 10400, Thailand. Univ Indonesia, Fac Med, Jakarta, Indonesia. USN, Med Res Inst, Bethesda, MD USA. RP Corwin, AL (reprint author), US NAMRU 2, Box 3,Unit 8132, APO, AP 96520 USA. EM corwin@smtp.namru2.go.id NR 30 TC 38 Z9 40 U1 0 U2 2 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0035-9203 EI 1878-3503 J9 T ROY SOC TROP MED H JI Trans. Roy. Soc. Trop. Med. Hyg. PD MAY-JUN PY 1999 VL 93 IS 3 BP 255 EP 260 DI 10.1016/S0035-9203(99)90014-7 PG 6 WC Public, Environmental & Occupational Health; Tropical Medicine SC Public, Environmental & Occupational Health; Tropical Medicine GA 216TT UT WOS:000081460500010 PM 10492753 ER PT J AU Knechtle, SJ Kirk, AD Fechner, JH Hong, X Dong, Y Hamawy, MM Harlan, DM AF Knechtle, SJ Kirk, AD Fechner, JH Hong, X Dong, Y Hamawy, MM Harlan, DM TI Inducing unresponsiveness by the use of anti-CD3 immunotoxin, CTLA4-Ig, and anti-CD40 ligand SO TRANSPLANTATION PROCEEDINGS LA English DT Article; Proceedings Paper CT International Symposium on Strategies for Improving Long-Term Transplant Outcome CY JAN 13-15, 1998 CL SAN JUAN, PUERTO RICO ID PRIMATE RENAL-ALLOGRAFTS; LONG-TERM ACCEPTANCE; CARDIAC ALLOGRAFTS; DEPLETION; TOLERANCE C1 Univ Wisconsin, Sch Med, Dept Surg, Madison, WI USA. USN, Med Res Inst, Immune Cell Biol Program, Bethesda, MD USA. RP Knechtle, SJ (reprint author), Univ Wisconsin Hosp, Dept Surg, Clin Sci Ctr H4784, 600 Highland Ave, Madison, WI 53792 USA. RI Kirk, Allan/B-6905-2012; Fechner, John/C-5962-2016 OI Fechner, John/0000-0002-8220-7237 NR 13 TC 17 Z9 17 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0041-1345 J9 TRANSPLANT P JI Transplant. Proc. PD MAY PY 1999 VL 31 IS 3B SU S BP 27S EP 28S DI 10.1016/S0041-1345(99)00100-1 PG 2 WC Immunology; Surgery; Transplantation SC Immunology; Surgery; Transplantation GA 195YR UT WOS:000080281200009 PM 10330966 ER PT J AU Schaafsma, DT Mossadegh, R Sanghera, JS Aggarwal, ID Gilligan, JM Tolk, NH Luce, M Generosi, R Perfetti, P Cricenti, A Margaritondo, G AF Schaafsma, DT Mossadegh, R Sanghera, JS Aggarwal, ID Gilligan, JM Tolk, NH Luce, M Generosi, R Perfetti, P Cricenti, A Margaritondo, G TI Singlemode chalcogenide fiber infrared SNOM probes SO ULTRAMICROSCOPY LA English DT Article DE IR-SNOM; singlemode chalcogenide fiber; spatial resolution; FEL ID SCANNING OPTICAL MICROSCOPY; FABRICATION AB We have fabricated and tested infrared scanning near-field optical microscope (IR-SNOM) probe tips made from singlemode chalcogenide fiber. The process used to create the tips was similar to conventional micropipette-puller techniques, with some modifications to allow for the lower melting temperature and tensile strength of the chalcogenide fiber. SEM micrographs, showing tips with sub-micrometer physical dimensions, demonstrate the feasibility of this process. Topographical data obtained using a shear-force near-field microscope exhibits spatial resolution in the range 80-100 nm. Optical data in the infrared (near 3.5 mu m), using the probe tips in collection mode, indicates an optical spatial resolution approximately lambda/15. (C) 1999 Published by Elsevier Science B.V. hll rights reserved. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Ist Struttura Mat, Rome, Italy. Ecole Polytech Fed Lausanne, Inst Phys Appl, CH-1015 Lausanne, Switzerland. RP Schaafsma, DT (reprint author), USN, Res Lab, Div Opt Sci, Code 5606,4555 Overlook Ave SE, Washington, DC 20375 USA. RI Margaritondo, Giorgio/B-1367-2008; Gilligan, Jonathan/I-8938-2014 OI Gilligan, Jonathan/0000-0003-1375-6686 NR 17 TC 27 Z9 27 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3991 J9 ULTRAMICROSCOPY JI Ultramicroscopy PD MAY PY 1999 VL 77 IS 1-2 BP 77 EP 81 DI 10.1016/S0304-3991(99)00004-2 PG 5 WC Microscopy SC Microscopy GA 191HR UT WOS:000080017500007 ER PT J AU Wahl, KJ Dunn, DN Singer, IL AF Wahl, KJ Dunn, DN Singer, IL TI Wear behavior of Pb-Mo-S solid lubricating coatings SO WEAR LA English DT Article DE wear; molybdenum disulfide; solid lubrication; coatings ID BEAM-ASSISTED DEPOSITION; TRANSMISSION ELECTRON-MICROSCOPY; FILMS; BEARINGS; FRICTION; CONTACT AB Amorphous Pb-Mo-S coatings 200 to 510 nm thick were deposited by dual ion-beam deposition (IBD) onto steel and Si substrates, Coating wear studies were performed using ball-on-flat reciprocating sliding with steel ball counterfaces in dry air. Tests were run between 1 and 100,000 sliding cycles, and wear depths measured by interference microscopy. Morphology and chemistry of the as-deposited coatings and worn surfaces were investigated with optical microscopy, micro-Raman spectroscopy and cross-section high resolution transmission electron microscopy (HRTEM). Pb-Mo-S coatings were found to be quite wear resistant; no more than 25% of the coating thickness was removed by 10,000 sliding cycles. Two wear mechanisms were identified. At the nanometer scale, wear proceeded in a two-part process: transformation of the coating surface to MoS2, then layer-by-layer removal of MoS2. At the micrometer scale, wear occurred by plowing. The long endurance of Pb-Mo-S coatings was attributed to slow wear of the coatings, with lubricant redistribution processes playing a minor role. (C) 1999 Published by Elsevier Science S.A. C1 USN, Res Lab, Washington, DC 20375 USA. RP Wahl, KJ (reprint author), USN, Res Lab, Code 6176, Washington, DC 20375 USA. OI Wahl, Kathryn/0000-0001-8163-6964 NR 38 TC 63 Z9 64 U1 1 U2 12 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0043-1648 J9 WEAR JI Wear PD MAY PY 1999 VL 230 IS 2 BP 175 EP 183 DI 10.1016/S0043-1648(99)00100-3 PG 9 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 209VZ UT WOS:000081071300008 ER PT J AU Charles, PT Kusterbeck, AW AF Charles, PT Kusterbeck, AW TI Trace level detection of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) by microimmunosensor SO BIOSENSORS & BIOELECTRONICS LA English DT Article; Proceedings Paper CT 5th World Congress on Biosensors CY JUN 03-05, 1998 CL BERLIN, GERMANY DE RDX; explosives; immunosensor; antibody; antigen; fluorescence ID DISPLACEMENT FLOW IMMUNOSENSOR; LIQUID-CHROMATOGRAPHY; GROUNDWATER SAMPLES; 2,4,6-TRINITROTOLUENE; EXPLOSIVES; TNT; BIODEGRADATION; BIOSENSORS; MOLECULE; WATER AB Reported in this paper is the development and characterization of a highly sensitive microcapillary immunosensor for the detection of the explosive, hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). The immunosensor exploits antibodies as recognition elements for target antigens, fluorescence dye conjugates for reporter molecules and fused silica microcapillaries for its high surface-to-volume ratio. Detection of RDX with the microcapillary immunosensor requires covalent immobilization of anti-RDX antibodies on the inner core of the microcapillaries via heterobifunctional cross-linker chemistry. Subsequent saturation of all antibody binding domains follows with a synthetically prepared fluorescent analog of RDX. Displacement immunoassays were performed with the microcapillary immunosensor with the injection of unlabeled RDX at concentration levels from 1 part-per-trillion (pptr) to 1000 part-per-billion (ppb). As unlabeled RDX reaches the binding domain of the antibody, fluorescent RDX analog is displaced from the antibody, flows downstream and is measured by a spectrofluorometer. Fluorescence measurements of the displaced fluorescent RDX analog were equated to a standard calibration curve to quantify sample concentration. Complete evaluation of the RDX microcapillary immunosensor for selectivity and sensitivity was performed based on the following criteria: variable flow rates, antibody cross-reactivity, reproducibility and cross-linker (carbon spacer) comparison. Results indicate the lowest detectable limit (LDL) for RDX is 10 pptr (ng/l) with a linear dynamic range from 0.1 to 1000 ppb (mu g/l). (C) 1999 Elsevier Science S.A. All rights reserved. C1 USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. RP Kusterbeck, AW (reprint author), USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. NR 35 TC 31 Z9 31 U1 0 U2 9 PU ELSEVIER ADVANCED TECHNOLOGY PI OXFORD PA OXFORD FULFILLMENT CENTRE THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0956-5663 J9 BIOSENS BIOELECTRON JI Biosens. Bioelectron. PD APR 30 PY 1999 VL 14 IS 4 BP 387 EP 396 DI 10.1016/S0956-5663(99)00009-3 PG 10 WC Biophysics; Biotechnology & Applied Microbiology; Chemistry, Analytical; Electrochemistry; Nanoscience & Nanotechnology SC Biophysics; Biotechnology & Applied Microbiology; Chemistry; Electrochemistry; Science & Technology - Other Topics GA 208GE UT WOS:000080982000005 PM 10422240 ER PT J AU Clark, TR Carruthers, TF Matthews, PJ Duling, IN AF Clark, TR Carruthers, TF Matthews, PJ Duling, IN TI Phase noise measurements of ultrastable 10GHz harmonically modelocked fibre laser SO ELECTRONICS LETTERS LA English DT Article ID MODE-LOCKED LASERS; FIBER LASER AB Measurements are presented of the lowest timing jitter reported to date for a harmonically modelocked Er fibre laser. Phase detection noise measurements demonstrate a timing jitter of <10fs over a frequency range of 100Hz - 1MHz. C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA. RP Clark, TR (reprint author), USN, Res Lab, Div Opt Sci, Code 5650, Washington, DC 20375 USA. NR 5 TC 86 Z9 87 U1 0 U2 5 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 APR 29 PY 1999 VL 35 IS 9 BP 720 EP 721 DI 10.1049/el:19990516 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA 200MX UT WOS:000080545000028 ER PT J AU Dietrich, HB Kang, JU Frankel, MY AF Dietrich, HB Kang, JU Frankel, MY TI Implantation approach to SEU suppression in GaAs SO ELECTRONICS LETTERS LA English DT Article ID PHASE EPITAXY GAAS; TEMPERATURE; GROWTH AB It is shown that oxygen-implanted GaAs with oxygen concentrations of 10(20) cm(-3) (or 10(19) cm(-3) if co-implanted with Al), annealed in the 500-850 degrees C temperature range, can result in highly resistive layers with subpicosecond free-carrier lifetimes. It is suggested that such layers can be used to suppress single event upsets (SEUs) in GaAs digital circuits. C1 USN, Res Lab, Washington, DC 20375 USA. RP Dietrich, HB (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Kang, Jin/A-3228-2010 NR 4 TC 0 Z9 0 U1 0 U2 2 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 APR 29 PY 1999 VL 35 IS 9 BP 751 EP 752 DI 10.1049/el:19990512 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA 200MX UT WOS:000080545000049 ER PT J AU Steele, HM Lumpe, JD Turco, RP Bevilacqua, RM Massie, ST AF Steele, HM Lumpe, JD Turco, RP Bevilacqua, RM Massie, ST TI Retrieval of aerosol surface area and volume densities from extinction measurements: Application to POAM II and SAGE II SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ANTARCTIC STRATOSPHERIC AEROSOLS; PINATUBO AEROSOL; SULFURIC-ACID; POLAR-OZONE; INVERSION ALGORITHM; INFORMATION-CONTENT; SIZE DISTRIBUTIONS; OPTICAL-PROPERTIES; MOUNT-PINATUBO; EL-CHICHON AB In this paper we evaluate two different methods for determining aerosol surface area and volume densities from multiwavelength extinction measurements and apply them to the Polar Aerosol and Ozone Measurement (POAM II) and Stratospheric Aerosol and Gas Experiment (SAGE II) data. Systematic and random components of the retrieval error are calculated as a function of the size distribution parameters for a unimodal lognormal size distribution using principal component analysis and an empirical formulation based on the 1 mu m extinction measurement. The trade-off between these two components of the error is demonstrated for principal component analysis by varying the degree of constraint. We show how the systematic error can exceed the random error for lognormal size distributions typical of background aerosols. Retrieved surface areas for background aerosols can be underestimated by up to 50% through principal component analysis. Random errors depend on the estimated measurement error at each wavelength but, for the instruments considered, are expected to be 15-25%. Retrieved volume densities for background aerosols are underestimated by up to 30% through principal component analysis and suffer an additional random error component of 10-15%. The empirical formulation leads to altitude dependent systematic errors since the relative error depends on the particle number density. When different techniques are used to obtain aerosol surface area and volume, there is often a greater disagreement between different methods applied to the same data than the same method applied to data recorded by two different instruments. Systematic errors arising from the retrieval methodology should therefore be carefully considered in both validation and aerosol climatology studies. C1 Univ Calif Los Angeles, Dept Atmospher Sci, Los Angeles, CA 90095 USA. Computat Phys Inc, Fairfax, VA 22031 USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. USN, Res Lab, Washington, DC 20375 USA. RP Steele, HM (reprint author), Ctr Atmospher Sci, Dept Chem, Lensfield Rd, Cambridge CB2 1EW, England. EM helen.steele@atm.ch.cam.ac.uk NR 48 TC 23 Z9 23 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 27 PY 1999 VL 104 IS D8 BP 9325 EP 9336 DI 10.1029/1999JD900032 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 189UY UT WOS:000079925600015 ER PT J AU Swider, EE Rolison, DR AF Swider, EE Rolison, DR TI Catalytic desulfurization of carbon black on a platinum oxide electrode SO LANGMUIR LA English DT Article ID FUEL-CELL ELECTRODES; SULFUR; FUNCTIONALITY AB Organically bound sulfur is a common impurity in carbon blacks, such as vulcanized carbon and coal. Whereas this organosulfur is usually removed by heating to high temperatures, we describe a low-temperature method to desulfurize solid carbon via oxidation (ultimately to SO42-) On a Pt catalyst in oxygenated aqueous media. The reaction is monitored on Vulcan carbon, which is the favored support for the Pt catalysts used in fuel-cell electrodes but which has a high concentration (nominally 5000 ppm) of organosulfur. Vulcan carbon is electrodesulfurized by dispersing it in a heated, dilute HNO3 electrolyte where it can physically contact a Pt mesh anode that is maintained as Pt oxide. After 40-180 min of electrolysis in oxygenated solution at +1.0 V versus Pd/H, sulfate is present in the electrolyte (as measured by precipitation of BaSO4). X-ray photoelectron spectroscopy of the dried, electrodesulfurized carbon shows that similar to 30% of the near-surface organosulfur is removed. The remaining sulfur presumably does not react because it does not physically contact the hydrous platinum oxide (PtOxHy) at the electrode surface. Minimal desulfurization occurs at 0.2 V versus Pd/H, when the Pt mesh surface is composed of Pt-0. These electrochemical results show that oxidized Pt is the catalyst necessary for oxidative desulfurization. In deoxygenated solution, electrodesulfurization still occurs for electrolyses at +1.0 V versus Pd/H, but SO42- is not generated, indicating that SO2 is the partial oxidation product. The surface area and total oxygen content of the carbon are unaffected by the electrodesulfurization process. This simple, low-temperature method for desulfurization should be applicable to other forms of solid carbon containing organosulfur moieties. C1 USN, Res Lab, Surface Chem Branch, Washington, DC 20375 USA. RP Rolison, DR (reprint author), USN, Res Lab, Surface Chem Branch, Code 6170, Washington, DC 20375 USA. NR 26 TC 10 Z9 10 U1 4 U2 22 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD APR 27 PY 1999 VL 15 IS 9 BP 3302 EP 3306 PG 5 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 192YG UT WOS:000080106900043 ER PT J AU Subrahmanyam, MB AF Subrahmanyam, MB TI Roots of certain transcendental equations for elastic angular regions SO COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING LA English DT Article ID FREE-VIBRATION ANALYSIS; PLATES AB Certain important transcendental equations occur in the case of elastic angular regions while analyzing these regions for flexure, vibration, and buckling. Previously, these transcendental equations have been solved for roots and the data has been tabulated for different boundary conditions, as the angle of the region is varied. The purpose of this paper is to demonstrate that once we solve for the roots at a specific angular region, the roots for angular regions with angles ranging from 0 to 2 pi can be obtained via forward integration. (C) 1999 Elsevier Science S.A. All rights reserved. C1 USN, Air Warfare Ctr, Patuxent River, MD 20670 USA. RP Subrahmanyam, MB (reprint author), Lockheed Martin, Orlando, FL 32819 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0045-7825 J9 COMPUT METHOD APPL M JI Comput. Meth. Appl. Mech. Eng. PD APR 23 PY 1999 VL 173 IS 1-2 BP 217 EP 225 DI 10.1016/S0045-7825(98)00270-9 PG 9 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications; Mechanics SC Engineering; Mathematics; Mechanics GA 194TW UT WOS:000080210500014 ER PT J AU Nabel, GJ Woffendin, C King, SR Yang, ZY Ranga, U June, CH Xu, L Zaki, SR Sanchez, A AF Nabel, GJ Woffendin, C King, SR Yang, ZY Ranga, U June, CH Xu, L Zaki, SR Sanchez, A TI Gene therapy for AIDS and emerging viruses SO FASEB JOURNAL LA English DT Meeting Abstract C1 Univ Michigan, Med Ctr, Howard Hughes Med Inst, Ann Arbor, MI 48109 USA. USN, Med Res Ctr, Bethesda, MD 20084 USA. Ctr Dis Control, Atlanta, GA 30333 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 23 PY 1999 VL 13 IS 7 SU S BP A1591 EP A1591 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 226QX UT WOS:000082033401542 ER PT J AU Morris, CA Anderson, ML Stroud, RM Merzbacher, CI Rolison, DR AF Morris, CA Anderson, ML Stroud, RM Merzbacher, CI Rolison, DR TI Silica sol as a nanoglue: Flexible synthesis of composite aerogels SO SCIENCE LA English DT Article ID COLLOIDAL PLATINUM; NANOCOMPOSITE; PARTICLES AB Low-density nanoscale mesoporous composites may be readily synthesized by adding a colloidal or dispersed solid to an about-to-gel silica set. The silica sol can "glue" a range of chemically and physically diverse particles into the three-dimensional silica network formed upon gelation. If the composite gel is supercritically dried so as to maintain the high porosity of the wet gel,:a composite aerogel is formed In which the nanoscopic surface and bulk properties of each component are retained in the solid composite. The,volume fraction of the second solid can be varied above or below a percolation threshold to tune the transport properties of the composite aerogel and thereby design nanoscale materials for chemical, electronic, and optical applications. C1 USN, Res Lab, Washington, DC 20375 USA. RP Rolison, DR (reprint author), USN, Res Lab, Code 6170, Washington, DC 20375 USA. RI Stroud, Rhonda/C-5503-2008 OI Stroud, Rhonda/0000-0001-5242-8015 NR 36 TC 259 Z9 266 U1 25 U2 172 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD APR 23 PY 1999 VL 284 IS 5414 BP 622 EP 624 DI 10.1126/science.284.5414.622 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 190FH UT WOS:000079951100039 ER PT J AU Fender, RP Garrington, ST McKay, DJ Muxlow, TWB Pooley, GG Spencer, RE Stirling, AM Waltman, EB AF Fender, RP Garrington, ST McKay, DJ Muxlow, TWB Pooley, GG Spencer, RE Stirling, AM Waltman, EB TI MERLIN observations of relativistic ejections from GRS 1915+105 SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE accretion, accretion discs; stars : individual : GRS 1915+105; stars : variables : other; ISM : jets and outflows; radio continuum : stars; X-rays : stars ID X-RAY TRANSIENT; SUPERLUMINAL SOURCE; GRS-1915+105; RADIO; VARIABILITY; EMISSION; JETS AB We present high-resolution MERLIN radio images of multiple relativistic ejections from GRS 1915+105 in 1997 October/November. The observations were made at a time of complex radio behaviour, corresponding to multiple optically thin outbursts and several days of rapid radio flux oscillations. This activity followed similar to 20 d of a plateau state of inverted-spectrum radio emission and hard, quasi-stable X-ray emission. The radio imaging resolved four major ejection events from the system. As previously reported from earlier VLA observations of the source, we observe apparent superluminal motions resulting from intrinsically relativistic motions of the ejecta. However, our measured proper motions are significantly greater than those observed on larger angular scales with the VLA. Under the assumption of an intrinsically symmetric ejection, we can place an upper limit on the distance to GRS 1915+105 of 11.2 +/- 0.8 kpc, Solutions for the velocities unambiguously require a higher intrinsic speed by about 0.1c than that derived from the earlier VLA observations, whilst the angle to the line of sight is not found to be significantly different. At a distance of 11 kpc, we obtain solutions of v = 0.98(-0.05)(+0.02) c and theta = 66 degrees +/- 2 degrees, The jet also appears to be curved on a scale that corresponds to a period of around 7 d. We observe significant evolution of the linear polarization of the approaching component, with large rotations in position angle and a general decrease in fractional polarization. This may be the result of increasing randomization of the magnetic field within the ejected component. We do not at any time detect significant linear polarization from the core, including periods when the flux density from this region is dominated by radio oscillations. The power input into the formation of the jet is very large, greater than or equal to 10(38) erg s(-1) 11 kpc for a pair plasma. If the plasma contains a cold proton for each electron, then the mass outflow rate, greater than or equal to 10(18) g s(-1), is comparable to inflow rates previously derived from X-ray spectral fits. C1 Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. Univ Amsterdam, Ctr High Energy Astrophys, NL-1098 SJ Amsterdam, Netherlands. Univ Manchester, Nuffield Radio Astron Labs, Jodrell Bank, Macclesfield SK11 9DL, Cheshire, England. Joint Inst VLBI Europe, NL-7990 AA Dwingeloo, Netherlands. Univ Cambridge, Cavendish Lab, Mullard Radio Astron Observ, Cambridge CB3 0HE, England. USN, Remote Sensing Div, Res Lab, Washington, DC 20375 USA. RP Fender, RP (reprint author), Univ Amsterdam, Astron Inst Anton Pannekoek, Kruislaan 403, NL-1098 SJ Amsterdam, Netherlands. OI Muxlow, Thomas/0000-0001-5797-8796 NR 34 TC 289 Z9 290 U1 1 U2 1 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD APR 21 PY 1999 VL 304 IS 4 BP 865 EP 876 DI 10.1046/j.1365-8711.1999.02364.x PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 194EJ UT WOS:000080178900020 ER PT J AU Gould, RW Arnone, RA Martinolich, PM AF Gould, RW Arnone, RA Martinolich, PM TI Spectral dependence of the scattering coefficient in case 1 and case 2 waters SO APPLIED OPTICS LA English DT Article ID REMOTE-SENSING REFLECTANCE; OPTICAL-EFFICIENCY FACTORS; OCEANIC WATERS; ABSORPTION-COEFFICIENT; NATURAL-WATERS; PARTICULATE; MATTER; LIGHT; COLOR; NM AB An approximate linear relationship between the scattering coefficient and the wavelength of light in the visible is found in case 1 and case 2 waters. From this relationship, we estimate scattering at an unknown wavelength from scattering at a single measured wavelength. This approximation is based on measurements in a 1.5-m-thick surface layer collected with an AC9 instrument at 63 stations in the Arabian Sea, northern Gulf of Mexico, and coastal North Carolina. The light-scattering coefficient at 412 nm ranged from 0.2 to 15.1 m(-1) in these waters, and the absorption coefficient at 412 nm ranged from 0.2 to 4.0 m(-1). A separate data set for 100 stations from Oceanside, California, and Chesapeake Bay, Virginia, was used to validate the relationship. Although the Oceanside waters were considerably different from the developmental data set (based on absorption-to-scattering ratios and single-scattering albedos), the average error between modeled and measured scattering values was 6.0% for the entire test data set over all wavelengths (without regard to sign). The slope of the spectral scattering relationship decreases progressively from high-scattering, turbid waters dominated by suspended sediments to lower-scattering, clear waters dominated by phytoplankton. (C) 1999 Optical Society of America. C1 Stennis Space Ctr, Naval Res Lab, Remote Sensing Applicat Branch, Mississippi State, MS 39529 USA. Neptune Sci Incorp, Slidell, LA 70458 USA. RP Gould, RW (reprint author), Stennis Space Ctr, Naval Res Lab, Remote Sensing Applicat Branch, Code 7343, Mississippi State, MS 39529 USA. EM gould@csips.nrlssc.navy.mil NR 28 TC 81 Z9 89 U1 0 U2 8 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD APR 20 PY 1999 VL 38 IS 12 BP 2377 EP 2383 DI 10.1364/AO.38.002377 PG 7 WC Optics SC Optics GA 186JJ UT WOS:000079725400007 PM 18319803 ER PT J AU Field, CT Millar, PS AF Field, CT Millar, PS TI Laser remote-sensing system analysis for search and rescue SO APPLIED OPTICS LA English DT Article ID STATE DYE-LASER; HOST; ELEMENTS AB We develop a general model of a laser remote-sensing system for search and rescue using targets marked with fluorescent dye. The dye fluoresces at a longer peak wavelength than the incident radiation, enabling a dye-covered target to be distinguished from the unshifted ground echo by the search system. The principal result is a simple expression derived for the average laser power required to search at a particular rate given a required ground energy density. A similar expression is applicable to imaging lidar systems. The example system shown indicates that active probing for lost planes may be practical. C1 USN Acad, Dept Elect Engn, Annapolis, MD 21402 USA. NASA, Goddard Space Flight Ctr, Laser Remote Sensing Branch, Greenbelt, MD 20771 USA. RP Field, CT (reprint author), USN Acad, Dept Elect Engn, Annapolis, MD 21402 USA. EM Pamela.S.Millar.l@gsfc.nasa.gov RI Millar, Pamela/B-4426-2013 NR 22 TC 2 Z9 2 U1 1 U2 4 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD APR 20 PY 1999 VL 38 IS 12 BP 2586 EP 2593 DI 10.1364/AO.38.002586 PG 8 WC Optics SC Optics GA 186JJ UT WOS:000079725400035 PM 18319831 ER PT J AU Aschwanden, MJ Newmark, JS Delaboudiniere, JP Neupert, WM Klimchuk, JA Gary, GA Portier-Fozzani, F Zucker, A AF Aschwanden, MJ Newmark, JS Delaboudiniere, JP Neupert, WM Klimchuk, JA Gary, GA Portier-Fozzani, F Zucker, A TI Three-dimensional stereoscopic analysis of solar active region loops. I. SOHO EIT observations at temperatures of (1.0-1.5) x 10(6) K SO ASTROPHYSICAL JOURNAL LA English DT Article DE sun : activity; sun : corona; sun : UV radiation; techniques : image processing ID STRUCTURES OBSERVING CAMPAIGN; CORONAL DIAGNOSTIC SPECTROMETER; HIGH-RESOLUTION PHOTOGRAPHY; MAGNETIC-FIELDS; EXTREME-ULTRAVIOLET; TEMPORAL VARIATIONS; VLA STEREOSCOPY; SCALING LAW; RAY CORONA; PLASMA AB The three-dimensional structure of solar active region NOAA 7986 observed on 1996 August 30 with the Extreme-Ultraviolet Imaging Telescope (EIT) on board the Solar and Heliospheric Observatory (SOHO) is analyzed. We develop a new method of dynamic stereoscopy to reconstruct the three-dimensional geometry of dynamically changing loops, which allows us to determine the orientation of the mean loop plane with respect to the line of sight, a prerequisite to correct properly for projection effects in three-dimensional loop models. With this method and the filter-ratio technique applied to EIT 171 and 195 Angstrom images we determine the three-dimensional coordinates [x(s), y(s), z(s)], the loop width w(s), the electron density n(e)(s), and the electron temperature T-e(s) as a function of the loop length s for 30 loop segments. Fitting the loop densities with an exponential density model n(e)(h) we iind that the mean of inferred scale height temperatures, T-e(lambda) = 1.22 +/- 0.23 MK, matches closely that of EIT filter-ratio temperatures, T-e(EIT) = 1.21 +/- 0.06 MK. We conclude that these cool and rather large-scale loops (with heights of h approximate to 30-225 Mm) are in hydrostatic equilibrium. Most of the loops show no significant thickness variation w(s), but we measure for most of them a positive temperature gradient (dT/ds > 0) across the first scale height above the footpoint. Based on these temperature gradients we find that the conductive loss rate is about 2 orders of magnitude smaller than the radiative loss rate, which is in strong contrast to hot active region loops seen in soft X-rays. We infer a mean radiative loss time of tau(rad) approximate to 40 minutes at the loop base. Because thermal conduction is negligible in these cool EUV loops, they are nor in steady state, and radiative loss has entirely to be balanced by the heating function. A statistical heating model with recurrent heating events distributed along the entire loop can explain the observed temperature gradients if the mean recurrence time is less than or similar to 10 minutes. We computed also a potential field model (from SOHO/MDI magnetograms) and found a reasonable match with the traced EIT loops. With the magnetic field model we determined also the height dependence of the magnetic field B(h), the plasma parameter beta(h), and the Alfven velocity v(A)(h). No correlation was found between the heating rate requirement E-HO and the magnetic field B-foot at the loop footpoints. C1 Univ Maryland, Dept Astron, College Pk, MD 20742 USA. Space Applicat Corp, Vienna, VA 22180 USA. Univ Paris 11, Inst Astrophys Spatiale, F-91405 Orsay, France. Hughes STX Corp, Lanham, MD 20706 USA. USN, Res Lab, Div Space Sci, Washington, DC 20375 USA. NASA, George C Marshall Space Flight Ctr, Space Sci Lab, Solar Phys Branch ES82, Huntsville, AL 35812 USA. CNRS, Astron Spatiale Lab, F-13376 Marseille 12, France. Swiss Fed Inst Technol, Inst Astron, CH-8092 Zurich, Switzerland. RP Lockheed Martin ATC, Solar & Astrophys Lab, Dept H1 12, Bldg 252,3251 Hanover St, Palo Alto, CA 94304 USA. EM markus@astro.umd.edu RI Klimchuk, James/D-1041-2012 OI Klimchuk, James/0000-0003-2255-0305 NR 77 TC 214 Z9 216 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 1999 VL 515 IS 2 BP 842 EP 867 DI 10.1086/307036 PN 1 PG 26 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 200EW UT WOS:000080527500038 ER PT J AU Dermer, CD Bottcher, M Chiang, J AF Dermer, CD Bottcher, M Chiang, J TI The external shock model of gamma-ray bursts: Three predictions and a paradox resolved SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; gamma rays : theory; radiation mechanisms : nonthermal ID 28 FEBRUARY 1997; AFTERGLOW; EMISSION; EVOLUTION; FIREBALLS; BATSE AB In the external shock model, gamma-ray burst (GRB) emissions are produced by the energization and deceleration of a thin relativistic blast wave that interacts with the circumburst medium (CBM). We study the physical properties of an analytic function that describes temporally evolving GRB spectra in the limit of a smooth CBM with density n(x) proportional to x(-eta), where x is the radial coordinate. The hard-to-soft spectral evolution and the intensity-hardness correlation of GRB peaks are reproduced. We predict that (1) GRB peaks are aligned at high photon energies and lag at low energies according to a simple rule, that (2) temporal indices at the leading edge of a GRB peak display a well-defined shift with photon energy, and that (3) the change in the spectral index values between the leading and trailing edges of a GRB peak decreases at higher photon energies. The reason that GRBs are usually detected with vF(v) peaks in the 50 keV to several MeV range for detectors triggering on peak Aux over a fixed time interval is shown to be a consequence of the inverse cat-relation of the peak flux and the duration of the radiation emitted by decelerating blast waves. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Rice Univ, Dept Space Phys & Astron, Houston, TX 77005 USA. Univ Colorado, JILA, Boulder, CO 80309 USA. RP Dermer, CD (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Code 7653, Washington, DC 20375 USA. NR 34 TC 51 Z9 52 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 1999 VL 515 IS 2 BP L49 EP L52 DI 10.1086/311972 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 200EY UT WOS:000080527700002 ER PT J AU Schmidt, PP AF Schmidt, PP TI Hall model reaction surface for HCN SO INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY LA English DT Article DE HCN; potential energy surface ID ANHARMONIC MOLECULAR VIBRATIONS; ELECTRON-TRANSFER; MATRIX-ELEMENTS; ENERGY; EXPANSIONS; SPECTRUM; H12CP; BOND AB An extended Hall function in exponential basis functions is fit to the accurate potential energy surface for HCN reversible arrow CNH of Murrell et al. [3] and accounts for the linear initial and final states and for the triangular transition state. Reasonable values were also found for the molecular vibrational frequencies in the harmonic limit. (C) 1999 John Wiley & Sons, Inc. C1 Off Naval Res, Phys Sci & Mat Div, Arlington, VA 22217 USA. RP Schmidt, PP (reprint author), Off Naval Res, Phys Sci & Mat Div, Arlington, VA 22217 USA. NR 28 TC 2 Z9 2 U1 0 U2 2 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0020-7608 J9 INT J QUANTUM CHEM JI Int. J. Quantum Chem. PD APR 20 PY 1999 VL 72 IS 5 BP 473 EP 482 DI 10.1002/(SICI)1097-461X(1999)72:5<473::AID-QUA1>3.0.CO;2-3 PG 10 WC Chemistry, Physical; Mathematics, Interdisciplinary Applications; Physics, Atomic, Molecular & Chemical SC Chemistry; Mathematics; Physics GA 176TJ UT WOS:000079167600001 ER PT J AU Marzari, N Vanderbilt, D De Vita, A Payne, MC AF Marzari, N Vanderbilt, D De Vita, A Payne, MC TI Thermal contraction and disordering of the Al(110) surface SO PHYSICAL REVIEW LETTERS LA English DT Article ID ALUMINUM SURFACES; METALS; CU(110); ANHARMONICITY; RELAXATION; DYNAMICS; STRESS; COPPER AB Al(110) has been studied for temperatures up to 900 K via ensemble density-functional molecular dynamics. The strong anharmonicity displayed by this surface results in a negative coefficient of thermal expansion, where the first interlayer distance decreases with increasing temperature. Very shallow channels of oscillation for the second-layer atoms in the direction perpendicular to the surface support this anomalous contraction, and provide a novel mechanism for the formation of adatom-vacancy pairs, preliminary to the disordering and premelting transition. Such characteristic behaviour originates in the free-electron-gas bonding at a loosely packed surface. [S0031-9007(99)08925-5]. C1 Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08854 USA. Univ Trieste, INFM, I-34149 Trieste, Italy. Univ Trieste, Dept Mat Engn & Appl Chem, I-34149 Trieste, Italy. PPH Ecublens, Inst Romand Rech Numer Phys Mat, CH-1015 Lausanne, Switzerland. Univ Cambridge, Cavendish Lab, TCM, Cambridge CB3 0HE, England. RP Marzari, N (reprint author), USN, Res Lab, Ctr Computat Mat Sci, Washington, DC 20375 USA. RI Cavendish, TCM/C-9489-2009; Marzari, Nicola/D-6681-2016; OI Marzari, Nicola/0000-0002-9764-0199; Vanderbilt, David/0000-0002-2465-9091 NR 31 TC 315 Z9 317 U1 3 U2 23 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 19 PY 1999 VL 82 IS 16 BP 3296 EP 3299 DI 10.1103/PhysRevLett.82.3296 PG 4 WC Physics, Multidisciplinary SC Physics GA 186PK UT WOS:000079738000026 ER PT J AU Corral, JL Marti, J Matthews, P Biernacki, P AF Corral, JL Marti, J Matthews, P Biernacki, P TI Electro-optical upconversion in chirped fibre grating based true time delay lines SO ELECTRONICS LETTERS LA English DT Article ID FIBER GRATINGS; ARRAY AB An investigation is presented into the use of an electro-optical upconverting modulation scheme on chirped fibre grating based true time delay lines, and analyses made of both the amplitude and delay of detected microwave signals. The bandwidth limitation of the delay line due to the fibre grating dispersion is clearly improved over that in conventional modulation schemes, while the time delay performance is kept constant (sigma(max) = +/-0.9ps). C1 Univ Politecn Valencia, ETSI Telecomunicac, Valencia 46022, Spain. USN, Res Lab, Washington, DC 20375 USA. RP Corral, JL (reprint author), Univ Politecn Valencia, ETSI Telecomunicac, Camino de Vera S-N, Valencia 46022, Spain. RI MARTI, JAVIER /K-8237-2012; Corral, Juan/N-3950-2014 OI Corral, Juan/0000-0003-0857-5207 NR 4 TC 0 Z9 0 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 APR 15 PY 1999 VL 35 IS 8 BP 651 EP 652 DI 10.1049/el:19990449 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA 193UU UT WOS:000080156200031 ER PT J AU Hobart, KD Kub, FJ AF Hobart, KD Kub, FJ TI Transfer of GaSb thin film to insulating substrate via separation by hydrogen implantation SO ELECTRONICS LETTERS LA English DT Article ID LAYERS AB Thin films of GaSb were transferred to insulating substrates by a combination of wafer bonding and separation by hydrogen ion implantation. Hydrogen ion implantation and exfoliation were successfully exploited to transfer a 240nm thick GaSb film to a glass substrate at temperatures less than or equal to 150 degrees C. A novel room temperature wafer bonding technique utilising an ultraviolet/ozone process was also demonstrated. The films have been characterised by atomic force and scanning electron microscopies. C1 USN, Res Lab, Washington, DC 20375 USA. RP USN, Res Lab, Washington, DC 20375 USA. NR 9 TC 20 Z9 20 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 APR 15 PY 1999 VL 35 IS 8 BP 675 EP 676 DI 10.1049/el:19990477 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA 193UU UT WOS:000080156200047 ER PT J AU Kodama, RH Edelstein, AS AF Kodama, RH Edelstein, AS TI Synthesis and characterization of magnetic nanocomposite films SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc ID COBALT; PARTICLES; CLUSTERS AB Nanocomposite films were made consisting of Co nanoparticles, with coatings of amorphous Al2O3. Nanoparticles were deposited on room-temperature substrates by sputtering in 0.10-0.20 Torr Ar. Transmission electron microscope images showed average Co particle sizes between 70 and 223 Angstrom, for different sputtering rates and pressures. Selected-area electron diffraction and x-ray diffraction showed that the particles had a fcc structure for sizes less than or equal to 122 Angstrom and a mixture of fcc and hcp phases for larger sizes. Magnetization measurements on a sample with 122 Angstrom mean-particle size showed significant hysteresis at room temperature, with a coercivity of 390 Oe. At 10 K, the coercivity increased to 3145 Oe, and a loop shift of 2020 Oe was measured when the sample was field cooled. This indicates a fraction of the Co was oxidized by reaction with the Al2O3 coating, resulting in a surface layer of antiferromagnetic Co oxide. (C) 1999 American Institute of Physics. [S0021-8979(99)50608-7]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Kodama, RH (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 9 TC 31 Z9 32 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 4316 EP 4318 DI 10.1063/1.370354 PN 2A PG 3 WC Physics, Applied SC Physics GA 188MK UT WOS:000079850700013 ER PT J AU Willard, MA Huang, MQ Laughlin, DE McHenry, ME Cross, JO Harris, VG Franchetti, C AF Willard, MA Huang, MQ Laughlin, DE McHenry, ME Cross, JO Harris, VG Franchetti, C TI Magnetic properties of HITPERM (Fe,Co)(88)Zr7B4Cu1 magnets SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc ID HIGH SATURATION MAGNETIZATION; TRANSITION-METAL ALLOYS; M-B M=ZR; FE-ZR-B; GRAIN-SIZE AB A new class of nanocrystalline alloys with composition Fe44Co44Zr7B4Cu1 has been developed. This and similar alloys of general composition (Fe, Co)-M-B-Cu (where M=Zr, Hf, Nb, etc.) have been named HITPERM. They offer large magnetic inductions and excellent soft magnetic properties at elevated temperatures. Thermomagnetic properties, permeability, and frequency dependent losses are described in this report. These alloys exhibit high magnetization that persists to the alpha --> gamma phase transformation at 980 degrees C. Alternating current permeability experiments reveal a high permeability at 2 kHz with a loss value of 1 W/g at B-s = 10 kG and f = 10 kHz. (C) 1999 American Institute of Physics. [S0021-8979(99)52908-3]. C1 Carnegie Mellon Univ, Dept Mat Sci & Engn, Pittsburgh, PA 15213 USA. USN, Res Lab, Washington, DC 20375 USA. Univ Penn, Dept Math, Philadelphia, PA 19104 USA. RP Willard, MA (reprint author), Carnegie Mellon Univ, Dept Mat Sci & Engn, Pittsburgh, PA 15213 USA. RI Willard, Matthew/A-8492-2009; Harris, Vincent/A-8337-2009; McHenry, Michael/B-8936-2009 OI Willard, Matthew/0000-0001-5052-8012; NR 8 TC 100 Z9 107 U1 6 U2 29 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 4421 EP 4423 DI 10.1063/1.369804 PN 2A PG 3 WC Physics, Applied SC Physics GA 188MK UT WOS:000079850700047 ER PT J AU Lubitz, P Cheng, SF AF Lubitz, P Cheng, SF TI Ferromagnetic resonance as a probe of anisotropy in giant magnetoresistance structures SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc ID SPIN-VALVES; FILMS AB The ferromagnetic resonance spectra of thin alloy films, which are often used as components of giant magnetoresistance structures, were observed. Face-centered-cubic films with Cu underlayers and single magnetic layers of permalloy, permalloy containing Co; or Co rich CoFe alloys were deposited by magnetron sputtering. The magnetic field position of the resonance provides information about the magnetic moment and the growth induced anisotropies of the films, and was affected by magnetostriction when stresses were induced. Linewidths and coercivity increased rapidly as a function of the total (Cu+magnet) layer thickness above about 20 nm. The linewidth is sensitive to the damping parameter for the thinner films and to magnetocrystalline anisotropy and crystallographic texture for the thicker Co containing films in which the grains become large. Based on observations of the resonances in stressed films, several nonmagnetostrictive compositions were determined. (C) 1999 American Institute of Physics. [S0021-8979(99)53008-9]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Lubitz, P (reprint author), USN, Res Lab, Washington, DC 20375 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 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 4556 EP 4558 DI 10.1063/1.370406 PN 2A PG 3 WC Physics, Applied SC Physics GA 188MK UT WOS:000079850700093 ER PT J AU Soulen, RJ Osofsky, MS Nadgorny, B Ambrose, T Broussard, P Cheng, SF Byers, J Tanaka, CT Nowack, J Moodera, JS Laprade, G Barry, A Coey, MD AF Soulen, RJ Osofsky, MS Nadgorny, B Ambrose, T Broussard, P Cheng, SF Byers, J Tanaka, CT Nowack, J Moodera, JS Laprade, G Barry, A Coey, MD TI Andreev reflection: A new means to determine the spin polarization of ferromagnetic materials SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc AB We have developed a simple method to measure the transport spin polarization of ferromagnetic materials. This technique relies on the fact that the Andreev reflection process at the interface between a superconductive and normal is influenced by the spin polarization P of the normal metal. In a very short time we have been able to measure the spin polarization of several metals: NixFe1-x, Ni, Co, Fe, NiMnSb, La0.7Sr0.3MnO3, and CrO2, whose spin polarization ranges from 35% to 90%. Our results compare well with other methods for measuring P. (C) 1999 American Institute of Physics. [S0021-8979(99)25208-5]. C1 USN, Res Lab, Washington, DC 20375 USA. George Washington Univ, Washington, DC 20052 USA. MIT, Francis Bitter Natl Magnet Lab, Cambridge, MA 02139 USA. INSA, Toulouse, France. Univ Dublin Trinity Coll, Dept Phys, Dublin 2, Ireland. RP Soulen, RJ (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Osofsky, Michael/A-1050-2010 NR 7 TC 70 Z9 71 U1 0 U2 10 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 4589 EP 4591 DI 10.1063/1.370417 PN 2A PG 3 WC Physics, Applied SC Physics GA 188MK UT WOS:000079850700104 ER PT J AU Osgood, RM Sinha, SK Freeland, JW Idzerda, YU Bader, SD AF Osgood, RM Sinha, SK Freeland, JW Idzerda, YU Bader, SD TI X-ray scattering from magnetic, rough surfaces SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc AB We present expressions for the resonant magnetic x-ray scattering from rough surfaces; using our formulas we analyze the structural and magnetic roughnesses, as well as the correlation between them. We demonstrate that the leading contribution to the difference in the diffuse scattering between left- and right-circularly polarized light for a rough surface with in-plane magnetization vanishes unless the structural and magnetic roughnesses are correlated. The effects of magnetic domain structure and magnetic dead layers on the surface scattering are also discussed. (C) 1999 American Institute of Physics. [S0021-8979(99)70108-8]. C1 Argonne Natl Lab, Argonne, IL 60439 USA. USN, Res Lab, Div Sci Mat, Washington, DC 20379 USA. RP Osgood, RM (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Bader, Samuel/A-2995-2013 NR 9 TC 35 Z9 35 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 4619 EP 4621 DI 10.1063/1.370426 PN 2A PG 3 WC Physics, Applied SC Physics GA 188MK UT WOS:000079850700113 ER PT J AU Oliver, SA Chen, ML Vittoria, C Lubitz, P AF Oliver, SA Chen, ML Vittoria, C Lubitz, P TI Properties of pulsed laser deposited scandium-doped barium hexaferrite films SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc ID FERRITES AB The properties of thin films of BaSc(x)Fe(12-)xO(19) (x = 0.4) were determined by structural and magnetic measurements. Films were deposited by pulsed laser ablation deposition onto c-plane sapphire at oxygen pressures between 10 and 100 mTorr. X-ray diffraction measurements showed all films to be single-phase c-axis oriented hexaferrites with expanded c-axis lattice constants compared to x = 0 films. Magnetometry measurements showed that all films had the easy axis (c-axis) normal to the film plane, with a mean saturation magnetization value of 3.8 kG. The mean uniaxial anisotropy field value was 10.6 kOe. This ability to adjust the uniaxial anisotropy field in hexaferrite films through selective substitution will be important for future planar microwave devices. (C) 1999 American Institute of Physics. [S0021-8979(99)42208-X]. C1 Northeastern Univ, Ctr Electromagnet Res, Boston, MA 02115 USA. Northeastern Univ, Dept Elect & Comp Engn, Boston, MA 02115 USA. USN, Res Lab, Washington, DC 20375 USA. RP Oliver, SA (reprint author), Northeastern Univ, Ctr Electromagnet Res, Boston, MA 02115 USA. NR 12 TC 22 Z9 22 U1 0 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 4630 EP 4632 DI 10.1063/1.370430 PN 2A PG 3 WC Physics, Applied SC Physics GA 188MK UT WOS:000079850700117 ER PT J AU Lubitz, P Cheng, SF Bussmann, K Prinz, GA Krebs, JJ Daughton, JM Wang, D AF Lubitz, P Cheng, SF Bussmann, K Prinz, GA Krebs, JJ Daughton, JM Wang, D TI Structures with improved magnetic characteristics for giant magnetoresistance applications SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc ID MULTILAYERS; EXCHANGE; STORAGE AB Giant magnetoresistance (GMR) structures of various thicknesses with layers of different commonly used fcc NiCoFe alloys and Cu layers were made and several approaches aimed at improving their magnetic properties were investigated. Atomic force microscopy was used to observe roughness and grain size; x-ray diffraction indicated crystalline orientation. Vibrating sample magnetometry was the principal method used to observe the magnetic characteristics. Roughness increased for thicker layers, but in itself did not strongly degrade magnetic switching. Grain size also increased with thickness and was found to correlate strongly with poor switching for Co rich alloys. Because these alloys have large magnetocrystalline anisotropy, larger grains apparently act more independently, leading to increased coercivity and slow saturation. Strategies were implemented that achieved small grain size even in thick structures and therefore resulted in abrupt switching in low fields and in higher remanent magnetization. Thin Fe, Cr and especially Ta interlayers were found to be effective in suppressing grain growth and maintaining [111] texture. This significantly improved the switching for structures containing significant amounts of Co. Even for rough GMR structures with >100 nm thickness the coercivity could be reduced by roughly an order of magnitude by use of 0.5 nm Ta interlayers. (C) 1999 American Institute of Physics. [S0021-8979(99)48808-5]. C1 USN, Res Lab, Washington, DC 20375 USA. Nonvolatile Elect Inc, Eden Prairie, MN 55344 USA. RP Lubitz, P (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 12 TC 15 Z9 15 U1 1 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 5027 EP 5029 DI 10.1063/1.370080 PN 2A PG 3 WC Physics, Applied SC Physics GA 188MK UT WOS:000079850700250 ER PT J AU Ambrose, T Krebs, JJ Bussmann, K Prinz, GA AF Ambrose, T Krebs, JJ Bussmann, K Prinz, GA TI Magnetic and structural properties of face-centered-cubic FexCo1-x alloys on diamond SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc ID FILMS; TRANSITION; GROWTH; CO AB Molecular beam epitaxy has been used to stabilize FexCo1-x alloy films over the entire composition range on diamond (100) substrates. Below a critical thickness, the films are single crystal face-centered-cubic (fcc) as determined from reflection high energy electron diffraction. Superconducting quantum interference device magnetometry studies reveal a nonmonotonic increase in the magnetization of the fcc alloys with Fe concentration, while ferromagnetic resonance indicates a small magnetic anisotropy for x>20%. (C) 1999 American Institute of Physics. [S0021-8979(99)64808-3]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Ambrose, T (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 14 TC 5 Z9 5 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 5066 EP 5068 DI 10.1063/1.370092 PN 2A PG 3 WC Physics, Applied SC Physics GA 188MK UT WOS:000079850700262 ER PT J AU Fatemi, DJ Harris, VG Chen, MX Malik, SK Yelon, WB Long, GJ Mohan, A AF Fatemi, DJ Harris, VG Chen, MX Malik, SK Yelon, WB Long, GJ Mohan, A TI X-ray absorption, neutron diffraction, and Mossbauer effect studies of MnZn-ferrite processed through high-energy ball milling SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc ID FINE-STRUCTURE; ZINC FERRITE AB MnZn-ferrite has been prepared via high-energy ball milling of elemental oxides MnO, ZnO, and alpha-Fe2O3. Neutron diffraction measurements suggest a high density of vacancies in a spinel structure. The spinel phase appears to comprise 99.8 wt% of the material in the sample milled for 40 h, with the remainder attributable to unreacted alpha-Fe2O3. The x-ray absorption near-edge structure was analyzed to provide an understanding of the charge state of the constituent Fe ions. This analysis reveals about 2/3 of Fe cations to be trivalent, increasing to about 3/4 after a 5 h anneal at 450 degrees C. The heat treatment is also observed to induce a cation redistribution in the ball-milled ferrite toward that of a standard processed via ceramics methods. Results from Mossbauer spectroscopy determine the average hyperfine fields in the sample milled 40 h to be 289 and 487 kOe at 295 and 78 K, respectively. The average isomer shift is 0.32 mm/s at 295 K and 0.46 mm/s at 78 K, values which are typical of iron (III) in a spinel oxide lattice. As expected for a cubic-like environment, the quadrupole shifts are very small, ranging from 0.07 mm/s at 295 K to 0.00 mm/s at 78 K. (C) 1999 American Institute of Physics. [S0021-8979(99)76708-3]. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Missouri Res Reactor, Columbia, MO 65211 USA. Univ Missouri, Dept Chem, Rolla, MO 65409 USA. RP Fatemi, DJ (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Harris, Vincent/A-8337-2009 NR 15 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 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 5172 EP 5174 DI 10.1063/1.369114 PN 2A PG 3 WC Physics, Applied SC Physics GA 188MK UT WOS:000079850700296 ER PT J AU Carpenter, EE O'Connor, CJ Harris, VG AF Carpenter, EE O'Connor, CJ Harris, VG TI Atomic structure and magnetic properties of MnFe2O4 nanoparticles produced by reverse micelle synthesis SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc ID ABSORPTION FINE-STRUCTURE; NIZN-FERRITE FILMS; CATION DISTRIBUTION AB Using the aqueous cores of reverse micelles as nanoreactors, nanoparticles (d similar to 10 nm) of the mixed ferrite MnFe2O4 were produced. Seven processing trials were performed where the concentration of ammonium hydroxide, reaction temperature, and the oxidizing agent were varied. All trials result in Mn-ferrite particles with varying chemistry and structure. The Mn concentration in the resulting ferrite is strongly enhanced by both the presence of H2O2 as an oxidizing agent and a surplus of ammonium hydroxide. The increased Mn concentration correlates with a higher fraction of octahedrally coordinated Mn cations. When near-stoic amounts of ammonium hydroxide are used, the resulting ferrites are nearly stoichiometric with a more equitable distribution of Mn cations on the octahedral and tetrahedral sublattices. In all ferrite nanoparticles, the Mn cations have a preference for octahedral site occupancy that is larger than the 20% measured in bulk Mn-ferrite. We attribute the cation filling trends to the stabilization of excess trivalent Mn during processing. (C) 1999 American Institute of Physics. [S0021-8979(99)17708-9]. C1 Univ New Orleans, Adv Mat Res Inst, New Orleans, LA 70148 USA. USN, Res Lab, Washington, DC 20375 USA. RP Carpenter, EE (reprint author), Univ New Orleans, Adv Mat Res Inst, New Orleans, LA 70148 USA. RI Harris, Vincent/A-8337-2009; Carpenter, Everett/A-2797-2010 OI Carpenter, Everett/0000-0002-3497-0318 NR 11 TC 48 Z9 50 U1 0 U2 13 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 5175 EP 5177 DI 10.1063/1.369115 PN 2A PG 3 WC Physics, Applied SC Physics GA 188MK UT WOS:000079850700297 ER PT J AU Harris, VG Fatemi, DJ Hathaway, KB Huang, Q Mohan, A Long, GJ AF Harris, VG Fatemi, DJ Hathaway, KB Huang, Q Mohan, A Long, GJ TI Atomic structure and magnetism of ordered and disordered Al0.5Fe0.5-xMnx alloys SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc AB The equiatomic FeAl alloy has been modified by partial substitution of Mn for Fe, and its magnetic and structural properties investigated by neutron diffraction (ND), x-ray absorption fine structure (XAFS) spectroscopy, Mossbauer spectroscopy (MS), and SQUID magnetometry both for the ordered (B2) and disordered states. The unit cell volume is measured to increase linearly with Mn concentration. XAFS measurements indicate local structural displacements occur at the Mn sites in both ordered and disordered states that may act to frustrate long-range magnetic order (LRMO). Although MS and ND show no evidence of LRMO, SQUID magnetometry indicates an induced movement in the ordered state that increases with disorder but does not saturate at fields up to 5 T. (C) 1999 American Institute of Physics. [S0021-8979(99)15408-2]. C1 USN, Res Lab, Washington, DC 20375 USA. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. Univ Missouri, Dept Chem, Rolla, MO 65409 USA. RP Harris, VG (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Harris, Vincent/A-8337-2009 NR 10 TC 2 Z9 2 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 5181 EP 5183 DI 10.1063/1.369117 PN 2A PG 3 WC Physics, Applied SC Physics GA 188MK UT WOS:000079850700299 ER PT J AU Rachford, FJ Levy, M Osgood, RM Kumar, A Bakhru, H AF Rachford, FJ Levy, M Osgood, RM Kumar, A Bakhru, H TI Magnetization and ferromagnetic resonance studies in implanted and crystal ion sliced bismuth-substituted yttrium iron garnet films SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc ID FMR LINEWIDTH; GAAS AB Bismuth-substituted yttrium iron garnet (Bi-YIG) is the material of choice in the fabrication of optical isolators. Recently some of us have demonstrated an ion-implantation based technique for detaching single-crystal Bi-YIG films from their gadolinium gallium garnet growth substrates, and for their subsequent bonding onto semiconductor wafers. In this article we study the magnetic properties of bubble-type Bi-YIG films with large out-of-plane uniaxial anisotropy in various stages of the separation process. We find that the implantation reduces the perpendicular anisotropy field from approximately 1435 to 750 Oe as a result of increased residual strain. Annealing partially restores the anisotropy to 900 Oe depending on annealing conditions. Chemical etching of the implanted sample separates the Bi-YIG film from the substrate at the sacrificial layer. Upon detachment the perpendicular anisotropy of the sample is nearly fully restored to its original value. The 9 GHz ferromagnetic resonance (FMR) linewidth of these films is large (440-520 Oe) and is only weakly affected by the processing. (C) 1999 American Institute of Physics. [S0021-8979(99)16808-7]. C1 USN, Res Lab, Mat Phys Branch, Washington, DC 20375 USA. Columbia Univ, Microelect Sci Labs, New York, NY 10027 USA. SUNY Albany, Dept Phys, Albany, NY 12222 USA. RP Rachford, FJ (reprint author), USN, Res Lab, Mat Phys Branch, Code 6343, Washington, DC 20375 USA. NR 7 TC 8 Z9 8 U1 1 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 5217 EP 5219 DI 10.1063/1.369948 PN 2A PG 3 WC Physics, Applied SC Physics GA 188MK UT WOS:000079850700311 ER PT J AU Broussard, PR Browning, VM Cestone, VC AF Broussard, PR Browning, VM Cestone, VC TI X-ray photoemission characterization of La-0.67(CaxSr1-x)(0.33)MnO3 films SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc ID SPECTROSCOPY; LA1-XSRXMNO3 AB The Curie temperature and x-ray photoemission spectra of thin films of La-0.6(7)(CaxSr1-x)(0.33)MnO3 have been studied as a function of the Ca/Sr ratio. The films were grown by off-axis cosputtering from individual targets of La0.67Ca0.33MnO3 (LCMO) and La0.67Sr0.33MnO3 (LSMO) onto (100) oriented NdGaO3 substrates. The films grow with a (100) orientation, with no other orientations observed by x-ray diffraction. For the alloy mixtures, the Curie temperature, T-C, varies slowly as the Ca/Sr is decreased, remaining approximate to 300 K, while for the LCMO and LSMO films T-C is 260 and 330 K, respectively. The Mn-O valence structure is composed of two dominant peaks, whose positions undergo a change as the Ca fraction is decreased. The core lines behave as linear combinations of lines from pure LCMO and LSMO. [S0021-8979(99)20008-4]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Broussard, PR (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 9 TC 5 Z9 5 U1 1 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 5414 EP 5416 DI 10.1063/1.369995 PN 2B PG 3 WC Physics, Applied SC Physics GA 188NF UT WOS:000079853500046 ER PT J AU Osofsky, MS Nadgorny, B Soulen, RJ Broussard, P Rubinstein, M Byers, J Laprade, G Mukovskii, YM Shulyatev, D Arsenov, A AF Osofsky, MS Nadgorny, B Soulen, RJ Broussard, P Rubinstein, M Byers, J Laprade, G Mukovskii, YM Shulyatev, D Arsenov, A TI Measurement of the spin polarization of LaSrMnO SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc AB A new method for determining the transport spin polarization, point contact tunneling from a low temperature superconductor into a ferromagnet, is used to determine the spin polarization of several LaSrMnO thin films and crystals. The Andreev process and its utility in measurements of spin-polarization are described. Preliminary results for the spin polarization of LSMO are presented. (C) 1999 American Institute of Physics. [S0021-8979(99)20408-2]. C1 USN, Res Lab, Washington, DC 20375 USA. George Washington Univ, Washington, DC USA. INSA, Toulouse, France. Moscow State Steel & Alloys Inst, Moscow, Russia. RP Osofsky, MS (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Osofsky, Michael/A-1050-2010; Shulyatev, Dmitry/M-7278-2014 OI Shulyatev, Dmitry/0000-0002-7642-0277 NR 9 TC 15 Z9 15 U1 0 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 5567 EP 5569 DI 10.1063/1.369888 PN 2B PG 3 WC Physics, Applied SC Physics GA 188NF UT WOS:000079853500096 ER PT J AU Rubinstein, M AF Rubinstein, M TI Exchange coupling between two magnetic films separated by an antiferromagnetic spacer SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc ID ANISOTROPY; MODEL AB An expression for the interaction strength between two magnetic films separated by an insulating antiferromagnet spacer has been derived as a function of temperature and thickness. We consider the mechanism wherein the magnetic interaction between the ferromagnetic layers is mediated by the intervening antiferromagnetic insulator via the Suhl-Nakamura (SN) interaction. The interaction energy per unit area, sigma(SN), is derived as sigma(SN) = 1/8(J(C)(2)/J(AF))(delta/a)exp(-t/delta). Here, J(AF) is the magnetic coupling constant between nearest-neighbor antiferromagnetic spins in the spacer, J(C) is the effective coupling constant (which is greatly reduced from the Heisenberg exchange constant), between the spins in the ferromagnetic film and the nearest-neighbor spins in the antiferromagnetic spacer, t is the separation of the two ferromagnetic plates, and delta is the width of an antiferromagnetic domain wall. This mechanism is the antiferromagnetic analog of the Ruderman-Kittel oscillatory coupling between two magnetic films separated by a normal metal. [S0021-8979(99)67608-3]. C1 USN, Res Lab, Washington, DC 20375 USA. RP Rubinstein, M (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 13 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 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 5880 EP 5882 DI 10.1063/1.369901 PN 2B PG 3 WC Physics, Applied SC Physics GA 188NF UT WOS:000079853500195 ER PT J AU Edelstein, AS Kodama, RH Miller, M Browning, V Lubitz, P Sieber, H AF Edelstein, AS Kodama, RH Miller, M Browning, V Lubitz, P Sieber, H TI Ferromagnetic/antiferromagnetic structures with ferromagnetic interlayer coupling SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc ID SUPERLATTICES; MULTILAYERS; FILMS AB Multilayer samples and structures composed of NiO(t)/Co(2.5 nm)/NiO(t)/Py(2.5 nm)/NiO( t) with t = 6.6 and 13.2 nm exhibit ferromagnetic interlayer coupling below 400 K. A crossover is observed between the behavior near 300 K and at 10 K in ferromagnetic(F)/antiferromagnetic(AF) structures. Effects observed near 300 K, but not at 10 K, are an enhancement of Hc and the M-H loop squareness in F/AF multilayers as one increases the number of layers. A possible explanation for the crossover is given based on the domain wall thickness becoming less than the AF film thickness. (C) 1999 American Institute of Physics. [S0021-8979(99)67808-2]. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Wisconsin, Dept Mat Sci & Engn, Madison, WI 53705 USA. RP Edelstein, AS (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 14 TC 2 Z9 2 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 5886 EP 5888 DI 10.1063/1.369903 PN 2B PG 3 WC Physics, Applied SC Physics GA 188NF UT WOS:000079853500197 ER PT J AU Chu, SY Kline, C Huang, MQ McHenry, ME Cross, J Harris, VG AF Chu, SY Kline, C Huang, MQ McHenry, ME Cross, J Harris, VG TI Preparation, characterization and magnetic properties of an ordered FeCo single crystal SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc AB Pristine FeCo single crystals with millimeter dimensions were prepared by annealing FeCo ingot samples. The composition and microstructure of a fine polished cylindrical single crystal specimen used in this work were characterized by energy dispersive x-ray analysis, scanning electron microscopy, back-reflection Laue diffraction photographs, and x-ray diffraction (XRD). The ordered alpha' phase in the specimen was detected by XRD experiments using the synchrotron light source at Brookhaven National Laboratory. The full width at half maximum of the superlattice line, i.e., the (100) reflection, in phi scan was 2.5 degrees. The magnetic field dependence of the magnetic moment was measured with the field oriented in different directions using a superconducting quantum interference device magnetometer and a vibrating sample magnetometer. (C) 1999 American Institute of Physics. [S0021-8979(99)17308-0]. C1 Carnegie Mellon Univ, Dept Mat Sci & Engn, Pittsburgh, PA 15213 USA. USN, Res Lab, Washington, DC 20375 USA. RP Chu, SY (reprint author), Carnegie Mellon Univ, Dept Mat Sci & Engn, Pittsburgh, PA 15213 USA. RI Harris, Vincent/A-8337-2009; McHenry, Michael/B-8936-2009 NR 10 TC 16 Z9 17 U1 0 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 6031 EP 6033 DI 10.1063/1.369072 PN 2B PG 3 WC Physics, Applied SC Physics GA 188NF UT WOS:000079853500245 ER PT J AU Ambrose, T Liu, K Chien, CL AF Ambrose, T Liu, K Chien, CL TI Doubly exchange-biased NiCoO/NiFe/Cu/NiFe/NiCoO spin valves SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc ID GIANT MAGNETORESISTANCE; SUPERLATTICES; DEPENDENCE; TRILAYERS; BILAYERS; COO AB A new type of doubly exchange-biased Ni50Co50O/NiFe/Cu/NiFe/Ni30Co70O spin-valve structure, with two ferromagnetic layers exchange biased in opposite directions by two different antiferromagnetic layers is demonstrated. By field cooling in magnetic fields of opposite directions, the resultant hysteresis loop consists of two loops shifted in opposite directions from the zero magnetic field. The NiFe layers are in the antiparallel state in zero magnetic field, and the switching to the parallel state can be tuned by varying the exchange bias. The modified spin valves also show potential for suppressed Barkhausen noise. (C) 1999 American Institute of Physics. [S0021-8979(99)33908-6]. C1 Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. RP Ambrose, T (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Liu, Kai/B-1163-2008 OI Liu, Kai/0000-0001-9413-6782 NR 15 TC 6 Z9 6 U1 0 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 6124 EP 6126 DI 10.1063/1.370282 PN 2B PG 3 WC Physics, Applied SC Physics GA 188NF UT WOS:000079853500276 ER PT J AU Mazin, II Singh, DJ Ambrosch-Draxl, C AF Mazin, II Singh, DJ Ambrosch-Draxl, C TI Transport, optical and electronic properties of the half metal CrO2 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc ID FERROMAGNET AB The half metal ferromagnet CrO2 has interesting and unusual electronic properties. As in many other cases when kinetic properties are not easily described by the conventional Bloch-Boltzmann theory, strong correlation effects of the Hubbard type were called for explanation of the electronic properties of CrO2. Here we report detailed analysis of the electronic structure and related properties of CrO2, based on state-of-the-art density functional calculations. We conclude that (1) the most current experimental data do not indicate an anomalously large mass renormalization, (2) temperature dependence of the resistivity is due mainly to the scattering by spin fluctuations, (3) coupling between charge (electrons) and spin (magnons) degrees of freedom is anomalously strong, (4) recent optical measurements can be reasonably interpreted within the quasi-one-electron density functional calculations, and (5) their deviation from the experiment is opposite to that expected in the Hubbard model, and agrees with a physical picture of electrons dressed by spin fluctuations. (C) 1999 The American Physical Society. [S0556-2821(99)03904-1]. C1 USN, Res Lab, Washington, DC 20375 USA. Graz Univ, Inst Theoret Phys, A-8010 Graz, Austria. RP Mazin, II (reprint author), USN, Res Lab, Code 6691, Washington, DC 20375 USA. RI Mazin, Igor/B-6576-2008; Singh, David/I-2416-2012; Draxl, Claudia/O-6189-2016 OI Draxl, Claudia/0000-0003-3523-6657 NR 10 TC 8 Z9 8 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 6220 EP 6222 DI 10.1063/1.370227 PN 2B PG 3 WC Physics, Applied SC Physics GA 188NF UT WOS:000079853500308 ER PT J AU Cullen, JR Wun-Fogle, M Teter, JP Restorff, JB Clark, AE AF Cullen, JR Wun-Fogle, M Teter, JP Restorff, JB Clark, AE TI Magnetization and magnetostriction of Tb1-xDyxZn single crystals SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc AB Magnetization, magnetostriction, and elastic modulus measurements were made on single crystal specimens of Tb1-xDyxZn. Easy axis magnetization rotation as much as 26 degrees were observed in the (001) plane of Tb0.75Dy0.25Zn below 33 K. From these measurements, values of the K-4/K-8 anisotropy ratios were calculated. No easy axis magnetization rotation was observed in the x=0.6 and x=0.8 single crystals. Magnetostriction and modulus measurements at 77 K in Tb0.4Dy0.6Zn showed a saturation magnetostriction of similar to 5x10(-3) and a maximum magnetomechanical coupling factor of 0.96. (C) 1999 American Institute of Physics. [S0021-8979(99)23308-7]. C1 USN, Ctr Surface Warfare, Carderock Div, W Bethesda, MD 20817 USA. Clark Associates, Adelphi, MD 20783 USA. RP Cullen, JR (reprint author), USN, Ctr Surface Warfare, Carderock Div, Code 684, W Bethesda, MD 20817 USA. NR 8 TC 9 Z9 9 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 6250 EP 6252 DI 10.1063/1.370236 PN 2B PG 3 WC Physics, Applied SC Physics GA 188NF UT WOS:000079853500317 ER PT J AU Wun-Fogle, M Restorff, JB Clark, AE AF Wun-Fogle, M Restorff, JB Clark, AE TI Hysteresis and magnetostriction of TbxDyyHo1-x-yFe1.95 [112] dendritic rods SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc ID ANISOTROPY AB The magnetization and magnetostriction of a variety of 3/16-in.-diam Laves phase rods of Tb(x)Dy(y)Ho(1-x)2(y)Fe(1.95) grown in the form of [112] oriented dendritic compounds were measured as a function of applied magnetic field -3000 v = 1) is much larger for j = 4 than for j = 0, and the m(j)-dependence of P(v = 0,j = 4,m(j) --> v = 1) is markedly different from that of the initial-state-resolved reaction probability. For all but the highest collision energies, vibrational excitation from the (v = 0,j = 4) state is accompanied by loss of rotational energy, in agreement with results of molecular beam experiments on scattering of H-2 and D-2 from Cu(111). (C) 1999 American Institute of Physics. C1 Leiden Univ, Gorlaeus Labs, Leiden Inst Chem, NL-2300 RA Leiden, Netherlands. Free Univ Amsterdam, NL-1081 HV Amsterdam, Netherlands. USN, Res Lab, Theoret Chem Sect, Washington, DC 20375 USA. RP Leiden Univ, Gorlaeus Labs, Leiden Inst Chem, POB 9502, NL-2300 RA Leiden, Netherlands. EM mccormac@chem.leidenuniv.nl RI Baerends, Evert Jan/F-7206-2011 OI Baerends, Evert Jan/0000-0002-3045-4906 NR 64 TC 49 Z9 49 U1 0 U2 8 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 8 PY 1999 VL 110 IS 14 BP 7008 EP 7020 DI 10.1063/1.478606 PG 13 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 183ER UT WOS:000079541700044 ER PT J AU Roland, CM Santangelo, PG Antonietti, M Neese, M AF Roland, CM Santangelo, PG Antonietti, M Neese, M TI Mechanical behavior of polystyrene microgels SO MACROMOLECULES LA English DT Article ID MOLECULAR-WEIGHT DEPENDENCE; TEMPERATURE-DEPENDENCE; DIELECTRIC-RELAXATION; SEGMENTAL RELAXATION; THERMORHEOLOGICAL COMPLEXITY; VISCOELASTIC BEHAVIOR; POLYMERS; POLYISOPRENE; DYNAMICS; NETWORKS AB Polystyrene microgels are nanometer-sized particles produced by polymerization and crosslinking in microemulsion. As a result of their internal network structure, microgels have negligible intermolecular entanglement interactions. This can have a profound effect on their rheology; it also leads to glassy fracture resembling the behavior of low molecular weight, linear polystyrene. At higher frequencies, the mechanical response of microgels is quite similar to that of linear polystyrene. Breakdown of time-temperature superpositioning occurs in the softening zone of the viscoelastic spectrum. In the glass transition region, the segmental relaxation function is broadened and exhibits an enhanced dependence on temperature. The latter two effects, due to the cross-linking of the microgels, are also seen in conventional, macroscopic networks. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. Max Planck Inst Colloids & Interfaces, D-14513 Teltow, Germany. RP Roland, CM (reprint author), USN, Res Lab, Div Chem, Code 6120, Washington, DC 20375 USA. NR 49 TC 16 Z9 16 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD APR 6 PY 1999 VL 32 IS 7 BP 2283 EP 2287 DI 10.1021/ma9817828 PG 5 WC Polymer Science SC Polymer Science GA 184XD UT WOS:000079638300026 ER PT J AU Wilson, T Baugh, R AF Wilson, T Baugh, R TI Naval EarthMap Observer (NEMO) program and the Naval Space Science and Technology Program Office SO ACTA ASTRONAUTICA LA English DT Article ID AVIRIS AB In February 1997 the Chief of Naval Research chartered the Naval Space Science and Technology (S&T) Program Office, at the Office of Naval Research, to operate as the central point of contact for the Department of the Navy's (DON's) S&T activities in space. The Office was chartered to enhance the DON's space efforts through interdepartmental integration and linkage with external Department of Defense (DOD) commands and government agencies. The Office's goal is to optimize a plan for S&T coherency, synergy, and relevancy to effect technology transition to the DON's Systems Commands or Program Executive Offices (PEO's) while developing an investment strategy that accommodates and leverages the commonality of commercial and consumer thrust areas and products. This paper will focus on the "Flagship" Naval Space S&T Program, the Naval EarthMap Observer (NEMO) Program, as one example of how the Office is executing its mission. It will discuss how, through NEMO, the Navy is able to lever-age commercial industry and other US government agency requirements and resources to meet unique Naval needs. Finally, the paper will discuss the specifics of NEMO, the Navy's roles and responsibilities and how the Navy will use NEMO in its mission to characterize the littoral regions of the world. Through the NEMO satellite system, the Navy will develop a large hyperspectral imagery database which will be used to characterize and model the littoral regions of the world. NEMO will provide images using its Coastal Ocean Imaging Spectrometer (COIS) Instrument along with a co-registered 5m Panchromatic Imager (PIC). With 210 spectral channels over a bandpass of 0.4 to 2.5 mu m and very high signal-to-noise ratio (SNR), the COIS instrument is optimized for the low reflectance environment of the littoral region. COIS will image over a 30km wide swath with a 60m Ground Sample Distance (GSD), and can image at a 30m GSD with ground motion compensation. A 10:30am, sun-synchronous circular orbit of 605km enables continuous repeat coverage of the whole earth. A unique aspect of the system is the spectral feature extraction and data compression software algorithm developed by the Naval Research Laboratory (NRL) called the Optical Real-Time Spectral Identification System (ORASIS). ORASIS employs a parallel, adaptive hyperspectral method for real-time scene characterization, data reduction, background suppression, and target recognition. The use of ORASIS is essential for management of the massive amounts of data expected from the NEMO HSI system, and for development of Naval products. Specific Naval products include bathymetry, water clarity, bottom type, atmospheric visibility, bioluminescence, beach characterization, underwater hazards, total column atmospheric water vapor, and detection and mapping of sub-visible cirrus. Demonstrations of timely downlinks of real-time hyperspectral imagery data to the Naval warfighter are also being developed. The NEMO satellite is planned for launch in mid-2000 followed by an operational period of 3 to 5 years. Published by Elsevier Science Ltd. C1 USN, Res Lab, Washington, DC 20375 USA. RP Wilson, T (reprint author), USN, Res Lab, 4555 Overlook Ave SW, Washington, DC 20375 USA. NR 10 TC 1 Z9 1 U1 0 U2 1 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 APR-JUN PY 1999 VL 44 IS 7-12 SI SI BP 675 EP 683 DI 10.1016/S0094-5765(99)00061-2 PG 9 WC Engineering, Aerospace SC Engineering GA 235RB UT WOS:000082555400038 ER PT J AU Moore, D AF Moore, D TI Protective finishing systems for Navy aircraft SO ADVANCED MATERIALS & PROCESSES LA English DT Article AB The Navy is developing a range of protective coatings that comply with environmental directives, reduce costs, and extend the life of aircraft structures. C1 USN, Air Syst Command, Aerosp Mat Div, Patuxent River, MD 20670 USA. RP Moore, D (reprint author), USN, Air Syst Command, Aerosp Mat Div, 48066 Shaw Rd,Bldg 2188,MS5, Patuxent River, MD 20670 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 0026-0665 J9 ADV MATER PROCESS JI Adv. Mater. Process. PD APR PY 1999 VL 155 IS 4 BP 31 EP 34 PG 4 WC Materials Science, Multidisciplinary SC Materials Science GA 184DZ UT WOS:000079596200004 ER PT J AU Heath, ME Ridgway, SH AF Heath, ME Ridgway, SH TI How dolphins use their blubber to avoid heat stress during encounters with warm water SO AMERICAN JOURNAL OF PHYSIOLOGY-REGULATORY INTEGRATIVE AND COMPARATIVE PHYSIOLOGY LA English DT Article DE Tursiops truncatus; bottlenose dolphin; core temperature; heat flow; heat storage ID TURSIOPS-TRUNCATUS; TEMPERATURE REGULATION; TESTES; EXERCISE AB Dolphins have been observed swimming in inshore tropical waters as warm as 36-38 degrees C. A simple protocol that mimicked the thermal conditions encountered by a dolphin moving from cool pelagic to warm inshore water was used to determine how dolphins avoid hyperthermia in water temperatures (T-w) at and above their normal core temperature (T-c). T-w (2 sites), rectal temperature (T-re; 3 depths), and skin temperature (T-sk; 7 sites) and rate of heat flow (4-5 sites) between the skin and the environment were measured while the dolphin rested in a chamber during a 30-min baseline and 40-60 min while water was warmed at similar to 0.43 degrees C/min until temperatures of 34-36 degrees C were attained. Instead of the expected increase, T-re consistently showed declines during the warming ramp, sometimes by amounts that were remarkable both in their magnitude (1.35 degrees C) and rapidity (8-15 min). The reduction in T-re occurred even while heat loss to the environment was prevented by continued controlled warming of the water that kept T-w slightly above T-sk and while metabolic heat production alone should have added 1.6-2 degrees C/h to the T-c. This reduction in T-c could only be due to a massive redistribution of heat from the core to the blubber layer. C1 Biodivers Res & Applicat Assoc, San Diego, CA 92192 USA. USN, Command Control & Oceans Surveillance Ctr, Biosci Div, San Diego, CA 92152 USA. RP Heath, ME (reprint author), Biodivers Res & Applicat Assoc, POB 22683, San Diego, CA 92192 USA. EM MEHeath@compuserve.com NR 24 TC 5 Z9 5 U1 3 U2 6 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0363-6119 J9 AM J PHYSIOL-REG I JI Am. J. Physiol.-Regul. Integr. Comp. Physiol. PD APR PY 1999 VL 276 IS 4 BP R1188 EP R1194 PG 7 WC Physiology SC Physiology GA 183HR UT WOS:000079548600035 PM 10198402 ER PT J AU Shaffer, RE Rose-Pehrsson, SL McGill, RA AF Shaffer, RE Rose-Pehrsson, SL McGill, RA TI A comparison study of chemical sensor array pattern recognition algorithms SO ANALYTICA CHIMICA ACTA LA English DT Article DE learning vector quantization; probabilistic neural networks; pattern recognition; chemical sensors; electronic nose; artificial intelligence ID PROBABILISTIC NEURAL NETWORKS; IDENTIFICATION; CLASSIFICATION; DISCRIMINATION; SPECTRA; VAPORS AB Probabilistic neural networks (PNN), learning vector quantization (LVQ) neural networks, back-propagation artificial neural networks (BP-ANN), soft independent modeling of class analogy (SIMCA), Bayesian linear discriminant analysis (BLDA), Mahalanobis linear discriminant analysis (MLDA), and the nearest-neighbor (NN) pattern recognition algorithms are compared for their ability to classify chemical sensor array data, comparisons are made based on five qualitative criteria (speed, training difficulty, memory requirements, robustness to outliers, and the ability to produce a measure of uncertainty) and one quantitative criterion (classification accuracy). Four sample data sets from our laboratory, involving simulated data and polymer-coated surface acoustic wave chemical sensor array data, are used to estimate classification accuracies for each method. Among the seven algorithms in this study and the four data sets, the neural network based algorithms (LVQ, PNN, and BP-ANN) have the highest classification accuracies. When considering the qualitative criteria, the LVQ and PNN approaches fare well compared to BP-ANN due to their simpler training methods. The PNN is recommended for applications where a confidence measure and fast training are critical, while speed and memory requirements are not. LVQ is suggested for all other applications of chemical sensor array pattern recognition. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP Shaffer, RE (reprint author), USN, Res Lab, Div Chem, Code 6116, Washington, DC 20375 USA. RI Shaffer, Ronald/I-2134-2012 NR 34 TC 111 Z9 118 U1 3 U2 20 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0003-2670 J9 ANAL CHIM ACTA JI Anal. Chim. Acta PD APR 1 PY 1999 VL 384 IS 3 BP 305 EP 317 DI 10.1016/S0003-2670(98)00780-6 PG 13 WC Chemistry, Analytical SC Chemistry GA 178WM UT WOS:000079292200006 ER PT J AU Hannon, TJ Pekarske, WJ Polston, GR Carnevali, W Wall, N Leivers, D AF Hannon, TJ Pekarske, WJ Polston, GR Carnevali, W Wall, N Leivers, D TI Determination of platelet yields from platelet rich plasma for five autotransfusion machines SO ANESTHESIA AND ANALGESIA LA English DT Meeting Abstract C1 USN, Med Ctr, Dept Anesthesiol, San Diego, CA 92134 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0003-2999 J9 ANESTH ANALG JI Anesth. Analg. PD APR PY 1999 VL 88 IS 4 SU S BP U109 EP U109 PG 1 WC Anesthesiology SC Anesthesiology GA 185GH UT WOS:000079659400105 ER PT J AU Hannon, TJ Pekarske, WJ Polston, GR Carnevali, W Wall, NM Leivers, D AF Hannon, TJ Pekarske, WJ Polston, GR Carnevali, W Wall, NM Leivers, D TI Determination of wash quality of simulated wound salvaged blood with six autotransfusion machines SO ANESTHESIA AND ANALGESIA LA English DT Meeting Abstract C1 USN, Med Ctr, Dept Anesthesiol, San Diego, CA 92134 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0003-2999 J9 ANESTH ANALG JI Anesth. Analg. PD APR PY 1999 VL 88 IS 4 SU S BP U26 EP U26 PG 1 WC Anesthesiology SC Anesthesiology GA 185GH UT WOS:000079659400022 ER PT J AU Seely, JF Watanabe, T Harada, T Rife, JC Hunter, WR AF Seely, JF Watanabe, T Harada, T Rife, JC Hunter, WR TI Normal-incidence efficiencies of 4800-grooves/mm-ruled replica gratings with multilayer and gold coatings in the 125-325-angstrom wavelength region SO APPLIED OPTICS LA English DT Article ID X-RAY AB The normal-incidence efficiencies of two 4800-grooves/mm ruled replica gratings, one with a dual-bandpass molybdenum/silicon multilayer coating and the other with a gold coating, were measured by use of synchrotron radiation in the 125-325-Angstrom wavelength region. The peak reflectance of the multilayer coating was 22% in the first Bragg order near 235 Angstrom and 28% in the second Bragg order near 126 Angstrom. The peak efficiency of the multilayer grating was 2.6% in the first diffraction order near 225 Angstrom and 0.3% in the second diffraction order near 125 Angstrom. The efficiencies of the multilayer grating were much higher than the corresponding efficiencies of the gold grating. The characterization of the surfaces of the gratings by atomic force microscopy indicated rms microroughness values in the 5-18-mu m(-1) frequency range of 12-20 Angstrom for the multilayer grating and 22-32 Angstrom for the gold grating. Both gratings had bumpy surface features larger than the nominal groove height. The rather large surface roughness and groove irregularities had a detrimental effect on the grating efficiencies. (C) 1999 Optical Society of America. C1 USN, Res Lab, Washington, DC 20375 USA. Natl Astron Observ, Tokyo 181, Japan. Tokyo Metropolitan Univ, Hachioji, Tokyo 19203, Japan. SFA Inc, Landover, MD 20785 USA. RP Seely, JF (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM john.seely@nrl.navy.mil NR 11 TC 2 Z9 2 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD APR 1 PY 1999 VL 38 IS 10 BP 1920 EP 1925 DI 10.1364/AO.38.001920 PG 6 WC Optics SC Optics GA 184TU UT WOS:000079630200003 PM 18319746 ER PT J AU McCafferty, E Wightman, JP AF McCafferty, E Wightman, JP TI An X-ray photoelectron spectroscopy sputter profile study of the native air-formed oxide film on titanium SO APPLIED SURFACE SCIENCE LA English DT Article DE XPS; oxide film; titanium ID ION-BOMBARDMENT; SURFACE CHARACTERIZATION; TIO2; XPS; OXIDATION; REOXIDATION; ELECTRODES; REDUCTION; TIO2(001); DEFECTS AB The incipient air-formed oxide film on titanium is approximately 80 Angstrom in thickness and consists of TiO2, Sputtering the oxide film in vacuum with 3 keV argon ions changes the composition of the oxide film. XPS depth profiles obtained by sputtering with 3 keV argon ions show that after sputtering, the outermost portion of the film consists of TiO2, and that the inner portion consists of Ti2O3 and TiO. Mathematical analysis of the sputtered oxide film as a three-layer structure shows that with increased time of sputtering, the calculated thickness of TiO2 and its mole fraction in the oxide film decreases faster than that due solely to thinning of the outermost layer, In addition, the mole fraction of the TiO layer increases, while that of the Ti2O3 remains relatively unchanged during sputtering. These observations suggest that the ion beam reduces part of the TiO2 layer to Ti2O3, which in rum is then reduced to TiO. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Div Mat, Washington, DC 20375 USA. Virginia Polytech Inst & State Univ, Dept Chem, Ctr Adhes & Sealant Sci, Blacksburg, VA 24061 USA. RP McCafferty, E (reprint author), USN, Res Lab, Div Mat, Washington, DC 20375 USA. NR 29 TC 154 Z9 157 U1 11 U2 53 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 APR PY 1999 VL 143 IS 1-4 BP 92 EP 100 DI 10.1016/S0169-4332(98)00927-1 PG 9 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 192JB UT WOS:000080074200013 ER PT J AU Yater, JE Shih, A AF Yater, JE Shih, A TI Interpretation of low-energy feature in energy spectra measured from surfaces with low or negative electron affinity SO APPLIED SURFACE SCIENCE LA English DT Article DE secondary electron emission spectroscopy; NEA; wide bandgap; diamond ID EMISSION PROPERTIES; DIAMOND; TRANSPORT; NITRIDE AB The secondary electron distribution generated in wide bandgap material, such as diamond, is dominated by a high concentration of very low-energy electrons. Previous work has used the appearance of a low-energy feature in measured energy spectra to establish the presence of a negative electron affinity (NEA) at the emitting surface. In this letter, secondary electron emission spectroscopy is used to study the energy distribution of secondary electrons emitted from semiconductor surfaces having different electron affinities. We conclusively show that the emitted electron distribution depends strongly on the position of the vacuum level relative to the internal electron distribution. In fact, a low-energy peak is observed in energy spectra measured at GaN, diamond, and Si surfaces having a small but positive electron affinity. and the intensity and width of the peak increase steadily as the electron affinity decreases. Consequently, a low-energy structure in measured energy spectra is not sufficient evidence of a NEA. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Washington, DC 20375 USA. RP Yater, JE (reprint author), USN, Res Lab, Code 6844, Washington, DC 20375 USA. NR 14 TC 7 Z9 7 U1 0 U2 3 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 APR PY 1999 VL 143 IS 1-4 BP 219 EP 222 DI 10.1016/S0169-4332(98)00917-9 PG 4 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 192JB UT WOS:000080074200028 ER PT J AU Ross, EV McKinlay, JR Anderson, RR AF Ross, EV McKinlay, JR Anderson, RR TI Why does carbon dioxide resurfacing work? A Review SO ARCHIVES OF DERMATOLOGY LA English DT Review ID DIFFERENTIAL SCANNING CALORIMETRY; CO2-LASER TISSUE ABLATION; RESIDUAL THERMAL-DAMAGE; YAG LASER ABLATION; HIGH-ENERGY; PULSED CO2-LASER; ER-YAG; COLLAGEN DENATURATION; BIOLOGICAL TISSUES; ACNE SCARS AB Despite the unquestionable efficacy of carbon dioxide laser skin resurfacing, mechanisms for cosmetic enhancement remain poorly characterized. Histological studies have provided some insight into the cascade of events from initial laser impact to final skin rejuvenation. However, there are few comprehensive studies of gross and microscopic wound healing. Additionally, the literature is fragmented; excellent individual articles appear in journals from widely disparate disciplines. For example, some reports relevant to laser skin resurfacing are "sequestered" in the engineering literature. This article is intended to update the physician on laser skin resurfacing based on the broadest review of the current literature. It proceeds from a discussion of initial laser-tissue interactions, such as collagen denaturation, to examination of longterm biological sequlae. At some cost tp scientific rigor, mathematical models describing laser-tissue interactions are not presented. C1 USN, Med Ctr, Dept Dermatol, San Diego, CA 92152 USA. Massachusetts Gen Hosp, Wellman Labs Photomed, Boston, MA 02114 USA. RP Ross, EV (reprint author), USN, Med Ctr, Dept Clin Res, San Diego, CA 92134 USA. NR 97 TC 88 Z9 89 U1 0 U2 3 PU AMER MEDICAL ASSOC PI CHICAGO PA 515 N STATE ST, CHICAGO, IL 60610 USA SN 0003-987X J9 ARCH DERMATOL JI Arch. Dermatol. PD APR PY 1999 VL 135 IS 4 BP 444 EP 454 DI 10.1001/archderm.135.4.444 PG 11 WC Dermatology SC Dermatology GA 185MD UT WOS:000079672000011 PM 10206052 ER PT J AU Wheeler, DS AF Wheeler, DS TI Radiological case of the month - Transient acute renal failure of the newborn SO ARCHIVES OF PEDIATRICS & ADOLESCENT MEDICINE LA English DT Article ID CHILDREN; KIDNEYS C1 USN Hosp, Dept Pediat, FPO, AP 96538 USA. RP Wheeler, DS (reprint author), USN Hosp, Dept Pediat, PSC 490,Box 221, FPO, AP 96538 USA. EM ewheeler@gam10.med.navy.mil NR 11 TC 1 Z9 1 U1 0 U2 0 PU AMER MEDICAL ASSOC PI CHICAGO PA 515 N STATE ST, CHICAGO, IL 60610 USA SN 1072-4710 J9 ARCH PEDIAT ADOL MED JI Arch. Pediatr. Adolesc. Med. PD APR PY 1999 VL 153 IS 4 BP 423 EP 424 PG 2 WC Pediatrics SC Pediatrics GA 184TN UT WOS:000079629700016 PM 10201728 ER PT J AU Mason, BD Martin, C Hartkopf, WI Barry, DJ Germain, ME Douglass, GG Worley, CE Wycoff, GL ten Brummelaar, T Franz, OG AF Mason, BD Martin, C Hartkopf, WI Barry, DJ Germain, ME Douglass, GG Worley, CE Wycoff, GL ten Brummelaar, T Franz, OG TI Speckle interferometry of new and problem Hipparcos binaries SO ASTRONOMICAL JOURNAL LA English DT Article DE binaries : close; techniques : interferometric ID PEAK 4-M TELESCOPE; DOUBLE STARS; LUNAR OCCULTATIONS; PHOTOELECTRIC OBSERVATIONS; ORBITAL ELEMENTS; BRIGHT STARS; DUPLICITY; SYSTEMS; CATALOG; PAIRS AB The ESA Hipparcos satellite made measurements of over 12,000 double stars and discovered 3406 new systems. In addition to these, 4706 entries in the Hipparcos Catalogue correspond to double star solutions that did not provide the classical parameters of separation and position angle (rho, theta) but were the so-called problem stars, flagged "G," "O," "V," or "X" (field H59 of the main catalog). An additional subset of 6981 entries were treated as single objects but classified by Hipparcos as "suspected nonsingle" (flag "S" in held H61), thus yielding a total of 11,687 "problem stars." Of the many ground-based techniques for the study of double stars, probably the one with the greatest potential for exploration of these new and problem Hipparcos binaries is speckle interferometry. Results are presented from an inspection of 848 new and problem Hipparcos binaries, using both archival and new speckle observations obtained with the USNO and CHARA speckle cameras. C1 USN Observ, Washington, DC 20392 USA. Georgia State Univ, Ctr High Angular Resolut Astron, Atlanta, GA 30303 USA. USN Observ, Washington, DC 20392 USA. Lowell Observ, Flagstaff, AZ 86001 USA. RP Mason, BD (reprint author), Univ Texas, McDonald Obser, Austin, TX 78712 USA. NR 68 TC 66 Z9 68 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD APR PY 1999 VL 117 IS 4 BP 1890 EP 1904 DI 10.1086/300823 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 194ZK UT WOS:000080224500022 ER PT J AU Germain, ME Douglass, GG Worley, CE AF Germain, ME Douglass, GG Worley, CE TI Speckle interferometry at the USNaval Observatory. II. SO ASTRONOMICAL JOURNAL LA English DT Article DE binaries : general; binaries : visual; techniques : interferometric ID BINARY STARS; TELESCOPE AB Position angles and separations resulting from 2406 speckle interferometric observations of 547 binary stars are tabulated. This is the second in a series of papers presenting measures obtained using the 66 cm refractor at the US Naval Observatory in Washington, DC, with an intensified CCD detector. Program stars range in separation from 0." 2 to 3." 8, with Delta m less than or equal to 2.5 mag and a limiting magnitude of V = 10.0. The observation epochs run from 1993 January through 1995 August. Random errors are estimated to be 14 mas in separation and 0.degrees 52/rho in position angle, where rho is the separation in arcseconds. The instrumentation and calibration are briefly described. Aspects of the data analysis related to the avoidance of systematic errors are also discussed. C1 USN Observ, NPOI Anderson Mesa, Flagstaff, AZ 86001 USA. USN Observ, Washington, DC 20392 USA. RP Germain, ME (reprint author), USN Observ, NPOI Anderson Mesa, Flagstaff, AZ 86001 USA. NR 10 TC 15 Z9 15 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD APR PY 1999 VL 117 IS 4 BP 1905 EP 1920 DI 10.1086/300821 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 194ZK UT WOS:000080224500023 ER PT J AU Chiang, J AF Chiang, J TI Time-integrated gamma-ray burst synchrotron spectra from blast-wave/cloud interactions SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; radiation mechanisms : nonthermal; shock waves ID TEMPORAL STRUCTURE; VARIABILITY; TIMESCALES; AFTERGLOW; DURATION; REDSHIFT; ENERGY AB We show that the spectral shape of the low-energy tails found for the time-integrated spectra of gamma-ray bursts, even in the absence of strong synchrotron cooling, can be significantly softer than the nu F-nu proportional to nu(4/3) asymptote predicted by synchrotron shock models. As we have noted in a previous work, blast-wave deceleration via interaction with ambient material causes the characteristic electron injection energy to decrease in proportion to the bulk Lorentz factor of the blast wave, and under certain conditions, this effect will at least partially account for the observed increase in pulse widths with decreasing energy. This spectral softening can also be reflected in the time-integrated pulse spectrum. Using a simple model for the blast-wave interaction with a dense cloud of material, we show that just below the nu F-nu spectral peak the integrated spectrum behaves as nu F-nu similar to nu(1/2) and rolls over to a nu(4/3) dependence at lower energies, and thus a spectral shape arises that is similar to that predicted for the spectrum of a strongly synchrotron-cooled electron population. We discuss the implications of this work in the context of models of burst light-curve variability that are based on blast-wave/cloud interactions. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RP Chiang, J (reprint author), Univ Colorado, Joint Inst Lab Astrophys, Campus Box 440, Boulder, CO 80309 USA. NR 31 TC 1 Z9 1 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 1999 VL 514 IS 2 BP 856 EP 861 DI 10.1086/306991 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 194ZQ UT WOS:000080225000027 ER PT J AU Renfrew, IA Moore, GWK Holt, TR Chang, SW Guest, P AF Renfrew, IA Moore, GWK Holt, TR Chang, SW Guest, P TI Mesoscale forecasting during a field program: Meteorological support of the Labrador Sea Deep Convection Experiment SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID NUMERICAL WEATHER-PREDICTION; REAL-TIME; OCEAN; SATELLITE; DYNAMICS AB This report discusses the design and implementation of a specialized forecasting system that was set up to support the observational component of the Labrador Sea Deep Convection Experiment. This ongoing experiment is a multidisciplinary program of observations, theory, and modeling aimed at improving our knowledge of the deep convection process in the ocean, and the air-sea interaction that forces it. The observational part of the program was centered around a cruise of the R/V Knorr during winter 1997, as well as several complementary meteorological research flights. To aid the planning of ship and aircraft operations a specially tailored mesoscale model was run over the Labrador Sea, with the model output postprocessed and transferred to a remote field base. The benefits of using a warm-start analysis cycle in the model are discussed. The utility of the forecasting system is illustrated through a description of the flight planning process for several cases. The forecasts proved to be invaluable both in ship operations and in putting the aircraft in the right place at the night time. In writing this narrative the authors hope to encourage the use of similar forecasting systems in the support of future field programs, something that is becoming increasingly possible with the rise in real-time numerical weather prediction. C1 Univ Toronto, Dept Phys, Toronto, ON, Canada. USN, Res Lab, Monterey, CA USA. USN, Postgrad Sch, Monterey, CA USA. RP Renfrew, IA (reprint author), British Antarctic Survey, High Cross,Madingley Rd, Cambridge CB3 0ET, England. RI Renfrew, Ian/E-4057-2010; Moore, Kent/D-8518-2011 OI Renfrew, Ian/0000-0001-9379-8215; Moore, Kent/0000-0002-3986-5605 NR 20 TC 23 Z9 23 U1 0 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD APR PY 1999 VL 80 IS 4 BP 605 EP 620 DI 10.1175/1520-0477(1999)080<0605:MFDAFP>2.0.CO;2 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 189FW UT WOS:000079894800001 ER PT J AU Lindsay, GA Roberts, MJ Chafin, AP Hollins, RA Merwin, LR Stenger-Smith, JD Yee, RY Zarras, P Wynne, KJ AF Lindsay, GA Roberts, MJ Chafin, AP Hollins, RA Merwin, LR Stenger-Smith, JD Yee, RY Zarras, P Wynne, KJ TI Ordered films by alternating polyelectrolyte deposition of cationic side chain and anionic main chain chromophoric polymers SO CHEMISTRY OF MATERIALS LA English DT Article ID NONLINEAR-OPTICAL FILMS; BY-LAYER DEPOSITION; POLYANION AB Using the method of aqueous solution alternating polyelectrolyte deposition (APD), second-order nonlinear optical (NLO) polymer films were prepared for the first time in which both polymers were NLO-active. Films were prepared by alternately coating a solid substrate with an NLO-active side chain polycation and an NLO-active main chain polyanion. This new polyanion was comprised of alpha-cinnamoyl chromophores in the syndioregic configuration (an "accordion" polymer). The new polycation was derived from polyepichlorohydrin that was completely substituted with new stilbazolium side chain. The films were transparent and had no texture when observed by polarized microscopy. The increase in intensity of the second harmonic (SH) signal generated in the films was quadratic with each molecular layer to 20 layers. Beyond that, the SH signal intensity saturated as more layers were added. C1 USN, China Lake, CA 93555 USA. Off Naval Res, Arlington, VA 22217 USA. RP Lindsay, GA (reprint author), USN, NAWC-WD-4T4200D,1 Adm Circle, China Lake, CA 93555 USA. NR 21 TC 22 Z9 23 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD APR PY 1999 VL 11 IS 4 BP 924 EP 929 DI 10.1021/cm980433p PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 188KN UT WOS:000079845700015 ER PT J AU Conway, B Montessori, V Rouleau, D Montaner, JSG O'Shaughnessy, MV Fransen, S Shillington, A Weislow, O Mayers, DL AF Conway, B Montessori, V Rouleau, D Montaner, JSG O'Shaughnessy, MV Fransen, S Shillington, A Weislow, O Mayers, DL TI Primary lamivudine resistance in acute/early human immunodeficiency virus infection SO CLINICAL INFECTIOUS DISEASES LA English DT Article; Proceedings Paper CT 6th Annual Canadian Conference on HIV/AIDS Research CY MAY, 1997 CL OTTAWA, CANADA ID ZIDOVUDINE; TYPE-1; TRANSMISSION; NEVIRAPINE C1 Univ British Columbia, Vancouver, BC V5Z 1M9, Canada. USN, Med Res Inst, Bethesda, MD USA. SRA Technol Inc, HIV Clin Res Unit, Bethesda, MD USA. RP Conway, B (reprint author), 1134 Burrard St, Vancouver, BC, Canada. NR 5 TC 12 Z9 12 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 1058-4838 J9 CLIN INFECT DIS JI Clin. Infect. Dis. PD APR PY 1999 VL 28 IS 4 BP 910 EP 911 DI 10.1086/515225 PG 2 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA 184KP UT WOS:000079611600040 PM 10825060 ER PT J AU Blivin, SJ Martire, JR McFarland, EG AF Blivin, SJ Martire, JR McFarland, EG TI Bilateral midfibular stress fractures in a collegiate football player SO CLINICAL JOURNAL OF SPORT MEDICINE LA English DT Article C1 USN Hosp, Dept Family Practice, Jacksonville, FL USA. Union Mem Hosp, Dept Nucl Med, Baltimore, MD USA. Ctr Sports Med, Baltimore, MD USA. Johns Hopkins Univ, Sch Med, Dept Radiol, Baltimore, MD 21205 USA. Johns Hopkins Univ, Sch Med, Dept Orthoped Surg, Div Sports Med, Baltimore, MD 21205 USA. RP Blivin, SJ (reprint author), USN Hosp, Dept Family Practice, Jacksonville, FL USA. NR 10 TC 4 Z9 4 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1050-642X J9 CLIN J SPORT MED JI Clin. J. Sport Med. PD APR PY 1999 VL 9 IS 2 BP 95 EP 97 DI 10.1097/00042752-199904000-00010 PG 3 WC Orthopedics; Physiology; Sport Sciences SC Orthopedics; Physiology; Sport Sciences GA 216PV UT WOS:000081451800010 PM 10442625 ER PT J AU Mahoney, FJ AF Mahoney, FJ TI Update on diagnosis, management, and prevention of hepatitis B virus infection SO CLINICAL MICROBIOLOGY REVIEWS LA English DT Review ID LONG-TERM IMMUNOGENICITY; ANTIGEN-POSITIVE MOTHERS; PLACEBO-CONTROLLED TRIAL; CHRONIC VIRAL-HEPATITIS; PLASMA-DERIVED VACCINE; HEALTH-CARE WORKERS; SURFACE-ANTIGEN; HEPATOCELLULAR-CARCINOMA; UNITED-STATES; INFANTS BORN AB Acute and chronic hepatitis B virus (HBV) infection is a leading cause of liver disease worldwide. It is estimated that approximately 350 million people worldwide have chronic HBV infection and that 1 million persons die each year from HBV-related chronic liver disease. In the past decade, significant progress in the understanding of the molecular virology and pathogenesis of HBV infection has been made. In addition, effective treatment modalities have been developed for persons with chronic infection. Worldwide, prevention of HBV transmission has become a high priority. In 1992, the Global Advisory Group to the World Health Organization recommended that all countries integrate hepatitis B vaccine into national immunization programs by 1997. Currently, 80 countries have done so and several others are planning to. Many countries have reported dramatic reductions in the prevalence of chronic HBV infection among children born since the hepatitis B vaccine was introduced into infant immunization schedules. Recent reports from Taiwan indicate a reduction in the incidence of liver cancer among children as a result of widespread hepatitis B vaccination programs. C1 USN, Off Director, Natl Ctr Infect Dis, Ctr Dis Control & Prevent,Med Res Unit 3, Cairo, Egypt. RP Mahoney, FJ (reprint author), USN, Med Res Unit 3, PSC 452,Box 146, FPO, AE 09835 USA. EM MahoneyF@namru3.navy.mil NR 167 TC 212 Z9 230 U1 1 U2 5 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0893-8512 J9 CLIN MICROBIOL REV JI Clin. Microbiol. Rev. PD APR PY 1999 VL 12 IS 2 BP 351 EP + PG 17 WC Microbiology SC Microbiology GA 186DU UT WOS:000079712600009 PM 10194463 ER PT J AU Cilento, BG Holmes, NM Canning, DA AF Cilento, BG Holmes, NM Canning, DA TI Plastibell (R) complications revisited SO CLINICAL PEDIATRICS LA English DT Article ID CIRCUMCISION; DEVICE C1 USN, Ctr Med, Dept Urol, San Diego, CA 92152 USA. RP Cilento, BG (reprint author), Childrens Hosp, Dept Urol, 300 Longwood Ave, Boston, MA 02115 USA. NR 12 TC 6 Z9 6 U1 0 U2 0 PU WESTMINSTER PUBL INC PI GLEN HEAD PA 708 GLEN COVE AVE, GLEN HEAD, NY 11545 USA SN 0009-9228 J9 CLIN PEDIATR JI Clin. Pediatr. PD APR PY 1999 VL 38 IS 4 BP 239 EP 242 DI 10.1177/000992289903800406 PG 4 WC Pediatrics SC Pediatrics GA 187QK UT WOS:000079798100006 PM 10326180 ER PT J AU Khokhlov, AM Oran, ES Chtchelkanova, AY Wheeler, JC AF Khokhlov, AM Oran, ES Chtchelkanova, AY Wheeler, JC TI Interaction of a shock with a sinusoidally perturbed flame SO COMBUSTION AND FLAME LA English DT Article ID PROPAGATION AB The interaction of a shock wave and a sinusoidally perturbed premixed flame was studied by solving the reactive Navier-Stokes equations with flame front resolved. An idealized chemical model was used that reproduces the combustion properties of a stoichiometric acetylene-air mixture. The interaction increases the surface area of the flame and the energy release in the system. The increase in energy release is due to two effects: the increase in surface area and the increase in the density of the compressed material. The timescale of the growth of the energy release is the Richtmyer-Meshkov characteristic timescale. The interaction creates vorticity, and the vortices act to maintain a high level of energy release long after the shock wave has passed through the flame. The strength of this vorticity is not enough to stretch and locally extinguish the flame. Three-dimensional perturbations of the same amplitude and wavelength grow a factor of similar or equal to 2 faster than the two-dimensional perturbations, and the maximum energy release rate is a factor of similar or equal to 2 larger. The calculations show that the maximum increase in the energy generation rate due to a single interaction of a shock and a flame does not exceed a factor of 20 to 30. To greatly increase the burning rate, multiple shock-flame interactions are required. (C) 1998 by The Combustion Institute. C1 USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. Berkeley Res Associates Inc, Berkeley, CA USA. Univ Texas, Dept Astron, Austin, TX 78712 USA. RP Khokhlov, AM (reprint author), USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. EM ajk@lcp.nrl.navy.mil NR 37 TC 55 Z9 66 U1 0 U2 6 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD APR PY 1999 VL 117 IS 1-2 BP 99 EP 116 DI 10.1016/S0010-2180(98)00090-X PG 18 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 162UX UT WOS:000078366200006 ER PT J AU Khokhlov, AM Oran, ES Thomas, GO AF Khokhlov, AM Oran, ES Thomas, GO TI Numerical simulation of deflagration-to-detonation transition: The role of shock-flame interactions in turbulent flames SO COMBUSTION AND FLAME LA English DT Article ID LAMINAR AB Two-dimensional reactive Navier-Stokes equations for an acetylene-air mixture are solved numerically to simulate the interaction of a shock wave and an expanding flame front, the formation of a flame brush, and deflagration-to-detonation transition (DDT). The effects of viscosity, thermal conduction, molecular diffusion, and chemical reactions are included. A new method for adaptive mesh refinement was used to ensure that the structure of the flame front was resolved. The shock-flame interactions, through the Richtmyer-Meshkov instability, create and maintain a highly turbulent flame brush. The turbulence is not Kolmogorov turbulence, but it is driven at all scales by repeated shock-flame interactions. Pressure fluctuations generated in the region of the turbulent flame brush create, in turn, hot spots in unreacted material. These hot spots may then transition to DDT through the gradient mechanism. Repeated shock-flame interactions and merging shocks in unreacted material lead to the development of a high-speed shock that moves out in front of the turbulent flame. The region between this shock and the flame is subject to intense fluctuations generated in the flame. The simulations show that the interactions of shocks and flames create the conditions under which deflagration-to-detonation transition may occur. (C) 1999 by The Combustion Institute. C1 USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. Univ Wales, Dept Phys, Aberystwyth, Dyfed, Wales. RP Khokhlov, AM (reprint author), USN, Res Lab, Computat Phys & Fluid Dynam Lab, Code 6404, Washington, DC 20375 USA. NR 22 TC 104 Z9 129 U1 0 U2 32 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD APR PY 1999 VL 117 IS 1-2 BP 323 EP 339 DI 10.1016/S0010-2180(98)00076-5 PG 17 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 162UX UT WOS:000078366200019 ER PT J AU Bucher, P Yetter, RA Dryer, FL Vicenzi, EP Parr, TP Hanson-Parr, DM AF Bucher, P Yetter, RA Dryer, FL Vicenzi, EP Parr, TP Hanson-Parr, DM TI Condensed-phase species distributions about Al particles reacting in various oxidizers SO COMBUSTION AND FLAME LA English DT Article ID COMBUSTION AB Experimental results on the combustion of single, isolated aluminum particles, laser ignited in quiescent environments consisting of pure N2O, CO2, CO and in mixtures of 21% O-2 / 79% N-2 and 21% O-2 / 79% Ar are reported. Combustion measurements consisted of photographic observations and electron probe microanalysis (EPMA) of the condensed-phase product composition and radial distribution. Aluminum particles in O-2, CO2, and N2O atmospheres were found to burn with envelope flames. Of these oxidizers, the largest flame envelope, as determined by the condensed-product distribution, occurred for Al combustion in the O-2/Ar mixture, followed by Al combustion in the O-2/N-2 mixture, the CO2 atmosphere, and the N2O atmosphere. Combustion in the CO atmosphere appeared to occur on (near) the particle surface with only a weak envelope reaction. Consistent with previous results in the literature, Al particle disruption was not observed in O-2/Ar environments, but was observed in O-2/N-2 environments. Although speculated in the literature, the present work confirms the existence of aluminum nitrides (oxy-nitrides) in the fuel-rich region near the particle surface for nitrogen-containing oxidizers (i.e., O-2/N-2 and N2O). Equilibrium calculations indicate that near the surface, solid-phase AlN may exist to temperatures well above the melting temperature of aluminum oxide. Thus, its presence may affect the fragmentation process. Finally, condensed-phase carbon (possibly in the form of aluminum carbide) was found throughout the surrounding gas-phase for CO combustion. (C) 1999 by The Combustion Institute. C1 Princeton Univ, Princeton, NJ 08544 USA. USN, Air Warfare Ctr, Weap Div, China Lake, CA 93555 USA. RP Dryer, FL (reprint author), Princeton Univ, Princeton, NJ 08544 USA. EM fldryer@phoenix.princeton.edu NR 17 TC 43 Z9 43 U1 1 U2 9 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD APR PY 1999 VL 117 IS 1-2 BP 351 EP 361 DI 10.1016/S0010-2180(98)00074-1 PG 11 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 162UX UT WOS:000078366200021 ER PT J AU Ross, EV Ladin, Z Kreindel, M Dierickx, C AF Ross, EV Ladin, Z Kreindel, M Dierickx, C TI Theoretical considerations in laser hair removal SO DERMATOLOGIC CLINICS LA English DT Article ID FOLLICULAR STEM-CELLS; PORT-WINE STAINS; SELECTIVE PHOTOTHERMOLYSIS; IRRADIATED TISSUE; TIME CONSTANTS; RUBY-LASER; BULGE AREA; RED HAIR; MODEL; SKIN AB A systematic and logical approach fur laser hair removal demands an understanding of its biologic and physical bases. This article presents an overview of hair anatomy and physiology followed by a mathematically nonrigorous review of tissue optics and thermal responses to laser irradiation. The reader is provided with a step by step approach to laser hair removal. C1 USN, Ctr Med, Div Dermatol, San Diego, CA 92134 USA. RP Ross, EV (reprint author), USN, Ctr Med, Div Dermatol, San Diego, CA 92134 USA. NR 77 TC 72 Z9 73 U1 0 U2 4 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0733-8635 J9 DERMATOL CLIN JI Dermatol. Clin. PD APR PY 1999 VL 17 IS 2 BP 333 EP + DI 10.1016/S0733-8635(05)70091-7 PG 25 WC Dermatology SC Dermatology GA 192GJ UT WOS:000080069900014 PM 10327301 ER PT J AU McDaniel, DH Lord, J Ash, K Newman, J AF McDaniel, DH Lord, J Ash, K Newman, J TI Combined CO2/Erbium : YAG laser resurfacing of peri-oral rhytides and side-by-side comparison with carbon dioxide laser alone SO DERMATOLOGIC SURGERY LA English DT Article; Proceedings Paper CT 18th Annual Meeting of the American-Society-for-Laser-Medicine-and-Surgery CY APR 06, 1998 CL SAN DIEGO, CALIFORNIA SP Amer Soc Laser Med & Surg ID ERBIUM-YAG LASER; HIGH-ENERGY; TOPICAL TRETINOIN; FACIAL SKIN; ABLATION; ERYTHEMA; SURGERY; DAMAGE; TERM AB BACKGROUND. Laser resurfacing of facial rhytids has become a popular treatment option for many patients with wrinkles, photoaging, and acne scarring. Laser wavelength options and optimization of techniques continue to evolve in an attempt to shorten the healing phase associated with laser skin resurfacing. OBJECTIVE. TO prospectively study the clinical effects of pulsed carbon dioxide (CO2) laser resurfacing of facial rhytids used alone, compared with a combination of CO2 and the pulsed Erbium:YAG (Er:YAG) laser. METHODS. Forty treatment sites on 20 patients were randomized and evaluated following treatment of the upper lip region with a combination of CO, laser resurfacing alone or with the same CO? laser treatment followed by 3 passes with the Er: YAG laser. Patient diaries were maintained to assess erythema, crusting, pain, itching, swelling, pigmentary changes, and the day of first make-up application. Blinded objective grading of improvement was independently assessed by 4 blinded observers at time intervals 3, 6, and 10 days, and 1, 2, and 4 months. Chromometer measurements of erythema were also analyzed and percentage moisture recorded. RESULTS. Subjectively, all patients reported, on average, ence noted between the two procedures. On average, patients were able to apply make-up 5.5 days postoperatively, regardless of which procedure used. However, the combined CO2/Er:YAG laser treatment patients experienced reduced duration of crusting, compared to the patients treated with CO2 alone. The duration of crusting was reduced on average from 7.4 to 6.5 days, and also the duration of itching was reduced in patients receiving combined treatment from 5.5 to 4.8 days. Chromometer measurements noted no significant difference between techniques in the rate of resolution of erythema. Blinded objective grading revealed that crusting was reduced on average from 7.2 to 6.0 days, and swelling was reduced from 6.3 to 6.0 days in patients receiving the combined procedure. No cases of permanent hyperpigmentation, hypopigmentation, or scarring occurred in any patients. CONCLUSION. The addition of the Er:YAG laser following CO2 laser resurfacing reduces the duration of crusting, swelling, and itching postoperatively. Medium to deep (Grade III) facial rhytids were improved by 70% with both procedures with no significant difference noted between techniques. C1 Laser Ctr Virginia, Virginia Beach, VA 23454 USA. Eastern Virginia Med Sch, Norfolk, VA 23501 USA. USN, Med Ctr Portsmouth, Dept Gen Surg, Portsmouth, VA USA. RP McDaniel, DH (reprint author), Laser Ctr Virginia, 933 1st Colonial Rd,Suite 113, Virginia Beach, VA 23454 USA. NR 38 TC 28 Z9 28 U1 0 U2 1 PU BLACKWELL SCIENCE INC PI MALDEN PA 350 MAIN ST, MALDEN, MA 02148 USA SN 1076-0512 J9 DERMATOL SURG JI Dermatol. Surg. PD APR PY 1999 VL 25 IS 4 BP 285 EP 293 DI 10.1046/j.1524-4725.1999.08162.x PG 9 WC Dermatology; Surgery SC Dermatology; Surgery GA 188LK UT WOS:000079848300011 PM 10417584 ER PT J AU Flower, R Rudolph, AS AF Flower, R Rudolph, AS TI Effects of free and liposome-encapsulated hemoglobin on choroidal vascular plexus blood flow, using the rabbit eye as a model system SO EUROPEAN JOURNAL OF OPHTHALMOLOGY LA English DT Article DE hemoglobin; vascular plexus; choroid; hemodynamics; blood ID STROMA-FREE HEMOGLOBIN; ENDOTHELIAL-CELLS; OXYGEN; RELAXATION; RAT; ACETYLCHOLINE; MICROSCOPY; ARTERIOLES; PANCREAS; PRESSURE AB Purpose. This study investigated the vasoconstrictive effects of both stroma-free and liposome-encapsulated cross-linked hemoglobin (Hb) on vascular plexus hemodynamics, using the choroid of the rabbit eye as a model system. Methods. Sequential subfraction of high-speed ICG fluorescence angiogram images facilitated visualization of the time-varying patterns of blood flow distribution in the choriocapillaris during the cardiac cycle. Differences between baseline and post-hemoglobin injection blood flow distributions were analyzed. Likewise, differences in the time-varying patterns of flow distribution between the particulate and liquid phases of blood during a cardiac cycle were investigated, since this may bear on differences in vasoactivity induced by circulating stroma-free vs. encapsulated Hb. Results. Cross-linked Hb induced a transient, but marked, localized reduction in choriocapillaris blood flow. This effect was significantly attenuated when liposome encapsulated cross-linked hemoglobin was administered. Plexus blood flow distribution was different for particulate and liquid ICG. Conclusions. Differences in particulate and liquid ICG flow patterns suggest that one contribution to the different plexus blood flow patterns observed in the encapsulated and free Hb experiments may be due to differences in liquid and particle-bound Hb distribution within the plexus. The observed choriocapillaris blood flow reductions may be attributable to an aggregate endothelial cell contractility induced by presence of extra-cellular Hb in the choriocapillaris plexus. C1 Univ Maryland, Sch Med, Dept Ophthalmol, Baltimore, MD 21201 USA. USN, Lab Ctr BioMol Sci & Engn, Washington, DC USA. RP Flower, R (reprint author), 11 Dellwood Court, Hunt Valley, MD 21030 USA. NR 35 TC 0 Z9 0 U1 0 U2 0 PU WICHTIG EDITORE PI MILAN PA 72/74 VIA FRIULI, 20135 MILAN, ITALY SN 1120-6721 J9 EUR J OPHTHALMOL JI Eur. J. Ophthalmol. PD APR-JUN PY 1999 VL 9 IS 2 BP 103 EP 114 PG 12 WC Ophthalmology SC Ophthalmology GA 212XM UT WOS:000081243000006 PM 10435422 ER PT J AU Coyle, WJ Delaney, N Yoshihashi, A Lawson, P AF Coyle, WJ Delaney, N Yoshihashi, A Lawson, P TI Metformin treatment in patients with nonalcoholic steatohepatitis normalizes LFTs and improves histology SO GASTROENTEROLOGY LA English DT Meeting Abstract C1 USN, Med Ctr, Portsmouth, VA USA. NR 0 TC 6 Z9 6 U1 0 U2 0 PU W B SAUNDERS CO-ELSEVIER INC PI PHILADELPHIA PA 1600 JOHN F KENNEDY BOULEVARD, STE 1800, PHILADELPHIA, PA 19103-2899 USA SN 0016-5085 J9 GASTROENTEROLOGY JI Gastroenterology PD APR PY 1999 VL 116 IS 4 MA L0083 BP A1198 EP A1199 PN 2 PG 2 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA 187GJ UT WOS:000079778405192 ER PT J AU Schafer, TW Brann, OS Schindler, WR AF Schafer, TW Brann, OS Schindler, WR TI Cirrhosis due to biliopancreatic diversion in an alcoholic SO GASTROENTEROLOGY LA English DT Meeting Abstract C1 USN, Med Ctr, San Diego, CA 92152 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU W B SAUNDERS CO-ELSEVIER INC PI PHILADELPHIA PA 1600 JOHN F KENNEDY BOULEVARD, STE 1800, PHILADELPHIA, PA 19103-2899 USA SN 0016-5085 J9 GASTROENTEROLOGY JI Gastroenterology PD APR PY 1999 VL 116 IS 4 MA G2525 BP A576 EP A576 PN 2 PG 1 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA 187GJ UT WOS:000079778402526 ER PT J AU Hoppel, KW Bowman, KP Bevilacqua, RM AF Hoppel, KW Bowman, KP Bevilacqua, RM TI Northern hemisphere summer ozone variability observed by POAM II SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MODEL-CALCULATIONS; HIGH-LATITUDE; POLAR OZONE; UARS MLS; STRATOSPHERE; HALOE AB Zonal asymmetry in ozone mixing ratio was observed by POAM II during the 1994-1996 summers between 55 degrees N and 65 degrees N and between 21 km aid 28 km in altitude. The zonal variance can be described as persistent large-scale ozone patterns that move approximately with the zonal mean wind. The histories of air parcels observed by FOAM are deduced from 20-day back trajectories using UKMO winds which have been corrected for stationary anomalies. The ozone mixing ratio is found to correlate with the average latitude of the back trajectory throughout the summer, indicating that the zonal variance is a result of meridional transport. The meridional transport appears to be caused by breaking of westward-propagating waves that are evanescent in the summer easterly flow. C1 USN, Res Lab, Washington, DC 20375 USA. Texas A&M Univ, Dept Meteorol, College Stn, TX 77842 USA. George Mason Univ, Inst Computat Sci & Informat, Fairfax, VA 22030 USA. RP Hoppel, KW (reprint author), USN, Res Lab, Code 7227, Washington, DC 20375 USA. RI Bowman, Kenneth/A-1345-2012 OI Bowman, Kenneth/0000-0002-2667-8632 NR 17 TC 24 Z9 24 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 1 PY 1999 VL 26 IS 7 BP 827 EP 830 DI 10.1029/1999GL900118 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 182AW UT WOS:000079477200005 ER PT J AU Livingston, ES Tolstoy, A Worcester, PF AF Livingston, ES Tolstoy, A Worcester, PF TI Special issue on long-range propagation SO IEEE JOURNAL OF OCEANIC ENGINEERING LA English DT Editorial Material ID NORMAL MODE AMPLITUDES; RANDOM OCEAN; STATISTICS C1 Off Naval Res, Arlington, VA 22217 USA. Integrated Performance Decis, Annandale, VA 22003 USA. Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. RP Livingston, ES (reprint author), Off Naval Res, Arlington, VA 22217 USA. NR 6 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 USA SN 0364-9059 J9 IEEE J OCEANIC ENG JI IEEE J. Ocean. Eng. PD APR PY 1999 VL 24 IS 2 BP 133 EP 137 DI 10.1109/JOE.1999.757266 PG 5 WC Engineering, Civil; Engineering, Ocean; Engineering, Electrical & Electronic; Oceanography SC Engineering; Oceanography GA 188VG UT WOS:000079869000001 ER PT J AU Collins, MD Lingevitch, JF AF Collins, MD Lingevitch, JF TI Secular behavior and breakdown of chaotic ray solutions SO IEEE JOURNAL OF OCEANIC ENGINEERING LA English DT Article DE caustics; long-range propagation; ray chaos; secularity; tomography; transport equation ID SEMICLASSICAL DYNAMICS; INHOMOGENEOUS-MEDIA; LONG; PROPAGATION; ACCURACY AB Solutions of the eikonal equation and the first two transport equations are derived for problems involving ray chaos. The solution of the eikonal equation approximates the phase, The solutions of the transport equations approximate the amplitude as an asymptotic series in omega(-1). Examples are presented to illustrate that the second term in the series grows relative to the first term along some rays, This secular behavior is associated with the exponential decay of amplitude, which occurs along chaotic rays. The results suggest that chaotic ray solutions (including ray paths, phases, and amplitudes) break down rapidly with range. Although the analysis is limited to a special case that is free of caustics, the results bring into question the use of chaotic ray solutions for long-range propagation. C1 USN, Res Lab, Washington, DC 20375 USA. RP Collins, MD (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 24 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 USA SN 0364-9059 J9 IEEE J OCEANIC ENG JI IEEE J. Ocean. Eng. PD APR PY 1999 VL 24 IS 2 BP 232 EP 236 DI 10.1109/48.757274 PG 5 WC Engineering, Civil; Engineering, Ocean; Engineering, Electrical & Electronic; Oceanography SC Engineering; Oceanography GA 188VG UT WOS:000079869000009 ER PT J AU Kapetanakos, CA Hafizi, B Milchberg, HM Sprangle, P Hubbard, RF Ting, A AF Kapetanakos, CA Hafizi, B Milchberg, HM Sprangle, P Hubbard, RF Ting, A TI Generation of high-average-power ultrabroad-band infrared pulses SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article DE broad-band radiation; carbon dioxide lasers; infrared radiation; nonlinearities; nonlinear media; nonlinear optics AB This paper summarizes the results of analytical and numerical studies on a novel technique that is capable of providing high average power ultra broadband radiation that extends from approximately 2 to 16 mu m, Such a spectrum has several potential applications, including telecommunications and remote sensing. Additional attractive features of the new source are its anticipated compact size, light weight, ruggedness, and affordable cost, The technique is based on the interaction of a beat wave with a nonlinear medium. The beat wave is formed from the mixing of two CO laser beams with closely spaced wavelengths, such as 9.5 and 9.6 mu m. The discrete ultrabroad-band spectrum is generated in a nonlinear optical medium by the self-phase modulation process, a third-order nonlinearity. The long-wavelength portion of the spectrum, i,e,, from 5 to 16 mu m is produced directly from the interaction of the beat wave with a GaAs crystal. The short-wavelength portion of the spectrum is produced from the interaction of a frequency doubled beat wave with a GaAs crystal following the chirping of the pulse by a different GaAs crystal and its subsequent optimal compression by a thin sapphire slab. C1 LET Corp, Washington, DC 20007 USA. Icarus Res Inc, Bethesda, MD 20824 USA. Univ Maryland, Inst Phys Sci & Technol, College Pk, MD 20742 USA. USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. RP Kapetanakos, CA (reprint author), LET Corp, Washington, DC 20007 USA. NR 15 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 USA SN 0018-9197 J9 IEEE J QUANTUM ELECT JI IEEE J. Quantum Electron. PD APR PY 1999 VL 35 IS 4 BP 565 EP 576 DI 10.1109/3.753661 PG 12 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 181CV UT WOS:000079423800018 ER PT J AU Dennis, ML Carruthers, TF Kaechele, WI Jenkins, RB Kang, JU Duling, IN AF Dennis, ML Carruthers, TF Kaechele, WI Jenkins, RB Kang, JU Duling, IN TI Long span repeaterless transmission using adiabatic solitons SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE nonlinear fiber optics; optical fiber communication; optical solitons; repeaterless transmission; solitons; stimulated Brillouin scattering ID UNREPEATERED TRANSMISSION; FIBER AB We demonstrate transmission of 10 Gb/s data over 296 km without inline amplification using adiabatically propagating optical solitons as the data carrier. Adiabatic soliton propagation suppresses the deleterious effects of self-phase modulation and stimulated Brillouin scattering, allowing higher optical powers at the transmitter. The system power budget is also enhanced by the narrowing of the optical bandwidth under adiabatic propagation, allowing improved receiver sensitivity, We show that the technique may ultimately enable repeaterless spans in excess of 500 km. C1 USN, Res Lab, Adv Lightwave Applicat Sect, Washington, DC 20375 USA. USN Acad, Dept Elect Engn, Annapolis, MD 21402 USA. RP Dennis, ML (reprint author), USN, Res Lab, Adv Lightwave Applicat Sect, Code 5654, Washington, DC 20375 USA. RI Kang, Jin/A-3228-2010 NR 12 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 USA SN 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD APR PY 1999 VL 11 IS 4 BP 478 EP 480 DI 10.1109/68.752554 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 179JE UT WOS:000079322500028 ER PT J AU Drumheller, DM AF Drumheller, DM TI Estimating matched filter amplitude probability functions by failure rate analysis SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Article ID PADE APPROXIMATIONS; STATISTICAL-MODEL; SEA CLUTTER; REVERBERATION; NOISE; FLUCTUATIONS; TARGETS; SURFACE; BOTTOM AB Performance analysis of echolocation systems requires knowledge of the probability density function (pdf) or cumulative distribution function (cdf) of a matched filter output. A method is presented to estimate these and other probability functions from data by estimating the failure rate function, a function employed in reliability theory. The method can also be used to derive approximations to closed-form probability functions. The method is demonstrated using experimental sonar and radar clutter data and a closed-form radar clutter model. C1 USN, Res Lab, Acoust Div, Washington, DC 20375 USA. RP Drumheller, DM (reprint author), USN, Res Lab, Acoust Div, Code 7140, Washington, DC 20375 USA. NR 20 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 USA SN 0018-9251 J9 IEEE T AERO ELEC SYS JI IEEE Trans. Aerosp. Electron. Syst. PD APR PY 1999 VL 35 IS 2 BP 627 EP 636 DI 10.1109/7.766943 PG 10 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 199CK UT WOS:000080461600021 ER PT J AU Blank, M Danly, BG Levush, B AF Blank, M Danly, BG Levush, B TI Experimental demonstration of a W-band (94 GHz) gyrotwystron amplifier SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article; Proceedings Paper CT International Workshop on CRMs and Gyrotrons CY MAY 18-21, 1998 CL MA ALE HACHAMISHA, ISRAEL SP Israeli Acad Sci & Humanities DE broadband millimeter wave amplifier; gyro amplifier; gyrotwystron ID HIGH-POWER OPERATION; GYROKLYSTRON AMPLIFIER; DESIGN; PERFORMANCE; GAIN AB A four section, TE01 mode W-band gyrotwystron amplifier has been designed, built, and tested. The circuit consists of three cavities followed by a traveling wave output section, each operating near the fundamental cyclotron frequency. The gyrotwystron has produced 50 kW peak output power, corresponding to 17.5% efficiency for a 57 kV, 5 A electron beam; the amplifier is zero drive stable at the operating point. The measured center frequency is 93.9 GHz with a full width half maximum instantaneous bandwidth of 925 MHz. These results represent a substantial improvement in the power-bandwidth product over previously demonstrated gyro amplifiers in this band. The small signal and saturated gains were 39 and 30 dB, respectively. The measured results are in good agreement with theoretical predictions. C1 USN, Res Lab, Washington, DC 20375 USA. RP Blank, M (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 20 TC 12 Z9 13 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD APR PY 1999 VL 27 IS 2 BP 405 EP 411 DI 10.1109/27.772267 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 211YM UT WOS:000081189500014 ER PT J AU Nusinovich, GS Levush, B Danly, BG AF Nusinovich, GS Levush, B Danly, BG TI Gain and bandwidth in stagger-tuned gyroklystrons and gyrotwystrons SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article; Proceedings Paper CT International Workshop on CRMs and Gyrotrons CY MAY 18-21, 1998 CL MA ALE HACHAMISHA, ISRAEL SP Israeli Acad Sci & Humanities DE bandwidth; gain; gyroklystrons; gyrotwystrons; stagger tuning ID LINEAR-THEORY; GYROTRON; AMPLIFIER AB This paper describes an analytical approach to consideration of the tradeoff between the gain and the bandwidth in gyroklystrons and gyrotwystrons with stagger-tuned cavities, This approach is based on the "point-gap" model, in which short cavities are responsible for electron energy modulation only, while orbital phase bunching caused by this modulation proceeds in long drift sections. The paper contains a review of results of the analysis of stagger-tuned gyroklystrons and gyrotwystrons obtained previously. It also includes new results of the study of gyroklystrons in which different cavities operate at different cyclotron harmonics. C1 Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. Omega P, New Haven, CT 06520 USA. USN, Res Lab, Washington, DC 20375 USA. RP Nusinovich, GS (reprint author), Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. NR 28 TC 6 Z9 6 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD APR PY 1999 VL 27 IS 2 BP 422 EP 428 DI 10.1109/27.772269 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 211YM UT WOS:000081189500016 ER PT J AU Therrien, CW Jenkins, WK Li, XH AF Therrien, CW Jenkins, WK Li, XH TI Optimizing the performance of polynomial adaptive filters: Making quadratic filters converge like linear filters SO IEEE TRANSACTIONS ON SIGNAL PROCESSING LA English DT Article DE adaptive; nonlinear filters; polynomial; Volterra ID SYSTEM-IDENTIFICATION; VOLTERRA AB The correlation properties of the input vector determine the rate of convergence of the LMS algorithm for Volterra adaptive filters and are optimal when the nonlinear input terms are uncorrelated. This correspondence presents new results on the correlation properties for second-order Volterra filters and shows that when the input signal is whitened, the nonlinear terms automatically become uncorrelated. C1 USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. Univ Illinois, Coordinated Sci Lab, Urbana, IL 61801 USA. RP Therrien, CW (reprint author), USN, Postgrad Sch, Dept Elect & Comp Engn, Monterey, CA 93943 USA. NR 6 TC 4 Z9 4 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1053-587X J9 IEEE T SIGNAL PROCES JI IEEE Trans. Signal Process. PD APR PY 1999 VL 47 IS 4 BP 1169 EP 1171 DI 10.1109/78.752619 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA 178QX UT WOS:000079278400029 ER PT J AU Hull, AJ AF Hull, AJ TI An inverse method to measure the breathing wave speed in a liquid-filled cylindrical shell SO INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES LA English DT Article; Proceedings Paper CT 3rd International Conference on Modern Practice in Stress and Vibration Analysis CY SEP 03-05, 1997 CL DUBLIN, IRELAND SP Univ Coll Dublin, Inst Phys, Stress & Vibrat Grp DE inverse method; breathing wave speed measurement; liquid-filled cylindrical shell; wave speed; wave propagation AB An inverse method is developed for measuring the breathing wave speed in a liquid-filled cylindrical shell. The model used with this method is based on an experimental configuration in which a long cylindrical shell is longitudinally excited by a mechanical shaker at one end. The resulting longitudinal wave propagation produces a spatial field in the shell that consists of extensional and breathing waves. End-mounted accelerometers and force transducers are used to measure the extensional wave speed. Once this is accomplished, transfer functions between five equally spaced hydrophones (in the fluid) and a forward accelerometer are recorded. These data are then combined to yield a closed-form value of the complex, frequency-dependent breathing wave speed. The experiment included to validate this method is extremely easy to implement and can be rapidly executed. (C) 1998 Elsevier Science Ltd. Ail rights reserved. C1 USN, Undersea Warfare Ctr Div, Submarine Sonar Dept, Newport, RI 02841 USA. RP Hull, AJ (reprint author), USN, Undersea Warfare Ctr Div, Submarine Sonar Dept, Newport, RI 02841 USA. NR 4 TC 0 Z9 0 U1 1 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0020-7403 J9 INT J MECH SCI JI Int. J. Mech. Sci. PD APR-MAY PY 1999 VL 41 IS 4-5 BP 373 EP 383 DI 10.1016/S0020-7403(98)00072-1 PG 11 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 144YD UT WOS:000077342700002 ER PT J AU Verma, S Jaynes, CJ AF Verma, S Jaynes, CJ TI Aircraft P-3 corrosion control issues SO JOURNAL OF ADVANCED MATERIALS LA English DT Article AB In recent years, the P-3 Aircraft Weapons System has experienced ever-increasing amounts of corrosion-related maintenance during Depot-level overhaul. The P-3 airframe being manufactured mostly from 7000 series aluminum alloys is susceptible to various types of corrosion when operating and based near marine environments. The structures of most concern are; the wing, wingbox, and empennage. Galvanic corrosion from the interaction of aluminum and stainless steel has been a problem on the nacelle and the auxiliary power unit (APU). In addition, the floor structure adjacent to the galley, lavatory and entrance and overwing exit hatches, has proven to be extremely susceptible to corrosion attack due to spillage and leakage of fluids. This paper discusses a number of actions that have been taken to improve the availability and maintainability of current aircraft and insure that the full projected service life of fleet aircraft can be attained. These actions include replacing some of the key corrosion-prone components and utilizing more applicable corrosion protection materials and processes. Particular emphasis is given to corrosion preventive compounds and a new adhesive film that has the potential to replace exterior paint topcoats. C1 USN, Air Syst Command, Patuxent River, MD 20670 USA. RP Verma, S (reprint author), USN, Air Syst Command, Patuxent River, MD 20670 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU SAMPE PUBLISHERS PI COVINA PA 1161 PARKVIEW DRIVE, COVINA, CA 91722 USA SN 1070-9789 J9 J ADV MATER JI J. Adv. Mater. PD APR PY 1999 VL 31 IS 2 BP 34 EP 40 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA 209HZ UT WOS:000081043300004 ER PT J AU Kelso, JM Mootrey, GT Tsai, TF AF Kelso, JM Mootrey, GT Tsai, TF TI Anaphylaxis from yellow fever vaccine SO JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY LA English DT Article DE allergy; anaphylaxis; yellow fever vaccine ID IMMEDIATE-TYPE REACTIONS; GELATIN; CHILDREN; MEASLES; IGE; ALLERGY AB Background: There are very few reports of anaphylactic reactions to yellow fever (YF) vaccine in the literature, and these date from the 1940s, Objective: We sought to estimate the rate of YF vaccine-related anaphylaxis, Methods: All reports of adverse reactions to YF vaccine submitted to the Vaccine Adverse Event Reporting System between 1990 and 1997 were reviewed for those meeting criteria for probable or possible anaphylactic reactions. Results: Of 243 reports submitted, 40 describe probable or possible anaphylactic reactions. In 22 of these 40, YF vaccine was the only vaccine administered. There were 5,236,820 doses of YF vaccine distributed in the United States during this period. By using all 40 Eases, the rate of YF vaccine-related anaphylaxis would be 40 in 5,236,820 or about 1 in 131,000, In 35 of the reports, information was provided on whether previous doses of YF vaccine had been given. In 34 of these 35, the reaction occurred after the first dose of YF vaccine, suggesting that vaccine constituents other than the viral proteins may have been the allergens. The vaccine is grown in chicken embryos and contains gelatin as a stabilizer. Conclusion: YP vaccine can cause anaphylactic reactions. Persons presenting for YF vaccine should be asked if they have had adverse reactions to previous doses of this or other vaccines and if they are allergic to eggs, chicken, or gelatin. Health care workers administering YF vaccine should be prepared to recognize and treat anaphylactic reactions should they occur. C1 USN, Med Ctr, Dept Internal Med, Div Allergy, San Diego, CA 92134 USA. Ctr Dis Control & Prevent, Natl Immunizat Program, Vaccine Safety & Dev Act, Atlanta, GA 30333 USA. Ctr Dis Control & Prevent, Div Vector Borne Infect Dis, Ft Collins, CO USA. RP Kelso, JM (reprint author), USN, Med Ctr, Dept Clin Res, San Diego, CA 92134 USA. NR 18 TC 70 Z9 74 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0091-6749 J9 J ALLERGY CLIN IMMUN JI J. Allergy Clin. Immunol. PD APR PY 1999 VL 103 IS 4 BP 698 EP 701 DI 10.1016/S0091-6749(99)70245-9 PG 4 WC Allergy; Immunology SC Allergy; Immunology GA 186HY UT WOS:000079723900026 PM 10200022 ER PT J AU Cho, S DiVenere, A Wong, GK Ketterson, JB Meyer, JR AF Cho, S DiVenere, A Wong, GK Ketterson, JB Meyer, JR TI Thermoelectric transport properties of n-doped and p-doped Bi0.91Sb0.09 alloy thin films SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MOLECULAR-BEAM EPITAXY; BISMUTH-FILMS; BI; SUPERLATTICES AB In order to understand the doping behavior of extremely narrow band gap materials and to optimize their characteristics for use in a thermoelectric module, we performed n- and p- type doping experiments on semiconducting Bi0.91Sb0.09 alloy thin films using the group VI(IV) element Te(Sn) as donor (acceptor). Thermoelectric power (TEP), electrical resistivity, and Hall effect were studied in the range of temperatures 5-300 K. Increased Sn doping causes the TEP to change sign (from negative to positive) and the maximum in the TEP can be controlled with the dopant concentration. Increased Te doping causes the TEP to decrease. The maximum Te- oped electron concentration was about 5x10(20) cm(-3) and the highest Sn-doped hole concentration was about 1x10(21) cm(-3). Highly Sn- and Te-doped samples show degenerate behavior in the electrical resistivity, TEP and Hall measurements. (C) 1999 American Institute of Physics. [S0021-8979(99)02707-3]. C1 Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA. Northwestern Univ, Ctr Mat Res, Evanston, IL 60208 USA. USN, Res Lab, Washington, DC 20375 USA. HKUST, Dept Phys, Hong Kong, Peoples R China. Northwestern Univ, Dept Elect & Comp Engn, Evanston, IL 60208 USA. RP Cho, S (reprint author), Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA. RI Ketterson, John/B-7234-2009 NR 28 TC 26 Z9 27 U1 1 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 1 PY 1999 VL 85 IS 7 BP 3655 EP 3660 DI 10.1063/1.369729 PG 6 WC Physics, Applied SC Physics GA 180UQ UT WOS:000079403900040 ER PT J AU Lang, AR Makepeace, APW Alexander, WB McCormick, T Pehrsson, PE Butler, JE AF Lang, AR Makepeace, APW Alexander, WB McCormick, T Pehrsson, PE Butler, JE TI Optical microscopic, synchrotron X-ray topographic and reticulographic study of homoepitaxial CVD diamond SO JOURNAL OF CRYSTAL GROWTH LA English DT Article DE CVD diamond films; diamond homoepitaxy; X-ray topography; lattice misorientation measurement; surface topography; synchrotron X-ray diffraction contrast ID GROWTH; NITROGEN; FILMS; ANISOTROPY AB Surface topography and crystal-lattice perfection of homoepitaxial layers deposited by microwave plasma CVD on (0 0 1) and near-(0 0 1) facets polished on HPHT synthetic diamond are described. Optical micrographic techniques included birefringence, Nomarski and 2-beam interference. The synchrotron X-ray experiments comprised Laue topography plus a recently developed sensitive misorientation-measuring technique, reticulography. Two special circumstances enhanced information yield from the experiments. First, the substrate crystal was unusually strain-free and had a very low dislocation content. Second, epilayer growth had taken place in two stages, depositing thicknesses of 10 mu m and 30-34 mu m, respectively. This double deposition complicated the observations, but added features of scientific and practical interest. Epilayer cracking finally present had occurred almost entirely before the second growth stage. With assistance from quantitative data provided by reticulography, the X-ray diffraction properties of the substrate and epilayers are analysed. Lattice misorientations on the untreated lower surface of the substrate were only similar to 1 arcsec except dose to growth-sector boundaries and dislocation outcrops. The final epilayer growth surface above areas where cracking in the first epilayer was absent or sparse exhibited near-perfect-crystal diffraction behaviour. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Bristol, HH Wills Phys Lab, Bristol BS8 1TL, Avon, England. MENC Elect Mat Inc, St Peters, MS USA. Geocenters Inc, Ft Washington, MD 20744 USA. USN, Res Lab, Washington, DC 20375 USA. RP Lang, AR (reprint author), Univ Bristol, HH Wills Phys Lab, Tyndall Ave, Bristol BS8 1TL, Avon, England. RI Butler, James/B-7965-2008 OI Butler, James/0000-0002-4794-7176 NR 17 TC 6 Z9 6 U1 0 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 APR PY 1999 VL 200 IS 3-4 BP 446 EP 457 DI 10.1016/S0022-0248(99)00047-0 PG 12 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 188QN UT WOS:000079859800016 ER PT J AU Smith, KJ AF Smith, KJ TI Cutaneous epithelioid schwannoma: an unusual benign neurogenic tumor - Reply SO JOURNAL OF CUTANEOUS PATHOLOGY LA English DT Letter ID SOFT-TISSUE TUMOR C1 USN, Natl Med Ctr, Dept Dermatol, Bethesda, MD 20889 USA. RP Smith, KJ (reprint author), USN, Natl Med Ctr, Dept Dermatol, Bethesda, MD 20889 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0303-6987 J9 J CUTAN PATHOL JI J. Cutan. Pathol. PD APR PY 1999 VL 26 IS 4 BP 214 EP 214 DI 10.1111/j.1600-0560.1999.tb01832.x PG 1 WC Dermatology; Pathology SC Dermatology; Pathology GA 188YE UT WOS:000079876300009 ER PT J AU Eddy, CR Leonhardt, D Shamamian, VA Meyer, JR Hoffman, CA Butler, JE AF Eddy, CR Leonhardt, D Shamamian, VA Meyer, JR Hoffman, CA Butler, JE TI Characterization of the CH4/H-2/Ar high density plasma etching process for HgCdTe SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article DE CH4/H-2/Ar; HgCdTe; plasma etching ID MERCURY CADMIUM TELLURIDE; MOLECULAR-BEAM EPITAXY; HGTE-CDTE SUPERLATTICES; SPECTROSCOPIC ELLIPSOMETRY; HGTE/CDTE SUPERLATTICES; RESONANCE; HG1-XCDXTE; HYDROGEN; FABRICATION; CHEMISTRY AB High density plasma etching of mercury cadmium telluride using CH4/H-2/Ar plasma chemistries is investigated. Mass spectrometry is used to identify and monitor etch products evolving from the surface during plasma etching. The identifiable primary etch products are elemental Hg, TeH2, and Cd(CH3)(2). Their relative concentrations are monitored as ion and neutral fluxes (both in intensity and composition), ion energy and substrate temperature are varied. General insights are made into surface chemistry mechanisms of the etch process. These insights are evaluated by examining etch anisotropy and damage to the remaining semiconductor material. Regions of process parameter space best suited to moderate rate, anisotropic, low damage etching of HgCdTe are identified. C1 USN, Res Lab, Washington, DC 20375 USA. RP Eddy, CR (reprint author), Boston Univ, Dept Elect & Comp Engn, 8 St Marys St, Boston, MA 02215 USA. RI Butler, James/B-7965-2008 OI Butler, James/0000-0002-4794-7176 NR 24 TC 24 Z9 24 U1 1 U2 2 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD APR PY 1999 VL 28 IS 4 BP 347 EP 354 DI 10.1007/s11664-999-0231-7 PG 8 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 183JM UT WOS:000079550500001 ER PT J AU Burger, CL Mork, TO Hutter, JW Nicoll, B AF Burger, CL Mork, TO Hutter, JW Nicoll, B TI Direct digital radiography versus conventional radiography for estimation of canal length in curved canals SO JOURNAL OF ENDODONTICS LA English DT Article ID RADIO VISIOGRAPHY; RADIOVISIOGRAPHY; INVITRO AB A recent development in direct digital radiography (DDR) has made it possible to make additive multiple point (click) measurements of onscreen images. Canal length was examined using four estimation methods: measurement of a conventional D-speed film radiograph, and onscreen DDR allowing two clicks, six clicks, and an unlimited number of clicks of the measuring device. Thirty extracted human teeth with root curvatures ranging from 7 degrees to 47 degrees (Schneider method) were examined. Actual canal length was measured using a millimeter rule and x2 magnification. Teeth were mounted and prepared for conventional and DDR imaging. Estimated canal length was determined by three board-certified endodontists using each of the four techniques. A two-way analysis of variance indicated that all radiographic techniques resulted in canal lengths that were significantly different from the true canal length, and there was no significant difference between experimental groups, regardless of the canal curvature. C1 USN, Sch Dent, Endodont Dept, Bethesda, MD 20814 USA. USN, Sch Dent, Adv Specialty Educ Program Endodont, Bethesda, MD 20814 USA. USN, Dent Res Inst Detachment, Bethesda, MD USA. RP Hutter, JW (reprint author), Boston Univ, Sch Dent, 100 E Newton St, Boston, MA 02118 USA. NR 16 TC 20 Z9 23 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0099-2399 J9 J ENDODONT JI J. Endod. PD APR PY 1999 VL 25 IS 4 BP 260 EP 263 DI 10.1016/S0099-2399(99)80155-1 PG 4 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 182JQ UT WOS:000079496200010 PM 10425952 ER PT J AU Funsten, HO Gosling, JT Riley, P St Cyr, OC Forsyth, RJ Howard, RA Schwenn, R AF Funsten, HO Gosling, JT Riley, P St Cyr, OC Forsyth, RJ Howard, RA Schwenn, R TI Combined Ulysses solar wind and SOHO coronal observations of several west limb coronal mass ejections SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID INTERPLANETARY MAGNETIC CLOUDS; INTER-PLANETARY SHOCK; SMM OBSERVATIONS; FIELD STRUCTURE; EVENTS; SPACECRAFT; SPEEDS; LASCO; FLOWS; FLUX AB From October 1996 to January 1997, Ulysses was situated roughly above the west limb of the Sun as observed from Earth at a heliocentric distance of about 4.6 AU and a latitude of about 25 degrees. This presents the first opportunity to compare Solar and Heliospheric Observatory (SOHO) limb observations of coronal mass ejections (CMEs) directly with their solar wind counterparts far from the Sun using the Ulysses data. During this interval, large eruptive events were observed above the west limb of the Sun by the Large Angle Spectrometric Coronagraph (LASCO) on SOHO on October 5, November 28, and December 21-25, 1996, Using the combined plasma and magnetic field data from Ulysses, the October 5 event was clearly identified by several distinguishing signatures as a CME. The November 28 event was also identified as a CME that trailed fast ambient solar wind, although it was identified only by an extended interval of counterstreaming suprathermal electrons. The December 21 event was apparently characterized by a B-day interval of nearly radial field and a plasma rarefaction. For the numerous eruptive events observed by the LASCO coronagraph during December 23-25, Ulysses showed no distinct, individual CMEs, perhaps because of intermingling of two or more of the eruptive events. By mapping the Ulysses observations back in time to the Sun assuming a constant flow speed, we have identified intervals of plasma that were accelerated or decelerated between the LASCO and Ulysses observations. C1 Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BZ, England. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Sci Applicat Int Corp, San Diego, CA 92121 USA. Computat Phys Inc, USN, Res Lab, Washington, DC 20375 USA. Max Planck Inst Aeron, D-37189 Katlenburg Lindau, Germany. RP Funsten, HO (reprint author), Univ London Imperial Coll Sci Technol & Med, Blackett Lab, Prince Consort Rd, London SW7 2BZ, England. EM hfunsten@lanl.gov; jgosling@lanl.gov; uk2@iris023.saic.com; cst@sdac.nascom.nasa.gov; rforsyth@ic.ac.uk; howard@cronus.nrl.navy.mil; schwenn@linax1.mpae.gwdg.de RI Funsten, Herbert/A-5702-2015 OI Funsten, Herbert/0000-0002-6817-1039 NR 39 TC 17 Z9 17 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD APR 1 PY 1999 VL 104 IS A4 BP 6679 EP 6689 DI 10.1029/1998JA900088 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 182CU UT WOS:000079481600001 ER PT J AU Ichino, M Mor, G Conover, J Weiss, WR Takeno, M Ishii, KJ Klinman, DM AF Ichino, M Mor, G Conover, J Weiss, WR Takeno, M Ishii, KJ Klinman, DM TI Factors associated with the development of neonatal tolerance after the administration of a plasmid DNA vaccine SO JOURNAL OF IMMUNOLOGY LA English DT Article ID HEPATITIS-B VIRUS; CIRCUMSPOROZOITE PROTEIN; T-CELLS; IMMUNE-RESPONSES; NEWBORN MICE; IMMUNIZATION; INJECTION; INDUCTION; MALARIA; ACQUISITION AB A plasmid DNA vaccine encoding the circumsporozoite protein of malaria (pCSP) induces tolerance rather than immunity when administered to newborn mice. We find that this tolerance persists for >1 yr after neonatal pCSP administration and interferes with the induction of protective immunity in animals challenged with live sporozoites. Susceptibility to tolerance induction wanes rapidly with age, disappearing within 1 wk of birth. Higher doses of plasmid are more tolerogenic, and susceptibility to tolerance is not MHC-restricted. CD8(+) T cells from tolerant mice suppress the in vitro Ag-specific immune response of cells from adult mice immunized with pCSP, Similarly, CD8(+) T cells from tolerant mice transfer nonresponsiveness to naive syngeneic recipients, These findings clarify the cellular basis and factors contributing to the development of DNA vaccine-induced neonatal tolerance. C1 US FDA, Sect Retroviral Immunol, Ctr Biol Evaluat & Res, Bethesda, MD 20892 USA. USN, Med Res Inst, Malaria Program, Bethesda, MD 20889 USA. RP Klinman, DM (reprint author), US FDA, Sect Retroviral Immunol, Ctr Biol Evaluat & Res, Bldg 29A,Room 3D10, Bethesda, MD 20892 USA. EM klinman@al.cber.fda.gov RI Ishii, Ken/B-1685-2012 OI Ishii, Ken/0000-0002-6728-3872 NR 34 TC 36 Z9 38 U1 1 U2 1 PU AMER ASSOC IMMUNOLOGISTS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0022-1767 J9 J IMMUNOL JI J. Immunol. PD APR 1 PY 1999 VL 162 IS 7 BP 3814 EP 3818 PG 5 WC Immunology SC Immunology GA 178QT UT WOS:000079278000012 PM 10201898 ER PT J AU Pistek, P La Violette, PE AF Pistek, P La Violette, PE TI Observations of the suppression of tide-generated nonlinear internal wave packets in the Strait of Gibraltar SO JOURNAL OF MARINE SYSTEMS LA English DT Article DE internal wave; tide; wind; atmospheric pressure; water flow ID SEA AB An examination of October 1983 instrumented moorings data from the western Alboran Sea indicates that nonlinear internal wave packets that normally emanate from the Strait of Gibraltar into the Alboran Sea, were absent during a period when tide conditions should have generated such waves. Other long-term mooring data of the region shows that on occasion, non tide-related absences or reductions in strength of the wave packets has occurred. Available data for wind, atmospheric pressure, surface and deep flow for the period were examined to derive possible causes for the absence of the internal waves. A hypothesis is presented that suggests an increase in the outflow of Mediterranean Water over the main bathymetric sill east of the Strait of Gibraltar may have been the cause. Such an increase may have hindered or strongly limited the generation of internal waves at and near high tide. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. Heron Labs, Waveland, MS 39529 USA. RP Pistek, P (reprint author), USN, Res Lab, Stennis Space Ctr, MS 39529 USA. EM ppistek@nrlssc.navy.mil; laviolet@datasynch.com NR 22 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0924-7963 J9 J MARINE SYST JI J. Mar. Syst. PD APR PY 1999 VL 20 IS 1-4 BP 113 EP 128 DI 10.1016/S0924-7963(98)00073-6 PG 16 WC Geosciences, Multidisciplinary; Marine & Freshwater Biology; Oceanography SC Geology; Marine & Freshwater Biology; Oceanography GA 184LZ UT WOS:000079614800007 ER PT J AU Robinson, AR Sellschopp, J Warn-Varnas, A Leslie, WG Lozano, CJ Haley, PJ Anderson, LA Lermusiaux, PFJ AF Robinson, AR Sellschopp, J Warn-Varnas, A Leslie, WG Lozano, CJ Haley, PJ Anderson, LA Lermusiaux, PFJ TI The Atlantic ionian stream SO JOURNAL OF MARINE SYSTEMS LA English DT Article DE Atlantic ionian stream; Strait of Sicily; Error Subspace Statistical Estimation ID VARIABILITY; CIRCULATION AB This paper describes some preliminary results of the cooperative effort between SACLANT Undersea Research Centre and Harvard University in the development of a regional descriptive and predictive capability for the Strait of Sicily. The aims of the work have been to: (1) determine and describe the underlying dynamics of the region; and, (2) rapidly assess synoptic oceanographic conditions through measurements and modeling. Based on the 1993-1996 surveys, a picture of some semi-permanent features which occur in the Strait of Sicily is beginning to emerge. Dynamical circulation studies, with assimilated data from the surveys, indicate the presence of an Adventure Bank Vortex (ABV), Maltese Channel Crest (MCC). and Ionian Shelf Break Vortex (IBV). A schematic water mass model has been developed for the region. Results from the Rapid Response 96 real-time numerical modeling experiments are presented and evaluated. A newly developed data assimilation methodology, Error Subspace Statistical Estimation (ESSE) is introduced. The ideal Error Subspace spans and tracks the scales and processes where the dominant, most energetic, errors occur, making this methodology especially useful in real-time adaptive sampling. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Harvard Univ, Dept Earth & Planetary Sci, Div Appl Sci, Cambridge, MA 02138 USA. SACLANT Undersea Res Ctr, La Spezia, Italy. USN, Res Lab, Stennis Space Ctr, MS 39529 USA. RP Robinson, AR (reprint author), Harvard Univ, Dept Earth & Planetary Sci, Div Appl Sci, 29 Oxford St, Cambridge, MA 02138 USA. RI Lermusiaux, Pierre/H-6003-2011 NR 13 TC 83 Z9 83 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0924-7963 J9 J MARINE SYST JI J. Mar. Syst. PD APR PY 1999 VL 20 IS 1-4 BP 129 EP 156 DI 10.1016/S0924-7963(98)00079-7 PG 28 WC Geosciences, Multidisciplinary; Marine & Freshwater Biology; Oceanography SC Geology; Marine & Freshwater Biology; Oceanography GA 184LZ UT WOS:000079614800008 ER PT J AU Poulain, PM AF Poulain, PM TI Drifter observations of surface circulation in the Adriatic Sea between December 1994 and March 1996 SO JOURNAL OF MARINE SYSTEMS LA English DT Article DE drifter observations; surface circulation; Adriatic Sea ID GENERAL-CIRCULATION; SCALE CIRCULATION; VARIABILITY; CURRENTS AB The trajectories of satellite-tracked drifters are used to describe the characteristics of the subtidal surface circulation in the Adriatic Sea between December 1994 and March 1996. The mean surface circulation inferred from the drifter velocities consists of an elongated basin-wide cyclonic gyre with northward flow on the eastern side and return southward currents near the Italian coast (western side). This global circulation feature is composed of two sub-basin cyclonic, circulatory velocity patterns around the two main deeps of the Adriatic, i.e., the Jabuka and the South Adriatic Pits. The mean currents are maximum (greater than 40 cm s(-1)) near the outside (coastal) perimeter of these features. Specific zones of horizontal convergence of the mean flow were identified by converging drifters. Other areas in the open sea appeared to be diverging as drifters were reluctant to enter them. The seasonal modulation of the surface circulation was resolved in the lower southern Adriatic Sea and in the Strait of Otranto, An enhanced horizontal shear (northward flow on the eastern flank and southward currents on the western side) in the strait and an increased cyclonic gyre circulation around the South Adriatic Pit were observed in winter. The inflow of Ionian water and the subsequent cyclonic veering around the South Adriatic Pit are minimum in spring. In summer, the southward currents outflowing on the Italian shelf are maximum. Qualitative comparison between the drifter-inferred velocities and contemporaneous moored current observations discloses substantial vertically coherent current variations within the top 50 m of water that give rise to significant transport variability. In addition to the seasonal variations, surface subtidal velocity fluctuations with scales ranging from a few days to a few weeks are ubiquitous in both the drifter and moored observations. They are due to transient wind events, to changes in the buoyancy input (river runoff) and to instability of the mean flow in the form of mesoscale eddies, jets and filaments. (C) 1999 Elsevier Science B.V, All rights reserved. C1 SACLANT Undersea Res Ctr, I-19138 La Spezia, Italy. RP Poulain, PM (reprint author), USN, Postgrad Sch, Dept Oceanog, Code OC-Pn, Monterey, CA 93943 USA. EM poulain@oc.nps.navy.mil OI Poulain, Pierre-Marie/0000-0003-1342-8463 NR 28 TC 74 Z9 74 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0924-7963 J9 J MARINE SYST JI J. Mar. Syst. PD APR PY 1999 VL 20 IS 1-4 BP 231 EP 253 DI 10.1016/S0924-7963(98)00084-0 PG 23 WC Geosciences, Multidisciplinary; Marine & Freshwater Biology; Oceanography SC Geology; Marine & Freshwater Biology; Oceanography GA 184LZ UT WOS:000079614800013 ER PT J AU Porch, D AF Porch, D TI What if? Strategic alternatives of WWII SO JOURNAL OF MILITARY HISTORY LA English DT Book Review C1 Naval Postgraduate Sch, Monterey, CA USA. RP Porch, D (reprint author), Naval Postgraduate Sch, Monterey, CA USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU SOC MILITARY HISTORY PI LEXINGTON PA C/O VIRGINIA MILITARY INST, GEORGE C MARSHALL LIBRARY, LEXINGTON, VA 24450-1600 USA SN 0899-3718 J9 J MILITARY HIST JI J. Mil. Hist. PD APR PY 1999 VL 63 IS 2 BP 478 EP 480 DI 10.2307/120688 PG 3 WC History SC History GA 183HA UT WOS:000079547100045 ER PT J AU Makeig, S Westerfield, M Jung, TP Covington, J Townsend, J Sejnowski, TJ Courchesne, E AF Makeig, S Westerfield, M Jung, TP Covington, J Townsend, J Sejnowski, TJ Courchesne, E TI Functionally independent components of the late positive event-related potential during visual spatial attention SO JOURNAL OF NEUROSCIENCE LA English DT Article DE electroencephalogram; event-related potential; evoked response; independent component analysis; reaction time; P300; motor; inhibition; frontoparietal; orienting ID BLIND SEPARATION; LEARNING ALGORITHM; BRAIN RESPONSES; REACTION-TIME; INFORMATION; TASKS; P300; MISALLOCATION; VARIANCE; CORTEX AB Human event-related potentials (ERPs) were recorded from 10 subjects presented with visual target and nontarget stimuli at five screen locations and responding to targets presented at one of the locations. The late positive response complexes of 25-75 ERP average waveforms from the two task conditions were simultaneously analyzed with Independent Component Analysis, a new computational method for blindly separating linearly mixed signals. Three spatially fixed, temporally independent, behaviorally relevant, and physiologically plausible components were identified without reference to peaks in single-channel waveforms. A novel frontoparietal component (P3f) began at similar to 140 msec and peaked, in faster responders, at the onset of the motor command. The scalp distribution of P3f appeared consistent with brain regions activated during spatial orienting in functional imaging experiments. A longer-latency large component (P3b), positive over parietal cortex, was followed by a postmotor potential (Pmp) component that peaked 200 msec after the button press and reversed polarity near the central sulcus. A fourth component associated with a left frontocentral nontarget positivity (Pnt) was evoked primarily by target-like distracters presented in the attended location. When no distracters were presented, responses of five faster-responding subjects contained largest P3f and smallest Pmp components; when distracters were included, a Pmp component appeared only in responses of the five slower-responding subjects. Direct relationships between component amplitudes, latencies, and behavioral responses, plus similarities between component scalp distributions and regional activations reported in functional brain imaging experiments suggest that P3f, Pmp, and Pnt measure the time course and strength of functionally distinct brain processes. C1 Naval Hlth Res Ctr, San Diego, CA 92186 USA. Childrens Hosp, Res Ctr, San Diego, CA 92123 USA. Salk Inst Biol Studies, Howard Hughes Med Inst, Computat Neurobiol Lab, La Jolla, CA 92037 USA. Univ Calif San Diego, Dept Biol, La Jolla, CA 92093 USA. Univ Calif San Diego, Dept Neurosci, La Jolla, CA 92093 USA. RP Makeig, S (reprint author), Naval Hlth Res Ctr, POB 85122, San Diego, CA 92186 USA. FU NIMH NIH HHS [MH36840]; NINDS NIH HHS [NS34155] NR 72 TC 250 Z9 251 U1 3 U2 15 PU SOC NEUROSCIENCE PI WASHINGTON PA 11 DUPONT CIRCLE, NW, STE 500, WASHINGTON, DC 20036 USA SN 0270-6474 J9 J NEUROSCI JI J. Neurosci. PD APR 1 PY 1999 VL 19 IS 7 BP 2665 EP 2680 PG 16 WC Neurosciences SC Neurosciences & Neurology GA 179TD UT WOS:000079344400025 PM 10087080 ER PT J AU Garfield, N Collins, CA Paquette, RG Carter, E AF Garfield, N Collins, CA Paquette, RG Carter, E TI Lagrangian exploration of the California undercurrent, 1992-85 SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article ID COASTAL TRANSITION ZONE; SURFACE CIRCULATION; SEASONAL VARIABILITY; STATISTICAL-ANALYSIS; MEDDY FORMATION; CURRENT SYSTEM; DRIFTERS; WATER; FLOATS; FLOW AB During the period 1992-95, nineteen isobaric RAFOS floats, placed in the California Undercurrent at intermediate depths (150-600 m) off Monterey and San Francisco, California, reveal a region of varying width of subsurface, poleward flow adjacent to the continental margin. The float trajectories exhibit three patterns: poleward how in the undercurrent; reversing, but predominately alongshore, flow adjacent to the continental margin; and; farther offshore, anticyclonic motion accompanied by slow westward drift. Flow continuity of the undercurrent exists between Pt. Reyes and at least Cape Mendocino with an average speed dependent on the float depth. Speeds were variable, bur common features were acceleration occurring to the south of Pt. Arena and deceleration to the north of Cape Mendocino. An important mechanism for floats, and water, to enter the ocean interior from the undercurrent is through the formation of submesoscale coherent vortices. C1 USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. RP Garfield, N (reprint author), San Francisco State Univ, Dept Geosci, 1600 Holloway Ave, San Francisco, CA 94132 USA. NR 57 TC 56 Z9 56 U1 0 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-3670 J9 J PHYS OCEANOGR JI J. Phys. Oceanogr. PD APR PY 1999 VL 29 IS 4 BP 560 EP 583 DI 10.1175/1520-0485(1999)029<0560:LEOTCU>2.0.CO;2 PG 24 WC Oceanography SC Oceanography GA 187VZ UT WOS:000079809900002 ER PT J AU Huba, JD Lyon, JG AF Huba, JD Lyon, JG TI A new 3D MHD algorithm: the distribution function method SO JOURNAL OF PLASMA PHYSICS LA English DT Article ID GAS-KINETIC-THEORY; MAGNETOHYDRODYNAMICS AB A new three-dimensional (3D) magnetohydrodynamic (MHD) algorithm is described. The 3D MHD equations are solved in conservative form using a finite volume scheme. The hydrodynamic variables in a cell are updated bq calculating fluxes across the cell inter faces. The fluxes of mass, momentum and energy across cell interfaces are calculated by integrating a Boltzmann-like distribution function over velocity space. The novel feature of the method is that the distribution function incorporates most of the electromagnetic terms. In addition, the electric field along cell edges, which is used to update the magnetic field at cell faces, is also calculated using the Boltzmann-like distribution funct ion. An important aspect of the method is that it provides a theoretical framework to incorporate additional terms in the 3D MHD equations (e.g. an anisotropic ion stress tensor and anisotropic temperature distributions). C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Dartmouth Coll, Hanover, NH 03755 USA. RP Huba, JD (reprint author), USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. NR 11 TC 18 Z9 18 U1 2 U2 3 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0022-3778 J9 J PLASMA PHYS JI J. Plasma Phys. PD APR PY 1999 VL 61 BP 391 EP 405 DI 10.1017/S0022377899007503 PN 3 PG 15 WC Physics, Fluids & Plasmas SC Physics GA 226JB UT WOS:000082015900002 ER PT J AU Diachok, O AF Diachok, O TI Effects of absorptivity due to fish on transmission loss in shallow water SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID ACOUSTIC SCATTERING; TARGET STRENGTHS; BUBBLE CLOUDS; PELAGIC FISH; SCHOOLS; BEHAVIOR; MODELS; SONAR; WAVE; SIZE AB Absorption losses at the resonance frequencies of sardines, 1.3 kHz (18 dB) at night, 1.7 kHz (15 dB) during the day and 2.7 kHz (35 dB) at dawn, were observed at a range of 12 km at a shallow wafer site in the Gulf of Lion in September of 1995. These observations were made during Modal Lion, a multidisciplinary experiment, which was designed to isolate absorptivity due to fish from other effects on long range propagation. Systematic changes in the resonance frequency of dispersed sardines were consistent with concurrent echo sounder observations of the vertical migration of sardines at twilight. Comparison of transmission loss measurements with a numerical sound propagation model that incorporates absorption layers in the water column permitted estimation of the average absorption coefficient, depth and thickness of absorption layers. Depths and thickness of layers estimated from sound propagation measurements were in good agreement with echo sounder data. Measured resonance frequencies, f(0), of dispersed fish were in good agreement with theoretical computations based on measured swim bladder dimensions. The measured resonance frequency of sardines in schools, which were at a depth of about 65 m, was about 0.6 times the resonance frequency of dispersed sardines. The observed frequency shift is consistent with an analytical equation of the fundamental resonance frequency of a "cloud" of bubbles, an average separation between fish in schools of about 0.8 fish lengths and 5 x 10(3) fish per school. These estimates are consistent with previously published estimates of these parameters. The resonance frequencies of other absorption lines are consistent with the hypothesis that absorptivity due to sardines generally manifests itself in pairs of absorption lines, which correspond to the resonance frequencies of an ensemble of individual sardines, and the resonance frequencies of an ensemble of schools. Matching of theoretical calculations with inferences of the absorption coefficient permitted estimation of the average number of dispersed sardines per unit volume, which also consistent with previously published estimates. The results presented here suggest the possibility of long term tomographic mapping of fish parameters over large areas using broadband transmission loss measurements. (C) 1999 Acoustical Society of America. [S0001-4966(99)04703-7]. C1 USN, Res Lab, Washington, DC 20375 USA. RP USN, Res Lab, Washington, DC 20375 USA. NR 86 TC 22 Z9 24 U1 0 U2 1 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 APR PY 1999 VL 105 IS 4 BP 2107 EP 2128 DI 10.1121/1.426816 PG 22 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 188FW UT WOS:000079837000005 ER PT J AU Caveny, DM Del Balzo, DR Leclere, JH Ioup, GE AF Caveny, DM Del Balzo, DR Leclere, JH Ioup, GE TI Performance of sinusoidally deformed hydrophone line arrays SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID SHAPE AB It is well known that array deformations can distort beam patterns and introduce bearing errors if the beamformer assumes linearity. It is also known that deformed arrays can resolve left-right ambiguities, provided the shape is known. In this work, these two effects are studied for undamped and damped sinusoidally deformed arrays with small deformation amplitudes in the horizontal (x,y) plane only. By use of fixed are-length separations along the array, the hydrophone (x,y) coordinates are determined numerically and the error in assuming equal x spacing is summarized for a sample array. Array-response patterns are analyzed for two conditions: (1) when the deformed array shape is assumed linear and (2) when the deformed array shape is known exactly. Degradations resulting from assuming linearity and the ability to resolve left-right ambiguities are discussed in terms of reduced gain, degraded angular resolution, and bearing errors. Shape-unknown signal-gain degradation ranges to 7 dB at broadside, but is less than 1 dB near endfire. For the shape-known case, signal gain for the true peak is greater than signal gain for the ambiguous peak by up to 9 dB for sources at broadside and to just over 2.5 dB for arrivals near endfire. (C) 1999 Acoustical Society of America. [S0001-4966(99)06103-2]. C1 USN, Res Lab, Stennis Space Ctr, MS 39529 USA. Univ New Orleans, Dept Phys, New Orleans, LA 70148 USA. RP Caveny, DM (reprint author), Coll Charleston, Dept Math, Charleston, SC 29424 USA. NR 19 TC 5 Z9 7 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD APR PY 1999 VL 105 IS 4 BP 2203 EP 2209 DI 10.1121/1.426824 PG 7 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 188FW UT WOS:000079837000013 ER PT J AU Moffett, MB Jevnager, MD Gilardi, SS Powers, JM AF Moffett, MB Jevnager, MD Gilardi, SS Powers, JM TI Biased lead zirconate titanate as a high-power transduction material SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB High-power, underwater transducers utilizing polarized piezoelectric ceramic material are usually limited in drive amplitude so that depolarization does not occur, but application of a dc bias field in the polarization direction allows the use of higher ac drive fields. To demonstrate the feasibility of biased operation as a means of achieving higher power, a thin-walled, spherical-shell transducer was constructed of Channel 5800 and tested in NUWC's Acoustic Pressure Tank Facility at a hydrostatic pressure of 1400 psig (9.65 MPa). The transducer was successfully driven to 33 V/mil (1.3 MV/m) rms with an accompanying bias field of 31 V/mil (1.2 MV/m). The source level was 206 dB re: 1 mu Pa.m at 61 kHz, corresponding to a 10-dB improvement over the unbiased drive limit of 10 V/mil (0.4 MV/m) rms and 196 dB re: 1 mu Pa.m. (C) 1999 Acoustical Society of America. [S0001-4966(99)04204-6]. C1 USN, Undersea Warfare Ctr, Newport Div, Newport, RI 02841 USA. Georgia Tech Res Inst, Atlanta, GA 30318 USA. Interface Engn, Mystic, CT 06355 USA. RP Moffett, MB (reprint author), USN, Undersea Warfare Ctr, Newport Div, Newport, RI 02841 USA. NR 9 TC 4 Z9 4 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD APR PY 1999 VL 105 IS 4 BP 2248 EP 2251 DI 10.1121/1.426830 PG 4 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 188FW UT WOS:000079837000019 ER PT J AU Carroll, GP AF Carroll, GP TI The effect of sensor placement errors on cylindrical near-field acoustic holography SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID NEARFIELD AB This paper presents the results of a numerical investigation of the effects of sensor placement errors on the accuracy of cylindrical near-field acoustic holography (NAH). Results are presented using two data sets, one corresponding to numerically generated hologram plane pressures for a periodically ribbed cylindrical shell, and the other to measured hologram plane pressures for an identical small scale (1/50 scale) physical model. The numerically generated hologram plane pressures are valid in the range ka<4.0, while the experimental data are valid up to ka<20. The motivation for this investigation is to determine whether or not large scale implementation of NAH is feasible given the potentially increased sensor placement inaccuracies which are likely to be encountered at large scale. The effect of both random and systematic axial, circumferential, and radial sensor placement errors are assessed and compared. The majority of the results are presented as wave number comparisons of contaminated and uncontaminated surface pressure reconstructions. It is shown that, as is known to be the case for contamination by background noise, sensor placement errors also result in high wave number noise. Therefore, the success of implementing NAH at large scale when these sensor placement errors are present relies on the selection of a low-pass wave number filter suitable for removing these contaminating factors while preserving the cylinders actual wave number response. (C) 1999 Acoustical Society of America. [S0001-4966(99)04704-9]. C1 USN, Carderock Div, Ctr Surface Warfare, W Bethesda, MD 20817 USA. RP Carroll, GP (reprint author), USN, Carderock Div, Ctr Surface Warfare, 9500 MacArthur Blvd, W Bethesda, MD 20817 USA. NR 14 TC 6 Z9 8 U1 1 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD APR PY 1999 VL 105 IS 4 BP 2269 EP 2276 DI 10.1121/1.426833 PG 8 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 188FW UT WOS:000079837000022 ER PT J AU Zalesak, JF AF Zalesak, JF TI Transfer coupler reciprocity: A new low-frequency coupler-reciprocity technique for the absolute calibration of field hydrophones under full environmental conditions SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB The reciprocity coupler system in the Low-Frequency Facility (LOFAC) at the Underwater Sound Reference Divsion (USRD) of the Naval Undersea Warfare Center is a closed-chamber environmentally controlled system for the absolute calibration of standard hydrophones at low frequencies. There is a need to extend this capability to field hydrophones that are not specifically designed for use in a reciprocity coupler. The transfer reciprocity method described here is an answer to this need. An error analysis is presented indicating the current state of the existing reciprocity coupler including the transfer reciprocity method. The analysis shows that there is a systematic error which can be eliminated by correcting the sensitivities obtained using the transfer reciprocity method. This correction has a frequency independent component of 0.31 dB and a frequency dependent component of 0.1 dB at 700 Hz and 1.0 dB at 2000 Hz. After correction for the systematic error, the uncertainty in sensitivity is +/-0.25 dB for frequencies below 1000 Hz, growing to +/-0.35 dB for frequencies near 2000 Hz. [S0001-4966(99)02304-8]. C1 USN, Undersea Warfare Ctr, Underwater Sound Reference Div, Newport, RI 02841 USA. RP Zalesak, JF (reprint author), USN, Undersea Warfare Ctr, Underwater Sound Reference Div, 1176 Howell St, Newport, RI 02841 USA. NR 7 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 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD APR PY 1999 VL 105 IS 4 BP 2342 EP 2349 DI 10.1121/1.426840 PG 8 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 188FW UT WOS:000079837000029 ER PT J AU Fitzpatrick, RE Smith, SR Sriprachya-anunt, S AF Fitzpatrick, RE Smith, SR Sriprachya-anunt, S TI Depth of vaporization and the effect of pulse stacking with a high-energy, pulsed carbon dioxide laser SO JOURNAL OF THE AMERICAN ACADEMY OF DERMATOLOGY LA English DT Article ID THERMAL-DAMAGE; DURATION; ABLATION AB Background: Laser resurfacing of photodamaged skin has become popular, but questions regarding its safety with regard to the risks of scarring have arisen. Objective: This study was designed to investigate the depth of vaporization and residual thermal necrosis of single-pulse vaporization and multiple passes versus pulse-stacking and multiple passes. The potential significance of operator technique and laser parameters is considered. Methods: Skin samples from surgical excisions were treated by means of a Coherent Ultrapulse carbon dioxide laser at 250 mJ per pulse and 500 mi per pulse with a 3 mm collimated beam and a repetition rate of 10 Hz. A total of 70 treatment areas were performed. Blinded analysis of the histologic effects of single-pulse, double-pulse, and triple-pulse vaporization after 1 through 10 passes was undertaken. Results: A plateau of vaporization was observed after 3 passes at both 250 and 500 mJ whether single-, double-, or triple-pulse vaporization was used. This plateau occurs at approximately 100 to 250 mu m from the skin surface. Thermal necrosis is well controlled only with single-pulse vaporization. There is a direct linear increase in the depth of thermal necrosis both with the number of pulses stacked and the number of passes. Conclusion: Pulsed carbon dioxide laser resurfacing is a safe and self-limited procedure if a pulse width of less than 1 msec is used with single-pulse vaporization and fluences of 3.5 J/cm(2) and 7.0 J/cm(2). There appears to be little justification for performing more than 3 or 4 passes. Pulse stacking may significantly increase residual thermal necrosis, thereby increasing the risk of scarring. Operator technique may be significant in avoidance of this occurrence. C1 Dermatol Associates San Diego Cty Inc, Encinitas, CA 92024 USA. Univ Calif San Diego, Dept Med, Div Dermatol, San Diego, CA 92103 USA. USN, Med Ctr, Dept Dermatol, San Diego, CA 92152 USA. Pornkasem Skin & Laser Ctr, Bangkok, Thailand. RP Smith, SR (reprint author), Dermatol Associates San Diego Cty Inc, 477 N El Camino Real B-303, Encinitas, CA 92024 USA. NR 14 TC 36 Z9 37 U1 0 U2 1 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0190-9622 J9 J AM ACAD DERMATOL JI J. Am. Acad. Dermatol. PD APR PY 1999 VL 40 IS 4 BP 615 EP 622 DI 10.1016/S0190-9622(99)70447-0 PG 8 WC Dermatology SC Dermatology GA 179TA UT WOS:000079344100016 PM 10188684 ER PT J AU Vachet, RW McElvany, SW AF Vachet, RW McElvany, SW TI Application of external customized waveforms to a commercial quadrupole ion trap SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID INVERSE FOURIER-TRANSFORM; BROAD-BAND EXCITATION; FILTERED NOISE FIELD; MASS-SPECTROMETER; SELECTIVE INJECTION; SPECTRA AB The Finnigan LCQ quadrupole ion trap has recently become part of the repertoire of instruments for many analytical laboratories. The LCQ commercial design, while employing complex waveforms to manipulate ions, does not allow the application of many state-of-the-art user-defined waveforms that enable one to perform other complex ion manipulations. The work presented here describes the simple modifications made to the LCQ electronics to allow the application of external customized waveforms. Results show that externally generated waveforms can be applied to the endcap electrodes while still working within the context of the commercial software and hardware. Double resonance, multiple ion isolation, and multiple ion excitation experiments are demonstrated to reveal the effectiveness of these modifications. (C) 1999 American Society for Mass Spectrometry. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. RP McElvany, SW (reprint author), USN, Res Lab, Div Chem, Code 6113, Washington, DC 20375 USA. NR 17 TC 9 Z9 9 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD APR PY 1999 VL 10 IS 4 BP 355 EP 359 DI 10.1016/S1044-0305(99)00007-0 PG 5 WC Biochemical Research Methods; Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Biochemistry & Molecular Biology; Chemistry; Spectroscopy GA 221PP UT WOS:000081735700010 ER PT J AU Xu, Q Gao, JD AF Xu, Q Gao, JD TI Generalized adjoint for physical processes with parameterized discontinuities. Part VI: Minimization problems in multidimensional space SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID ASSIMILATION AB Generalized adjoint with modified discretization and generalized coarse-grain adjoint are derived for a vector system of equations that contains parameterized on/off switches. With vector examples, it is shown that the conventional adjoint minimization may have a convergence problem in multidimensional space. The problem can be solved by the generalized adjoint with modified discretization or by the generalized coarse-grain adjoint without modifying the traditional discretization in the forward model. C1 USN, Res Lab, Monterey, CA 93943 USA. Univ Oklahoma, CAPS, Norman, OK 73019 USA. RP Xu, Q (reprint author), USN, Res Lab, 7 Grace Hopper Dr, Monterey, CA 93943 USA. NR 11 TC 15 Z9 17 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD APR 1 PY 1999 VL 56 IS 7 BP 994 EP 1002 DI 10.1175/1520-0469(1999)056<0994:GAFPPW>2.0.CO;2 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 178PF UT WOS:000079274500007 ER PT J AU Chen, MS Brandow, SL Dulcey, CS Dressick, WJ Taylor, GN Bohland, JF Georger, JHG Pavelchek, EK Calvert, JM AF Chen, MS Brandow, SL Dulcey, CS Dressick, WJ Taylor, GN Bohland, JF Georger, JHG Pavelchek, EK Calvert, JM TI Channel-constrained electroless metal deposition on ligating self-assembled film surfaces SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID NI DEPOSITION; X-RAY; METALLIZATION; LITHOGRAPHY; FABRICATION; CATALYSTS; POLYMERS AB Channel-constrained metallization is described as a novel process for fabrication of metal features useful as etchmasks and electrical interconnects in microelectronics applications. The method creates a requisite surface reactivity template through patterned exposure and development of photoresist films to open channels to an underlying ligand self-assembled film. Subsequent electroless metal deposition occurs selectively at exposed ligand sites in the channels, which constrain lateral metal growth detrimental to feature critical dimension (CD) control during plating. A characterization of the individual process steps is presented using a positive tone photoresist system as an example. Determination of the exposure and development conditions that promote clearance of photoresist residues from the channels while maintaining adequate feature CD control is identified as an important issue in successfully performing the process. The process has been successfully demonstrated using optical exposure sources and is compatible with a range of substrates relevant for electronics applications, including Si. The high plasma etching selectivity of a thin Ni metal masking layer was used in the fabrication of high aspect ratio structures (less than or equal to 5:1) in Si. (C) 1999 The Electrochemical Society. S0013-4651(98)03-130-9. All rights reserved. C1 USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. Shipley Co Inc, Marlborough, MA 01752 USA. RP Chen, MS (reprint author), USN, Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. NR 49 TC 64 Z9 64 U1 0 U2 6 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 EI 1945-7111 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD APR PY 1999 VL 146 IS 4 BP 1421 EP 1430 DI 10.1149/1.1391780 PG 10 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 187WK UT WOS:000079811000028 ER PT J AU Merrill, LL Newell, CE Thomsen, CJ Gold, SR Milner, JS Koss, MP Rosswork, SG AF Merrill, LL Newell, CE Thomsen, CJ Gold, SR Milner, JS Koss, MP Rosswork, SG TI Childhood abuse and sexual revictimization in a female navy recruit sample SO JOURNAL OF TRAUMATIC STRESS LA English DT Article DE childhood abuse; revictimization; rape; sexual assault ID ALCOHOLISM SCREENING-TEST; NATIONAL SAMPLE; CRIMINAL VICTIMIZATION; DATING SITUATIONS; RISK-FACTORS; TEST MAST; WOMEN; ASSAULT; PREVALENCE; AGGRESSION AB To examine effects of childhood abuse on adult rape, 1,887 female Navy recruits were surveyed. Overall 35% of recnrits had been raped and 57% had experienced childhood physical abuse (CPA) and/or childhood sexual abuse (CSA). Controlling for CPA, rape was significantly (4.8 times) more likely among women Mho had experienced CSA than among women who had not. III contrast, CPA (controlling for CSA) was unrelated to likelihood of adult rape. Alcohol problems and number of sex partners Mere examined as mediators. Although both variables predicted rape, their effects were independent of the effects of CSA. Finally despite ethnic group differences in the prevalence of victimization, the predictors of rape did not differ significantly across ethnic groups. C1 USN, Hlth Res Ctr, Dept Operat Res, San Diego, CA 92186 USA. No Illinois Univ, Dept Psychol, De Kalb, IL 60115 USA. Univ Arizona, Tucson, AZ 85721 USA. Bureau Naval Personnel, Family Advocacy Program, Washington, DC USA. RP Merrill, LL (reprint author), USN, Hlth Res Ctr, Dept Operat Res, San Diego, CA 92186 USA. NR 40 TC 108 Z9 109 U1 2 U2 5 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0894-9867 J9 J TRAUMA STRESS JI J. Trauma Stress PD APR PY 1999 VL 12 IS 2 BP 211 EP 225 DI 10.1023/A:1024789723779 PG 15 WC Psychology, Clinical; Psychiatry SC Psychology; Psychiatry GA 205YC UT WOS:000080847600001 PM 10378162 ER PT J AU Tuncer, IH Weber, S Sanz, W AF Tuncer, IH Weber, S Sanz, W TI Investigation of periodic boundary conditions in multipassage cascade flows using overset grids SO JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME LA English DT Article ID UNSTEADY AB A Navier-Stokes solutions method with overset grids is applied to unsteady multipassage cascade flows, and the unsteady blade loadings are compared against the single-passage solutions with the direct store interblade boundary condition. In the overset grid solutions, the multipassage domain is discretized with O-type grids around each blade and a rectangular background grid. Blade grids are allowed to move in time relative to the background grid as prescribed by the oscillatory plunging motion. The overset grid method uses a simple, robust numerical algorithm to localize moving intergrid boundary: points and to interpolate solution variables across grids. Computational results are presented for two and four-passage, subsonic and transonic flows through a turbine and a compressor cascade. The overset grid solutions over the multipassage periodic domains agree well with the single-passage solutions and the experimental data. It is concluded that the time linearization error introduced by the direct store approach is negligible in the range of flow conditions studied. C1 USN, Postgrad Sch, Dept Aeronaut, Monterey, CA 93943 USA. BMW Rolls Royce Gmbh, Aeroengines, Dahlewitz, Germany. Graz Tech Univ, Inst Turbomaschinen, A-8010 Graz, Austria. RP Tuncer, IH (reprint author), USN, Postgrad Sch, Dept Aeronaut, Monterey, CA 93943 USA. NR 17 TC 4 Z9 4 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0889-504X J9 J TURBOMACH JI J. Turbomach.-Trans. ASME PD APR PY 1999 VL 121 IS 2 BP 341 EP 347 PG 7 WC Engineering, Mechanical SC Engineering GA 189XF UT WOS:000079930900022 ER PT J AU Driscoll, TJ AF Driscoll, TJ TI Persistent strep SO LABORATORY MEDICINE LA English DT Letter C1 USN, Med Ctr, Dept Microbiol, San Diego, CA 92152 USA. RP Driscoll, TJ (reprint author), USN, Med Ctr, Dept Microbiol, San Diego, CA 92152 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC CLIN PATHOLOGISTS PI CHICAGO PA 2100 W HARRISON ST, CHICAGO, IL 60612 USA SN 0007-5027 J9 LAB MED JI Lab. Med. PD APR PY 1999 VL 30 IS 4 BP 227 EP 227 PG 1 WC Medical Laboratory Technology SC Medical Laboratory Technology GA 181LN UT WOS:000079443000009 ER PT J AU Mackney, MDA Ross, CTF AF Mackney, MDA Ross, CTF TI Preliminary ship design using one- and two-dimensional models SO MARINE TECHNOLOGY AND SNAME NEWS LA English DT Article AB Computational studies of hull-superstructure interaction were carried out using one-, two-and three-dimensional finite element analyses. Simplification of the original three-dimensional cases to one- and two-dimensional ones was undertaken to reduce the data preparation and computer solution times in an extensive parametric study. Both the one- and two-dimensional models were evaluated from numerical and experimental studies of the three-dimensional arrangements of hull and superstructure. One-dimensional analysis used a simple beam finite element with appropriately changed sections properties at stations where superstructures existed. Two-dimensional analysis used a four node, first order quadrilateral, isoparametric plane elasticity finite element, with a corresponding increase in the grid domain where the superstructure existed, Changes in the thickness property reflected deck stiffness. This model was essentially a multi-flanged beam with the shear webs representing the hull and superstructure sides, and the flanges representing the decks. One-dimensional models consistently and uniformly underestimated the three-dimensional behaviour, but were fast to create and run. Two-dimensional models were also consistent in their assessment, and considerably closer in predicting the actual behaviours. These models took longer to create than the one-dimensional, but ran in very much less time than the refined three-dimensional finite element models. parametric insights were accomplished quickly and effectively with the simplest model and processor, but two-dimensional analyses achieved closer absolute measure of the displacement behaviours. Although only static analysis with simple loading and support conditions were presented, it is believed that similar benefits would be found for other loadings and support conditions. Other engineering components and structures may benefit from similarly judged simplification using one- and two-dimensional models to reduce the time and cost of preliminary design. C1 USN Acad, Div Engn & Weapons, Annapolis, MD 21402 USA. RP Mackney, MDA (reprint author), USN Acad, Div Engn & Weapons, Annapolis, MD 21402 USA. NR 4 TC 4 Z9 4 U1 0 U2 0 PU SOC NAVAL ARCH MARINE ENG PI JERSEY CITY PA 601 PAVONIA AVENUE, JERSEY CITY, NJ 07306 USA SN 0025-3316 J9 MAR TECHNOL SNAME N JI Mar. Technol. Sname News PD APR PY 1999 VL 36 IS 2 BP 102 EP 111 PG 10 WC Engineering, Ocean; Oceanography SC Engineering; Oceanography GA 416BJ UT WOS:000167759200007 ER PT J AU Michael, TS AF Michael, TS TI Sphere of influence graphs in general metric spaces SO MATHEMATICAL AND COMPUTER MODELLING LA English DT Article DE proximity graphs; intersection graphs ID OF-INFLUENCE GRAPHS; SIZE AB Let X = {X-1,..., X-n} be a set of points in a metric space (n greater than or equal to 2). Let r(i) denote the minimum distance between X-i and the other points in X. The sphere of influence at X-i is the open ball with center X-i and radius r(i). The sphere of influence graph has vertex set X with an edge joining a pair of distinct vertices provided the corresponding spheres of influence intersect. This proximity graph was introduced by Toussaint to model computer vision and pattern recognition problems in the Euclidean plane. We discuss the abstract properties of sphere of influence graphs in general metric spaces with emphasis on normed linear spaces. Our work generalizes and simplifies some theorems in the literature on sphere of influence graphs and lays the groundwork for future work. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 USN Acad, Dept Math, Annapolis, MD 21402 USA. Univ Nevada, Dept Math, Reno, NV 89557 USA. RP Michael, TS (reprint author), USN Acad, Dept Math, Annapolis, MD 21402 USA. NR 18 TC 9 Z9 10 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0895-7177 J9 MATH COMPUT MODEL JI Math. Comput. Model. PD APR PY 1999 VL 29 IS 7 BP 45 EP 53 DI 10.1016/S0895-7177(99)00061-8 PG 9 WC Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering; Mathematics, Applied SC Computer Science; Mathematics GA 194EX UT WOS:000080180100004 ER PT J AU Albares, DJ Sun, CK Nguyen, R Chang, CT AF Albares, DJ Sun, CK Nguyen, R Chang, CT TI Optically controlled RF switches combat EMI SO MICROWAVES & RF LA English DT Article AB ACCURATE and reliable control of microwave switches is critical in any environment dominated by electromagnetic interference (EMI), Sites such as communication-antenna arrays, microwave repeaters, and military platforms are constantly exposed to high-level emissions of EMI. Electrical-control signals can be compromised under such conditions. However, under optical control, microwave switches can be operated reliably even in the most-hostile EMI environments. C1 USN, Space & Warfare Syst Ctr, San Diego, CA 92152 USA. RP Albares, DJ (reprint author), USN, Space & Warfare Syst Ctr, San Diego, CA 92152 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU PENTON MEDIA, INC PI CLEVELAND PA 1100 SUPERIOR AVE, CLEVELAND, OH 44114-2543 USA SN 0745-2993 J9 MICROWAVES RF JI Microw. RF PD APR PY 1999 VL 38 IS 4 BP 86 EP + PG 7 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 187QQ UT WOS:000079798600023 ER PT J AU Reineck, C AF Reineck, C TI The federal nursing service award - Individual readiness in nursing SO MILITARY MEDICINE LA English DT Article AB Individual readiness is critical for effective nursing in deployed environments. Although readiness is routinely tracked and reported, a study of its complexity among federal nurses was needed. An inductive research approach clarified the concept of individual readiness. Representing a broad range of deployment experience, focus group members developed a definition of the concept and identified six components: clinical competency; operational competency; survival skills; personal/psychosocial/physical readiness; leadership and administrative support; and group integration and identification. The findings form an overdue conceptual basis for future measurement of this important dimension of federal nursing. RP Reineck, C (reprint author), USN, Med Command, Ft Sam Houston, TX 78234 USA. NR 11 TC 11 Z9 12 U1 0 U2 1 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD APR PY 1999 VL 164 IS 4 BP 251 EP 255 PG 5 WC Medicine, General & Internal SC General & Internal Medicine GA 185JD UT WOS:000079664600004 PM 10226449 ER PT J AU Brooks, DM Hand, WR AF Brooks, DM Hand, WR TI A cost analysis: General endotracheal versus regional versus monitored anesthesia care SO MILITARY MEDICINE LA English DT Article ID DRUGS; TRIAL AB A prospective study was conducted to compare the total cost of all consumable products used to perform a general endotracheal anesthetic (GETA), a regional anesthetic, and a monitored anesthetic (MAC). For 1 month, providers completed a survey for each anesthetic rendered identifying type and quantity of consumables used. The mean cost of each type of anesthetic was identified. Analysis of variance was conducted using SPSS (version 7.5.1) to compare the mean costs of the three groups. Of 936 anesthetics performed, 536 surveys were returned (57%). The breakdown by type was GETA, 60% (N = 319); regional, 35% (N = 189); and MAC, 5% (N = 28). The mean cost per case type was GETA, $61.74; regional, $34.99; and MAC, $26.27. The cost of rendering a GETA was significantly greater (p < 0.0005) than that of either regional or MAC. Clinical practice guidelines were established to address areas in which cost savings could be realized and were provided to all anesthesia practitioners to assist in providing the safest and most cost-effective method of rendering an anesthetic. C1 USN, Nurse Corps Anesthesia Program, Bethesda, MD 20084 USA. RP Brooks, DM (reprint author), USN, Nurse Corps Anesthesia Program, Bethesda, MD 20084 USA. NR 10 TC 3 Z9 3 U1 0 U2 0 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD APR PY 1999 VL 164 IS 4 BP 303 EP 305 PG 3 WC Medicine, General & Internal SC General & Internal Medicine GA 185JD UT WOS:000079664600016 PM 10226461 ER PT J AU O'Boyle, JD Magann, EF Waxman, E Martin, JN AF O'Boyle, JD Magann, EF Waxman, E Martin, JN TI Dexamethasone-facilitated postponement of delivery of an extremely preterm pregnancy complicated by the syndrome of hemolysis, elevated liver enzymes, and low platelets SO MILITARY MEDICINE LA English DT Article ID HELLP-SYNDROME; SEVERE PREECLAMPSIA; CORTICOSTEROIDS; LUNG; PROGRESSION; GESTATION; THERAPY; DISEASE; IMPACT AB Objective: Patients with severe preeclampsia and the syndrome of hemolysis, elevated liver enzymes, and low platelets (HELLP syndrome) are at increased risk for perinatal and maternal morbidity, especially in very preterm gestations. When this condition affects a pregnancy on the cusp of viability, a therapeutic intervention to prolong gestation without undue risk to the mother or fetus could be beneficial. Method: A single case report and review of the literature. Result: We report a patient with HELLP syndrome in whom antenatal administration of high-dose dexamethasone helped achieve disease stabilization and delivery postponement for 9 days of a very preterm fetus estimated to weigh less than 600 g, Both mother and infant did well postpartum. Conclusion: Administration of antenatal high-dose dexamethasone can be used in carefully selected preterm patients with HELLP syndrome to delay delivery while in utero fetal maturation is accelerated and the maternal condition is optimized. This can be beneficial in carefully selected pregnancies without apparent adverse maternal or perinatal impact. C1 USN, Med Ctr, Dept Obstet & Gynecol, San Diego, CA 92134 USA. RP O'Boyle, JD (reprint author), USN, Med Ctr, Dept Obstet & Gynecol, San Diego, CA 92134 USA. NR 12 TC 9 Z9 11 U1 0 U2 1 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD APR PY 1999 VL 164 IS 4 BP 316 EP 318 PG 3 WC Medicine, General & Internal SC General & Internal Medicine GA 185JD UT WOS:000079664600019 PM 10226464 ER PT J AU Businger, MP Read, RR AF Businger, MP Read, RR TI Identification of demand patterns for selective processing: a case study SO OMEGA-INTERNATIONAL JOURNAL OF MANAGEMENT SCIENCE LA English DT Article DE Box-Jenkins; statistics; time series; case study ID FORECASTING METHODS; ERROR MEASURES; TIME-SERIES AB A basic function in the proper management of repair part inventories is the anticipation of demand. The US Navy maintains a database of univariate demand data for its repair part inventories using a quarterly time interval and a limited number of periods. Historically, the exponential smoothing procedure has been used for demand forecasting. This method is simple and robust, but it does not make use of any characteristics of the entire time series such as trend, cycles, presence of outliers or demand clustering. Sharper information may be available with the use of the Box-Jenkins system. Not all repair parts can capitalize on this and there is a problem in identifying those that do. Moreover the number of parts is quite large and the speed of identification is an issue. This paper addresses this problem. The research begins with the development of several simple, robust and dimensionless time series features. These are used to predict the suitability of Box-Jenkins (ARIMA) modeling. Two predictive models are considered: classical regression and a modern expert-system statistical package, ModelQuest(TM): Their Strengths and weaknesses are compared. The result of either is a computationally simple means for determining which repair parts time series may benefit from the Box-Jenkins methodology for purposes of inventory management. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 USN, Postgrad Sch, Dept Operat Res, Code OR RE, Monterey, CA 93943 USA. RP Read, RR (reprint author), USN, Postgrad Sch, Dept Operat Res, Code OR RE, Monterey, CA 93943 USA. NR 26 TC 3 Z9 3 U1 1 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0305-0483 J9 OMEGA-INT J MANAGE S JI Omega-Int. J. Manage. Sci. PD APR PY 1999 VL 27 IS 2 BP 189 EP 200 DI 10.1016/S0305-0483(98)00039-5 PG 12 WC Management; Operations Research & Management Science SC Business & Economics; Operations Research & Management Science GA 176MR UT WOS:000079155800005 ER PT J AU Ashton, EA AF Ashton, EA TI Multialgorithm solution for automated multispectral target detection SO OPTICAL ENGINEERING LA English DT Article DE multispectral; target detection; clustering; anomaly; hyperspectral ID TEXTURED IMAGES; SEGMENTATION; ALGORITHM; DESIGN AB A solution to the problem of automated detection of targets with unknown spectral properties in multispectral imagery is presented that makes use of three background characterization and suppression algorithms in series. The first, parametric Bayesian clustering, is used to accurately characterize individual elements of the background scene. The second, background suppression filtering, eliminates those dimensions of multispectral space containing the majority of background energy. Finally, a multidimensional extension of the well-known Linde-Buzo-Gray (LBG) clustering algorithm is used to characterize what remains of the background and extract any anomalous target signatures. The results of this process are compared to spectral decorrelation (RX) filtering alone, LEG clustering alone, and RX filtering in combination with background suppression filtering. The process presented is shown to be significantly superior to each of these algorithm combinations. (C) 1999 Society of Photo-Optical Instrumentation Engineers. [S0091-3286(99)00504-8]. C1 USN, Res Lab, Fairfax, VA 22030 USA. RP Ashton, EA (reprint author), USN, Res Lab, Code 5621,5302 Hampton Forest Way, Fairfax, VA 22030 USA. NR 19 TC 9 Z9 9 U1 0 U2 1 PU SPIE-INT SOCIETY OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, BELLINGHAM, WA 98225 USA SN 0091-3286 J9 OPT ENG JI Opt. Eng. PD APR PY 1999 VL 38 IS 4 BP 717 EP 724 DI 10.1117/1.602115 PG 8 WC Optics SC Optics GA 185HR UT WOS:000079663400021 ER PT J AU Kuhn, CJJ Lassen, CLF AF Kuhn, CJJ Lassen, CLF TI Acute upper airway obstruction after recreational inhalation of a hydrofluorocarbon propellant SO OTOLARYNGOLOGY-HEAD AND NECK SURGERY LA English DT Article; Proceedings Paper CT 100th Annual Meeting of the American-Academy-of-Otolaryngology-Head-and-Neck-Surgery CY SEP 29-OCT 02, 1996 CL WASHINGTON, D.C. SP Amer Acad Otolaryngol Head & Neck Surg ID TOLUENE ABUSE; FROSTBITE; EXPOSURE; PROPANE C1 USN, Med Ctr, Dept Otolaryngol Head & Neck Surg, NMCP, Portsmouth, VA 23708 USA. RP Kuhn, CJJ (reprint author), USN, Med Ctr, Dept Otolaryngol Head & Neck Surg, NMCP, Portsmouth, VA 23708 USA. NR 18 TC 0 Z9 0 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0194-5998 J9 OTOLARYNG HEAD NECK JI Otolaryngol. Head Neck Surg. PD APR PY 1999 VL 120 IS 4 BP 587 EP 590 PG 4 WC Otorhinolaryngology; Surgery SC Otorhinolaryngology; Surgery GA 184DF UT WOS:000079594100037 ER PT J AU Voigt, RG Dickerson, CL Childers, DO Reynolds, AM Rodriguez, DL Brown, FR AF Voigt, RG Dickerson, CL Childers, DO Reynolds, AM Rodriguez, DL Brown, FR TI Early pediatric neurodevelopmental profile and laboratory workup of children with autism and pervasive developmental disorder not otherwise specified (PDD-NOS) SO PEDIATRIC RESEARCH LA English DT Meeting Abstract C1 Mayo Clin, Dept Pediat & Adolescent Med, Rochester, MN USA. Baylor Coll Med, Dept Pediat, Houston, TX 77030 USA. Naval Hosp, Dept Pediat, Camp Lejeune, NC USA. Ctr Child Study, Sect Neurodev Pediat, Ft Worth, TX USA. NR 0 TC 0 Z9 0 U1 1 U2 3 PU INT PEDIATRIC RESEARCH FOUNDATION, INC PI BALTIMORE PA 351 WEST CAMDEN ST, BALTIMORE, MD 21201-2436 USA SN 0031-3998 J9 PEDIATR RES JI Pediatr. Res. PD APR PY 1999 VL 45 IS 4 MA 780 BP 134A EP 134A PN 2 PG 1 WC Pediatrics SC Pediatrics GA 182AQ UT WOS:000079476700781 ER PT J AU Wierzba, TF Hall, E Abu-Elvazeed, RR Savarino, SJ Frenck, RW Rao, MR Naticy, AB Morsy, BZ Clemens, JD AF Wierzba, TF Hall, E Abu-Elvazeed, RR Savarino, SJ Frenck, RW Rao, MR Naticy, AB Morsy, BZ Clemens, JD TI Human milk antibody titers to enterotoxigenic Escherichia coli (ETEC) antigens among 118 lactating Egyptian women SO PEDIATRIC RESEARCH LA English DT Meeting Abstract C1 USN, Med Res Unit 3, Res Sci Dept, Cairo, Egypt. NICHHD, Bethesda, MD 20892 USA. Minist Hlth & Populat, Hlth Serv, Abu Homos, Beheria, Egypt. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INT PEDIATRIC RESEARCH FOUNDATION, INC PI BALTIMORE PA 351 WEST CAMDEN ST, BALTIMORE, MD 21201-2436 USA SN 0031-3998 J9 PEDIATR RES JI Pediatr. Res. PD APR PY 1999 VL 45 IS 4 MA 1040 BP 178A EP 178A DI 10.1203/00006450-199904020-01057 PN 2 PG 1 WC Pediatrics SC Pediatrics GA 182AQ UT WOS:000079476701041 ER PT J AU Broughton, JQ Mehl, MJ AF Broughton, JQ Mehl, MJ TI Transferable potential for carbon without angular terms SO PHYSICAL REVIEW B LA English DT Article ID INTERATOMIC FORCE-FIELDS; EMBEDDED-ATOM METHOD; SILICON STRUCTURAL ENERGIES; ELECTRONIC-PROPERTIES; CONSTANT MODEL; HIGH-PRESSURE; BULK PHASES; DIAMOND; C-60; METALS AB A simple transferable potential for carbon is developed for use in atomistic simulation. It describes all the phases of carbon, from the close packed, such as face centered cubic, to the open systems, such as diamond cubic, graphite, and even linear chains. The parameters are fit to a total-energy local-density functional theory database augmented by the known cohesive energies of diamond and graphite. Further, structures such as simple molecules, not in the database, are well described. For example, it predicts that odd number of atom molecules form chains whereas even atom number molecules form rings. The diamond cubic and graphitic structures are dynamically stable. The formalism also allows for interaction with an external electric field. Further, it can be generalized to other covalent systems as well as mid-d-block elements. [S0163-1829(99)00814-0]. C1 USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. Yale Univ, Sch Management, New Haven, CT 06520 USA. RP Broughton, JQ (reprint author), USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. RI Mehl, Michael/H-8814-2016 NR 52 TC 11 Z9 12 U1 2 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1999 VL 59 IS 14 BP 9259 EP 9270 DI 10.1103/PhysRevB.59.9259 PG 12 WC Physics, Condensed Matter SC Physics GA 186WT UT WOS:000079754300030 ER PT J AU Kammer, CS Young, CC Niedfeldt, MW AF Kammer, CS Young, CC Niedfeldt, MW TI Swimming injuries and illnesses SO PHYSICIAN AND SPORTSMEDICINE LA English DT Article ID COMPETITIVE SWIMMERS; SHOULDER; PAIN; STRENGTH; MUSCLE; LAXITY; ELITE AB Swimming has a distinct profile of injuries and medical conditions. Common problems seen among swimmers include 'swimmer's shoulder,' an overuse injury that causes inflammation of the supraspinatus and/or the biceps tendon; overuse injuries of the elbow, knee, ankle, and back; medical conditions such as asthma, folliculitis, and otitis externa; and problems associated with overtraining. Swimmers are more likely to comply with treatment plans that minimize time spent out of the water. Prevention and treatment of musculoskeletal injuries often focus on proper stroke mechanics. C1 Med Coll Wisconsin, Ctr Sports Med, Dept Community & Family Med, Milwaukee, WI 53226 USA. Med Coll Wisconsin, Dept Orthopaed Surg, Milwaukee, WI 53226 USA. Iowa Lutheran Hosp, Des Moines, IA USA. USN, Reserve, Washington, DC 20350 USA. RP Young, CC (reprint author), Med Coll Wisconsin, Ctr Sports Med, Dept Community & Family Med, 9200 W Wisconsin Ave,Box 26099, Milwaukee, WI 53226 USA. NR 27 TC 13 Z9 14 U1 0 U2 11 PU MCGRAW HILL HEALTHCARE PUBLICATIONS PI MINNEAPOLIS PA 4530 WEST 77TH ST, MINNEAPOLIS, MN 55435-5000 USA SN 0091-3847 J9 PHYSICIAN SPORTSMED JI Physician Sportsmed. PD APR PY 1999 VL 27 IS 4 BP 51 EP + PG 8 WC Primary Health Care; Orthopedics; Sport Sciences SC General & Internal Medicine; Orthopedics; Sport Sciences GA 182UE UT WOS:000079515900011 PM 20086710 ER PT J AU Sanford, TWL Mock, RC Nash, TJ Whitney, KG Pulsifer, PE Apruzese, JP Mosher, D Peterson, DL Haines, MG AF Sanford, TWL Mock, RC Nash, TJ Whitney, KG Pulsifer, PE Apruzese, JP Mosher, D Peterson, DL Haines, MG TI Systematic trends in x-ray emission characteristics of variable-wire-number, fixed-mass, aluminum-array, Z-pinch implosions SO PHYSICS OF PLASMAS LA English DT Article ID SIMILAR ATOMIC NUMBERS; HIGH-POWER; PLASMAS; DIAGNOSTICS; ELEMENTS; SATURN AB Increasing the number of wires an order of magnitude from 10 to almost 200 while simultaneously fixing the total wire mass in annular aluminum-wire-array Z-pinch implosions on the 20 TW Saturn generator [Proceedings of the 6th International IEEE Pulsed Power Conference (Institute of Electrical and Electronics Engineers, Piscataway, NJ, 1987), p. 310] demonstrates two separate power-law trends in the measured x-ray characteristics as a function of the initial interwire gap (g). These trends are approximately independent of the array radius. When g decreases from similar to 6 to 0.4 mm, the peak total radiated power increases by a factor of 20 and the total energy by a factor of 2. There is a more rapid increase in peak power and energy radiated as g decreases for gaps greater than;2 mm. This increase is related to a measured decrease in precursor plasma and to a calculated decreased sensitivity of the implosion to azimuthal asymmetries that occurs when individual wire plasmas begin to merge following their vaporization. The substantial increase in power arises from an inferred increase in plasma compression and can be correlated with an almost linear reduction in the calculated effective thickness of the plasma annulus near stagnation as g decreases. (C) 1999 American Institute of Physics. [S1070-664X(99)00404-8]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. USN, Res Lab, Radiat Hydrodynam Branch, Washington, DC 20375 USA. USN, Res Lab, Pulsed Power Phys Branch, Washington, DC 20375 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BZ, England. RP Sanford, TWL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 54 TC 31 Z9 39 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD APR PY 1999 VL 6 IS 4 BP 1270 EP 1293 DI 10.1063/1.873370 PG 24 WC Physics, Fluids & Plasmas SC Physics GA 179WY UT WOS:000079354100024 ER PT J AU Salgia, ADT Kosnik, SD AF Salgia, ADT Kosnik, SD TI When acetaminophen use becomes toxic - Treating acute accidental and intentional overdose SO POSTGRADUATE MEDICINE LA English DT Article ID HEPATOTOXICITY AB Whether accidental or intentional, acetaminophen poisoning is not uncommon; in fact, it is the most common drug-induced cause of liver failure. When hepatic glutathione is depleted, the toxic metabolite NAPQI fails to be conjugated and causes hepatic injury. At risk are chronic alcoholics, binge drinkers, patients taking medications that induce the P-450 isoenzyme system, and those with concomitant liver disease. The four phases that make up the clinical course of acetaminophen poisoning distinguish signs, symptoms, and laboratory values according to severity. In diagnosing acetaminophen toxicity, adequate history taking and serial measurements of acetaminophen level are essential. Treatment is rooted in three goals: decreasing the absorption of acetaminophen using activated charcoal, replacing hepatic glutathione using acetylcysteine, and supportive care in the case of hepatic failure. The prognosis depends on the amound ingested and the time of presentation after ingestion. C1 USN, Emerald Isle, NC 28594 USA. RP Salgia, ADT (reprint author), USN, 316 Loblolly St, Emerald Isle, NC 28594 USA. NR 12 TC 8 Z9 8 U1 1 U2 3 PU MCGRAW HILL HEALTHCARE PUBLICATIONS PI MINNEAPOLIS PA 4530 WEST 77TH ST, MINNEAPOLIS, MN 55435-5000 USA SN 0032-5481 J9 POSTGRAD MED JI Postgrad. Med. PD APR PY 1999 VL 105 IS 4 BP 81 EP + PG 6 WC Medicine, General & Internal SC General & Internal Medicine GA 184EA UT WOS:000079596300008 PM 10223088 ER PT J AU Carr, W Roskos-Ewoldsen, B AF Carr, W Roskos-Ewoldsen, B TI Spatial orientation by mental transformation SO PSYCHOLOGICAL RESEARCH-PSYCHOLOGISCHE FORSCHUNG LA English DT Article ID ROTATED NATURAL OBJECTS; VISUAL IMAGES; MEMORY; REPRESENTATIONS; DISTORTIONS; MODELS; MAPS; IDENTIFICATION; COMPREHENSION; INFORMATION AB Across three experiments, college students read narratives describing two-dimensional horizontal, sagittal, or coronal environments, each with seven objects in surrounding directions (at 45 degrees angles). Then they responded from memory to questions about which objects were in specific directions. The distributions of error rates and response times were compared with distributions predicted by a mental transformation model and two verbal-spatial decoding and retrieval models. The data fit the predictions of a modified mental transformation model (mental transformation plus 180 degrees exception) better than the predictions of either verbal-spatial model. This was true even though the environment was presented narratively rather than perceptually, and it was true for both the vertical planes in addition to the more typical horizontal plane. C1 USN, Submarine Med Res Lab, Submarine Base New London, Groton, CT 06349 USA. Univ Alabama, Dept Psychol, Tuscaloosa, AL 35487 USA. RP Carr, W (reprint author), USN, Submarine Med Res Lab, Submarine Base New London, Box 900, Groton, CT 06349 USA. RI Roskos-Ewoldsen, Beverly/B-6585-2008 NR 50 TC 4 Z9 4 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0340-0727 J9 PSYCHOL RES-PSYCH FO JI Psychol. Res.-Psychol. Forsch. PD APR PY 1999 VL 62 IS 1 BP 36 EP 47 DI 10.1007/s004260050038 PG 12 WC Psychology, Experimental SC Psychology GA 195XA UT WOS:000080276400003 ER PT J AU Pogozelski, WK Xapsos, MA Blakely, WF AF Pogozelski, WK Xapsos, MA Blakely, WF TI Quantitative assessment of the contribution of clustered damage to DNA double-strand breaks induced by Co-60 gamma rays and fission neutrons SO RADIATION RESEARCH LA English DT Article ID IRRADIATED PLASMID DNA; SINGLE-STRAND; SCAVENGER CONCENTRATION; AQUEOUS-SOLUTIONS; OH RADICALS; SV40 DNA; RADIATION; YIELD; INDUCTION; MECHANISMS AB The induction of DNA strand breaks by fission neutrons was studied in aqueous plasmid (pBR322) DNA under aerobic conditions for a wide range of hydroxyl radical ((OH)-O-.) scavenger concentrations and was compared to the induction of strand breaks by Co-60 gamma rays. Strand breaks were measured using agarose gel electrophoresis coupled with sensitive P-32-based phosphor imaging. Yields are reported for DNA single-strand breaks (SSBs) and double-strand breaks formed linearly with dose (alpha DSBs), The fraction of alpha DSBs that were dependent on the multiply damaged site (MDS) or clustered damage mechanism was also calculated using a model. G values for SSBs and alpha DSBs declined with increasing (OH)-O-. scavenging capacity. However, with increasing (OH)-O-. scavenging capacities, the decrease in yields of strand breaks for fission neutrons was not as pronounced as for gamma rays. The percentage of alpha DSBs for gamma rays was dependent on (OH)-O-. scavenging capacity, appearing negligible at low scavenging capacities but increasing at higher scavenging capacities. In contrast, fission neutrons induced high percentages of alpha DSBs that were approximately independent of (OH)-O-. scavenging capacity. The levels of alpha DSBs formed by the MDS mechanism after exposure to fission neutrons are consistent with the expected distinctive features of high-LET energy deposition events and track structure, The results also confirm observations made by others that even for low-LET radiation, the MDS mechanism contributes significantly to DNA damage at cell-like scavenging conditions. (C) 1999 by Radiation Research Society. C1 USN, Res Lab, Radiat Effects Branch, Washington, DC 20375 USA. SUNY Geneseo, Geneseo, NY 14454 USA. Armed Forces Radiobiol Res Inst, Dept Appl Cellular Radiobiol, Bethesda, MD 20889 USA. RP Pogozelski, WK (reprint author), USN, Res Lab, Radiat Effects Branch, Washington, DC 20375 USA. NR 38 TC 9 Z9 10 U1 0 U2 0 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD APR PY 1999 VL 151 IS 4 BP 442 EP 448 DI 10.2307/3579831 PG 7 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 181MY UT WOS:000079446100009 PM 10190496 ER PT J AU Viera, AJ Yates, SW AF Viera, AJ Yates, SW TI Toxic ingestion of gamma-hydroxybutyric acid SO SOUTHERN MEDICAL JOURNAL LA English DT Article ID INTOXICATION; OVERDOSE; TALE AB Gamma-hydroxybutyric acid (GHB) has become a popular new drug of abuse. Its effects include euphoria and disinhibition, Recently, several cases hale been reported in the literature of Life-threatening or lethal ingestions, We report the case of a 17-year-old male who became unresponsive after taking GHB, Gamma-hydroxybutyric acid is used outside the United States to treat narcolepsy. In the past, it was touted as a muscle-bulking aid and was taken by body-builders, It has also been implicated as a drug involved in "date-rapes." Patients who ingest excessive GHB have a markedly altered level of consciousness, as did the patient in this illustrative case. Neostigmine and physostigmine show promise as potential reversal agents. Gamma-hydroxybutyric acid overdose should be considered in any patient with altered mental status and a history of recreational drug abuse. C1 USN Hosp, Dept Family Practice, Daytona Beach, FL 32114 USA. USN Hosp, Dept Internal Med, Daytona Beach, FL 32114 USA. RP Viera, AJ (reprint author), USN Hosp, Dept Family Practice, 2080 Child St, Daytona Beach, FL 32114 USA. OI Yates, Scott/0000-0002-5197-0686 NR 11 TC 19 Z9 19 U1 0 U2 2 PU SOUTHERN MEDICAL ASSN PI BIRMINGHAM PA 35 LAKESHORE DR PO BOX 190088, BIRMINGHAM, AL 35219 USA SN 0038-4348 J9 SOUTHERN MED J JI South.Med.J. PD APR PY 1999 VL 92 IS 4 BP 404 EP 405 PG 2 WC Medicine, General & Internal SC General & Internal Medicine GA 186DF UT WOS:000079711100009 PM 10219359 ER PT J AU Rodriguez, MI Ash, K Foley, RW Liston, W AF Rodriguez, MI Ash, K Foley, RW Liston, W TI Pericardio peritoneal window - Laparoscopic approach SO SURGICAL ENDOSCOPY-ULTRASOUND AND INTERVENTIONAL TECHNIQUES LA English DT Article DE laparoscopy; pericardio-peritoneal window ID DISEASE AB Transdiaphragmatic approach to the pericarium through the use of the laparoscope is a safe and rapid way to obtain biopsy of the pericardium and create a window. No drainage tubes are needed: pericardial fluid is absorbed by the peritoneum; there is no need for double lumen tubes for one lung ventilation; and the laparoscopy incisions are small and almost painless. C1 USN, Med Ctr, Dept Gen Surg, Div Thorac Surg, Portsmouth, VA 23708 USA. RP Rodriguez, MI (reprint author), USN, Med Ctr, Dept Gen Surg, Div Thorac Surg, 620 John Paul Jones Circle, Portsmouth, VA 23708 USA. NR 8 TC 11 Z9 11 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0930-2794 J9 SURG ENDOSC-ULTRAS JI Surg. Endosc.-Ultrason. Interv. Tech. PD APR PY 1999 VL 13 IS 4 BP 409 EP 411 DI 10.1007/s004649901001 PG 3 WC Surgery SC Surgery GA 179WE UT WOS:000079352300022 PM 10094759 ER PT J AU Liberman, MA Greason, K AF Liberman, MA Greason, K TI Residency training in advanced laparoscopic surgery: How are we doing? SO SURGICAL LAPAROSCOPY ENDOSCOPY & PERCUTANEOUS TECHNIQUES LA English DT Article DE laparoscopy; internship and residency; training support; education/medical/graduate ID SURGICAL RESIDENTS; CHOLECYSTECTOMY; COMPLICATIONS AB Despite the phenomenal growth of laparoscopic surgery since 1987, surgical residency training programs are failing to train residents in advanced laparoscopic procedures. Data were obtained from the operative registry maintained by the Department of General Surgery, Naval Medical Center San Diego and included all operations performed during the course of a 5-year general surgery residency by residents graduating in 1992(group1) and those graduating in 1996 (group 2). Each of the group 1 residents averaged 18 laparoscopic cholecystectomies and 68 open cholecystectomies, whereas the group 2 residents averaged 95 laparoscopic cholecystectomies and 18 open cholecystectomies. Group 1 residents averaged <1 advanced laparoscopic procedure during their residency, whereas group 2 residents averaged 46. Although there was no significant difference in total open cases between groups 1 and 2 (1,233 vs 1,197 respectively; p > 0.99), group 2 performed a significantly greater proportion of laparoscopic cases (12% vs 1%; p < 0.001). The teaching of advanced laparoscopic procedures can and should be incorporated into the surgical residency. C1 USN, Dept Gen Surg, Ctr Med, San Diego, CA 92134 USA. RP Liberman, MA (reprint author), USN, Dept Gen Surg, Ctr Med, San Diego, CA 92134 USA. NR 14 TC 10 Z9 10 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1051-7200 J9 SURG LAPARO ENDO PER PD APR PY 1999 VL 9 IS 2 BP 87 EP 90 DI 10.1097/00019509-199904000-00002 PG 4 WC Surgery SC Surgery GA 200GA UT WOS:000080530200002 PM 11757550 ER PT J AU Westphal, DL Holt, TR Chang, SW Baker, NL Hogan, TF Brody, LR Godfrey, RA Goerss, JS Cummings, JA Laws, DJ Hines, CW AF Westphal, DL Holt, TR Chang, SW Baker, NL Hogan, TF Brody, LR Godfrey, RA Goerss, JS Cummings, JA Laws, DJ Hines, CW TI Meteorological reanalyses for the study of Gulf War illnesses: Khamisiyah case study SO WEATHER AND FORECASTING LA English DT Article ID OPTIMUM INTERPOLATION; PREDICTION MODELS; FORECAST MODEL; NAVY; SYSTEM; SENSITIVITY; MESOSCALE; DESIGN AB The Marine Meteorology Division of the Naval Research Laboratory (NRL), assisted by the Fleet Numerical Meteorology and Oceanography Center, has performed global and mesoscale reanalyses to support the study of Gulf War illness. Realistic and quantitatively accurate atmospheric conditions are needed to drive dispersion models that can predict the transport and dispersion of chemical agents that may have affected U.S. and other coalition troops in the hours and days following the demolition of chemical weapons at Khamisiyah, Iraq, at approximately 1315 UTC 10 March 1991. The reanalysis was conducted with the navy's global and mesoscale analysis and prediction systems: the Navy Operational Global Atmospheric Prediction System and the NRL Coupled Ocean-Atmosphere Mesoscale Prediction System. A comprehensive set of observations has been collected and used in the reanalysis, including unclassified and declassified surface reports, ship and buoy reports, observations from pibal and rawinsonde, and retrievals from civilian and military satellites. The atmospheric conditions for the entire globe have been reconstructed using the global system at the effective spatial resolution of 0.75 degrees. The atmospheric conditions over southern Iraq, Kuwait, and northern Saudi Arabia have been reconstructed using the mesoscale system at the spatial resolutions of 45, 15, and 5 km. In addition to a baseline reanalysis, perturbation analyses were also performed to estimate the atmospheric sensitivity to observational error and analysis error. The results suggest that the reanalysis has bounded the variability and that the actual atmospheric conditions were unlikely to differ significantly from the reanalysis. The synoptic conditions at and after the time of the detonation were typical of the transitional period after a Shamal and controlled by eastward-propagating small-amplitude troughs and ridges. On the mesoscale, the conditions over the Tigris-Euphrates Valley were further modulated by the diurnal variation in the local circulations between land, the Persian Gulf, and the Zagros Mountains. The boundary layer winds at Khamisiyah were from NNW at the time of the detonation and shifted to WNW in the nocturnal boundary layer. On the second day, a strong high passed north of Khamisiyah and the winds strengthened and turned to the ESE. During the third day, the region was dominated by the approach and passage of a low pressure system and the associated front with the SE winds veering to NW. A transport model for passive scalars was used to illustrate the sensitivity to the reanalyzed fields of potential areas of contamination. Transport calculations based on various release scenario and reanalyzed meteorological conditions suggest that the mean path of the released chemical agents was southward from Khamisiyah initially, turning westward, and eventually northwestward during the 72-h period after the demolition. Precipitation amounts in the study area were negligible and unlikely to have an effect on the nerve agent. C1 USN, Res Lab, Monterey, CA 94943 USA. Fleet Numer Meteorol & Oceanog Ctr, Monterey, CA USA. RP Chang, SW (reprint author), USN, Res Lab, 7 Grace Hopper St,Stop 2, Monterey, CA 94943 USA. EM simon.chang@nrl.navy.mil NR 28 TC 8 Z9 8 U1 1 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0882-8156 J9 WEATHER FORECAST JI Weather Forecast. PD APR PY 1999 VL 14 IS 2 BP 215 EP 241 DI 10.1175/1520-0434(1999)014<0215:MRFTSO>2.0.CO;2 PG 27 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 187XH UT WOS:000079813400006 ER PT J AU Kester, DJ Brodbeck, CL Singer, IL Kyriakopoulos, A AF Kester, DJ Brodbeck, CL Singer, IL Kyriakopoulos, A TI Sliding wear behavior of diamond-like nanocomposite coatings SO SURFACE & COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 25th International Conference on Metallurgical Coatings and Thin Films CY APR 27-MAY 01, 1998 CL SAN DIEGO, CALIFORNIA SP Vacuum Met, Thin Film Div, AVS DE diamond-like nanocomposites; wear behavior ID CHEMICAL-VAPOR-DEPOSITION; CARBON COATINGS; TRIBOLOGY; FILMS AB Diamond-like nanocomposites (DLN) are a class of amorphous thin film material consisting of a diamond-like carbon (a-C:H) network and a glass-like a-Si:O network. The sliding wear behavior of 1-2-mu m-thick DLN coatings on Si was studied using WC and steel balls in ambient air (RH = 30-50%) at initially high contact stresses (0.8 GPa). The hardness of the DLN coatings, 9-17 GPa, was greater than that of steel (8 GPa) but less than that of WC (16 GPa). The friction coefficients for both couples were between 0.04 and 0.06, and the endurances were from 30000 to 200000 cycles. Despite the similarities, the wear behavior of the steel/DLN and WC/DLN couples differed: in the former, the steel balls wore, producing lower stresses but wider and deeper wear tracks; in the latter, the WC ball did not wear, and the wear tracks were narrower and wore uniformly. The latter wear behavior allowed wear rates for DLN to be determined. The wear of the DLN was measured at regular intervals during extended ball-on-disk testing. DLN was shown to wear at a constant rate, i.e. linearly with number of cycles, and to have wear factors in the range of 2 x 10(-8)-1.1 x 10(-6) mm(3) N-1 m(-1). (C) 1999 Elsevier Science S.A. All rights reserved. C1 Adv Refractory Technol Inc, Buffalo, NY 14207 USA. USN, Res Lab, Washington, DC 20375 USA. RP Kester, DJ (reprint author), Adv Refractory Technol Inc, 699 Hertel Ave, Buffalo, NY 14207 USA. NR 13 TC 35 Z9 35 U1 2 U2 6 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD MAR 31 PY 1999 VL 113 IS 3 BP 268 EP 273 DI 10.1016/S0257-8972(99)00003-1 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 187UZ UT WOS:000079807600010 ER PT J AU Blank, DA Loui, J AF Blank, DA Loui, J TI A coding error elimination procedure for verifying finite element programs with forced and natural boundary conditions SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING LA English DT Article DE code verification; error elimination; debugging; finite element method; boundary conditions ID ESTIMATOR AB The general procedure developed by Shih for eliminating computer coding errors has been both simplified for finite element applications and extended for use in the verification of the coding of forced and natural boundary conditions. To accomplish these two objectives simultaneously, use is made of volume weighted residuals for all elements within the solution regime and of area weighted boundary residuals for all elements having natural boundary conditions on one or more of their borders. This procedure can thus be used to verify finite element codes with a combination of both forced (Dirichlet) and natural (Neumann and Robbins) boundary conditions. Depending on the equations being solved and the boundary conditions they are being subjected to, this modification can make possible the implementation of Shih's general procedure into existing finite element codes without having to carry out any additional discretization steps. The employment of this modified procedure is illustrated using two-dimensional (2-D) stress analysis and transient heat conduction problems. Copyright (C) 1999 John Wiley & Sons, Ltd. C1 Indian Inst Technol, Dept Mech Engn, Kharagpur 721302, W Bengal, India. Indian Inst Technol, Dept Min Engn, Kharagpur 721302, W Bengal, India. USN Acad, Annapolis, MD 21402 USA. RP Loui, J (reprint author), Cent Min Res Inst, Barwa Rd, Dhanbad 826001, Bihar, India. NR 13 TC 1 Z9 1 U1 1 U2 1 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0029-5981 J9 INT J NUMER METH ENG JI Int. J. Numer. Methods Eng. PD MAR 30 PY 1999 VL 44 IS 9 BP 1187 EP 1204 PG 18 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA 174WZ UT WOS:000079060600001 ER PT J AU Shostko, AA Lohner, R Sandberg, WC AF Shostko, AA Lohner, R Sandberg, WC TI Surface triangulation over intersecting geometries SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING LA English DT Article DE unstructured grids; intersecting surfaces; mesh generation; advancing front ID MESH GENERATION AB A method for the rapid construction of meshes over intersecting triangulated shapes is described. The method is based on an algorithm that automatically generates a surface mesh from intersecting triangulated surfaces by means of Boolean intersection/union operations. After the intersection of individual components is obtained, the exposed surface parts are extracted. The algorithm is intended for rapid interactive construction of non-trivial surfaces in engineering design, manufacturing, visualization and molecular modelling applications. Techniques to make the method fast and general are described. The proposed algorithm is demonstrated on a number of examples, including intersections of multiple spheres, planes and general engineering shapes, as well as generation of surface and volume meshes around clusters of intersecting components followed by the computation of flow field parameters. Copyright (C) 1999 John Wiley & Sons, Ltd. C1 George Mason Univ, Dept Civil Engn, CSI, Fairfax, VA 22030 USA. Berkeley Res Associates Inc, Springfield, VA USA. USN, Res Lab, Washington, DC 20375 USA. RP Lohner, R (reprint author), George Mason Univ, Dept Civil Engn, CSI, MS 53C, Fairfax, VA 22030 USA. EM rlohner@science.gmu.edu NR 30 TC 24 Z9 30 U1 0 U2 6 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0029-5981 J9 INT J NUMER METH ENG JI Int. J. Numer. Methods Eng. PD MAR 30 PY 1999 VL 44 IS 9 BP 1359 EP 1376 DI 10.1002/(SICI)1097-0207(19990330)44:9<1359::AID-NME552>3.3.CO;2-2 PG 18 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA 174WZ UT WOS:000079060600009 ER PT J AU Ren, F Antonell, MJ Abernathy, CR Pearton, SJ LaRoche, JR Cole, MW Lothian, JR Gedridge, RW AF Ren, F Antonell, MJ Abernathy, CR Pearton, SJ LaRoche, JR Cole, MW Lothian, JR Gedridge, RW TI Nonalloyed high temperature ohmic contacts on Te-doped InP SO APPLIED PHYSICS LETTERS LA English DT Article ID EPITAXY AB We report on a thermal stability study of WSi0.79 contacts on Te-doped InP. The epitaxial InP layers were grown on Fe-doped semi-insulating InP substrates by metalorganic molecular beam epitaxy. Tri-isopropylindium-di-isopropyltellurium was used as the Te precursor and the doping level was 1.4 x 10(20) cm(-3). Contact metal, amorphous WSi0.79, was sputtered from a composite and an excellent specific contact resistance of 1 x 10(-6) Omega cm(2) was achieved. The specific contact resistivity was also measured at different temperature (25-200 degrees C) and it stayed fair contact. This is clear indication that the current transport through the contact dominates by tunneling. After alloying at temperatures up to 600 degrees C, there is no obvious change of specific contact resistance or sheet resistance. After 700 degrees C annealing, there was significant P out-diffusion detected and the specific contact resistance began to degrade. However, the contact metal morphology and edge definition were unaffected. After 800 degrees C annealing, there was evidence of In out-diffusion after and the surface morphology became rough. (C) 1999 American Institute of Physics. [S0003-6951(99)00913-4]. C1 Univ Florida, Gainesville, FL 32611 USA. Lucent Technol, Orlando, FL 32819 USA. USA, Res Lab, Aberdeen Proving Ground, MD 21005 USA. Multiplex Inc, S Plainfield, NJ 07080 USA. USN, Air Warfare Ctr, China Lake, CA 93555 USA. RP Ren, F (reprint author), Univ Florida, Gainesville, FL 32611 USA. NR 10 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 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAR 29 PY 1999 VL 74 IS 13 BP 1845 EP 1847 DI 10.1063/1.123688 PG 3 WC Physics, Applied SC Physics GA 180WM UT WOS:000079408500021 ER PT J AU Chow, GM Ding, J Zhang, J Lee, KY Surani, D Lawrence, SH AF Chow, GM Ding, J Zhang, J Lee, KY Surani, D Lawrence, SH TI Magnetic and hardness properties of nanostructured Ni-Co films deposited by a nonaqueous electroless method SO APPLIED PHYSICS LETTERS LA English DT Article ID THIN-FILMS; POLYOL PROCESS AB Nanostructured NixCo100-x films were deposited on Cu substrates by reducing the constituent metal salts in refluxing ethylene glycol at 194 degrees C. The average crystallite size increased with x, and reached a maximum of 64 nm when x = 100. The coercivity H (c) of the films measured in the direction perpendicular (perpendicular to) to the plane of the film was higher than that in the parallel (parallel to) direction. For the sample of x = 50, H (c perpendicular to) was 379 Oe, which was six times that of H (c parallel to.) Saturation magnetization M (s) in the film plane was 1016 emu/cm(3), and the remanent magnetization M (r) 636 emu/cm(3), giving a squareness ratio of 0.63. This film also had a Vickers hardness of 193. (C) 1999 American Institute of Physics. C1 Natl Univ Singapore, Dept Mat Sci, Singapore 117600, Singapore. USN, Res Lab, Washington, DC 20375 USA. RP Chow, GM (reprint author), Natl Univ Singapore, Dept Mat Sci, Kent Ridge, Singapore 117600, Singapore. RI Ding, Jun/C-5172-2011 NR 14 TC 36 Z9 36 U1 1 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAR 29 PY 1999 VL 74 IS 13 BP 1889 EP 1891 DI 10.1063/1.123703 PG 3 WC Physics, Applied SC Physics GA 180WM UT WOS:000079408500036 ER PT J AU Halstead, SB AF Halstead, SB TI Is there an inapparent dengue explosion? SO LANCET LA English DT Letter ID HEMORRHAGIC-FEVER C1 Off Naval Res, Arlington, VA 22217 USA. RP Halstead, SB (reprint author), Off Naval Res, Arlington, VA 22217 USA. NR 5 TC 32 Z9 34 U1 0 U2 2 PU LANCET LTD PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 0140-6736 J9 LANCET JI Lancet PD MAR 27 PY 1999 VL 353 IS 9158 BP 1100 EP 1101 DI 10.1016/S0140-6736(05)76460-6 PG 2 WC Medicine, General & Internal SC General & Internal Medicine GA 184LQ UT WOS:000079614000057 PM 10199378 ER PT J AU Santangelo, PG Roland, CM Puskas, JE AF Santangelo, PG Roland, CM Puskas, JE TI Rheology of star-branched polyisobutylene SO MACROMOLECULES LA English DT Article ID ENTANGLED POLYMER MELTS; VISCOELASTIC PROPERTIES; THERMORHEOLOGICAL COMPLEXITY; SHAPED POLYMERS; DILUTE-SOLUTION; LONG BRANCHES; TEMPERATURE; RELAXATION; DEPENDENCE; DISPERSION AB The rheology of high molecular weight, six-arm-star polyisobutylenes (PIB) was measured and compared to the behavior of linear PIB. The polymers had equivalent plateau moduli and conformed well in the terminal zone to the time-temperature superposition principle. Moreover, the temperature coefficients of the terminal relaxation times were identical for the star and linear polymers. Since the trans and gauche conformations in PIB have virtually the same energy, this absence of enhanced temperature sensitivity in star PIB, as well at the thermorheological simplicity, is consistent with an interpretation of the rheology of branched polymers based on an arm retraction mechanism. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. Univ Western Ontario, Dept Chem & Biochem Engn, London, ON N6A 5B9, Canada. RP USN, Res Lab, Div Chem, Code 6120, Washington, DC 20375 USA. NR 52 TC 34 Z9 34 U1 3 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 EI 1520-5835 J9 MACROMOLECULES JI Macromolecules PD MAR 23 PY 1999 VL 32 IS 6 BP 1972 EP 1977 DI 10.1021/ma9815556 PG 6 WC Polymer Science SC Polymer Science GA 180MH UT WOS:000079389400037 ER PT J AU Schroeder, MJ Roland, CM AF Schroeder, MJ Roland, CM TI Normal mode relaxation of polyisoprene in blends with vinyl polybutadienes SO MACROMOLECULES LA English DT Article ID SLOW DIELECTRIC-RELAXATION; DEUTERIUM MAGNETIC-RESONANCE; CIS-POLYISOPRENE; COMPONENT DYNAMICS; MOLECULAR-WEIGHT; NEMATIC INTERACTION; PROBE POLYISOPRENE; CONSTRAINT RELEASE; MISCIBLE BLENDS; DILUTE BLENDS AB When probe chains are dispersed in a network or higher molecular weight matrix,the expectation from the reptation model is that the terminal relaxation function will narrow, due to suppression of constraint release. Previous experiments found no support for this prediction, although they relied on time-temperature superpositioning to obtain spectra. These studies also made use of polyisoprene (PI)/1,4-polybutadiene blends, whose thermodynamic miscibility is problematic We report herein measurements acquired with a broad-band dielectric spectrometer of the terminal relaxation of PI in blends with polybutadiene having substantial 1,2-content. This mixture is thermodynamically miscible, thus excluding the possibility of phase separation. Corroborating earlier work, we find that the experimental behavior is qualitatively opposite to the prediction. Suppression of constraint release broadens the terminal dispersion, increasing the deviation from the theoretical relaxation function. This suggests that the common assumption that reptation and constraint release are independent processes is incorrect. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. USN Acad, Dept Chem, Annapolis, MD 21402 USA. RP USN, Res Lab, Div Chem, Code 6120, Washington, DC 20375 USA. NR 58 TC 13 Z9 13 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 EI 1520-5835 J9 MACROMOLECULES JI Macromolecules PD MAR 23 PY 1999 VL 32 IS 6 BP 2000 EP 2003 DI 10.1021/ma981271l PG 4 WC Polymer Science SC Polymer Science GA 180MH UT WOS:000079389400040 ER PT J AU Nosho, BZ Weinberg, WH Barvosa-Carter, W Bennett, BR Shanabrook, BV Whitman, LJ AF Nosho, BZ Weinberg, WH Barvosa-Carter, W Bennett, BR Shanabrook, BV Whitman, LJ TI Effects of surface reconstruction on III-V semiconductor interface formation: The role of III/V composition SO APPLIED PHYSICS LETTERS LA English DT Article ID SCANNING-TUNNELING-MICROSCOPY; PHOTOELECTRON-SPECTROSCOPY; ALSB; GASB(001); DIODES AB Using molecular-beam epitaxy and in situ scanning tunneling microscopy, we demonstrate how different reconstructions associated with different III-V growth surfaces can create interfacial roughness, and that an understanding of this phenomenon can be used to control the roughness on the atomic scale. Specifically, the different compositions of a clean InAs(001)-(2 X 4) surface (V/III=0.5 ML/0.75 ML) and an Sb-terminated one (similar to 1.7 ML/1 ML) cause the InSb-like interfacial surface to have a bilevel morphology. This surface roughness can be eliminated by depositing additional In to exactly compensate for the difference. It is likely that similar types of roughness occur in all heterostructures where the growth surface reconstruction changes at the interfaces, and that a similar procedure will be equally effective at reducing that roughness. (C) 1999 American Institute of Physics. [S0003-6951(99)01112-2]. C1 Univ Calif Santa Barbara, Ctr Quantized Elect Struct, Santa Barbara, CA 93106 USA. Univ Calif Santa Barbara, Dept Chem Engn, Santa Barbara, CA 93106 USA. USN, Res Lab, Washington, DC 20375 USA. RP Nosho, BZ (reprint author), Univ Calif Santa Barbara, Ctr Quantized Elect Struct, Santa Barbara, CA 93106 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 23 TC 35 Z9 36 U1 1 U2 12 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAR 22 PY 1999 VL 74 IS 12 BP 1704 EP 1706 DI 10.1063/1.123661 PG 3 WC Physics, Applied SC Physics GA 180VL UT WOS:000079405800021 ER PT J AU Asif, SA Wahl, KJ Colton, RJ AF Asif, SA Wahl, KJ Colton, RJ TI Nanoscale surface mechanical property measurements using force modulation technique. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Washington, DC 20375 USA. Univ Florida, Gainesville, FL 32611 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 21 PY 1999 VL 217 MA 150-COLL BP U626 EP U626 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 176JN UT WOS:000079148101937 ER PT J AU Baronavski, AP Owrutsky, JC AF Baronavski, AP Owrutsky, JC TI Femtosecond photoionization studies of acetyl unimolecular decomposition. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. RI Owrutsky, Jeffrey/K-7649-2012 NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 21 PY 1999 VL 217 MA 172-PHYS BP U327 EP U327 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 176JP UT WOS:000079148200975 ER EF