FN Thomson Reuters Web of Science™ VR 1.0 PT S AU Von Sternberg, R AF Von Sternberg, R BE Chandler, JLR VandeVijver, G TI Genomes and form - The case for teleomorphic recursivity SO CLOSURE: EMERGENT ORGANIZATIONS AND THEIR DYNAMICS SE ANNALS OF THE NEW YORK ACADEMY OF SCIENCES LA English DT Article; Proceedings Paper CT International Workshop on Closure - Emergent Organizations and Their Dynamics CY MAY 03-05, 1999 CL GHENT, BELGIUM SP Fund Sci Res, Res Community Evolut & Complex, Washington Evolutionary Syst Soc ID SELF-ORGANIZATION; CHROMOSOME BANDS; GENE-EXPRESSION; EVOLUTION; DNA; ELEMENTS; DROSOPHILA; PLANTS; HETEROCHROMATIN; MECHANISMS AB The genotype-phenotype (genome-form) distinction is considered by many to be fundamental to modern evolutionary thinking. Indeed, the premises that: DNA solely constitutes the genotype; that the phenotype is a transient product of the genotype, with the latter not only describing, but also implementing the construction of the former; and that the constructed materials and systems of the cell have no impact on the genotype, have become dogmas. Yet a vast body of data from molecular genetics reveals that cellular systems, directly and indirectly, alter the genome. Some of these data are reviewed. Proteins can influence mutations along the chromosomes, heritably modify the information content of DNA sequences, and, in some instances, reorganize the germline or somatic genome via DNA engineering pathways. These data suggest that the constructed (proteins, chromatin arrays, and metabolic pathways) has an important role in shaping the descriptor. Insofar as it is biochemically possible for states adopted by cellular structures to be stabilized and eventually memorized by engineering chromosomes, semantic closure can be transcended-meaning can be transferred from the domain of form to the genome, and this presumably ongoing process is termed teleomorphic recursivity. Throughout the paper, I implicitly argue that the genome-form partition is strictly a formal one, with no deeply material basis. C1 Smithsonian Inst, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Von Sternberg, R (reprint author), Smithsonian Inst, Dept Invertebrate Zool, NHB-163, Washington, DC 20560 USA. NR 48 TC 4 Z9 4 U1 0 U2 1 PU NEW YORK ACAD SCIENCES PI NEW YORK PA 2 EAST 63RD ST, NEW YORK, NY 10021 USA SN 0077-8923 BN 1-57331-248-7 J9 ANN NY ACAD SCI JI Ann.NY Acad.Sci. PY 2000 VL 901 BP 224 EP 236 PG 13 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA BQ61S UT WOS:000088969000022 PM 10818573 ER PT J AU Sadeghpour, HR Simbotin, I AF Sadeghpour, HR Simbotin, I TI Elastic and inelastic scattering of light SO COMMENTS ON MODERN PHYSICS LA English DT Article DE Raman and Rayleigh scattering; diagnostic probe; elastic and inelastic photon scattering ID ALKALI-METAL ATOMS; RAMAN-SCATTERING; SYMBIOTIC STARS; EMISSION-LINES; MULTIPHOTON ABSORPTION; IONIZATION THRESHOLD; O-2; RAYLEIGH; SPECTRUM; IDENTIFICATION AB Elastic (Rayleigh) and inelastic (Raman) scattering of light by atoms and molecules is described. Emphasis is on light scattering for probe of atomic and molecular reactions. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Sadeghpour, HR (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 50 TC 0 Z9 0 U1 2 U2 4 PU GORDON BREACH PUBLISHING, TAYLOR & FRANCIS GROUP PI PHILADELPHIA PA 325 CHESTNUT ST, 8TH FL, PHILADELPHIA, PA 19106 USA SN 1560-5892 J9 COMMENT MOD PHYS JI Comment Mod. Phys. PY 2000 VL 2 IS 4 BP D145 EP D156 PG 12 WC Physics, Multidisciplinary SC Physics GA 423NE UT WOS:000168181700004 ER PT S AU Cook, JW Socker, DG Korendyke, CM Howard, RA Brueckner, GE Karovska, M Wood, BE AF Cook, JW Socker, DG Korendyke, CM Howard, RA Brueckner, GE Karovska, M Wood, BE BE Watanabe, T Schwenn, R TI Search for velocity variations in Fe XIV 5304 angstrom coronagraph observations near activity minimum SO CORONAL STRUCTURE AND DYNAMICS NEAR SOLAR ACTIVITY MINIMUM SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E2 2 Symposium of COSPAR Scientific Commission E Held during the 32nd COSPAR Scientific Assembly CY JUL 12-19, 1998 CL NAGOYA, JAPAN SP Inst Space & Astronaut Sci, European Space Agcy, NASA, Russian Space Agcy, Comm Space Res AB The LASCO C1 coronagraph on the SOHO satellite observes the solar corona from 1.1 to 3.0 R-., and contains a Fabry-Perot interferometer which can image the corona in the 1.8 million K Fe XIV green line. We designed an observing program with reduced spatial coverage and reduced profile coverage at only three wavelengths to study coronal heating in off-limb structures at high temporal resolution. We illustrate the observations from 31 March 1997 of a bright loop system above an active region off the northeast limb. (C) 2000 COSPAR. Published by Elsevier Science Ltd. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Cook, JW (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. NR 1 TC 3 Z9 3 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0273-1177 J9 ADV SPACE RES PY 2000 VL 25 IS 9 BP 1883 EP 1886 DI 10.1016/S0273-1177(99)00601-8 PG 4 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BP67C UT WOS:000085822100036 ER PT S AU Mobius, E Gloeckler, G Goldstein, B Habbal, S McNutt, R Randolph, J Title, A Tsurutani, B AF Mobius, E Gloeckler, G Goldstein, B Habbal, S McNutt, R Randolph, J Title, A Tsurutani, B BE Watanabe, T Schwenn, R TI Here comes solar probe! SO CORONAL STRUCTURE AND DYNAMICS NEAR SOLAR ACTIVITY MINIMUM SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT E2 2 Symposium of COSPAR Scientific Commission E Held during the 32nd COSPAR Scientific Assembly CY JUL 12-19, 1998 CL NAGOYA, JAPAN SP Inst Space & Astronaut Sci, European Space Agcy, NASA, Russian Space Agcy, Comm Space Res AB Despite recent advances, fundamental questions remain about the nature of the solar corona and the solar wind: 1) What heats the corona and accelerates the solar wind? 2) Where do the different types of solar wind originate? 3) Where and how are energetic particles produced and transported near the Sun? 4) What role do plasma turbulence and waves play in the corona and solar wind production? 5) What is the nature of the magnetic field and photospheric structures near the solar poles? Flying a trajectory perpendicular to the Earth-Sun line during its perihelion passage, Solar Probe will use in-situ and imaging instruments to provide the first three dimensional viewing of the corona, direct observations of solar polar regions, and local sampling of the solar environment. These primary observations are complemented by context-setting measurements and Earth-based observations. Solar Probe is currently scheduled for launch in February 2007 as the third in the new Outer Planets/Solar Probe mission line of NASA and will arrive at the Sun in 2010 under solar maximum conditions with a second closest approach near solar minimum in 2015. (C) 2000 COSPAR. Published by Elsevier Science Ltd. C1 Univ New Hampshire, Ctr Space Sci, Durham, NH USA. Univ Maryland, College Pk, MD 20742 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. Lockheed Martin Adv Technol Lab, Palo Alto, CA 94304 USA. RP Mobius, E (reprint author), Univ New Hampshire, Ctr Space Sci, Durham, NH USA. RI McNutt, Ralph/E-8006-2010; OI McNutt, Ralph/0000-0002-4722-9166; Moebius, Eberhard/0000-0002-2745-6978 NR 11 TC 4 Z9 4 U1 0 U2 1 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0273-1177 J9 ADV SPACE RES PY 2000 VL 25 IS 9 BP 1961 EP 1964 DI 10.1016/S0273-1177(99)00610-9 PG 4 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BP67C UT WOS:000085822100053 ER PT S AU Schlegel, EM Ryder, S Staveley-Smith, L Colbert, E Petre, R Dopita, M Campbell-Wilson, D AF Schlegel, EM Ryder, S Staveley-Smith, L Colbert, E Petre, R Dopita, M Campbell-Wilson, D BE Holt, SS Zhang, WW TI Properties of SN1978K from multi-wavelength observations SO COSMIC EXPLOSIONS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Annual Astrophysics Conference on Cosmic Explosions CY OCT 11-13, 1999 CL COLLEGE PK, MD SP Univ Maryland ID X-RAY-EMISSION; H-II REGION; CIRCUMSTELLAR INTERACTION; SUPERNOVA-REMNANTS; SN 1978K; SN-1987A; SN-1978K; NGC-1313; SPECTRA; CLOUDS AB We update the light curves from the X-ray, optical, and radio bandpasses which we have assembled over the past decade, and present two observations in the ultraviolet using the Hubble Space Telescope Faint Object Spectrograph. The HRI X-ray light curve is constant within the errors over the entire observation period which is confirmed by ASCA GIS data obtained in 1993 and 1995. In the UV, we detected the Mg II doublet at 2800 Angstrom and a line at similar to 3190 Angstrom attributed to He I 3187 at SN1978K's position. The optical light curve is formally constant within the errors, although a slight upward trend may be present. The radio light curve continues its steep decline. The longer time span of our radio observations compared to previous studies shows that SN1978K belongs in the class of highly X-ray and radio-luminous supernovae. The Mg II doublet flux ratio implies the quantity of line optical depth times density is similar to 10(14) cm(-3). The emission site must lie in the shocked gas. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Schlegel, EM (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Staveley-Smith, Lister/A-1683-2011; Dopita, Michael/P-5413-2014 OI Staveley-Smith, Lister/0000-0002-8057-0294; Dopita, Michael/0000-0003-0922-4986 NR 25 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-943-2 J9 AIP CONF PROC PY 2000 VL 522 BP 155 EP 159 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ55Z UT WOS:000088762100018 ER PT S AU Kenyon, SJ AF Kenyon, SJ BE Holt, SS Zhang, WW TI Accretion disk eruptions in the FU Orionis variable stars SO COSMIC EXPLOSIONS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Annual Astrophysics Conference on Cosmic Explosions CY OCT 11-13, 1999 CL COLLEGE PK, MD SP Univ Maryland ID Z-CANIS-MAJORIS; T-TAURI STARS; YOUNG STELLAR OBJECTS; HERBIG-HARO OBJECTS; L1551 IRS-5; OBSERVATIONAL CONSTRAINTS; INFRARED-SPECTROSCOPY; MOLECULAR OUTFLOWS; BINARY-SYSTEM; RNO 1B/1C AB The pre-main sequence FU Orionis variables undergo 3-6 mag outbursts lasting from decades to centuries. The outbursts occur in a large, self-luminous accretion disk surrounding a young star with an age of 1-10 x 10(5) yr. Models of thermally unstable disks generally account for the scale and duration of the outburst. The accretion rate through the disk is large enough to add similar to 1% of a solar mass to the central star in each outburst. Repetitive eruptions could add greater than or similar to 20% of a solar mass to each pre-main sequence star in the solar neighborhood. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Kenyon, SJ (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 87 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-943-2 J9 AIP CONF PROC PY 2000 VL 522 BP 411 EP 420 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ55Z UT WOS:000088762100052 ER PT B AU Huchra, JP AF Huchra, JP BE Courteau, S Strauss, MA Willick, JA TI The 2MASS redshift survey SO COSMIC FLOWS 1999: TOWARDS AN UNDERSTANDING OF LARGE-SCALE STRUCTURE SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT International Workshop on Cosmic Flows: Towards an Understanding of Large-Scale Structure CY JUL 13-17, 1999 CL UNIV VICTORIA, VICTORIA, CANADA SP Herzberg Inst Astrophys, Canadian Inst Theoret Astrophys HO UNIV VICTORIA ID STATE; OMEGA AB The determination of Omega(M) and galaxy biasing by matching the local Cosmic velocity field with the local galaxy density field is a. key problem in cosmology Previous attempts, using either optically or 60 micron selected galaxies, have given somewhat ambiguous answers due to problems with parent samples - non-uniformities due to extinction and other problems, sparse sampling, sampling biased towards recent star formation rather than mass. We have begun an ambitious new redshift and distance survey based on a 2 micron selected sample of galaxies from the 2MASS survey. This will be a dense, uniform survey that better traces galaxy mass. The 2MRS should provide the best view of the whole sky local density field to z similar to 0.1, and the densest sampling local velocity field to z similar to 0.05. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Huchra, JP (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 9 TC 7 Z9 7 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-028-5 J9 ASTR SOC P PY 2000 VL 201 BP 96 EP 102 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ38S UT WOS:000088225500013 ER PT J AU Balch, WM Drapeau, DT Fritz, JJ AF Balch, WM Drapeau, DT Fritz, JJ TI Monsoonal forcing of calcification in the Arabian Sea SO DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY LA English DT Article ID EMILIANIA-HUXLEYI; COCCOLITHOPHORE BLOOM; OPTICAL-PROPERTIES; CALCIUM-CARBONATE; INORGANIC CARBON; NORTH-ATLANTIC; DEEP OCEAN; PHYTOPLANKTON; SEDIMENTATION; TEMPERATURE AB This paper summarizes our results on the changes in pelagic calcification and the standing stock of calcium carbonate associated with the SW Monsoon and NE Monsoon (cruises TN049 and TN053 of the U.S. JGOFS study, respectively) in the northern portion of the Arabian Sea. Mean calcification was similar to 3X greater during the SW Monsoon than during the NE Monsoon. Calcification per coccolithophore was 7-10X higher, and the ratio of calcification to photosynthesis (C/P) was 40-45% higher during the SW Monsoon. The turnover time of PIC was not statistically different between the two cruises (similar to 4.5 d averaged over the euphotic zone). Turnover time of POC increased significantly between TN049 and TN053 (from similar to 3 to 6 d over the euphotic zone). We discuss vertical sections of coccolithophore: abundance, carbon standing stocks and carbon fixation. Coccolithophore calcification was usually about 1-5% of community photosynthesis. The ratio of calcification to photosynthesis spanned almost 2 orders of magnitude, and was not significantly different from the ratio of the PIC and POC standing stocks. We compare surface PIC and POC production rates to sediment trap fluxes from the same region. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Bigelow Lab Ocean Sci, W Boothbay Harbor, ME 04575 USA. Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. RP Balch, WM (reprint author), Bigelow Lab Ocean Sci, POB 475, W Boothbay Harbor, ME 04575 USA. NR 67 TC 39 Z9 40 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0967-0645 J9 DEEP-SEA RES PT II JI Deep-Sea Res. Part II-Top. Stud. Oceanogr. PY 2000 VL 47 IS 7-8 BP 1301 EP 1337 DI 10.1016/S0967-0645(99)00145-9 PG 37 WC Oceanography SC Oceanography GA 297LU UT WOS:000086085000005 ER PT B AU Ho, PTP AF Ho, PTP BE Garzon, F Eiroa, C DeWinter, D Mahoney, TJ TI Observational aspects of protostellar disks SO DISKS, PLANETESIMALS, AND PLANETS, PROCEEDINGS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Euroconference on Disks, Planetesimals, and Planets CY JAN 24-28, 2000 CL PUERTO LA CRUZ, SPAIN SP European Community, Spain Minist Sci & Educ, Autonomous Univ Madrid, Spanish Natl Res Council, Spanish Astron Soc, Banco Bilbao Vizcaya, Inst Astrofis Canarias, DISA ID HL TAURI; ROTATION; SCALE; ENVELOPE; MOTIONS; SYSTEM; AU AB Protostellar disks span the size scale from about 100 AU to maybe 10 000 AU. On the large scale, millimeter-wavelength interferometers have been successful in resolving the structures and the kinematics of the circumstellar cloud cores and disks. In particular, spectroscopy has revealed evidence for infall, outflow, and rotation. On the smaller scales, imaging becomes more difficult, although both HST and centimeter-wavelength interferometry have been able to see the inner dusty circumstellar disks. However, because of the low luminosity of such inner disks, kinematics and mass determinations remain very difficult. Recently, a new way to study these inner disks has become possible through proper-motion studies of water masers associated with the disks. In this paper, we will review the observational status of these various studies. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Ho, PTP (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 17 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-051-X J9 ASTR SOC P PY 2000 VL 219 BP 83 EP 94 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BR94A UT WOS:000168122500012 ER PT B AU Hartmann, L AF Hartmann, L BE Garzon, F Eiroa, C DeWinter, D Mahoney, TJ TI Accretion disks SO DISKS, PLANETESIMALS, AND PLANETS, PROCEEDINGS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Euroconference on Disks, Planetesimals, and Planets CY JAN 24-28, 2000 CL PUERTO LA CRUZ, SPAIN SP European Community, Spain Minist Sci & Educ, Autonomous Univ Madrid, Spanish Natl Res Council, Spanish Astron Soc, Banco Bilbao Vizcaya, Inst Astrofis Canarias, DISA ID T-TAURI-STARS; YOUNG STELLAR OBJECTS; GIANT PLANETS; MAGNETOSPHERIC ACCRETION; CIRCUMSTELLAR DISKS; ORBITAL MIGRATION; MILLIMETER-WAVE; GAP FORMATION; EMISSION; CONTINUUM AB I review the observational constraints on disk accretion in low-mass, pre-main-sequence stars, and consider their implications for theories of planet formation. T Tauri stars accrete roughly 0.01M(circle dot) over their lifetimes of a few Myr, in approximate agreement with estimates from mm-wave dust emission. However, the best simple models which reconcile observed disk masses, accretion rates, and sizes suggest relatively fast viscous evolution, which could pose problems for planet formation. These difficulties could be eased if observations of dust emission substantially underestimate the amount of mass present in disks, especially at small radii, which might occur if we have underestimated the amount of grain growth that has occurred in these disks. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Hartmann, L (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 36 TC 1 Z9 1 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-051-X J9 ASTR SOC P PY 2000 VL 219 BP 95 EP 107 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BR94A UT WOS:000168122500013 ER PT B AU van den Ancker, ME AF van den Ancker, ME BE Garzon, F Eiroa, C DeWinter, D Mahoney, TJ TI ISO observations of pre-main-sequence and vega-type stars SO DISKS, PLANETESIMALS, AND PLANETS, PROCEEDINGS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Euroconference on Disks, Planetesimals, and Planets CY JAN 24-28, 2000 CL PUERTO LA CRUZ, SPAIN SP European Community, Spain Minist Sci & Educ, Autonomous Univ Madrid, Spanish Natl Res Council, Spanish Astron Soc, Banco Bilbao Vizcaya, Inst Astrofis Canarias, DISA ID YOUNG-STELLAR-OBJECTS; CIRCUMSTELLAR DISKS; BETA-PICTORIS; WAVELENGTH SPECTROMETER; SWS OBSERVATIONS; SPECTRUM; EMISSION; SPECTROSCOPY; TEMPERATURE; REGIONS AB I present an overview of the results obtained by the Infrared Space Observatory (ISO) on circumstellar material in pre-main-sequence (PMS) stars. Results obtained for embedded YSOs, Herbig Ae/Be systems and T Tauri stars are reviewed and their connection to the disks around Vega-type systems is discussed. Although the gas contents of the PMS environment will also be discussed briefly, this review will mainly focus on the composition, mineralogy and evolution of dust in these systems, and the results will be compared to those found in other classes of objects, including Solar System comets. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP van den Ancker, ME (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS 42, Cambridge, MA 02138 USA. NR 40 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-051-X J9 ASTR SOC P PY 2000 VL 219 BP 242 EP 254 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BR94A UT WOS:000168122500030 ER PT B AU Charbonneau, D Noyes, RW AF Charbonneau, D Noyes, RW BE Garzon, F Eiroa, C DeWinter, D Mahoney, TJ TI Present and near-future reflected-light searches for close-in planets SO DISKS, PLANETESIMALS, AND PLANETS, PROCEEDINGS SE Astronomical Society of the Pacific Conference Series LA English DT Proceedings Paper CT Euroconference on Disks, Planetesimals, and Planets CY JAN 24-28, 2000 CL PUERTO LA CRUZ, SPAIN SP European Community, Spain Minist Sci & Educ, Autonomous Univ Madrid, Spanish Natl Res Council, Spanish Astron Soc, Banco Bilbao Vizcaya, Inst Astrofis Canarias, DISA ID UPSILON-ANDROMEDAE; TAU-BOOTIS; GIANT PLANETS; COMPANIONS; STARS AB Close-in extrasolar giant planets may be directly detectable by their reflected light due to the proximity of the planet to the illuminating star. The spectrum of the system will contain a reflected-light component that varies in amplitude and Doppler shift as the planet orbits the star. Intensive searches for this effect have been carried out for only one extrasolar planet system, tau Boo. There exist several other attractive targets, including the transiting planetary system RD 209458. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM dcharbonneau@cfa.harvard.edu; rnoyes@cfa.harvard.edu NR 17 TC 3 Z9 3 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-051-X J9 ASTR SOC P PY 2000 VL 219 BP 461 EP 467 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BR94A UT WOS:000168122500059 ER PT B AU Latham, DW AF Latham, DW BE Garzon, F Eiroa, C DeWinter, D Mahoney, TJ TI G Dwarf Planet Search SO DISKS, PLANETESIMALS, AND PLANETS, PROCEEDINGS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Euroconference on Disks, Planetesimals, and Planets CY JAN 24-28, 2000 CL PUERTO LA CRUZ, SPAIN SP European Community, Spain Minist Sci & Educ, Autonomous Univ Madrid, Spanish Natl Res Council, Spanish Astron Soc, Banco Bilbao Vizcaya, Inst Astrofis Canarias, DISA ID SPECTROGRAPH AB In 1997 August we made the first observations for our G Dwarf Planet Search using the High Resolution Echelle Spectrograph (HIRES) with its iodine gas absorption cell on Keck 1 under NASA time. As of 2000 February we had been assigned 21 nights and had accumulated 4180 stellar spectra of more than 900 targets chosen from a sample of nearby dwarfs with spectral types between late F and early K. Our strategy is to carry out an initial reconnaissance of approximately 1000 stars to identify candidate systems for follow-up studies. An innovative approach to the analysis of the HIRES spectra by team members in Tel Aviv, led by T. Mazeh, has achieved a precision of about 10 m s(-1) per velocity observation as judged by the median rms for the stars with multiple observations. Follow-up observations of interesting candidates are under way. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Latham, DW (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 17 TC 5 Z9 5 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-051-X J9 ASTR SOC P PY 2000 VL 219 BP 596 EP 601 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BR94A UT WOS:000168122500077 ER PT J AU Flores, A Gradinarsky, LP Elosegui, P Elgered, G Davis, JL Rius, A AF Flores, A Gradinarsky, LP Elosegui, P Elgered, G Davis, JL Rius, A TI Sensing atmospheric structure: Tropospheric tomographic results of the small-scale GPS campaign at the Onsala Space Observatory SO EARTH PLANETS AND SPACE LA English DT Article ID RADIO INTERFEROMETRY; GRADIENTS; DELAY; GEODESY; AIR AB Tropospheric tomography using data from local networks of Global Positioning System (GPS) receivers is producing encouraging spatio-temporal representations of the wet refractivity field. In this work we present the results from a small-scale geodetic experiment that we carried out at the Onsala Space Observatory. Seven GPS receivers distributed within a radius of 3 km from the center, were deployed during 21 days in the summer 1998. The limited number of sites and their spatial configuration present a challenge for tropospheric tomography Using novel GPS techniques to determine the vertical structure of the atmosphere, we observed, for one session, a strong horizontal water-vapor gradient with a leading edge at higher altitude than the trailing edge, entering from the north. The vertical structure obtained independently using tomographic techniques matched such situation. These results suggest tomography is a promising technique for the determination of the spatio-temporal structure of the atmosphere. We will present preliminary results of the tropospheric tomography, using simulations and experimental data, together with some comparisons with radiosonde data. C1 Chalmers Univ Technol, Onsala Space Observ, Gothenburg, Sweden. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RI Davis, James/D-8766-2013; Antonio, Rius/A-4873-2012; Elgered, Gunnar/B-7052-2016 OI Davis, James/0000-0003-3057-477X; Antonio, Rius/0000-0002-5947-2649; Elgered, Gunnar/0000-0001-5711-0073 NR 15 TC 8 Z9 14 U1 0 U2 1 PU TERRA SCIENTIFIC PUBL CO PI TOKYO PA 2003 SANSEI JIYUGAOKA HAIMU, 5-27-19 OKUSAWA, SETAGAYA-KU, TOKYO, 158, JAPAN SN 1343-8832 J9 EARTH PLANETS SPACE JI Earth Planets Space PY 2000 VL 52 IS 11 BP 941 EP 945 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 385LB UT WOS:000166004800009 ER PT J AU Marvin, UB AF Marvin, UB TI Iron meteorites and controversies over the origin of erratic boulders SO ECLOGAE GEOLOGICAE HELVETIAE LA English DT Article; Proceedings Paper CT Meeting of the International-Commission-on-the-History-of-the-Geological-Sciences (INHIGEO) CY SEP 09-11, 1998 CL NEUCHATEL, SWITZERLAND SP Int Commiss Hist Geol Sci AB In the 1770s and 1780s reports circulated through Europe that two large masses of metallic iron had been discovered in remote regions on opposite sides of the Earth: one in Siberia, the other in the chacos of northern Argentina. Located far from any known volcanoes or sites of primitive smelting operations, the irons initially were classed with the huge erratic boulders of granite, basalt, and other common rocks that were scattered over much of Europe. Acrimonious debates arose over whether the exotic blocks had been dispersed early in the Earth's history by violent explosions ol by torrential waters. The first naturalist to envision a separate mode of origin for the irons was Ernst F. F. Chladni of Wittenberg, who proposed, in 1794. that masses of iron and stones fall to the Earth from space. At first, this "infamous" hypothesis was roundly criticized. but, within the next five years, four witnessed falls of stones occurred and were widely publicized. By 1802, chemical analyses had shown that, unlike granites and other common rocks, the erratic irons and metal grains found in the fallen stones all consisted of nickel-iron - a previously unknown alloy. These observations quickly led to the acceptance of meteorites as valid natural phenomena. Another four decades would pass before the concept of continental ice sheets would provide a satisfactory explanation of the distribution of large crustal erratics. In recent years we have learned that, under certain conditions, the Antarctic ice sheet concentrates frozen-in meteorites, of many different varieties and dates of fall, in virtual placer deposits on so-called stranding surfaces. This new linking of meteorites with ice sheets has provided the international research community with an abundance of valuable samples from other bodies in the solar system. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Marvin, UB (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 37 TC 1 Z9 1 U1 0 U2 0 PU BIRKHAUSER VERLAG AG PI BASEL PA VIADUKSTRASSE 40-44, PO BOX 133, CH-4010 BASEL, SWITZERLAND SN 0012-9402 J9 ECLOGAE GEOL HELV JI Eclogae Geol. Helv. PY 2000 VL 93 IS 1 BP 25 EP 31 PG 7 WC Geology SC Geology GA 350VW UT WOS:000089122700002 ER PT J AU McShea, WJ AF McShea, WJ TI The influence of acorn crops on annual variation in rodent and bird populations SO ECOLOGY LA English DT Article DE acorn production; avian nest predation; eastern deciduous forests; Odocoileus virginianus; Peromyscus; Quercus; Sciurus; Tamias; white-tailed deer ID WHITE-FOOTED MICE; LYME-DISEASE RISK; NEST PREDATION; FOREST FRAGMENTATION; COMMUNITY DYNAMICS; RED SQUIRRELS; TAILED DEER; FOOD; MAST; TRENDS AB I recorded mast production by oaks (Quercus sp.) at 12 forested sites in western Virginia for 6-12 yr and measured its impact on the abundance of small mammals, understory vegetation, and artificial-nest predation. White-tailed deer (Odocoileus virginianus) were excluded from half the 4-ha sites after at least one season of data collection. My hypothesis was that annual variation in acorn crops affected multiple species and that the strength of those interactions is mediated by white-tailed deer. The acorn crop was variable across sites and year, with some of the between-site variability explained by differences in elevation. All sites experienced at least one mast failure, and mast failure years were generally consistent across sites. White-footed mouse (Peromyscus leucopus), eastern chipmunk (Tamias striatus), and gray squirrel (Sciurus carolinensis) populations were significantly correlated with annual fluctuations in the acorn crop. The exclusion of deer had a significant impact on P. leucopus and T, striatus populations by increasing the number of animals captured following low acorn mast years. Annual fluctuations in the acorn crop, but not in rodent densities, were significantly correlated with the rates of predation on artificial nests the next summer. There was no significant interaction between predation rates and the exclusion of deer. An index from the Breeding Bird Survey (BBS) for Virginia was used to measure regional numbers for 11 common species captured at the sites. The index for two understory species was significantly negatively correlated with the mean acorn crop measured 2 yr previously. The effect of white-tailed deer on the forest community was not consistent across all conditions, as sites with large acorn crops were not strongly influenced by deer. These data are consistent with the hypothesis that mast crops from oaks serve as important determinants of community function within Appalachian forests. C1 Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA 22630 USA. RP McShea, WJ (reprint author), Natl Zool Pk, Conservat & Res Ctr, 1500 Remount Rd, Front Royal, VA 22630 USA. NR 63 TC 151 Z9 155 U1 7 U2 73 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 1707 H ST NW, STE 400, WASHINGTON, DC 20006-3915 USA SN 0012-9658 J9 ECOLOGY JI Ecology PD JAN PY 2000 VL 81 IS 1 BP 228 EP 238 DI 10.1890/0012-9658(2000)081[0228:TIOACO]2.0.CO;2 PG 11 WC Ecology SC Environmental Sciences & Ecology GA 277BT UT WOS:000084913400019 ER PT J AU Bilby, K AF Bilby, K TI Ethnicity identity and music: The musical construction of place SO ETHNIC AND RACIAL STUDIES LA English DT Book Review C1 Smithsonian Inst, Dept Anthropol, Washington, DC 20560 USA. RP Bilby, K (reprint author), Smithsonian Inst, Dept Anthropol, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 4 PU ROUTLEDGE PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0141-9870 J9 ETHNIC RACIAL STUD JI Ethn. Racial Stud. PD JAN PY 2000 VL 23 IS 1 BP 166 EP 168 PG 3 WC Ethnic Studies; Sociology SC Ethnic Studies; Sociology GA 274QA UT WOS:000084775500022 ER PT S AU Kaaret, P AF Kaaret, P BE McConnell, ML Ryan, JM TI Pulsar radiation, quantum gravity, and testing fundamental physics with astrophysics SO FIFTH COMPTON SYMPOSIUM SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 5th Compton Symposium CY SEP 15-17, 1999 CL UNIV NEW HAMPSHIRE, PORTSMOUTH, NH SP Univ New Hampshire, NASA, Goddard Space Flight Ctr, Compton Gamma-Ray Observ Sci Support Ctr HO UNIV NEW HAMPSHIRE ID LIMITS; SPEED; LIGHT AB I describe recent efforts towards using high-energy astrophysical observations to measure energy dependent variations in the speed of light predicted in some forms of quantum gravity. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Kaaret, P (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-932-7 J9 AIP CONF PROC PY 2000 VL 510 BP 277 EP 279 PG 3 WC Astronomy & Astrophysics; Instruments & Instrumentation SC Astronomy & Astrophysics; Instruments & Instrumentation GA BQ14E UT WOS:000087291800054 ER PT S AU Catanese, M AF Catanese, M BE McConnell, ML Ryan, JM TI Ground-based gamma-ray astronomy SO FIFTH COMPTON SYMPOSIUM SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 5th Compton Symposium CY SEP 15-17, 1999 CL UNIV NEW HAMPSHIRE, PORTSMOUTH, NH SP Univ New Hampshire, NASA, Goddard Space Flight Ctr, Compton Gamma-Ray Observ Sci Support Ctr HO UNIV NEW HAMPSHIRE ID MULTIWAVELENGTH OBSERVATIONS; SUPERNOVA-REMNANTS; MARKARIAN-421; VARIABILITY; ORIGIN; FLARE AB Ground-based gamma-ray astronomy has become an active astrophysical discipline with four confirmed sources of TeV gamma-rays, two plerionic supernova remnants (SNRs) and two BL Lac objects (BL Lacs). An additional nine objects tone plerion, three shell-type SNRs, one X-ray binary, and four (BL Lacs) have been detected but have not been confirmed by independent detections. None of the galactic sources require the presence of hadronic cosmic rays, so definitive evidence of their origin remains elusive. Mrk 421 and Mrk 501 are weak EGRET sources but they exhibit extremely variable TeV emission with spectra that extend beyond 10 TeV. They also exhibit correlations with lower energy photons during multi-wavelength campaigns, providing tests of emission models. Next generation telescopes like VERITAS hold the promise of moving this field dramatically forward. C1 Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. RP Catanese, M (reprint author), Whipple Observ, Harvard Smithsonian Ctr Astrophys, POB 97, Amado, AZ 85645 USA. NR 24 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-932-7 J9 AIP CONF PROC PY 2000 VL 510 BP 619 EP 626 PG 8 WC Astronomy & Astrophysics; Instruments & Instrumentation SC Astronomy & Astrophysics; Instruments & Instrumentation GA BQ14E UT WOS:000087291800116 ER PT B AU Williams, MR AF Williams, MR BE Rojas, R Hashagen, U TI A preview of things to come: Some remarks on the first generation of computers SO FIRST COMPUTERS-HISTORY AND ARCHITECTURES SE History of Computing LA English DT Proceedings Paper CT International Conference on the History of Computing CY AUG, 1998 CL HEINZ NIXDORF MUSEUMS FORUM, PADERBORN, GERMANY SP Deutsch Forsch GmbH, Freie Univ Berlin HO HEINZ NIXDORF MUSEUMS FORUM AB The editors of this volume have asked me to prepare this introduction in order to "set the scene" for the other papers. It is often difficult to know just how much knowledge people have about the early days of computing - however you define that term. If one reads a sophisticated description which details some small aspect of a topic, it is impossible to follow if your intention was simply to learn some basic information. On the other hand, if you are an historian that has spent your entire working life immersed in the details of a subject, it is rather a waste of time to carefully examine something which presents the well known facts to you, yet again. This means that, no matter what I include here, I will almost certainly discuss things of no interest to many of you! What I do intend to do is to review the basics of early computer architecture for the uninitiated, but to try and do it in a way that might shed some light on aspects that are often not fully appreciated this means that I run the risk of boring everyone. C1 Smithsonian Inst, Amer Museum Nat Hist, Washington, DC 20560 USA. NR 7 TC 3 Z9 3 U1 0 U2 0 PU MIT PRESS PI CAMBRIDGE PA FIVE CAMBRIDGE CENTER, CAMBRIDGE, MA 02142 USA BN 0-262-18197-5 J9 HIST COMPUT-MIT PRES PY 2000 BP 1 EP 13 PG 13 WC History & Philosophy Of Science SC History & Philosophy of Science GA BQ98U UT WOS:000165281300001 ER PT B AU Beckert, T AF Beckert, T BE Weiss, A Abel, TG Hill, V TI Temperature of the first HII regions SO FIRST STARS SE ESO ASTROPHYSICS SYMPOSIA LA English DT Proceedings Paper CT MPA/ESO Workshop on the First Stars CY AUG 04-06, 1999 CL GARCHING, GERMANY SP MPA, European So Observ AB The first stellar sources to reionize the interstellar and intergalactic medium during galaxy formation will ionize gas of primordial composition. Energy balance in these metal-free HII regions require gas temperatures between several times 10(4) K and a few times 10(5)K. We can exclude higher temperature solutions based on a separate electron energy balance and lower temperatures from energy constrains at the ionization front. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Beckert, T (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-67222-2 J9 ESO ASTROPHY SYMP PY 2000 BP 225 EP 226 DI 10.1007/10719504_43 PG 2 WC Astronomy & Astrophysics; Chemistry, Inorganic & Nuclear; Physics, Nuclear SC Astronomy & Astrophysics; Chemistry; Physics GA BQ54S UT WOS:000088721200043 ER PT J AU Steves, BP Cowen, RK Malchoff, MH AF Steves, BP Cowen, RK Malchoff, MH TI Settlement and nursery habitats for demersal fishes on the continental shelf of the New York Bight SO FISHERY BULLETIN LA English DT Article ID CANONICAL CORRESPONDENCE-ANALYSIS; MIDDLE ATLANTIC BIGHT; PLEURONECTES-PLATESSA L; EARLY LIFE STAGES; JUVENILE FLATFISH; INTERANNUAL VARIABILITY; YELLOWTAIL FLOUNDER; SPATIAL VARIATION; GRAND BANK; RECRUITMENT AB Although juvenile fish are studied extensively in estuarine and nearshore environments, surprisingly little is known about the basic habitat requirements of juveniles for offshore settlement and nursery areas. Between June 1996 and July 1997, settlement and nursery habitats of age-0 (early juvenile) demersal fish on the continental shelf of the New York Eight were investigated by using a two-meter beam trawl. Replicate tows at 21 stations along three cross-shelf transects (20-95 m depth), were sampled on a near monthly basis to determine general ecology (21,309 fish collected in 659 tows). Of the 47 species collected, 33 included age-0 juveniles, and 25 included near-settlement size individuals. The two dominant species, Pleuronectes ferrugineus and Merluccius bilinearis, constituted 88.9% of the total catch of age-0 fish. Of all age-0 fish, 94% were collected during summer and fall. Comparisons of weighted means and the use of canonical correspondence analysis determined that settlement and nursery habitats across the shelf are primarily delineated by depth, temperature, and time of year. Three zones across the shelf (inner, middle, and outer) each had distinct juvenile fish assemblages. Knowledge gained about the distribution and quality of juvenile habitat for commercially important offshore species should facilitate their improved management. C1 SUNY Stony Brook, Marine Sci Res Ctr, Stony Brook, NY 11794 USA. New York Sea Grant Program, Riverhead, NY 11901 USA. RP Steves, BP (reprint author), Smithsonian Environm Res Ctr, Marine Invas Lab, 648 Contees Wharf Rd, Edgewater, MD 21037 USA. NR 70 TC 8 Z9 9 U1 0 U2 2 PU NATL MARINE FISHERIES SERVICE SCIENTIFIC PUBL OFFICE PI SEATTLE PA 7600 SAND POINT WAY NE BIN C15700, SEATTLE, WA 98115 USA SN 0090-0656 J9 FISH B-NOAA JI Fish. Bull. PD JAN PY 2000 VL 98 IS 1 BP 167 EP 188 PG 22 WC Fisheries SC Fisheries GA 287NV UT WOS:000085512900013 ER PT B AU Norrbom, AL Condon, MA AF Norrbom, AL Condon, MA BE Aluja, M Norrbom, AL TI Phylogeny of the subfamily Blepharoneurinae SO FRUIT FLIES (TEPHRITIDAE): PHYLOGENY AND EVOLUTION OF BEHAVIOR LA English DT Proceedings Paper CT Symposium Fruit Flies (Tephritidae) - Phylogeny and Evolution of Behavior CY FEB 16-21, 1998 CL VERACRUZ, MEXICO SP Campana Nacl Moscas Fruta, USDA, FAS, ICD, Div Res & Sci Exchanges, Int Org Biol Control Noxious Anim & Plants, Inst Ecol AC, Consejo Nacl Ciencia & Tecnol, Acad Mexicana Ciencias, Fdn Mexico Estados Unidos Ciencia, Comite Local Sanidad Vegetal ID DOMINICAN AMBER; FRUIT-FLIES; TEPHRITIDAE; DIPTERA; AGE C1 Smithsonian Inst, USDA ARS, PSI, MRC 168,Systemat Entomol Lab, Washington, DC 20560 USA. RP Norrbom, AL (reprint author), Smithsonian Inst, USDA ARS, PSI, MRC 168,Systemat Entomol Lab, Washington, DC 20560 USA. NR 28 TC 1 Z9 1 U1 0 U2 0 PU CRC PRESS-TAYLOR & FRANCIS GROUP PI BOCA RATON PA 6000 BROKEN SOUND PARKWAY NW, STE 300, BOCA RATON, FL 33487-2742 USA BN 0-8493-1275-2 PY 2000 BP 135 EP 155 PG 21 WC Agronomy; Entomology SC Agriculture; Entomology GA BP56B UT WOS:000085492400007 ER PT B AU Norrbom, AL Zucchi, RA Hernandez-Ortiz, V AF Norrbom, AL Zucchi, RA Hernandez-Ortiz, V BE Aluja, M Norrbom, AL TI Phylogeny of the genera Anastrepha and Toxotrypana (Trypetinae : Toxotrypanini) based on morphology SO FRUIT FLIES (TEPHRITIDAE): PHYLOGENY AND EVOLUTION OF BEHAVIOR LA English DT Proceedings Paper CT Symposium Fruit Flies (Tephritidae) - Phylogeny and Evolution of Behavior CY FEB 16-21, 1998 CL VERACRUZ, MEXICO SP Campana Nacl Moscas Fruta, USDA, FAS, ICD, Div Res & Sci Exchanges, Int Org Biol Control Noxious Anim & Plants, Inst Ecol AC, Consejo Nacl Ciencia & Tecnol, Acad Mexicana Ciencias, Fdn Mexico Estados Unidos Ciencia, Comite Local Sanidad Vegetal ID IMMATURE STAGES; TEPHRITIDAE; DIPTERA; FRATERCULUS; SUSPENSA; REVISION; FLY C1 Smithsonian Inst, USDA ARS, PSI, MRC 168,Systemat Entomol Lab, Washington, DC 20560 USA. RP Norrbom, AL (reprint author), Smithsonian Inst, USDA ARS, PSI, MRC 168,Systemat Entomol Lab, Washington, DC 20560 USA. RI Zucchi, Roberto/D-7738-2012 OI Zucchi, Roberto/0000-0001-9861-7460 NR 67 TC 20 Z9 26 U1 0 U2 1 PU CRC PRESS-TAYLOR & FRANCIS GROUP PI BOCA RATON PA 6000 BROKEN SOUND PARKWAY NW, STE 300, BOCA RATON, FL 33487-2742 USA BN 0-8493-1275-2 PY 2000 BP 299 EP 342 PG 44 WC Agronomy; Entomology SC Agriculture; Entomology GA BP56B UT WOS:000085492400013 ER PT S AU Clougherty, DP AF Clougherty, DP BE Cohen, RE TI Ferroelectricity in (K@C-60)(n) SO FUNDAMENTAL PHYSICS OF FERROELECTRICS 2000 SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Aspen-Center-for-Physics Winter Workshop on Fundamental Physics of Ferroelectrics CY FEB 13-20, 2000 CL ASPEN, CO SP USN, Off Res, Carnegie Inst Washington, DARPA, Aspen Ctr Phys ID ENDOHEDRAL COMPLEXES; C-60 AB A theoretical analysis of the ground state of long-chain (K@C-60)(n), is presemed. Within mean field theory a ferroelectric ground state is found to be stable because of the pseudo-Jahn-Teller mixing of the B-1u and the b(2g) band with a zone-center optical phonon involving the displacement of the endohedral K+ ions. A phase diagram for this model is derived in the narrow bandwidth regime. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Clougherty, DP (reprint author), Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, 60 Garden St, Cambridge, MA 02138 USA. RI Clougherty, Dennis/A-4519-2008 OI Clougherty, Dennis/0000-0002-7299-4898 NR 12 TC 1 Z9 1 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-959-9 J9 AIP CONF PROC PY 2000 VL 535 BP 259 EP 265 PG 7 WC Physics, Condensed Matter SC Physics GA BR27C UT WOS:000165986600029 ER PT S AU McLeod, BA Conroy, M Gauron, TM Geary, JC Ordway, MP AF McLeod, BA Conroy, M Gauron, TM Geary, JC Ordway, MP BE Denton, MB TI Megacam: A wide-field imager for the MMT observatory SO FURTHER DEVELOPMENTS IN SCIENTIFIC OPTICAL IMAGING SE Royal Society of Chemistry Special Publications LA English DT Proceedings Paper CT 4th International Conference on Scientific Optical Imaging CY DEC 02-05, 1998 CL GEORGETOWN, W IND ASSOC ST ID CONVERTED MMT; SPECTROGRAPH C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP McLeod, BA (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 6 TC 12 Z9 12 U1 0 U2 0 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, CAMBRIDGE CB4 4WF, CAMBS, ENGLAND SN 0260-6291 BN 0-85404-784-0 J9 ROY SOC CH PY 2000 IS 254 BP 11 EP 17 DI 10.1039/9781847550958-00011 PG 5 WC Optics SC Optics GA BQ79Q UT WOS:000089544800003 ER PT S AU Geary, JC AF Geary, JC BE Denton, MB TI Signal processing for the SAO Megacam SO FURTHER DEVELOPMENTS IN SCIENTIFIC OPTICAL IMAGING SE ROYAL SOCIETY OF CHEMISTRY SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 4th International Conference on Scientific Optical Imaging CY DEC 02-05, 1998 CL GEORGETOWN, W IND ASSOC ST C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Geary, JC (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 2 TC 4 Z9 4 U1 0 U2 0 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, CAMBRIDGE CB4 4WF, CAMBS, ENGLAND SN 0260-6291 BN 0-85404-784-0 J9 ROY SOC CH PY 2000 IS 254 BP 18 EP 23 DI 10.1039/9781847550958-00018 PG 2 WC Optics SC Optics GA BQ79Q UT WOS:000089544800004 ER PT J AU Hau, M Wikelski, M Soma, KK Wingfield, JC AF Hau, M Wikelski, M Soma, KK Wingfield, JC TI Testosterone and year-round territorial aggression in a tropical bird SO GENERAL AND COMPARATIVE ENDOCRINOLOGY LA English DT Article DE aggressive behavior; hormonal regulation; steroid; androgen; song; territory; Spotted antbird ID MALE JAPANESE QUAIL; MOCKINGBIRDS MIMUS-POLYGLOTTOS; RED-WINGED BLACKBIRDS; BROWED SPARROW WEAVER; LOCOMOTOR-ACTIVITY; SEX STEROIDS; REPRODUCTIVE-BEHAVIOR; PLOCEPASSER-MAHALI; EUROPEAN ROBINS; MALE SONGBIRD AB Testosterone (T) regulates avian behaviors such as song and aggression during the breeding season. However, the role of T in year-round territorial birds is still enigmatic, especially in tropical birds. Spotted antbirds (Hylophylax n. naevioides) defend territories in the Panamanian rainforest year-round but have low plasma T levels (0.1-0.2 ng/ml), except during brief periods of social challenges. We manipulated T action in captive male Spotted antbirds to test whether this hormone is involved in the regulation of song and aggression. T-implants increased plasma androgen levels (T and dihydrotestosterone) and enhanced song in nonbreeding males. During a staged male-male encounter, T-implanted males sang more and were more aggressive than controls. In a second experiment, we blocked the two known T actions: its binding to androgen receptors and its conversion into estradiol by the enzyme aromatase. For this, we administered the androgen receptor antagonist flutamide (Flut) in combination with the aromatase inhibitor 1-4-6 androstatrien-3,17-dione (ATD) to birds in breeding condition. ATD + Flut treatment significantly elevated plasma levels of luteinizing hormone, presumably via the lack of T feedback from its receptors. ATD + Flut-treated birds gave fewer spontaneous songs than control-implanted males. During staged male-male encounters, ATD + Flut-treated males did not sing at all and showed reduced aggressive behavior. Our data indicate that T can regulate aggressive behavior in these tropical birds. Although plasma T levels can be low year-round, Spatted antbirds may use T either by secreting it briefly during social challenges, by having a high sensitivity to T action, or by enzymatically converting circulating T precursors directly at the site of action. We hypothesize that: plasma T levels are kept low in these year-round territorial birds to avoid potentially detrimental effects of tonically elevated T. Future treatment of nonbreeding birds with ATD + Flut will reveal whether T is indeed involved year-round in regulatin aggressive behavior. (C) 2000 Academic Press. C1 Univ Illinois, Dept Ecol Ethol & Evolut, Urbana, IL 61801 USA. Smithsonian Trop Res Inst, Balboa, Ancon, Panama. RP Hau, M (reprint author), Univ Illinois, Dept Ecol Ethol & Evolut, Urbana, IL 61801 USA. RI Soma, Kiran/B-9772-2012 OI Soma, Kiran/0000-0003-2169-8092 NR 84 TC 143 Z9 144 U1 1 U2 42 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0016-6480 J9 GEN COMP ENDOCR JI Gen. Comp. Endocrinol. PD JAN PY 2000 VL 117 IS 1 BP 20 EP 33 DI 10.1006/gcen.1999.7390 PG 14 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 285YU UT WOS:000085416600003 PM 10620421 ER PT J AU Krot, AN Petaev, MI Meibom, A Keil, K AF Krot, AN Petaev, MI Meibom, A Keil, K TI In situ growth of Ca-rich rims around allende dark inclusions SO GEOCHEMISTRY INTERNATIONAL LA English DT Article ID CV3 CHONDRITES; THERMAL METAMORPHISM; AQUEOUS ALTERATION; METEORITE; XENOLITH; ORIGIN AB Four heavily altered dark inclusions (4301-2, IV-1, 3b-1, IVa) in the Allende meteorite are composed exclusively of secondary minerals, including fayalitic olivine (Fa(40-45)), salitic pyroxenes (Fs(10-30)Wo(50)), nepheline, sodalite, and Fe-Ni sulfides. Chondrules in the dark inclusions are replaced by fayalitic olivine and nepheline. The chondrule pseudomorphs in 4301-2 and IVa are surrounded by salitic pyroxene rims which are commonly interconnected. Matrices of these dark inclusions are crosscut by multiple veins of salitic pyroxenes and Fe-Ni sulfides. The inclusions are surrounded by continuous Ca-Fe-rich rims with variable widths and show roughly symmetric mineralogic zoning. The innermost zone consists of diopside-salitic pyroxene (Fs(10-15)WO(48-50)) The central zone is composed of hedenbergite (Fs(48-50)Wo(48-50)), wollastonite (CaSiO3), andradite (Ca3Fe2Si3O12), and kirschsteinite (CaFeSiO4). The outermost zone consists of salite-hedenbergitic pyroxenes (Fs(15-35)Wo(48-50)) The rims are commonly intergrown with divine in the Allende matrix and enclose fragments of forsteritic olivine chondrules and lumps of the Allende-like matrix material. Abundant rounded objects composed of salite-hedenbergitic pyroxenes, andradite, and wollastonite ale observed in the Allende matrix near the Ca-rich rims. There are progressive Ca depletions from 4301-2 to IV-1 to 3b-1 to IVa. The degree of depletion correlates to the rim thicknesses, which increase in the same order. We conclude that the Allende dark inclusions experienced at least two stages of alteration in the presence of an aqueous solution after lithification and aggregation. One episode of alteration resulted in the replacement of primary chondrule minerals (forsterite, enstatite, anorthitic mesostasis, kamacite +/- troilite nodules) by secondary fayalitic olivine, nepheline, sodalite, and Ni-rich sulfides. Calcium removed from the chondrules was redeposited as salite-hedenbergitic pyroxene veins, as rounded objects in the matrix, and as rims around chondrules. Following this alteration, the dark inclusions were excavated from their original location (most likely the CV3 asteroidal body) and incorporated into the Allende host. The last episode of alteration took place in situ and resulted the in dissolution of Ca-Fe-rich pyroxenes in the dark inclusions and redeposition of Ca-rich minerals as rims around dark inclusions at the interfaces with the Allende host. The proposed mechanism of rim growth involves diffusional exchange of Ca and Fe between the dark inclusions and Allende, driven by the compositional difference between their matrix olivines. The precipitation of rim minerals started at similar to 250 degreesC at an iron-rich geochemical barrier (the Allende host), and continued at lower temperatures until the aqueous solution dried out. C1 Univ Hawaii Manoa, Hawaii Inst Geophys & Planetol, Sch Ocean & Earth Sci & Technol, Honolulu, HI 96822 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Stanford Univ, Stanford, CA 94305 USA. Hawaii Ctr Volcanol, Honolulu, HI USA. RP Krot, AN (reprint author), Univ Hawaii Manoa, Hawaii Inst Geophys & Planetol, Sch Ocean & Earth Sci & Technol, Honolulu, HI 96822 USA. NR 27 TC 6 Z9 6 U1 1 U2 2 PU INTERPERIODICA PI BIRMINGHAM PA PO BOX 1831, BIRMINGHAM, AL 35201-1831 USA SN 0016-7029 J9 GEOCHEM INT+ JI Geochem. Int. PY 2000 VL 38 SU 3 BP S351 EP S368 PG 18 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 401PK UT WOS:000166936300007 ER PT J AU Petaev, MI Clarke, RS Jarosewich, E Zaslavskaya, NI Kononkova, NN Wang, MS Lipschutz, ME Olsen, EJ Davis, AM Steele, IM Clayton, RN Mayeda, TK Kallemeyn, GW AF Petaev, MI Clarke, RS Jarosewich, E Zaslavskaya, NI Kononkova, NN Wang, MS Lipschutz, ME Olsen, EJ Davis, AM Steele, IM Clayton, RN Mayeda, TK Kallemeyn, GW TI The Chaunskij anomalous mesosiderite: Petrology, chemistry, oxygen isotopes, classification, and origin SO GEOCHEMISTRY INTERNATIONAL LA English DT Article ID METAMORPHIC REACTIONS; PALLASITE METEORITES; ORDINARY CHONDRITES; THERMAL HISTORY; CLASTS; DIOGENITES; PHOSPHATE; EUCRITES AB The Chaunskij meteorite, which was found in 1985 in northeastern Russia, consists of similar to 90 vol % metal and similar to 10% phosphate-silicate inclusions and sulfide nodules. Metallographic structures of the metal are consistent with a typical mesosiderite cooling history. The metal is unusually rich in Ni and depleted in W, Ir and Pt, and has been subjected to higher shock levels than metal in other mesosiderites. The phosphate-silicate inclusions contain three distinct lithologies that tend to replace one another. The primary igneous lithology: preserved only in the largest inclusions, consists of a fine-grained groundmass enclosing larger mineral and rock fragments and metal-sulfide droplets. The groundmass is an ophitic-to-xenomorphic aggregate of orthopyroxene (Fs(29.5)Wo(0.4)) and plagioclase (An(90.3)) With subordinate amounts of silica and minor or accessory whitlockite. chromite, ilmenite, rutile, troilite, and metal. The groundmass also contains numerous granoblastic zones enriched in troilite and quartz and depleted in pyroxene, which we treat as a separate granoblastic lithology. Abundant relict grains of pyroxene in both quartz and troilite indicate that granoblastic lithology has replaced the primary igneous lithology via the I reaction: Fe-rich Opx + S-2 --> Fe-poor Opx + FeS + Q + O-2. Truly metamorphic lithology which typically consists of a fine-grained hornfelsic-to-granoblastic aggregate of cordierite (mg# = 85), quartz, pyroxene, troilite, and whitlockite, occurs as small inclusions among the primary igneous lithology and among the host metal in larger inclusions. Tn the largest inclusion studied, cordierite sometimes forms millimeter-sized poikiloblasts enclosing small euhedral-to-subhedral troilite and quartz crystals, pyroxene relicts, and, rarely, intergrowths of pyroxene and plagioclase. Very close to the interface with the primary pyroxene-plagioclase rock, cordierite contains relicts of pyroxene and plagioclase, indicative of the substitution of the metamorphic lithology for the igneous one according to the reaction: Opx + Plag + P[ss in metal] + O-2 --> Cord + Qz + Whit. Thermodynamic analysis of the metamorphic reactions and mineral thermobarometry indicate that these reactions have proceeded simultaneously at similar to6 kbar total pressure and temperatures of 600-950 degreesC in the deep interior of a large parent body. Bulk chemical compositions of phosphate-silicate inclusions ale close to eucrites and mesosiderites, except for a large enrichment in P and volatile chalcophiles in Chaunskij. The oxygen isotope composition of the primary igneous lithology plots in the HED-Mes-Pal cluster; leaving no doubt as to the mesosideritic affinity of Chaunskij. The Chaunskij meteorite is classified as a type A mesosiderite, and is the most highly metamorphosed, shock-modified, and metal-rich example known. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Natl Museum Nat Hist, Dept Mineral Sci, Smithsonian Inst, Washington, DC 20560 USA. Russian Acad Sci, Vernadsky Inst Geochem & Analyt Chem, Moscow 117975, Russia. Purdue Univ, Dept Chem, W Lafayette, IN 47907 USA. Univ Chicago, Dept Geophys Sci, Chicago, IL 60637 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Univ Chicago, Dept Chem, Chicago, IL 60637 USA. Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90024 USA. RP Petaev, MI (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 66 TC 0 Z9 0 U1 1 U2 5 PU INTERPERIODICA PI BIRMINGHAM PA PO BOX 1831, BIRMINGHAM, AL 35201-1831 USA SN 0016-7029 J9 GEOCHEM INT+ JI Geochem. Int. PY 2000 VL 38 SU 3 BP S322 EP S350 PG 29 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 401PK UT WOS:000166936300006 ER PT J AU Reasoner, MA Jodry, MA AF Reasoner, MA Jodry, MA TI Rapid response of alpine timberline vegetation to the Younger Dryas climate oscillation in the Colorado Rocky Mountains, USA SO GEOLOGY LA English DT Article DE Younger Dryas; palynology; Rocky Mountains; rapid change; timberline ID SOUTHEASTERN ALASKA; LAST DEGLACIATION; NORTH-ATLANTIC; COOLING EVENT; CALIBRATION; AMERICA; RECORD; RANGE; END AB Paleobotanical records from two high-altitude (>3300 m) sites in Colorado show a clear and immediate response to the Younger Dryas climate oscillation. The Black Mountain Lake and Sky Pond records indicate that alpine timberline migrated upslope to near-modern elevations during the late Bolling-Allerod (13.6-12.9 ka). Subsequent declines in arboreal pollen percentages and accumulation rates during the Younger Dryas interval (12.9-11.7 ka) reflect a downslope displacement of the alpine timberline ecotone of 60-120 m in elevation. This change translates to a cooling of summer temperature by similar to 0.4-0.9 degrees C and is consistent,vith proposed Younger Dryas advances of alpine glaciers in the Rocky Mountains to positions close to Little Ice Age maxima. Alpine timberline readvanced upslope to elevations above both sites between 11.7 and 11.4 ka. The concomitant response of temperature-sensitive alpine timberline vegetation in Colorado and late-glacial changes in North Atlantic thermohaline circulation implicates a rapid, widespread atmospheric transmission of the Younger Dryas climate oscillation. C1 Univ Colorado, Inst Arctic & Alpine Res, Boulder, CO 80039 USA. Smithsonian Inst, Dept Anthropol, Paleoindian Paleoecol Program, Washington, DC 20560 USA. RP Reasoner, MA (reprint author), Univ Innsbruck, Inst Geog, Innrain 52, A-6020 Innsbruck, Austria. NR 35 TC 60 Z9 62 U1 1 U2 3 PU GEOLOGICAL SOC AMER, INC PI BOULDER PA PO BOX 9140, BOULDER, CO 80301-9140 USA SN 0091-7613 J9 GEOLOGY JI Geology PD JAN PY 2000 VL 28 IS 1 BP 51 EP 54 PG 4 WC Geology SC Geology GA 270ZZ UT WOS:000084568100013 ER PT S AU Weekes, TC AF Weekes, TC BE Dingus, BL Salamon, MH Kieda, DB TI VHE astronomy before the new millennium SO GEV-TEV GAMMA RAY ASTROPHYSICS WORKSHOP SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 6th Workshop on GeV-TeV Gamma Ray Astrophysics CY AUG 13-16, 1999 CL SNOWBIRD, UT SP Hamamatsu Corp, NASA ID ENERGY GAMMA-RAYS; ACTIVE GALAXY MARKARIAN-421; CRAB-NEBULA; TEV PHOTONS; X-RAY; DISCOVERY; EMISSION; BLAZARS C1 Harvard Smithsonian Ctr Astrophys, Whipple Observ, Amado, AZ 85645 USA. RP Weekes, TC (reprint author), Harvard Smithsonian Ctr Astrophys, Whipple Observ, POB 97, Amado, AZ 85645 USA. NR 61 TC 6 Z9 6 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-938-6 J9 AIP CONF PROC PY 2000 VL 515 BP 3 EP 15 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ39A UT WOS:000088226700001 ER PT S AU Vassiliev, VV AF Vassiliev, VV BE Dingus, BL Salamon, MH Kieda, DB TI Extragalactic background light absorption signal in the 0.26-10 TeV spectra of blazars SO GEV-TEV GAMMA RAY ASTROPHYSICS WORKSHOP SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 6th Workshop on GeV-TeV Gamma Ray Astrophysics CY AUG 13-16, 1999 CL SNOWBIRD, UT SP Hamamatsu Corp, NASA ID GAMMA-RAY ABSORPTION; GALAXY FORMATION; MARKARIAN-501 AB Recent observations of the TeV gamma-ray spectra of the two closest active galactic nuclei (AGNs), Markarian 501 (Mrk 501) and Markarian 421 (Mrk 421), by the Whipple and HEGRA collaborations have stimulated efforts to estimate or limit the spectral energy density (SED) of extragalactic background light (EBL) which causes attenuation of TeV photons via pair-production when they travel cosmological distances. In spite of the lack of any distinct cutoff-like feature in the spectra of Mrk 501 and Mrk 421 (in the interval 0.26 - 10 TeV) which could clearly indicate the presence of such a photon absorption mechanism, we demonstrate that strong EEL attenuation signal (survival probability of 10 TeV photon similar to 10(-2)) may still be present in the spectra of these AGNs. This attenuation could escape detection due to a special form of SED of EEL and unknown intrinsic spectra of these blazers. Here Ne show how the proposed and existing experiments, VERITAS, MESS, MAGIC, STACEE and CELESTE may be able to detect or severely limit the EEL SED by extension of spectral measurements into the critical 100 - 300 GeV regime. C1 Harvard Smithsonian Ctr Astrophys, Whipple Observ, Amado, AZ 85645 USA. RP Vassiliev, VV (reprint author), Harvard Smithsonian Ctr Astrophys, Whipple Observ, POB 97, Amado, AZ 85645 USA. NR 17 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-938-6 J9 AIP CONF PROC PY 2000 VL 515 BP 105 EP 110 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ39A UT WOS:000088226700014 ER PT S AU Fegan, SJ Bond, IH Bradbury, SM Breslin, AC Buckley, JH Burdett, AM Carson, M Carter-Lewis, DA Catanese, M Cawley, MF Dunlea, S D'Vali, M Fegan, DJ Finley, JP Gaidos, JA Hall, TA Hillas, AM Horan, D Knapp, J Krennrich, F Le Bohec, S Lessard, RW Masterson, C McKernan, B Quinn, J Rose, HJ Samuelson, FW Sembroski, GH Vassiliev, VV Weekes, TC AF Fegan, SJ Bond, IH Bradbury, SM Breslin, AC Buckley, JH Burdett, AM Carson, M Carter-Lewis, DA Catanese, M Cawley, MF Dunlea, S D'Vali, M Fegan, DJ Finley, JP Gaidos, JA Hall, TA Hillas, AM Horan, D Knapp, J Krennrich, F Le Bohec, S Lessard, RW Masterson, C McKernan, B Quinn, J Rose, HJ Samuelson, FW Sembroski, GH Vassiliev, VV Weekes, TC BE Dingus, BL Salamon, MH Kieda, DB TI Periodicity analysis of Markarian 501 flaring activity in 1997 SO GEV-TEV GAMMA RAY ASTROPHYSICS WORKSHOP SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 6th Workshop on GeV-TeV Gamma Ray Astrophysics CY AUG 13-16, 1999 CL SNOWBIRD, UT SP Hamamatsu Corp, NASA AB We report on a periodicity analysis of gamma-ray observations of very high energy (VHE, E > 250GeV) gamma-rays from Markarian 501 (Mrk 501) taken with the Whipple telescope between March and July of 1997. The data correspond to a period of bright flaring of the source, quasi-periodic signals were detected by the Telescope Array Project (TAP) and HEGRA collaboration. Periodic analysis of these data is complicated because the source observations are not continuous and the reported period (approximate to 24 days) is very close to the sampling period. We use the Lomb method, a technique for extracting spectral information from unevenly sampled data, in an attempt to overcome this difficulty. Similar results are shown to exist in data from the strongly correlated X-ray band sampled by the RXTE ASM instrument. No periodicity in the data could be identified with a source frequency. C1 Harvard Smithsonian Ctr Astrophys, Fred Lawrence Whipple Observ, Amado, AZ 85645 USA. RP Fegan, SJ (reprint author), Harvard Smithsonian Ctr Astrophys, Fred Lawrence Whipple Observ, Amado, AZ 85645 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-938-6 J9 AIP CONF PROC PY 2000 VL 515 BP 129 EP 133 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ39A UT WOS:000088226700018 ER PT S AU Kalogera, V AF Kalogera, V BE Meshkov, S TI Compact binary mergers and accretion-induced collapse: Event rates SO GRAVITATIONAL WAVES SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 3rd Edoardo Amaldi Conference on Gravitational Waves CY JUL 12-16, 1999 CL CALTECH, PASADENA, CA SP Caltech, Dept Phys Math & Astron, US Natl Sci Fdn, Ist Nazl Fis Nucleare, Parsons Corp, Lightwave Electr HO CALTECH ID NEUTRON-STAR BINARIES; GRAVITATIONAL-RADIATION; WHITE-DWARFS; PULSAR; SYSTEM; KICKS AB This paper is a brief review of the topic of binary systems as sources of gravitational-wave emission for both LIGO and LISA. In particular I review the current estimates of the associated Galactic event rates and their implications for expected detection rates. I discuss the estimates for (i) the coalescence of close binaries containing neutron stars or black holes, (ii) white dwarfs going through accretion-induced collapse into neutron stars, and (iii) detached but close binaries containing two white dwarfs. The relevant uncertainties and robustness of the estimates are addressed dong with ways of obtaining conservative upper limits. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Kalogera, V (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 33 TC 5 Z9 5 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-944-0 J9 AIP CONF PROC PY 2000 VL 523 BP 41 EP 50 PG 10 WC Astronomy & Astrophysics; Optics SC Astronomy & Astrophysics; Optics GA BQ56Y UT WOS:000088786300003 ER PT S AU Houser, JL AF Houser, JL BE Meshkov, S TI Instabilities in stiff stellar cores: The gravitational radiation reaction SO GRAVITATIONAL WAVES SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 3rd Edoardo Amaldi Conference on Gravitational Waves CY JUL 12-16, 1999 CL CALTECH, PASADENA, CA SP Caltech, Dept Phys Math & Astron, US Natl Sci Fdn, Ist Nazl Fis Nucleare, Parsons Corp, Lightwave Electr HO CALTECH ID NONAXISYMMETRIC INSTABILITY; PARTICLE HYDRODYNAMICS; NEUTRON-STARS; ROTATING STAR AB Symmetry-breaking rotational instabilities may play a significant role in the dynamics of rapidly rotating compact objects. During the growth of such global non-axisymmetric instabilities, the external spacetime undergoes dynamical changes in response to the changing shape of the object and gravitational radiation is emitted. Using a three-dimensional Smoothed Particle Hydrodynamics code, the numerically generated gravitational wave signals of two pre-supernova stellar cores undergoing a dynamical instability will be compared. The first model assumes a purely Newtonian gravitational field, while the second model incorporates the General Relativistic "back reaction" into the hydrodynamical equations. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Houser, JL (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 18 TC 0 Z9 0 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-944-0 J9 AIP CONF PROC PY 2000 VL 523 BP 51 EP 54 PG 4 WC Astronomy & Astrophysics; Optics SC Astronomy & Astrophysics; Optics GA BQ56Y UT WOS:000088786300004 ER PT S AU Narita, T Bloser, PF Grindlay, JE Jenkins, JA AF Narita, T Bloser, PF Grindlay, JE Jenkins, JA BE James, RB Schirato, RC TI Development of gold contacted flip-chip detectors with IMARAD CZT SO HARD X-RAY GAMMA-RAY AND NEUTRON DETECTOR PHYSICS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Hard X-Ray, Gamma-Ray, and Neutron Detector Physics CY JUL 31-AUG 02, 2000 CL SAN DIEGO, CA SP SPIE DE CdZnTe; pixellated imaging detectors; hard X-ray imaging AB We present initial results from our evaluation of a gold-contacted pixellated detector using cadmium zinc telluride substrate produced by IMARAD Imaging Systems. The Horizontal Bridgman (HB) grown crystals from IMARAD have been shown to produce high resolution photopeaks, but they are also seen to have large leakage current. Our previous tests with IMARAD CZT showed that the use of indium anodes and gold cathode improved the resistivity compared to the standard indium-contacted detectors. We seek to test whether simple evaporated gold contacts alone could also reduce the leakage current and thus improve the spectral resolution, especially in the 10-100 keV energy range. We have fabricated several metal-semiconductor-metal (MSM) detectors with a 4 x 4 array of pixels on 10 x 10 mm substrates. Measurements of the detectors' leakage current, spectral response, and temperature sensitivity are presented and compared to IMARAD's ohmic contact detector and gold contact MSM detectors made of High Pressure Bridgman (HPB) material. Finally, we show preliminary results from a tiled flip-chip pixellated detector made using the IMARAD detectors. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Narita, T (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 10 TC 10 Z9 10 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3786-7 J9 P SOC PHOTO-OPT INS PY 2000 VL 4141 BP 89 EP 96 DI 10.1117/12.407569 PG 8 WC Instruments & Instrumentation; Optics; Physics, Multidisciplinary; Physics, Condensed Matter SC Instruments & Instrumentation; Optics; Physics GA BR62H UT WOS:000166964500009 ER PT S AU Remo, JL Hammerling, P AF Remo, JL Hammerling, P BE Phipps, CR TI Experimental and computational results for 1054nm laser induced shock effects in confined meteorite and metallic targets SO HIGH-POWER LASER ABLATION III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on High-Power Laser Ablation III CY APR 24-28, 2000 CL SANTA FE, NM SP SPIE, Anteon Corp, Coherent Technologies Inc, Los Alamos Natl Lab, Photon Assoc Inc DE laser coupling; shock waves; impulse; tamping; LSD wave ID DRIVEN SPALLATION PROCESS; INTERFEROMETRY TECHNIQUE; PLASMA; PRESSURE; GEOMETRY; WAVES AB When a single-pulse high-power laser irradiates a surface at atmospheric pressure, a laser supported detonation (LSD) wave can form above the target surface. The high-pressure gas behind the LSD wave transfers momentum to the target. The laser target coupling is substantially reduced in vacuum, the coupling coefficient typically being an order of magnitude less than that when an atmosphere is present. Another pressure enhancement technique is to confine the laser-target interface. Confinement or "tamping" also can substantially increase the momentum coupling to the target. Experiments tend to differ from one another based confine the target size (thickness) and confinement geometry. This work describes and compares some experimental results for metallic targets irradiated by 1054 nm radiation in the GW/cm(2) range and interprets them in terms of simple models. As will be discussed in this paper, such models predict a weak sensitivity to target materials but results are likely to be different for inhomogeneous materials as has been seen in recent experiments on iron-nickel and stony meteorites. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Remo, JL (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 14 TC 0 Z9 0 U1 1 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3700-X J9 P SOC PHOTO-OPT INS PY 2000 VL 4065 BP 635 EP 643 DI 10.1117/12.407384 PG 9 WC Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BQ88B UT WOS:000089914200062 ER PT S AU White, NE Tananbaum, H AF White, NE Tananbaum, H BE Martens, PCH Tsuruta, S Weber, MA TI The Constellation X-ray mission SO HIGHLY ENERGETIC PHYSICAL PROCESSES AND MECHANISMS FOR EMISSION FROM ASTROPHYSICAL PLASMAS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 195th Symposium of the International-Astronomical-Union CY JUL 06-10, 1999 CL MONTANA STATE UNIV BOZEMAN, BOZEMAN, MONTANA SP Int Astron Union, NASA, NSF HO MONTANA STATE UNIV BOZEMAN AB The Constellation-X mission is a large collecting-area X-ray facility emphasizing observations at high spectral resolution (E/DeltaE similar to 300-3000) while covering a broad energy band (0.25-40 keV). By increasing the telescope aperture and utilizing efficient spectrometers, the mission will achieve a factor of 100 increased sensitivity over current high-resolution X-ray spectroscopy missions. The use of focusing optics across the 10-40 keV band will provide a similar factor of 100 increased sensitivity in this band. When observations commence in similar to 2008, Constellation-X will address many pressing questions concerning the extremes of gravity and the evolution of the Universe. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP White, NE (reprint author), NASA, Goddard Space Flight Ctr, Code 662, Greenbelt, MD 20771 USA. RI White, Nicholas/B-6428-2012 OI White, Nicholas/0000-0003-3853-3462 NR 9 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 0074-1809 BN 1-58381-038-2 J9 IAU SYMP PY 2000 IS 195 BP 61 EP 68 PG 8 WC Astronomy & Astrophysics; Physics, Fluids & Plasmas SC Astronomy & Astrophysics; Physics GA BU35P UT WOS:000175748200006 ER PT S AU Audard, M Gudel, M Drake, JJ Kashyap, V Guinan, EF AF Audard, M Gudel, M Drake, JJ Kashyap, V Guinan, EF BE Martens, PCH Tsuruta, S Weber, MA TI Active late-type stellar coronae: Hints for flare heating? SO HIGHLY ENERGETIC PHYSICAL PROCESSES AND MECHANISMS FOR EMISSION FROM ASTROPHYSICAL PLASMAS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 195th Symposium of the International-Astronomical-Union CY JUL 06-10, 1999 CL MONTANA STATE UNIV BOZEMAN, BOZEMAN, MONTANA SP Int Astron Union, NASA, NSF HO MONTANA STATE UNIV BOZEMAN ID NANOFLARES AB The Extreme Ultraviolet Explorer data archive has been used to study flare energy distributions and infer the role of flares in coronal heating. We have constructed flare number distributions as a function of observed EUV and X-ray emitted thermal energy. We find cumulative flare distributions of the form N(> E) proportional to E-alpha+1 with alpha approximate to 1.5-2.6. We present results in the context of spectral type classification. C1 Paul Scherrer Inst, PSI, CH-5232 Villigen, Switzerland. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Villanova Univ, Dept Astron & Astrophys, Villanova, PA 19085 USA. ETH Zentrum, Astron Inst, CH-8092 Zurich, Switzerland. RP Audard, M (reprint author), Paul Scherrer Inst, PSI, CH-5232 Villigen, Switzerland. RI Guedel, Manuel/C-8486-2015 OI Guedel, Manuel/0000-0001-9818-0588 NR 6 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 0074-1809 BN 1-58381-038-2 J9 IAU SYMP PY 2000 IS 195 BP 377 EP 378 PG 2 WC Astronomy & Astrophysics; Physics, Fluids & Plasmas SC Astronomy & Astrophysics; Physics GA BU35P UT WOS:000175748200045 ER PT S AU Di Matteo, T Allen, SW AF Di Matteo, T Allen, SW BE Martens, PCH Tsuruta, S Weber, MA TI X-ray emission from supermassive black holes in elliptical galaxies and low radiative-efficiency accretion SO HIGHLY ENERGETIC PHYSICAL PROCESSES AND MECHANISMS FOR EMISSION FROM ASTROPHYSICAL PLASMAS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 195th Symposium of the International-Astronomical-Union CY JUL 06-10, 1999 CL MONTANA STATE UNIV BOZEMAN, BOZEMAN, MONTANA SP Int Astron Union, NASA, NSF HO MONTANA STATE UNIV BOZEMAN AB We discuss the detection of hard, power-law emission components in the X-ray spectra of six nearby, giant elliptical galaxies observed with the ASCA satellite and its implication for low-radiative efficiency accretion models around the central, supermassive black holes. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Astron Inst, Cambridge CB3 0HA, England. RP Di Matteo, T (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 3 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 0074-1809 BN 1-58381-038-2 J9 IAU SYMP PY 2000 IS 195 BP 387 EP 388 PG 2 WC Astronomy & Astrophysics; Physics, Fluids & Plasmas SC Astronomy & Astrophysics; Physics GA BU35P UT WOS:000175748200049 ER PT S AU Field, GB Blackman, EG AF Field, GB Blackman, EG BE Martens, PCH Tsuruta, S Weber, MA TI Magnetic helicity, dynamo action, reconnection, and particle acceleration SO HIGHLY ENERGETIC PHYSICAL PROCESSES AND MECHANISMS FOR EMISSION FROM ASTROPHYSICAL PLASMAS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 195th Symposium of the International-Astronomical-Union CY JUL 06-10, 1999 CL MONTANA STATE UNIV BOZEMAN, BOZEMAN, MONTANA SP Int Astron Union, NASA, NSF HO MONTANA STATE UNIV BOZEMAN ID TURBULENCE AB Blackman & Field have shown that a working alpha-Omega dynamo requires finite but opposite flows of small- and large-scale magnetic helicity through a body's surface. The helicity is accompanied by magnetic energy available for dissipation. The observed solar coronal nonthermal power is consistent with the derived lower limit required. This link between dynamo field generation and nonthermal emission should generally apply to stars, spiral galaxies, and accretion disks. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CALTECH, Pasadena, CA 91125 USA. RP Field, GB (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 12 TC 0 Z9 0 U1 0 U2 1 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA SN 0074-1809 BN 1-58381-038-2 J9 IAU SYMP PY 2000 IS 195 BP 389 EP 390 PG 2 WC Astronomy & Astrophysics; Physics, Fluids & Plasmas SC Astronomy & Astrophysics; Physics GA BU35P UT WOS:000175748200050 ER PT S AU Field, GB AF Field, GB BE Martens, PCH Tsuruta, S Weber, MA TI Symposium summary and concluding remarks SO HIGHLY ENERGETIC PHYSICAL PROCESSES AND MECHANISMS FOR EMISSION FROM ASTROPHYSICAL PLASMAS SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 195th Symposium of the International-Astronomical-Union CY JUL 06-10, 1999 CL MONTANA STATE UNIV BOZEMAN, BOZEMAN, MONTANA SP Int Astron Union, NASA, NSF HO MONTANA STATE UNIV BOZEMAN AB The symposium included invited papers, a panel discussion, and poster papers. In the following, I have summarized what to me were some of the more interesting parts of invited papers under the headings of trends, particle acceleration and heating, disks and jets, gamma-ray bursts, and other sources. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Field, GB (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 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 0074-1809 BN 1-58381-038-2 J9 IAU SYMP PY 2000 IS 195 BP 485 EP 488 PG 4 WC Astronomy & Astrophysics; Physics, Fluids & Plasmas SC Astronomy & Astrophysics; Physics GA BU35P UT WOS:000175748200080 ER PT J AU Devorkin, DH AF Devorkin, DH TI Who speaks for astronomy? How astronomers responded to government funding after World War II SO HISTORICAL STUDIES IN THE PHYSICAL AND BIOLOGICAL SCIENCES LA English DT Review ID ACADEMIC SCIENCE C1 Smithsonian Inst, Natl Air & Space Museum, Div Space Hist, Washington, DC 20560 USA. RP Devorkin, DH (reprint author), Smithsonian Inst, Natl Air & Space Museum, Div Space Hist, Room 3530, Washington, DC 20560 USA. NR 153 TC 9 Z9 9 U1 0 U2 2 PU UNIV CALIF PRESS PI BERKELEY PA C/O JOURNALS DIVISION, 2000 CENTER ST, STE 303, BERKELEY, CA 94704-1223 USA SN 0890-9997 J9 HIST STUD PHYS BIOL JI Hist. Stud. Phys. Biol. Sci. PY 2000 VL 31 BP 55 EP 92 PN 1 PG 38 WC History & Philosophy Of Science SC History & Philosophy of Science GA 395NF UT WOS:000166585900003 ER PT J AU Hacker, BC AF Hacker, BC TI Military patronage and the geophysical sciences in the United States: An introduction SO HISTORICAL STUDIES IN THE PHYSICAL AND BIOLOGICAL SCIENCES LA English DT Article; Proceedings Paper CT Meeting of the American-Geophysical-Union CY 1998 CL BOSTON, MASSACHUSETTS SP Amer Geophys Union C1 Smithsonian Inst, Washington, DC 20560 USA. RP Hacker, BC (reprint author), Smithsonian Inst, NMAH-4013, Washington, DC 20560 USA. NR 0 TC 6 Z9 7 U1 0 U2 0 PU UNIV CALIF PRESS PI BERKELEY PA C/O JOURNALS DIVISION, 2000 CENTER ST, STE 303, BERKELEY, CA 94704-1223 USA SN 0890-9997 J9 HIST STUD PHYS BIOL JI Hist. Stud. Phys. Biol. Sci. PY 2000 VL 30 BP 309 EP 313 PN 2 PG 5 WC History & Philosophy Of Science SC History & Philosophy of Science GA 349UW UT WOS:000089064800002 ER PT J AU Warner, DJ AF Warner, DJ TI From Tallahassee to Timbuktu: Cold War efforts to measure intercontinental distances SO HISTORICAL STUDIES IN THE PHYSICAL AND BIOLOGICAL SCIENCES LA English DT Article; Proceedings Paper CT Meeting of the American-Geophysical-Union CY 1998 CL BOSTON, MASSACHUSETTS SP Amer Geophys Union C1 Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. RP Warner, DJ (reprint author), Smithsonian Inst, Natl Museum Amer Hist, 5128-A, Washington, DC 20560 USA. NR 191 TC 9 Z9 9 U1 0 U2 0 PU UNIV CALIF PRESS PI BERKELEY PA C/O JOURNALS DIVISION, 2000 CENTER ST, STE 303, BERKELEY, CA 94704-1223 USA SN 0890-9997 J9 HIST STUD PHYS BIOL JI Hist. Stud. Phys. Biol. Sci. PY 2000 VL 30 BP 393 EP 415 PN 2 PG 23 WC History & Philosophy Of Science SC History & Philosophy of Science GA 349UW UT WOS:000089064800007 ER PT J AU Gossel, PP AF Gossel, PP TI Pasteur, Koch and American bacteriology SO HISTORY AND PHILOSOPHY OF THE LIFE SCIENCES LA English DT Article; Proceedings Paper CT Conference on Pasteur, Germs and the Bacterial Laboratory CY NOV 22-23, 1996 CL MIT, DIBNER INST HIST SCI & TECHNOL, CAMBRIDGE, MASSACHUSETTS HO MIT, DIBNER INST HIST SCI & TECHNOL AB This study traces American awareness of the work of Louis Pasteur and Robert Koch from the 1860s to the 1890s. In the years before the Civil War, American interest in germ theories had appeared at times of epidemics and persisted to a limited extent among physician-microscopists. Discussions of Pasteur's work occurred primarily in the context of spontaneous generation and antisepsis. Few Americans imitated his work on immunology or studied with Pasteur, but his work on immunity influenced their faith in the potential of bacteriology as a solution to problems of infectious disease. Koch's discoveries of the bacterial agents of tuberculosis and cholera stimulated American medical and public health interest in bacteriology in a more practical way. Americans learned Koch's methods by taking his courses and imported them directly into their own laboratories. A context of enthusiasm for science, educational reform, and problems of infectious disease associated with urbanization and changes in agriculture aided the growth of bacteriology in the American context. C1 Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. RP Gossel, PP (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. NR 99 TC 0 Z9 0 U1 0 U2 5 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0391-9714 J9 HIST PHIL LIFE SCI JI Hist. Philos. Life Sci. PY 2000 VL 22 IS 1 BP 81 EP 100 PG 20 WC History & Philosophy Of Science SC History & Philosophy of Science GA 406WX UT WOS:000167240100005 PM 11258102 ER PT J AU Alekseev, V Wyngaard, GA Ferrari, FD AF Alekseev, V Wyngaard, GA Ferrari, FD TI Untitled - Preface SO HYDROBIOLOGIA LA English DT Editorial Material C1 RAS, Inst Zool, St Petersburg, Russia. James Madison Univ, Harrisonburg, VA 22807 USA. Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. RP Alekseev, V (reprint author), RAS, Inst Zool, St Petersburg, Russia. NR 0 TC 1 Z9 1 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0018-8158 J9 HYDROBIOLOGIA JI Hydrobiologia PD JAN PY 2000 VL 417 BP VII EP VIII PG 2 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 295YA UT WOS:000085995200001 ER PT J AU Ferrari, FD AF Ferrari, FD TI Patterns of setal numbers conserved during early development of swimming legs of Copepoda (Crustacea) SO HYDROBIOLOGIA LA English DT Article; Proceedings Paper CT Conference to Honor Ulrich Einsle and Celebrate his Lifelong Contributions to Copepod Biology CY MAY, 1998 CL ST PETERSBURG, RUSSIA SP World Assoc Copepodologists, Hermitage Museum, Restorant Academia, Russian Hydrobiol Soc, State Sci Fdn Integrat DE copepod; swimming leg; setation; development ID SEGMENTS AB During swimming leg development, the number of setae present on the exopod and endopod of the bilobed bud, the transformed swimming leg with 1-segmented rami and the swimming leg with 2-segmented rami of copepods is analysed. For swimming leg 1, the most frequent number of setae on the presumptive rami of the bilobed bud is found at a higher percentage among copepod species than the most frequent number of setae for either the transformed swimming leg with 1-segmented rami or the swimming leg with 2-segmented rami. However, for swimming legs 2-4 the most frequent number of setae for the the transformed swimming leg with 1-segmented rami is found at a higher percentage of species than that on either the bilobed bud or the swimming leg with 2-segmented rami. Thus, in the cases of swimming legs 2-4, species with different numbers of setae on the presumptive exopod and endopod of the bud bilobed bud develop the same number of setae on the rami of the transformed swimming leg with 1-segmented rami. Increasing the number of species analysed is expected to make more robust the hypothesis that the number of setae on the transformed swimming leg with 1-segmented rami is conserved relative to the number of setae on the bilobed bud. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Ferrari, FD (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. NR 4 TC 11 Z9 12 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0018-8158 J9 HYDROBIOLOGIA JI Hydrobiologia PD JAN PY 2000 VL 417 BP 81 EP 90 DI 10.1023/A:1003895004611 PG 10 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 295YA UT WOS:000085995200008 ER PT S AU Shaw, C AF Shaw, C BE Markham, JW Duda, AL TI Entrez and transgenic fish: Exploring genomic databases on the Web SO IAMSLIC 99: RECASTING THE NETS SE INTERNATIONAL ASSOCIATION OF AQUATIC AND MARINE SCIENCE, LIBRARIES AND INFORMATION CONFERENCE SERIES LA English DT Proceedings Paper CT 25th Annual Conference of the International-Association-of-Aquatic-and-Marine-Science-Libraries-and-In formation-Centers CY OCT 16-22, 1999 CL WOODS HOLE, MA SP Int Assoc Aquat & Marine Sci Lib Informat Ctr AB In today's world the literature is full of articles on the human genome, gene therapy, and transgenic plants. At the Smithsonian, especially at the Laboratory for Molecular Systematics researchers are looking at tissue samples for their DNA and submitting information into Genbank.Lectures on storing them have been given at Society for the Study of Natural History Collections (SPNHC). At the National Zoological Park through NOAHS (New Opportunities in the Health Sciences) gene pools are being broadened through artificial insemination. Moreover, as the zoologists present their papers at conferences and write their articles often there are comparative references of morphological and visual studies to their genetic components. At the Smithsonian and everywhere sequence data has been integrated into others forms of research. Thus, I wish to inform those librarians who might not be that familiar with the genomic databases about them. C1 Natl Museum Nat Hist, Smithsonian Inst Lib, Washington, DC 20560 USA. RP Shaw, C (reprint author), Natl Museum Nat Hist, Smithsonian Inst Lib, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU INT ASSOC MARINE SCIENCE LIBRARIES & INFORMATION CENTER PI FORT PIERCE PA C/O HBOI LIBRARY, 5600 OLD DIXIE HWY, FORT PIERCE, FL 34946 USA SN 8755-6332 J9 IAMSLIC C S PY 2000 BP 117 EP 118 PG 2 WC Computer Science, Interdisciplinary Applications; Information Science & Library Science; Marine & Freshwater Biology SC Computer Science; Information Science & Library Science; Marine & Freshwater Biology GA BQ36Q UT WOS:000088143000013 ER PT B AU Lee, Y Kim, HG Moon, DS Stark, AA AF Lee, Y Kim, HG Moon, DS Stark, AA BE Mangum, JG Radford, SJE TI A galactic plane (CO)-C-13 survey SO IMAGING AT RADIO THROUGH SUBMILLIMETER WAVELENGTHS, PROCEEDINGS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on Imaging at Radio Through Submillimeter Wavelengths (Imaging 99) CY JUN 06-09, 1999 CL TUCSON, AZ ID MOLECULAR CLOUDS; CO SURVEY; GALAXY C1 Harvard Smithsonian Ctr Astrophys, CfA, Cambridge, MA 02138 USA. RP Lee, Y (reprint author), Harvard Smithsonian Ctr Astrophys, CfA, 60 Garden St, Cambridge, MA 02138 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-049-8 J9 ASTR SOC P PY 2000 VL 217 BP 80 EP 81 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BR93Y UT WOS:000168121900016 ER PT B AU Ho, PTP AF Ho, PTP BE Mangum, JG Radford, SJE TI The Submillimeter Array project SO IMAGING AT RADIO THROUGH SUBMILLIMETER WAVELENGTHS, PROCEEDINGS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on Imaging at Radio Through Submillimeter Wavelengths (Imaging 99) CY JUN 06-09, 1999 CL TUCSON, AZ AB The Submillimeter Array is a collaboration between the Smithsonian Astrophysical Observatory and the Institute of Astronomy and Astrophysics in Taiwan. A total of eight antennas are being constructed on Mauna Kea. A number of major milestones were achieved in the past year, including the detection of first fringes on Saturn at 230 GHz in October 1998 with the first two antennas at Westford, Massachusetts, and the arrival of the first antenna mount on Mauna Kea in April 1999. We report on the latest status of the project and what we aim to achieve in the next year. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Ho, PTP (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 0 TC 5 Z9 5 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-049-8 J9 ASTR SOC P PY 2000 VL 217 BP 227 EP 234 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BR93Y UT WOS:000168121900049 ER PT B AU Wiedner, MC Hills, RE AF Wiedner, MC Hills, RE BE Mangum, JG Radford, SJE TI Phase correction on Mauna Kea using 183 GHz water vapor monitors SO IMAGING AT RADIO THROUGH SUBMILLIMETER WAVELENGTHS, PROCEEDINGS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on Imaging at Radio Through Submillimeter Wavelengths (Imaging 99) CY JUN 06-09, 1999 CL TUCSON, AZ AB One of the major challenges in millimeter and submillimeter interferometry is to correct for phase fluctuations caused by atmospheric water vapor. Of the many possible phase correction methods, the use of radiometers which monitor the water vapor transition line at 183 GHz is one of the most promising. Two radiometers have been built and mounted on the CSO and the JCMT. These instruments are described and recent results from tests on the JCMT-CSO interferometer are presented. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Wiedner, MC (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS 78, Cambridge, MA 02138 USA. NR 9 TC 4 Z9 4 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-049-8 J9 ASTR SOC P PY 2000 VL 217 BP 327 EP 335 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BR93Y UT WOS:000168121900062 ER PT B AU Szentgyorgyi, A Stanek, KZ Sasselov, D Kaluzny, J Schwarzenberg-Czerny, A AF Szentgyorgyi, A Stanek, KZ Sasselov, D Kaluzny, J Schwarzenberg-Czerny, A BE Szabados, L Kurtz, DW TI A synoptic variability survey of M3 SO IMPACT OF LARGE-SCALE SURVEYS ON PULSATING STAR RESEARCH SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 176th IAU Colloquium on the Impact of Large-Scale Surveys on Pulsating Star Research CY AUG 08-12, 1999 CL BUDAPEST, HUNGARY SP Int Astron Union, Int Union Pure & Appl Phys, Hungarian Acad Sci, Natl Comm Technol Dev, Hungarian Sci Res Fund, Silicon Graph Inc, Sun Microsyst Magyarorszag Kft, Blackwell Sci Ltd ID DETACHED ECLIPSING BINARIES; DIRECT DISTANCES; VARIABLES; CEPHEIDS; SEARCH; STARS AB We present preliminary results from a synoptic photometric variability survey of the galactic globular cluster M3. These data consist of between 9 and 13 nights of data, the sampling allows a minimum detectable period of 10 minutes and is complete to M-V similar to 21. C1 Harvard Smithsonian Ctr Astrophys, Opt & Infrared Div, Cambridge, MA 02138 USA. RP Szentgyorgyi, A (reprint author), Harvard Smithsonian Ctr Astrophys, Opt & Infrared Div, 60 Garden St, Cambridge, MA 02138 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-030-7 J9 ASTR SOC P PY 2000 VL 203 BP 161 EP 164 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ80M UT WOS:000089620700050 ER PT B AU Sasselov, DD AF Sasselov, DD BE Szabados, L Kurtz, DW TI DIRECT distances to local group galaxies SO IMPACT OF LARGE-SCALE SURVEYS ON PULSATING STAR RESEARCH SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 176th IAU Colloquium on the Impact of Large-Scale Surveys on Pulsating Star Research CY AUG 08-12, 1999 CL BUDAPEST, HUNGARY SP Int Astron Union, Int Union Pure & Appl Phys, Hungarian Acad Sci, Natl Comm Technol Dev, Hungarian Sci Res Fund, Silicon Graph Inc, Sun Microsyst Magyarorszag Kft, Blackwell Sci Ltd ID DETACHED ECLIPSING BINARIES; VARIABLES; CEPHEIDS AB The two nearby galaxies, M31 and M33, are stepping stones for most of our current efforts to understand the evolving universe at large scales. We are undertaking a long term project, called DIRECT, to improve the direct distance estimate to M31 and M33. The massive photometry we have obtained as part of our project over the past 3 years provides us with very good light curves for known and new Cepheid variables, a large number of eclipsing binaries and other variable stars. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Sasselov, DD (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-030-7 J9 ASTR SOC P PY 2000 VL 203 BP 182 EP 186 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ80M UT WOS:000089620700054 ER PT B AU Evans, NR Carpenter, K Robinson, R Massa, D Wahlgren, GM Vinko, J Szabados, L AF Evans, NR Carpenter, K Robinson, R Massa, D Wahlgren, GM Vinko, J Szabados, L BE Szabados, L Kurtz, DW TI Critical complements: Progress on the orbit of T Mon SO IMPACT OF LARGE-SCALE SURVEYS ON PULSATING STAR RESEARCH SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 176th IAU Colloquium on the Impact of Large-Scale Surveys on Pulsating Star Research CY AUG 08-12, 1999 CL BUDAPEST, HUNGARY SP Int Astron Union, Int Union Pure & Appl Phys, Hungarian Acad Sci, Natl Comm Technol Dev, Hungarian Sci Res Fund, Silicon Graph Inc, Sun Microsyst Magyarorszag Kft, Blackwell Sci Ltd AB A preliminary orbit has been derived for the high luminosity, 27-d classical Cepheid T Mon. Velocities for the hot companion have been measured from an HST GHRS spectrum and 3 IUE spectra. The companion velocities are inconsistent with binary orbital motion and it is likely that the companion is itself a short period binary. The HST spectrum also shows that the companion is a chemically peculiar star, probably magnetic. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Evans, NR (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Carpenter, Kenneth/D-4740-2012 NR 1 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-030-7 J9 ASTR SOC P PY 2000 VL 203 BP 246 EP 247 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ80M UT WOS:000089620700072 ER PT S AU Hora, JL Fazio, GG Willner, SP Ashby, MLN Huang, JS Megeath, ST Stauffer, J Tollestrup, EV Wang, Z Glaccum, W Pipher, JL Forrest, WJ McCreight, CR McKelvey, M Hoffmann, WF Eisenhardt, P Surace, JA Reach, W Moseley, SH Arendt, R Stewart, KP Robinson, FD AF Hora, JL Fazio, GG Willner, SP Ashby, MLN Huang, JS Megeath, ST Stauffer, J Tollestrup, EV Wang, Z Glaccum, W Pipher, JL Forrest, WJ McCreight, CR McKelvey, M Hoffmann, WF Eisenhardt, P Surace, JA Reach, W Moseley, SH Arendt, R Stewart, KP Robinson, FD BE Strojnik, M Andresen, BF TI Calibration and performance of the Infrared Array Camera (IRAC) SO INFRARED SPACEBORNE REMOTE SENSING VIII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Infrared Spaceborne Remote Sensing VIII CY JUL 31-AUG 01, 2000 CL SAN DIEGO, CA SP SPIE DE infrared astronomy; infrared arrays; calibration; SIRTF; IRAC AB The Infrared Array Camera (IRAC) is one of three focal plane instruments in the Space Infrared Telescope Facility (SIRTF). IRAC is a four-channel camera that obtains simultaneous images at 3.6, 4.5, 5.8, and 8 microns. Two adjacent 5.12x5.12 arcmin fields of view in the SIRTF focal plane are viewed by the four channels in pairs (3.6 and 5.8 microns; 4.5 and 8 microns). AU four detector arrays in the camera are 256x256 pixels in size, with the two shorter wavelength channels using InSb and the two longer wavelength channels using Si:As IBC detectors. We describe here the results of the instrument functionality and calibration tests completed at Goddard Space flight Center, and provide estimates of the in-flight sensitivity and performance of IRAC in SIRTF. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Hora, JL (reprint author), Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. OI Hora, Joseph/0000-0002-5599-4650; Arendt, Richard/0000-0001-8403-8548; Reach, William/0000-0001-8362-4094 NR 7 TC 16 Z9 16 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3776-X J9 P SOC PHOTO-OPT INS PY 2000 VL 4131 BP 13 EP 25 DI 10.1117/12.406553 PG 13 WC Instruments & Instrumentation; Remote Sensing; Optics SC Instruments & Instrumentation; Remote Sensing; Optics GA BR62C UT WOS:000166963500003 ER PT J AU Polhemus, JT Polhemus, DA AF Polhemus, JT Polhemus, DA TI The Trepobatinae (Gerridae) of New Guinea and surrounding regions, with a review of the World fauna. Part 5. Taxonomic and distributional addenda SO INSECT SYSTEMATICS & EVOLUTION LA English DT Article ID HETEROPTERA AB The small waterstriders of the subfamily Trepobatinae have radiated extensively on New Guinea and surrounding archipelagos. The present contribution is the fifth in a series of reports dealing with this endemic fauna, and presents taxonomic and distributional addenda to our previous tribal level treatments. The following new species are described: Ciliometra setosa from southern Papua New Guinea, Ciliometra waigeo from Waigeo and Batanta Islands, Ciliometra minajerwi from southern Irian Jaya, Stygiobates iweka from southern Irian Jaya, Stygiobates mubi from southern Papua New Guinea, Stygiobates rajana from Waigeo and Gam Islands, Calyptobates kopi from southern Irian Jaya, and Calyptobates kamoro from southern Irian Jaya. The previously unknown male of Iobates somare Polhemus & Polhemus is also described, and new distribution records are provided for the following taxa based on recent collections in northern New Guinea and the Raja Ampat Islands: Iobates affinis (Esaki), Metrobatopsis flavonotatus Esaki, Stygiobates iriana Polhemus & Polhemus, Pseudohalobates inobonto Polhemus & Polhemus, Stenobates australicus Polhemus & Polhemus, Stenobates fakfak Polhemus & Polhemus, Stenobates kamojo Polhemus & Polhemus and Rheumatometroides sele Polhemus & Polhemus. New distribution records are also provided for the following species occurring outside the New Guinea region, based on recent collections in Southeast Asia: Calyptobates samarinda Polhemus & Polhemus from Sumba, and Naboandelus signatus Distant from southern Vietnam. Revised keys are presented for the New Guinea species of Ciliometra, Stygiobates, lobates and Cryptobates, accompanied by updated distribution maps and illustrations of key characters. C1 Univ Colorado Museum, Englewood, CO 80110 USA. Smithsonian Inst, Dept Entomol, MRC 105, Washington, DC 20560 USA. RP Polhemus, JT (reprint author), Univ Colorado Museum, 3115 S YOrk St, Englewood, CO 80110 USA. NR 9 TC 3 Z9 3 U1 1 U2 2 PU APOLLO BOOKS PI STENSTRUP PA KIRKEBY SAND, 19, DK-5771 STENSTRUP, DENMARK SN 0013-8711 J9 INSECT SYST EVOL JI Insect Syst. Evol. PY 2000 VL 31 IS 3 BP 291 EP 316 PG 26 WC Evolutionary Biology; Entomology SC Evolutionary Biology; Entomology GA 392NQ UT WOS:000166417900005 ER PT S AU Golub, L DeLuca, EE Bookbinder, J Cheimets, P Shibasaki, K Sakao, T Kano, R AF Golub, L DeLuca, EE Bookbinder, J Cheimets, P Shibasaki, K Sakao, T Kano, R BE Fineschi, S Korendyke, CM Siegmund, OHW Woodgate, BE TI A high resolution grazing incidence telescope for the Solar-B observatory SO INSTRUMENTATION FOR UV/EUV ASTRONOMY AND SOLAR MISSIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Instrumentation for UV/EUV Astronomy and Solar Missions CY JUL 30-AUG 01, 2000 CL SAN DIEGO, CA SP SPIE ID X-RAY TELESCOPE; MAGNETIC RECONNECTION; ACTIVE-REGION; NUMERICAL SIMULATIONS; CHROMOSPHERIC EVAPORATION; TRANSIENT BRIGHTENINGS; TEMPERATURE STRUCTURE; ENERGETIC PARTICLES; FLARE TEMPERATURES; TRANSITION REGION AB The X-ray observations from the Yohkoh SXT provided the greatest step forward in our understanding of the solar corona in nearly two decades. We believe that the scientific objectives of the Solar-B mission can best be achieved with an X-ray telescope (XRT) similar to the SXT, but with significant improvements in spatial resolution and in temperature response that take into account the knowledge gained from Yohkoh. We present the scientific justification for this view, discuss the instrumental requirements that flow from the scientific objectives, and describe the instrumentation that will meet these requirements. XRT is a grazing-incidence (GI) modified Welter I X-ray telescope, of 35cm inner diameter and 2.7m focal length. The 2048x2048 back-illuminated CCD has 13.5 mu pixels, corresponding to 1.0 arcsec and giving full Sun field of view. This will be the highest resolution GI X-ray telescope ever flown for Solar coronal studies, and it has been designed specifically to observe both the high and low temperature coronal plasma. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Golub, L (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Woodgate, Bruce/D-2970-2012; DeLuca, Edward/L-7534-2013; OI DeLuca, Edward/0000-0001-7416-2895; Golub, Leon/0000-0001-9638-3082 NR 77 TC 9 Z9 9 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3784-0 J9 P SOC PHOTO-OPT INS PY 2000 VL 4139 BP 313 EP 327 DI 10.1117/12.410531 PG 15 WC Engineering, Aerospace; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Spectroscopy SC Engineering; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Spectroscopy GA BR89U UT WOS:000167974600030 ER PT S AU Gardner, LD Atkins, N Fineschi, S Smith, PL Kohl, JL Maccari, L Romoli, M AF Gardner, LD Atkins, N Fineschi, S Smith, PL Kohl, JL Maccari, L Romoli, M BE Fineschi, S Korendyke, CM Siegmund, OHW Woodgate, BE TI Efficiency variations of UVCS/SOHO based on laboratory measurements of replica gratings SO INSTRUMENTATION FOR UV/EUV ASTRONOMY AND SOLAR MISSIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Instrumentation for UV/EUV Astronomy and Solar Missions CY JUL 30-AUG 01, 2000 CL SAN DIEGO, CA SP SPIE DE gratings; efficiency; UVCS/SOHO ID ULTRAVIOLET CORONAGRAPH SPECTROMETER; SOLAR AB We have carried out measurements of efficiency as functions of position across the surfaces of replica gratings made from the same masters as the UVCS/SOHO flight units. Variations in first order efficiency which significantly affect the interpretation of UVCS data are found along the direction perpendicular to the grooves. Variations are also found along the direction parallel to the grooves, but these do not seriously affect UVCS data interpretation. The measurements and their application to the radiometric calibration of UVCS/SOHO are discussed. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Gardner, LD (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Woodgate, Bruce/D-2970-2012; Romoli, Marco/H-6859-2012 NR 4 TC 26 Z9 26 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3784-0 J9 P SOC PHOTO-OPT INS PY 2000 VL 4139 BP 362 EP 369 DI 10.1117/12.410542 PG 8 WC Engineering, Aerospace; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Spectroscopy SC Engineering; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Spectroscopy GA BR89U UT WOS:000167974600034 ER PT S AU Ivan, A Bruni, R Byun, K Gorenstein, P Romaine, S AF Ivan, A Bruni, R Byun, K Gorenstein, P Romaine, S BE Carter, CB Hall, EL Nutt, SR Briant, CL TI Optimization of the broadband reflectance of graded multilayers for hard X-ray mirrors SO INTERFACIAL ENGINEERING FOR OPTIMIZED PROPERTIES II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Interfacial Engineering for Optimized Properties II held at the 1999 MRS Fall Meeting CY DEC 01-02, 1999 CL BOSTON, MA SP Mat Res Soc, GE Res & Dev Ctr, Univ Minnesota, Univ So Calif, Brown Univ, Ctr Adv Mat AB Multilayer structures with depth graded spacing can present a high reflectivity in a broad energy bandpass for hard X-rays (>20 keV) if the interface roughness/diffuseness is controlled and minimized. We present an optimization study of several multilayer systems deposited by DC magnetron sputtering on [111] silicon wafer substrates. The material combinations presented in this work are W/Si, W/C, WSi2/Si, Pt/C, Ni/C, and Mo/Si. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Ivan, A (reprint author), Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-494-7 J9 MATER RES SOC SYMP P PY 2000 VL 586 BP 105 EP 110 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA BR05B UT WOS:000165506300015 ER PT S AU Morel, S Traub, WA Bregman, JD Mah, R Wilson, E AF Morel, S Traub, WA Bregman, JD Mah, R Wilson, E BE Lena, PJ Quirrenbach, A TI Fringe-tracking experiments at the IOTA interferometer SO INTERFEROMETRY IN OPTICAL ASTRONOMY, PTS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Interferometry in Optical Astronomy CY MAR 27-29, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc DE fringe-tracking; coherencing; infrared detectors; precision positioning; prediction ID PHASE AB The first tests of an infrared fringe-tracker prototype for the IOTA interferometer (Mount-Hopkins, Arizona) were carried out during 1999. The aim of this real-time system is to minimize the optical path difference (OPD) fluctuations between the two beams such that interference fringes (obtained in J, K, or L bend) can always be observed within the "scan window" given by the instrument. After an introduction of the employed technology (hardware and software), we present results obtained from star observations. Finally, we discuss the possibility of improving the fringe-tracker by prediction of the OPD, using statistical properties of its fluctuations. The improvement of the fringe-tracker already existing for the FLUOR recombiner is discussed as well. C1 Smithsonian Astrophys Observ, FL Whipple Observ, Amado, AZ 85645 USA. RP Morel, S (reprint author), Smithsonian Astrophys Observ, FL Whipple Observ, 670 Mt Hopkins Rd, Amado, AZ 85645 USA. NR 10 TC 8 Z9 8 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3631-3 J9 P SOC PHOTO-OPT INS PY 2000 VL 4006 BP 506 EP 513 DI 10.1117/12.390247 PN 1&2 PG 8 WC Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BQ70B UT WOS:000089218500056 ER PT S AU Monnier, JD Danchi, WC Hale, DS Tuthill, PG Townes, CH AF Monnier, JD Danchi, WC Hale, DS Tuthill, PG Townes, CH BE Lena, PJ Quirrenbach, A TI Combining high spectral and spatial resolution in the mid-infrared SO INTERFEROMETRY IN OPTICAL ASTRONOMY, PTS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Interferometry in Optical Astronomy CY MAR 27-29, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc DE astrochemistry; interferometry; spectroscopy; infrared; IRC+10216; VYCMa; filterbank; ammonia; silane ID EMISSION AB A novel, fast-switching filterbank system has been incorporated into the Infrared Spatial Interferometer (TSI) to allow high spectral resolution observations of mid-infrared spectral lines, while precisely calibrating atmospheric fluctuations. This system allows the complex visibility in a spectral line to be measured relative to the continuum with high precision, about 1% in visibility amplitude and a few degrees in visibility phase. The high spectral resolving power (R similar to 100000) and spatial resolution (1/10 arcsecond) allow the formation radii of various polyatomic molecules (e.g., ammonia and silane) to be directly measured. Initial results for carbon star IRC +10216 and red supergiant VY CMa are presented. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Monnier, JD (reprint author), Smithsonian Astrophys Observ, MS 42,60 Garden St, Cambridge, MA 02138 USA. OI Monnier, John D/0000-0002-3380-3307 NR 15 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3631-3 J9 P SOC PHOTO-OPT INS PY 2000 VL 4006 BP 574 EP 583 DI 10.1117/12.390255 PN 1&2 PG 10 WC Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BQ70B UT WOS:000089218500064 ER PT S AU Millan-Gabet, R Schloerb, FP Traub, WA AF Millan-Gabet, R Schloerb, FP Traub, WA BE Lena, PJ Quirrenbach, A TI The circumstellar environment of Herbig Ae/Be stars as seen by the IOTA SO INTERFEROMETRY IN OPTICAL ASTRONOMY, PTS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Interferometry in Optical Astronomy CY MAR 27-29, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc DE interferometer; IOTA; Herbig Ae/Be stars; infrared excess; cicumstellar dust; accretion disk; dust envelopes ID INTERMEDIATE-MASS STARS; DISKS; AE; EVOLUTION; ENVELOPES; EMISSION; MATTER; DUST AB We have conducted the first systematic study of Herbig Ae/Be stars using the technique of long baseline stellar interferometry. The Infrared Optical Telescope Array (IOTA) resolves the source of the near-infrared excess flux charateristic of these systems in 11 of the 15 stars observed. A close companion to MWC 361-A (18 mas separation) has been detected interferometrically for the first time. The visibility data has been interpreted within the context of four models which represent the range of plausible representations for the brightness of the excess emission: a Gaussian distribution, a narrow uniform ring, an accretion disk, and an infrared companion. We find that the large sizes measured by the interferometer, 0.5 - 5.9 AU, essentially invalidate accretion disk models that had been previously used to explain the spectroscopic observations. Although a unique model can not be determined for each source due to limited spatial frequency coverage, the observed symmetry of the sources favors, for the ensemble of the data, models in which the circumstellar dust is distributed in spherical envelopes. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Millan-Gabet, R (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 22 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3631-3 J9 P SOC PHOTO-OPT INS PY 2000 VL 4006 BP 605 EP 616 DI 10.1117/12.390260 PN 1&2 PG 12 WC Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BQ70B UT WOS:000089218500068 ER PT S AU Traub, WA Carleton, NP Bregman, JD Brewer, MK Lacasse, MG Maymounkov, P Millan-Gabet, R Monnier, JD Morel, S Papaliolios, C Pearlman, MR Porro, IL Schloerb, FP Souccar, K AF Traub, WA Carleton, NP Bregman, JD Brewer, MK Lacasse, MG Maymounkov, P Millan-Gabet, R Monnier, JD Morel, S Papaliolios, C Pearlman, MR Porro, IL Schloerb, FP Souccar, K BE Lena, PJ Quirrenbach, A TI The third telescope project at the IOTA interferometer SO INTERFEROMETRY IN OPTICAL ASTRONOMY, PTS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Interferometry in Optical Astronomy CY MAR 27-29, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc DE interferometer; IOTA AB The third telescope project to enable phase-closure observations at the IOTA interferometer is well underway, and is anticipated to be completed later this year. For this project, we present the main technical improvements which we have already made or expect to make, including a new VxWorks control system, improved star acquisition cameras, improved siderostat and primary mirror supports, five-axis control of the telescope secondary mirrors, automated control of the long delay line, trihedral retroreflectors, three-beam combination, the PICNIC camera, and fringe packet tracking. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Traub, WA (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 10 TC 18 Z9 18 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3631-3 J9 P SOC PHOTO-OPT INS PY 2000 VL 4006 BP 715 EP 722 DI 10.1117/12.390273 PN 1&2 PG 8 WC Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BQ70B UT WOS:000089218500080 ER PT J AU Clamp, JC Coats, DW AF Clamp, JC Coats, DW TI Planeticovorticella finleyi n.g., n.sp (Peritrichia, Vorticellidae), a planktonic ciliate with a polymorphic life cycle SO INVERTEBRATE BIOLOGY LA English DT Article DE conjugation; Chesapeake Bay ID CILIOPHORA; REVISION AB Free-swimming trophonts of a sessiline peritrich ciliate were discovered in plankton samples from the Rhode River, Maryland, and main-stem Chesapeake Bay. Cultures revealed that the species comprises both free trophonts that swim with their peristomial cilia and sessile trophonts that attach to substrates with a contractile, helically-twisted stalk. Trophonts with a short, rigid stalk or no definite stalk also were seen in culture. Binary fission of free-swimming trophonts usually produced a pair of trophonts attached scopula to scopula by a short, rigid stalk. These persisted for some time as distinctive, spinning doublets before their stalks broke and they separated. Binary fission of free-swimming trophonts also yielded trophont-telotroch pairs that stayed together for only a short time. Telotrochs from these pairs were presumably the source of attached trophonts. Conjugation occurred in both free and attached trophonts. Formation of microconjugants involved at least 2 successive divisions of a trophont. Possession of a helically-twisted, contractile stalk placed the peritrich in the family Vorticellidae, but its unique combination of life-cycle stages marks it as a new genus and species, Planeticovorticella finleyi. The morphology and life cycle of P. finleyi raise questions about the present classification of sessiline peritrichs and suggest that it may be at least partly artificial. Stalkless plank tonic peritrichs that swim with their oral cilia as do trophonts of P. finleyi may have evolved from sessile ancestors by an alteration in the life cycle that created unstable clusters of trophonts on a single parental stalk. Free-swimming trophonts would originate from breakup of these clusters. C1 N Carolina Cent Univ, Dept Biol, Durham, NC 27707 USA. Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. RP Clamp, JC (reprint author), N Carolina Cent Univ, Dept Biol, Durham, NC 27707 USA. NR 33 TC 10 Z9 10 U1 2 U2 3 PU AMER MICROSCOPICAL SOC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 USA SN 1077-8306 J9 INVERTEBR BIOL JI Invertebr. Biol. PY 2000 VL 119 IS 1 BP 1 EP 16 PG 16 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA 292XQ UT WOS:000085821100001 ER PT J AU Pernet, B AF Pernet, B TI Reproduction and development of three symbiotic scaleworms (Polychaeta : Polynoidae) SO INVERTEBRATE BIOLOGY LA English DT Article DE Arctonoe; larval feeding; trochophore larvae ID SPECIALIZATION; CALIFORNIA; MECHANISMS; LARVAE AB The reproduction and development of symbiotic polynoid polychaetes in the genus Arctonoe were examined with light and electron microscopy. Around San Juan Island, Washington, the 3 described Arctonoe spp. have very similar reproductive periods and ontogenies. Free-spawned eggs 80 mu m in diameter fuse with sperm and develop into planktonic, feeding larvae that bear a prototroch, but no metatroch or food groove cilia. Larvae begin feeding only after the development of episphere ciliary bands and an oral brush, consistent with the hypothesis that these structures are involved in particle capture and handling. Metamorphosis occurs in the laboratory in the absence of hosts after 6-12 weeks of feeding and growth. Juveniles begin feeding using the pharyngeal jaws several days after metamorphosis is complete. In the laboratory, worms reach sexual maturity 4-6 months after metamorphosis. The long planktonic larval period of Arctonoe spp. probably leads to high dispersal, suggesting that geographic differentiation in host preferences is unlikely except over large spatial scales. Naive juveniles of Arctonoe spp. can now be obtained from laboratory cultures to test the hypothesis that genetically based host preferences are important in determining host-use patterns in these symbionts. C1 Univ Washington, Dept Zool, Friday Harbor, WA 98250 USA. Univ Washington, Friday Harbor Labs, Friday Harbor, WA 98250 USA. RP Pernet, B (reprint author), Smithsonian Marine Stn Ft Pierce, 701 Seaway Dr, Ft Pierce, FL 34949 USA. NR 56 TC 6 Z9 8 U1 0 U2 3 PU AMER MICROSCOPICAL SOC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 USA SN 1077-8306 J9 INVERTEBR BIOL JI Invertebr. Biol. PY 2000 VL 119 IS 1 BP 45 EP 57 PG 13 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA 292XQ UT WOS:000085821100005 ER PT J AU Pernet, B AF Pernet, B TI A scaleworm's setal snorkel SO INVERTEBRATE BIOLOGY LA English DT Article DE annelid; polychaete; setae; Sigalionidae; Sthenelais ID POLYCHAETA; WORMS AB Setae of the first segment of the marine annelid Sthenelais berkeleyi (family Sigalionidae) are arranged in the shape of an antero-dorsally directed tube. When the worm is in resting position buried in sediment, this setal tube projects slightly from the sediment surface. A current of water is drawn into it by cilia on the parapodia of the first segment. The water is then diverted to a pair of lateral spaces between the body wall and elytra, moved posteriorly in these spaces along the length of the body by segmental cilia, and eventually exits posteriorly or ventrally. This flow permits the worm to respire while remaining buried and immobile for long periods of time, waiting for prey to move over the sediment near it. Setae of the first segment are probably used as snorkels in some other infaunal sigalionids as well. C1 Friday Harbor Labs, Friday Harbor, WA 98250 USA. RP Pernet, B (reprint author), Smithsonian Marine Stn, Ft Pierce, FL 34949 USA. OI Pernet, Bruno/0000-0002-6200-5654 NR 17 TC 6 Z9 6 U1 0 U2 0 PU AMER MICROSCOPICAL SOC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 USA SN 1077-8306 J9 INVERTEBR BIOL JI Invertebr. Biol. PY 2000 VL 119 IS 2 BP 147 EP 151 PG 5 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA 315KG UT WOS:000087112500003 ER PT J AU Daly, JW Garraffo, HM Jain, P Spande, TF Snelling, RR Jaramillo, C Rand, AS AF Daly, JW Garraffo, HM Jain, P Spande, TF Snelling, RR Jaramillo, C Rand, AS TI Arthropod-frog connection: Decahydroquinoline and pyrrolizidine alkaloids common to microsympatric myrmicine ants and dendrobatid frogs SO JOURNAL OF CHEMICAL ECOLOGY LA English DT Article DE alkaloids; coccinellines; decahydroquinolines; indolizidines; pyrrolidines; pyrrolizidines; dendrobatid frogs; myrmicine ants; coccinellid beetles; millipedes ID DIETARY ALKALOIDS; SKIN ALKALOIDS AB Neotropical poison frogs (Dendrobatidae) contain a wide variety of lipophilic alkaloids, apparently accumulated unchanged into skin glands from dietary sources. Panamanian poison frogs (Dendrobates auratus) raised in a large, screened, outdoor cage and provided for six months with leaf-litter from the frog's natural habitat, accumulated a variety of alkaloids into the skin. These included two isomers of the ant pyrrolizidine 251K; two isomers of the 3,5-disubstituted indolizidine 195B; an alkaloid known to occur in myrmicine ants; another such indolizidine, 211E; two pyrrolidines, 197B and 223N, the former known to occur in myrmicine ants; two tricyclics, 193C and 219I, the former known to occur as precoccinelline in coccinellid beetles; and three spiropyrrolizidines, 222, 236, and 252A, representatives of an alkaloid class known to occur in millipedes. The alkaloids 211E, 197B, and 223N appear likely to derive in part from ants that entered the screened cage. In addition, the frog skin extracts contained trace amounts of four alkaloids, 205D, 207H, 219H, and 231H, of unknown structures and source. Wild-caught frogs from the leaf-litter site contained nearly 40 alkaloids, including most of the above alkaloids. Pumiliotoxins and histrionicotoxins were major alkaloids in wild-caught frogs, but were absent in captive-raised frogs. Ants microsympatric with the poison frog at the leaf-litter site and at an island site nearby in the Bay of Panama were examined for alkaloids. The decahydroquinoline (-)-cis-195A and two isomers of the pyrrolizidine 251K were found to be shared by microsympatric myrmicine ants and poison frogs. The proportions of the two isomers of 251K were the same in ant and frog. C1 NIDDKD, Bioorgan Chem Lab, NIH, Bethesda, MD 20892 USA. Los Angeles Cty Museum Nat Hist, Los Angeles, CA 90007 USA. Smithsonian Trop Res Inst, Panama City, Panama. RP Daly, JW (reprint author), NIDDKD, Bioorgan Chem Lab, NIH, Bethesda, MD 20892 USA. NR 16 TC 66 Z9 71 U1 1 U2 3 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0098-0331 EI 1573-1561 J9 J CHEM ECOL JI J. Chem. Ecol. PD JAN PY 2000 VL 26 IS 1 BP 73 EP 85 DI 10.1023/A:1005437427326 PG 13 WC Biochemistry & Molecular Biology; Ecology SC Biochemistry & Molecular Biology; Environmental Sciences & Ecology GA 284LP UT WOS:000085334100005 ER PT J AU Jett, JA AF Jett, JA TI Recent literature on foraminifera SO JOURNAL OF FORAMINIFERAL RESEARCH LA English DT Bibliography C1 Smithsonian Inst, NMNH, Dept Paleobiol, MRC 121, Washington, DC 20560 USA. RP Jett, JA (reprint author), Smithsonian Inst, NMNH, Dept Paleobiol, MRC 121, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU CUSHMAN FOUNDATION FORAMINIFERAL RES PI CAMBRIDGE PA MUSEUM COMPARATIVE ZOOLOGY, DEPT INVERTEBRATE PALEONTOLOGY 26 OXFORD ST, HARVARD UNIV, CAMBRIDGE, MA 02138 USA SN 0096-1191 J9 J FORAMIN RES JI J. Foraminifer. Res. PD JAN PY 2000 VL 30 IS 1 BP 77 EP 78 DI 10.2113/0300077 PG 2 WC Paleontology SC Paleontology GA 281DR UT WOS:000085143300007 ER PT J AU Manheim, MH Listi, GA Barsley, RE Musselman, R Barrow, NE Ubelaker, DH AF Manheim, MH Listi, GA Barsley, RE Musselman, R Barrow, NE Ubelaker, DH TI In vivo facial tissue depth measurements for children and adults SO JOURNAL OF FORENSIC SCIENCES LA English DT Article DE forensic science; facial tissue depth standards; ultrasound; adults and children AB This study reports results of a facial tissue depth measurements project conducted over a two-year period on a modern sample of children and adults of both sexes and varying ages and races. The purpose of this research was to increase available tissue depth data for children and update facial tissue depth measurements for American adults. Most volunteers for this project were patients or visitors to the pediatric clinic at the Louisiana State University Medical Center, School of Dentistry, in New Orleans. Using state-of-the-art ultrasound technology, we scanned 551 children and 256 adults at 19 points across the face. Thirteen of the scanned points were traditional landmarks while six others were areas not measured by previous researchers or were points for which very little data exist for both children and adults. For this presentation, we analyzed data for 515 children and 197 adults. Results of Pearson's correlations, analysis of variance, and paired t-tests indicate that age, sex, and race are significant factors when considering tissue depth means for different measurement locations across the human face. These new standards are compared to the work of other researchers. Our results provide valuable assistance in both two-dimensional and three-dimensional facial reproductions and superimpositions. C1 Louisiana State Univ, Dept Geog & Anthropol, LSU FACES Lab, Baton Rouge, LA 70803 USA. Louisiana State Univ, Med Ctr, Sch Dent, New Orleans, LA 70119 USA. Smithsonian Inst, Natl Museum Nat Hist, Dept Anthropol, Washington, DC 20560 USA. RP Manheim, MH (reprint author), Louisiana State Univ, Dept Geog & Anthropol, LSU FACES Lab, Baton Rouge, LA 70803 USA. NR 28 TC 78 Z9 80 U1 1 U2 7 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 USA SN 0022-1198 J9 J FORENSIC SCI JI J. Forensic Sci. PD JAN PY 2000 VL 45 IS 1 BP 48 EP 60 PG 13 WC Medicine, Legal SC Legal Medicine GA 293BB UT WOS:000085830700009 PM 10641919 ER PT J AU Burckhardt, D Basset, Y AF Burckhardt, D Basset, Y TI The jumping plant-lice (Hemiptera, Psylloidea) associated with Schinus (Anacardiaceae): systematics, biogeography and host plant relationships SO JOURNAL OF NATURAL HISTORY LA English DT Review DE Anacardiaceae; biogeography; cladistics; discriminant analysis; Hemiptera; host plant relationships; phylogeny; Psylloidea; Schinus; taxonomy ID TEMPERATE NEOTROPICAL REGION; ANNOTATED CHECK LIST; HISTORICAL BIOGEOGRAPHY; PARASITE ASSEMBLAGES; PARSIMONY ANALYSIS; ANCESTRAL AREAS; HOMOPTERA; EVOLUTION; PSYLLIDAE; BIOLOGY AB The gall-forming psylloid fauna associated with the temperate Neotropical plant genus Schinus (Anacardiaceae) is revised, and keys are provided for adults, larvae and galls. Fourteen species are recognized in the genus Calophya (Calophyidae), 10 of which are described as new; C. gallifex and C. schini are reinstated from former synonymy with C. rubra. An additional closely related new species, C. clavuligera sp. n., is described from Lithrea spp. In the genus Tainarys (Psyllidae, Rhinocolinae), six species are recognized and, for five of these, Schinus species are confirmed hosts. Two of them are described as new and one is recombined from Leurolophus. A new Leurolophus species is described from Lithrea molleoides. Based on a cladistic analysis Pelmatobrachia, Microceropsylla and Neocalophya are synonymized with Calophya, producing five new and one revised species combinations as well as one nomen nov. A list of the 59 currently recognized species is provided with information on synonymy, distribution and host plants. The cladistic analyses suggest that the Schinus inhabiting calophyids form two monophyletic groups, the C. rubra and C. hermicitae groups, respectively. A discriminant analysis of 15 variables for both males and females provides morphometric characters for separating the morphologically very homogenous adults of the C. rubra group. The phylogenetic relationships of the Rhinocolinae are re-evaluated, and the genera Tainarys and Leurolophus are redefined. Notophyllura is transferred from the Euphyllurinae to the Rhinocolinae. Tainarys forms the sister group of Leurolophus + Notophyllura. Based on mapped distributions four areas of endemism (distribution) are defined: A (Eastern temperate South America), B (Central and Southern Chile, including adjacent parts of Argentina), C (Central Argentina) and D (Peru, Far Northern Chile, and Eastern Bolivia). Cladistic biogeographical analyses with TAS, COMPONENT and an algorithm by Enghoff yielded the general area cladogram (A + (C + (B + D))); the one calculated with BPA differed in the position of D: (D + (A + (B + C))). The reconstruction of vicariant events using a protocol by Hovenkamp, corroborates the former general area cladogram, which is compared to competing hypotheses. The history of dispersal and vicariance events is reconstructed with the programme DIVA. Evidence for cospeciation of Schinus with its associated psylloids is evaluated with COMPONENT and TREE MAP. The likelihood for cospeciation is high in the Calophya hermicitae group, but low in the Calophya rubra group and in Tainarys. The gall shape depends partly from the psylloid, partly from the Schinus phylogeny. C1 Museum Nat Hist, CH-4001 Basel, Switzerland. Smithsonian Trop Res Inst, Balboa, Ancon, Panama. RP Burckhardt, D (reprint author), Museum Nat Hist, Augustinergasse 2, CH-4001 Basel, Switzerland. EM BurckhardtD@ubaclu.unibas.ch; bassety@tivoli.si.edu RI Basset, Yves/B-6642-2014 NR 121 TC 67 Z9 71 U1 3 U2 16 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0022-2933 EI 1464-5262 J9 J NAT HIST JI J. Nat. Hist. PD JAN PY 2000 VL 34 IS 1 BP 57 EP 155 DI 10.1080/002229300299688 PG 99 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 272YK UT WOS:000084678900003 ER PT J AU Posey, KH AF Posey, KH TI The utility of publisher websites SO JOURNAL OF SCHOLARLY PUBLISHING LA English DT Article AB Kevin Posey presents his findings from an informal survey of members of the Association of American University Presses' listserv concerning the purpose and practical value of publisher websites. Posey explores the attitudes towards website utility based on questions that evaluate the website as a sales tool, an adoption tool, and a public relations tool. The responses also address whether the website is maintained on a full- or part- time basis and whether it is a financial burden or too time-consuming. The relationship between publishers' websites and such Internet retailers as Amazon.com is also considered. Posey concludes that, although these websites attract the attention and respect of authors, their potential for generating sales is too limited, given the existence of other online retailers, to give them high priority. C1 Smithsonian Inst Press, Washington, DC USA. RP Posey, KH (reprint author), Smithsonian Inst Press, Washington, DC USA. NR 0 TC 0 Z9 0 U1 1 U2 2 PU UNIV TORONTO PRESS INC PI TORONTO PA JOURNALS DIVISION, 5201 DUFFERIN ST, DOWNSVIEW, TORONTO, ON M3H 5T8, CANADA SN 1198-9742 J9 J SCHOLARLY PUBL JI J. Sch. Publ. PD JAN PY 2000 VL 31 IS 2 BP 77 EP 86 PG 10 WC Humanities, Multidisciplinary; Information Science & Library Science SC Arts & Humanities - Other Topics; Information Science & Library Science GA 283QZ UT WOS:000085287600003 ER PT J AU Reid, RP MacIntyre, IG AF Reid, RP MacIntyre, IG TI Microboring versus recrystallization: Further insight into the micritization process SO JOURNAL OF SEDIMENTARY RESEARCH LA English DT Article ID GRAINS AB SEM observations of lightly etched thin sections of Bahamian sediments reveal an unusual process of micritization that involves carbonate precipitation in microborings concurrent with endolithic activity. A coccoid cyanobacterium, tentatively identified as Solentia sp., bores tunnels, which initially penetrate just beneath grain surfaces and eventually extend throughout the entire grain. These tunnels are filled by radial fibrous aragonite, which is precipitated as the microorganism advances. Extensive multicyclic repetitions of this process result in obliteration of original grain textures with almost complete preservation of grain margins and rare empty bore holes. The rapidly filled tunnels cannot be detected by resin cast embedding techniques that are commonly used to study microboring, This type of multicyclic boring and concurrent filling of bore holes forms micritized grains that can be difficult or impossible to distinguish from micritized grains formed by recrystallization. C1 Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Miami, FL 33149 USA. Natl Museum Nat Hist, Dept Paleobiol, Smithsonian Inst, Washington, DC 20560 USA. RP Reid, RP (reprint author), Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, 4600 Rickenbacker Causeway, Miami, FL 33149 USA. NR 17 TC 56 Z9 66 U1 0 U2 7 PU SEPM-SOC SEDIMENTARY GEOLOGY PI TULSA PA 1731 E 71ST STREET, TULSA, OK 74136-5108 USA SN 1073-130X J9 J SEDIMENT RES JI J. Sediment. Res. PD JAN PY 2000 VL 70 IS 1 BP 24 EP 28 DI 10.1306/2DC408FA-0E47-11D7-8643000102C1865D PN A PG 5 WC Geology SC Geology GA 287NX UT WOS:000085513100003 ER PT J AU Sadler, PM Coyle, HP Schwartz, M AF Sadler, PM Coyle, HP Schwartz, M TI Engineering competitions in the middle school classroom: Key elements in developing effective design challenges SO JOURNAL OF THE LEARNING SCIENCES LA English DT Article AB Engineering challenges that involve both the design and building of devices that satisfy constraints are increasingly employed in precollege science courses. We have experimented with exercises that are distinguished from those employed with elite students by reducing competition and increasing cooperation through the use of tests against nature, large dynamic ranges in performance, initial prototype designs, and alternative methods of recording and presenting results. We find that formulating easily understood goals helps engage students in fascinatingly creative processes that expose the need for a scientific methodology. Such challenges engage male and female students equally, helping to erase the gender disparity in familiarity with the technology and skills common to physical science. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Harvard Univ, Grad Sch Educ, Cambridge, MA 02138 USA. RP Sadler, PM (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS-71, Cambridge, MA 02138 USA. EM philip_sadler@harvard.edu NR 33 TC 47 Z9 47 U1 0 U2 7 PU ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXFORDSHIRE, ENGLAND SN 1050-8406 J9 J LEARN SCI JI J. Learn. Sci. PY 2000 VL 9 IS 3 BP 299 EP 327 DI 10.1207/S15327809JLS0903_3 PG 29 WC Education & Educational Research; Psychology, Educational SC Education & Educational Research; Psychology GA 329KP UT WOS:000087906400003 ER PT J AU Luhr, JF AF Luhr, JF TI The geology and petrology of Volcan San Juan (Nayarit, Mexico) and the compositionally zoned Tepic Pumice SO JOURNAL OF VOLCANOLOGY AND GEOTHERMAL RESEARCH LA English DT Review DE Volcan San Juan; geology; petrology; Plinian ID SIERRA-LA-PRIMAVERA; MOUNT ST-HELENS; LOWER CRUSTAL XENOLITHS; FALLOUT TEPHRA VOLUMES; CALC-ALKALINE MAGMAS; EAST PACIFIC RISE; WESTERN MEXICO; RIVERA PLATE; JALISCO BLOCK; CRATER LAKE AB Volcan San Juan is the westernmost Quaternary composite volcano in the Mexican Volcanic Belt. Its activity is divided into three stages of decreasing eruptive volume. During stage-1 activity, the main cone of San Juan and the adjacent Cerro Alto grew to a combined volume of similar to 60 km(3) through eruption of hornblende-bearing andesites, dacites, and rhyodacites. Stage 1 included explosive eruptions of hornblende-dacite and an andesite dated at 33,750 a (years ago) and 23,010 a. Stage-2 activity involved a major Plinian eruption 14,770 a that produced the hypersthene-hornblende-bearing, compositionally zoned, rhyodacitic-andesitic Tepic Pumice and led to formation of an oval-shaped caldera 4 x 1 km in diameter. Tepic, the capital city of Nayarit State, with a population of similar to 250,000, lies at the NE foot of Volcan San Juan. This location was buried under 2-9 m of rhyodacitic pumice-fall deposits from the Tepic Pumice eruption. Erosion has since removed virtually all exposures of Tepic Pumice > 15 km from the caldera. The estimated volume of erupted tephra is 5.6 km(3), equivalent to 1.2 km(3) of magma. modeling of the eruption dynamics indicates that as the eruption evolved the column height increased from similar to 15 km to similar to 24 km and maximum mass discharge rate increased from similar to 3 x 10(6) kg/s to similar to 6 x 10(7) kg/s. During stage-3 activity, a hornblende-andesitic lava dome partially filled the caldera and sent block lava flows down the north slope of thr cone; total erupted volume was similar to 0.55 km(3). Compared to other composite volcanoes of the western Mexican Volcanic Belt, the products from San Juan have the highest Sr contents and the lowest Rb, Y, Yb, and Lu contents, resulting in high La/Yb and Sr/Y, with low: Rb/Sr. These observations indicate a strong slab-melt component at San Juan, consistent with its proximity to thr Middle America Trench where young, hot lithosphere is subducting The San Juan andesites, dacites, and rhyodacites also have relatively high Sr-87/Sr-86, Pb-206/Pb-204, Pb-207/Pb-204, and Pb-208/Pb-204, and low epsilon(Nd) values compared to these other volcanoes, which appear to reflect significant crustal contamination of San Juan's magmas. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Smithsonian Inst, Dept Mineral Sci, Washington, DC 20560 USA. RP Luhr, JF (reprint author), Smithsonian Inst, Dept Mineral Sci, NHB 119, Washington, DC 20560 USA. NR 132 TC 41 Z9 41 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-0273 J9 J VOLCANOL GEOTH RES JI J. Volcanol. Geotherm. Res. PD JAN PY 2000 VL 95 IS 1-4 BP 109 EP 156 DI 10.1016/S0377-0273(99)00133-X PG 48 WC Geosciences, Multidisciplinary SC Geology GA 297EN UT WOS:000086069100008 ER PT J AU Richman, LK Montali, RJ Cambre, RC Schmitt, D Hardy, D Hildbrandt, T Bengis, RG Hamzeh, FM Shahkolahi, A Hayward, GS AF Richman, LK Montali, RJ Cambre, RC Schmitt, D Hardy, D Hildbrandt, T Bengis, RG Hamzeh, FM Shahkolahi, A Hayward, GS TI Clinical and pathological findings of a newly recognized disease of elephants caused by endotheliotropic herpesviruses SO JOURNAL OF WILDLIFE DISEASES LA English DT Article DE elephant; Elephas maximus; endotheliotropic viruses; famciclovir; herpesvirus; Loxodonta africana; new disease; penciclovir ID INFECTION; FAMCICLOVIR; BRL-39123; MAXIMUS AB The unique clinical and pathological findings in nine Asian (Elephas maximus) and two African (Loxodonta africana) elephants from North American Zoos with a highly fatal disease caused by novel endotheliotropic herpesviruses are described. Identification of the viruses by molecular techniques and some epidemiological aspects of the disease were previously reported. Consensus primer polymerase chain reaction (PCR) combined with sequencing yielded molecular evidence that confirmed the presence of two novel but related herpesviruses associated with the disease, one in Asian elephants and the second in African elephants. Disease onset was acute, with lethargy, edema of the head and thoracic limbs, oral ulceration and cyanosis of the tongue followed by death of most animals in 1 to 7 days. Pertinent laboratory findings in two of three clinically evaluated animals included lymphocytopenia and thrombocytopenia. Two affected young Asian elephants recovered after a 3 to 4 wk course of therapy with the anti-herpesvirus drug famciclovir. Necropsy findings in the fatal cases included pericardial effusion and extensive petechial hemorrhages in the heart and throughout the peritoneal cavity, hepatomegaly, cyanosis of orrhages and edema throughout the myocardium and mild there were extensive microhemorrages hemorrhagic lesions with inflammation were evident in the tongue, liver, and large intestine. Lesions in these target organs were accompanied by amphophilic to basophilic intranuclear viral inclusion bodies in capillary endothelial cells. Transmission electron microscopy of the endothelial inclusion bodies revealed 80 to 92 nm diameter viral capsids consistent with herpesvirus morphology. The short course of the herpesvirus infections, with sudden deaths in all but the two surviving elephants, was ascribed to acute cardiac failure attributed to herpesvirus-induced capillary injury with extensive myocardial hemorrhage and edema. C1 Smithsonian Inst, Washington, DC 20008 USA. SW Missouri State Univ, Springfield, MO 65804 USA. Dickerson Pk Zoo, Springfield, MO 65803 USA. Inst Zoo Biol & Wildlife Res, Berlin, Germany. Kruger Natl Pk, ZA-1350 Skukuza, South Africa. Johns Hopkins Univ, Sch Med, Baltimore, MD 21205 USA. RP Richman, LK (reprint author), Smithsonian Inst, Natl Zool Pk, Washington, DC 20008 USA. FU NIAID NIH HHS [1 K08 AI01526-01] NR 15 TC 42 Z9 43 U1 3 U2 12 PU WILDLIFE DISEASE ASSN, INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 USA SN 0090-3558 J9 J WILDLIFE DIS JI J. Wildl. Dis. PD JAN PY 2000 VL 36 IS 1 BP 1 EP 12 PG 12 WC Veterinary Sciences SC Veterinary Sciences GA 279WB UT WOS:000085067100001 PM 10682740 ER PT J AU Burke, VJ AF Burke, VJ TI Landscape ecology and species conservation SO LANDSCAPE ECOLOGY LA English DT Article ID HALFWAY C1 Univ Missouri, Sch Nat Sci, Columbia, MO 65211 USA. RP Burke, VJ (reprint author), Smithsonian Inst Press, 470 Lenfant Plaza,Suite 7100, Washington, DC 20560 USA. NR 14 TC 27 Z9 30 U1 2 U2 9 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0921-2973 J9 LANDSCAPE ECOL JI Landsc. Ecol. PD JAN PY 2000 VL 15 IS 1 BP 1 EP 3 DI 10.1023/A:1008156303757 PG 3 WC Ecology; Geography, Physical; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Physical Geography; Geology GA 258GN UT WOS:000083830400001 ER PT B AU Karovska, M Zaccheo, S AF Karovska, M Zaccheo, S BE Livingston, WC Ozguc, A TI Estimating the characteristic size of coronal fine structure SO LAST TOTAL SOLAR ECLIPSE OF THE MILLENNIUM IN TURKEY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on the Last Total Solar Eclipse of the Millennium in Turkey CY AUG 13-15, 1999 CL ISTANBUL, TURKEY SP Turkish Prime Minist, Promot Fund, Sci & Tech Res Council Turkey, Bogazici Univ Res Fund, Magister Tours Inc AB Images of the solar corona obtained during solar eclipses contain many complex components with different spatial scales and a wide range of contrast levels. Spatial characterization of these components is extremely important for understanding the characteristics of the small-scale structure in the corona. We describe here the results from applying two image processing techniques to solar images from the 1991 eclipse taken by S. Koutchmy to study the fine coronal structures. The data analysis indicate quasi-periodicity of the spacings between the small-structures within the streamers and the loop-like structures. Most of the streamer elements are spaced approximately 15 arcseconds apart, and there is possibly a second fundamental period of 9 arcseconds. The analysis also suggest that the elements within the loop-like structures are separated by approximately 14 arcseconds. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Karovska, M (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-032-3 J9 ASTR SOC P PY 2000 VL 205 BP 173 EP 177 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ80P UT WOS:000089620900022 ER PT J AU Rand, H AF Rand, H TI Nicolas de Stael: Catalogue raisonne of his paintings SO LEONARDO LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Rand, H (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU M I T PRESS PI CAMBRIDGE PA FIVE CAMBRIDGE CENTER, CAMBRIDGE, MA 02142 USA SN 0024-094X J9 LEONARDO JI Leonardo PY 2000 VL 33 IS 1 BP 55 EP 58 DI 10.1162/002409400552243 PG 4 WC Art SC Art GA 312YT UT WOS:000086972100011 ER PT J AU Kalfatovic, MR AF Kalfatovic, MR TI Fairfield Porter: A life in art. SO LIBRARY JOURNAL LA English DT Book Review C1 Smithsonian Inst Lib, Washington, DC USA. RP Kalfatovic, MR (reprint author), Smithsonian Inst Lib, Washington, DC USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU BOWKER MAGAZINE GROUP CAHNERS MAGAZINE DIVISION PI NEW YORK PA 249 W 17TH ST, NEW YORK, NY 10011 USA SN 0363-0277 J9 LIBR J JI Libr. J. PD JAN PY 2000 VL 125 IS 1 BP 99 EP 99 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 275DT UT WOS:000084804700097 ER PT S AU Pallavicini, R Randich, S Stauffer, JR Balachandran, SC AF Pallavicini, R Randich, S Stauffer, JR Balachandran, SC BE DaSilva, L Spite, M DeMedeiros, JR TI Lithium in young open clusters SO LIGHT ELEMENTS AND THEIR EVOLUTION SE IAU SYMPOSIA LA English DT Article; Proceedings Paper CT 198th Symposium of the International-Astronomical-Union CY NOV 21-27, 1999 CL NATAL, BRAZIL SP Int Astronim Union ID STARS; ABUNDANCES AB We present lithium abundances for similar to50 late-type members of the similar to30-50 Myr old open clusters IC 2602 and IC 2391 derived from high-resolution spectra obtained at ESO and CTIO. These data enlarge and extend to cooler temperatures previous Li surveys of these clusters by Stauffer et al. (1989) and Randich et al. (1997). We discuss the lithium vs. temperature distribution in the two clusters and we compare our results with those obtained for the Pleiades (similar to120 Myr). The results are discussed in the general framework of lithium depletion in young clusters, from the pre-main sequence to the age of the Pleiades. C1 Osserv Astron Palermo, Palermo, Italy. Osserv Astrofis Arcetri, I-50125 Florence, Italy. Smithsonian Astrophys Observ, Cambridge, MA USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. RP Pallavicini, R (reprint author), Osserv Astron Palermo, Palermo, Italy. NR 11 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 0074-1809 BN 1-58381-048-X J9 IAU SYMP PY 2000 IS 198 BP 350 EP 353 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BU35S UT WOS:000175748500048 ER PT J AU Bunch, TD Wang, S Valdez, R Hoffmann, RS Zhang, Y Liu, A Lin, S AF Bunch, TD Wang, S Valdez, R Hoffmann, RS Zhang, Y Liu, A Lin, S TI Cytogenetics, morphology and evolution of four subspecies of the Giant Sheep argali (Ovis ammon) of Asia SO MAMMALIA LA English DT Article DE argali; evolution; karyotype; morphology; wild sheep ID CHROMOSOMAL EVOLUTION; BAND PATTERNS; KARYOTYPE AB Dalai-lamae (Ovis ammon dalai-lamae), Gobi (O. a. darwini), Kara Tau (O. a. nigrimontana) and Tibetan (O. a. hodgsoni) argali share a 2n = 56 diploid chromosome number and a karyotype consisting of 2 pairs of biarmed and 25 pairs of acrocentric autosomes, a large acrocentric X and a minute Y chromosome. The Giemsa-banding patterns of the largest pair of biarmed chromosomes were identical to those of the largest biarmed chromosomes in all wild sheep and domestic sheep of the genus Ovis. The banding patterns of the second pair of biarmed chromosomes (metacentric) were identical to the third pair of biarmed chromosomes in Ovis with 2n = 54 and to the third largest pair of chromosomes in the 2n = 52 karyotype of Siberian snow sheep (O. nivicola). The G-banded karyotypes of dalai-lamae, darwini, hodgsoni and nigrimontana are consistent with all subspecies of argali (O. ammon), except that the Y chromosome is acrocentric instead of metacentric as typical of the argaliform wild sheep and Ovis. The Dalai-lamae and Tibetan argali specimens exhibit the light-colored, long-haired ruffs and body coloration typical of argalis from the Tibetan Plateau. The Gobi argali, from the extreme western Gobi, is similar to the dark phase argali. C1 Utah State Univ, Dept Anim Dairy & Vet Sci, Logan, UT 84322 USA. New Mexico State Univ, Las Cruces, NM 88003 USA. Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. Chinese Acad Sci, Kunming Inst Zool, Kunmin, Yunnan, Peoples R China. RP Bunch, TD (reprint author), Utah State Univ, Dept Anim Dairy & Vet Sci, Logan, UT 84322 USA. NR 23 TC 6 Z9 10 U1 2 U2 3 PU MUSEUM NAT HIST NATURELLE PI PARIS PA SERVICE PUBLICATIONS SCIENTIFIQUES, 57 RUE CUVIER, 75005 PARIS, FRANCE SN 0025-1461 J9 MAMMALIA JI Mammalia PY 2000 VL 64 IS 2 BP 199 EP 207 DI 10.1515/mamm.2000.64.2.199 PG 9 WC Zoology SC Zoology GA 354VJ UT WOS:000089350100007 ER PT B AU Huchra, JP Mader, J Schneider, SE Skrutskie, MF Jarrett, TH Chester, T Cutri, R AF Huchra, JP Mader, J Schneider, SE Skrutskie, MF Jarrett, TH Chester, T Cutri, R BE KraanKorteweg, RC Henning, PA Andernach, H TI Near IR surveys and the nearby universe SO MAPPING THE HIDDEN UNIVERSE: THE UNIVERSE BEHIND THE MILKY WAY - THE UNIVERSE IN HI, PROCEEDINGS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT International Meeting on Mapping the Hidden Universe CY FEB 23-29, 2000 CL UNIV GUANAJUATO, DEPT ASTRON, GUANAJUATO, MEXICO SP Ctr Latinoamer Fis Mexico, Consejo Estat Ciencia Technol Estado Guanajuato, Secretaria Turismo Estado Guanajuato, UNESCO HO UNIV GUANAJUATO, DEPT ASTRON ID REDSHIFT AB Two new surveys are now underway and nearly completed whose goals are to map the sky at near-infrared wavelengths to study a variety of subjects, from the structure of the Milky Way to the large-scale structure of the Universe. These surveys are DENIS, primarily in the southern hemisphere, and 2MASS, which is covering both hemispheres. The map of nearby large-scale structure as traced by galaxies is one of the primary goals of both surveys. Combined with redshifts and, eventually, velocity independent distances from IR Tully-Fisher, from D-n - sigma studies and from SN Ia light curves, the 2-D maps produced by these surveys will be used to map the 3-D distribution of both galaxies and matter, including dark matter. This should not only precisely determine Omega (M), the mass density in both baryons and dark matter, but also provide exquisite information on the properties of galaxies and biased galaxy formation. The 2MASS redshift survey already has redshifts for 24,000 galaxies brighter than 12.2 and 40,000 galaxies brighter than 13.5 at K-band. With these data we can already provide estimates of the field K-band luminosity function and a wealth of information on the photometric properties of galaxies in the IR. The IR colors of galaxies have a surprisingly small range, which strengthens the justification of near-IR surveys for mapping the nearby Universe. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Huchra, JP (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 11 TC 2 Z9 2 U1 0 U2 1 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-050-1 J9 ASTR SOC P PY 2000 VL 218 BP 101 EP 109 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BR93Z UT WOS:000168122000013 ER PT J AU Dolan, JR Gallegos, CL Moigis, A AF Dolan, JR Gallegos, CL Moigis, A TI Dilution effects on microzooplankton in dilution grazing experiments SO MARINE ECOLOGY PROGRESS SERIES LA English DT Article DE ciliate; oligotrich; tintinnid; phytoplankton; nanoplankton; rotifer; flagellate ID RHODE RIVER ESTUARY; SUB-ARCTIC PACIFIC; GULF-OF-MEXICO; PHYTOPLANKTON GROWTH; SOUTHERN-OCEAN; ARABIAN-SEA; SUBTROPICAL CONVERGENCE; PROTOZOOPLANKTON COMMUNITY; PLANKTON COMMUNITIES; SEASONAL-VARIATIONS AB In dilution experiments, filtered seawater is used to create a gradient of grazing pressure on phytoplankton. Microzooplankton grazing is estimated by examining phytoplankton growth within the gradient. However, the dilution series also represents a resource gradient for microzooplankton. Here we report the effects of dilution on grazers. In 2 standard dilution experiments, using communities from the eutrophic (chlorophyll a = 12 to 15 mu g l(-1)) Rhode River Estuary, we examined the effects of dilution on different groups of microzooplankters: rotifers, tintinnid ciliates, oligotrich ciliates, predacious ciliates, and Mesodinium rubrum. Apparent growth rates of tintinnids and oligotrichs varied with prey concentration, decreasing with the dilution factor from about +0.5 d(-1) in undiluted whole water to about -1 d(-1) in the 5% whole water, closely resembling numerical response curves. Among tintinnids, there was an increase in the relative abundance of larger tintinnids in the time 24 h samples of dilute treatments compared to the less dilute treatments. No consistent dilution effect was shown by rotifers or predacious ciliates. The growth rates of the photosynthetic ciliate M. rubrum increased with dilution, resembling the typical pattern of chlorophyll a and autotrophic nanoplankton. Grazer growth in undiluted waters and grazer mortality in dilute water may be common and result in uncertainty in measured grazing rates. We urge that grazers be examined in grazing experiments not only to assess possible artifacts in grazing rate estimates, but also to provide information, beyond a simple grazing rate, on the grazer populations. C1 Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. Univ Paris 06, CNRS ESA 7076, Marine Microbial Ecol Grp, Stn Zool, F-06230 Villefranche Sur Mer, France. RP Dolan, JR (reprint author), Smithsonian Environm Res Ctr, POB 28, Edgewater, MD 21037 USA. EM dolan@obs-vlfr.fr RI Dolan, John/A-4513-2009; OI Dolan, John/0000-0002-9454-1355; Gallegos, Charles/0000-0001-5112-0166 NR 82 TC 94 Z9 96 U1 1 U2 14 PU INTER-RESEARCH PI OLDENDORF LUHE PA NORDBUNTE 23, D-21385 OLDENDORF LUHE, GERMANY SN 0171-8630 J9 MAR ECOL PROG SER JI Mar. Ecol.-Prog. Ser. PY 2000 VL 200 BP 127 EP 139 DI 10.3354/meps200127 PG 13 WC Ecology; Marine & Freshwater Biology; Oceanography SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Oceanography GA 342NM UT WOS:000088651400011 ER PT J AU Steves, BP Cowen, RK AF Steves, BP Cowen, RK TI Settlement, growth, and movement of silver hake Merluccius bilinearis in nursery habitat on the New York Bight continental shelf SO MARINE ECOLOGY PROGRESS SERIES LA English DT Article DE habitat; juvenile; nursery; growth; distribution; otolith; Merluccius bilinearis ID EARLY-LIFE-HISTORY; OTOLITH MICROSTRUCTURE; MICROSTOMUS-PACIFICUS; DOVER SOLE; LARVAL; RECRUITMENT; VARIABILITY; INCREMENTS; FISHES; AGE AB Silver hake Merluccius bilinearis from the New York Eight were examined for the quality and quantity of their offshore settlement and nursery habitats. Juveniles were collected during 10 cruises between June 1996 and July 1997 using a 2 m beam trawl. Settlement began in July 1996 and peaked in September and October 1996 on the outer shelf (47 to 95 m; 8 to 10 degrees C). Otolith analysis of fish collected during peak settlement was used to calculate the mean age and length at settlement, 34.5 d and 15 mm, and pre- and post-settlement growth rates, 0.35 and 0.51 mm d(-1), respectively. Back calculated settlement dates suggest that peak settlement is tied to the lunar cycle. Post-settlement growth rates along a temperature gradient (8 to 12 degrees C) indicate that silver hake in areas of cooler bottom temperatures (similar to 9 degrees C) were not only larger and more abundant, but also faster growing. Movements of early juveniles imply that settlement habitat is more specific than juvenile nursery habitat. Overall, the outer portion (60 to 95 m) of the continental shelf serves as important nursery habitat for silver hake. C1 SUNY Stony Brook, Marine Sci Res Ctr, Stony Brook, NY 11794 USA. Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Div Marine Biol & Fisheries, Miami, FL 33149 USA. RP Steves, BP (reprint author), SUNY Stony Brook, Marine Sci Res Ctr, Stony Brook, NY 11794 USA. EM steves@serc.si.edu NR 33 TC 22 Z9 22 U1 0 U2 3 PU INTER-RESEARCH PI OLDENDORF LUHE PA NORDBUNTE 23, D-21385 OLDENDORF LUHE, GERMANY SN 0171-8630 J9 MAR ECOL PROG SER JI Mar. Ecol.-Prog. Ser. PY 2000 VL 196 BP 279 EP 290 DI 10.3354/meps196279 PG 12 WC Ecology; Marine & Freshwater Biology; Oceanography SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Oceanography GA 314EG UT WOS:000087041900023 ER PT J AU Marvin, UB AF Marvin, UB TI The Meteoritical Society and Meteoritics and Planetary Science: Past and future SO METEORITICS & PLANETARY SCIENCE LA English DT Editorial Material C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Marvin, UB (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JAN PY 2000 VL 35 IS 1 BP 4 EP 4 PG 1 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 281KY UT WOS:000085160100002 ER PT J AU Guan, YB Crozaz, G AF Guan, YB Crozaz, G TI Light rare earth element enrichments in ureilites: A detailed ion microprobe study SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID ND ISOTOPIC SYSTEMATICS; U-TH-PB; SM-ND; TERRESTRIAL CONTAMINATION; GOALPARA UREILITE; ANTARCTIC UREILITES; ORIGIN; RESOLUTION; METEORITES; PETROGENESIS AB This paper explores the possible origin of the light rare earth element (LREE) enrichments observed in some ureilites, a question that has both petrogenetic and chronologic implications for this group of achondritic meteorites. Rare earth element and other selected elemental abundances were measured in situ in 14 thin sections representing 11 different ureilites. The spatial microdistributions of REEs in C-rich matrix areas of the three ureilites with the most striking V-shaped whole-rock REE patterns (Kenna, Goalpara, and Novo Urei) were investigated using the ion imaging capability of the ion microprobe. All olivines and clinopyroxenes measured have LREE-depleted patterns with little variation in REE abundances, despite large differences in their major element compositions from ureilite to ureilite. Furthermore, we searched for but did not find any minor mineral phases that carry LREEs. The only exception is one Ti-rich area (similar to 20 mu m) in Lewis Cliff (LEW) 85400 with a major element composition similar to that of titanite; REE abundances in this area are high, ranging from La approximate to 400 x CI to Lu approximate to 40 x CI. In contrast, all ion microprobe analyses of C-rich matrix in Kenna, Goalpara, and Novo Urei revealed large LREE enrichments. In addition, C-rich matrix areas in the three polymict ureilites, Elephant Moraine (EET) 83309, EET 87720, and North Haig, which have less pronounced V-shaped whole-rock REE patterns, show smaller but distinct LREE-enrichments. The C-rich matrix in Antarctic ureilites tends to have much lower LREE concentrations than the matrix in non-Antarctic ureilites. There is no obvious association of the LREEs with other major or minor elements in the C-rich areas. Ion images further show that the LREE enrichments are homogeneously distributed on a microscale in most C-rich matrix areas of Kenna, Goalpara, and Novo Urei. These observations suggest that the LREEs in ureilites most probably are absorbed on the surface of fine-grained amorphous graphite in the C-rich matrix. It is unlikely that the LREE enrichments are due to shock melts or are the products of metasomatism on the ureilite parent body. We favor LREE introduction by terrestrial contamination. C1 Washington Univ, McDonnell Ctr Space Sci, St Louis, MO 63130 USA. Washington Univ, Dept Earth & Planetary Sci, St Louis, MO 63130 USA. RP Guan, YB (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Dept Mineral Sci, Washington, DC 20560 USA. EM guany@volcano.si.edu NR 62 TC 14 Z9 15 U1 1 U2 4 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 1086-9379 EI 1945-5100 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JAN PY 2000 VL 35 IS 1 BP 131 EP 144 PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 281KY UT WOS:000085160100017 ER PT B AU Marsden, BG Williams, GV Aksnes, K AF Marsden, BG Williams, GV Aksnes, K BE Fitzsimmons, A Jewitt, D West, RM TI The distant satellites of Uranus and the other giant planets SO MINOR BODIES IN THE OUTER SOLAR SYSTEM SE ESO ASTROPHYSICS SYMPOSIA LA English DT Proceedings Paper CT European-Southern-Observatory Workshop on Minor Bodies of the Outer Solar System (ESO MBOSS-98) CY NOV 02-05, 1998 CL EUROPEAN SO OBSERV, GARCHING, GERMANY SP European SO Observ HO EUROPEAN SO OBSERV AB The steady improvement in our knowledge of the orbits of the two new Uranian satellites is described, including the roles of the 1984 prediscovery images and the 1998 recovery observations. The recognition of distant satellites of the other giant planets, notably the lost possible jovian satellite of 1975, is also discussed. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Marsden, BG (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 15 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-41152-6 J9 ESO ASTROPHY SYMP PY 2000 BP 187 EP 192 DI 10.1007/10651968_28 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BR67P UT WOS:000167129300028 ER PT B AU Dalgarno, A AF Dalgarno, A BE Combes, F DesForets, GP TI Astrophysical importance of H-2 SO MOLECULAR HYDROGEN IN SPACE SE CAMBRIDGE CONTEMPORARY ASTROPHYSICS LA English DT Proceedings Paper CT International Conference on H(2) in Space CY SEP 28-OCT 01, 1999 CL PARIS, FRANCE SP PCMI-CNRS, Collaborat Computat Project 7, Observ Paris, Minist Affaires Etrangeres, Univ Cergy Pontoise, Univ Paris XI, Inst Astrophys Paris ID MOLECULAR-HYDROGEN EMISSION; HUBBLE-SPACE-TELESCOPE; DIFFUSE INTERSTELLAR-MEDIUM; INFRARED RESPONSE; ULTRAVIOLET-RADIATION; SWS SPECTROSCOPY; LINE EMISSION; DENSE CLOUDS; VIBRATIONAL FLUORESCENCE; TRANSITION-PROBABILITIES AB A brief history of observations of H-2 and HD molecules is presented. The properties of H-2 and HD that make observations of them a uniquely powerful diagnostic probe are pointed out. The interpretations of the observations in the ultraviolet, near infrared and infrared made of a diverse range of astrophysical objects are discussed and the influence of H-2 and HD on their evolution is described. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM adalgarno@cfa.harvard.edu NR 103 TC 3 Z9 3 U1 0 U2 2 PU CAMBRIDGE UNIV PRESS PI CAMBRIDGE PA THE PITT BUILDING, TRUMPINGTON ST, CAMBRIDGE CB2 1RP, CAMBS, ENGLAND BN 0-521-78224-4 J9 CAM CONTEMP ASTROPHY PY 2000 BP 3 EP 11 DI 10.1017/CBO9780511564635.004 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BT46Z UT WOS:000173071700001 ER PT B AU van den Ancker, ME Wesselius, PR Tielens, AGGM AF van den Ancker, ME Wesselius, PR Tielens, AGGM BE Combes, F DesForets, GP TI ISO spectroscopy of H-2 in star forming regions SO MOLECULAR HYDROGEN IN SPACE SE CAMBRIDGE CONTEMPORARY ASTROPHYSICS LA English DT Proceedings Paper CT International Conference on H(2) in Space CY SEP 28-OCT 01, 1999 CL PARIS, FRANCE SP PCMI-CNRS, Collaborat Computat Project 7, Observ Paris, Minist Affaires Etrangeres, Univ Cergy Pontoise, Univ Paris XI, Inst Astrophys Paris ID EMISSION AB We have studied molecular hydrogen emission in a sample of 21 YSOs using spectra obtained with the Infrared Space Observatory (ISO). H-2 emission was detected in 12 sources and can be explained as arising in either a shock, caused by the interaction of an outflow from an embedded YSO with the surrounding molecular cloud, or in a PDR surrounding an exposed young early-type star. The distinction between these two mechanisms can not always be made from the pure rotational H2 lines alone. Other tracers, such as PAH emission or [S 1] 25.25 mum emission, are needed to identify the H2 heating mechanism. No deviations from a 3:1 ortho/para ratio of H2 were found. Both shocks and PDRs show a warm and a hot component in H2, which we explain as thermal emission from warm molecular gas (warm component), or UV-pumped infrared fluorescence in the case of PDRs and the re-formation of H2 for shocks (hot component). C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM mario@astro.uva.nl; paul@sron.rug.nl NR 3 TC 0 Z9 0 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI CAMBRIDGE PA THE PITT BUILDING, TRUMPINGTON ST, CAMBRIDGE CB2 1RP, CAMBS, ENGLAND BN 0-521-78224-4 J9 CAM CONTEMP ASTROPHY PY 2000 BP 139 EP 142 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BT46Z UT WOS:000173071700017 ER PT B AU Abel, T Haiman, Z AF Abel, T Haiman, Z BE Combes, F DesForets, GP TI The role of H-2 molecules in cosmological structure formation SO MOLECULAR HYDROGEN IN SPACE SE CAMBRIDGE CONTEMPORARY ASTROPHYSICS LA English DT Proceedings Paper CT International Conference on H(2) in Space CY SEP 28-OCT 01, 1999 CL PARIS, FRANCE SP PCMI-CNRS, Collaborat Computat Project 7, Observ Paris, Minist Affaires Etrangeres, Univ Cergy Pontoise, Univ Paris XI, Inst Astrophys Paris ID COLD DARK-MATTER; HYDROGEN MOLECULES; HIGH-REDSHIFT; INTERGALACTIC MEDIUM; NUMERICAL COSMOLOGY; RADIATIVE SHOCKS; GALAXY FORMATION; PRIMORDIAL GAS; EARLY UNIVERSE; STAR-FORMATION AB We review the relevance of H-2 molecules for structure formation in cosmology. Molecules are important at high-redshifts, when the first collapsed structures appear with typical temperatures of a few hundred Kelvin. In these chemically pristine clouds, radiative cooling is dominated by 112 molecules. As a result, H2 "astro-chemistry" is likely to determine the epoch when the first astrophysical objects appear. We summarize results of recent three-dimensional simulations. A discussion of the effects of feedback, and implications for the reionization of the universe is also given. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Abel, T (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 68 TC 6 Z9 6 U1 0 U2 1 PU CAMBRIDGE UNIV PRESS PI CAMBRIDGE PA THE PITT BUILDING, TRUMPINGTON ST, CAMBRIDGE CB2 1RP, CAMBS, ENGLAND BN 0-521-78224-4 J9 CAM CONTEMP ASTROPHY PY 2000 BP 237 EP 246 DI 10.1017/CBO9780511564635.038 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BT46Z UT WOS:000173071700035 ER PT S AU Gavrila, M AF Gavrila, M BE DiMauro, LF Freeman, RR Kulander, KC TI Stabilization of atoms in ultra-strong laser fields, a decade later SO MULTIPHOTON PROCESSES SE AIP Conference Proceedings LA English DT Proceedings Paper CT 8th International Conference on Multiphoton Processes (ICOMP VIII) CY OCT 03-08, 1999 CL MONTEREY, CA SP Univ Calif Davis, Dept Appl Sci, Lawrence Livermore Natl Lab, Phys Directorate, Natl Sci Fdn, Spectra Phys & Posit Light Corp ID FREQUENCY FLOQUET-THEORY; RANGE MODEL ATOM; ADIABATIC STABILIZATION; HYDROGEN-ATOM; MULTIPHOTON PROCESSES; INTENSE FIELDS; BOUND-STATE; SUPERINTENSE; IONIZATION; POLARIZATION AB This overview presents basic notions on atomic stabilization, some new illustrative results, as well as the recent controversy it has stirred. We start with quasistationary (adiabatic) stabilization (QS), the original form in which the concept has emerged from high-frequency Floquet theory (HFFT). QS designates the property of the high-frequency ionization rates to decrease with intensity beyond some critical high value of the latter. Other forms of Floquet theory (Sturmian basis diagonalization, close coupling in the angular momentum basis, R-matrix) have confirmed the existence of QS, and obtained concordant numerical values for the rates of H. The experimental manifestation of QS can be obtained with adiabatically varying pulses. Dynamic stabilization (DS), on the other hand, is the general form of the phenomenon, covering also the case of rapidly turned-on pulses. It designates the fact that, for wave-packet solutions of the time-dependent Schrodinger equation, the ionization probability of an atomic electron at the end of a laser pulse of given shape and length, starts decreasing (albeit in an oscillatory manner) beyond a certain critical value of the peak intensity. At still higher intensities, a "destabilization" regime was found, in which the ionization probability increases slowly to 1. We illustrate this behavior with recent results. Further, we give an interpretation of DS based on the expansion of Schrodinger wave packets in terms of Floquet eigenstates ("multistate Floquet theory"). The interpretation relies on the fact that the Floquet states involved manifest QS, that several of them may be populated during the turn-on of the pulse ("shake-up"), and that, if the turn-on is very rapid, the initial population can be projected directly into the continuum ("shake-off"). We also comment on the controversy around DS in recent years, originating, on the one hand, in numerical results disagreeing with mainstream calculations, and, on the other, in results from mathematical physics. The experimental evidence on stabilization is presented subsequently: two state of the of the art experiments have been performed on low-lying Rydberg states. Finally, perspectives are considered, and the advent of VUV-FEL light sources is signalled as a crucial step towards the experimental study of the ground state stabilization of H. The message of the overview is that, on the basis of existing information, (nonrelativistic) atomic stabilization is in good shape, and further research is desirable to reveal its potential. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Gavrila, M (reprint author), Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. NR 52 TC 13 Z9 13 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-946-7 J9 AIP CONF PROC PY 2000 VL 525 BP 103 EP 128 PG 26 WC Optics; Physics, Applied; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA BQ66W UT WOS:000089140300010 ER PT B AU Finn, B AF Finn, B BE Lindqvist, S TI Context and controversy SO MUSEUMS OF MODERN SCIENCE SE NOBEL SYMPOSIUM LA English DT Proceedings Paper CT Nobel Symposium on Museums of Modern Science CY MAY 29-30, 1999 CL ROYAL SWEDISH ACAD SCI, STOCKHOLM, SWEDEN SP Royal Swedish Acad Sci, Ctr Hist Sci, Nobel Museum HO ROYAL SWEDISH ACAD SCI C1 Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU SCIENCE HISTORY PUBLICATIONS/ USA PI SAGAMORE BEACH PA C/O WATSON PUBLISHING INTL, BOX 1248, SAGAMORE BEACH, MA 02562-1248 USA BN 0-88135-297-7 J9 NOBEL SYMP PY 2000 VL 112 BP 151 EP 158 PG 8 WC Art; History & Philosophy Of Science SC Art; History & Philosophy of Science GA BQ57A UT WOS:000088786600014 ER PT J AU Soon, W Baliunas, S Posmentier, ES Okeke, P AF Soon, W Baliunas, S Posmentier, ES Okeke, P TI Variations of solar coronal hole area and terrestrial lower tropospheric air temperature from 1979 to mid-1998: astronomical forcings of change in earth's climate? SO NEW ASTRONOMY LA English DT Article DE Sun : activity; Sun : corona; Sun : magnetic fields; Sun : particle emission; solar wind; solar-terrestrial relations ID COSMIC-RAY MODULATION; MIDDLE ATMOSPHERE; MASS EJECTIONS; IRRADIANCE VARIATIONS; SURFACE-TEMPERATURE; SUNSPOT CYCLE; VARIABILITY; CIRCULATION; WIND; FLUX AB The temperature anomaly of the terrestrial lower troposphere, inferred from the Microwave Sounding Unit (MSU) radiometers, is found to be inversely correlated with the area of the Sun covered by coronal holes. The correlation between the monthly time series of global tropospheric temperature anomaly and total coronal hole area from January 1979 to April 1998 has a Pearson coefficient of -0.46, which is different from zero at a 95% confidence level. Physical reasonings for the explained and unexplained parts of the correlation are discussed. The coronal hole area is a physical proxy for both the global-scale, 22-yr geometrical and shorter-term, dynamical components of the cosmic ray modulation, as well as the corpuscular emission of the Sun. Other solar parameters that may indicate a solar radiative effect on climate are also evaluated. It is concluded that variable fluxes either of solar charged particles or cosmic rays modulated by the solar wind, or both, may influence the terrestrial tropospheric temperature on timescale of months to years. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Long Isl Univ, Dept Phys, Brooklyn, NY 11201 USA. Long Isl Univ, Dept Math, Brooklyn, NY 11201 USA. Univ Nigeria, Dept Phys, Nsukka, Nigeria. Univ Nigeria, Dept Astron, Nsukka, Nigeria. Univ Pertanian Malaysia, Fac Sci & Environm Studies, Serdang 43400, Selangor, Malaysia. RP Soon, W (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM wsoon@cfa.harvard.edu; sbaliunas@cfa.harvard.edu; posmentier@mindspring.com; misunn@aol.com NR 88 TC 39 Z9 41 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1384-1076 J9 NEW ASTRON JI New Astron. PD JAN PY 2000 VL 4 IS 8 BP 563 EP 579 DI 10.1016/S1384-1076(00)00002-6 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 291JU UT WOS:000085731600001 ER PT J AU Kroupa, P AF Kroupa, P TI Constraints on stellar-dynamical models of the Orion Nebula Cluster SO NEW ASTRONOMY LA English DT Article DE binaries : general; stars : formation; open clusters and associations : individual (Orion nebula cluster, M42) ID TRAPEZIUM CLUSTER; STAR-FORMATION; CORE AB The results obtained by Kroupa, Petr & McCaughrean (1999) for specific models of young compact binary-rich clusters are generalised using dynamical scaling relations, to infer the candidate set of possible birth models leading to the Orion Nebula Cluster (ONC), of which the Trapezium Cluster is the core. It is found that candidate sets of solutions exist which allow the ONC to be in virial equilibrium, expanding or contracting. The range of possible solutions is quite narrow. These results will serve as guidelines for future, CPU-intensive calculations of the stellar-dynamical and astrophysical evolution of the entire ONC. These, in turn, will be essential to quantify observables that will ultimately discriminate between models, thus allowing us to understand if the ONC is in the process of assembling a rich Galactic cluster, and, if this is the case, how it occurs. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Kroupa, P (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM pkroupa@cfa.harvard.edu NR 25 TC 34 Z9 34 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1384-1092 J9 NEW ASTRON JI New Astron. PD MAR 8 PY 2000 VL 4 IS 8 BP 615 EP 624 DI 10.1016/S1384-1076(99)00048-2 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 291JU UT WOS:000085731600005 ER PT J AU Korine, C Kalko, EKV Herre, EA AF Korine, C Kalko, EKV Herre, EA TI Fruit characteristics and factors affecting fruit removal in a Panamanian community of strangler figs SO OECOLOGIA LA English DT Article DE Ficus; frugivory; fruit removal; seed dispersal; bats; birds; coadaptation ID BIRD-DISPERSED PLANTS; SEED DISPERSAL; ARTIBEUS-JAMAICENSIS; FRUGIVOROUS BIRDS; FICUS; FOREST; BATS; TREE; COMPETITION; FECUNDITY AB We describe fruiting characteristics for 12 species in a community of strangler figs (Moraceae: Urostigma) studied in Panama. We quantify diurnal and nocturnal removal rates and proportions of fruits removed, and relate them to the activities of the main dispersers of the figs: bats and birds. These results combined with previous studies show that there are clear differences between fig species with fruit that ripen red and those with fruit that remain green(ish). In the red-fruited species, the fruit are small, ripen asynchronously over relatively long periods, produce little scent, and are mainly taken during the day by birds. In contrast, in the green(ish)-fruited species, the fruits are larger, span a range of sizes, ripen relatively synchronously, produce very distinctive aromas, and are mainly taken at night by bats. This dichotomy in fruiting characteristics suggests coadaptive links between groups of dispersers and different species within the genus Ficus. All fig species produce a range of fruit crop sizes (10-155 fuits/m(2) canopy area) of which a high proportion were removed by seed dispersers (>80%). Removal rates (fruit removed per day) were positively correlated with crop size, suggesting that trees with large crop size attract more frugivores. Removal rates of green-fruited figs were significantly lower and persistence and abortion of ripe fruit were significant higher around full moon, apparently due to the reduced activity of bats. We further estimate the number of bats that are sustained by a tree fruit crop and account for the observed fruit removal. We then discuss the evidence for coadaptation between different groups of figs and their seed dispersers, Finally, we consider the conservation implications for figs as keystone resources in tropical forests. C1 Smithsonian Trop Res Inst, Balboa, Panama. Univ Tubingen, D-72076 Tubingen, Germany. RP Korine, C (reprint author), Ben Gurion Univ Negev, Jacob Blaustein Inst Desert Res, IL-84990 Midreshet Ben Gurion, Israel. EM ckorine@bgumail.bgu.ac.il RI Korine, Carmi/F-4116-2012 NR 63 TC 93 Z9 97 U1 5 U2 20 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0029-8549 EI 1432-1939 J9 OECOLOGIA JI Oecologia PY 2000 VL 123 IS 4 BP 560 EP 568 DI 10.1007/PL00008861 PG 9 WC Ecology SC Environmental Sciences & Ecology GA 333WT UT WOS:000088154300015 PM 28308765 ER PT B AU Geary, JC AF Geary, JC BE Amico, P Beletic, JW TI The 72-channel SAO Megacam: Design to PC boards SO OPTICAL DETECTORS FOR ASTRONOMY II: STATE-OF-THE-ART AT THE TURN OF THE MILLENNIUM SE ASTROPHYSICS AND SPACE SCIENCE LIBRARY LA English DT Proceedings Paper CT 4th European-Southern-Observatory Charge Coupled Devices Workshop on Optical Detectors for Astronomy CY SEP 13-16, 1999 CL GARCHING, GERMANY SP European SO Observ AB Prototyping of the massively parallel 72-channel SAO Megacam has been completed and we are preparing the printed circuit boards for initial deployment. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Geary, JC (reprint author), Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6536-4 J9 ASTROPHYS SPACE SC L PY 2000 VL 252 BP 407 EP 411 PG 5 WC Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BR63J UT WOS:000166990000040 ER PT S AU Jacobs, VL AF Jacobs, VL BE Shirley, EL Chelikowsky, JR Louie, SG Martinez, G TI Computation of optical properties for quantized electronic systems SO OPTICAL PROPERTIES OF MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on the Optical Properties of Materials at the 1999 MRS Fall Meeting CY NOV 30-DEC 02, 1999 CL BOSTON, MA SP Mat Res Soc ID DIELECTRONIC SATELLITE SPECTRA; PLASMAS; TRANSITIONS; RADIATION AB A density-matrix description has been developed to treat relaxation (decoherence) phenomena during resonant and non-resonant radiative transitions of quantized electronic systems, including many-electron atoms and quantum-confinement systems (e. g., semiconductor microstructures). Radiative and collisional relaxation phenomena have been treated using Liouville-space projection-operator techniques. Both time-independent (resolvent-operator) and time-dependent (equation-of-motion) formulations have been developed. The self-energy operators that occur in these formulations can provide the fundamental basis for a self-consistent determination of the non-equilibrium and coherent electronic-state kinetics together with the homogeneous spectral-line shapes. This density-matrix description can be adapted for the computer simulation of electromagnetic processes. From first-principles electronic-structure calculations or from semi-empirical approaches, the parameters describing the elementary collisional and radiative interactions can be evaluated and organized into the basic data set for the application of the density-matrix description. The final product is a theoretical prediction for the linear or non-linear optical absorption or emission spectrum corresponding to a given set of values for the appropriate physical variables, such as temperatures, densities, and electric or magnetic field strengths. C1 USN, Res Lab, Div Mat Sci & Technol, Ctr Computat Mat Sci, Washington, DC 20375 USA. RP Jacobs, VL (reprint author), Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-487-4 J9 MATER RES SOC SYMP P PY 2000 VL 579 BP 123 EP 128 PG 6 WC Materials Science, Characterization & Testing; Optics; Physics, Applied; Physics, Condensed Matter SC Materials Science; Optics; Physics GA BR76J UT WOS:000167460000015 ER PT J AU Laurance, WF Vasconcelos, HL Lovejoy, TE AF Laurance, WF Vasconcelos, HL Lovejoy, TE TI Forest loss and fragmentation in the Amazon: implications for wildlife conservation SO ORYX LA English DT Article DE Amazon forest; Brazil; deforestation; edge effects; habitat fragmentation; hunting; logging; tropical rain forest; wildlife ID TROPICAL RAIN-FOREST; BRAZILIAN AMAZON; HABITAT FRAGMENTATION; TREE COMMUNITIES; LAND-USE; DYNAMICS; EXTINCTION; PATTERNS AB Amazonian forests are experiencing rapid, unprecedented changes that are having major impacts on wildlife, regional hydrology and the global climate. Rates of deforestation and logging have accelerated in recent years and patterns of forest loss are changing, with extensive new highways providing conduits for settlers and loggers into the heart of the Amazon basin. These myriad changes are causing widespread fragmentation of forests. Fragmented landscapes in the Amazon experience diverse changes in forest dynamics, structure, composition and microclimate, and are highly vulnerable to droughts and fires-alterations that negatively affect a wide variety of animal species. Ln human-dominated lands intensive hunting may interact synergistically with fragmentation to further threaten wildlife populations. C1 Natl Inst Res Amazon, Biol Dynam Forest Fragments Project, INPA, BR-69011970 Manaus, Amazonas, Brazil. Smithsonian Inst, Natl Museum Nat Hist, Biodivers Program, Washington, DC 20560 USA. RP Laurance, WF (reprint author), Natl Inst Res Amazon, Biol Dynam Forest Fragments Project, INPA, CP 478, BR-69011970 Manaus, Amazonas, Brazil. RI Laurance, William/B-2709-2012; Vasconcelos, Heraldo/C-3353-2013 OI Vasconcelos, Heraldo/0000-0001-6969-7131 NR 69 TC 67 Z9 71 U1 13 U2 105 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0030-6053 J9 ORYX JI Oryx PD JAN PY 2000 VL 34 IS 1 BP 39 EP 45 DI 10.1046/j.1365-3008.2000.00094.x PG 7 WC Ecology SC Environmental Sciences & Ecology GA 285AQ UT WOS:000085366300008 ER PT J AU Behrensmeyer, AK Kidwell, SM Gastaldo, RA AF Behrensmeyer, AK Kidwell, SM Gastaldo, RA TI Taphonomy and paleobiology SO PALEOBIOLOGY LA English DT Review ID SILICICLASTIC-CARBONATE SETTINGS; PROTEROZOIC-CAMBRIAN TRANSITION; DECIDUOUS FOREST COMMUNITIES; MOLLUSCAN DEATH ASSEMBLAGES; EARLY ARCHAEOLOGICAL SITES; DINOSAUR-PROVINCIAL-PARK; JUDITH RIVER FORMATION; FOSSIL RECORD; BURGESS-SHALE; LEAF-LITTER AB Taphonomy plays diverse roles in paleobiology. These include assessing sample quality relevant to ecologic, biogeographic, and evolutionary questions, diagnosing the roles of Various taphonomic agents, processes and circumstances in generating the sedimentary and fossil records, and reconstructing the dynamics of organic recycling over time as a part of Earth history. Major advances over the past 15 years have occurred in understanding (1) the controls on preservation, especially the ecology and biogeochemistry of soft-tissue preservation, and the dominance of biological versus physical agents in the destruction of remains from all major taxonomic groups (plants, invertebrates, vertebrates); (2) scales of spatial and temporal resolution, particularly the relatively minor role of out-of-habitat transport contrasted with the major effects of time-averaging; (3) quantitative compositional fidelity: that is, the degree to which different types of assemblages reflect the species composition and abundance of source faunas and floras; and (4) large-scale variations through time in preservational regimes (megabiases), caused by the evolution of new body-plans and behavioral capabilities, and by broad-scale changes in climate, tectonics, and geochemistry of Earth surface systems. Paleobiological questions regarding major trends in biodiversity, major extinctions and recoveries, timing of cladogenesis and rates of evolution, and the role of environmental forcing in evolution all entail issues appropriate for taphonomic analysis, and a wide range of strategies are being developed to minimize the impact of sample incompleteness and bias. These include taphonomically robust metrics of paleontologic patterns, gap analysis, equalizing samples via rarefaction, inferences about preservation probability, isotaphonomic comparisons, taphonomic control taxa, and modeling of artificial fossil assemblages based on modern analogues. All of this work is yielding a more quantitative assessment of both the positive and negative aspects of paleobiological samples. Comparisons and syntheses of patterns across major groups and over a wider range of temporal and spatial scales present a challenging and exciting agenda for taphonomy in the coming decades. C1 Smithsonian Inst, Natl Museum Amer Hist, Dept Paleobiol, Washington, DC 20560 USA. Univ Chicago, Dept Geophys Sci, Chicago, IL 60637 USA. Colby Coll, Dept Geol, Waterville, ME 04901 USA. RP Behrensmeyer, AK (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Dept Paleobiol, MRC 121, Washington, DC 20560 USA. EM Behrensmeyer.Kay@NMNH.SI.edu; skidwell@midway.uchicago.edu; ragastal@colby.edu NR 449 TC 251 Z9 261 U1 8 U2 79 PU PALEONTOLOGICAL SOC INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044 USA SN 0094-8373 J9 PALEOBIOLOGY JI Paleobiology PY 2000 VL 26 IS 4 SU S BP 103 EP 147 DI 10.1666/0094-8373(2000)26[103:TAP]2.0.CO;2 PG 45 WC Biodiversity Conservation; Ecology; Evolutionary Biology; Paleontology SC Biodiversity & Conservation; Environmental Sciences & Ecology; Evolutionary Biology; Paleontology GA 394VG UT WOS:000166543500006 ER PT J AU Jackson, JBC Johnson, KG AF Jackson, JBC Johnson, KG TI Life in the last few million years SO PALEOBIOLOGY LA English DT Review ID TROPICAL AMERICAN MOLLUSKS; KELP FOREST COMMUNITIES; SANTA-BARBARA BASIN; CORAL-REEF; CONFIDENCE-INTERVALS; ENVIRONMENTAL-CHANGE; CRYPTIC SPECIATION; NORTH-ATLANTIC; CICHLID FISHES; CLIMATE CHANGE AB The excellent fossil record of the past few million years, combined with the overwhelming similarity of the biota to extant species, provides an outstanding opportunity for understanding paleoecological and macroevolutionary patterns and processes within a rigorous biological framework. Unfortunately, this potential has not been fully exploited because of lack of well-sampled time series and adequate statistical analysis. Nevertheless, four basic patterns appear to be of general significance. First, a major pulse of extinction occurred 1-2 m.y. ago in many ocean basins, more or less coincident with the intensification of glaciation in the Northern Hemisphere. Rates of origination also increased greatly but were more variable in magnitude and timing. The fine-scale correlation of these evolutionary events with changes in climate is poorly understood. Similar events probably occurred on land but have not been rested adequately. Second, rates of origination and extinction in the oceans waned after the pulse of extinction, especially during the past 1 m.y. Thus, most marine species originated long before the Pleistocene under very different environmental circumstances, suggesting that they are "exapted" rather than adapted to their present ecological circumstances. The same may be true for many terrestrial groups, but not for the mammals or fresh-water fishes that have continued to undergo speciation throughout the Pleistocene. Third, community membership of late Pleistocene coral reef communities was more stable than expected by chance. These are the only paleoecological data adequate to test hypotheses of community stability, so that we do not know whether community structure involving other taxa or environments typically reflects more than the collective behavior of individual species distributions. Regardless, the strong evidence for nearly universal exaptation of ecological characteristics argues strongly against ideas of coevolution of species in communities. Finally, ecological communities were profoundly altered by human activities long before modern ecological studies began. Holocene paleontological, archeological, and historical data constitute the only ecological baseline for "pristine" ecological communities before significant human disturbance. Holocene records should be much more extensively used as a baseline for Recent ecological studies and for conservation and management. C1 Univ Calif San Diego, Scripps Inst Oceanog, Div Geosci, La Jolla, CA 92093 USA. Univ Calif San Diego, Scripps Inst Oceanog, Div Marine Biol Res, La Jolla, CA 92093 USA. Smithsonian Trop Res Inst, Balboa, Panama. Univ Calif San Diego, Scripps Inst Oceanog, Geosci Res Div, La Jolla, CA 92093 USA. RP Jackson, JBC (reprint author), Univ Calif San Diego, Scripps Inst Oceanog, Div Geosci, La Jolla, CA 92093 USA. NR 131 TC 56 Z9 64 U1 1 U2 18 PU PALEONTOLOGICAL SOC INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044 USA SN 0094-8373 J9 PALEOBIOLOGY JI Paleobiology PY 2000 VL 26 IS 4 SU S BP 221 EP 235 DI 10.1666/0094-8373(2000)26[221:LITLFM]2.0.CO;2 PG 15 WC Biodiversity Conservation; Ecology; Evolutionary Biology; Paleontology SC Biodiversity & Conservation; Environmental Sciences & Ecology; Evolutionary Biology; Paleontology GA 394VG UT WOS:000166543500010 ER PT B AU Goddard, I AF Goddard, I BE Nichols, JD TI The historical origins of Cheyenne inflections SO PAPERS OF THE THIRTY-FIRST ALGONQUIAN CONFERENCE SE PAPERS OF THE ALGONQUIAN CONFERENCE LA English DT Proceedings Paper CT 31st Algonquian Conference held in Conjunction with the 9th Annual Woodland Nations History Conference CY OCT 28-31, 1999 CL LAFAYETTE, IN C1 Smithsonian Inst, Washington, DC 20560 USA. NR 28 TC 1 Z9 1 U1 0 U2 0 PU UNIV MANITOBA PRESS PI WINNIPEG PA 244 ENGINEERING BLDG, WINNIPEG, MANITOBA R3T 2N2, CANADA J9 PAP ALGON CONF PY 2000 VL 31 BP 77 EP 129 PG 53 WC Anthropology; Language & Linguistics SC Anthropology; Linguistics GA BT57F UT WOS:000173398700006 ER PT J AU Carlstrom, JE Joy, MK Grego, L Holder, GP Holzapfel, WL Mohr, JJ Patel, S Reese, ED AF Carlstrom, JE Joy, MK Grego, L Holder, GP Holzapfel, WL Mohr, JJ Patel, S Reese, ED TI Imaging the Sunyaev-Zel'dovich effect SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT 109th Nobel Symposium on Particle Physics and the Universe CY AUG 20-25, 1998 CL HAGA SLOTT, SWEDEN SP Nobel Fdn ID X-RAY; CLUSTERS; COMPTONIZATION; ABELL-2163; SUPERNOVAE; GALAXIES; CONSTANT; UNIVERSE; GHZ AB We report on results of interferometric imaging of the Sunyaev-Zel'dovich Effect (SZE) with the OVRO and BIMA mm-arrays. Using low-noise cm-wave receivers on the arrays, we have obtained high quality images for 27 distant galaxy clusters. We review the use of the SZE as a cosmological tool. Gas mass fractions derived from the SZE data are given for 18 of the clusters, as well as the implied constraint on the matter density of the universe, Omega(M). We find Omega(M)h(100) less than or equal to 0.22(-0.03)(+0.05). A best guess for the matter density obtained by assuming a reasonable value for the Hubble constant and also by attempting to account for the baryons contained in the galaxies as well as those lost during the cluster formation process gives Omega(M) similar to 0.25. We also give preliminary results for the Hubble constant. Lastly, the power for investigating the high redshift universe with a non-targeted high sensitivity SZE survey is discussed and an interferometric survey is proposed. C1 Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. RP Carlstrom, JE (reprint author), Univ Chicago, Dept Astron & Astrophys, 5640 S Ellis Ave, Chicago, IL 60637 USA. RI Holzapfel, William/I-4836-2015 NR 33 TC 38 Z9 39 U1 0 U2 0 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 2000 VL T85 BP 148 EP 155 DI 10.1238/Physica.Topical.085a00148 PG 8 WC Physics, Multidisciplinary SC Physics GA 321ER UT WOS:000087442900019 ER PT J AU Jamieson, MJ Dalgarno, A Zygelman, B Krstic, PS Schultz, DR AF Jamieson, MJ Dalgarno, A Zygelman, B Krstic, PS Schultz, DR TI Collisions of ground-state hydrogen atoms SO PHYSICAL REVIEW A LA English DT Article ID MOLECULE; CURVES; MASER AB We derive an expression for the diffusion cross section of identical atoms and use it in a report of diffusion, viscosity, total, spin-change, frequency-shift, and broadening cross sections in hydrogen, calculated with improved interaction potentials. We also report some total cross sections for spin-polarized hydrogen. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Glasgow, Dept Comp Sci, Glasgow G12 8QQ, Lanark, Scotland. Univ Nevada, Dept Phys, Las Vegas, NV 89154 USA. RP Jamieson, MJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 27 TC 4 Z9 4 U1 1 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD JAN PY 2000 VL 61 IS 1 BP art. no. EP 014701 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 281PA UT WOS:000085168800075 ER PT J AU Yoshino, K Thorne, AP Murray, JE Ito, K Matsui, T Leung, KWS Cheung, ASC Imajo, T AF Yoshino, K Thorne, AP Murray, JE Ito, K Matsui, T Leung, KWS Cheung, ASC Imajo, T TI The application of a VUV-FT spectrometer and synchrotron radiation source to measurements of the NO and O-2 bands at 295 K SO PHYSICS AND CHEMISTRY OF THE EARTH PART C-SOLAR-TERRESTIAL AND PLANETARY SCIENCE LA English DT Article ID SCHUMANN-RUNGE BANDS; FOURIER-TRANSFORM SPECTROSCOPY; CROSS-SECTION MEASUREMENTS; HERZBERG-I BANDS; OSCILLATOR-STRENGTHS; HIGH-RESOLUTION; VACUUM-ULTRAVIOLET AB Current research on the Earth's upper atmosphere requires molecular parameters of unprecedented detail and accuracy. Models of the vacuum-ultraviolet (VUV) absorbing properties of the atmosphere call for absorption cross sections with details on the scale of the Doppler linewidths. As a consequence, spectroscopic data at resolving powers of the order of 10(6) are needed. Current particular needs are for ultra high resolution absorption cross section data for some bands of NO and O-2 in the UV to VUV region. To meet these requirements, we moved the VUV Fourier transform spectrometer at Imperial College, London to a synchrotron radiation facility (Photon Factory, KEK, Japan) and measured VUV photoabsorption cross sections of NO from 195 to 160 nm and O-2, from 185 to 175 nm. (C) 2000 Elsevier Science Ltd. Ail rights reserved. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BZ, England. KEK, Photon Factory, Tsukuba, Ibaraki 305, Japan. Univ Hong Kong, Hong Kong, Hong Kong, Peoples R China. Kyushu Univ, Fukuoka 812, Japan. RP Yoshino, K (reprint author), Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RI Cheung, Allan/D-3059-2009 NR 15 TC 1 Z9 2 U1 1 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1464-1917 J9 PHYS CHEM EARTH PT C JI Phys. Chem. Earth Pt. C-Solar-Terr. Planet. Sci. PY 2000 VL 25 IS 3 BP 199 EP 201 DI 10.1016/S1464-1917(00)00006-4 PG 3 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 296WX UT WOS:000086050700005 ER PT S AU Shurgalin, M Murray, AJ MacGillivray, WR Standage, MC Madison, D Winkler, KD Bray, I AF Shurgalin, M Murray, AJ MacGillivray, WR Standage, MC Madison, D Winkler, KD Bray, I BE Itikawa, Y Okuno, K TanakaA, H Yagishita, A Matsuzawa, M TI Angular momentum transferred in inelastically scattered P to S state electron-atom collisions SO PHYSICS OF ELECTRONIC AND ATOMIC COLLISIONS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 21st International Conference on the Physics of Electronic and Atomic Collisions (21st ICPEAC) CY JUL 22-27, 1999 CL SENDAI, JAPAN SP Soc Atom Collis Res, Phys Soc Japan, Chem Soc Japan, Int Union Pure & Appl Phys, Sedai City, Atom Energy Soc Japan, Japan Atom Energy Res Inst, Matsuo Fdn, Inoue Fdn Sci, Casio Sci Promot Fdn, Iwatani Naoji Fdn, Kao Fdn Arts & Sci, Diawa Anglo Japanese Fdn, Sci Measurements Res Fdn, Asahi Glass Fdn, Ishikawa Fdn Carbon Sci & Technol ID EXCITATION; ORIENTATION; IMPACT AB Coherent laser preparation of atoms has been employed in superelastic and inelastic electron scattering from the excited 3(2)P(3/2) state of sodium. This allows Atomic Collision Parameters to be deduced for the 3S to 3P and 3P to 4S transitions respectively. By employing micro-reversibility, a long standing proposal relating the sign of the transferred angular momentum to the sense of energy transfer has been tested, and is not supported in general by experiment. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Shurgalin, M (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Bray, Igor/B-8586-2009 OI Bray, Igor/0000-0001-7554-8044 NR 9 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-777-4 J9 AIP CONF PROC PY 2000 VL 500 BP 436 EP 441 PG 6 WC Physics, Atomic, Molecular & Chemical SC Physics GA BP70Y UT WOS:000085936100040 ER PT J AU Gehrig, HH Winter, K Cushman, J Borland, A Taybi, T AF Gehrig, HH Winter, K Cushman, J Borland, A Taybi, T TI An improved RNA isolation method for succulent plant species rich in polyphenols and polysaccharides SO PLANT MOLECULAR BIOLOGY REPORTER LA English DT Article DE Aloe; Ananas; Clusia; crassulacean acid metabolism; Euphorbia; Kalanchoe; Opuntia; phenolic compounds; Pyrrosia; RNA extraction ID ACTIVE RIBONUCLEIC-ACID AB Isolation of high quality, high molecular weight RNA from plant tissues is complicated by high levels of polyphenols and polysaccharides which bind to and/or co-precipitate with RNA. Using high molecular weight polyethylene glycol (HMW-PEG), RNA was successfully isolated from plant species in which other RNA extraction methods and commercially available kits failed to deliver suitable results. We tested various buffer systems and isolation conditions with and without PEG or PVP (polyvinylpyrrolidone) using tissue from species of Aloe. Ananas, Clusia, Euphorbia, Kalanchoe. Opuntia, and Pyrrosia, all of which contain high amounts of phenolic compounds and/or polysaccharides. HMW-PEG was found to be more effective than PVP in removing these compounds. RNA extraction using HMW-PEG resulted in RNA of high quality from all species investigated, as indicated by UV light absorption profiles, and also yielded PCR amplification products after reverse transcription. C1 Smithsonian Trop Res Inst, Balboa, Panama. Univ Nevada, Reno, NV 89557 USA. Univ Newcastle Upon Tyne, Dept Agr & Environm Sci, Newcastle Upon Tyne NE1 7RU, Tyne & Wear, England. NR 12 TC 82 Z9 112 U1 1 U2 14 PU INT SOC PLANT MOLECULAR BIOLOGY PI ATHENS PA UNIV GEORGIA, DEPT BIOCHEMISTRY, ATHENS, GA 30602 USA SN 0735-9640 J9 PLANT MOL BIOL REP JI Plant Mol. Biol. Rep. PY 2000 VL 18 IS 4 BP 369 EP 376 DI 10.1007/BF02825065 PG 8 WC Biochemical Research Methods; Plant Sciences SC Biochemistry & Molecular Biology; Plant Sciences GA 393BM UT WOS:000166449400008 ER PT J AU Roubik, DW AF Roubik, DW TI Deceptive orchids with Meliponini as pollinators SO PLANT SYSTEMATICS AND EVOLUTION LA English DT Article DE neotropical orchids; Meliponini; mimicry; pollination ID BEE AB Visitation of orchids by Meliponini (stingless bees) is confirmed only in 13 Melipona, Partamona and Trigona, for Xylobium and Maxillaria, with the addition of Trigona fulviventris visiting Ionopsis. Some bees evinced multiple floral visitation by carrying several stipes and viscidia from pollinaria, thus may cause seed set. None foraged pseudopollen, nor is collection of this substance by bees verified. Meliponine-visited orchids had pollinia in quartets with emplacement on the bee's scutellum, possibly devices for pollinia survival on a social bee passing through its nest. Further, orchids produced no nectar, but bees repeatedly came to flowers. A testable basis for the orchid-meliponine relationship is mimicry of rewarding resources, or bee pheromone mimicry, recently documented for some honey bees. Meliponine pheromone analogs (nerol and 2-heptanol) are here noted for Maxillaria, but lack of foraging with pheromones by Melipona suggests multiple avenues of mimicry by orchids, including alarm pheromone and carrion mimicry. C1 Smithsonian Trop Res Inst, Balboa, Panama. RP Roubik, DW (reprint author), Smithsonian Trop Res Inst, Apartado 2072, Balboa, Panama. NR 27 TC 17 Z9 21 U1 0 U2 19 PU SPRINGER-VERLAG WIEN PI VIENNA PA SACHSENPLATZ 4-6, PO BOX 89, A-1201 VIENNA, AUSTRIA SN 0378-2697 J9 PLANT SYST EVOL JI Plant Syst. Evol. PY 2000 VL 222 IS 1-4 BP 271 EP 279 DI 10.1007/BF00984106 PG 9 WC Plant Sciences; Evolutionary Biology SC Plant Sciences; Evolutionary Biology GA 332FX UT WOS:000088064500015 ER PT J AU Krupnik, I AF Krupnik, I TI Reindeer pastoralism in modern Siberia: research and survival during the time of crash SO POLAR RESEARCH LA English DT Article; Proceedings Paper CT Human Role in Reindeer/Caribou Systems Workshop CY FEB 10-14, 1999 CL ROVANICMI, FINLAND AB In many areas across Siberia, the reindeer herding economy of the native people went into a deep recession during the post-Soviet transition of the 1990s. However, as a larger cross-section of data indicates, the reindeer stock decline is not a universal phenomenon. Nor is the present-day crisis in native Siberian herding economies an unprecedented event, as pastoralists did suffer tremendously in "traditional times", due to the devastating epizootics and other natural disasters, and even more so, during the Soviet-induced collectivization. While such a historical review by no means diminishes the scale of the present-day crisis in native herding economies, it helps to identify both the experience and traditional adaptations once used by the native Siberians during the previous times of hardship. Of those, the most efficient were: maintaining cultural and ecological diversity in local herding systems; the ability to shift quickly between nomadic and sedentary subsistence patterns; and preservation of the indigenous herding tradition and the "core" nomadic population as the invaluable source of cultural knowledge, technological expertise, and of domestic reindeer stock for ultimate recovery. The modern situation in Siberia, in fact, favours increased local diversity and helps to produce a steady stream of new "winners" as well as new "losers." This new experience has to be comprehensively documented, to produce both a reliable general overview and a detailed summary of the specific regional and local transitions. C1 Smithsonian Inst, Arctic Studies Ctr, Washington, DC 20560 USA. RP Krupnik, I (reprint author), Smithsonian Inst, Arctic Studies Ctr, Washington, DC 20560 USA. NR 50 TC 18 Z9 19 U1 1 U2 4 PU NORWEGIAN POLAR INST PI OSLO PA MIDDELTHUNS GATE 29, POSTBOKS 5072 MAJORSTUA, 0301 OSLO, NORWAY SN 0800-0395 J9 POLAR RES JI Polar Res. PY 2000 VL 19 IS 1 BP 49 EP 56 DI 10.1111/j.1751-8369.2000.tb00327.x PG 8 WC Ecology; Geosciences, Multidisciplinary; Oceanography SC Environmental Sciences & Ecology; Geology; Oceanography GA 338QJ UT WOS:000088430500006 ER PT S AU Soon, W Baliunas, S Kondratyev, KY Idso, SB Posmentier, E AF Soon, W Baliunas, S Kondratyev, KY Idso, SB Posmentier, E BE Wilson, A TI Calculating the climatic impacts of increased CO(2): The issue of model validation SO PROCEEDINGS OF THE 1ST SOLAR AND SPACE WEATHER EUROCONFERENCE ON THE SOLAR CYCLE AND TERRESTRIAL CLIMATE SE ESA Special Publications LA English DT Proceedings Paper CT 1st Solar and Space Weather Euroconference on the Solar Cycle and Terrestrial Climate CY SEP 25-29, 2000 CL INST ASTROFIS CANARIAS, SANTA CRUZ TENERI, SPAIN SP European Commiss, Spanish Minist Sci & Technol, Cabildo Insular Santa Curz Tenerife, European Space Agcy, CajaCanarias, Ayuntamiento Danta Cruz Tenerife, Ayuntamiento La Laguna, Observ Paris HO INST ASTROFIS CANARIAS ID THERMOHALINE CIRCULATION; ATMOSPHERIC CO2; INTERANNUAL VARIATIONS; TEMPERATURE-CHANGES; SOLAR IRRADIANCE; CARBON-DIOXIDE; COUPLED MODEL; GCM; SURFACE; VARIABILITY AB It is commonly believed that increases in man-made greenhouse gases could cause large increases in surface and lower atmospheric temperatures with disastrous global and regional environmental consequences. Because the expected human-made climate forcings are relatively small when compared to various other natural (both internal and external) background and forcing factors, we focus on the important question of climate model validation. We review common deficiencies in general circulation model calculations of atmospheric temperature, surface temperature, precipitation and their complex space-time variability associated with the multiply interacting climate components and feedbacks. These deficiencies also impact our understanding of how Earth's climate responses to external forcing agents such as the natural variations of incoming radiant and particle energies linked to changes in the Sun. We also review examples of expected climatic effects of anthropogenic CO(2) forcing. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Soon, W (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM wsoon@cfa.harvard.edu NR 68 TC 1 Z9 1 U1 0 U2 4 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 BN 92-9092-693-7 J9 ESA SPEC PUBL PY 2000 VL 463 BP 243 EP 254 PG 12 WC Astronomy & Astrophysics; Meteorology & Atmospheric Sciences SC Astronomy & Astrophysics; Meteorology & Atmospheric Sciences GA BR99Z UT WOS:000168300800031 ER PT J AU Polhemus, DA AF Polhemus, DA TI A revision of the endemic Hawaiian reduviid genus Saicella Usinger, with descriptions of four new species (Heteroptera : Reduviidae : Emesinae) SO PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON LA English DT Article DE Reduviidae; Hawaiian islands; Saicella; new species; biogeography AB The Hawaiian genus Saicella is revised, and four new species are described: S, perkinsi from Oahu, S. lilinoe from Maul, S. kipahulu from Maul, and S, mulli from Hawaii. A key to species is provided, accompanied by distribution maps, habitus figures, and illustrations of key characters. C1 Smithsonian Inst, Dept Entomol, Washington, DC 20560 USA. RP Polhemus, DA (reprint author), Smithsonian Inst, Dept Entomol, MRC 105, Washington, DC 20560 USA. NR 5 TC 2 Z9 3 U1 0 U2 0 PU ENTOMOL SOC WASHINGTON PI WASHINGTON PA SMITHSONIAN INSTITUTION DEPT ENTOMOLOGY, WASHINGTON, DC 20560 USA SN 0013-8797 J9 P ENTOMOL SOC WASH JI Proc. Entomol. Soc. Wash. PD JAN PY 2000 VL 102 IS 1 BP 1 EP 20 PG 20 WC Entomology SC Entomology GA 275NE UT WOS:000084825600001 ER PT J AU Robbins, RK AF Robbins, RK TI The new world hairstreak genus Arawacus Kaye (Lepidoptera : Lycaenidae : Theclinae : Eumaeini) SO PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON LA English DT Article DE Thereus; Rekoa; Contrafacia; Dolymorpha; Polyniphes; Tigrinota; Solanaceae AB Even though Arawacus Kaye is widely used in works on North American butterflies, its characterization has been inconsistent and its included species have not been listed. Subterminally constricted tips of the papillae anales are proposed to be the best way to characterize Arawacus. They are consistent with the higher classification of the Thereus Section of the Eumaeini, to which Arawacus belongs. They are consistent with patterns of oviposition specificity. This characterization re-confirms that Polyniphes Kaye and Dolymorpha Holland are junior synonyms of Arawacus. Tigrinota Johnson is synonymized with Arawacus, new synonym. All nomenclaturally available specific names that belong to Arawacus are listed. C1 Smithsonian Inst, Museum Natl Hist Nat, Dept Entomol, Washington, DC 20560 USA. RP Robbins, RK (reprint author), Smithsonian Inst, Museum Natl Hist Nat, Dept Entomol, Washington, DC 20560 USA. NR 39 TC 3 Z9 5 U1 0 U2 0 PU ENTOMOL SOC WASHINGTON PI WASHINGTON PA SMITHSONIAN INSTITUTION DEPT ENTOMOLOGY, WASHINGTON, DC 20560 USA SN 0013-8797 J9 P ENTOMOL SOC WASH JI Proc. Entomol. Soc. Wash. PD JAN PY 2000 VL 102 IS 1 BP 162 EP 169 PG 8 WC Entomology SC Entomology GA 275NE UT WOS:000084825600016 ER PT J AU Paine, S Blundell, R Papa, DC Barrett, JW Radford, SJE AF Paine, S Blundell, R Papa, DC Barrett, JW Radford, SJE TI A Fourier transform spectrometer for measurement of atmospheric transmission at submillimeter wavelengths SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article ID ASTRONOMY AB We describe a Fourier transform spectrometer for measurements of atmospheric transmission in the spectral interval 300 GHz to 3.5 THz. This instrument has been developed to evaluate prospective sites for radio astronomical observations at frequencies above 1 THz. Measurements have been made on Mauna Kea, Hawaii, and at the site of the future Millimeter Array near Cerro Chajnantor in northern Chile, Chajnantor frequently exhibits significant transmission in atmospheric windows at frequencies above 1 THz. Here we outline the design and characteristics of the instrument, discuss data processing methods, and present sample measurements from Chajnantor. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Natl Radio Astron Observ, Tucson, AZ 85721 USA. RP Paine, S (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. OI radford, simon/0000-0001-9113-1660 NR 17 TC 56 Z9 56 U1 0 U2 1 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 JAN PY 2000 VL 112 IS 767 BP 108 EP 118 DI 10.1086/316497 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 279TP UT WOS:000085061500013 ER PT B AU Ransom, SM AF Ransom, SM BE Kramer, M Wex, N Wielebinski, R TI A fast search technique for binary pulsars SO PULSAR ASTRONOMY - 2000 AND BEYOND: IAU COLLOQUIUM 177 SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 177th IAU Colloquium on Pulsar Astronomy - 2000 and Beyond CY AUG 30-SEP 03, 1999 CL BONN, GERMANY SP Int Astronom Union, Deutsch Forschgsgemein, Max Planck Inst Radioastronom, Max Planck Inst Ecxtraterrest Phys AB I describe a computationally simple, efficient, and sensitive method to search long observations for pulsars in binary systems. The technique looks for orbitally induced sidebands in the power spectrum around a nominal spin frequency, enabling it to detect pulsars in high- or low-mass binaries with short orbital periods (P-orb less than or similar to 5 h). C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Ransom, SM (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS 10, Cambridge, MA 02138 USA. NR 3 TC 2 Z9 2 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-029-3 J9 ASTR SOC P PY 2000 VL 202 BP 43 EP 44 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ44S UT WOS:000088366000014 ER PT B AU Kalogera, V AF Kalogera, V BE Kramer, M Wex, N Wielebinski, R TI Close binaries with two compact objects SO PULSAR ASTRONOMY - 2000 AND BEYOND: IAU COLLOQUIUM 177 SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 177th IAU Colloquium on Pulsar Astronomy - 2000 and Beyond CY AUG 30-SEP 03, 1999 CL BONN, GERMANY SP Int Astronom Union, Deutsch Forschgsgemein, Max Planck Inst Radioastronom, Max Planck Inst Ecxtraterrest Phys ID NEUTRON-STAR BINARIES; PULSAR; SYSTEM; EVOLUTION AB The coalescence of close binary systems with two compact objects (neutron stars and black holes) are considered to be promising sources of gravitational waves for the currently built laser interferometers. Here, I review the current Galactic coalescence estimates derived both theoretically and empirically. I discuss the uncertainties involved as well as ways of obtaining an upper limit to the coalescence rate of two neutron stars. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Kalogera, V (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 21 TC 1 Z9 1 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-029-3 J9 ASTR SOC P PY 2000 VL 202 BP 579 EP 584 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ44S UT WOS:000088366000183 ER PT J AU Colinvaux, PA De Oliveira, PE Bush, MB AF Colinvaux, PA De Oliveira, PE Bush, MB TI Amazonian and neotropical plant communities on glacial time-scales: The failure of the aridity and refuge hypotheses SO QUATERNARY SCIENCE REVIEWS LA English DT Article; Proceedings Paper CT 1st PAGES Open Science Meeting CY APR 19-23, 1998 CL UNIV LONDON, LONDON, ENGLAND HO UNIV LONDON ID LATE-QUATERNARY; CLIMATIC CHANGES; CENTRAL BRAZIL; POLLEN RECORD; TEMPERATURE DEPRESSION; ECUADORIAN ANDES; TROPICAL FORESTS; LATE PLEISTOCENE; LAKE VALENCIA; PALM SWAMP AB Plants respond to Pleistocene climatic change as species, not as associations or biomes. This has been demonstrated unequivocally by paleobotanical data for temperate latitudes. In the far richer vegetations of the tropics species populations also fluctuated independently in response to climatic forcing, from their longlasting glacial states to the patterns of brief interglacials like the present and back again. We use pollen data to reconstruct the vegetation of the Amazon basin in oxygen isotope stages 3 and 2 of the last glaciation in order to measure how the plant populations of the Amazon responded to the global warming at the onset of the Holocene. We find that plant communities of the neotropics vent copious pollen to lake sediments and that this pollen yields powerful signals for community composition. Three continuous sedimentary records reaching through oxygen isotope stage 2 are available from the Amazon lowlands, those from Carajas, Lake Pata and marine deposits off the mouth of the Amazon River. All three records yield pollen histories of remarkable constancy and stability. By comparing them with deposits of equal antiquity from the cerrado (savanna) of central Brazil, we show that most of the Amazon lowlands remained under forest throughout a glacial cycle. This forest was never fragmented by open vegetation as postulated by the refugia hypothesis. Instead the intact forest of glacial times included significant populations of plants that are now montane, suggesting that the global warming of the early Holocene resulted in the expulsion of heat intolerant plants from the lowland forest. Pollen data from the Amazonian flank of the Andes and from Pacific Panama provide evidence that populations of these heat intolerant plants survive the heat of interglacials in part by maintaining large populations at cooler montane altitudes. Our conclusion that the Amazon lowlands were forested in glacial times specifically refutes the hypothesis of Amazonian glacial aridity. Accordingly we examine the geomorphological evidence for glacial aridity and find it wanting. Of the three paleodune systems reported for tropical South America, that of NE Brazil was active in the Holocene as well as the Pleistocene. Parts of NE Brazil were actually moister than now in late-glacial times. Paleodunes in the Pantanal have never been seen on the ground, and those in the Orinoco Llanos are undated and may bie of any age since the Tertiary. Arkosic sands in the Amazon fan deposits came from the Andean foothills or from down cutting by rivers and cannot be evidence of a former arid land surface. White sands of Amazonia formed as podzols, not by aeolian activity. Such Amazonian stone lines as have received critical scrutiny are concretionary pisolites in stratigraphic formations that are more than ten million years old. Although the Amazon was never arid, modeling cooler glacial tropics gives plausibility to a somewhat drier Amazon in glacial times, a concept given substance by pollen data for the movement of ecotones in Rondonia, by stream histories in the Bolivian Andes, and by evidence for lowered lake levels at Carajas and Lake Pata. But this reduced precipitation was never enough to fragment the forest in the Amazon lowlands themselves. Pleistocene mammals of the Napo river valley in Ecuador were able to live along the river system in a forested landscape. Our data suggest that the Amazon forests have been stable since the start of the Pleistocene, a fact that has contributed to the storage of vast diversity. The coming anthropogenic global warming and CO2 enrichment will add to the global warming already endured by Amazon biota in the Holocene. We think it possible that the expulsion from the lowland forests of heat intolerant species is already complete and that the forest property of maintaining its own microhabitat will allow the high species richness to survive more global warming, provided large enough tracts of forest are preserved. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Smithsonian Trop Res Inst, Balboa, Panama. Univ Sao Paulo, Inst Geosci, Dept Paleontol & Stratig DPE, BR-05422970 Sao Paulo, Brazil. Field Museum Nat Hist, Chicago, IL 60605 USA. Florida Inst Technol, Dept Biol Sci, Melbourne, FL 32901 USA. RP Marine Biol Lab, 7 MBL St, Woods Hole, MA 02543 USA. EM pcolinva@MBL.edu; pedeoliv@usp.br; mbush@fit.edu RI De Oliveira, Paulo/B-4559-2017; OI De Oliveira, Paulo/0000-0003-1040-4001; Bush, Mark/0000-0001-6894-8613 NR 131 TC 290 Z9 304 U1 6 U2 96 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0277-3791 J9 QUATERNARY SCI REV JI Quat. Sci. Rev. PD JAN PY 2000 VL 19 IS 1-5 BP 141 EP 169 DI 10.1016/S0277-3791(99)00059-1 PG 29 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 268PV UT WOS:000084425500011 ER PT S AU Matsushita, S Matsuo, H Sakamoto, A Pardo, JR AF Matsushita, S Matsuo, H Sakamoto, A Pardo, JR BE Butcher, HR TI FTS measurements of submillimeter opacity and other site testing at Pampa la Bola SO RADIO TELESCOPES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Radio Telescopes CY MAR 27-30, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc DE site testing; atmospheric opacity; submillimeter; water vapor; liquid water ID WAVE ATMOSPHERIC OPACITY; MODEL; WATER AB We have carried out Fourier Transform Spectrometer (FTS) measurements of the millimeter and submillimeter-wave (150 - 1500 GHz or 2 mm - 200 mu m) atmospheric opacity at Pampa la Bola, 4800 m above sea level in northern Chile on September 1997 and June 1998. One of the best transmission spectra show up to similar to 67% transmission at well-known submillimeter-wave windows. Supra-terahertz windows (located around 1035 GHz, 1350 GHz, and 1500 GHz) were identified in the same spectrum. The observed spectra can be well modeled by newly developed radiative-transfer calculations. Correlations between 220 GHz opacities and those of the center of submillimeter-wave windows or even those of the supra-terahertz windows were obtained using the entire the data set. Good correlations were obtained except for the periods affected by the liquid water opacity component. We succeeded to separate the total opacity in two parts: the water vapor opacity and the Liquid water opacity, using two frequencies, one in the millimeter domain and another one in the submillimeter. The separated water vapor opacity component skews good correlation with the 183 GHz pure mater vapor line opacity which is also covered in the measured spectra, but the liquid water opacity component shows no correlation. The liquid water opacity component also shows no correlation with the phase fluctuation measured with the 11 GHz radio seeing monitor. Modeling of this component is currently under way. Combined with a statistical study of the 225 GHz opacity data of the Chajnantor site (similar to 7 km apart from Pampa la Bola), it is estimated that submillimeter-wave observations can be done with zenith opacity less than 1.0 (at the most transparent frequency in those windows) for about 50% of the winter season, assuming no presence of liquid water absorption. C1 Harvard Smithsonian Ctr Astrophys, Submillimeter Array, Hilo, HI 96720 USA. RP Matsushita, S (reprint author), Harvard Smithsonian Ctr Astrophys, Submillimeter Array, 60 Keawe St,Suite 204, Hilo, HI 96720 USA. NR 22 TC 9 Z9 9 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3640-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4015 BP 378 EP 389 DI 10.1117/12.390432 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ70J UT WOS:000089219700039 ER PT S AU Stark, AA AF Stark, AA BE Butcher, HR TI Design considerations for large detector arrays on submillimeter-wave telescopes SO RADIO TELESCOPES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Radio Telescopes CY MAR 27-30, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc DE submillimeter; aberrations; field-of-view; detector arrays ID MICROWAVE BACKGROUND DECREMENT; EVOLUTION AB The emerging technology of large (similar to 10,000 pixel) submillimeter-wave bolometer arrays presents a novel optical design problem-how can such arrays be fed by diffraction-limited telescope optics where the primary mirror is less than 100,000 wavelengths in diameter? Standard Cassegrain designs for radiotelescope optics exhibit focal surface curvature so large that detectors cannot be placed more than 25 beam diameters from the central ray. The problem is worse for Ritchey-Chretien designs, because these minimize coma while increasing field curvature. Classical aberrations, including coma, are usually dominated by diffraction in submillimeter-wave single dish telescopes. The telescope designer must consider (1) diffraction, (2) aberration, (3) curvature of field, (4) cross-polarization, (5) internal reflections, (6) the effect of blockages, (7) means of beam chopping on- and off-source, (8) gravitational and thermal deformations of the primary mirror, (9) the physical mounting of large detector packages, and (10) the effect of gravity and (11) vibration on those detectors. Simultaneous optimization of these considerations in the case of large detector arrays leads to telescopes that differ considerably from standard radiotelescopy designs. Offset optics provide flexibility for mounting detectors, while eliminating blockage and internal reflections. Aberrations and cross-polarization can be the same as on-axis designs having the same diameter and focal length. Trade-offs include the complication of primary mirror homology and an increase in overall cost. A dramatic increase in usable field of view can be achieved using shaped optics. Solutions having one to six mirrors will be discussed, including a possible six-mirror design for the proposed South Pole 10m telescope. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Stark, AA (reprint author), Smithsonian Astrophys Observ, 60 Garden St,MS78, Cambridge, MA 02138 USA. NR 22 TC 6 Z9 6 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3640-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4015 BP 434 EP 445 DI 10.1117/12.390436 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ70J UT WOS:000089219700044 ER PT J AU Zhang, GM Tsou, YC Rosenberger, AL AF Zhang, Guangming Tsou, Yi-Chien Rosenberger, Alfred L. TI Reconstruction of the Homunculus skull using a combined scanning and stereolithography process SO RAPID PROTOTYPING JOURNAL LA English DT Article DE rapid prototyping; image processing; CAD; CAM; measurement AB The reconstructed skull of the primate fossil Homunculus, a Miocene New World monkey from Argentina, offers unique opportunities for further study and has revealed information that could not be observed or appreciated on the original damaged specimens. This paper presents the process that applies the rapid prototyping methodology to reconstruct and produce such a physical model of the Homunculus's skull. A laser scanner is used to digitize three pieces of sharp epoxy casts from the left facial skull and the mandible, which were broken apart during fossilization. Commercial software systems are used to develop image models of the fully reconstructed face and lower jaw. A stereolithography process is used to build the physical model. C1 [Zhang, Guangming; Tsou, Yi-Chien] Univ Maryland, Syst Res Inst, College Pk, MD 20742 USA. [Rosenberger, Alfred L.] Smithsonian Inst, Natl Zool Pk, Washington, DC 20008 USA. RP Zhang, GM (reprint author), Univ Maryland, Syst Res Inst, College Pk, MD 20742 USA. NR 16 TC 10 Z9 15 U1 2 U2 3 PU EMERALD GROUP PUBLISHING LIMITED PI BINGLEY PA HOWARD HOUSE, WAGON LANE, BINGLEY BD16 1WA, W YORKSHIRE, ENGLAND SN 1355-2546 J9 RAPID PROTOTYPING J JI Rapid Prototyping J. PY 2000 VL 6 IS 4 BP 267 EP 275 DI 10.1108/13552540010346542 PG 9 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA V50KL UT WOS:000203407100006 ER PT J AU Penfold, LM Wildt, DE Herzog, TL Lynch, W Ware, L Derrickson, SE Monfort, SL AF Penfold, LM Wildt, DE Herzog, TL Lynch, W Ware, L Derrickson, SE Monfort, SL TI Seasonal patterns of LH, testosterone and semen quality in the Northern pintail duck (Anas acuta) SO REPRODUCTION FERTILITY AND DEVELOPMENT LA English DT Article ID LUTEINIZING-HORMONE; PLATYRHYNCHOS; ANDROGENS; MALLARDS; CYCLE; BIRDS; BLOOD AB This study characterized seasonal changes in circulating LH and testosterone and in semen production and quality in the Northern pintail duck. Plasma LH and testosterone were measured in blood samples collected weekly throughout the year from eight males exposed to natural fluctuations in day length and temperature. Semen quality was evaluated weekly in these same males from April-June, the months when spermatozoa were produced. Semen quality (based on sperm concentration and normal morphology) peaked 0-2 weeks after sperm production onset and decreased sharply before sperm production cessation in late June. Nadir LH concentrations were measured in July and August with peak LH observed in May and November. There were clear seasonal patterns in circulating testosterone with July-September values being less (P<0.05) than October-December which, in turn, were less (P<0.05) than January-March. Maximal circulating testosterone (P<0.05) occurred during April-June, coincident with semen production. Weekly circulating LH during the breeding season was directly related to testosterone concentrations (P<0.01), but was not correlated to any specific semen or sperm trait (P>0.05). Testosterone concentrations throughout the breeding season were correlated (P<0.05) to total numbers of spermatozoa produced (volume x cell concentration) and percent normal sperm morphology. In summary, the Northern pintail experiences seasonal hormone fluctuations, with maximum circulating testosterone coinciding with peak ejaculate quality reflected by the production of high numbers of morphologically normal spermatozoa. C1 Smithsonian Inst, Conservat Res Ctr, Dept Reprod Sci, Front Royal, VA 22630 USA. RP Penfold, LM (reprint author), White Oak Conservat Ctr, 3823 Owens Rd, Yulee, FL 32097 USA. NR 38 TC 19 Z9 19 U1 1 U2 10 PU C S I R O PUBLISHING PI COLLINGWOOD PA 150 OXFORD ST, PO BOX 1139, COLLINGWOOD, VICTORIA 3066, AUSTRALIA SN 1031-3613 J9 REPROD FERT DEVELOP JI Reprod. Fertil. Dev. PY 2000 VL 12 IS 3-4 BP 229 EP 235 DI 10.1071/RD00093 PG 7 WC Developmental Biology; Reproductive Biology; Zoology SC Developmental Biology; Reproductive Biology; Zoology GA 412HW UT WOS:000167549800015 PM 11302434 ER PT J AU Davies, REG AF Davies, REG TI The birth of commercial aviation in the United State SO REVUE BELGE DE PHILOLOGIE ET D HISTOIRE LA English DT Article C1 Smithsonian Inst, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU REVUE BELGE PHILOLOGIE HISTOIR PI BRUSSELS PA RUE DE L ETOILE POLAIRE, 37, BRUSSELS, BELGIUM B-1080 USA SN 0035-0818 J9 REV BELGE PHILOL HIS JI Rev. Belg. Philol. Hist. PY 2000 VL 78 IS 3-4 BP 993 EP 1008 DI 10.3406/rbph.2000.4474 PG 16 WC History; Language & Linguistics; Literature SC History; Linguistics; Literature GA 614HJ UT WOS:000179182000011 ER PT J AU Ivanova, ES Hope, WD AF Ivanova, ES Hope, WD TI Two new species of Ungella Cobb, 1928 (Rhabditida : Drilonematoidea) from earthworms deposited in the Smithsonian Institution Natural History Museum SO RUSSIAN JOURNAL OF NEMATOLOGY LA English DT Article DE Drilonematoidea; earthworm parasites; Ungellidae; Ungella burmensis sp n.; U. mexicana sp n. AB Two new species of Ungella Cobb, 1928 are described from earthworms deposited in the collection of the Smithsonian Institution Natural History Museum. Ungella burmensis sp. n. is distinguished from U. secta Cobb, 1928 by having finely mammilated egg shells, smaller gubernaculum and more numerous pre-cloacal papillae. Ungella mexicana sp. n. differs from other species in the genus by having bifurcated spicule termini. The presence and absence of spicular apparatus within the ungellid genera is discussed. C1 Russian Acad Sci, Inst Parasitol, Moscow 117071, Russia. Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Ivanova, ES (reprint author), Russian Acad Sci, Inst Parasitol, Leninskii Prospect 33, Moscow 117071, Russia. NR 15 TC 5 Z9 5 U1 0 U2 0 PU MYLNEFIELD RESEARCH SERVICES PI DUNDEE PA INVERGOWRIE, DUNDEE DD2 5DA, SCOTLAND SN 0869-6918 J9 RUSS J NEMATOL JI Russ. J. Nematol. PY 2000 VL 8 IS 1 BP 57 EP 64 PG 8 WC Zoology SC Zoology GA 327PH UT WOS:000087801600005 ER PT J AU Mayo, EP AF Mayo, EP TI Party politics: The political impact of the first ladies' social role SO SOCIAL SCIENCE JOURNAL LA English DT Article AB All first ladies have entertained socially while in the White House. Indeed, the role is so much a part of the office that hosting is expected of the presidential spouses. This article considers the political impact of social hosting, a function that has often had significant consequences on the presidency and has allowed first ladies to influence political affairs. C1 Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. RP Mayo, EP (reprint author), 607 S St Asaph St, Alexandria, VA USA. NR 24 TC 5 Z9 5 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0362-3319 J9 SOC SCI J JI Soc. Sci. J. PY 2000 VL 37 IS 4 BP 577 EP 590 DI 10.1016/S0362-3319(00)00097-5 PG 14 WC Social Sciences, Interdisciplinary SC Social Sciences - Other Topics GA 385DA UT WOS:000165985600007 ER PT J AU Wood, JA AF Wood, JA TI Pressure and temperature profiles in the solar nebula SO SPACE SCIENCE REVIEWS LA English DT Review ID PROTOPLANETARY DISKS; EVOLUTION; SYSTEM AB Pressure and temperature profiles in several recent solar nebula models are reviewed. These parameters are important to cosmochemists because they determine the mineral assemblages that could form or exist in the nebula. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM jwood@cfa.harvard.edu NR 8 TC 19 Z9 19 U1 1 U2 5 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2000 VL 92 IS 1-2 BP 87 EP 93 DI 10.1023/A:1005249417716 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 357HP UT WOS:000089492700008 ER PT J AU Wood, JA AF Wood, JA TI The beginning: Swift and violent SO SPACE SCIENCE REVIEWS LA English DT Review ID PB SYSTEMATICS; SOLAR NEBULA; AGE AB Radiometric dating shows that the earliest steps in forming the substance of meteorites and assembling it into planetesimals occurred in a very short interval of time, 1-2 Ma. This study shows that rapid formation is also dictated by the need to use short-lived Al-26 (half-life T-1/2=0.74 Ma) as a heat source to metamorphose and in some cases melt the meteorite parent bodies after they accreted. The earliest events in solar system history dated by cosmochemists, formation at high temperatures of the Ca,Al-rich inclusions that occur in chondritic meteorites, probably occurred during the most energetic stage of protosolar disk evolution, as the protosun neared its present mass and infall drew to a close. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM jwood@cfa.harvard.edu NR 30 TC 5 Z9 5 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2000 VL 92 IS 1-2 BP 97 EP 112 DI 10.1023/A:1005207008031 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 357HP UT WOS:000089492700009 ER PT J AU Shang, H Shu, FH Lee, T Glassgold, AE AF Shang, H Shu, FH Lee, T Glassgold, AE TI Protostellar winds and chondritic meteorites - Formation of solids: The first step SO SPACE SCIENCE REVIEWS LA English DT Review DE X-wind; Young Stellar Objects; jets, chondrules; CAIs; extinct radioactivities ID MAGNETOCENTRIFUGALLY DRIVEN FLOWS; HERBIG-HARO OBJECTS; YOUNG STELLAR OBJECTS; T-TAURI STARS; MAGNETIC NEUTRON STARS; DOUBLE RADIO-SOURCES; MOLECULAR CLOUDS; VLA OBSERVATIONS; COSMIC-RAYS; JETS AB We discuss the interaction between the magnetosphere of a young star and its surrounding accretion disk. We consider how an X-wind can be driven magnetocentrifugally from the inner edge of the disk where accreting gas is diverted onto stellar field lines either to flow onto the Sun or to be flung outwards with the wind. The X-wind satisfies many observational tests concerning optical jets, Herbig-Haro objects, and molecular outflows. Connections may exist between primitive solar system materials and X-winds. Chondrules and calcium-aluminum-rich inclusions (CAIs) experienced short melting events uncharacteristic of the asteroid belt where meteorites originate. The inner edge of the solar nebula has the shortest orbital timescale available to the system, a few days. Protosolar flares introduce another timescale, tens of minutes to hours. CAIs may form when solids are lifted from shaded portions of the disk close to the Sun and are exposed to its intense light for a day or so before they are flung by the X-wind to much larger distances. Chondrules were melted, perhaps many times, by flares at larger distances from the Sun before being launched and annealed, but not remelted, in the X-wind. Aerodynamic sorting explains the narrow range of sizes with which CAIs and chondrules are found in chondritic meteorites. Flare-generated cosmic-rays may induce spallation reactions that produce some of the short-lived radioactivities associated with primitive solar system rocks. C1 Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Acad Sinica, Inst Earth Sci, Taipei 115, Taiwan. Acad Sinica, Inst Astron & Astrophys, Taipei 115, Taiwan. NYU, Dept Phys, New York, NY 10003 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS-42, Cambridge, MA 02138 USA. EM hshang@cfa.harvard.edu RI Lee, Typhoon/N-8347-2013 NR 67 TC 13 Z9 13 U1 1 U2 4 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PY 2000 VL 92 IS 1-2 BP 153 EP 176 DI 10.1023/A:1005234909848 PG 24 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 357HP UT WOS:000089492700013 ER PT B AU Dupree, AK AF Dupree, AK BE Pallavicini, R Micela, G Sciortino, S TI Chromospheres and activity in open cluster giants SO STELLAR CLUSTERS AND ASSOCIATIONS: CONVECTION, ROTATION, AND DYNAMOS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 2nd 3-Islands Euroconference on Stellar Clusters and Associations - Convection, Rotation, and Dynamos CY MAY 25-28, 1999 CL PALERMO, ITALY SP Observatorio Astron Palermo, European Union ID RED GIANTS; STARS; EVOLUTION; NGC-6940; SAMPLE AB Atmospheric dynamics, chromospheric radiative losses, heating requirements, and the evolution of chromospheric activity can be followed using the Ca II emission from giant stars in open clusters. Recent observations of giants in clusters and the field have been assembled for this review. M67 red giants in conjunction with giants in younger clusters create a continuous group of red giants in the color-magnitude diagram, with 0.1 less than or equal to (B - V) less than or equal to 1.65. Radiative losses, as measured by emission strengths from Ca II, decrease smoothly with decreasing stellar effective temperature in M67 and connect well to a combined sample of warmer cluster giants (NGC 6940, NGC 2477, IC 4756, and the Hyades) with M less than or equal to 3M(circle dot). A younger cluster, NGC 6940 displays chromospheric enhancements associated with binaries and X-ray sources. For these giants, the chromospheric losses appear dependent only on T-eff Although acoustic models for chromospheric heating apparently agree with the measured Ca II flux levels for the coolest giants, additional heating processes must be present in warmer giants and clump stars. Clump giants exhibit Ca II fluxes consistent with stars of similar colors on the red giant branch, suggesting a renaissance in chromospheric heating occurs after evolution beyond the red giant branch. Chromospheric heating in the giants of solar metallicity is Likely to be derived from multiple sources, both hydrodynamic causes as well as magnetically-related processes. The relative contribution of each heating mechanism changes with temperature in the stellar atmosphere, and these proportions appear to change during a star's evolution. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Dupree, AK (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 18 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-025-0 J9 ASTR SOC P PY 2000 VL 198 BP 411 EP 420 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ14A UT WOS:000087285100066 ER PT J AU Grissom, CA Charola, AE Wachowiak, MJ AF Grissom, CA Charola, AE Wachowiak, MJ TI Measuring surface roughness on stone: Back to basics SO STUDIES IN CONSERVATION LA English DT Article AB Styles profilometry, reflected-light image analysis and visual/tactile evaluation were tested as techniques for assessing roughness of abrasive-blasted stone. Measurement of microdrop water absorption time was also tested as a complementary technique. Instrumental techniques showed significant shortcomings when measuring surfaces of roughness similar to most weathered stone, as well as flame-finished surfaces comparable to tooled stone. Tactile comparison of surfaces was found to be a more practical and cost-effective technique. On historic masonry structures however, soiling and uneven weathering limit the usefulness of roughness as a property to be measured in evaluating cleaning techniques. C1 Smithsonian Inst, Museum Support Ctr, Washington, DC 20560 USA. RP Grissom, CA (reprint author), Smithsonian Inst, Museum Support Ctr, SCMRE MRC 534, Washington, DC 20560 USA. NR 26 TC 14 Z9 14 U1 0 U2 4 PU MANEY PUBLISHING PI LEEDS PA STE 1C, JOSEPHS WELL, HANOVER WALK, LEEDS LS3 1AB, W YORKS, ENGLAND SN 0039-3630 EI 2047-0584 J9 STUD CONSERV JI Stud. Conserv. PY 2000 VL 45 IS 2 BP 73 EP 84 DI 10.2307/1506665 PG 12 WC Archaeology; Art; Chemistry, Applied; Chemistry, Analytical; Spectroscopy SC Archaeology; Art; Chemistry; Spectroscopy GA 332EN UT WOS:000088061400001 ER PT J AU Basset, Y AF Basset, Y TI Insect herbivores foraging on seedlings in an unlogged rain forest in Guyana: spatial and temporal considerations SO STUDIES ON NEOTROPICAL FAUNA AND ENVIRONMENT LA English DT Article DE insect herbivores; seedlings; host specificity; spatial distribution; rain forest; seasonality; Guyana ID TROPICAL INSECTS; ABUNDANCE; SEASONALITY; ARTHROPODS; DIVERSITY; TREE; PHENOLOGY AB About 9,000 individuals of sap-sucking and leaf-chewing insects, representing 345 species, were collected from 10,000 seedlings belonging to 5 rainforest tree species in an unlogged forest in Guyana. For the 40 most common species, it was possible to estimate their host specificity, diurnal activity, seasonal distribution, spatial aggregation, abundance and body weight. Most species were generalists but more specialised species tended to show a higher spatial aggregation, a more restricted diurnal activity and a higher seasonality. Although insect abundance was highest at the onset of the long wet season in May, seasonal amplitude was not pronounced. The combined effects of host and rainfall explained 14.5% of the total variance in insect seasonality, which was poorly explained by the leaf production of seedlings. The spatial distribution of insects was often aggregated and, overall, explained by host effect, production of young foliage, number of conspecific trees within a radius of 50m, and number of dead seedlings at each collecting station. However, these variables explained only 7% of the variance in spatial distribution. The lack of notable influence of leaf production and other important variables recorded at the collecting stations suggests that the seedlings represent a marginal food resource for most of the insect species collected. C1 CABI Biosci Environm, Ascot, Berks, England. RP Basset, Y (reprint author), Smithsonian Trop Res Inst, Apartado 2072, Balboa, Ancon, Panama. RI Basset, Yves/B-6642-2014 NR 34 TC 12 Z9 12 U1 0 U2 1 PU SWETS ZEITLINGER PUBLISHERS PI LISSE PA P O BOX 825, 2160 SZ LISSE, NETHERLANDS SN 0165-0521 J9 STUD NEOTROP FAUNA E JI Stud. Neotrop. Fauna Environ. PY 2000 VL 35 IS 2 BP 115 EP 129 DI 10.1076/0165-0521(200008)35:2;1-9;FT115 PG 15 WC Zoology SC Zoology GA 340RZ UT WOS:000088549900006 ER PT S AU Walsworth, RL Bear, D Humphrey, M Mattison, EM Phillips, DF Stoner, RE Vessot, RFC AF Walsworth, RL Bear, D Humphrey, M Mattison, EM Phillips, DF Stoner, RE Vessot, RFC BE Guo, XH Thomas, AW Williams, AG TI New clock comparison searches for Lorentz and CPT violation SO SYMMETRIES IN SUBATOMIC PHYSICS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 3rd International Symposium on Symmetries in Subatomic Physics (SYMM 2000) CY MAR 13-17, 2000 CL ADELAIDE, AUSTRALIA SP IUPAP, Ctr Subatom Struct Matter, Natl Inst Theoret Phys ID HIGHER-DIMENSIONAL THEORIES; NOBLE-GAS MASER; FREQUENCY-SHIFTS; STANDARD MODEL; HYDROGEN MASER; TESTING CPT; STRINGS; INVARIANCE; SYSTEM; ELECTRODYNAMICS AB We present two new measurements constraining Lorentz and CPT violation using the Xe-129/He-3 Zeeman maser and atomic hydrogen masers. Experimental investigations of Lorentz and CPT symmetry provide important tests of the framework of the standard model of particle physics and theories of gravity. The two-species Xe-129/He-3 Zeeman maser bounds violations of CPT and Lorentz symmetry of the neutron at the 10(-31) GeV level. Measurements with atomic hydrogen masers provide a clean limit of CPT and Lorentz; symmetry violation of the proton at the 10(-27) GeV level. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Walsworth, RL (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 50 TC 5 Z9 5 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-964-5 J9 AIP CONF PROC PY 2000 VL 539 BP 119 EP 129 PG 11 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BR18K UT WOS:000165808700015 ER PT B AU Wolk, SJ Walter, FM AF Wolk, SJ Walter, FM BE Rebolo, R ZapateroOsorio, MR TI Very low mass stars and brown dwarfs in the belt of Orion SO VERY LOW-MASS STARS AND BROWN DWARFS SE CAMBRIDGE CONTEMPORARY ASTROPHYSICS LA English DT Proceedings Paper CT 1st Three Island Euroconference on Stellar Clusters and Associations CY MAY 11-15, 1998 CL LAS PALMAS GC, SPAIN SP European Union, Inst Astrofis Canarias, Cabildo La Palma ID SPECTRAL SEQUENCE; MODEL AB As part of our ongoing research into low-mass star formation in Orion, we have obtained deep photometric and spectroscopic observations of PMS objects in the sigma Orionis cluster and near the other O stars in the belt of Orion. The photometry indicates the existence of objects with masses as low as 0.01 M-. (100 M-jup). Spectroscopic follow-up has confirmed the sub-stellar nature of the candidate object tested. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Wolk, SJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 17 TC 3 Z9 3 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI CAMBRIDGE PA THE PITT BUILDING, TRUMPINGTON ST, CAMBRIDGE CB2 1RP, CAMBS, ENGLAND BN 0-521-66335-0 J9 CAM CONTEMP ASTROPHY PY 2000 BP 38 EP 45 DI 10.1017/CBO9780511564758.005 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BS92V UT WOS:000171426500004 ER PT B AU Luhman, KL AF Luhman, KL BE Rebolo, R ZapateroOsorio, MR TI Brown dwarfs and the low-mass initial mass function in young clusters SO VERY LOW-MASS STARS AND BROWN DWARFS SE CAMBRIDGE CONTEMPORARY ASTROPHYSICS LA English DT Proceedings Paper CT 1st Three Island Euroconference on Stellar Clusters and Associations CY MAY 11-15, 1998 CL LAS PALMAS GC, SPAIN SP European Union, Inst Astrofis Canarias, Cabildo La Palma ID RHO-OPHIUCHI CLUSTER; SPECTROSCOPY; PLEIADES; SEQUENCE; L1495E; STAR AB We have conducted an extensive program of optical and IR imaging and spectroscopy targeted at the low-mass populations of nearby (less than or equal to 300 pc) young (similar to 1-10 Myr old) clusters: L1495E, IC 348, and rho Oph. By combining the spectroscopic data with IR luminosity function modeling, we arrive at mass functions which are roughly fiat or slowly declining in logarithmic mass units below similar to0.4 M-. into the substellar regime. With the discovery of several likely brown dwarfs, we demonstrate the potential of young clusters in studying the formation and mass functions of substellar objects. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02140 USA. RP Luhman, KL (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02140 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI CAMBRIDGE PA THE PITT BUILDING, TRUMPINGTON ST, CAMBRIDGE CB2 1RP, CAMBS, ENGLAND BN 0-521-66335-0 J9 CAM CONTEMP ASTROPHY PY 2000 BP 68 EP 74 DI 10.1017/CBO9780511564758.008 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BS92V UT WOS:000171426500007 ER PT S AU Murray, SS Chappell, J Kenter, A Juda, M Kraft, R Zombeck, M Meehan, G Austin, G Gomes, J AF Murray, SS Chappell, J Kenter, A Juda, M Kraft, R Zombeck, M Meehan, G Austin, G Gomes, J BE Flanagan, KA Siegmund, OHW TI Event screening for the Chandra X-ray Observatory High Resolution Camera (HRC) SO X-RAY AND GAMMA-RAY INSTRUMENTATION FOR ASTRONOMY XI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray and Gamma-Ray Instrumentation for Astronomy IX CY AUG 02-04, 2000 CL SAN DIEGO, CA SP SPIE DE X-ray detector; MCP; digital processing ID AXAF AB The Chandra X-ray Observatory High Resolution Camera is an improved version of similar Microchannel Plate (MCP) based detectors that were previously used on the Einstein and ROSAT X-ray observatories. The HRC consists of two detectors in a common housing, and sharing some processing electronics. Only one detector operates at a time. The HRC-I is a 100mm x 100mm device that is used for wide field of view imaging with sub-arcsecond angular resolution. The HRC-S is a 300mm x 30mm device that is used to readout the Low Energy Transmission Grating Spectrometer (LETGS) providing very high spectral resolution. The main differences from previous missions are the larger format MCP's, radioisotope free MCP glass, and an active Cosmic Ray anti-coincidence shield. Event processing in the HRC is limited to digitizing selected signals from the readout device and transmitting these to the ground. As a result, it is possible to examine and screen the data during processing. Algorithms have been developed to identify non-X-ray events thereby reducing the detector background. Event screening can also detect and filter out "bad" events that might otherwise degrade image quality. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Murray, SS (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 14 TC 8 Z9 8 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3785-9 J9 P SOC PHOTO-OPT INS PY 2000 VL 4140 BP 144 EP 154 DI 10.1117/12.409108 PG 11 WC Astronomy & Astrophysics; Instruments & Instrumentation SC Astronomy & Astrophysics; Instruments & Instrumentation GA BR53H UT WOS:000166723400014 ER PT S AU Juda, M Austin, GK Chappell, JH Gomes, JJ Kenter, AT Kraft, RP Murray, SS Zombeck, MV AF Juda, M Austin, GK Chappell, JH Gomes, JJ Kenter, AT Kraft, RP Murray, SS Zombeck, MV BE Flanagan, KA Siegmund, OHW TI Improving Chandra High Resolution Camera event positions via corrections to crossed-grid charge detector signals SO X-RAY AND GAMMA-RAY INSTRUMENTATION FOR ASTRONOMY XI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray and Gamma-Ray Instrumentation for Astronomy IX CY AUG 02-04, 2000 CL SAN DIEGO, CA SP SPIE DE X-ray detectors; microchannel plates; crossed-grid charge detector; High Resolution Camera; Chandra X-ray Observatory ID AXAF; SPECTROMETER; CALIBRATION AB The High Resolution Camera (HRC) on-board the Chandra X-ray Observatory (CXO) provides the highest resolution X-ray images of celestial sources ever taken. Unfortunately, ringing in the electronics compromises the position readout signals for some of the events. The compromised signals affect the angular resolution that can be achieved. We present an empirically derived algorithm that can be used in ground processing of the data to minimize the impact of the ringing on the calculated event positions. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Juda, M (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 14 TC 3 Z9 3 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3785-9 J9 P SOC PHOTO-OPT INS PY 2000 VL 4140 BP 155 EP 165 DI 10.1117/12.409109 PG 11 WC Astronomy & Astrophysics; Instruments & Instrumentation SC Astronomy & Astrophysics; Instruments & Instrumentation GA BR53H UT WOS:000166723400015 ER PT S AU Bloser, PF Narita, T Jenkins, JA Grindlay, JE AF Bloser, PF Narita, T Jenkins, JA Grindlay, JE BE Flanagan, KA Siegmund, OHW TI Construction and testing of a pixellated CZT detector and shield for a hard X-ray astronomy balloon flight SO X-RAY AND GAMMA-RAY INSTRUMENTATION FOR ASTRONOMY XI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray and Gamma-Ray Instrumentation for Astronomy IX CY AUG 02-04, 2000 CL SAN DIEGO, CA SP SPIE DE CZT; background; shielding; balloon flights; hard X-ray astronomy; instrumentation ID CDZNTE DETECTORS; CDTE; ALTITUDES AB We report on the construction and laboratory testing of pixellated CZT detectors mounted in a flip-chip, tiled fashion and read out by an ASIC, as required for proposed hard X-ray astronomy missions. Two 10 mm x 10 mm x 5 mm detectors were fabricated, one out of standard eV Products high-pressure Bridgman CZT and one out of IMARAD horizontal Bridgman CZT. Each was fashioned with a 4 x 4 array of gold pixels on a 2.5 mm pitch with a surrounding guard ring. The detectors were mounted side by side on a carrier card, such that the pixel pitch was preserved, and read out by a 32-channel VA-T,4 ASIC from IDE AS Corp. controlled by a PC/104 single-board computer. A passive shield/collimator surrounded by plastic scintillator encloses the detectors on five sides and provides a similar to 40 degrees field of view. Thus this experiment tests key techniques required for future hard X-ray survey instruments. The experiment was taken to Ft Sumner, NM in May 2000 in preparation for a scientific balloon flight aboard the joint Harvard-MSFC EXITE2/HERO payload. Although we did not receive a flight opportunity, and are currently scheduled to May in September 2000, we present our calibration data in the flight configuration together with data analysis techniques and simulations of the expected flight background spectrum. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Bloser, PF (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 21 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3785-9 J9 P SOC PHOTO-OPT INS PY 2000 VL 4140 BP 237 EP 248 DI 10.1117/12.409116 PG 12 WC Astronomy & Astrophysics; Instruments & Instrumentation SC Astronomy & Astrophysics; Instruments & Instrumentation GA BR53H UT WOS:000166723400023 ER PT S AU Silver, E Bandler, S Schnopper, H Murray, S Barbera, M Madden, N Landis, D Beeman, J Haller, EE AF Silver, E Bandler, S Schnopper, H Murray, S Barbera, M Madden, N Landis, D Beeman, J Haller, EE BE Flanagan, KA Siegmund, OHW TI NTD germanium-based microcalorimeters for hard x-ray spectroscopy SO X-RAY AND GAMMA-RAY INSTRUMENTATION FOR ASTRONOMY XI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray and Gamma-Ray Instrumentation for Astronomy IX CY AUG 02-04, 2000 CL SAN DIEGO, CA SP SPIE DE hard x-rays; cryogenic detectors; spectroscopy ID DESIGN AB Composite microcalorimeters using neutron transmutation-doped germanium (NTD) thermistors have been tested at hard x-ray energies. We present a broad band spectrum showing the energy resolution at 60 keV to be similar to 50 eV. The application of these microcalorimeters to the field of nuclear line astrophysics is discussed. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Silver, E (reprint author), Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RI Bandler, Simon/A-6258-2010; OI Bandler, Simon/0000-0002-5112-8106; Barbera, Marco/0000-0002-3188-7420 NR 10 TC 12 Z9 12 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3785-9 J9 P SOC PHOTO-OPT INS PY 2000 VL 4140 BP 397 EP 401 DI 10.1117/12.409135 PG 5 WC Astronomy & Astrophysics; Instruments & Instrumentation SC Astronomy & Astrophysics; Instruments & Instrumentation GA BR53H UT WOS:000166723400039 ER PT S AU Jerius, D Donnelly, RH Tibbetts, MS Edgar, RJ Gaetz, TJ Schwartz, DA Van Speybroeck, LP Zhao, P AF Jerius, D Donnelly, RH Tibbetts, MS Edgar, RJ Gaetz, TJ Schwartz, DA Van Speybroeck, LP Zhao, P BE Trumper, JE Aschenbach, B TI Orbital measurement and verification of the Chandra X-Ray Observatory's PSF SO X-RAY OPTICS, INSTRUMENTS, AND MISSIONS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray Optics, Instruments, and Missions III CY MAR 27-29, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc DE X-ray optics; PSF; Chandra X-ray Observatory; CXO ID AXAF AB The recently launched Chandra X-Ray Observatory (CXO) was designed to have the sharpest angular resolution yet of any X-ray telescope. Detailed modeling and metrology of the optics followed by extensive testing at the X-Ray Calibration Facility at the Marshall Space Flight Center in Huntsville, Alabama indicated that the optics were performing exceedingly well. While our analysis accounted for distortion of the mirrors due to gravity and the effects of finite distance and size of the X-ray generator, it was only on-orbit that we expected to directly observe the specified half are-second performance. We present here results of the on-orbit calibration of the point spread function (PSF), comparing it with our predictions. We discuss how the PSF varies with source location in the telescope field of view, as well as with the spectral energy distribution of the source. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Jerius, D (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 11 TC 30 Z9 30 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3637-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4012 BP 17 EP 27 DI 10.1117/12.391555 PG 11 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BQ70G UT WOS:000089219400002 ER PT S AU Schwartz, DA David, LP Donnelly, RH Edgar, RJ Gaetz, TJ Graessle, DE Jerius, D Juda, M Kellogg, EM McNamara, BR Plucinsky, PP VanSpeybroeck, LP Wargelin, B Wolk, S Zhao, P Dewey, D Marshall, HL Schulz, NS Elsner, R Kolodziejczak, J O'Dell, SL Swartz, DA Tennant, A Weisskopf, MC AF Schwartz, DA David, LP Donnelly, RH Edgar, RJ Gaetz, TJ Graessle, DE Jerius, D Juda, M Kellogg, EM McNamara, BR Plucinsky, PP VanSpeybroeck, LP Wargelin, B Wolk, S Zhao, P Dewey, D Marshall, HL Schulz, NS Elsner, R Kolodziejczak, J O'Dell, SL Swartz, DA Tennant, A Weisskopf, MC BE Trumper, JE Aschenbach, B TI The absolute effective area of the Chandra high resolution mirror assembly (HRMA) SO X-RAY OPTICS, INSTRUMENTS, AND MISSIONS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray Optics, Instruments, and Missions III CY MAR 27-29, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc DE Chandra observatory; X-ray astronomy; X-ray telescopes; calibration ID OPTICAL-CONSTANTS; AXAF; CALIBRATIONS; SCATTERING; REFLECTION AB The Chandra X-ray Observatory was launched in July 1999, and is returning exquisite sub-are second X-ray images of star groups, supernova remnants, galaxies, quasars, and clusters of galaxies. In addition to being the premier,X-ray observatory in terms of angular and spectral resolution, Chandra is the best calibrated X-ray facility ever flown. We discuss here the calibration of the on-axis effective area of the High Resolution Mirror Assembly. Because we do not know the absolute X-ray flux density of any celestial source, this must be based primarily on ground measurements and on modeling. We use celestial sources which may be assumed to have smoothly varying spectra, such as the the BL Lac object Markarian 421, to verify the continuity of the area calibration as a function of energy across the Ir M-edges. We believe the accuracy of the HRMA area calibration is of order 2%. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Schwartz, DA (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 18 TC 22 Z9 22 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3637-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4012 BP 28 EP 40 DI 10.1117/12.391566 PG 13 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BQ70G UT WOS:000089219400003 ER PT S AU Gaetz, TJ Jerius, D Edgar, RJ Van Speybroeck, L Schwartz, DA Markevitch, ML Taylor, SC Schulz, NS AF Gaetz, TJ Jerius, D Edgar, RJ Van Speybroeck, L Schwartz, DA Markevitch, ML Taylor, SC Schulz, NS BE Trumper, JE Aschenbach, B TI Orbital verification of the CXO High Resolution Mirror Assembly alignment and vignetting SO X-RAY OPTICS, INSTRUMENTS, AND MISSIONS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray Optics, Instruments, and Missions III CY MAR 27-29, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc DE X-ray optics; alignment; vignetting; Chandra; CXO ID AXAF AB Prior to launch, the High Resolution Mirror Assembly (HRMA) of the Chandra X-ray Observatory underwent extensive ground testing at the X-ray Calibration Facility (XRCF) at the Marshall Space Flight Center in Huntsville, Alabama. The resulting data were used to validate a high fidelity raytrace model for the HRMA performance. Further observations made during the post-launch Orbital Activation and Calibration period allow the on-orbit condition of the X-ray optics to be assessed. Based on these ground-based and on-orbit data, we examine the alignment of the X-ray optics based on the off-axis point spread function. We discuss how single-reflection ghost data obtained at XRCF can be used to better constrain the HRMA optical axis data. We examine the vignetting and the single-reflection ghost suppression properties of the telescope. Slight imperfections in alignment lead to a small azimuthal dependence of the off-axis effective area; the morphology of off-axis images also shows an additional small azimuthal dependence varying as 1/2 the position angle. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Gaetz, TJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3637-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4012 BP 41 EP 52 DI 10.1117/12.391574 PG 12 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BQ70G UT WOS:000089219400004 ER PT S AU Murray, SS Austin, G Chappell, J Gomes, J Kenter, A Kraft, R Meehan, G Zombeck, M Fraser, G Serio, S AF Murray, SS Austin, G Chappell, J Gomes, J Kenter, A Kraft, R Meehan, G Zombeck, M Fraser, G Serio, S BE Trumper, JE Aschenbach, B TI In-flight performance of the Chandra High Resolution Camera SO X-RAY OPTICS, INSTRUMENTS, AND MISSIONS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray Optics, Instruments, and Missions III CY MAR 27-29, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc AB The High Resolution Camera (HRC) is one of the two focal plane instruments on NASA's Chandra X-ray Observatory which was successfully launched July 23, 1999. The Chandra Observatory will perform high resolution spectroscopy and imaging in the X-ray band of 0.1 to 10 keV. The HRC instrument consists of two detectors, the HRC-I for imaging and the HRC-S for spectroscopy. In this paper we present an overview of the in-flight performance of the High Resolution Camera and discuss some of the initial scientific results. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Murray, SS (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 13 TC 40 Z9 40 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3637-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4012 BP 68 EP 80 DI 10.1117/12.391591 PG 13 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BQ70G UT WOS:000089219400006 ER PT S AU Kenter, A Chappell, JH Kraft, R Meehan, G Murray, SS Zombeck, M Hole, KT Juda, M Donnelly, RH Patnaude, D Pease, D Wilton, C Zhao, P Austin, G Fraser, G Pearson, J Lees, J Brunton, A Barbera, M Collura, A Serio, S AF Kenter, A Chappell, JH Kraft, R Meehan, G Murray, SS Zombeck, M Hole, KT Juda, M Donnelly, RH Patnaude, D Pease, D Wilton, C Zhao, P Austin, G Fraser, G Pearson, J Lees, J Brunton, A Barbera, M Collura, A Serio, S BE Trumper, JE Aschenbach, B TI In-flight performance and calibration of the Chandra high resolution camera imager (HRC-I) SO X-RAY OPTICS, INSTRUMENTS, AND MISSIONS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray Optics, Instruments, and Missions III CY MAR 27-29, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc DE Chandra; AXAF; high resolution camera ID RAY AB The High Resolution Camera (HRC) is one of the two focal plane instruments on the NASA Chandra X-ray Observatory (CXO) which was successfully launched on July 23, 1999. The CXO performs high resolution spectroscopy and imaging in the X-ray band of 0.07 to 10 keV. The HRC instrument consists of two detectors, HRC-I for imaging and HRC-S for spectroscopy. The other focal plane instrument is the Chandra CCD Imaging Spectrometer (AGIS). Each HRC detector consists of a thin aluminized polyimide window, a chevron pair of microchannel plates (MCPs) and a crossed grid charge readout. The HRC-I is an similar to 100 x 100 mm detector optimized for high resolution imaging and timing, the HRC-S is an similar to 20 x 300 mm detector optimized to function as the readout for the Low Energy Transmission Grating (LETG). In this paper we present and compare flight results with the latest results of the ground calibration for the HRC-I detector. In particular we will compare ground and in flight data on detector background, effective area, quantum efficiency and point spread response function. The development of the HRC is a collaborative effort between The Smithsonian Astrophysical Observatory, University of Leicester UK and the Osservatorio Astronomico, G.S. Vaiana, Palermo Italy. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Kenter, A (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 28 TC 11 Z9 11 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3637-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4012 BP 467 EP 492 DI 10.1117/12.391585 PG 26 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BQ70G UT WOS:000089219400046 ER PT S AU Kraft, RP Chappell, JH Kenter, AT Meehan, GR Murray, SS Zombeck, MV Donnelly, RH Drake, JJ Johnson, CO Juda, M Patnaude, D Pease, DO Ratzlaff, PW Wargelin, BJ Zhao, P Austin, GK Fraser, GW Pearson, JF Lees, JE Brunton, AN Barbera, M Collura, A Serio, S AF Kraft, RP Chappell, JH Kenter, AT Meehan, GR Murray, SS Zombeck, MV Donnelly, RH Drake, JJ Johnson, CO Juda, M Patnaude, D Pease, DO Ratzlaff, PW Wargelin, BJ Zhao, P Austin, GK Fraser, GW Pearson, JF Lees, JE Brunton, AN Barbera, M Collura, A Serio, S BE Trumper, JE Aschenbach, B TI In-flight performance and calibration of the Chandra high resolution camera spectroscopic readout (HRC-S) SO X-RAY OPTICS, INSTRUMENTS, AND MISSIONS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray Optics, Instruments, and Missions III CY MAR 27-29, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc DE x-ray imaging; x-ray spectroscopy; Chandra; AXAF; HRC; High Resolution Camera AB The High Resolution Camera (HRC) is one of two focal plane instruments on the NASA Chandra X-ray Observatory (CXO) which was successfully launched on July 23, 1999. The Chandra X-ray Observatory was designed to perform high resolution spectroscopy and imaging in the X-ray band of 0.07 to 10 keV. The HRC instrument consists of two detectors, HRC-I for imaging and HRC-S for spectroscopy. Each HRC detector consists of a thin aluminized polyimide blocking filter, a chevron pair of microchannel plates (MCPs) and a crossed grid charge readout. The HRC-I is an similar to 100 x 100 mm detector optimized for high resolution imaging and timing, the HRC-S is an similar to 20 x 300 mm detector optimized to function as the readout for the Low Energy Transmission Grating (LETG). In this paper we discuss the in-flight performance of the HRC-S, and present preliminary analysis of flight calibration data and compare it with the results of the ground calibration and pre-flight predictions. In particular we will compare ground data and in-flight data on detector background, quantum efficiency, spatial resolution, pulse height resolution, and point spread response function. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Kraft, RP (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS-31, Cambridge, MA 02138 USA. NR 32 TC 3 Z9 3 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3637-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4012 BP 493 EP 517 DI 10.1117/12.391586 PG 25 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BQ70G UT WOS:000089219400047 ER PT S AU Aldcroft, TL Karovska, M Cresitello-Dittmar, ML Cameron, RA Markevitch, ML AF Aldcroft, TL Karovska, M Cresitello-Dittmar, ML Cameron, RA Markevitch, ML BE Trumper, JE Aschenbach, B TI Initial performance of the aspect system on the Chandra Observatory: Post-facto aspect reconstruction SO X-RAY OPTICS, INSTRUMENTS, AND MISSIONS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray Optics, Instruments, and Missions III CY MAR 27-29, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc DE Chandra; aspect; X-ray telescope AB The aspect system of the Chandra Observatory plays a key role in realizing the full potential of Chandra's X-ray optics and detectors. To achieve the highest spatial and spectral resolution (for grating observations), an accurate post-facto time history of the spacecraft attitude and internal alignment is needed. The CXC has developed a suite of tools which process sensor data from the aspect camera assembly and gyroscopes, and produce the spacecraft aspect solution. In this poster, the design of the aspect pipeline software is briefly described, followed by details of aspect system performance during the first eight months of flight. The two key metrics of aspect performance are: image reconstruction accuracy, which measures the X-ray image blurring introduced by aspect; and celestial location, which is the accuracy of detected source positions in absolute sky coordinates. C1 Smithsonian Astrophys Observ, Cambridge, MA USA. RP Aldcroft, TL (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA USA. NR 2 TC 45 Z9 45 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3637-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4012 BP 650 EP 657 DI 10.1117/12.391604 PG 8 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BQ70G UT WOS:000089219400063 ER PT S AU Cameron, RA Aldcroft, TL Podgorski, WA Freeman, MD Shirer, JJ AF Cameron, RA Aldcroft, TL Podgorski, WA Freeman, MD Shirer, JJ BE Trumper, JE Aschenbach, B TI Initial performance of the attitude control and aspect determination sub-systems on the Chandra Observatory SO X-RAY OPTICS, INSTRUMENTS, AND MISSIONS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray Optics, Instruments, and Missions III CY MAR 27-29, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc DE aspect; Chandra; spacecraft; optics AB The pointing control and aspect determination (PCAD) subsystem of the Chandra X-ray Observatory plays a key role in realizing the full potential of Chandra's X-ray optics and detectors. We review the performance of the spacecraft hardware components and sub-systems, which provide information for both real time control of the attitude and attitude stability of the Chandra Observatory and also for more accurate post-facto attitude reconstruction. These flight components are comprised of the aspect camera (star tracker) and inertial reference units (gyros), plus the fiducial lights and fiducial transfer optics which provide an alignment null reference system for the science instruments and X-ray optics, together with associated thermal and structural components. Key performance measures will be presented for aspect camera focal plane data, gyro performance both during stable pointing and during maneuvers, alignment stability and mechanism repeatability. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Cameron, RA (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 3 TC 3 Z9 3 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3637-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4012 BP 658 EP 668 DI 10.1117/12.391605 PG 11 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BQ70G UT WOS:000089219400064 ER PT S AU Virani, SN Muller-Mellin, R Plucinsky, PP Butt, YM AF Virani, SN Muller-Mellin, R Plucinsky, PP Butt, YM BE Trumper, JE Aschenbach, B TI The Chandra X-ray Observatory's radiation environment and the AP-8/AE-8 model SO X-RAY OPTICS, INSTRUMENTS, AND MISSIONS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray Optics, Instruments, and Missions III CY MAR 27-29, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc DE Chandra; space missions; radiation environment; radiation belts; radiation models; radiation damage; magnetosphere ID AXAF AB The Chandra X-ray Observatory (CXO) was launched on July 23, 1999 and reached its final orbit on August 7, 1999. The CXO is in a highly elliptical orbit, approximately 140,000 km x 10,000 km, and has a period of approximately 63.5 hours (approximate to 2.65 days). It transits the Earth's Van Alien belts once per orbit during which no science observations can be performed due to the high radiation environment. The Chandra X-ray Observatory Center (CXC) currently uses the National Space Science Data Center's "near Earth" AP-8/AE-8 radiation belt model to predict the start and end times of passage through the radiation belts. However, our scheduling software uses only a simple dipole model of the Earth's magnetic field. The resulting B, L magnetic coordinates, do not always give sufficiently accurate predictions of the start and end times of transit of the Van Alien belts. We show this by comparing to the data from Chandra's on-board radiation monitor, the EPHIN (Electron, Proton, Helium Instrument particle detector) instrument. We present evidence that demonstrates this mis-timing of the outer electron radiation belt as well as data that also demonstrate the significant variablity of one radiation belt transit to the next as experienced by the CXO, We also present an explanation for why the dipole implementation of the AP-8/AE-8 model is not ideally suited for the CXO. Lastly, we provide a brief discussion of our on-going efforts to identify a model that accounts for radiation belt variability, geometry, and one that can be used for observation scheduling purposes. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Virani, SN (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 20 TC 6 Z9 6 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3637-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4012 BP 669 EP 680 DI 10.1117/12.391606 PG 12 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BQ70G UT WOS:000089219400065 ER PT S AU Plucinsky, PP Virani, SN AF Plucinsky, PP Virani, SN BE Trumper, JE Aschenbach, B TI The observed on-orbit background of the ACIS instrument on the Chandra X-ray Observatory SO X-RAY OPTICS, INSTRUMENTS, AND MISSIONS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray Optics, Instruments, and Missions III CY MAR 27-29, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc DE Chandra; space missions; CCDs; radiation environment; radiation belts; radiation models; radiation damage; magnetosphere AB We have analyzed data acquired during the Orbital Activation and Checkout (OAC) and Guest Observer (GO) phases of the Chandra X-ray Observatory (CXO) mission in order to characterize the background of the Advanced CCD Imaging Spectrometer (ACIS) instrument produced by energetic particles. The ACIS instrument contains 8 Front-Illuminated (FI) CCDs and 2 Back-Illuminated (BI) CCDs. The Fl and BI CCDs exhibit dramatically different responses to enhancements in the particle flux. The FI CCDs show relatively little increase in the overall count rate, typical increases are 1 - 5 cts s(-1) above the quiescent level; the BI CCDs can show large excursions to as high as 100 cts s(-1) above the quiescent level. The durations of these intervals of enhanced background are also highly variable ranging from 500 s to 10(4) s. These periods of enhanced background are sometimes but not always associated with increased particle flux when Chandra is near the radiation belts. We see evidence for a weak correlation with the low-energy electron channel of the. Electron, Proton, Helium Instrument particle detector (EPHIN) instrument on-board Chandra. We present some of the most extreme examples of these background enhancements identified to this point in the mission. The spatial distribution of these enhanced background events is more intense in the middle of the detectors and fainter towards the top and bottom, inconsistent with what one would expect for the vignetting pattern of the telescope and more consistent with an isotropic illumination. The spectral distribution isa continuum across the entire bandpass from 0.3 to 10.0 keV and can not be characterized by a simple power-law plus constant model. The two BI CCDs on Chandra respond similarly to these enhanced background rates, offering the possibility of using data from the off-axis BI CCD to understand the background of the on-axis BI CCD. The traditional techniques of distinguishing background events from x-ray events are ineffective in excluding these background events. Therefore, we suggest that observers might want to consider more aggressive on-board event filtering to reduce the contribution of these background events to the finite ACIS telemetry limit. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Plucinsky, PP (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 5 TC 8 Z9 8 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3637-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4012 BP 681 EP 692 DI 10.1117/12.391607 PG 12 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BQ70G UT WOS:000089219400066 ER PT S AU Pease, D Drake, JJ Johnson, CO Kashyap, V Kraft, RP Ratzlaff, PW Wargelin, BJ Brinkman, AC Kaastra, JS van der Meer, RLJ Paerels, FB Burwitz, V Predehl, P Marshall, HL Barstow, MA Finley, DS Dupuis, J AF Pease, D Drake, JJ Johnson, CO Kashyap, V Kraft, RP Ratzlaff, PW Wargelin, BJ Brinkman, AC Kaastra, JS van der Meer, RLJ Paerels, FB Burwitz, V Predehl, P Marshall, HL Barstow, MA Finley, DS Dupuis, J BE Trumper, JE Aschenbach, B TI Low energy effective area of the Chandra low energy transmission grating spectrometer SO X-RAY OPTICS, INSTRUMENTS, AND MISSIONS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray Optics, Instruments, and Missions III CY MAR 27-29, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc DE Chandra; X-ray; X-ray spectroscopy; transmission grating; calibration ID BEPPOSAX; SPECTRUM; 3C-273; 3C273; ASCA AB The Chandra X-ray Observatory was successfully launched on July 23, 1999, and subsequently began an intensive calibration phase. We present preliminary results from in-flight calibration of the low energy response of the High Resolution Camera Spectroscopic readout (HRC-S) combined with the Low Energy Transmission Crating (LETG) aboard Chandra. These instruments comprise the Low Energy Transmission Orating Spectrometer (LETGS). For this calibration study, we employ a pure hydrogen non-LTE white dwarf emission model (T-eff = 25000 K and log g = 9.0) for comparison with the Chandra observations of Sirius B. Pre-flight calibration of the LETGS effective area was conducted only at wavelengths shortward of 45 Angstrom (E > 0.277 keV). Our Sirius B analysis shows that the HRC-S quantum efficiency (QE) model assumed for longer wavelengths overestimates the effective area on average by a factor of 1.6. We derive a correction to the low energy HRC-S QE model to match the predicted and observed Sirius B spectra over the wavelength range of 45-185 Angstrom. We make an independent test of our results by comparing a Chandra LETGS observation of HZ 43 with pure hydrogen model atmosphere predictions and find good agreement. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Pease, D (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 9 TC 10 Z9 10 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3637-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4012 BP 700 EP 711 DI 10.1117/12.391609 PG 12 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BQ70G UT WOS:000089219400068 ER PT S AU Gorenstein, P Ivan, A Bruni, RJ Romaine, SE Mazzoleni, F Pareschi, G Ghigo, M Citterio, O AF Gorenstein, P Ivan, A Bruni, RJ Romaine, SE Mazzoleni, F Pareschi, G Ghigo, M Citterio, O BE Hoover, RB Walker, ABC TI Integral shell mirrors for the Constellation X-ray Mission Hard X-ray Telescope SO X-RAY OPTICS, INSTRUMENTS, AND MISSIONS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray Optics, Instruments, and Missions IV CY JUL 30-31, 2000 CL SAN DIEGO, CA SP SPIE DE multilayers; X-ray telescopes; hard X-rays; X-ray astronomy ID CALIBRATION; REPLICATION; OPTICS AB Estimates of background in CZT detectors(1) indicate that even with the beneficial concentration of a focussing telescope measurements in the 20 to 100 keV band of the Constellation X-ray Mission's HXT will become background limited after several thousand seconds of observing. This time is less than the expected exposure of most measurements. Consequently the sensitivity of most if not all observations of the HXT will be background limited. Therefore, the angular resolution should be as good as possible as long as the effective area remains high. We are pursuing a method for fabricating telescopes for the twelve units of HXT that consists of electroforming integral shell substrates, a process that has been highly developed for XMM. We are attempting to adapt this method to higher energy X-rays by employing multilayer coatings, and smaller graze angles, and also reduce the mass of the telescopes from the XMM prescription by employing stronger, lighter alloys. The resolution that XMM has achieved, 15 " HPW is an indication of the resolution we can expect. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Gorenstein, P (reprint author), Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NR 7 TC 8 Z9 8 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3783-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4138 BP 10 EP 15 DI 10.1117/12.407562 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BR62F UT WOS:000166964200002 ER PT S AU Romaine, S Ivan, A Bruni, R Christensen, F Harrison, F Craig, W Gorenstein, P AF Romaine, S Ivan, A Bruni, R Christensen, F Harrison, F Craig, W Gorenstein, P BE Hoover, RB Walker, ABC TI Multilayer optics for hard X-ray astronomy SO X-RAY OPTICS, INSTRUMENTS, AND MISSIONS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray Optics, Instruments, and Missions IV CY JUL 30-31, 2000 CL SAN DIEGO, CA SP SPIE DE X-ray Telescopes; Multilayers; X-ray optics AB We are engaged in a program to develop focusing hard X-ray optics for future X-ray astronomy missions (such as the Hard X-ray Telescope of Constellation-X) and have built a DC magnetron sputtering system to deposit multilayers on candidate substrates for future telescopes. Although our emphasis is on the multilayer coating of integral cylindrical optics which will provide the highest spatial resolution, other types of substrates can easily be coated in this system. We present specular reflectivity data (using CuKalpha X-rays) of W/Si constant d and depth graded-d multilayer depositions on substrates such as thermally formed DESAG glass and Duran glass cylinders. We will present data to show both azimuthal and linear uniformity of these coatings. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Romaine, S (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3783-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4138 BP 120 EP 125 DI 10.1117/12.407551 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BR62F UT WOS:000166964200014 ER PT S AU Bergner, HW Cohen, LM Schattenburg, ML Monnelly, G AF Bergner, HW Cohen, LM Schattenburg, ML Monnelly, G BE Hoover, RB Walker, ABC TI Precision assembly station for high resolution segmented optics SO X-RAY OPTICS, INSTRUMENTS, AND MISSIONS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray Optics, Instruments, and Missions IV CY JUL 30-31, 2000 CL SAN DIEGO, CA SP SPIE DE Constellation-X; etched silicon; precision tooling; segmented x-ray optics; SPIE Proceedings AB Historically, segmented optics similar to those used in BBXRT and ASTRO have achieved resolutions of a few are minutes. Achieving substantially better performance requires significant improvement in both the optics themselves and how the optics are assembled and mounted to flight structure. While techniques for improving the optics themselves are underway at Goddard Space Flight Center (GSFC), Columbia University, and Smithsonian Astrophysical Observatory (SAO), here we address how the optics are assembled and mounted to flight structure. We have developed a concept for mounting large numbers of nested, segmented optics which require sub micron accuracy. This methodology uses lithographically defined and etched silicon alignment micro structures. A precision assembly station, incorporating the silicon micro structures is used to position the optics which are then bonded to a flight structure. The advantages of this procedure are that the flight structure has relaxed tolerance requirements and the precision assembly tooling can be reused. We show the positional requirements of the precision tooling as well as the mechanical requirements of the tooling itself. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Bergner, HW (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 7 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3783-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4138 BP 134 EP 146 PG 13 WC Engineering, Aerospace; Astronomy & Astrophysics; Instruments & Instrumentation; Optics SC Engineering; Astronomy & Astrophysics; Instruments & Instrumentation; Optics GA BR62F UT WOS:000166964200016 ER PT B AU Romanowsky, AJ Kochanek, CS AF Romanowsky, AJ Kochanek, CS BE Combes, F Mamon, GA Charmandaris, V TI Halo dynamics of M 87 SO XVTH IAP MEETING DYNAMICS OF GALAXIES: FROM THE EARLY UNIVERSE TO THE PRESENT SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT XVth IAP Meeting on Dynamics of Galaxies - From the Early Universe to the Present CY JUL 09-13, 1999 CL INST ASTROPHYS PARIS, PARIS, FRANCE SP Inst Astrophy Paris, CNRS, Observatoire Paris, European Space Agcy, European Assoc Res Astron, Groupment Rech Galaxies, Silicon Graph Cray Res HO INST ASTROPHYS PARIS ID GLOBULAR-CLUSTERS; M87; GALAXIES; SYSTEM AB We examine the dynamics of the stars and globular clusters in the nearby giant galaxy M87 and constrain the mass distribution using all the available kinematical data, including higher-order moments of the stellar line-of-sight velocity distributions and the discrete velocities of more than 200 globular clusters. Employing a robust orbit modeling method that makes full use of all the information in the data, we rule out both a constant mass-to-light ratio model and a singular isothermal mass model. Our results imply the presence of a dark halo with a radial density profile that falls off more slowly than r(-2), suggesting that the potential of the Virgo Cluster is already dominant at r similar to 20 kpc. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Romanowsky, AJ (reprint author), Harvard Smithsonian Ctr Astrophys, MS 10, Cambridge, MA 02138 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-024-2 J9 ASTR SOC P PY 2000 VL 197 BP 401 EP 402 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ13Z UT WOS:000087283000112 ER PT S AU Lieberman, DE Ross, CF Ravosa, MJ AF Lieberman, DE Ross, CF Ravosa, MJ BE Ruff, C TI The primate cranial base: Ontogeny, function, and integration SO YEARBOOK OF PHYSICAL ANTHROPOLOGY, VOL 43 2000 SE Yearbook of Physical Anthropology LA English DT Article DE cranial base; basicranium; chondrocranium; primates; humans ID RELATIVE BRAIN SIZE; UNRESTRAINED AWAKE ANIMALS; PLIO-PLEISTOCENE HOMINIDS; CERVICAL VERTEBRAL COLUMN; UPPER RESPIRATORY SYSTEMS; ADDUCTOR MUSCLE FORCE; BASICRANIAL FLEXION; DEVELOPMENTAL INTEGRATION; MORPHOLOGICAL INTEGRATION; CIRCUMORBITAL MORPHOLOGY AB Understanding the complexities of cranial base development, function, and architecture is important for testing hypotheses about many aspects of craniofacial variation and evolution. We summarize key aspects of cranial base growth and development in primates that are useful for formulating and testing hypotheses about the roles of the chondrocranium and basicranium in cranial growth, integration, and function in primate and human evolution. We review interspecific, experimental, and ontogenetic evidence for interactions between the cranial base and brain, and between the cranial base and the face. These interactions indicate that the cranial base plays a key role in craniofacial growth, helping to integrate, spatially and functionally, different patterns of growth in various adjoining regions of the skull such as components of the brain, the eyes, the nasal cavity, the oral cavity, and the pharynx. Brain size relative to cranial. base length appears to be the dominant influence on many aspects of basicranial variation, especially the angle of the cranial base in the midsagittal plane, but other factors such as facial size, facial orientation, and posture may also be important. Major changes in cranial base shape appear to have played crucial roles in the evolution of early primates, the origin of anthropoids, and the origin of Homo sapiens. Yrbb Phys Anthropol 43:117-169, 2000. (C) 2000 Wiley-Liss, Inc. C1 George Washington Univ, Dept Anthropol, Washington, DC 20052 USA. Smithsonian Inst, Natl Museum Nat Hist, Human Origins Program, Washington, DC 20560 USA. SUNY Stony Brook, Hlth Sci Ctr, Dept Anat Sci, Stony Brook, NY 11794 USA. Northwestern Univ, Sch Med, Dept Cell & Mol Biol, Chicago, IL 60611 USA. Field Museum Nat Hist, Dept Zool, Div Mammals, Chicago, IL 60605 USA. RP Lieberman, DE (reprint author), George Washington Univ, Dept Anthropol, Washington, DC 20052 USA. NR 286 TC 159 Z9 163 U1 6 U2 19 PU WILEY-LISS, INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0096-848X J9 YEARB PHYS ANTHROPOL JI Yearb. Phys. Anthropol. PY 2000 VL 43 BP 117 EP 169 PG 53 WC Anthropology SC Anthropology GA BR64H UT WOS:000167044800004 PM 11123839 ER PT J AU Hildebrandt, TB Goritz, F Pratt, NC Brown, JL Montali, RJ Schmitt, DL Fritsch, G Hermes, R AF Hildebrandt, TB Goritz, F Pratt, NC Brown, JL Montali, RJ Schmitt, DL Fritsch, G Hermes, R TI Ultrasonography of the urogenital tract in elephants (Loxodonta africana and Elephas maximus): An important tool for assessing female reproductive function SO ZOO BIOLOGY LA English DT Article DE elephant; reproductive anatomy; ultrasonography; breeding evaluation; ovary; uterus AB At present, the worldwide captive elephant population is not self-sustaining. The major reason for low reproductive rates is the heretofore undiagnosed reproductive disorders of nulliparous females of prime breeding age. Recent advances in ultrasound technology have facilitated the detection of these disorders in non-sedated animals. Approximately 2,000 ultrasonographic examinations were performed in more than 280 captive and wild African and captive Asian female elephants. The entire urogenital tract was scanned, measured, and documented to provide a reference for ultrasound specialists involved in elephant breeding programs. The primary pathological lesions that influenced reproductive rates in these females were uterine tumors and endometrial cysts and ovarian cysts that resulted in acyclicity. The detection of these disorders and their stage of development can be used by elephant managers to make decisions approximately which animals to include in breeding programs. Ultrasonography can be used as an effective tool for assessing the reproductive fitness of female breeding candidates in both African and Asian elephants. Zoo Biol 19:321-332, 2000. (C) 2000 Wiley-Liss, Inc. C1 Inst Zoo Biol & Wildlife Res, Dept Reprod Management, D-10315 Berlin, Germany. Disneys Anim Kingdom, Lake Buena Vista, FL USA. Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA USA. Smithsonian Inst, Natl Zool Pk, Dept Pathol, Front Royal, VA USA. SW Missouri State Univ, Dept Agr, Springfield, MO 65802 USA. RP Hildebrandt, TB (reprint author), Inst Zoo Biol & Wildlife Res, Dept Reprod Management, Alfred Kowalke Str 17, D-10315 Berlin, Germany. NR 19 TC 44 Z9 46 U1 1 U2 14 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0733-3188 J9 ZOO BIOL JI Zoo Biol. PY 2000 VL 19 IS 5 BP 321 EP 332 DI 10.1002/1098-2361(2000)19:5<321::AID-ZOO4>3.0.CO;2-K PG 12 WC Veterinary Sciences; Zoology SC Veterinary Sciences; Zoology GA 376XY UT WOS:000165483100004 ER PT J AU Hildebrandt, TB Hermes, R Pratt, NC Fritsch, G Blottner, S Schmitt, DL Ratanakorn, P Brown, JL Rietschel, W Goritz, F AF Hildebrandt, TB Hermes, R Pratt, NC Fritsch, G Blottner, S Schmitt, DL Ratanakorn, P Brown, JL Rietschel, W Goritz, F TI Ultrasonography of the urogenital tract in elephants (Loxodonta africana and Elephas maximus): An important tool for assessing male reproductive function SO ZOO BIOLOGY LA English DT Article DE male elephant; reproductive anatomy; ultrasonography; breeding evaluation; accessory sex glands; sperm; testis ID SEMEN AB The success rate of captive elephant breeding programs worldwide is poor. Along with undiagnosed reproductive disorders in females and fatal diseases such as the newly discovered herpesvirus infection, male infertility now is considered a major contributing factor in the failure to maintain self-sustaining captive populations. To address questions related to male reproductive dysfunction, approximately 309 ultrasonographic assessments combined with semen collection were performed in captive (n = 10) and wild (n = 4) African (Loxodonta africana) and captive (n = 61) Asian (Elephas maximus) elephants. Bulls ranged from 4 to 50 years of age and were examined at 9 institutions in North America, 13 in Europe, 2 in Africa, and 7 in Asia. About half of the reproductive assessments were performed in protected contact situations with elephants handled in a restraint device, and half involved assessments of trained Asian bulls managed in free contact. Four wild African and two Asian elephant bulls were evaluated after receiving general anesthesia. Transrectal ultrasound was used to characterize the morphology and functionality of the entire urogenital tract, including the testes and accessory sex organs. Bulls were categorized on the basis of breeding status (breeders vs. non-breeders) and social history (i.e., type of interaction with conspecifics and keepers). Most of the bulls were non-breeders (designated Types I-V). Type I (n = 3 African, 6 Asian) and Type V (n = 1 Asian) were immature and castrate, respectively. On the basis of keeper evaluations, Type II bulls (n = 2, 4) were subordinate to older cows and keepers, whereas Type LII bulls (n = 4, 28) were dominated by other bulls. Type TV (n = 1, 8) were older bulls of unknown history that exhibited numerous testicular pathologies resulting in poor semen quality. Non-breeding bulls included those that were exposed to females, but failed to breed, as well as these that had no opportunities to breed. Type VI individuals (n = 4, 14) were proven breeders. The percentage of observable reproductive tract pathology in adult males was remarkably low (14%), even in older bulls. However, apparent infertility of non-organic cause (i.e., not due to specific anatomical abnormalities) in these otherwise healthy bulls was high (32%). Semen quality varied markedly in ejaculates collected from the same bull, as well as from different bulls. In conclusion, although many of these bulls could serve as semen donors for natural mating or artificial insemination, the inconsistent production of good-quality ejaculates raises questions as to the reliability of these individuals to participate in breeding programs. The apparent inhibitory effect of suppressive social interactions on reproductive potential also needs to be investigated. Ultrasound examinations combined with semen collection should be conducted periodically to estimate the reproductive value of each bull and determine whether altered management strategies are needed to enhance captive breeding. Zoo Biol 19:333-345, 2000. (C) 2000 Wiley-Liss, Inc. C1 Inst Zoo Biol & Wildlife Res, D-10315 Berlin, Germany. Disneys Anim Kingdom, Lake Buena Vista, FL USA. SW Missouri State Univ, Dept Agr, Springfield, MO 65802 USA. Mahidol Univ, Fac Vet Sci, Nakhonpathom, Thailand. Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA USA. Wilhelma Zool & Bot Garden, Stuttgart, Germany. RP Hildebrandt, TB (reprint author), Inst Zoo Biol & Wildlife Res, Alfred Kowalke Str 17, D-10315 Berlin, Germany. NR 17 TC 31 Z9 33 U1 2 U2 16 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0733-3188 J9 ZOO BIOL JI Zoo Biol. PY 2000 VL 19 IS 5 BP 333 EP 345 DI 10.1002/1098-2361(2000)19:5<333::AID-ZOO5>3.0.CO;2-A PG 13 WC Veterinary Sciences; Zoology SC Veterinary Sciences; Zoology GA 376XY UT WOS:000165483100005 ER PT J AU Brown, JL AF Brown, JL TI Reproductive endocrine monitoring of elephants: An essential tool for assisting captive management SO ZOO BIOLOGY LA English DT Article DE hormones; progestogens; estrous cycle; pregnancy; non-invasive monitoring; testis ID LOXODONTA-AFRICANA ELEPHANTS; TEMPORAL GLAND SECRETIONS; LUTEINIZING-HORMONE; ASIAN ELEPHANTS; ESTROUS-CYCLE; PROGESTERONE SECRETION; SERUM PROGESTERONE; ADRENAL ACTIVITY; OVARIAN-FUNCTION; MAXIMUS AB Considerable information now is available about the basic reproductive biology of elephants, especially females. However, as important as this knowledge is, it no longer is enough to simply compile it into a database. The potential exists for using endocrine monitoring techniques to solve real problems. This review summarizes our current knowledge of elephant endocrinology and offers suggestions on how to use the technology to maximize reproductive potential. The estrous cycle can be monitored through the analysis of serum progestogens, primarily Sa-reduced compounds, and consists of an 8- to 12-week luteal phase and a 4- to 6-week inter-luteal period. Proof of ovarian cyclicity currently is mandatory before Species Survival Plan breeding recommendations are approved. However, because many adult females are not cycling normally, the reproductive monitoring of all cows throughout their life span is now encouraged. Complete endocrine evaluations in conjunction with ultrasound examinations and behavioral assessments are needed to identify causes of reproductive failure and develop mitigating treatments. Progestogen analyses also are effective for monitoring pregnancy, but only if longitudinal samples are collected. Alternatively, pregnancy can be diagnosed in occasional samples using serum prolactin or possibly relaxin measurements after 20 weeks of gestation. Parturition can be predicted on the basis of the rapid decrease in progestogens that occurs about 2-5 days before birth. An updated model of ovarian dynamics during the estrous cycle suggests that two waves of follicular development occur 3 weeks apart during the nonluteal phase, possibly under the control of follicle-stimulating hormone. Each follicular wave culminates in a luteinizing hormone (LH) surge, with the second surge inducing ovulation and corpus luteum formation. The functional significance of the first, anovulatory LH surge is under investigation, but from a practical perspective it can be used to schedule breeding (by artificial insemination or natural mating) to coincide with the ovulatory LH surge. Less is known about the reproductive biology of bulls, aside from the fact that musth is associated with dramatic changes in androgen secretion. Studies are needed to determine whether poor libido and inadequate semen quality observed in some mature elephants are due to testicular steroidogenic dysfunction. When blood samples cannot be collected for routine hormone analysis, gonadal activity can be monitored non-invasively through the measurement of excreted steroid metabolites (males: androgens; females: estrogens, progestogens) in urine and feces. Lastly, suggestions for future research priorities are provided. Zoo Biol 19:347-367, 2000. (C) 2000 Wiley-Liss, Inc. C1 Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA 22630 USA. RP Brown, JL (reprint author), Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, 1500 Remount Rd, Front Royal, VA 22630 USA. NR 72 TC 87 Z9 91 U1 3 U2 31 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0733-3188 J9 ZOO BIOL JI Zoo Biol. PY 2000 VL 19 IS 5 BP 347 EP 367 DI 10.1002/1098-2361(2000)19:5<347::AID-ZOO6>3.0.CO;2-V PG 21 WC Veterinary Sciences; Zoology SC Veterinary Sciences; Zoology GA 376XY UT WOS:000165483100006 ER PT J AU Hermes, R Olson, D Goritz, F Brown, JL Schmitt, DL Hagan, D Peterson, JS Fritsch, G Hildebrandt, TB AF Hermes, R Olson, D Goritz, F Brown, JL Schmitt, DL Hagan, D Peterson, JS Fritsch, G Hildebrandt, TB TI Ultrasonography of the estrous cycle in female African elephants (Loxodonta africana) SO ZOO BIOLOGY LA English DT Article DE ultrasound; ovarian dynamic; follicular waves; ovulation ID LUTEINIZING-HORMONE; PROGESTERONE SECRETION; MAXIMUS; PREGNANCY AB The endocrinology of the elephant estrous cycle has been well characterized, but little emphasis has been placed on evaluating corresponding changes in the reproductive tract. Ultrasound was used to document changes in reproductive tract morphology throughout the estrous cycle in four cycling female African elephants. During a 7-month period, frequent ultrasound examinations (n = 190) during the luteal and non-luteal phase were compared with serum progesterone and luteinizing hormone (LH) concentrations during a 7-month period. Ultrasonographic images documented vaginal and cervical edema and changes in mucus consistency during the non-luteal phase. The cross-sectional diameter of the endometrium showed a dramatic increase during the non-luteal phase and followed cyclic changes. A different pattern of follicular development on the ovary was associated with the two LH surges. Follicle growth associated with the first, anovulatory LH surge was characterized by the formation of multiple small follicles, in contrast to the maturation of a single large follicle at the second, ovulatory LH (ovLH) surge. Ovulation and the subsequent formation of a corpus luteum (CL) were observed only after the ovLH surge. Ultrasound data in combination with endocrine assessments suggest that the African elephant is non-ovulatory, although multiple non-ovulatory luteal structures developed during the late nonluteal phase of each cycle. Both ovulatory CL and non-ovulatory luteal structures were present only through one cycle and regressed at the end of the luteal phase in conjunction with the drop in serum progesterone. We conclude that periodic reproductive-tract ultrasound assessments in association with continued endocrine monitoring of the estrous cycle should be incorporated into the routine reproductive health assessment of elephants. This information is necessary for determining reproductive fitness before making breeding recommendations. It also has proven to be an invaluable tool for use with assisted reproductive techniques and has enormous potential for evaluating the efficiency of hormonal therapies used to treat reproductive dysfunction. Zoo Biol 19:369-382, 2000. (C) 2000 Wiley-Liss. Inc. C1 Inst Zoo Biol & Wildlife Res, Reprod Management Res Grp, D-10315 Berlin, Germany. Indianapolis Zoo, Indianapolis, IN USA. Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA USA. SW Missouri State Univ, Dept Agr, Springfield, MO 65802 USA. RP Hermes, R (reprint author), Inst Zoo Biol & Wildlife Res, Reprod Management Res Grp, Alfred Kowalke Str 17, D-10315 Berlin, Germany. NR 37 TC 37 Z9 38 U1 0 U2 9 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0733-3188 J9 ZOO BIOL JI Zoo Biol. PY 2000 VL 19 IS 5 BP 369 EP 382 DI 10.1002/1098-2361(2000)19:5<369::AID-ZOO7>3.0.CO;2-K PG 14 WC Veterinary Sciences; Zoology SC Veterinary Sciences; Zoology GA 376XY UT WOS:000165483100007 ER PT J AU Richman, LK Montali, RJ Hayward, GS AF Richman, LK Montali, RJ Hayward, GS TI Review of a newly recognized disease of elephants caused by endotheliotropic herpesviruses SO ZOO BIOLOGY LA English DT Article DE Elephas maximus; famciclovir; Loxodonta africana; endotheliotropic virus ID AFRICAN ELEPHANTS AB There are two newly recognized herpesviruses that cause a fatal disease syndrome in elephants. They are known as the elephant endotheliotropic herpesviruses, of which one is fatal for Asian elephants (Elephas maximus) and the other for African elephants (Loxodonta africana) [Richman et al., Science 283:1171-1176, 1999a]. The disease syndrome affects predominantly young elephants and has been described in North America [Richman et al., J Wildl Dis 36:1-12, 2000], Europe [Richman et al., Verhandlangsbericht des 39 International Symposium uben Erkrankungen der Zoo und Wildtiere, Wien, 39:17-21, 1999b; Ossent et al., Vet Pathol 27:131-133, 1990], and Israel [Richman et al., Verhandlangsbericht des 39 International Symposium uben Erkrankungen der Zoo und Wildtiere, Wien, 39:17-21, 1999b]. The predominant clinical signs for both species include lethargy, edematous swellings of the head, neck, and thoracic limbs, oral ulceration, cyanosis of the tongue, and death of most elephants in 1-7 days [Richman et al., J Wildl Dis 36:1-12, 2000]. Three affected young Asian elephants recovered after a 3-4-week course of therapy with the anti-herpesvirus drug famciclovir [Richman et al., J Wildl Dis 36:1-12, 2000; Schmitt and Hardy, J Elephant Managers Assoc 9:103-4, 1998]. Additional reported herpesvirus-associated lesions in otherwise healthy elephants include localized skin papillomas in African elephants [Richman et al., Science 283:1171-1176, 1999a; Jacobson et al., J Am Vet Med Assoc 189:1075-8, 1986], proliferative vulval lymphoid patches in African elephants [Richman et al., Science 283:1171-1176, 1999a; Munson et al., J Zoo Wildl Med 26:353-8, 1995], and pulmonary nodules in African elephants [Richman et al., J Wildl Dis 36:1-12, 2000; McCulley et al., Onderstepoort J Vet Res 38:225-236, 1971]. Recent findings suggest that these localized herpesvirus-associated lesions in healthy African elephants may be one source of the herpesvirus that causes disseminated disease and death in the Asian species [Richman et al., Science 283:1171-1176, 1999a] and the African species [Richman et al., J Wildl Dis 36:1-12, 2000]. These findings have implications for management practices in facilities keeping both African and Asian elephants and in protecting natural elephant habitats from virulent forms of the virus. Zoo Biol 19:383-392, 2000. (C) 2000 Wiley-Liss, Inc. C1 Johns Hopkins Univ, Sch Med, Baltimore, MD 21205 USA. Smithsonian Inst, Natl Zool Pk, Washington, DC 20008 USA. RP Richman, LK (reprint author), Johns Hopkins Univ, Sch Med, Hunterian 513,725 N Wolfe St, Baltimore, MD 21205 USA. NR 10 TC 18 Z9 20 U1 2 U2 5 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0733-3188 J9 ZOO BIOL JI Zoo Biol. PY 2000 VL 19 IS 5 BP 383 EP 392 DI 10.1002/1098-2361(2000)19:5<383::AID-ZOO8>3.3.CO;2-O PG 10 WC Veterinary Sciences; Zoology SC Veterinary Sciences; Zoology GA 376XY UT WOS:000165483100008 ER PT J AU Mikota, SK Larsen, RS Montali, RJ AF Mikota, SK Larsen, RS Montali, RJ TI Tuberculosis in elephants in North America SO ZOO BIOLOGY LA English DT Article DE Loxodonta africana; Elephas maximus; tuberculosis; bacterial disease ID MYCOBACTERIUM-TUBERCULOSIS; DIAGNOSIS; SPECIMENS; INFECTION; CATTLE; ASSAY; PCR AB Within the past 4 years, tuberculosis (TB) has emerged as a disease of concern in elephants. The population of elephants in North America is declining [Wiese, 1997], and transmissible diseases such as TB may exacerbate this trend. Guidelines for the Control of Tuberculosis in Elephants, which require the screening of all elephants for TB, were instituted in 1997 [USDA, 1997; 2000]. Between August 1996 and May 2000, Mycobacterium tuberculosis was isolated from 18 of 539 elephants in North America, indicating an estimated prevalence of 3.3%. Isolation of the TB orga nism by culture is the currently recommended test to establish a diagnosis of TB; however, culture requires 8 weeks. Further research is essential to validate other diagnostic tests and treatment protocols. Zoo Biol 19.393-403, 2000. (C) 2000 Wiley-Liss, Inc. C1 Smithsonian Natl Zool Pk, Dept Pathol, Washington, DC 20008 USA. Colorado State Univ, Coll Vet Med & Biomed Sci, Dept Clin Sci, Ft Collins, CO 80523 USA. Audubon Ctr Res Endangered Species, New Orleans, LA USA. RP Montali, RJ (reprint author), Smithsonian Natl Zool Pk, Dept Pathol, Washington, DC 20008 USA. NR 47 TC 25 Z9 27 U1 0 U2 11 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0733-3188 J9 ZOO BIOL JI Zoo Biol. PY 2000 VL 19 IS 5 BP 393 EP 403 DI 10.1002/1098-2361(2000)19:5<393::AID-ZOO9>3.0.CO;2-T PG 11 WC Veterinary Sciences; Zoology SC Veterinary Sciences; Zoology GA 376XY UT WOS:000165483100009 ER PT J AU Wolf, KN Wildt, DE Vargas, A Marinari, PE Ottinger, MA Howard, JG AF Wolf, KN Wildt, DE Vargas, A Marinari, PE Ottinger, MA Howard, JG TI Reproductive inefficiency in male blackfooted ferrets (Mustela nigripes) SO ZOO BIOLOGY LA English DT Article DE behavior; breeding; copulation; semen; mustelid ID BLACK-FOOTED FERRET; PUTORIUS-FURO; CONSERVATION; SECRETION; BIOLOGY AB The black-footed ferret (Mustela nigripes), once considered extinct, has benefited from captive breeding and subsequent reintroduction into native habitat. A high proportion of females (>90%) exhibit estrus in captivity during the spring breeding season. However, many males considered to be prime-breeding age (1-3 years old) fail to sire offspring. Breeding records in 1995 revealed that 40 of 73 males (55%) managed under the Black-Footed Ferret Species Survival Plan did not reproduce, despite being provided opportunity. The present study was conducted to determine the incidence and etiology of male reproductive failure in 1996 and 1997. In 1996, 38 of 69 (55%) 1- to 3-year-old males failed to sire offspring. Likewise, 35 of 60 (58%) males did not reproduce in 1997. Overall, 21% of adult males failed to sire young in three consecutive breeding seasons (1995-1997). Electroejaculate traits (ejaculate volume, sperm concentration, motility, morphology, and acrosomal integrity) from 29 proven breeder males were not different (P > 0.05) from those of 23 males that did not sire young (nonproven breeders). However, six categories of reproductive failure were identified for the 73 prime-breeding age, nonproven males: 1) underdeveloped testes (22%); 2) improper breeding position with the female (25%); 3) excessive aggression toward estrous females (9%); 4) copulation with no sperm detected at postcoital lavage (19%); 5) copulation with sperm in the vaginal lavage but no resulting pregnancy (18%); and 6) copulation with no vaginal lavage performed and no resulting pregnancy (7%). These data indicate that combined behavioral and physiologic factors, but not overall sperm quality, influence reproductive performance in male black-footed ferrets managed in captivity. Zoo Biol 19:517-528, 2000. (C) 2000 Wiley-Liss, Inc. C1 Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA USA. Univ Wyoming, US Fish & Wildlife Serv, Natl Black Footed Ferret Conservat Ctr, Laramie, WY 82071 USA. Univ Maryland, Dept Anim & Avian Sci, College Pk, MD 20742 USA. RP Howard, JG (reprint author), Smithsonian Inst, Natl Zool Pk, Dept Reprod Sci, Washington, DC 20008 USA. NR 28 TC 25 Z9 26 U1 2 U2 20 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0733-3188 J9 ZOO BIOL JI Zoo Biol. PY 2000 VL 19 IS 6 BP 517 EP 528 DI 10.1002/1098-2361(2000)19:6<517::AID-ZOO4>3.0.CO;2-V PG 12 WC Veterinary Sciences; Zoology SC Veterinary Sciences; Zoology GA 394MU UT WOS:000166528500004 ER PT J AU Kensley, B Schotte, M AF Kensley, B Schotte, M TI New records of isopods from the Indian River Lagoon, Florida (Crustacea : Peracarida) SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article ID REDESCRIPTION; ATLANTIC AB Fifteen species of isopod are recorded for the first time as occurring in the Indian River Lagoon. Two species are described as new: the janirid asellote lais floridana, n. sp., which occurs commensally with Sphaeroma terebrans in low salinity water, and the sphaeromatid flabelliferan Sphaeromopsis sanctaluciae, n. sp., which is also recorded from the Orange River, Lee County, Florida, and from Islas de Juventud, Cuba. A brief discussion of protogyny in the sphaeromatid Paradella dianae is included. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Kensley, B (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. NR 55 TC 2 Z9 5 U1 0 U2 2 PU BIOL SOC WASHINGTON PI WASHINGTON PA NAT MUSEUM NAT HIST SMITHSONIAN INST, WASHINGTON, DC 20560 USA SN 0006-324X EI 1943-6327 J9 P BIOL SOC WASH JI Proc. Biol. Soc. Wash. PD DEC 29 PY 1999 VL 112 IS 4 BP 695 EP 713 PG 19 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 273UZ UT WOS:000084727400007 ER PT J AU Rambla, JPB Lemaitre, R AF Rambla, JPB Lemaitre, R TI Neocallichirus raymanningi, a new species of ghost shrimp from the northeastern coast of Venezuela (Crustacea : Decapoda : Callianassidae) SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article ID CARIBBEAN SEA; THALASSINIDEA AB A new species of ghost shrimp, Neocallichirus raymanningi, is described based on specimens collected in subtidal habitats in the Gulf of Cariaco, northeastern Venezuela. This new species is most similar to N. rathbunae (Schmitt), but differs from it primarily in having a broadly rounded rostrum, and in the case of males, unique armature of merus and dactylus on the major cheliped. A checklist of all known species in the world currently assigned to the genus Neocallichirus Sakai is included. C1 Univ Oriente, Inst Oceanog Venezuela, Cumana, Estado Sucre, Venezuela. Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Rambla, JPB (reprint author), Univ Oriente, Inst Oceanog Venezuela, Apartado Postal 245, Cumana, Estado Sucre, Venezuela. NR 18 TC 2 Z9 2 U1 0 U2 1 PU BIOL SOC WASHINGTON PI WASHINGTON PA NAT MUSEUM NAT HIST SMITHSONIAN INST, WASHINGTON, DC 20560 USA SN 0006-324X EI 1943-6327 J9 P BIOL SOC WASH JI Proc. Biol. Soc. Wash. PD DEC 29 PY 1999 VL 112 IS 4 BP 768 EP 777 PG 10 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 273UZ UT WOS:000084727400014 ER PT J AU Graves, GR AF Graves, GR TI Taxonomic notes on hummingbirds (Aves : Trochilidae) 2. Popelairia letitiae (Bourcier & Mulsant, 1852) is a valid species SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article ID HYBRID ORIGIN; INTERGENERIC HYBRID; DIAGNOSES AB Popelairia letitiae (Bourcier & Mulsant, 1852), known from two specimens supposedly from Bolivia, appears to be a valid species. Analysis of plumage color and morphometrics indicates that P. letitiae does not represent an immature plumage or geographic variant of Discosura longicauda, although this species and P. letitiae may be sister taxa. No credible evidence for a hybrid origin of P. letitiae was discovered. "Letitia's Coquette" is proposed as the common English name for P. letitiae. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Vertebrate Zool, Washington, DC 20560 USA. RP Graves, GR (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Vertebrate Zool, Washington, DC 20560 USA. NR 34 TC 7 Z9 7 U1 0 U2 0 PU BIOL SOC WASHINGTON PI WASHINGTON PA NAT MUSEUM NAT HIST SMITHSONIAN INST, WASHINGTON, DC 20560 USA SN 0006-324X J9 P BIOL SOC WASH JI Proc. Biol. Soc. Wash. PD DEC 29 PY 1999 VL 112 IS 4 BP 804 EP 812 PG 9 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 273UZ UT WOS:000084727400018 ER PT J AU Carleton, MD Fisher, RD Gardner, AL AF Carleton, MD Fisher, RD Gardner, AL TI Identification and distribution of cotton rats, genus Sigmodon (Muridae : Sigmodontinae), of Nayarit, Mexico SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article ID MUROID RODENTS; MORPHOLOGICAL EVOLUTION; ZYGODONTOMYS; GROWTH AB Morphological, chromosomal, distributional, and ecological data are presented for three species of Sigmodon (S. alleni, S. arizonae, and S. mascotensis) from the state of Nayarit, Mexico. The species were collected in all possible pairwise combinations of sympatry, including the first record of such documented for S. arizonae and S. mascotensis. Emphasis is devoted to the discrimination of S. arizonae and S. mascotensis, from each other and from typical S. hispidus, using qualitative features of the skin and skull and morphometric analyses of craniodental measurements. Based on these results and examination of type specimens, additional synonyms of S. mascotensis are identified, with reassignment of two forms, tonalensis Bailey (1902) and obvelatus Russell (1952), currently mistaken as subspecies of S. hispidus. Sigmodon mascotensis emerges as a species distributed from southern Nayarit and Zacatecas to extreme western Chiapas, where it inhabits deciduous or semideciduous tropical vegetation having a pronounced dry season. These reallocations and other reidentifications remove any documentation for S. hispidus along the entire Pacific versant of Mexico. C1 Smithsonian Inst, Natl Museum Nat Hist, Div Mammals, Washington, DC 20560 USA. US Geol Survey, Natl Museum Nat Hist, Biol Resources Div, Patuxent Wildlife Res Ctr, Washington, DC 20560 USA. RP Carleton, MD (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Div Mammals, Washington, DC 20560 USA. NR 77 TC 13 Z9 18 U1 0 U2 1 PU BIOL SOC WASHINGTON PI WASHINGTON PA NAT MUSEUM NAT HIST SMITHSONIAN INST, WASHINGTON, DC 20560 USA SN 0006-324X EI 1943-6327 J9 P BIOL SOC WASH JI Proc. Biol. Soc. Wash. PD DEC 29 PY 1999 VL 112 IS 4 BP 813 EP 856 PG 44 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 273UZ UT WOS:000084727400019 ER PT J AU Lewis, BR Gibson, ST Yoshino, K AF Lewis, BR Gibson, ST Yoshino, K TI Comment on "Ab initio dynamic dipole polarizabilities for O-2, its photoabsorption spectrum in the Schumann-Runge region, and long-range interaction coefficients for its dimer" [J-Chem. Phys. 109, 9802 (1998)] SO JOURNAL OF CHEMICAL PHYSICS LA English DT Letter ID BAND OSCILLATOR-STRENGTHS; ABSORPTION CROSS-SECTIONS; MOLECULAR-OXYGEN; HIGH-RESOLUTION; STATE; CONTINUUM; MODEL C1 Australian Natl Univ, Res Sch Phys Sci & Engn, Canberra, ACT 0200, Australia. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Lewis, BR (reprint author), Australian Natl Univ, Res Sch Phys Sci & Engn, Canberra, ACT 0200, Australia. NR 17 TC 0 Z9 0 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 22 PY 1999 VL 111 IS 24 BP 11236 EP 11237 DI 10.1063/1.480481 PG 2 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 265KB UT WOS:000084242200060 ER PT J AU Markevitch, M Vikhlinin, A Forman, WR Sarazin, CL AF Markevitch, M Vikhlinin, A Forman, WR Sarazin, CL TI Mass profiles of the typical relaxed galaxy clusters A2199 and A496 SO ASTROPHYSICAL JOURNAL LA English DT Article DE cooling flows; dark matter; galaxies : clusters : individual (A2199, A496); intergalactic medium; X-rays : galaxies ID X-RAY-CLUSTERS; FLUX-LIMITED SAMPLE; DARK-MATTER; COOLING FLOWS; TEMPERATURE; ROSAT; GAS; CONDENSATION; EQUILIBRIUM; UNIVERSE AB We present maps and radial profiles of the gas temperature in the nearby galaxy clusters A2199 and A496, which have the most accurate ASCA spectral data of all hot dusters. X-ray images, temperature maps, and the presence of moderate cooling hows indicate that these dusters are relaxed and therefore can provide reliable X-ray mass measurements under the assumption of hydrostatic equilibrium and thermal pressure support. The average cluster temperatures corrected for the presence of cooling flows are 4.8 +/- 0.2 and 4.7 +/- 0.2 keV (90% errors), respectively, which are 10% higher than the wide-beam single-temperature fits. Outside the central cooling-flow regions and within r approximate to 0.7 h(-1) Mpc covered by ASCA, the radial temperature profiles are similar to those of the majority of nearby relaxed dusters. They are accurately described by polytropic models with gamma = 1.17 +/- 0.07 for A2199 and gamma = 1.24(-0.11)(+0.88) for A496. We use these polytropic models to derive accurate total mass profiles. Within r = 0.5 h(-1) Mpc, which corresponds to a radius of overdensity 1000, r(1000), for these clusters (estimated from our mass profiles), the total mass values are (1.45 +/- 0.15) x 10(14) and (1.55 +/- 0.15) x 10(14) h(-1) M.. These values are 10% lower than those obtained assuming constant temperature. On the other hand, the values inside a gas core radius (0.07-0.13 h(-1) Mpc) are a factor of greater than or similar to 1.5 higher than the isothermal values. The gas mass fraction increases significantly with radius (by a factor of 3 between the X-ray core radius and r(1000)) and at r(1000) reaches similar values of 0.057 +/- 0.005 and 0.056 +/- 0.006 h(-3/2) for the two clusters, respectively. Our measured total mass profiles within r(1000) are remarkably well approximated by the Navarro, Frenk, & White "universal" profile. Since A2199 and A496 are typical relaxed clusters, the above findings should be relevant for most such systems. In particular, the observed similarity of the temperature profiles in nearby clusters appears to reflect the underlying "universal" dark matter profile. The upward revision of the mass values at small radii for the observed temperature profile compared with those derived assuming isothermality will resolve most of the discrepancy between the X-ray and strong lensing mass estimates. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Russian Acad Sci, Space Res Inst, Moscow 117901, Russia. Univ Virginia, Dept Astron, Charlottesville, VA 22903 USA. RP Markevitch, M (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. OI Forman, William/0000-0002-9478-1682 NR 63 TC 81 Z9 81 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 DEC 20 PY 1999 VL 527 IS 2 BP 545 EP 553 DI 10.1086/308124 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 270XD UT WOS:000084561700007 ER PT J AU Millard, J Branch, D Baron, E Hatano, K Fisher, A Filippenko, AV Kirshner, RP Challis, PM Fransson, C Panagia, N Phillips, MM Sonneborn, G Suntzeff, NB Wagoner, RV Wheeler, JC AF Millard, J Branch, D Baron, E Hatano, K Fisher, A Filippenko, AV Kirshner, RP Challis, PM Fransson, C Panagia, N Phillips, MM Sonneborn, G Suntzeff, NB Wagoner, RV Wheeler, JC TI Direct analysis of spectra of the Type Ic supernova SN1994I SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : individual (M51); radiative transfer; supernovae : general; supernovae : individual (SN 1994I) ID GAMMA-RAY BURST; 25 APRIL 1998; OPTICAL-SPECTRA; HELIUM; M51; EVOLUTION; LINES; HE; IA AB Synthetic spectra generated with the parameterized supernova synthetic-spectrum code SYNOW are compared to observed photospheric-phase spectra of the Type Ic supernova SN 1994I. The observed optical spectra can be well matched by synthetic spectra that are based on the assumption of spherical symmetry. We consider the identification of the infrared absorption feature observed near 10250 Angstrom which previously has been attributed to He I lambda 10830 and regarded as strong evidence that SN 1994I ejected some helium. We have difficulty accounting for the infrared absorption with He I alone. It could be a blend of He I and C I lines. Alternatively, we find that it can be fitted by Si I lines without compromising the fit in the optical region. In synthetic spectra that match the observed spectra, from 4 days before to 26 days after the time of maximum brightness, the adopted velocity at the photosphere decreases from 17,500 to 7000 km s(-1). Simple estimates of the kinetic energy carried by the ejected mass give values that are near the canonical supernova energy of 10(51) ergs. The velocities and kinetic energies that we find for SN 1994I in this way are much lower than those that we find elsewhere for the peculiar Type Ic SNe 1997ef and 1998bw, which therefore appear to have been hyperenergetic. C1 Univ Oklahoma, Dept Phys & Astron, Norman, OK 73019 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Stockholm Observ, S-13336 Saltsjobaden, Sweden. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Carnegie Inst Washington, Las Campanas Observ, La Serena, Chile. NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. Natl Opt Astron Observ, CTIO, La Serena, Chile. Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Univ Texas, Dept Astron, Austin, TX 78712 USA. RP Millard, J (reprint author), Univ Oklahoma, Dept Phys & Astron, Norman, OK 73019 USA. RI Baron, Edward/A-9041-2009 OI Baron, Edward/0000-0001-5393-1608 NR 33 TC 61 Z9 61 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1999 VL 527 IS 2 BP 746 EP 756 DI 10.1086/308108 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 270XD UT WOS:000084561700024 ER PT J AU Landecker, TL Routledge, D Reynolds, SP Smegal, RJ Borkowski, KJ Seward, FD AF Landecker, TL Routledge, D Reynolds, SP Smegal, RJ Borkowski, KJ Seward, FD TI DA 530: A supernova remnant in a stellar wind bubble SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : bubbles; ISM : individual (DA 530); radio continuum : ISM; supernova remnants; X-rays : ISM ID RADIO TELESCOPE; REGION AB The high-latitude supernova remnant (SNR) DA 530 (G93.3 + 6.9), apparently a typical shell remnant, has highly polarized radio continuum emission and a very uniform circumferential magnetic field. We present new radio continuum (408 and 1420 MHz) and H I line observations, made with the Dominon Radio Astrophysical Observatory Synthesis Telescope, and we have made the first detection of X-ray emission from the SNR, using the ROSAT Position-Sensitive Proportional Counter. The SNR lies within a shell of H I, possibly created by an earlier stellar wind, whose kinematic distance is nominally 2.5 kpc but whose actual distance may be larger. The X-ray emission is extremely faint. A Raymond-Smith ionization-equilibrium model fits the data and suggests a very low density, similar to 0.05 cm(-3), consistent with the occurrence of the supernova in a stellar wind cavity, but this model yields an explosion energy 100 times lower than the accepted value. A nonequilibrium shock model, incorporating a range of ionization timescales, is able to give more realistic physical parameters for the supernova remnant. On the balance of the evidence, we place DA 530 at a distance of 3.5 kpc, the largest distance permitted by the H I observations, where it lies 420 pc above the Galactic plane. The explosion, probably a Type Ia supernova, in a low-density cavity has resulted in weak X-ray emission and slow evolution. The explosion energy was 3.9 x 10(50) ergs and the age is similar to 5000 years. The remnant, having swept up 3.9 M. in an ambient density of similar to 0.01 cm(-3), is only now in the adiabatic phase, and this explains the absence of detected optical emission. Despite the low ambient density the efficiency of generation of synchrotron radio emission is similar to 0.4%, higher than in some historical SNRs. The ratio of radio to X-ray flux is about 100 times that for the remnant of SN 1006, which has comparable radio continuum properties. The very uniform magnetic field is not explained. DA 530 joins a small group of remnants at high Galactic latitude with unusual features, perhaps resulting from low ambient densities. Inhomogeneous nonequilibrium ionization models may be required for the interpretation of the X-ray emission from many other older SNRs. C1 Natl Res Council Canada, Herzberg Inst Astrophys, Dominion Radio Astrophys Observ, Penticton, BC V2A 6K3, Canada. Univ Alberta, Dept Elect Engn, Edmonton, AB T6G 2G7, Canada. N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Landecker, TL (reprint author), Natl Res Council Canada, Herzberg Inst Astrophys, Dominion Radio Astrophys Observ, Penticton, BC V2A 6K3, Canada. NR 25 TC 28 Z9 28 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 DEC 20 PY 1999 VL 527 IS 2 BP 866 EP 878 DI 10.1086/308100 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 270XD UT WOS:000084561700033 ER PT J AU D'Alessio, P Calvet, N Hartmann, L Lizano, S Canto, J AF D'Alessio, P Calvet, N Hartmann, L Lizano, S Canto, J TI Accretion disks around young objects. II. Tests of well-mixed models with ISM dust SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; circumstellar matter; dust, extinction; stars : pre-main-sequence ID T-TAURI-STARS; MAIN-SEQUENCE STARS; SPECTRAL ENERGY-DISTRIBUTIONS; AURIGA MOLECULAR CLOUD; CIRCUMSTELLAR DISKS; VERTICAL STRUCTURE; IRAS OBSERVATIONS; STELLAR OBJECTS; MAGNETIC-FIELDS; SOLAR NEBULA AB We construct detailed Vertical structure models of irradiated accretion disks around T Tauri stars with interstellar medium dust uniformly mixed with gas. The dependence of the structure and emission properties on mass accretion rate, viscosity parameter, and disk radius is explored using these models. The theoretical spectral energy distributions (SEDs) and images for all inclinations are compared with observations of the entire population of classical T Tauri stars (CTTSs) and class I objects in Taurus. In particular, we find that the median near-infrared fluxes can be explained within the errors with the most recent values for the median accretion rates for CTTSs. We further show that the majority of the class I sources in Taurus cannot be class II sources viewed edge-on because they are too luminous and their colors would be consistent with disks seen only in a narrow range of inclinations. Our models appear to be too geometrically thick at large radii, as suggested by (1) larger far-infrared disk emission than in the typical SEDs of T Tauri stars, (2) wider dark dust lanes in the model images than in the images of HH 30 and HK Tau/c, and (3) a larger predicted number of stars extincted by edge-on disks than consistent with current surveys. The large thickness of the model is a consequence of the assumption that dust and gas are well mixed, suggesting that some degree of dust settling may be required to explain the observations. C1 Univ Nacl Autonoma Mexico, Inst Astron, Mexico City 04510, DF, Mexico. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP D'Alessio, P (reprint author), Univ Nacl Autonoma Mexico, Inst Astron, Apartado Postal 70-264, Mexico City 04510, DF, Mexico. NR 61 TC 338 Z9 338 U1 0 U2 7 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 DEC 20 PY 1999 VL 527 IS 2 BP 893 EP 909 DI 10.1086/308103 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 270XD UT WOS:000084561700035 ER PT J AU Schlegel, EM AF Schlegel, EM TI X-ray detection of SN1994W in NGC 4041? SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : spiral; supernovae : individual (SN 1994W); X-rays : galaxies ID II SUPERNOVAE; EMISSION AB Optical spectra of SN 1994W in NGC 4041 revealed the presence of a dense (N-e > 10(8) cm(-3)) circumstellar shell. An observation with the ROSAT High-Resolution Imager detected a source, with a luminosity of similar to 8 x 10(39) ergs s(-1), coincident with the position of SN 1994W to within 1".4. The positional coincidence plus the optical evidence for a dense circumstellar shell support the identification of the X-ray source as SN 1994W. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Schlegel, EM (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,Mail Stop 4, Cambridge, MA 02138 USA. NR 30 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 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1999 VL 527 IS 2 BP L85 EP L88 DI 10.1086/312408 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 270XE UT WOS:000084561800004 ER PT J AU Warren, HP Bookbinder, JA Forbes, TG Golub, L Hudson, HS Reeves, K Warshall, A AF Warren, HP Bookbinder, JA Forbes, TG Golub, L Hudson, HS Reeves, K Warshall, A TI Trace and Yohkoh observations of high-temperature plasma in a two-ribbon limb flare SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : activity; Sun : corona; Sun : flares ID X-RAY TELESCOPE; SOLAR-A MISSION AB The ability of the Transition Region and Coronal Explorer (TRACE) to image solar plasma over a wide range of temperatures (T-e similar to 10(4)-10(7) K) at high spatial resolution (0 ".5 pixels) makes it a unique instrument for observing solar flares. We present TRACE and Yohkoh observations of an M2.4 two-ribbon flare that began on 1999 July 25 at about 13:08 UT. We observe impulsive footpoint brightenings that are followed by the formation of high-temperature plasma (T-e greater than or similar to 10 MK) in the corona. After an interval of about 1300 s, cooler loops (T-e < 2 MK) form below the hot plasma. Thus, the evolution of the event supports the qualitative aspects of the standard reconnection model of solar flares. The TRACE and Yohkoh data show that the bulk of the flare emission is at or below 10 MK. The TRACE data are also consistent with the Yohkoh observations of hotter plasma (T-e similar to 15-20 MK) existing at the top of the arcade. The cooling time inferred from these observations is consistent with a hybrid cooling time based on thermal conduction and radiative cooling. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Solar Phys Res Corp, Tucson, AZ 85718 USA. Univ New Hampshire, Inst Study Earth Oceans & Space, Durham, NH 03824 USA. RP Warren, HP (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS 58, Cambridge, MA 02138 USA. RI Reeves, Katharine/P-9163-2014 NR 17 TC 45 Z9 45 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 DEC 20 PY 1999 VL 527 IS 2 BP L121 EP L124 DI 10.1086/312410 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 270XE UT WOS:000084561800013 ER PT J AU Zhang, QH Hunter, TR Sridharan, TK Cesaroni, R AF Zhang, QH Hunter, TR Sridharan, TK Cesaroni, R TI Shock-heated NH(3) in a molecular jet associated with a high-mass young star SO ASTROPHYSICAL JOURNAL LA English DT Article DE HII regions; ISM : clouds; ISM : individual (IRAS 20126+4104); ISM : kinematics and dynamics; masers; stars : formation; stars : pre-main-sequence ID AMMONIA; OUTFLOW; EMISSION; DISCOVERY; L1157; CLOUD AB We present the discovery of shock-excited NH(3) in a well-collimated jet associated with the extremely young high-mass star IRAS 20126+4104. The NH(3) (3, 3) and (4, 4) emission is dominated by three clumps along the SiO jet. At the end of the jet, there exists strong and broad (+/-10 km s(-1)) NH(3) (3, 3) emission. With typical brightness temperatures greater than 500 K, the overall emission indicates a weakly inverted population and appears in an are, consistent with the excitation by bow shocks. There are two bright spots in the NH(3) (3, 3) emission with brightness temperatures of approximately 2000 K. The narrow line width (1.5 km s(-1) FWHM), the small sizes (<0 ".3), and the unusually high brightness temperature of the features are indicative of maser emission. Our observations provide clear evidence that NH(3) (3, 3) masers are excited in shack regions in molecular outflows. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Osserv Astrofis Arcetri, I-50125 Florence, Italy. RP Zhang, QH (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. OI Zhang, Qizhou/0000-0003-2384-6589 NR 20 TC 29 Z9 29 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1999 VL 527 IS 2 BP L117 EP L120 DI 10.1086/312411 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 270XE UT WOS:000084561800012 ER PT J AU Baldwin, CC Johnson, GD AF Baldwin, CC Johnson, GD TI Paxton concilians: A new genus and species of pseudamine apogonid (Teleostei : Percoidei) from northwestern Australia: The sister group of the enigmatic Gymnapogon SO COPEIA LA English DT Article ID PACIFIC; FISHES AB Paxton concilians is described as a new genus and species of pseudamine apogonid from four specimens trawled off northwestern Australia. It differs most conspicuously from all other apogonids in having a continuous dorsal fin but shares with other members of the family certain specializations of the dorsal gill arches, last spinous dorsal fin pterygiophore, and cutaneous sensory system. We recognize two subfamilies of apogonids, the Apogoninae and Pseudaminae, and diagnose the latter on the basis of numerous derived features. We propose that Paxton be added as a fourth member of the Pseudaminae (with Gymnapogon, Pseudamia, and Pseudamiops) and provide strong evidence that Paxton is the sister group of Gymnapogon, a taxon whose phylogenetic position within the Apogonidae has never been well understood. C1 Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. RP Baldwin, CC (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. EM baldwin.carole@nmnh.si.edu NR 28 TC 8 Z9 9 U1 0 U2 2 PU AMER SOC ICHTHYOLOGISTS & HERPETOLOGISTS PI MIAMI PA MAUREEN DONNELLY, SECRETARY FLORIDA INT UNIV BIOLOGICAL SCIENCES, 11200 SW 8TH STREET, MIAMI, FL 33199 USA SN 0045-8511 EI 1938-5110 J9 COPEIA JI Copeia PD DEC 17 PY 1999 IS 4 BP 1050 EP 1071 DI 10.2307/1447980 PG 22 WC Zoology SC Zoology GA 269NH UT WOS:000084484100019 ER PT J AU Sweeney, MJ Harasewych, MG AF Sweeney, MJ Harasewych, MG TI Herald A. Rehder (1907-1996): biographical sketch and malacological contributions SO NAUTILUS LA English DT Biographical-Item C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Sweeney, MJ (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU BAILEY-MATTHEWS SHELL MUSEUM PI SANIBEL PA C/O DR JOSE H LEAL, ASSOCIATE/MANAGING EDITOR, 3075 SANIBEL-CAPTIVA RD, SANIBEL, FL 33957 USA SN 0028-1344 J9 NAUTILUS JI Nautilus PD DEC 16 PY 1999 VL 113 IS 4 BP 127 EP 150 PG 24 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA 270MU UT WOS:000084540300003 ER PT J AU Thompson, KV Monfort, SL AF Thompson, KV Monfort, SL TI Synchronization of oestrous cycles in sable antelope SO ANIMAL REPRODUCTION SCIENCE LA English DT Article DE antelope; oestrous synchronization; CIDR; fecal steroids ID ESTROUS SYNCHRONIZATION; ARTIFICIAL-INSEMINATION; HIPPOTRAGUS-NIGER; CIDR-B; ESTRUS; PROGESTERONE; OVULATION; CATTLE; DEER; INDUCTION AB Techniques for manipulating the oestrous cycle of sable antelope, Hippotragus niger, were evaluated in a captive population of 24 females maintained at the Smithsonian Institution's Conservation and Research Center in Front Royal, VA, USA. A secondary objective was to demonstrate the effectiveness of fecal steroid monitoring techniques as a non-invasive method of tracking experimental manipulations. Controlled Internal Drug Releasing (CIDR) devices designed for cattle (type B, reduced in length by 5 cm to fit the sable antelope's smaller reproductive tract) were more effective than CIDR devices designed for goats (type G) at delivering progesterone into circulation, and maintained serum progesterone at levels up to 86.1 +/- 7.8% of normal luteal concentrations in females whose spontaneous ovarian activity had been inhibited with melengestrol acetate. Serum progesterone and fecal progestagen measurements were highly correlated (P < 0.05). Synchronization treatments of prostaglandin (PG) F-2 alpha alone and in combination with modified CIDR-B devices (12-day insertion interval) were both effective in inducing synchronized ovulation, however the PGF(2 alpha)/modified CIDR-B treatment resulted in more precise synchrony and a shorter latency to ovulation than did PGF(2 alpha) alone. In a separate experiment to characterize the temporal relationship between synchronization treatment, behavioral oestrus and ovulation, onset of behavioral oestrus occurred 34.1 +/- 5.7 h following PGF(2 alpha)/modified CIDR-B treatment, Mean duration of the induced oestrus was 24.9 +/- 4.3 h. The first detectable rise in fecal progestagens occurred 5.1 +/- 1.0 and 4.1 +/- 1.0 days following PGF(2 alpha)/modified CIDR-B treatment in groups of females housed with and without an adult male, respectively, indicating that the presence of a male did not accelerate the onset of the induced cycle. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA 22630 USA. Univ Maryland, Coll Life Sci, Biol Sci Program, College Pk, MD 20742 USA. RP Thompson, KV (reprint author), Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, 1500 Remount Rd, Front Royal, VA 22630 USA. RI Thompson, Katerina/B-6146-2009 NR 30 TC 18 Z9 20 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4320 J9 ANIM REPROD SCI JI Anim. Reprod. Sci. PD DEC 15 PY 1999 VL 57 IS 3-4 BP 185 EP 197 DI 10.1016/S0378-4320(99)00061-5 PG 13 WC Agriculture, Dairy & Animal Science; Reproductive Biology SC Agriculture; Reproductive Biology GA 262KJ UT WOS:000084066100006 PM 10610038 ER PT J AU McCoy, TJ Lofgren, GE AF McCoy, TJ Lofgren, GE TI Crystallization of the Zagami shergottite: an experimental study SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article DE Zagami Meteorite; experimental studies; Mars; thermal history; crystallization; volcanism ID PARENT MAGMA; PETROGENESIS; METEORITES; INCLUSIONS; AMPHIBOLE; MANTLE; MELT AB The Zagami meteorite is a Martian basalt which exhibits multiple lithologies formed by fractional crystallization. While the rock has been widely studied petrologically, its genesis is poorly constrained from an experimental standpoint. Ongoing debates about the thermal history of this and other Martian meteorites affect our thinking about the environments in which they could have formed (e.g. lava flow vs. subsurface dike) and the types of rocks that surficial Mars exploration are likely to recover. We report on twelve equilibrium and nine dynamic crystallization experiments on a synthetic Zagami composition. Equilibrium experiments run at temperatures of 1260-1050 degrees C yield results similar to those of previous workers [E.H. Stolper, H.Y. McSween Jr., Geochim. Cosmochim. Acta 43 (1979) 1475-1498]. We observe crystallization of similar to 40 wt.% of magnesian pyroxenes comparable in composition to the most magnesian pyroxene in Zagami, even though petrologic studies suggest that this magnesian pyroxene comprises only similar to 20 wt.% of the meteorite. Experiments run at a range of f(O2) from IW to QFM + 3.9 log units suggest that crystallization of Zagami under conditions as reducing as QFM - 3 log units cannot explain this discrepancy. Resorption of pyroxenes may have been an important factor in explaining this discrepancy. The most likely explanation is that Zagami crystallized from a melt with a higher Fe/Mg ratio than used in this work. Dynamic crystallization experiments run at a range of cooling rates (0.5-10 degrees C/h) and nuclei densities (1-3 vol.%, produced by varying the peak temperature between 1230 degrees and 1250 degrees C) suggests that Zagami formed from a melt with a low nuclei density at a relatively slow cooling rate (<1 degrees C/h). Although these conditions produce a textural match for Zagami, important differences remain in the composition and chemical zoning of the experimental pyroxenes compared to Zagami. These differences might require either the use of a bulk composition with a higher Fe/Mg ratio or a slower (<0.1 degrees C/h) or multi-stage cooling rate. Published by Elsevier Science B.V. C1 Natl Museum Nat Hist, Dept Mineral Sci, Smithsonian Inst, Washington, DC 20560 USA. NASA, Lyndon B Johnson Space Ctr, Code SN4, Houston, TX 77058 USA. RP McCoy, TJ (reprint author), Natl Museum Nat Hist, Dept Mineral Sci, Smithsonian Inst, Washington, DC 20560 USA. NR 24 TC 32 Z9 32 U1 1 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0012-821X J9 EARTH PLANET SC LETT JI Earth Planet. Sci. Lett. PD DEC 15 PY 1999 VL 173 IS 4 BP 397 EP 411 DI 10.1016/S0012-821X(99)00241-1 PG 15 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 267BY UT WOS:000084335700003 ER PT J AU Rawitscher, GH Esry, BD Tiesinga, E Burke, JP Koltracht, I AF Rawitscher, GH Esry, BD Tiesinga, E Burke, JP Koltracht, I TI Comparison of numerical methods for the calculation of cold atom collisions SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID RADIAL SCHRODINGER-EQUATION; SPECTRUM AB Comparison between three different numerical techniques for solving a coupled channel Schrodinger equation is presented. The benchmark equation, which describes the collision between two ultracold atoms, consists of two channels, each containing the same diagonal Lennard-Jones potential, one of positive and the other of negative energy. The coupling potential is of an exponential form. The methods are (i) a recently developed spectral type integral equation method based on Chebyshev expansions, (ii) a finite element expansion, and (iii) a combination of an improved Numerov finite difference method and a Gordon method. The computing time and the accuracy of the resulting phase shift is found to be comparable for methods (i) and (ii), achieving an accuracy of ten significant figures with a double precision calculation. Method (iii) achieves seven significant figures. The scattering length and effective range are also obtained. (C) 1999 American Institute of Physics. [S0021-9606(99)01347-1]. C1 Univ Connecticut, Dept Phys, Storrs, CT 06268 USA. Univ Maryland, Dept Chem & Biochem, College Pk, MD 20742 USA. Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. Natl Inst Stand & Technol, Atom Phys Div, Gaithersburg, MD 20899 USA. Univ Colorado, Dept Phys, Boulder, CO 80309 USA. Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Univ Connecticut, Dept Math, Storrs, CT 06268 USA. RP Rawitscher, GH (reprint author), Univ Connecticut, Dept Phys, Storrs, CT 06268 USA. RI Esry, Brett/H-7511-2013 OI Esry, Brett/0000-0003-3207-8526 NR 34 TC 20 Z9 20 U1 0 U2 3 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 DEC 15 PY 1999 VL 111 IS 23 BP 10418 EP 10426 DI 10.1063/1.480431 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 260AY UT WOS:000083927200005 ER PT J AU Stauffer, JR Navascues, DBY Bouvier, J Morrison, HL Harding, P Luhman, KL Stanke, T McCaughrean, M Terndrup, DM Allen, L Assoaud, P AF Stauffer, JR Navascues, DBY Bouvier, J Morrison, HL Harding, P Luhman, KL Stanke, T McCaughrean, M Terndrup, DM Allen, L Assoaud, P TI Keck spectra of brown dwarf candidates and a precise determination of the lithium depletion boundary in the alpha Persei open cluster SO ASTROPHYSICAL JOURNAL LA English DT Article DE Hertzsprung-Russell diagram; open clusters and associations : individual (alpha Persei); stars : abundances; stars : low-mass, rown dwarfs ID LOW-MASS STARS; ROTATIONAL VELOCITIES; EVOLUTIONARY MODELS; FAINTEST PLEIADES; STANDARD STARS; MAIN-SEQUENCE; AGE; SPECTROSCOPY; MEMBERS; SYSTEM AB We have identified 27 candidate very low mass members of the relatively young alpha Persei open cluster from a 6 deg(2) CCD imaging survey. Based on their I magnitudes and the nominal age and distance to the cluster, these objects should have masses less than 0.1 M. if they are cluster members. We subsequently obtained intermediate-resolution spectra of 17 of these objects using the Keck II telescope and Low-Resolution Imaging Spectrograph (LRIS). We also obtained near-IR photometry for many of the stars. Our primary goal was to determine the location of the "lithium depletion boundary" and, hence, to derive a precise age for the cluster. Most of our program objects have radial velocities consistent with cluster membership, moderately strong Ha emission, and spectral types of M5.5 to M8, as expected from their (R-I)(C) colors. We detected lithium with equivalent widths greater than or equal to 0.4 Angstrom in five of the program objects. We have constructed a color-magnitude diagram for the faint end of the alpha Persei main sequence, including stars for which high signal-to-noise spectra in the region of the lithium lambda 6708 absorption line have been obtained. These data allow us to accurately determine the alpha Persei single-star lithium depletion boundary at M(I-C) = 11.47, M-bol = 11.42, (R-I)(C0) = 2.12, spectral type M6.0. By reference to theoretical evolutionary models, this converts fairly directly into an age for the alpha Persei cluster of 90 +/- 10 Myr. That age is considerably older than most previously quoted ages for the cluster but consistent with ages estimated from the upper main-sequence turnoff using recent models that include a moderate amount of convective core overshoot. At this age, the two faintest of our spectroscopically confirmed members should be substellar (i.e., brown dwarfs) according to theoretical models. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Max Planck Inst Astron, D-69117 Heidelberg, Germany. Univ Grenoble 1, Astrophys Lab, Observ Grenoble, F-38041 Grenoble, France. Case Western Reserve Univ, Dept Astron, Cleveland, OH 44106 USA. Univ Arizona, Steward Observ, Tucson, AZ 85726 USA. Inst Astrophys, D-14482 Potsdam, Germany. Ohio State Univ, Dept Astron, Columbus, OH 43210 USA. Int Space Univ, F-67400 Illkirch, France. RP Stauffer, JR (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. RI Barrado Navascues, David/C-1439-2017 OI Barrado Navascues, David/0000-0002-5971-9242 NR 41 TC 116 Z9 116 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 DEC 10 PY 1999 VL 527 IS 1 BP 219 EP 229 DI 10.1086/308069 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 265EA UT WOS:000084227300019 ER PT J AU Ballesteros-Paredes, J Hartmann, L Vazquez-Semadeni, E AF Ballesteros-Paredes, J Hartmann, L Vazquez-Semadeni, E TI Turbulent flow-driven molecular cloud formation: A solution to the post-T tauri problem? SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : clouds; ISM : evolution; stars : formation; stars : pre-main-sequence turbulence ID MAIN-SEQUENCE STARS; INTERSTELLAR-MEDIUM; SCALE STRUCTURE; DISK ACCRETION; H-I; COMPLEX; AURIGA; REGIONS; EVOLUTION; MODEL AB We suggest that molecular clouds can be formed on short timescales by compressions from large scale streams in the interstellar medium (ISM). In particular, we argue that in the Taurus-Auriga complex, with filaments of 10-20 x 2-5 pc, most have been formed by H I flows in less than or similar to 3 Myr, explaining the absence of post-T Tauri stars in the region with ages greater than or similar to 3 Myr. Observations in the 21 cm line of the H I "halos" around the Taurus molecular gas show many features (broad asymmetric profiles, velocity shifts of H I relative to (12)CO) predicted by our MHD numerical simulations, in which large-scale H I streams collide to produce dense filamentary structures. This rapid evolution is possible because the H I hows producing and disrupting the cloud have much higher velocities (5-10 km s(-1)) than are present in the molecular gas resulting from the colliding flows. The simulations suggest that such flows can occur from the global ISM turbulence without requiring a single triggering event such as a supernova explosion. C1 Univ Nacl Autonoma Mexico, Inst Astron, Mexico City 04510, DF, Mexico. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Ballesteros-Paredes, J (reprint author), Univ Nacl Autonoma Mexico, Inst Astron, Apdo Postal 70-264, Mexico City 04510, DF, Mexico. EM javier@astroscu.unam.mx NR 70 TC 194 Z9 194 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 1999 VL 527 IS 1 BP 285 EP 297 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 265EA UT WOS:000084227300026 ER PT J AU Di Matteo, T Allen, SW AF Di Matteo, T Allen, SW TI Hard X-ray emission from elliptical galaxies and its contribution to the X-ray background SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; galaxies : nuclei; X-rays : general ID ROSAT DEEP SURVEY; LOCKMAN FIELD; SPECTRUM; LUMINOSITY; ASCA; AGN AB We explore the implications of the discovery of hard, power-law X-ray sources in the spectra of nearby elliptical galaxies for the origin of the X-ray background (XRB). The spectra of these sources are consistent with models of thermal bremsstrahlung emission from low radiative efficiency accretion flows around central supermassive black holes and are unique in that they approximately match the spectrum of the hard XRB. If such sources, with luminosities consistent with those observed in nearby elliptical galaxies, are present in most early-type galaxies, then their integrated emission may contribute significantly to the XRB. These sources may also contribute to the hard source counts detected in deep X-ray surveys. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. RP Di Matteo, T (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 32 TC 7 Z9 7 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 DEC 10 PY 1999 VL 527 IS 1 BP L21 EP L24 DI 10.1086/312387 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 265GW UT WOS:000084235000006 ER PT J AU Kalkofen, W Ulmschneider, P AF Kalkofen, W Ulmschneider, P TI The dynamics and heating of the quiet solar chromosphere SO CURRENT SCIENCE LA English DT Article ID MAGNETIC-FLUX TUBES; LONGITUDINAL-TRANSVERSE WAVES; NETWORK BRIGHT POINTS; ATMOSPHERE; PROPAGATION; OSCILLATIONS; SUN AB The solar chromosphere can be characterized by two signatures: the spectroscopic signature is an emission spectrum for all radiation originating in the chromosphere; only NLTE effects in the cores of strong lines producing absorption features. And the dynamical signature is in the form of oscillations, with a period of 3 min in the nonmagnetic chromosphere and a period of 7 min in magnetic regions. The paper explains these signatures in terms of waves: The dynamics of the chromosphere is due to acoustic waves in the magnetic-field-free atmosphere, which produce K-2v bright points, and to kink and longitudinal waves in magnetic flux tubes, which produce network bright points. The heating of the chromosphere is caused by acoustic waves whose dissipation makes the kinetic temperature rise in the outward direction, producing the emission spectrum. As far as energy fluxes are concerned, the energy dissipated in chromospheric heating outweighs the energy visible in bright points by two orders of magnitude, The paper interprets the observed oscillation periods in the chromosphere as cutoff periods: for the 3 min period, as the cutoff period of acoustic waves in a nonmagnetic, stratified atmosphere; and for the 7-min period, as the cutoff period of kink waves in magnetic flux tubes for field strengths typical of the magnetic network. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Heidelberg Univ, Inst Theoret Astrophys, D-6900 Heidelberg, Germany. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM wolf@cfa.harvard.edu NR 39 TC 1 Z9 1 U1 0 U2 0 PU INDIAN ACAD SCIENCES PI BANGALORE PA C V RAMAN AVENUE, SADASHIVANAGAR, P B #8005, BANGALORE 560 080, INDIA SN 0011-3891 J9 CURR SCI INDIA JI Curr. Sci. PD DEC 10 PY 1999 VL 77 IS 11 BP 1496 EP 1502 PG 7 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 269FY UT WOS:000084467100030 ER PT J AU Killion, TW AF Killion, TW TI Mexican rural development and the plumed serpent: Technology and Maya cosmology in the tropical forest of Campeche, Mexico. SO AMERICAN ANTHROPOLOGIST LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Killion, TW (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU AMER ANTHROPOLOGICAL ASSOC PI ARLINGTON PA 4350 NORTH FAIRFAX DRIVE SUITE 640, ARLINGTON, VA 22203 USA SN 0002-7294 J9 AM ANTHROPOL JI Am. Anthropol. PD DEC PY 1999 VL 101 IS 4 BP 847 EP 848 DI 10.1525/aa.1999.101.4.847 PG 2 WC Anthropology SC Anthropology GA 298FW UT WOS:000086129500017 ER PT J AU Power, ML Heaney, RP Kalkwarf, HJ Pitkin, RM Repke, JT Tsang, RC Schulkin, J AF Power, ML Heaney, RP Kalkwarf, HJ Pitkin, RM Repke, JT Tsang, RC Schulkin, J TI The role of calcium in health and disease SO AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY LA English DT Review DE bone; hypertension; lactation; osteoporosis; pregnancy ID BONE-MINERAL DENSITY; RANDOMIZED CONTROLLED TRIAL; EXCESS DIETARY-PROTEIN; ADVERSELY AFFECT BONE; BLOOD-PRESSURE; VITAMIN-D; REGULATING HORMONES; URINARY CALCIUM; ABSORPTION EFFICIENCY; CELL-PROLIFERATION AB Skeletal fragility at the end of the life span (osteoporosis) is a major source of morbidity and mortality. Adequate calcium intake from childhood to the end of the life span is critical for the formation and retention of a healthy skeleton. High intakes of calcium and vitamin D potentiate the bone loss prevention effects of hormone replacement therapy in postmenopausal women. Pregnancy and lactation are not risk factors for skeletal fragility, although lactation is associated with a transient loss of bone that cannot be prevented by calcium supplementation. Low calcium intake has been implicated in the development of hypertension, colon cancer, and premenstrual syndrome, and it is associated with low intakes of many other nutrients. Encouragement of increased consumption of calcium-rich foods has the potential to be a cost-effective strategy for reducing fracture incidence later in life and for increasing patients' dietary quality and overall health. C1 Amer Coll Obstetricians & Gynecologists, Dept Res, Washington, DC 20024 USA. Smithsonian Inst, Natl Zool Pk, Washington, DC 20008 USA. Creighton Univ, Omaha, NE 68178 USA. Univ Cincinnati, Dept Pediat, Cincinnati, OH 45221 USA. Univ Calif Los Angeles, Dept Obstet & Gynecol, Los Angeles, CA 90024 USA. Univ Nebraska, Med Ctr, Dept Obstet & Gynecol, Omaha, NE USA. Childrens Hosp, Med Ctr, Div Gen & Community Pediat, Los Angeles, CA USA. RP Power, ML (reprint author), Amer Coll Obstetricians & Gynecologists, Dept Res, 409 12th St SW, Washington, DC 20024 USA. FU PHS HHS [MCJ 117016] NR 122 TC 48 Z9 54 U1 0 U2 7 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 DEC PY 1999 VL 181 IS 6 BP 1560 EP 1569 DI 10.1016/S0002-9378(99)70404-7 PG 10 WC Obstetrics & Gynecology SC Obstetrics & Gynecology GA 265VE UT WOS:000084265900054 PM 10601943 ER PT J AU Zotz, G AF Zotz, G TI What are backshoots good for? Seasonal changes in mineral, carbohydrate and water content of different organs of the epiphytic orchid, Dimerandra emarginata SO ANNALS OF BOTANY LA English DT Article DE Barro Colorado Island; Dimerandra emarginata; epiphytes; mineral nutrients; orchids; reproduction; resource allocation; total non-structural carbohydrates ID NITROGEN; LIMITATION; PLANTS; GROWTH; FOREST AB The epiphytic orchid, Dimerandra emarginata (G. Meyer) Hoehne, keeps older stems ('backshoots') after the attached foliage dies. I investigated seasonal changes in the water, carbohydrate and nutrient content of these leafless stems along with associated, connected organs for 1 year. Older stems significantly increase the water storage capacity of a plant, allowing it to tolerate long periods of drought. Reduction in total non-structural carbohydrates (TNC) at the beginning of the growing season indicated an important role of carbon stored in older stems for the re-initiation of vegetative growth after the dry season, while the lack of an increase in TNC before fruiting suggests no such role for reproduction. While seasonal fluctuations in water contents and TNC were pronounced, concentrations of nutrients (N, P, K) showed only small seasonal variation in all vegetative organs. Allocation of carbon and nutrients to developing fruits was rather high, exceeding, e.g. 20 % of the total plant pool of potassium. This large investment in fruits was derived from all vegetative organs. I conclude that persistent stems serve a crucial function in the water, carbon and nutrient relations of epiphytes such as D. emarginata, which live in habitats where access to water and key nutrients is often severely limited. (C) 1999 Annals of Botany Company. C1 Univ Wurzburg, Lehrstuhl Bot 2, D-97082 Wurzburg, Germany. Smithsonian Trop Res Inst, Balboa, Panama. RP Zotz, G (reprint author), Univ Wurzburg, Lehrstuhl Bot 2, D-97082 Wurzburg, Germany. NR 38 TC 14 Z9 14 U1 0 U2 4 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0305-7364 J9 ANN BOT-LONDON JI Ann. Bot. PD DEC PY 1999 VL 84 IS 6 BP 791 EP 798 DI 10.1006/anbo.1999.0983 PG 8 WC Plant Sciences SC Plant Sciences GA 266AQ UT WOS:000084278800013 ER PT J AU Kantor, YI Harasewych, MG AF Kantor, YI Harasewych, MG TI Rediscovery of the Antarctic species Sipho gaini Lamy, 1910 (Gastropoda : Neogastropoda) with remarks on its taxonomic position SO ANTARCTIC SCIENCE LA English DT Article DE bathyal; benthos; Conidae; Gastropoda; Mollusca; Scotia Plate; systematics AB Examination of the holotype of Sipho gaini Lamy, 1910, attributed by recent authors to the genus Chlanidota (Buccinulidae), revealed that this species belongs to the genus Belaturricula and is a senior synonym of Belaturricula antarctica Dell, 1990. A redescription oft he shell, anterior alimentary system, and radular morphology of Belaturricula gaini is provided. The genus Belaturricula is transferred to the family Conidae (sensu Taylor et al. 1993) on the basis of its radula, which is composed of hollow marginal teeth. The presence of a large shell, prominent operculum, acinous salivary glands, radular teeth with narrow bases in B. gaini, as well as the absence of buccal lips and rhyncodeal introvert, all indicate affinities with the conid subfamily Clathurellinae. Because the radula of Pontiothauma ergata Hedley(1916) is nearly indistinguishable from that of Belaturricula gaini, we reassign Hedley's species to the genus Belaturricula as Belaturricula ergata (Hedley, 1916). C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. Russian Acad Sci, AN Severtzov Inst Problems Evolut, Moscow 117071, Russia. RP Harasewych, MG (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RI Kantor, Yuri/D-5259-2014 OI Kantor, Yuri/0000-0002-3209-4940 NR 14 TC 0 Z9 2 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0954-1020 J9 ANTARCT SCI JI Antarct. Sci. PD DEC PY 1999 VL 11 IS 4 BP 430 EP 435 PG 6 WC Environmental Sciences; Geography, Physical; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Physical Geography; Geology GA 272KC UT WOS:000084648200008 ER PT J AU Grogin, NA Geller, MJ AF Grogin, NA Geller, MJ TI An imaging and spectroscopic survey of galaxies within prominent nearby voids. I. The sample and luminosity distribution SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : luminosity function, mass function; galaxies : photometry ID CAMPANAS REDSHIFT SURVEY; LARGE-SCALE STRUCTURE; COLD DARK-MATTER; ZWICKY MAGNITUDES; DWARF GALAXIES; FAINT GALAXIES; BOOTES; CFA; UNIVERSE; SLICE AB We study the optical properties of a large sample of galaxies in low-density regions of the nearby universe. We make a 5 h(-1) Mpc smoothed map of the galaxy density throughout the Center for Astrophysics Redshift Survey (CfA2) to identify galaxies within three prominent nearby "voids" with diameter greater than or similar to 30 h(-1) Mpc. We augment the CfA2 void galaxy sample with fainter galaxies found in the same regions from the more recent and deeper Century and Redshift surveys. We obtain B and R CCD images and high signal-to-noise long-slit spectra for the resulting sample of 149 void galaxies, as well as for an additional 131 galaxies on the periphery of these voids. Here we describe the photometry for the sample, including B isophotal magnitudes and B-R colors. For the 149 galaxies that lie in regions below the mean survey density, the luminosity functions in B and R are well fit by Schechter functions with respective parameters (alpha(B) = -0.5 +/- 0.3, B-* = -18.9 +/- 0.2) and (alpha(R) = -0.9 +/- 0.3, R-* = -20.4 +/- 0.3). The B luminosity function (LF) is consistent with typical survey LFs (e.g., the Southern Sky Redshift Survey), and the R LF is consistent with the Century Survey. The B and R LFs of 131 galaxies in the "void periphery"-regions between the mean density and twice the mean-have similar Schechter parameters. The CfA2 LF is inconsistent with both samples at the 3.5 a level. When we narrow our analysis to the 46 galaxies in regions below half the mean density, the LF is significantly steeper: alpha similar to -1.4 +/- 0.5. The typical survey LFs are inconsistent with this subsample at the similar to 2 sigma level. The B-R color distribution of galaxies in the lowest density regions is also shifted significantly (similar to 3 sigma) blueward of the higher density samples. The most luminous red galaxies (R less than or similar to -21) are absent from the lowest density regions at the 2.5 sigma level. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Grogin, NA (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 68 TC 52 Z9 52 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 DEC PY 1999 VL 118 IS 6 BP 2561 EP 2580 DI 10.1086/301126 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 274KY UT WOS:000084766100002 ER PT J AU Schlegel, EM Ryder, S Staveley-Smith, L Petre, R Colbert, E Dopita, M Campbell-Wilson, D AF Schlegel, EM Ryder, S Staveley-Smith, L Petre, R Colbert, E Dopita, M Campbell-Wilson, D TI Physical properties of the X-ray-luminous SN1978K in NGC 1313 from multiwavelength observations SO ASTRONOMICAL JOURNAL LA English DT Article DE supernova : individual (SN 1978K) ID SPIRAL GALAXY NGC-1313; H-II REGION; SUPERNOVA-REMNANTS; CIRCUMSTELLAR INTERACTION; SN 1978K; EMISSION; RADIO; SN-1987A; SN-1978K; ROSAT AB We update the light curves from the X-ray, optical, and radio bandpasses which we have assembled over the past decade and present two observations in the ultraviolet using the Hubble Space Telescope Faint Object Spectrograph. The HRI X-ray light curve is constant within the errors over the entire observation period. This behavior is confirmed in the ASCA GIS data obtained in 1993 and 1995. In the ultraviolet, we detected Ly alpha, the [Ne IV] 2422/2424 Angstrom doublet, the Mg II. doublet at 2800 Angstrom, and a line at approximately 3190 Angstrom that we attribute to He I 3187. Only the Mg II and He I lines are detected at SN 1978K's position. The optical light curve is formally constant within the errors, although a slight upward trend may be present. The radio light curve continues its steep decline. The longer time span of our radio observations compared to previous studies shows that SN 1978K is in the same class of highly X-ray and radio-luminous supernovae as SN 1986J and SN 1988Z. The [Ne IV] emission is spatially distant from the location of SN 1978K and originates in the preshocked matter. The Mg II doublet flux ratio implies the quantity of line optical depth times density of approximately 10(14) cm(-3) for its emission region. The emission site must lie in the shocked gas. C1 Harvard Smithsonian Ctr Astrophys, Smithsonian Astrophys Observ, High Energy Astrophys Div, Cambridge, MA 02138 USA. Joint Astron Ctr, Hilo, HI 96720 USA. CSIRO, Australia Telescope Natl Facil, Epping, NSW 2121, Australia. NASA, Goddard Space Flight Ctr, Xray Astrophys Grp, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Australian Natl Univ, Mt Stromlo & Siding Spring Observ, Weston, ACT 2611, Australia. Univ Sydney, Dept Astrophys, Sch Phys, Sydney, NSW 2006, Australia. RP Schlegel, EM (reprint author), Harvard Smithsonian Ctr Astrophys, Smithsonian Astrophys Observ, High Energy Astrophys Div, 60 Garden St, Cambridge, MA 02138 USA. RI Staveley-Smith, Lister/A-1683-2011; Dopita, Michael/P-5413-2014; OI Staveley-Smith, Lister/0000-0002-8057-0294; Dopita, Michael/0000-0003-0922-4986; Ryder, Stuart/0000-0003-4501-8100 NR 60 TC 26 Z9 26 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 DEC PY 1999 VL 118 IS 6 BP 2689 EP 2704 DI 10.1086/301145 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 274KY UT WOS:000084766100011 ER PT J AU Puzia, TH Kissler-Patig, M Brodie, JP Huchra, JP AF Puzia, TH Kissler-Patig, M Brodie, JP Huchra, JP TI The age difference between the globular cluster subpopulations in NGC 4472 SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : formation; galaxies : individual (NGC 4472); galaxies : star clusters; globular dusters : general ID ELLIPTIC GALAXIES; LUMINOSITY DISTRIBUTION; KECK SPECTROSCOPY; VIRGO ELLIPTICALS; PEAK BRIGHTNESS; BVI PHOTOMETRY; SYSTEMS; M87; CALIBRATION; REDDENINGS AB The age difference between the two main globular cluster subpopulations in the Virgo giant elliptical galaxy NGC 4472 (M49) has been determined using Hubble Space Telescope WFPC2 images in the F555W and F814W filters, accurate photometry has been obtained for several hundred globular clusters in each of the two main subpopulations, down to more than 1 mag below the turnover of their luminosity functions. This allows precise determinations of both the mean colors and the turnover magnitudes of the two main subpopulations. By comparing the data with various population synthesis models, the age-metallicity pairs that fit both the observed colors and magnitudes have been identified. The metal-poor and the metal-rich globular clusters are found to be coeval within the errors (similar to Gyr). If one accepts the validity of our assumptions, these errors are dominated by model uncertainties. A systematic error of up to 4 Gyr could affect this result if the blue and the red clusters have significantly different mass distributions. However, that one subpopulation is half as old as the other is excluded at the 99% confidence level. The different globular cluster populations are assumed to trace the galaxy's major star formation episodes. Consequently, the vast majority of globular clusters (and by implication the majority of stars) in NGC 4472 formed at high redshifts but by two distinct mechanisms or in two episodes. The distance to NGC 4472 is determined to be 15.8 +/- 0.8 Mpc, which is in excellent agreement with six of the seven Cepheid distances to Virgo Cluster spiral galaxies. This implies that the spiral and elliptical galaxies in the main body of Virgo are at the same distance. C1 Univ Sternwarte Bonn, D-53121 Bonn, Germany. Univ Calif Santa Cruz, Lick Observ, Santa Cruz, CA 95064 USA. European So Observ, D-85748 Garching, Germany. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Puzia, TH (reprint author), Univ Sternwarte Bonn, Hugel 71, D-53121 Bonn, Germany. NR 81 TC 87 Z9 87 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 DEC PY 1999 VL 118 IS 6 BP 2734 EP 2750 DI 10.1086/301141 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 274KY UT WOS:000084766100014 ER PT J AU Mennickent, RE Diaz, MP Arenas, J AF Mennickent, RE Diaz, MP Arenas, J TI Locating the emission line regions in polars - II. Doppler imaging of BL Hydri SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : individual : BL Hyi; stars : novae, cataclysmic variables; stars : fundamental parameters; stars : evolution; stars : binaries : general ID X-RAY-EMISSION; AM-HERCULIS; M-DWARFS; PHOTOMETRY; MODEL; HYI AB Phase-resolved spectroscopic observations of BL Hyi obtained during the high mass transfer state are presented. The H alpha, He I 5875 and He I 6678 emission line profiles are analyzed with the Doppler tomography technique. It is shown that these emissions arise from a single region in the accretion stream. No emission from the secondary star, either in the Hu: or in the; He I line, could be identified. The accretion column could not be detected on the tomographic reconstructions of the system. An orbital ephemeris based on the radial velocities of the Na I D emission line is derived, assuming a chromospheric origin in the secondary star. The spectroscopic observations provide a consistent picture of the accretion geometry in the system. Most of the optical emission line flux was found to be formed in a reservoir of low angular momentum gas filling a substantial fraction of the Roche lobe, Combining our results with literature data it was possible to constrain the absolute longitude of the magnetic axis in this classical polar. C1 Univ Concepcion, Fac Ciencias Fis & Matemat, Dept Fis, Concepcion, Chile. Univ Sao Paulo, Inst Astron & Geofis, BR-01006597 Sao Paulo, Brazil. Univ Keele, Dept Phys, Keele ST5 5BG, Staffs, England. RP Mennickent, RE (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM rmennick@stars.cfm.udec.cl; marcos@binary.iagusp.usp.br; jla@astro.keele.ac.uk RI diaz, marcos/I-7233-2013 NR 29 TC 6 Z9 6 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 DEC PY 1999 VL 352 IS 1 BP 167 EP 176 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 266AX UT WOS:000084279400030 ER PT J AU Mennickent, RE Sterken, C Gieren, W Unda, E AF Mennickent, RE Sterken, C Gieren, W Unda, E TI The dwarf nova RZ Leonis: photometric period, "anti-humps" and normal alpha disc SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : individual : RZ Leo; stars : novae, cataclysmic variables; stars : fundamental parameters; stars : evolution; stars : binaries : general ID FAINT CATACLYSMIC VARIABLES; ACCRETION DISKS; BINARY-SYSTEMS; ORBITAL PERIOD; IP-PEGASI; EVAPORATION; QUIESCENCE; OUTBURST; TIME; EVOLUTION AB We present results of differential photometry of the dwarf nova RZ Leonis spanning a 11-year baseline. The most striking feature of the light curve is a non-coherent periodic hump of variable amplitude. A seasonal time series analysis yields a photometric period of 0.(d)0756(12). In addition, low amplitude fluctuations of the mean magnitude in time scale of months are observed. We find that the hump's amplitude is anti-correlated with the star's mean magnitude and becomes "negative" (i.e. an absorption feature or "anti-hump") when the system is very faint. Secondary humps and "anti-humps" are also observed. The transition from "anti-humps" to fully developed humps occurs on a time scale of 70 days. We interprete the observations as a rapid response of the accretion disk to the increase of mass transfer rate. In this case we deduce a viscosity parameter alpha similar to 0.08, i.e. much larger than often claimed for WZ Sge-like stars. We note that the secondary star in RZ Leo is close to a main-sequence red dwarf and not a brown-dwarf like star as suggested for other long cycle-length SU UMa stars like WZ Sge and V592 Her. Our results indicate that large amplitude and long cycle length dwarf novae might not necessarily correspond to objects in the same evolutive stage. C1 Univ Concepcion, Dept Fis, Concepcion, Chile. Free Univ Brussels, B-1050 Brussels, Belgium. RP Mennickent, RE (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM rmennick@stars.cfm.udec.cl RI Unda-Sanzana, Eduardo/K-3592-2012 OI Unda-Sanzana, Eduardo/0000-0002-7514-8312 NR 48 TC 10 Z9 10 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 DEC PY 1999 VL 352 IS 1 BP 239 EP 247 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 266AX UT WOS:000084279400038 ER PT J AU Maggio, A Favata, F Negoro, H Brickhouse, NS Dupree, AK AF Maggio, A Favata, F Negoro, H Brickhouse, NS Dupree, AK TI ASCA X-ray observations of the super-metal-rich stars 30 Ari and eta Boo SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : coronae; stars : late-type; stars : abundances; stars : activity; X-rays : stars; stars : individual : 30 Ari; stars : individual : eta Boo ID SOLAR-TYPE STARS; MAIN-SEQUENCE; BETA-CETI; ABUNDANCES; ATMOSPHERES; EMISSION; SUN AB We present X-ray observations of two late-type stars, HR 764 (30 Ari B, F4V) and HR 5235 (eta Boo, G0IV), with photospheric metal abundances about twice the solar value. We have derived the coronal temperatures and metallicities of these stars, and compared them with those of other stellar X-ray sources with solar or sub-solar photospheric composition, already observed with ROSAT and ASCA. The X-ray spectra of the two targets can be fitted with isothermal models yielding temperatures of 6.2 MK and 3.5 MK, and X-ray luminosities log L-x = 29.6 and 28.1 erg s(-1), for HR 764 and HR 5235 respectively. The best-fit model for HR 764, including a gaussian component which accounts for Fe XVII line emission from highly excited states, yields for its corona a solar (photospheric) iron abundance, while the best-fit iron abundance for HR 5235 is about half solar; however, in both cases, the uncertainties do not allow excluding values consistent with photospheric metallicities. Instead, the data indicate significant overabundances of Mg and Si by factors 2-3 with respect to the Fe abundance, and suggest low O/Fe abundance ratios. We conclude that these two super-metal-rich stars appear to have coronal properties similar to those of other F and G main-sequence stars with "normal" photospheric abundances: in particular, HR 764 looks similar to the Hyades F stars, while the coronal temperature, luminosity and abundances of HR 5235 are similar to those of other field G dwarfs slightly younger than the Sun. The systematic pattern of O, Mg, Si, and Fe coronal abundances generally found for solar-type stars observed with ASCA is puzzling, because it does not appear related either to the photospheric composition or to the activity level. C1 Osservatorio Astron Palermo GS Vaiana, I-90134 Palermo, Italy. European Space Agcy, ESTEC, Dept Space Sci, Div Astrophys, NL-2200 AG Noordwijk, Netherlands. Inst Phys & Chem Res, Wako, Saitama 3510198, Japan. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Maggio, A (reprint author), Osservatorio Astron Palermo GS Vaiana, Palazzo Normanni, I-90134 Palermo, Italy. EM amaggio@oapa.astropa.unipa.it RI Maggio, Antonio/P-5700-2015 OI Maggio, Antonio/0000-0001-5154-6108 NR 35 TC 2 Z9 2 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 DEC PY 1999 VL 352 IS 1 BP 248 EP 256 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 266AX UT WOS:000084279400039 ER PT J AU Dubinski, J Mihos, JC Hernquist, L AF Dubinski, J Mihos, JC Hernquist, L TI Constraining dark halo potentials with tidal tails SO ASTROPHYSICAL JOURNAL LA English DT Article DE dark matter; galaxies : halos; galaxies : interactions; galaxies : kinematics and dynamics; galaxies : structure ID SPIRAL GALAXIES; INTERACTING GALAXIES; ROTATION CURVES; MATTER HALOS; MERGER REMNANTS; MILKY-WAY; MASS; DISKS; COLD; PROGENITORS AB We present an extensive parameter survey of the influence of halo mass profiles on the development of tidal tails in interacting disk galaxies. We model the galaxies using a fixed exponential disk with a central bulge and vary the halo potential over a range of parameters using both the Hernquist and Navarro, Frenk, & White mass distributions, probing the effect of the halo mass, extent, and concentration. We examine the consistency of the results against both observational and theoretical constraints on halo profiles and comment on the failures and weaknesses of different models. A galaxy with a rising or flat rotation curve dominated by the halo is inhibited from forming a tidal tail unless the halo is abruptly cut off just beyond the disk edge. Conversely, models with declining rotation curves-resulting either from compact, low-mass halos or from massive disk components in low-concentration dark halos-produce tidal tails very similar to those observed in well-studied interacting systems. As argued by Springel & White, a unifying, quantitative relation for all cases is that the ratio of the escape velocity to the circular velocity at around the solar radius must be nu(e)/nu(c) less than or equal to 2.5 for tidal tails to be produced. The galaxy models that appear to fit most of the observational constraints are those that have disk-dominated rotation curves and low-concentration halos. We discuss our results in a cosmological context using recent studies that link halo properties to cosmological models. C1 Univ Toronto, Canadian Inst Theoret Astrophys, Toronto, ON M5S 3H8, Canada. Case Western Reserve Univ, Dept Astron, Cleveland, OH 44106 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Dubinski, J (reprint author), Univ Toronto, Canadian Inst Theoret Astrophys, 60 St George St, Toronto, ON M5S 3H8, Canada. NR 71 TC 81 Z9 82 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 DEC 1 PY 1999 VL 526 IS 2 BP 607 EP 622 DI 10.1086/308024 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 263GF UT WOS:000084116500007 ER PT J AU Medvedev, MV Loeb, A AF Medvedev, MV Loeb, A TI Generation of magnetic fields in the relativistic shock of gamma-ray burst sources SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; instabilities; magnetic fields; polarization; radiation mechanisms : nonthermal; shock waves ID COSMOLOGICAL FIREBALL MODEL; WEIBEL INSTABILITY; RADIO AFTERGLOW; PLASMA; SCINTILLATION; TIMESCALES; SPECTRUM; PULSARS; STARS; SIZE AB We show that the relativistic two-stream instability can naturally generate strong magnetic fields with 10(-5)-10(-1) of the equipartition energy density, in the collisionless shocks of gamma-ray burst (GRB) sources. The generated fields are parallel to the shock front and fluctuate on the very short scale of the plasma skin depth. The synchrotron radiation emitted from the limb-brightened source image is linearly polarized in the radial direction relative to the source center. Although the net polarization vanishes under circular symmetry, GRB sources should exhibit polarization scintillations as their radio afterglow radiation gets scattered by the Galactic interstellar medium. Detection of polarization scintillations could therefore test the above mechanism for magnetic field generation. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. IV Kurchatov Atom Energy Inst, RRC, Inst Nucl Fus, Moscow 123182, Russia. RP Medvedev, MV (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 48 TC 541 Z9 543 U1 3 U2 20 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 DEC 1 PY 1999 VL 526 IS 2 BP 697 EP 706 DI 10.1086/308038 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 263GF UT WOS:000084116500014 ER PT J AU Lee, CW Myers, PC Tafalla, M AF Lee, CW Myers, PC Tafalla, M TI A survey of infall motions toward starless cores. I. CS (2-1) and N2H+ (1-0) observations SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : globules; ISM : kinematics and dynamics; ISM : molecules; stars : formation ID CLOUD CORES; SUBMILLIMETER AB We present the first results of a survey of 220 starless cores selected primarily by their optical obscuration and observed in CS (2-1), N2H+ (1-0), and (CO)-O-18 (1-0) using the Northeast Radio Observatory Corporation (NEROC) Haystack 37 m telescope. We have detected 163 out of 196 sources observed in CS, 72 out of 142 in N2H+, and 30 out of 30 in (CO)-O-18. In total, 69 sources were detected in both CS and N2H+. The isolated component of the N2H+ (1-0) spectrum (F-1 F = 0, 1-1, 2) usually shows a weak symmetric profile that is optically thin. In contrast, a significant fraction of the CS spectra show non-Gaussian shapes, which we interpret as arising from a combination of self-absorption due to lower excitation gas in the core front and kinematics in the core. The distribution of the normalized velocity difference (delta V-CS) between the CS and N2H+ peaks appears significantly skewed to the blue (delta V-CS < 0), as was found in a similar study of dense cores with embedded young stellar objects (YSOs). The incidence of sources with blue asymmetry tends to increase as the total optical depth or the integrated intensity of the N2H+ line increases. This overabundance of "blue" over "red" sources suggests that inward motions are a significant feature of starless cores. We identify seven strong infall candidates and 10 probable infall candidates. Their typical inward speeds are subsonic, approximately 0.04-0.1 km s(-1), so they contain "thermal" infall motions, unlike the faster inward speeds associated with most YSOs. We discuss the importance of the choice of a consistent set of line frequencies when using the velocity shift between an optically thick and a thin line as a tracer of infall, and show how the results of the survey depend on that frequency choice. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Korea Astron Observ, Taeduk Radio Astron Observ, Yusung Ku, Taejon 305348, South Korea. Observ Astron Nacl, E-28800 Alcala De Henares, Madrid, Spain. RP Lee, CW (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS 42, Cambridge, MA 02138 USA. NR 27 TC 141 Z9 142 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 DEC 1 PY 1999 VL 526 IS 2 BP 788 EP 805 DI 10.1086/308027 PN 1 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 263GF UT WOS:000084116500022 ER PT J AU Butler, RP Marcy, GW Fischer, DA Brown, TM Contos, AR Korzennik, SG Nisenson, P Noyes, RW AF Butler, RP Marcy, GW Fischer, DA Brown, TM Contos, AR Korzennik, SG Nisenson, P Noyes, RW TI Evidence for multiple companions to upsilon andromedae SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : spectroscopic; planetary systems; stars : individual to (upsilon Andromedae) ID RHO-CORONAE-BOREALIS; GIANT PLANETS; RADIAL-VELOCITY; TAU-BOOTIS; ORBITAL MIGRATION; STARS; 51-PEGASI; SYSTEMS; DISK; EVOLUTION AB The bright F8 V star upsilon Andromedae was previously reported to have a 4.6 day Doppler velocity periodicity, consistent with having a Jupiter-mass companion orbiting at 0.059 AU. Follow-up observations by both the Lick and Advanced Fiber-Optic Echelle spectrometer (AFOE) planet survey programs confirm this periodicity and reveal additional periodicities at 241 and 1267 days. These periodicities are consistent with Keplerian orbital motion and imply two additional companions orbiting at 0.83 and 2.5 AU, with minimum (M sin i) masses of 2.0 and 4.6 M-JUP, respectively. Non-Keplerian explanations for the observed Doppler velocity variations, including radial and nonradial pulsations, rotational modulation of surface features, and stellar magnetic cycles, are examined. These explanations seem unlikely based on the observed photometric and chromospheric stability of the star. This putative three-planet system is found to be dynamically stable by both analytic techniques and numerical simulations. The outer two companions both reside in eccentric orbits, as do all nine known extrasolar planet candidates in distant orbits. If real, this multiple-planet system is the first around a main-sequence star, and its study should offer insights into planet formation, planet-planet interactions, and the observed eccentricities of planetary orbits. C1 Anglo Australian Observ, Epping, NSW 1710, Australia. San Francisco State Univ, Dept Phys & Astron, San Francisco, CA 94132 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Natl Ctr Atmospher Res, High Altitude Observ, Boulder, CO 80307 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Butler, RP (reprint author), Carnegie Inst Washington, Dept Terr Magnetism, 5241 Broad Branch Rd NW, Washington, DC 20015 USA. RI Butler, Robert/B-1125-2009 NR 55 TC 228 Z9 231 U1 1 U2 4 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 DEC 1 PY 1999 VL 526 IS 2 BP 916 EP 927 DI 10.1086/308035 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 263GF UT WOS:000084116500032 ER PT J AU Di Matteo, T Psaltis, D AF Di Matteo, T Psaltis, D TI Quasi-periodic variability and the inner radii of thin accretion disks in galactic black hole systems SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; black hole physics; X-rays : stars ID X-RAY BINARIES; HIGH STATE; OSCILLATIONS; CANDIDATES AB We calculate upper bounds on the inner radii of geometrically thin accretion disks in galactic black hole systems by relating their rapid variability properties to those of neutron stars. We infer that the inner disk radii do not exhibit large excursions between different spectral states, in contrast with the concept that the disk retreats significantly during the soft-to-hard-state transition. We find that, in the hard state, the accretion disks extend down to radii less than or similar to 6-25 GM/c(2) and discuss the implications of our results for models of black hole X-ray spectra. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Di Matteo, T (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 42 TC 35 Z9 35 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 DEC 1 PY 1999 VL 526 IS 2 BP L101 EP L104 DI 10.1086/312369 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 263GG UT WOS:000084116600012 ER PT J AU Maraschi, L Fossati, G Tavecchio, E Chiappetti, L Celotti, A Ghisellini, G Grandi, P Pian, E Tagliaferri, G Treves, A Breslin, AC Buckley, JH Carter-Lewis, DA Catanese, M Cawley, MF Fegan, DJ Fegan, S Finley, J Gaidos, J Hall, T Hillas, AM Krennrich, F Lessard, RW Masterson, C Moriarty, P Quinn, J Rose, J Samuelson, F Weekes, TC Urry, CM Takahashi, T AF Maraschi, L Fossati, G Tavecchio, E Chiappetti, L Celotti, A Ghisellini, G Grandi, P Pian, E Tagliaferri, G Treves, A Breslin, AC Buckley, JH Carter-Lewis, DA Catanese, M Cawley, MF Fegan, DJ Fegan, S Finley, J Gaidos, J Hall, T Hillas, AM Krennrich, F Lessard, RW Masterson, C Moriarty, P Quinn, J Rose, J Samuelson, F Weekes, TC Urry, CM Takahashi, T TI Simultaneous X-ray and TeV observations of a rapid flare from markarian 421 SO ASTROPHYSICAL JOURNAL LA English DT Article DE BL lacertae objects : individual (markarian 421); galaxies : active; galaxies : jets; gamma rays : observations; X-rays : galaxies ID LACERTAE OBJECT MARKARIAN-421; SPECTRAL ENERGY-DISTRIBUTIONS; ACTIVE GALAXY MARKARIAN-421; MULTIWAVELENGTH OBSERVATIONS; BLAZARS; VARIABILITY; EMISSION; PHOTONS; BURSTS; JETS AB Mrk 421 was observed for about 2 days with BeppoSAX in 1998 April as part of a worldwide multiwavelength campaign. A large, well-defined flare was observed in X-rays. The same flare was observed simultaneously at TeV energies by the Whipple Observatory gamma-ray telescope. These data provide (1) the first evidence that the X-ray and TeV intensities are well correlated on timescales of hours and (2) the first exactly simultaneous X-ray and TeV spectra. The results imply that the X-ray and TeV photons derive from the same region and from the same population of relativistic electrons. 'The physical parameters deduced from a homogeneous synchrotron self-Compton model for the spectral energy distribution yield electron cooling times close to the observed variability timescales. C1 Osservatorio Astron Brera, I-20121 Milan, Italy. Univ Calif San Diego, Ctr Astrophys & Space Sci, La Jolla, CA 92093 USA. CNR, Inst Fis Cosm, I-21133 Milan, Italy. Scuola Int Super Studi Avanzati, ISAS, I-34014 Trieste, Italy. CNR, Ist Astrofis Spaziale, I-00133 Rome, Italy. CNR, Ist Tecnol & Studio Radiazioni Extraterrestri, I-40129 Bologna, Italy. Univ Insubria, I-22100 Como, Italy. Univ Coll Dublin, Expt Phys Dept, Dublin 4, Ireland. Washington Univ, Dept Phys, St Louis, MO 63130 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Natl Univ Ireland, Dept Phys, Maynooth, Kildare, Ireland. Harvard Smithsonian Ctr Astrophys, Fred Lawrence Whipple Observ, Amado, AZ 85645 USA. Purdue Univ, Dept Phys, W Lafayette, IN 47907 USA. Univ Leeds, Dept Phys, Leeds LS2 9JT, W Yorkshire, England. Galway Mayo Inst Technol, Sch Sci, Galway, Ireland. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Inst Space & Astronaut Sci, Kanagawa 2298510, Japan. RP Maraschi, L (reprint author), Osservatorio Astron Brera, Via Brera 28, I-20121 Milan, Italy. RI Fossati, Giovanni/A-5841-2009; Urry, Claudia/G-7381-2011 OI Urry, Claudia/0000-0002-0745-9792 NR 43 TC 90 Z9 90 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 DEC 1 PY 1999 VL 526 IS 2 BP L81 EP L84 DI 10.1086/312370 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 263GG UT WOS:000084116600007 ER PT J AU Megeath, ST Tieftrunk, AR AF Megeath, ST Tieftrunk, AR TI The detection of outflows in the infrared-quiet molecular core NGC 6334/I(North) SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : individual (NGC 6334); ISM : jets and outflows; ISM : molecules; stars : formation ID STAR-FORMATION; NGC-6334; MASERS; EMISSION; REGIONS AB We find strong evidence for outflows originating in the dense molecular core NGC 6334/I(North): a 1000 M. molecular core distinguished by its lack of H II regions and mid-IR emission. New observations were obtained of the SiO (2 --> 1) and (5 --> 4) lines with the SEST 15 m telescope and of the H-2 (nu = 1 --> 0) S(1) line with the ESO 2.2 m telescope. The line profiles of the SiO transitions show broad wings extending from -50 to 40 km s(-1), and spatial maps of the line-wing emission exhibit a bipolar morphology with the peaks of the red and blue wing separated by 30 ". The estimated mass-loss rate of the outflow is comparable to those for young intermediate- to high-mass stars. The near-IR images show eight knots of H-2 emission. Five of the knots form a linear chain that is displaced from the axis of the SiO outflow; these knots may trace shock-excited gas along the path of a second, highly collimated outflow. We propose that NGC 6334/I(North) is a rare example of a molecular core in an early stage of cluster formation. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Cologne, Inst Phys 1, Kolner Observ Submillimeter Astron, D-50937 Cologne, Germany. RP Megeath, ST (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 29 TC 16 Z9 16 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 DEC 1 PY 1999 VL 526 IS 2 BP L113 EP L116 DI 10.1086/312374 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 263GG UT WOS:000084116600015 ER PT J AU McRae, SB Amos, W AF McRae, SB Amos, W TI Can incest within cooperative breeding groups be detected using DNA fingerprinting? SO BEHAVIORAL ECOLOGY AND SOCIOBIOLOGY LA English DT Article ID INBREEDING AVOIDANCE; GENETIC-ANALYSIS; PATERNITY; MONOGAMY; REPRODUCTION; WOODPECKER; FAMILY; WRENS; SKEW C1 Dept Zool, Cambridge CB2 3EJ, England. RP McRae, SB (reprint author), Smithsonian Trop Res Inst, Apartado 2072, Balboa, Panama. NR 30 TC 11 Z9 11 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0340-5443 J9 BEHAV ECOL SOCIOBIOL JI Behav. Ecol. Sociobiol. PD DEC PY 1999 VL 47 IS 1-2 BP 104 EP 107 DI 10.1007/s002650050655 PG 4 WC Behavioral Sciences; Ecology; Zoology SC Behavioral Sciences; Environmental Sciences & Ecology; Zoology GA 266BZ UT WOS:000084281900013 ER PT J AU Lovejoy, TE AF Lovejoy, TE TI Ecology and management of fragmented tropical landscapes - Preface SO BIOLOGICAL CONSERVATION LA English DT Editorial Material C1 Smithsonian Inst, Washington, DC 20560 USA. RP Lovejoy, TE (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 0 TC 1 Z9 1 U1 1 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0006-3207 J9 BIOL CONSERV JI Biol. Conserv. PD DEC PY 1999 VL 91 IS 2-3 BP 99 EP 99 DI 10.1016/S0006-3207(99)00130-5 PG 1 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 252ZA UT WOS:000083531100001 ER PT J AU Laurance, WF AF Laurance, WF TI Ecology and management of fragmented tropical landscapes - Introduction and synthesis SO BIOLOGICAL CONSERVATION LA English DT Editorial Material ID FOREST FRAGMENTATION; EXTINCTION; RESPONSES; AMAZON C1 Natl Inst Res Amazon, INPA, Biol Dynam Forest Fragments Project, BR-69011970 Manaus, Amazonas, Brazil. Smithsonian Inst, Natl Museum Nat Hist, Biodivers Program, Washington, DC 20560 USA. RP Laurance, WF (reprint author), Natl Inst Res Amazon, INPA, Biol Dynam Forest Fragments Project, CP 478, BR-69011970 Manaus, Amazonas, Brazil. RI Laurance, William/B-2709-2012 NR 22 TC 28 Z9 32 U1 1 U2 8 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0006-3207 J9 BIOL CONSERV JI Biol. Conserv. PD DEC PY 1999 VL 91 IS 2-3 BP 101 EP 107 DI 10.1016/S0006-3207(99)00087-7 PG 7 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 252ZA UT WOS:000083531100002 ER PT J AU Laurance, WF AF Laurance, WF TI Reflections on the tropical deforestation crisis SO BIOLOGICAL CONSERVATION LA English DT Article; Proceedings Paper CT 1998 Symposium on the Ecology and Management of Fragmented Tropical Landscapes CY 1998 CL SYDNEY, AUSTRALIA DE biodiversity; government policy; habitat fragmentation; human overpopulation; logging; rainforests; trade liberalization; tropical deforestation ID CARBON-DIOXIDE; CLIMATE-CHANGE; RAIN-FORESTS; MANAGEMENT; AMAZONIA; ECOLOGY; CONSERVATION; MAHOGANY; AMERICA; LEAVE AB Tropical forests do far more than sustain biodiversity; they are homes to indigenous peoples, pharmacopeias of natural products, and provide vital ecosystem services, such as flood amelioration and soil conservation. At regional and global scales, tropical forests also have a major influence on carbon storage and climate. I highlight these benefits, then assess the pattern and pace of tropical forest destruction in the Americas, Asia, and Africa. Asia emerges as the most immediate concern, because it has less surviving forest than the other two regions and higher relative rates of deforestation and logging. At regional and national levels, however, there is enormous variation in rates of forest loss. I discuss some factors that tend to promote forest conversion in developing countries, and propose that four - human population pressure. weak government institutions and poor policies, increasing trade liberalization, and industrial logging - are emerging as key drivers of forest destruction. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Natl Inst Res Amazon, INPA, Biol Dynam Forest Fragments Project, BR-69011970 Manaus, Amazonas, Brazil. Smithsonian Inst, Natl Museum Nat Hist, Biodivers Program, Washington, DC 20560 USA. RP Laurance, WF (reprint author), Natl Inst Res Amazon, INPA, Biol Dynam Forest Fragments Project, CP 478, BR-69011970 Manaus, Amazonas, Brazil. RI Laurance, William/B-2709-2012 NR 105 TC 244 Z9 259 U1 26 U2 151 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0006-3207 J9 BIOL CONSERV JI Biol. Conserv. PD DEC PY 1999 VL 91 IS 2-3 BP 109 EP 117 DI 10.1016/S0006-3207(99)00088-9 PG 9 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 252ZA UT WOS:000083531100003 ER PT J AU Mesquita, RCG Delamonica, P Laurance, WF AF Mesquita, RCG Delamonica, P Laurance, WF TI Effect of surrounding vegetation on edge-related tree mortality in Amazonian forest fragments SO BIOLOGICAL CONSERVATION LA English DT Article; Proceedings Paper CT 1998 Symposium on the Ecology and Management of Fragmented Tropical Landscapes CY 1998 CL SYDNEY, AUSTRALIA DE Amazon rainforest; edge effects; forest dynamics; forest fragmentation; landscape ecology; matrix type; secondary forest; tree mortality ID BRAZILIAN AMAZON; COMMUNITIES; MAMMALS AB Little is known about factors that cause spatial variability in edge effects, the diverse physical and biotic changes associated with the abrupt boundaries of fragmented forests. We examined the influence of three types of surrounding vegetation (cattle pastures. Cecropia-dominated regrowth, and Vismia-dominated regrowth). on edge-related tree mortality in Amazonian rainforest fragments. An ANCOVA revealed that the type of surrounding vegetation and distance to edge both had significant effects on tree mortality. Differences among vegetation types were greatest within 0-20 m of fragment edges; with edges bordered by cattle pastures having higher mortality than those bordered by Cecropia- and Vismia-dominated regrowth. Edge effects appeared to penetrate further into pasture-bordered edges (ca. 60-100 m) than those bordered by regrowth forest (ca. 40-60 m), but this difference was nonsignificant because of considerable patchiness in tree mortality. Overall, our results suggest that edge effects in forest fragments are significantly influenced by the structure of surrounding vegetation, and that the capacity of different regrowth forests to buffer edge effects can be predicted from the growth form and stand features of the dominant tree species. Management of surrounding vegetation can ameliorate the negative effects of edge creation on small forest fragments. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Natl Inst Res Amazon, INPA, Biol Dynam Forest Fragments Project, BR-69011970 Manaus, Amazonas, Brazil. Smithsonian Inst, Natl Museum Nat Hist, Biodivers Program, Washington, DC 20560 USA. RP Mesquita, RCG (reprint author), Natl Inst Res Amazon, INPA, Biol Dynam Forest Fragments Project, CP 478, BR-69011970 Manaus, Amazonas, Brazil. RI Laurance, William/B-2709-2012 NR 40 TC 140 Z9 154 U1 6 U2 25 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0006-3207 J9 BIOL CONSERV JI Biol. Conserv. PD DEC PY 1999 VL 91 IS 2-3 BP 129 EP 134 DI 10.1016/S0006-3207(99)00086-5 PG 6 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 252ZA UT WOS:000083531100005 ER PT J AU Laurance, SG Laurance, WF AF Laurance, SG Laurance, WF TI Tropical wildlife corridors: use of linear rainforest remnants by arboreal mammals SO BIOLOGICAL CONSERVATION LA English DT Article; Proceedings Paper CT 1998 Symposium on the Ecology and Management of Fragmented Tropical Landscapes CY 1998 CL SYDNEY, AUSTRALIA DE arboreal mammals; Australia; habitat fragmentation; marsupials; North Queensland; rainforest; tropical forest; wildlife corridors ID RAIN-FOREST FRAGMENTATION; QUEENSLAND; MARSUPIALS; RESPONSES; EXTINCTION; AUSTRALIA; DESIGN AB In fragmented landscapes, linear forest remnants have the potential to provide habitat and movement corridors for wildlife. We used systematic spotlighting surveys to sample arboreal mammals in 36 linear rainforest remnants in tropical Queensland, Australia. The effects of corridor width, height, isolation, elevation, and floristic composition on mammals were assessed with multiple regression models. Six species were recorded during 108 surveys. The most vulnerable species, the lemuroid ringtail possum (Hemibelideus lemuroides), was found only in remnants comprised of primary rainforest that were linked to large tracts of continuous forest. Two other species, the Herbert River ringtail possum (Pseudochirulus herbertensis) and striped possum (Dactylopsila trivirgata), also favored corridors that were linked to forest tracts or fragments, with the former favoring high-diversity forest (primary forest or mixed regrowth) over low-diversity (Acacia) regrowth. Three other species, the coppery brushtail possum (Trichosurus vulpecula), green ringtail possum (Pseudochirops archeri), and Lumholtz's tree-kangaroo (Dendrolagus lumholtzi), occurred in both isolated and non-isolated remnants and both primary forest and regrowth th. Our findings suggest that linear forest remnants that are floristically diverse (not Acacia-dominated regrowth) and at least 30-40 m width can function as habitat and probably movement corridors for most arboreal mammals in this region. The lemuroid ringtail, however, apparently. requires corridors of primary rainforest of at least 200 m in width. Because the lemuroid ringtail is highly vulnerable to forest fragmentation, faunal corridors in this region should be designed wherever possible to meet its ecological requirements. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Natl Inst Res Amaxon, Biol Dynam Forest Fragments Project, INPA, BR-69011970 Manaus, Amazonas, Brazil. Univ New England, Dept Ecosyst Management, Armidale, NSW 2350, Australia. Smithsonian Inst, Natl Museum Nat Hist, Biodivers Program, Washington, DC 20560 USA. RP Laurance, SG (reprint author), INPA Ecol, Biol Dynam Forest Fragments Project, CP 478, BR-69011970 Manaus, Amazonas, Brazil. RI Laurance, William/B-2709-2012; Laurance, Susan/G-6021-2011 OI Laurance, Susan/0000-0002-2831-2933 NR 49 TC 70 Z9 79 U1 4 U2 39 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0006-3207 J9 BIOL CONSERV JI Biol. Conserv. PD DEC PY 1999 VL 91 IS 2-3 BP 231 EP 239 DI 10.1016/S0006-3207(99)00077-4 PG 9 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 252ZA UT WOS:000083531100016 ER PT J AU Urquhart, GR AF Urquhart, GR TI Long-term persistence of Raphia taedigera Mart. swamps in Nicaragua SO BIOTROPICA LA English DT Article DE Arecaceae; Central America; long-term studies; Nicaragua; paleoecology; palms; palynology; Raphia taedigera Mart.; swamps AB The palm Raphia taedigera Mart. forms vast, monodominant swamps in Central and South America, but very little is known about the ecology and natural history of these ecosystems. Debate surrounds the issue whether R. taedigera swamps are early successional stages or mature "climax" communities. This paleoecological analysis of a 1.46-m sediment core from swamps on the Caribbean coast of Nicaragua establishes the abundant presence of R, taedigera swamps for ae least 2800 +/- 90 years. R. taedigera swamps must be considered persistent communities, warranting further study because of their great extension into Central and South America. C1 Univ Michigan, Dept Biol, Ann Arbor, MI 48109 USA. RP Urquhart, GR (reprint author), Smithsonian Trop Res Inst, Ctr Paleoecol, Unit 0948, APO, AA 34002 USA. NR 13 TC 9 Z9 9 U1 1 U2 4 PU ASSOC TROPICAL BIOLOGY INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044 USA SN 0006-3606 J9 BIOTROPICA JI Biotropica PD DEC PY 1999 VL 31 IS 4 BP 565 EP 569 DI 10.1111/j.1744-7429.1999.tb00403.x PG 5 WC Ecology SC Environmental Sciences & Ecology GA 274QM UT WOS:000084776600004 ER PT J AU Tobin, MF Lopez, OR Kursar, TA AF Tobin, MF Lopez, OR Kursar, TA TI Responses of tropical understory plants to a severe drought: Tolerance and avoidance of water stress SO BIOTROPICA LA English DT Article DE drought; leaf life span; leaf water potential; Panama; pressure-volume curves; tropical moist forest; water relations ID PRESSURE-VOLUME RELATIONSHIPS; LEAF LIFE-SPAN; NEOTROPICAL FOREST; SEASONAL DROUGHT; MOIST FOREST; SHRUBS; GROWTH; PATTERNS; LEAVES; TREE AB Shade-tolerant understory shrubs and subcanopy trees constitute most of the woody species in Neotropical moist forest, bur studies demonstrating physiological differences among these species are few. Shade-tolerant species that coexist in the forest understory exhibit differences in leaf life span that have been associated with variation in physiological traits. We hypothesized that water relations of understory species with widely divergent leaf life spans differ in response to drought. Although severe drought is infrequent in Neotropical moist Forest, we studied the water relations of shade-tolerant understory species with short or long leaf life spans during the severe 1981-1992 dry season on Barro Colorado Island, Panama. The predawn leaf water potential declined to -2.8 and -3.6 MPa during the dry season in Hybanthus prunifolius and Psychotria horizontalis, respectively two species with shore leaf life spans, but remained above -1.3 MPa in two species with long leaf life spans, Swartzia simplex and Ouratea lucens. The midday leaf water potential dropped as low as -3.4 and -4.5 MPa for H. prunifolius and P. horizontalis, respectively. The osmotic potential of H. prunifolius and P. horizontalis and another species with short leaf life span, Alseis blackiana, decreased early in the dry season, a period during which all three had substantially negative predawn water potential. In contrast, the osmotic potential of S. Simplex, O. Lucens, and Licania platypus, a third species with long leaf life span, declined late in the dry season, even though we observed little change in predawn water potential for S, simplex and O. lucens. We conclude that the variable and potentially severe dry season in Neotropical moist forest can be sufficiently intense to severely limit soil moisture availability for understory planes. H. prunifolius and P horizontalis tolerated dehydration, whereas S. simplex and O. lucens postponed dehydration. C1 Smithsonian Trop Res Inst, Balboa, Panama. Univ Utah, Dept Biol, Salt Lake City, UT 84112 USA. RP Tobin, MF (reprint author), Univ Minnesota, Dept Forest Resources, St Paul, MN 55108 USA. NR 44 TC 25 Z9 29 U1 1 U2 9 PU ASSOC TROPICAL BIOLOGY INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044 USA SN 0006-3606 J9 BIOTROPICA JI Biotropica PD DEC PY 1999 VL 31 IS 4 BP 570 EP 578 DI 10.1111/j.1744-7429.1999.tb00404.x PG 9 WC Ecology SC Environmental Sciences & Ecology GA 274QM UT WOS:000084776600005 ER PT J AU Feller, IC McKee, KL AF Feller, IC McKee, KL TI Small gap creation in Belizean mangrove forests by a wood-boring insect SO BIOTROPICA LA English DT Article DE Avicennia germinans; Belize; cerambycid; Elaphidion mimeticum; indirect herbivory; light gaps; mangrove; Rhizophora mangle; seedling survival; wood-boring insects; xylovory ID TROPICAL FOREST; PHASE REGENERATION; RHIZOPHORA MANGLE; GROWTH; DISTURBANCE; HERBIVORY; DYNAMICS; ECOSYSTEMS; TREES AB We investigated the role of wood-boring insects in the creation of light gaps within mangrove forests. We compared the frequency of gaps caused by wood borers to other gap-forming processes and characterized the physical attributes of light gaps in mangrove forests on small islands in Belize. Methods of quantifying light gaps included aerial photography, ground surveys, and experimental plots. Small light gaps (less than or equal to 12 m(2)) were very common in Rhizophora mangle fringe, comprising almost: 22 percent of these forests. Rhizophora mangle gaps were smaller than gaps in Avicennia germinans forests. In R, mangle forests, gaps were caused by branch death, and in R germinans forests, gaps were caused primarily by downed trees. More than 91 percent of the gap-forming branches and boles in the R. mangle fringe were killed by a wood-boring cerambycid beetle, Elaphidion mimeticum, indicating that it is the major cause of small-scale disturbances in these forests. No trees or branches in the A. germinans forest were attacked by this beetle. In R. mangle forests, small gaps had significantly higher light levels and soil temperatures than areas under the closed canopy; however, soil conditions for sulfide concentrations, porewater salinity and redox potentials were similar in small gaps and under the closed canopy. Survival of R. mangle, A. germinans, and Laguncularia racemosa seedlings was also higher inside these small gaps, indicating their importance in regeneration of mangrove forests. Feeding by wood borers is thus an important type of indirect herbivory in mangrove forests, with a critical role in ecological processes such as gap dynamics. C1 Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. Louisiana State Univ, Wetland Biogeochem Inst, Baton Rouge, LA 70803 USA. RP Feller, IC (reprint author), Smithsonian Environm Res Ctr, POB 28, Edgewater, MD 21037 USA. RI McKee, Karen/D-1365-2014; OI McKee, Karen/0000-0001-7042-670X; Feller, Ilka/0000-0002-6391-1608 NR 49 TC 37 Z9 40 U1 4 U2 16 PU ASSOC TROPICAL BIOLOGY INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044 USA SN 0006-3606 J9 BIOTROPICA JI Biotropica PD DEC PY 1999 VL 31 IS 4 BP 607 EP 617 DI 10.1111/j.1744-7429.1999.tb00408.x PG 11 WC Ecology SC Environmental Sciences & Ecology GA 274QM UT WOS:000084776600009 ER PT J AU Seeger, A AF Seeger, A TI Ruth Crawford Seeger: A composer's search for American music SO ETHNOMUSICOLOGY LA English DT Book Review C1 Smithsonian Folkways Recordings, Washington, DC USA. RP Seeger, A (reprint author), Smithsonian Folkways Recordings, Washington, DC USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU SOC ETHNOMUSICOLOGY INC PI BLOOMINGTON PA MORRISON HALL, ROOM 005 INDIANA UNIVERSITY, BLOOMINGTON, IN 47405 USA SN 0014-1836 J9 ETHNOMUSICOLOGY JI Ethnomusicology PD WIN PY 1999 VL 43 IS 1 BP 171 EP 174 DI 10.2307/852702 PG 4 WC Music SC Music GA 166UA UT WOS:000078594500011 ER PT J AU McCoy, TJ AF McCoy, TJ TI The story of a meteorite SO GEOTIMES LA English DT Article C1 Smithsonian Inst, Natl Museum Nat Hist, Natl Meteorite Collect, Washington, DC 20560 USA. RP McCoy, TJ (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Natl Meteorite Collect, Washington, DC 20560 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER GEOLOGICAL INST PI ALEXANDRIA PA 4220 KING ST, ALEXANDRIA, VA 22302-1507 USA SN 0016-8556 J9 GEOTIMES JI Geotimes PD DEC PY 1999 VL 44 IS 12 BP 19 EP 21 PG 3 WC Geosciences, Multidisciplinary SC Geology GA 262AT UT WOS:000084044100017 ER PT J AU Moran, JM Greenhill, LJ Herrnstein, JR AF Moran, JM Greenhill, LJ Herrnstein, JR TI Observational evidence for massive black holes in the centers of active galaxies SO JOURNAL OF ASTROPHYSICS AND ASTRONOMY LA English DT Article; Proceedings Paper CT Meeting on the Physics of Black Holes CY DEC 08-10, 1997 CL BANGALORE, INDIA SP Indian Inst Sci DE masers; black holes; accretion disks; very long baselines interferometry ID H2O MASER EMISSION; GALACTIC NUCLEI; ACCRETION DISKS; WATER MASERS; NGC-4258; NGC-1068; NGC4258; SEARCH AB Naturally occurring water vapor maser emission at 1.35 cm wavelength provides an accurate probe for the study of accretion disks around highly compact objects, thought to be black holes, in the centers of active galaxies. Because of the exceptionally fine angular resolution, 200 microarcseconds, obtainable with very long baseline interferometry, accompanied by high spectral resolution, < 0.1 km s(-1), the dynamics and structures of these disks can be probed with exceptional clarity. The data on the galaxy NGC 4258 are discussed here in detail. The mass of the black hole binding the accretion disk is 3.9 x 10(7) M.. Although the accretion disk has a rotational period of about 800 years, the physical motions of the masers have been directly measured with VLBI over a period of a few years. These measurements also allow the distance from the earth to the black hole to be estimated to an accuracy of 4 per cent. The status of the search for other maser/black hole candidates is also discussed. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 67 TC 35 Z9 35 U1 0 U2 0 PU INDIAN ACAD SCIENCES PI BANGALORE PA C V RAMAN AVENUE, SADASHIVANAGAR, P B #8005, BANGALORE 560 080, INDIA SN 0250-6335 EI 0973-7758 J9 J ASTROPHYS ASTRON JI J. Astrophys. Astron. PD DEC PY 1999 VL 20 IS 3-4 BP 165 EP 185 DI 10.1007/BF02702350 PG 21 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 281ME UT WOS:000085163700007 ER PT J AU Kolman, CJ Centurion-Lara, A Lukehart, SA Owsley, DW Tuross, N AF Kolman, CJ Centurion-Lara, A Lukehart, SA Owsley, DW Tuross, N TI Identification of Treponema pallidum subspecies pallidum in a 200-year-old skeletal specimen SO JOURNAL OF INFECTIOUS DISEASES LA English DT Article ID SYPHILIS; DIAGNOSIS; DNA AB Treponema pallidum subsp, pallidum, the causative agent of venereal syphilis, was detected in a 200-year-old skeletal specimen from Easter Island. An initial diagnosis of treponemal infection was confirmed by extensive purification of immunoglobulin that reacted strongly with T. pallidum antigen, Extracted DNA exhibited a single-base polymorphism that distinguished T.p. subsp, pallidum from 4 other human and nonhuman treponemes, Extensive precautions against contamination of the subject matter with modern treponemal DNA were employed, including analysis of archaeological and modern specimens in 2 geographically separate laboratories. Molecular determination of historical disease scares by using skeletal material can significantly enhance our understanding of the pathology and spread of infectious diseases. C1 Smithsonian Ctr Mat Res & Educ, Suitland, MD 20746 USA. Univ Washington, Dept Med, Seattle, WA USA. Smithsonian Inst, Dept Anthropol, Washington, DC 20560 USA. RP Tuross, N (reprint author), Smithsonian Ctr Mat Res & Educ, 4210 Silver Hill Rd, Suitland, MD 20746 USA. NR 14 TC 55 Z9 56 U1 1 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0022-1899 J9 J INFECT DIS JI J. Infect. Dis. PD DEC PY 1999 VL 180 IS 6 BP 2060 EP 2063 DI 10.1086/315151 PG 4 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA 263QW UT WOS:000084137600044 PM 10558971 ER PT J AU Wong, GP Tseng, CH Pomeroy, VR Mair, RW Hinton, DP Hoffmann, D Stoner, RE Hersman, FW Cory, DG Walsworth, RL AF Wong, GP Tseng, CH Pomeroy, VR Mair, RW Hinton, DP Hoffmann, D Stoner, RE Hersman, FW Cory, DG Walsworth, RL TI A system for low field imaging of laser-polarized noble gas SO JOURNAL OF MAGNETIC RESONANCE LA English DT Article DE laser-polarized noble gas; low magnetic field; magnetic resonance imaging; lung imaging; radiation damping ID HYPERPOLARIZED HE-3; RESONANCE; DIFFUSION; XE-129; MRI AB We describe a device for performing MRI: with laser-polarized noble gas at low magnetic fields (<50 G). The system is robust, portable, inexpensive, and provides gas-phase imaging resolution comparable to that of high field clinical instruments. At 20.6 G, we have imaged laser-polarized He-3 (Larmor frequency of 67 kHz) in both sealed glass cells and excised rat lungs, using similar to 0.1 G/cm gradients to achieve similar to 1 mm(2) resolution. In addition, we measured He-3 T-2(*) times greater than 100 ms in excised rat lungs, which is roughly 20 times longer than typical values observed at high (similar to 2 T) fields. We include a discussion of the practical considerations for working at low magnetic fields and conclude with evidence of radiation damping in this system. (C) 1999 academic Press. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. MIT, Dept Nucl Engn, Cambridge, MA 02138 USA. Univ New Hampshire, Dept Phys, Durham, NH 03824 USA. Massachusetts Gen Hosp, NMR Ctr, Charlestown, MA 02129 USA. RP Wong, GP (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. OI Stoner, Richard/0000-0001-7949-6747 NR 25 TC 40 Z9 40 U1 0 U2 8 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1090-7807 J9 J MAGN RESON JI J. Magn. Reson. PD DEC PY 1999 VL 141 IS 2 BP 217 EP 227 DI 10.1006/jmre.1999.1904 PG 11 WC Biochemical Research Methods; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Biochemistry & Molecular Biology; Physics; Spectroscopy GA 263RZ UT WOS:000084140200003 PM 10579945 ER PT J AU Center, BJ Giblin-Davis, RM Herre, EA Chung-Schickler, GC AF Center, BJ Giblin-Davis, RM Herre, EA Chung-Schickler, GC TI Histological comparisons of parasitism by Schistonchus spp. (Nemata : Aphelenchoididae) in neotropical Ficus spp. SO JOURNAL OF NEMATOLOGY LA English DT Article DE Aphelenchoididae; Ficus aurea; Ficus glabrata; Ficus laevigata; Ficus maxima; Ficus poponoei; Ficus trigonata; fig; floret wall morphology; histopathology; life history; nematode; parasitism; Schistonchus spp. ID BLASTOPHAGA-PSENES; AGAONIDAE; SYCONIA; FIGS AB Syconia (enclosed infructescences) infested with host-specific species of Schistonchus (Aphelenchoididae) were collected from six species of Ficus (Moraceae) native to Florida or Panama. They were sectioned and histologically examined to assess the effects of parasitism. Parasitism by Schistonchus spp. was associated with hypertrophied cells, tissue necrosis, and the presence of an exudate in all species. Occasional hypertrophy of the outer epidermal cells occurred on seed florets, wasp florets, and on the endothecial cells of male florets in F. aurea (subgenus Urostigma) from Florida. Aberrations of the inner mesocarp occurred under the hypertrophied cells on seed florets. In F. laevigata (subgenus Urostigma) from Florida, Schistonchus sp. infested immature male florets and was associated with hypertrophy of endothecial cells, epidermal cells of the anther filaments, and anthers. Schistonchus sp. also caused aberrations of the anther filament, anthers, and pollen. Ficus poponoei (subgenus Urostigma) and F. glabrata (subgenus Pharmacosycea), both from Panama, had hypertrophied outer epidermal cells on seed florets. Ficus poponoei also had Schistonchus sp. within the pedicel of an aborted floret, with hypertrophy of the cortical parenchyma. Ficus trigonata (subgenus Urostigma) from Panama had hypertrophy of the outer epidermis of seed florets. When the outer epidermis on these florets was missing, the inner mesocarp was hypertrophied. Ficus maxima (subgenus Pharmacosycea) from Panama had hypertrophy on the outer epidermis of seed and aborted florets. Schistonchus spp. were not found in wasp larvae or pupae in any of the Ficus spp. examined. Hypertrophy was never observed in the absence of Schistonchus spp. C1 Univ Florida, Inst Food & Agr Sci, Ft Lauderdale Res & Educ Ctr, Ft Lauderdale, FL 33314 USA. Smithsonian Trop Res Inst, Unit 0948, APO, AA 34002 USA. RP Center, BJ (reprint author), Univ Florida, Inst Food & Agr Sci, Ft Lauderdale Res & Educ Ctr, 3205 Coll Ave, Ft Lauderdale, FL 33314 USA. NR 14 TC 15 Z9 16 U1 0 U2 4 PU SOC NEMATOLOGISTS PI LAKELAND PA 3012 SKYVIEW DRIVE, LAKELAND, FL 33801-7072 USA SN 0022-300X J9 J NEMATOL JI J. Nematol. PD DEC PY 1999 VL 31 IS 4 BP 393 EP 406 PG 14 WC Zoology SC Zoology GA 283CT UT WOS:000085259100005 PM 19270912 ER PT J AU Kito, K Hope, WD AF Kito, K Hope, WD TI Leptosomatides brevicaudatus n. sp and a redescription of Leptosomatides marinae Platonova, 1967 (Enoplida : Leptosomatidae) SO JOURNAL OF NEMATOLOGY LA English DT Article DE Leptosomatides brevicaudatus; Leptosomatides marinae; marine nematode; nematode; new species; SEM observation; subventral supplement; taxonomy AB The free-living marine nematodes Leptosomatides brevicaudatus n. sp. and L. marinae were described and redescribed, respectively, from material collected in the northwest Pacific. Leptosomatides brevicaudatus n. sp. from Simushir Island differs from L. marinae in the ratio c' (body length divided by tail length measured on the chord) and the length of the spicules. Leptosomatides marinae is redescribed from light microscopy (LM) observations of the type specimens and LM and scanning electron microscopy (SEM) observations of specimens from Hokkaido, Japan. It appears to be impossible to distinguish among some species of Leptosomatides because they are either insufficiently described or known only from females. Secondary sexual characters of males are essential for purposes of identification. C1 Sapporo Med Univ, Sch Med, Dept Biol, Sapporo, Hokkaido 0608556, Japan. Smithsonian Inst, Natl Museum Nat Hist, Dept Invertebrate Zool, Washington, DC 20560 USA. RP Kito, K (reprint author), Sapporo Med Univ, Sch Med, Dept Biol, Sapporo, Hokkaido 0608556, Japan. NR 17 TC 0 Z9 1 U1 0 U2 0 PU SOC NEMATOLOGISTS PI LAKELAND PA 3012 SKYVIEW DRIVE, LAKELAND, FL 33801-7072 USA SN 0022-300X J9 J NEMATOL JI J. Nematol. PD DEC PY 1999 VL 31 IS 4 BP 460 EP 474 PG 15 WC Zoology SC Zoology GA 283CT UT WOS:000085259100012 PM 19270919 ER PT J AU Chinain, M Faust, MA Pauillac, S AF Chinain, M Faust, MA Pauillac, S TI Morphology and molecular analyses of three toxic species of Gambierdiscus (Dinophyceae): G-pacificus, sp nov., G-australes, sp nov., and G-polynesiensis, sp nov. SO JOURNAL OF PHYCOLOGY LA English DT Article DE Belize; benthic; ciguatoxins; dinoflagellates; Dinophyceae; French Polynesia; Gambierdiscus australes sp nov.; Gambierdiscus pacificus sp nov.; Gambierdiscus polynesiensis sp nov.; isozyme electrophoresis; large subunit rDNA; morphology; SEM; taxonomy ID DISTRIBUTED ALEXANDRIUM DINOPHYCEAE; NORTHEASTERN UNITED-STATES; RIBOSOMAL-RNA GENES; INTRASPECIFIC VARIATION; NATURAL-POPULATIONS; GENUS ALEXANDRIUM; ISOZYME ANALYSIS; INCLUDING 2; CORAL-REEF; DINOFLAGELLATE AB Three new dinoflagellate species, Gambierdiscus polynesiensis, sp. nov., Gambierdiscus australes, sp. nov., and Gambierdiscus pacificus, sp. nov., are described from scanning electron micrographs. The morphology of the three new Ganbierdisclls species is compared with the type species Gambierdiscus toxicus Adachi et Fukuyo 1979, and two other species: Gambierdiscus belizeanus Faust 1995 and Gambierdiscus yasumotoi Holmes 1998. The plate formula is: Po, 3', 7 ", 6C, 8S, 5''', 1p, 2''''. Culture extracts of these three new species displayed both ciguatoxin- and maitotoxin-like toxicities. The following morphological characteristics differentiated each species. 1) Cells of G. polynesiensis are 68-85 mu m long and 64-75 mu m wide, and the cell's surface is smooth. They are identified by a large triangular apical pore plate (Po), a narrow fish-hook opening surrounded by 38 round pores, and a large, broad posterior intercalary plate (1p) wedged between narrow postcingular plates 2'''' and 4'''. Plate 1p occupies 60% of the width of the hypotheca. 2) Cells of G. australes also have a smooth surface and are 76-93 mu m long and 65-85 mu m wide in dorsoventral depth. They are identified by the broad ellipsoid apical pore plate (Po) surrounded by 31 round pores and a long and narrow Ip plate wedged between postcingular plates 2''' and 4'''. Plate Ip occupies 30% of the width of the hypotheca. 3) Cells of G. pacificus are 67-77 mu m long and 60-76 mu m wide in dorsoventral depth, and its surface is smooth. They are identified by the four-sided apical pore plate (Po) surrounded by 30 round pores. A short narrow 1p plate is wedged between the wide postcingular plates 2''' and 4'''. Plate 1p occupies 20% of the width of the hypotheca. These three newly described species were also characterized by isozyme electrophoresis and DNA sequencing of the D8-D10 region of their large subunit (LSU) rRNA genes. The consistency between species designations based on SEM micros-copy and classification inferred from biochemical and genetic heterogeneities was examined among seven isolates of Gambierdiscus. Their classification into four morphospecies was not consistent with groupings inferred from isozyme patterns. Three molecular types could be distinguished based on the comparison of their LSU rDNA sequences. Although G. toxicus TUR was found to be more closely related to G. pacificus, sp. nov, than to other G. toxicus strains, the molecular classification was able to discriminate G. polynesiensis, sp. nov, and G. australes, sp. nov. from G. foxicus. These results suggest the usefulness of the D8-D10 portion of the Gambierdiscus LSU rDNA as a valuable taxonomic marker. C1 Inst Terr Rech Med Louis Malarde, Tahiti, Fr Polynesia. Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, Suitland, MD 20746 USA. RP Chinain, M (reprint author), Inst Terr Rech Med Louis Malarde, BP 30 Papeete, Tahiti, Fr Polynesia. EM mchinain@malarde.pf NR 73 TC 81 Z9 93 U1 5 U2 14 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0022-3646 J9 J PHYCOL JI J. Phycol. PD DEC PY 1999 VL 35 IS 6 BP 1282 EP 1296 DI 10.1046/j.1529-8817.1999.3561282.x PG 15 WC Plant Sciences; Marine & Freshwater Biology SC Plant Sciences; Marine & Freshwater Biology GA 274JF UT WOS:000084762200022 ER PT J AU Polhemus, DA Polhemus, JT AF Polhemus, DA Polhemus, JT TI Naucoridae (Heteroptera) of new guinea. 6. A revision of the genera Sagocoris and Aptinocoris, with descriptions of new species SO JOURNAL OF THE NEW YORK ENTOMOLOGICAL SOCIETY LA English DT Article AB The taxonomy of the creeping water bugs belonging to the genera Sagocoris and Aptinocoris, which are end(:mic to New Guinea and nearby islands, is revised. The following new species are described: Sagocaris intermedius from central Irian Jaya, Sagocoris irianus from northern Irian Jaya, :Sagocoris flavinotum from northern Irian Jaya, Aptinocoris sogeri from southeastern Papua New Guinea, Aptinocoris minutus from northern Papua New Guinea, Aptinocoris boikiki from northeastern Papua New Guinea, and Aptinocoris ziwa from northern Irian Jaya. The following new generic assignments are proposed (new combinations given second): Sagocoris fenneri = Aptinocoris fenneri; Sagocoris sedlaceki = Aptinocoris sedlaceki; Sagocoris cheesmanae = Aptinocaris cheesmanae; Quadricoris asymmetrica = Sagocoris asymmetricus. The following new synonyms are proposed (junior synonyms listed first): Quadricoris La Rivers = Sagocoris Montandon; 'Truncocoris La Rivers = Aptinocoris Montandon; Sagocoris browni La Rivers = Aptinocoris papuus Montandon. The supergenera Margodes and Margallus proposed by La Rivers are considered invalid names since they refer to a taxonomic category that has no official status under the present Code. Illustrations are provided for the male genital structures and female pregenital structures for all Sagocoris and Aptinocoris species, along with maps detailing the distributions of these species within New Guinea. C1 Smithsonian Inst, Dept Entomol, Washington, DC 20560 USA. RP Polhemus, DA (reprint author), Smithsonian Inst, Dept Entomol, MRC 105, Washington, DC 20560 USA. NR 5 TC 1 Z9 1 U1 1 U2 1 PU NEW YORK ENTOMOLOGICAL SOC INC PI NEW YORK PA C/O AMER MUSEUM NAT HIST 79TH & CENTRAL PARK WEST, NEW YORK, NY 10024 USA SN 0028-7199 J9 J NEW YORK ENTOMOL S JI J. N.Y. Entomol. Soc. PD WIN PY 1999 VL 107 IS 4 BP 331 EP 371 PG 41 WC Entomology SC Entomology GA 332AB UT WOS:000088049900004 ER PT J AU Terio, KA Citino, SB Brown, JL AF Terio, KA Citino, SB Brown, JL TI Fecal cortisol metabolite analysis for noninvasive monitoring of adrenocortical function in the cheetah (Acinonyx jubatus) SO JOURNAL OF ZOO AND WILDLIFE MEDICINE LA English DT Article DE cheetah; feces; cortisol metabolites; adrenal gland; ACTH ID NORTH-AMERICAN ZOOS; CAT FELIS-CATUS; RHESUS-MONKEYS; DOMESTIC CAT; STRESS; ANIMALS; ESTRADIOL; DISTRESS; FECES AB A radioimmunoassay was validated fur quantifying excreted cortisol metabolites in cheetah (Acinonyx jubatus) feces. High-performance liquid chromatography analysis indicated that immunoreactivity was associated with a water-soluble metabolite in fecal extracts from males and females. None of the immunoreactivity corresponded with free cortisol or corticosterone but rather was associated with a more polar, unidentified metabolite. To determine the biologic relevance of excreted immunoreactive cortisol metabolites, cheetahs were exposed to a variety of situations anticipated to increase cortisol secretion. First. to assess acute changes in adrenal activity. adrenocorticotropic hormone (ACTH; 400 IU i.m.) was administered to two adult males and two adult females. Pre-ACTH baseline serum cortisol and fecal cortisol metabolite concentrations varied among individuals. Serum cortisol concentrations were elevated above baseline within 10 min of ACTH injection. followed by corresponding increases in fecal cortisol metabolite concentrations (690-4,194% above baseline) 38 hr Inter in three of four cheetahs. In the fourth cheetah. a smaller increase (334% above baseline) in fecal cortisol metabolite excretion was observed 90 hr after ACTH injection. Seven cheetah females also were subjected to a variety of potentially stressful manipulations. including immobilization, translocation. and introduction to a male to assess the ability of this technique to detect physiologic changes in adrenal activity. Increased fecal corticoid metabolite excretion was observed 21-72 hr after exposure to these exogenous stressors. Results indicate that adrenocortical activity can be monitored noninvasively in the cheetah through analysis of these metabolites. This technique could be valuable for evaluating, and thus optimizing, environmental and management conditions and for investigating the role of stress: in disease pathogenesis and the usually poor reproductive performance of this species in captivity. C1 White Oak Conservat Ctr, Yulee, FL 32097 USA. Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA 22630 USA. RP Terio, KA (reprint author), Univ Calif Davis, Sch Vet Med, Dept Pathol Microbiol & Immunol, Davis, CA 95616 USA. NR 31 TC 51 Z9 55 U1 1 U2 16 PU AMER ASSOC ZOO VETERINARIANS PI MEDIA PA 6 NORTH PENNELL ROAD, MEDIA, PA 19063 USA SN 1042-7260 J9 J ZOO WILDLIFE MED JI J. Zoo Wildl. Med. PD DEC PY 1999 VL 30 IS 4 BP 484 EP 491 PG 8 WC Veterinary Sciences SC Veterinary Sciences GA 292BK UT WOS:000085774100002 PM 10749432 ER PT J AU Kalfatovic, MR AF Kalfatovic, MR TI Compass and clock: Defining moments in American culture: 1800, 1850, 1900. SO LIBRARY JOURNAL LA English DT Book Review C1 Smithsonian Inst Libs, Washington, DC 20560 USA. RP Kalfatovic, MR (reprint author), Smithsonian Inst Libs, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU BOWKER MAGAZINE GROUP CAHNERS MAGAZINE DIVISION PI NEW YORK PA 249 W 17TH ST, NEW YORK, NY 10011 USA SN 0363-0277 J9 LIBR J JI Libr. J. PD DEC PY 1999 VL 124 IS 20 BP 128 EP 128 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 271AK UT WOS:000084569100074 ER PT J AU Riley, SM AF Riley, SM TI Tea. SO LIBRARY JOURNAL LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Riley, SM (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU BOWKER MAGAZINE GROUP CAHNERS MAGAZINE DIVISION PI NEW YORK PA 249 W 17TH ST, NEW YORK, NY 10011 USA SN 0363-0277 J9 LIBR J JI Libr. J. PD DEC PY 1999 VL 124 IS 20 BP 184 EP 184 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 271AK UT WOS:000084569100319 ER PT J AU Kurin, R AF Kurin, R TI The vanguard of the Islamic revolution: The Jama'at-i Islami of Pakistan SO MIDDLE EAST JOURNAL LA English DT Book Review C1 Smithsonian Inst, Ctr Folklife Programs & Cultural Studies, Washington, DC 20560 USA. RP Kurin, R (reprint author), Smithsonian Inst, Ctr Folklife Programs & Cultural Studies, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU MIDDLE EAST INSTITUTE PI WASHINGTON PA 1761 N STREET NW, CIRCULATION DEPT, WASHINGTON, DC 20036-2882 USA SN 0026-3141 J9 MIDDLE EAST J JI Middle East J. PD WIN PY 1999 VL 53 IS 1 BP 128 EP 129 PG 2 WC Area Studies SC Area Studies GA 162EB UT WOS:000078331600012 ER PT J AU Johnson, WE Slattery, JP Eizirik, E Kim, JH Raymond, MM Bonacic, C Cambre, R Crawshaw, P Nunes, A Seuanez, HN Moreira, MAM Seymour, KL Simon, F Swanson, W O'Brien, SJ AF Johnson, WE Slattery, JP Eizirik, E Kim, JH Raymond, MM Bonacic, C Cambre, R Crawshaw, P Nunes, A Seuanez, HN Moreira, MAM Seymour, KL Simon, F Swanson, W O'Brien, SJ TI Disparate phylogeographic patterns of molecular genetic variation in four closely related South American small cat species SO MOLECULAR ECOLOGY LA English DT Article DE conservation genetics; evolution; microsatellites; mitochondrial DNA; phylogeography; South American felids ID MITOCHONDRIAL-DNA; PHYLOGENETIC RECONSTRUCTION; RIBOSOMAL-RNA; DOMESTIC CAT; FELIDAE; SEQUENCES; MICROSATELLITES; CHROMOSOME; EVOLUTION; RODENTS AB Tissue specimens from four species of Neotropical small cats (Oncifelis geoffroyi, N = 38; O. guigna, N = 6; Leopardus tigrinus, N = 32; Lynchailurus colocolo, N = 22) collected from throughout their distribution were examined for patterns of DNA sequence variation using three mitochondrial genes, 16S rRNA, ATP8, and NADH-5. Patterns between and among O. guigna and O. geoffroyi individuals were assessed further from size variation at 20 microsatellite loci. Phylogenetic analyses using mitochondrial DNA sequences revealed monophyletic clustering of the four species, plus evidence of natural hybridization between L. tigrinus and L. colocolo in areas of range overlap and discrete population subdivisions reflecting geographical isolation. Several commonly accepted subspecies partitions were affirmed for L. colocolo, but not for O. geoffroyi. The lack of geographical substructure in O. geoffroyi was recapitulated with the microsatellite data, as was the monophyletic clustering of O. guigna and O. geoffroyi individuals. L. tigrinus forms two phylogeographic clusters which correspond to L.t. oncilla (from Costa Rica) and L.t. guttula (from Brazil) and which have mitochondrial DNA (mtDNA) genetic distance estimates comparable to interspecific values between other ocelot lineage species. Using feline-specific calibration rates for mitochondrial DNA mutation rates, we estimated that extant lineages of O. guigna diverged 0.4 million years ago (Ma), compared with 1.7 Ma for L. colocolo, 2.0 Ma for O. geoffroyi, and 3.7 Ma for L. tigrinus. C1 NCI, Lab Genom Divers, Ft Detrick, MD 21702 USA. Univ Catolica, Dept Ingn Forestal, Santiago, Chile. Smithsonian Inst, Natl Zool Pk, Dept Anim Hlth, Washington, DC 20008 USA. CENAP, IBAMA, Sorocaba, Brazil. Zoo Municipal Sorocaba, Sorocaba, Brazil. Inst Nacl Canc, Serv Pesquisa Basica, Rio De Janeiro, Brazil. Royal Ontario Museum, Dept Palaeobiol, Toronto, ON M5S 2C6, Canada. Parque Zool Sao Paulo, Sao Paulo, Brazil. Cincinnati Zoo & Bot Garden, Cincinnati, OH 45267 USA. RP Johnson, WE (reprint author), NCI, Lab Genom Divers, Ft Detrick, MD 21702 USA. EM johnsonw@ncifcrf.gov RI Eizirik, Eduardo/K-8034-2012; Johnson, Warren/D-4149-2016 OI Eizirik, Eduardo/0000-0002-9658-0999; Johnson, Warren/0000-0002-5954-186X NR 52 TC 28 Z9 34 U1 1 U2 21 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0962-1083 EI 1365-294X J9 MOL ECOL JI Mol. Ecol. PD DEC PY 1999 VL 8 IS 12 SU 1 BP S79 EP S94 DI 10.1046/j.1365-294X.1999.00796.x PG 16 WC Biochemistry & Molecular Biology; Ecology; Evolutionary Biology SC Biochemistry & Molecular Biology; Environmental Sciences & Ecology; Evolutionary Biology GA 291MB UT WOS:000085737800009 PM 10703553 ER PT J AU Terlevich, AI Kuntschner, H Bower, RG Caldwell, N Sharples, RM AF Terlevich, AI Kuntschner, H Bower, RG Caldwell, N Sharples, RM TI Colour-magnitude relations and spectral line strengths in the Coma cluster SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE galaxies : abundances; galaxies : clusters : individual : Coma; galaxies : elliptical and lenticular, cD; galaxies : formation; galaxies : starburst ID EARLY-TYPE GALAXIES; ELLIPTICAL GALAXIES; MORPHOLOGICAL CLASSIFICATION; STRUCTURAL PARAMETERS; VELOCITY DISPERSIONS; NEARBY CLUSTERS; STAR-FORMATION; S0 GALAXIES; EVOLUTION; MODEL AB We use the C(2)4668, Fe4383, H gamma(A) and H delta(A) spectral absorption line indices, together with U- and V-band photometry of 101 galaxies in the Coma cluster, to investigate how mean age and metal abundance correlate with galaxy luminosity. In particular, we use the line index measurements to address the origin of the colour-magnitude relation (CMR). We find that the CMR in Coma is driven primarily by a luminosity-metallicity correlation. We additionally show evidence for a relation between age and luminosity, in the direction predicted by the semi-analytic hierarchical clustering models of Kauffmann & Charlot, but this is only present in the C(2)4668 index models, and could be an effect of the lack of non-solar abundance ratios in the Worthey models used. By comparing deviations from the CMR with deviations in absorption index from analogous 'index-magnitude' relations, we find that colour deviations bluewards of the mean relation are strongly correlated with the hydrogen Balmer line series absorption. We show that the properties of these blue galaxies are consistent with the presence of a young stellar population in the galaxies, rather than with a reduced metallicity. C1 Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Univ Durham, Durham DH1 3LE, England. Smithsonian Inst, FL Whipple Observ, Amado, AZ 85645 USA. RP Terlevich, AI (reprint author), Univ Birmingham, Birmingham B15 2TT, W Midlands, England. EM ale@star.sr.bham.ac.uk RI Sharples, Ray/N-7309-2013 OI Sharples, Ray/0000-0003-3449-8583 NR 51 TC 54 Z9 54 U1 0 U2 0 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. PY 1999 VL 310 IS 2 BP 445 EP 452 DI 10.1046/j.1365-8711.1999.02941.x PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 264PQ UT WOS:000084191000017 ER PT J AU Griesmann, U Burnett, JH AF Griesmann, U Burnett, JH TI Refractivity of nitrogen gas in the vacuum ultraviolet SO OPTICS LETTERS LA English DT Article AB We have measured the refractivity of nitrogen gas in the ultraviolet and the vacuum ultraviolet, using a Fourier-transform spectrometer. A new two-term Sellmeier formula for the standard refractivity between 145 and 270 nm is derived. (C) 1999 Optical Society of America. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02139 USA. RP Griesmann, U (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 9 TC 20 Z9 22 U1 0 U2 3 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 DEC 1 PY 1999 VL 24 IS 23 BP 1699 EP 1701 DI 10.1364/OL.24.001699 PG 3 WC Optics SC Optics GA 260PW UT WOS:000083959900015 PM 18079907 ER PT J AU Eble, GJ AF Eble, GJ TI On the dual nature of chance in evolutionary biology and paleobiology SO PALEOBIOLOGY LA English DT Article ID COORDINATED STASIS; SPECIES SELECTION; RANDOM CLADES; CHAOS; PATTERN; MACROEVOLUTION; SIMULATIONS; CONSTRAINT; EXTINCTION; SPANDRELS AB The identification of randomness and nonrandomness is a perennial problem in evolutionary research. Stochastic thinking in evolutionary biology and paleobiology has solidified the use of a statistical notion of chance, but the idea of chance in evolutionary studies goes beyond statistics. A duality arises from the use of a statistical meaning on the one hand, and a more strictly evolutionary meaning on the other. The former implies a combination of indiscriminate sampling and unpredictability due to multiple causes; the latter codifies independence from adaptation and the directionality imposed by natural selection. Often these meanings are kept separate in evolutionary research, used in isolation according to the empirical situation or the goal of the investigator (recognition of pattern versus process). I argue that evolutionary studies in general and paleobiological studies in particular can benefit from the simultaneous application of statistical and evolutionary notions of chance. Following some background on the notion of chance and its use, I discuss a series of examples in which insight can be gained by explicit consideration of both meanings. Thus, typologies of extinction become clearer when phenomena like wanton extinction are made explicit; exaptive radiations are exposed as an alternative to adaptive radiations; the possible nonadaptive nature of deterministic chaos becomes sensible; the nonrandomness of community-assembly is put into question; parallel taxonomies of sorting rooted in different notions of nonrandomness are suggested as a means of facilitating understanding of relationships across the hierarchy; developmental constraints and self-organization are more easily distinguished from selective constraints; and a new term, "incidentals," is suggested to refer to both exaptations and nonaptations. Finally, I point to ways in which the dichotomy between chance and necessity can be approached in evolutionary theory, by showing that the dual nature of chance in evolution entails a distinction between functional and structural necessity, and that chance ultimately becomes a unifying concept for a number of criticisms to neo-Darwinism. C1 Univ Chicago, Comm Evolutionary Biol, Chicago, IL 60637 USA. RP Eble, GJ (reprint author), Smithsonian Inst, Dept Paleobiol, Washington, DC 20560 USA. EM ebleg@nmnh.si.edu NR 85 TC 17 Z9 18 U1 1 U2 9 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA SN 0094-8373 EI 1938-5331 J9 PALEOBIOLOGY JI Paleobiology PD WIN PY 1999 VL 25 IS 1 BP 75 EP 87 PG 13 WC Biodiversity Conservation; Ecology; Evolutionary Biology; Paleontology SC Biodiversity & Conservation; Environmental Sciences & Ecology; Evolutionary Biology; Paleontology GA 177RJ UT WOS:000079224600005 ER PT J AU Krause, GH Schmude, C Garden, H Koroleva, OY Winter, K AF Krause, GH Schmude, C Garden, H Koroleva, OY Winter, K TI Effects of solar ultraviolet radiation on the potential efficiency of photosystem II in leaves of tropical plants SO PLANT PHYSIOLOGY LA English DT Article ID UV-B RADIATION; XANTHOPHYLL-CYCLE ACTIVITY; RYE SECALE-CEREALE; HIGH-LIGHT STRESS; D1 PROTEIN; PHENYLPROPANOID COMPOUNDS; CHLOROPHYLL FLUORESCENCE; CO2 ASSIMILATION; EXCESS LIGHT; PHOTOINHIBITION AB The effects of solar ultraviolet (UV)-B and UV-A radiation on the potential efficiency of photosystem II (PSII) in leaves of tropical plants were investigated in Panama (9 degrees N). Shade-grown tree seedlings or detached sun leaves from the outer crown of mature trees were exposed for short periods (up to 75 min) to direct sunlight filtered through plastic or glass filters that absorbed either UV-B or UV-A+B radiation, or transmitted the complete solar spectrum. Persistent changes in potential PSII efficiency were monitored by means of the dark-adapted ratio of variable to maximum chlorophyll a fluorescence. In leaves of shade-grown tree seedlings, exposure to the complete solar spectrum resulted in a strong decrease in potential PSII efficiency, probably involving protein damage. A substantially smaller decline in the dark-adapted ratio of variable to maximum chlorophyll a fluorescence was observed when UV-B irradiation was excluded. The loss in PSII efficiency was further reduced by excluding both UV-B and UV-A light. The photoinactivation of PSII was reversible under shade conditions, but restoration of nearly full activity required at least 10 d. Repeated exposure to direct sunlight induced an increase in the pool size of xanthophyll cycle pigments and in the content of UV-absorbing vacuolar compounds. In sun leaves of mature trees, which contained high levels of UV-absorbing compounds, effects of UV-B on PSII efficiency were observed in several cases and varied with developmental age and acclimation state of the leaves. The results show that natural UV-B and UV-A radiation in the tropics may significantly contribute to photoinhibition of PSII during sun exposure in situ, particularly in shade leaves exposed to full sunlight. C1 Univ Dusseldorf, Inst Plant Biochem, D-40225 Dusseldorf, Germany. Smithsonian Trop Res Inst, Balboa, Panama. Russian Acad Sci, VL Komarov Bot Inst, St Petersburg 197376, Russia. RP Krause, GH (reprint author), Univ Dusseldorf, Inst Plant Biochem, Univ Str 1,Gebaude 26-03, D-40225 Dusseldorf, Germany. NR 43 TC 47 Z9 54 U1 1 U2 6 PU AMER SOC PLANT PHYSIOLOGISTS PI ROCKVILLE PA 15501 MONONA DRIVE, ROCKVILLE, MD 20855 USA SN 0032-0889 J9 PLANT PHYSIOL JI Plant Physiol. PD DEC PY 1999 VL 121 IS 4 BP 1349 EP 1358 DI 10.1104/pp.121.4.1349 PG 10 WC Plant Sciences SC Plant Sciences GA 266CA UT WOS:000084282000029 ER PT J AU Lubar, S AF Lubar, S TI American material culture: The shape of the field SO PUBLIC HISTORIAN LA English DT Book Review C1 Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. RP Lubar, S (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU UNIV CALIF PRESS PI BERKELEY PA JOURNALS DEPT 2120 BERKELEY WAY, BERKELEY, CA 94720 USA SN 0272-3433 J9 PUBL HISTORIAN JI Public Hist. PD WIN PY 1999 VL 21 IS 1 BP 112 EP 115 PG 4 WC History SC History GA 184TE UT WOS:000079628900021 ER PT J AU Johnson, PJ AF Johnson, PJ TI Lighthouses and keepers: The US Lighthouse Service and its legacy SO PUBLIC HISTORIAN LA English DT Book Review C1 Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. RP Johnson, PJ (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU UNIV CALIF PRESS PI BERKELEY PA JOURNALS DEPT 2120 BERKELEY WAY, BERKELEY, CA 94720 USA SN 0272-3433 J9 PUBL HISTORIAN JI Public Hist. PD WIN PY 1999 VL 21 IS 1 BP 136 EP 138 PG 3 WC History SC History GA 184TE UT WOS:000079628900032 ER PT J AU Rothenberg, M AF Rothenberg, M TI Beyond the ionosphere: Fifty years of satellite communication SO PUBLIC HISTORIAN LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Rothenberg, M (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU UNIV CALIF PRESS PI BERKELEY PA JOURNALS DEPT 2120 BERKELEY WAY, BERKELEY, CA 94720 USA SN 0272-3433 J9 PUBL HISTORIAN JI Public Hist. PD WIN PY 1999 VL 21 IS 1 BP 138 EP 140 PG 3 WC History SC History GA 184TE UT WOS:000079628900033 ER PT J AU Monnier, JD AF Monnier, JD TI Infrared interferometry and spectroscopy of circumstellar envelopes SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. RP Monnier, JD (reprint author), Smithsonian Astrophys Observ, MS 42,60 Garden St, Cambridge, MA 02138 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 DEC PY 1999 VL 111 IS 766 BP 1586 EP 1586 DI 10.1086/316472 PG 1 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 262XC UT WOS:000084092700010 ER PT J AU Perez, M Lassalle, Y AF Perez, M Lassalle, Y TI Interview with Pepon Osorio (Contemporary Latino art in the US, Puerto Rican communities) SO RADICAL HISTORY REVIEW LA English DT Article C1 Smithsonian Inst, Washington, DC 20560 USA. Knox Coll, Galesburg, IL USA. RP Perez, M (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0163-6545 J9 RADICAL HIST REV JI Radic. Hist. Rev. PD WIN PY 1999 IS 73 BP 4 EP 21 PG 18 WC History SC History GA 156MQ UT WOS:000078005500002 ER PT J AU Lefsky, MA Cohen, WB Acker, SA Parker, GG Spies, TA Harding, D AF Lefsky, MA Cohen, WB Acker, SA Parker, GG Spies, TA Harding, D TI Lidar remote sensing of the canopy structure and biophysical properties of Douglas-fir western hemlock forests SO REMOTE SENSING OF ENVIRONMENT LA English DT Article ID LEAF-AREA INDEX; NORTHERN HARDWOOD FORESTS; PACIFIC-NORTHWEST; CONIFEROUS FORESTS; TROPICAL FORESTS; AIRBORNE LIDAR; LASER; BIOMASS; VOLUME; VEGETATION AB Scanning lidar remote sensing systems have recently become available for use in ecological applications. Unlike conventional microwave and optical sensors, lidar sensors directly measure the distribution of vegetation material along the vertical axis and can be used to provide three-dimensional, or volumetric, characterizations of vegetation structure. Ecological applications of scanning lidar have hitherto used one-dimensional indices to characterize canopy height. A novel three-dimensional analysis of lidar waveforms was developed to characterize the total volume and spatial organization of vegetation material and empty space within the forest canopy. These aspects of the physical structure of canopies have been infrequently measured, from either field or remote methods. We applied this analysis to 22 plots in Douglas-fir/western hemlock stands on the west slope of the Cascades Range in Oregon. Each plot had coincident lidar data and field measurements of stand structure. We compared results from the novel analysis to two earlier methods of canopy description. Using the indices of canopy structure from all three methods of description as independent variables in a stepwise multiple regression, we were able to make nonasymptotic predictions of biomass and leaf area index (LAI) over a wide range, up to 1200 Mg ha(-1) of biomass and art LAI of 12, with 90% and 75% of variance explained respectively. Furthermore, we were able to make accurate estimates of other stand structure attributes, including the mean and standard deviation of diameter at breast height, the number of steins greater than 100 cm in diameter and independent estimates of the basal area of Douglas-fir and western hemlock. These measurements can be directly related to indices of forest stand structural complexity, such as those developed for old-growth forest characterisation. Indices of canopy structure developed using the novel, three-dimensional analysis accounted for most of the variables used in predictive equations generated by the stepwise multiple regression. Published by Elsevier Science Inc. C1 US Forest Serv, USDA, Pacific NW Res Stn, Forestry Sci Lab, Corvallis, OR 97331 USA. Oregon State Univ, Dept Forest Sci, Forestry Sci Lab, Corvallis, OR 97331 USA. NASA, Goddard Space Flight Ctr, Terr Phys Lab, Greenbelt, MD 20771 USA. Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. RP Lefsky, MA (reprint author), US Forest Serv, USDA, Pacific NW Res Stn, Forestry Sci Lab, 3200 SW Jefferson Way, Corvallis, OR 97331 USA. RI Lefsky, Michael/A-7224-2009; Harding, David/F-5913-2012; OI Parker, Geoffrey/0000-0001-7055-6491 NR 76 TC 433 Z9 471 U1 22 U2 150 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD DEC PY 1999 VL 70 IS 3 BP 339 EP 361 DI 10.1016/S0034-4257(99)00052-8 PG 23 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 266JF UT WOS:000084296300009 ER PT J AU Guzman, HM Guevara, CA AF Guzman, HM Guevara, CA TI Coral reefs of Bocas del Toro, Panama: III Distribution, structure, diversity and conservation status of reefs in Pastores, Cristobal, Popa and Cayo Agua islands SO REVISTA DE BIOLOGIA TROPICAL LA Spanish DT Article DE biodiversity; coral reefs; marine conservation; marine protected areas; Caribbean; reef assessment; paper park; Bocas del Toro ID SPECIES RICHNESS; COMMUNITY STRUCTURE; EUTROPHICATION; SEDIMENTATION; MANAGEMENT; RESERVES; HOTSPOTS AB Previous studies reported low coral diversity and poor reef development inside the marine protected area of Isla Bastimentos (PNMIB), and it was recommended to widen the survey further east into other areas of the archipelago of Bocas del Toro. This study describes reef distribution, structure and status in 24 reefs along ca. 107 km of coastline in Pastores, Cristobal, Popa and Agua islands. We define for the first time the main center of diversity or "hot spot" zone for important sessile reef-building organisms. Coral diversity increases to 57 species for the archipelago (89% of Panama), adding up to 64 records for the country. There was also an increase to 29 and 53 species for octocorals and sponges, respectively. For local diversity, 96%, 94% and 97% of the total number of coral, octocoral and sponge species, respectively, are recorded inside the "hot spot." Based on our results, we recommend the modification of the existing limit of the PNMIB to include reef areas with highest diversity and abundance of threatening species (e.g. Acropora palmata, A. cervicornis), or the creation of a network of marine protected areas within the archipelago. C1 Smithsonian Inst, Smithsonian Trop Res Inst, Washington, DC 20560 USA. RP Guzman, HM (reprint author), Smithsonian Inst, Smithsonian Trop Res Inst, Washington, DC 20560 USA. NR 41 TC 26 Z9 27 U1 1 U2 9 PU REVISTA DE BIOLOGIA TROPICAL PI SAN JOSE PA UNIVERSIDAD DE COSTA RICA CIUDAD UNIVERSITARIA, SAN JOSE, COSTA RICA SN 0034-7744 J9 REV BIOL TROP JI Rev. Biol. Trop. PD DEC PY 1999 VL 47 IS 4 BP 659 EP 676 PG 18 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 326TU UT WOS:000087753500002 ER PT J AU Cornell, J AF Cornell, J TI Report: Second World Conference of Science journalists meets in Budapest SO SCIENCE COMMUNICATION LA English DT Editorial Material AB The Second World Conference of Science Journalists was held 2-4 July 1999 in Budapest, Hungary, as a satellite conference to the World Conference on Science just preceding it. Following is a report on the conference by a member of the international organizing committee. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Cornell, J (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM jcornell@cfa.harvard.edu NR 0 TC 1 Z9 1 U1 0 U2 0 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 USA SN 1075-5470 J9 SCI COMMUN JI Sci. Commun. PD DEC PY 1999 VL 21 IS 2 BP 200 EP 202 DI 10.1177/1075547099021002011 PG 3 WC Communication SC Communication GA 262QU UT WOS:000084078600011 ER PT J AU Lenz, DD DeLuca, EE Golub, L Rosner, R Bookbinder, JA Litwin, C Reale, F Peres, G AF Lenz, DD DeLuca, EE Golub, L Rosner, R Bookbinder, JA Litwin, C Reale, F Peres, G TI Long-lived coronal loop profiles from TRACE SO SOLAR PHYSICS LA English DT Article ID TRANSITION REGION; SOLAR; TEMPERATURE; EXPLORER; MODEL AB An initial study of long-lived loops observed with TRACE (Lenz et al., 1999) shows that they have no significant temperature stratification and that they are denser than the classic loop model predicts. Models that agree better with the observations include a loop consisting of a bundle of filaments at different temperatures and a loop with momentum input by MHD waves. Some implications for coronal heating models and mechanisms are discussed. C1 Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Univ Palermo, Dipartimento Sci Fis & Astron, Sez Astron, I-90134 Palermo, Italy. RP Univ Chicago, Dept Astron & Astrophys, 5640 S Ellis Ave, Chicago, IL 60637 USA. EM lenz@oddjob.uchicago.edu; edeluca@cfa.harvard.edu; lgolub@cfa.harvard.edu; rrosner@oddjob.uchicago.edu; jbookbinder@cfa.harvard.edu; litwin@oddjob.uchicago.edu; reale@oapa.astropa.unipa.it; peres@oapa.astropa.unipa.it RI DeLuca, Edward/L-7534-2013; OI DeLuca, Edward/0000-0001-7416-2895; Reale, Fabio/0000-0002-1820-4824 NR 17 TC 20 Z9 20 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 DEC PY 1999 VL 190 IS 1-2 BP 131 EP 138 DI 10.1023/A:1005209616355 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 316RP UT WOS:000087182100009 ER PT J AU Warren, HP AF Warren, HP TI Measuring the physical properties of the solar corona: Results from SUMER/SOHO and TRACE SO SOLAR PHYSICS LA English DT Article ID TRANSITION REGION; UPPER-ATMOSPHERE; ATOMIC DATABASE; EMISSION-LINES; QUIET-SUN; SOHO; SPECTRA; SPECTROMETER; INSTRUMENT; TELESCOPE AB Using SUMER observations taken above the limb of a quiet region we derive electron temperatures, emission measures, and absolute elemental abundances. This analysis, which uses recently published ionization balance calculations and the latest solar photospheric abundances, indicates that the low-FIP elements are enriched by a factor of 2.3 +/- 0.7 in the corona, which is smaller than some previous measurements. TRACE observations of this region yield systematically lower temperatures and emission measures. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Warren, HP (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St MS 58, Cambridge, MA 02138 USA. NR 28 TC 37 Z9 37 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PD DEC PY 1999 VL 190 IS 1-2 BP 363 EP 377 DI 10.1023/A:1005289726676 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 316RP UT WOS:000087182100023 ER PT J AU Li, X Habbal, SR AF Li, X Habbal, SR TI Ion cyclotron waves, instabilities and solar wind heating SO SOLAR PHYSICS LA English DT Article ID PROTON TEMPERATURE ANISOTROPY; HEAVY-IONS; VELOCITY DISTRIBUTIONS; RESONANT ACCELERATION; MAGNETIC-FIELD; CORONA; DISPERSION; MINIMUM; 0.3-AU; MODEL AB The effect of alpha particles on the dispersion relation of ion cyclotron waves and its influence on the heating of the solar wind plasma are investigated. The presence of alpha particles can dramatically change the dispersion relation of ion cyclotron waves, and significantly influence the way that ion cyclotron waves heat the solar wind plasma. We find that a spectrum of ion cyclotron waves affects the thermal anisotropy of the solar wind protons and other ions differently in interplanetary space: When alpha particles have a speed u(alpha) > 0.5v(A), and both protons and alpha particles have a thermal anisotropy T-perpendicular to/T-parallel to > 1, ion cyclotron waves heat protons in the direction perpendicular to the magnetic field, cool them in the parallel direction, and exert the opposite effect on alpha particles. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Li, X (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 38 TC 22 Z9 22 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PD DEC PY 1999 VL 190 IS 1-2 BP 485 EP 497 DI 10.1023/A:1005288832535 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 316RP UT WOS:000087182100030 ER PT J AU Steppan, SJ Akhverdyan, MR Lyapunova, EA Fraser, DG Vorontsov, NN Hoffmann, RS Braun, MJ AF Steppan, SJ Akhverdyan, MR Lyapunova, EA Fraser, DG Vorontsov, NN Hoffmann, RS Braun, MJ TI Molecular phylogeny of the marmots (Rodentia : Sciuridae): Tests of evolutionary and biogeographic hypotheses SO SYSTEMATIC BIOLOGY LA English DT Article DE Beringia; cytochrome b; Holarctic; hypothesis testing; Marmota; phylogenetics ID DNA-SEQUENCES; GENE TREES; SOCIALITY; DYNAMICS; MAMMALS; FITNESS; CONTACT; ORIGIN; SITES; ZONE AB There are 14 species of marmots distributed across the Holarctic, and despite extensive systematic study, their phylogenetic relationships remain largely unresolved. In particular, comprehensive studies have been lacking. A well-supported phylogeny is needed to place the numerous ecological and behavioral studies on marmots in an evolutionary context. To address this situation, we obtained complete cytochrome (cyt) b sequences for 13 of the species and a partial sequence for the 14th. We applied a statistical approach to both phylogeny estimation and hypothesis testing, using parsimony and maximum likelihood-based methods. We conducted statistical tests on a suite of previously proposed hypotheses of phylogenetic relationships and biogeographic histories. The cyt b data strongly support the monophyly of Marmota and a western montane clade in the Nearctic. Although some other scenarios cannot be rejected, the results are consistent with an initial diversification in North America, followed by an invasion and subsequent rapid diversification in the Palearctic. These analyses reject the two major competing hypotheses of M. broweri's phylogenetic relationships-namely, that it is the sister species to M. camtschatica of eastern Siberia, and that it is related closely to M. caligata of the Nearctic. The Alaskan distribution of M. broweri is best explained as a reinvasion from the Palearctic, but a Nearctic origin can not be rejected. Several other conventionally recognized species groups can also be rejected. Social evolution has been homoplastic, with large colonial systems evolving in two groups convergently. The cyt b data do not provide unambiguous resolution of several basal nodes in the Palearctic radiation, leaving some aspects of pelage and karyotypic evolution equivocal. C1 Smithsonian Inst, Lab Mol Systemat, Suitland, MD 20746 USA. Smithsonian Inst, Natl Museum Nat Hist, Dept Vertebrate Zool, Washington, DC 20560 USA. Natl Acad Sci Republ Armenia, Inst Zool, Yerevan 375410, Armenia. Russian Acad Sci, Inst Dev Biol, Moscow, Russia. RP Steppan, SJ (reprint author), Florida State Univ, Dept Biol Sci, B-157, Tallahassee, FL 32306 USA. RI Rohlf, F/A-8710-2008; Lyapunova, Elena/A-4696-2016 NR 63 TC 89 Z9 107 U1 0 U2 24 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 1063-5157 J9 SYST BIOL JI Syst. Biol. PD DEC PY 1999 VL 48 IS 4 BP 715 EP 734 PG 20 WC Evolutionary Biology SC Evolutionary Biology GA 334KE UT WOS:000088185000002 PM 12066297 ER PT J AU Cantino, PD Bryant, HN De Queiroz, K Donoghue, MJ Eriksson, T Hillis, DM Lee, MSY AF Cantino, PD Bryant, HN De Queiroz, K Donoghue, MJ Eriksson, T Hillis, DM Lee, MSY TI Species names in phylogenetic nomenclature SO SYSTEMATIC BIOLOGY LA English DT Article DE phylogenetic nomenclature; species names; binomial nomenclature ID TAXON NAMES; CROWN CLADES; DEFINITION; CLASSIFICATION; STABILITY; SEQUENCES; MAMMALIA; SYSTEM AB Linnaean binomial nomenclature is logically incompatible with the phylogenetic nomenclature of de Queiroz and Gauthier (1992, Annu. Rev. Ecol. Syst. 23:449-480): The former is based on the concept of genus, thus making this rank mandatory, while the latter is based on phylogenetic definitions and requires the abandonment of mandatory ranks. Thus, if species are to receive names under phylogenetic nomenclature, a different method must be devised to name them. Here, 13 methods for naming species in the context of phylogenetic nomenclature are contrasted with each other and with Linnaean binomials. A fundamental dichotomy among the proposed methods distinguishes those that retain the entire binomial of a preexisting species name from those that retain only the specific epithet. Other relevant issues include the stability, uniqueness, and ease of pronunciation of species names; their capacity to convey phylogenetic information; and the distinguishability of species names that are governed by a code of phylogenetic nomenclature both from clade names and from species namer, governed by the current codes. No method is ideal. Each has advantages and drawbacks, and preference for one option over another will be influenced by one's evaluation of the relative importance of the pros and cons for each. Moreover, sometimes the same feature is viewed as an advantage by some and a drawback by others. Nevertheless, all of the proposed methods for naming species in the context of phylogenetic nomenclature provide names that are more stable than Linnaean binomials. C1 Ohio Univ, Dept Environm & Plant Biol, Athens, OH 45701 USA. Royal Saskatchewan Museum, Regina, SK S4P 3V7, Canada. Smithsonian Inst, Natl Museum Nat Hist, Dept Vertebrate Zool, Washington, DC 20560 USA. Harvard Univ Hebaria, Cambridge, MA 02138 USA. Royal Swedish Acad Sci, Bergius Fdn, S-10405 Stockholm, Sweden. Univ Texas, Sch Biol Sci, Sect Integrat Biol, Austin, TX 78712 USA. Univ Queensland, Dept Zool, Brisbane, Qld 4072, Australia. RP Cantino, PD (reprint author), Ohio Univ, Dept Environm & Plant Biol, Athens, OH 45701 USA. RI Hillis, David/B-4278-2008 NR 45 TC 87 Z9 91 U1 4 U2 13 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 1063-5157 J9 SYST BIOL JI Syst. Biol. PD DEC PY 1999 VL 48 IS 4 BP 790 EP 807 PG 18 WC Evolutionary Biology SC Evolutionary Biology GA 334KE UT WOS:000088185000005 PM 12066299 ER PT J AU Funk, VA Cannatella, D AF Funk, VA Cannatella, D TI The Society of Systematic Biologists' Awards in systematics SO SYSTEMATIC BIOLOGY LA English DT Article C1 Smithsonian Inst, Dept Bot, Washington, DC 20560 USA. Univ Texas, Texas Mem Museum, Austin, TX USA. RP Funk, VA (reprint author), Smithsonian Inst, Dept Bot, Washington, DC 20560 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 1063-5157 J9 SYST BIOL JI Syst. Biol. PD DEC PY 1999 VL 48 IS 4 BP 832 EP 837 PG 6 WC Evolutionary Biology SC Evolutionary Biology GA 334KE UT WOS:000088185000009 ER PT J AU Lopez, OR Kursar, TA AF Lopez, OR Kursar, TA TI Flood tolerance of four tropical tree species SO TREE PHYSIOLOGY LA English DT Article DE Calophyllum longifolium; floodplains; Gustavia superba; monodominance; Panama; Prioria copaifera; root growth; seasonality; tropical forests; Virola surinamensis ID POSTANOXIC INJURY; RAIN-FORESTS; SEEDLINGS; GROWTH; PATTERNS; RESPONSES; SURVIVAL; ROOTS; PHOTOSYNTHESIS; MECHANISMS AB Many seasonally flooded habitats in the tropics are dominated by one or a few tree species. We tested the hypothesis that the inability to tolerate flooding restricts most species from becoming established in flood-prone habitats. We compared morphological and physiological responses to flooding in seedlings of Prioria copaifera Griseb., a species that farms monodominant stands in seasonally flooded habitats, and in three species confined to flood-free sites; namely Calophyllum longifolium Willd., Virola surinamensis Aubl. and Gustavia superba (H.B.K.) Berg. Flooding reduced photosynthesis at Day 45 in all species by 10-30%. By Day 90, photosynthesis returned to the control rate in Prioria, but not in the other species. Flooding reduced stomatal conductance by 25-35% in all species except Calophyllum, and it reduced leaf area growth by 44% in Virola, but not in the other species. All species survived 90 days of flooding without mortality, leaf chlorosis, leaf necrosis, or leaf abscission. Flooding reduced root:shoot ratio significantly in Gustavia and Calophyllum, but not in the other species, and it reduced maximum root depth by 29% in Prioria, but by 61% or more in the species from flood-free habitats. C1 Univ Utah, Dept Biol, Salt Lake City, UT 84112 USA. Smithsonian Trop Res Inst, Panama City, Panama. RP Lopez, OR (reprint author), Univ Utah, Dept Biol, Salt Lake City, UT 84112 USA. NR 51 TC 46 Z9 51 U1 0 U2 9 PU HERON PUBLISHING PI VICTORIA PA 202, 3994 SHELBOURNE ST, VICTORIA, BC V8N 3E2, CANADA SN 0829-318X J9 TREE PHYSIOL JI Tree Physiol. PD DEC PY 1999 VL 19 IS 14 BP 925 EP 932 PG 8 WC Forestry SC Forestry GA 263KT UT WOS:000084124400003 ER PT J AU Leigh, EG AF Leigh, EG TI The modern synthesis, Ronald Fisher and creationism SO TRENDS IN ECOLOGY & EVOLUTION LA English DT Article ID EVOLUTIONARY SYNTHESIS; ADAPTATION; GENETICS AB The 'modern evolutionary synthesis' convinced most biologists that natural selection was the only directive influence on adaptive evolution. Today, however, dissatisfaction with the synthesis is widespread, and creationists and antidarwinians are multiplying. The central problem with the synthesis is its failure to show (or to provide distinct signs) that natural selection of random mutations could account for observed levels of adaptation. C1 Smithsonian Inst, Smithsonian Trop Res Inst, Washington, DC 20560 USA. RP Leigh, EG (reprint author), Smithsonian Inst, Smithsonian Trop Res Inst, Washington, DC 20560 USA. NR 44 TC 10 Z9 10 U1 0 U2 5 PU ELSEVIER SCIENCE LONDON PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 0169-5347 J9 TRENDS ECOL EVOL JI Trends Ecol. Evol. PD DEC PY 1999 VL 14 IS 12 BP 495 EP 498 DI 10.1016/S0169-5347(99)01725-5 PG 4 WC Ecology; Evolutionary Biology; Genetics & Heredity SC Environmental Sciences & Ecology; Evolutionary Biology; Genetics & Heredity GA 253CU UT WOS:000083539700016 ER PT J AU Rasmussen, PC AF Rasmussen, PC TI A new species of hawk-owl Ninox from North Sulawesi, Indonesia SO WILSON BULLETIN LA English DT Article AB A distinctive new species of hawk-owl, Ninox ios, is described from a specimen collected in 1985 in forest at 1120 m in Bogani Nani Wartabone (then Dumoga-Bone) National Park, North Sulawesi, Indonesia. It was previously identified as a rufous morph of the Ochre-bellied Hawk-Owl, N. ochracea. Ninox ios is small, predominantly bright chestnut, and lacks facial patterning; it has pink orbital skin, yellow irides, triangular whitish scapular spots, a finely banded and relatively long tail, unusually short, slender tarsi that are feathered for most of their length, and weak claws. Its relationships within the genus Ninox are unclear; it differs in several morphological characters from all other species. Because Ninox ios is only known from one specimen, its distribution and conservation status are unknown; nothing is known of its ecology, but it probably occurs primarily at higher elevations than N. ochracea. C1 Smithsonian Inst, Washington, DC 20560 USA. Michigan State Univ Museum, E Lansing, MI 48824 USA. RP Rasmussen, PC (reprint author), Smithsonian Inst, NHB 336 MRC 114, Washington, DC 20560 USA. NR 14 TC 11 Z9 15 U1 0 U2 1 PU WILSON ORNITHOLOGICAL SOC PI ANN ARBOR PA MUSEUM OF ZOOLOGY UNIV MICHIGAN, ANN ARBOR, MI 48109 USA SN 0043-5643 J9 WILSON BULL JI Wilson Bull. PD DEC PY 1999 VL 111 IS 4 BP 457 EP + PG 9 WC Ornithology SC Zoology GA 267KK UT WOS:000084357000001 ER PT J AU Chrost, RJ Faust, MA AF Chrost, RJ Faust, MA TI Consequences of solar radiation on bacterial secondary production and growth rates in subtropical coastal water (Atlantic Coral Reef off Belize, Central America) SO AQUATIC MICROBIAL ECOLOGY LA English DT Article DE bacterial production; bacterial growth rates; solar radiation; subtropical coastal waters ID DISSOLVED ORGANIC-CARBON; UV-B RADIATION; PLANKTONIC MARINE-BACTERIA; ULTRAVIOLET-RADIATION; PHOTOCHEMICAL DEGRADATION; AQUATIC ENVIRONMENTS; SURFACE WATERS; NATURAL-WATERS; DNA-DAMAGE; BACTERIOPLANKTON AB This study reports the effects of natural solar radiation on production and growth rates of bacterial assemblages in coastal surface water of the Atlantic Barrier Coral Reef off Belize, Central America. Bacterial production rates measured in the late afternoon were significantly lower than rates measured in the morning. There were also significant differences in the specific growth rates of bacterial assemblages between water samples: bacteria grew faster, i.e. displayed shorter doubling times, in the early morning. Bioassay experiments showed a significant increase in rates of bacterial secondary production in water samples exposed in situ to ambient solar radiation at the water surface. There was also a pronounced increase in the growth rates and cell volumes of bacteria grown in sunlight-irradiated water samples. We suggest that enhanced metabolism of bacteria grown in water samples that were previously exposed to solar radiation was due mainly to photodegradation of dissolved organic matter and subsequent enrichment of water with easily utilizable substrates. The results of these studies indicate that solar radiation can directly alter bacterial production and growth over diel cycles in subtropical waters. These physico-chemical and biological interactions between solar radiation and heterotrophic bacteria in subtropical coastal water may have important biogeochemical implications at both the ecosystem and global levels. C1 Univ Warsaw, Microbial Ecol Dept, PL-00324 Warsaw 64, Poland. Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, Suitland, MD 20746 USA. RP Chrost, RJ (reprint author), Univ Warsaw, Microbial Ecol Dept, Karowa 18, PL-00324 Warsaw 64, Poland. NR 72 TC 15 Z9 16 U1 2 U2 4 PU INTER-RESEARCH PI OLDENDORF LUHE PA NORDBUNTE 23, D-21385 OLDENDORF LUHE, GERMANY SN 0948-3055 J9 AQUAT MICROB ECOL JI Aquat. Microb. Ecol. PD NOV 30 PY 1999 VL 20 IS 1 BP 39 EP 48 DI 10.3354/ame020039 PG 10 WC Ecology; Marine & Freshwater Biology; Microbiology SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Microbiology GA 264KT UT WOS:000084181800005 ER PT J AU Condit, R Ashton, PS Manokaran, N LaFrankie, JV Hubbell, SP Foster, RB AF Condit, R Ashton, PS Manokaran, N LaFrankie, JV Hubbell, SP Foster, RB TI Dynamics of the forest communities at Pasoh and Barro Colorado: comparing two 50-ha plots SO PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES LA English DT Article DE tropical forest dynamics; tree demography; Pasoh; Barro Colorado Island ID SHORT-TERM DYNAMICS; NEOTROPICAL FOREST; TROPICAL FORESTS; PANAMA; TREE; MORTALITY; DROUGHT; IMPACT; LITTER; GAP AB Dynamics of the Pasoh forest in Peninsular Malaysia were assessed by drawing a comparison with a forest in Panama, Central America, whose dynamics have been thoroughly described. Census plots of 50 ha were established at both sites using standard methods. Tree mortality at Pasoh over an eight-year interval was 1.46% yr(-1) for all stems greater than or equal to 10 mm diameter at breast height (dbh), and 1.48% yr(-1) for stems greater than or equal to 100 mm dbh. Comparable figures at the Barro Colorado Island site in Panama (BCI) were 2.55% and 2.03%. Growth and recruitment rates were likewise considerably higher at BCI than at Pasoh. For example, in all trees 500-700 mm in dbh, mean BCI growth over the period 1985-1995 was 6 mm yr(-1) whereas mean Pasoh growth was about 3.5 mm yr(-1). Examining growth and mortality rates for individual species showed that the difference between the forests can be attributed to a few light-demanding pioneer species at BCI, which have very high growth and mortality; Pasoh is essentially lacking this guild. The bulk of the species in the two forests are shade-tolerant and have very similar mortality growth and recruitment. The Pasoh forest is more stable than BCI's in another way as well: few of its tree populations changed much over the eight-year census interval. In contrast, at BCI, over 10% of the species had populations increasing or decreasing at a rate of > 0.05 yr(-1) (compared to just 2% of the species at Pasoh). The faster species turnover at BCI can probably be attributed to severe droughts that have plagued the forest periodically over the past 30 years; Pasoh has not suffered such extreme events recently. The dearth of pioneer species at Pasoh is associated with low-nutrient soil and slow litter breakdown, but the exact mechanisms behind this association remain poorly understood. C1 Smithsonian Trop Res Inst, Ctr Trop Forest Sci, Unit 0948, Miami, FL 34002 USA. Harvard Univ, Inst Int Dev, Cambridge, MA 02138 USA. Harvard Univ, Arnold Arboretum, Cambridge, MA 02138 USA. Forest Res Inst Malaysia, Kuala Lumpur 52109, Malaysia. Nanyang Technol Univ, Natl Inst Educ, Ctr Trop Forest Sci, Singapore 1025, Singapore. Princeton Univ, Dept Ecol Evolut & Behav, Princeton, NJ 08544 USA. Field Museum Nat Hist, Dept Bot, Chicago, IL 60605 USA. RP Condit, R (reprint author), Smithsonian Trop Res Inst, Ctr Trop Forest Sci, Unit 0948, APO, Miami, FL 34002 USA. EM rick@eno.princeton.edu NR 27 TC 117 Z9 142 U1 7 U2 32 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 0962-8436 J9 PHILOS T R SOC B JI Philos. Trans. R. Soc. B-Biol. Sci. PD NOV 29 PY 1999 VL 354 IS 1391 BP 1739 EP 1748 DI 10.1098/rstb.1999.0517 PG 10 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 263DY UT WOS:000084108800003 PM 11605618 ER PT J AU Qiu, YL Lee, JH Bernasconi-Quadroni, F Soltis, DE Soltis, PS Zanis, M Zimmer, EA Chen, ZD Savolainen, V Chase, MW AF Qiu, YL Lee, JH Bernasconi-Quadroni, F Soltis, DE Soltis, PS Zanis, M Zimmer, EA Chen, ZD Savolainen, V Chase, MW TI The earliest angiosperms: evidence from mitochondrial, plastid and nuclear genomes SO NATURE LA English DT Article ID INFERRING COMPLEX PHYLOGENIES; NUCLEOTIDE-SEQUENCES; GENE RBCL; ORIGIN; PLANTS; POLLEN AB Angiosperms have dominated the Earth's vegetation since the mid-Cretaceous (90 million years ago)(1), providing much of our food, fibre, medicine and timber, yet their origin and early evolution have remained enigmatic for over a century(2-8). One part of the enigma lies in the difficulty of identifying the earliest angiosperms; the other involves the uncertainty regarding the sister group of angiosperms among extant and fossil gymnosperms. Here we report a phylogenetic analysis of DNA sequences of five mitochondrial, plastid and nuclear genes (total aligned length 8,733 base pairs), from all basal angiosperm and gymnosperm lineages (105 species, 103 genera and 63 families). Our study demonstrates that Amborella, Nymphaeales and Illiciales-Trimeniaceae-Austrobaileya represent the first stage of angiosperm evolution, with Amborella being sister to all other angiosperms. We also show that Gnetales are related to the conifers and are not sister to the angiosperms, thus refuting the Anthophyte Hypothesis(1). These results have far-reaching implications for our understanding of diversification, adaptation, genome evolution and development of the angiosperms. C1 Univ Zurich, Inst Systemat Bot, CH-8008 Zurich, Switzerland. Washington State Univ, Sch Biol Sci, Pullman, WA 99164 USA. Smithsonian Inst, Lab Mol Systemat, Washington, DC 20560 USA. Royal Bot Gardens, Jodrell Lab, Richmond TW9 3DS, Surrey, England. RP Qiu, YL (reprint author), Univ Zurich, Inst Systemat Bot, Zollikerstr 107, CH-8008 Zurich, Switzerland. RI Chase, Mark /A-6642-2011; Zimmer, Elizabeth/G-3890-2011; Soltis, Pamela/L-5184-2015 NR 32 TC 585 Z9 633 U1 16 U2 90 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD NOV 25 PY 1999 VL 402 IS 6760 BP 404 EP 407 DI 10.1038/46536 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 259VA UT WOS:000083913600054 PM 10586879 ER PT J AU Srygley, RB Ellington, CP AF Srygley, RB Ellington, CP TI Estimating the relative fitness of local adaptive peaks: the aerodynamic costs of flight in mimetic passion-vine butterflies Heliconius SO PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES LA English DT Article DE locomotor mimicry; behaviour; biomechanics; coexistence; mutualism; energetics ID HOVERING INSECT FLIGHT; NEOTROPICAL BUTTERFLIES; POWER REQUIREMENTS; NATURAL-SELECTION; MIMICRY; KINEMATICS; MASS AB In a related paper, we demonstrated that mimetic Heliconius butterflies have converged in wing-beat frequency and degree of asymmetry in the wing motion, whereas sister species are dissimilar in these same traits. Warning signals of sympatric, distasteful species converge in evolutionary models in order to educate their predators more efficiently that the signal is associated with unprofitable prey. Barring other constraints, the behaviours of the different co-mimetic pairs should ultimately converge on that behaviour which minimizes the energetic cost of flight. We estimated the energetic cost of each mimic's flight behaviour in order to predict the difference in height of each fitness peak and the direction of convergent selection qualitatively. Following adjustments for body mass, mimetic Heliconius melpomene and Heliconius erato required more aerodynamic power than Heliconius cydno and Heliconius sapho. This difference was attributed to the slower flight speeds and higher wing-beat frequencies of H. melpomene and H. erato. Consequently, H. melpomene and H, erato expended more energy per unit distance per unit body mass than H. cydno and H. saaho. However, differences in body mass may equalize energy budgets and stabilize the sympatric coexistence of the two pairs of co-mimics. C1 Univ Oxford, Dept Zool, Oxford OX1 3PS, England. Smithsonian Trop Res Inst, Balboa, Panama. Univ Cambridge, Dept Zool, Cambridge CB2 3EJ, England. RP Srygley, RB (reprint author), Univ Oxford, Dept Zool, S Parks Rd, Oxford OX1 3PS, England. EM bob.srygley@zoo.ox.ac.uk NR 21 TC 13 Z9 13 U1 1 U2 10 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 0962-8452 J9 P ROY SOC B-BIOL SCI JI Proc. R. Soc. B-Biol. Sci. PD NOV 22 PY 1999 VL 266 IS 1435 BP 2239 EP 2245 PG 7 WC Biology; Ecology; Evolutionary Biology SC Life Sciences & Biomedicine - Other Topics; Environmental Sciences & Ecology; Evolutionary Biology GA 263DZ UT WOS:000084108900001 ER PT J AU Canosa, CM Worrall, DM Hardcastle, MJ Birkinshaw, M AF Canosa, CM Worrall, DM Hardcastle, MJ Birkinshaw, M TI X-ray observations of low-power radio galaxies from the B2 catalogue SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE galaxies : active; galaxies : clusters : general; X-rays : galaxies ID VLBI OBSERVATIONS; COMPLETE SAMPLE; COMA-CLUSTER; ROSAT OBSERVATIONS; VLA OBSERVATIONS; COOLING FLOWS; EMISSION; JETS; POLARIZATION; 3C-382 AB We present an analysis of X-ray data, taken with ROSAT, for a well-defined sample of low-power radio galaxies from the Bologna B2 catalogue. Where possible, the HRI has been used in order to take advantage of the high spatial resolution provided by this instrument. A variety of models are fitted to radial profiles in order to separate the resolved and unresolved X-ray emission from the galaxies. We demonstrate a strong, approximately linear, correlation between the luminosities of the unresolved X-ray components and the 5-GHz luminosities of the radio cores in this sample. This suggests a physical relationship between the soft X-ray emission of radio galaxies and the jet-generated radio core emission. We infer a nuclear jet-related origin for at least some of the X-ray emission. C1 Univ Bristol, Dept Phys, Bristol BS8 1TL, Avon, England. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Canosa, CM (reprint author), Univ Bristol, Dept Phys, Tyndall Ave, Bristol BS8 1TL, Avon, England. RI Hardcastle, Martin/E-2264-2012 OI Hardcastle, Martin/0000-0003-4223-1117 NR 64 TC 64 Z9 64 U1 0 U2 0 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. PY 1999 VL 310 IS 1 BP 30 EP 38 DI 10.1046/j.1365-8711.1999.02923.x PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 264NU UT WOS:000084189000008 ER PT J AU Nevalainen, J Markevitch, M Forman, W AF Nevalainen, J Markevitch, M Forman, W TI The baryonic and dark matter distributions in abell 401 SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology : observations; dark matter; galaxies : clusters : individual (A401); intergalactic medium; X-rays : galaxies ID X-RAY-CLUSTERS; GALAXIES; TEMPERATURE; ROSAT; GAS; MASS AB We combine spatially resolved ASCA temperature data with ROSAT imaging data to constrain the total mass distribution in the cluster A401, assuming that the cluster is in hydrostatic equilibrium, but without the assumption of gas isothermality. We obtain a total mass within the X-ray core (290 h(50)(-1) kpc) of 1.2(-0.5)(+0.1) x 10(14) h(50)(-1) M-circle dot at the 90% confidence level, 1.3 times larger than the isothermal estimate. The total mass within r(500) (1.7 h(50)(-1) Mpc) is M-500 = 0.91(-0.2)(+0.3) x 10(15) h(50)(-1) M-circle dot at 90% confidence, in agreement with the optical virial mass estimate, and 1.2 times smaller than the isothermal estimate. Our M-500 value is 1.7 times smaller than that estimated using the mass-temperature scaling law predicted by simulations. The best-fit dark matter density profile scales as r-(3.1) at large radii, which is consistent with the Navarro, Frenk & White (NFW) "universal profile" as well as the King profile of the galaxy density in A401. From the imaging data, the gas density profile is shallower than the dark matter profile, scaling r(-2.1) at large radii, leading to a monotonically increasing gas mass fraction with radius. Within r(500) asr the gas mass fraction reaches a value of f(gas) = 0.21(-0.05)(+0.06) h(50)(-3/2) (90% confidence errors). Assuming that f(gas) (plus an estimate of the stellar mass) is the universal value of the baryon fraction, we estimate the 90% confidence upper limit of the cosmological matter density to be Omega(m) < 0.31, in conflict with an Einstein-deSitter universe. Even though the NFW dark matter density profile is statistically consistent with the temperature data, its central temperature cusp would lead to convective instability at the center, because the gas density does not have a corresponding peak. One way to reconcile a cusp-shaped total mass profile with the observed gas density profile, regardless of the temperature data, is to introduce a significant nonthermal pressure in the center. Such a pressure must satisfy the hydrostatic equilibrium condition without inducing turbulence. Alternately, significant mass drop-out from the cooling flow would make the temperature less peaked and the NFW profile acceptable. However, the quality of data is not adequate to test this possibility. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Nevalainen, J (reprint author), Univ Helsinki Observ, SF-00130 Helsinki, Finland. NR 43 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 NOV 20 PY 1999 VL 526 IS 1 BP 1 EP 9 DI 10.1086/307986 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 258XA UT WOS:000083863900001 ER PT J AU Kenyon, SJ Luu, JX AF Kenyon, SJ Luu, JX TI Accretion in the early outer solar system SO ASTROPHYSICAL JOURNAL LA English DT Article DE solar system : formation; Kuiper Belt, Oort Cloud ID EDGEWORTH-KUIPER BELT; HUBBLE-SPACE-TELESCOPE; JUPITER-FAMILY COMETS; COLLISIONAL EVOLUTION; TIME SCALES; GIANT PLANET; PLANETESIMALS; OBJECTS; VELOCITY; NEBULA AB We describe calculations of the evolution of an ensemble of small planetesimals in the outer solar system. In a solar nebula with a mass of several times the minimum mass solar nebula, objects with radii of 100-1000 km can form on timescales of 10-100 Myr. Model luminosity functions derived from these calculations agree with current observations of bodies beyond the orbit of Neptune (Kuiper Belt objects). New surveys with current and planned instruments can place better constraints on the mass and dynamics of the solar nebula by measuring the luminosity function at red magnitudes, m(R) greater than or equal to 28. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Leiden Observ, NL-2300 RA Leiden, Netherlands. RP Kenyon, SJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. OI Kenyon, Scott/0000-0003-0214-609X NR 69 TC 66 Z9 67 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 NOV 20 PY 1999 VL 526 IS 1 BP 465 EP 470 DI 10.1086/308000 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 258XA UT WOS:000083863900040 ER PT J AU Winebarger, AR Emslie, AG Warren, HP AF Winebarger, AR Emslie, AG Warren, HP TI Analyzing the energetics of explosive events observed by SUMER on SOHO SO ASTROPHYSICAL JOURNAL LA English DT Article DE sun : activity; sun : transition region; sun : UV radiation ID SOLAR TRANSITION REGION; MAGNETIC RECONNECTION; FLARES; SPECTROMETER; TELESCOPE; EMISSION; CORONA; JETS; SUN AB The SUMER spectrometer on SOHO has obtained numerous observations of optically thin chromosphere-corona transition-region line profiles with high spatial, spectral, and temporal resolution. Many of these profiles exhibit asymmetries and broadenings associated with impulsive mass motions (explosive events) in the solar atmosphere. We present here a new method of analyzing non-Gaussian line profiles to calculate the distribution of fluid velocities and hence the associated energy flux. We illustrate this method through a preliminary analysis of explosive event line profiles observed by SUMER. We derive the magnitudes of the energy fluxes directed both toward and away from the observer, and their ("net flux") differences. We also identify and quantify the various components of each (i.e., kinetic, thermal and nonthermal enthalpy, and the high-energy component associated with the skewed tail of the distribution). The global energy contribution of explosive events to the solar atmosphere is then estimated under two different "grouping" assumptions. This preliminary analysis reveals an average net upward energy flux over the entire Sun of 10(4)-10(5) ergs cm(-2) s(-1), up to an order of magnitude larger than previous estimates based on characteristic velocities of the fluid. Furthermore, the global estimate for the separate upward- and downward-directed energy fluxes is 10(5)-10(6) ergs cm(-2) s(-1), which is comparable to the energy flux required for heating of the quiet corona and indicates that explosive events may indeed have significant implications for the energy balance of the chromosphere and corona. C1 Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Winebarger, AR (reprint author), Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. NR 23 TC 11 Z9 12 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 NOV 20 PY 1999 VL 526 IS 1 BP 471 EP 477 DI 10.1086/307966 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 258XA UT WOS:000083863900041 ER PT J AU Corbel, S Chapuis, C Dame, TM Durouchoux, P AF Corbel, S Chapuis, C Dame, TM Durouchoux, P TI The distance to the soft gamma repeater SGR 1627-41 SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; ISM : individual (CTB 33 G337.0-0.1); stars : individual (SGR 1627-41); stars : neutron ID SOUTHERN MILKY-WAY; MOLECULAR CLOUDS; SGR-1806-20; SGR1806-20; EMISSION; CO AB We report millimeter observations of the line of sight to the recently discovered soft gamma repeater SGR 1627-41, which has been tentatively associated with the supernova remnant (SNR) G337.0-0.1. Among the eight molecular clouds along the line of sight to SGR 1627-41, we show that SNR G337.0-0.1 is probably interacting with one of the most massive giant molecular clouds (GMCs) in the Galaxy, at a distance of 11 kpc from the Sun. Based on the high extinction to the persistent X-ray counterpart of SGR 1627-41, we present evidence for an association of this new soft gamma repeater (SGR) with the SNR G337.0-0.1; they both appear to be located on the near side of the GMC. This is the second SGR located near an extraordinarily massive GMC. We suggest that SGR 1627-41 is a neutron star with a high transverse velocity (similar to 1000 km s(-1)) escaping the young (similar to 5000 yr) SNR G337.0-0.1. C1 CEA Saclay, Serv Astrophys, F-91191 Gif Sur Yvette, France. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Corbel, S (reprint author), CEA Saclay, Serv Astrophys, F-91191 Gif Sur Yvette, France. NR 34 TC 44 Z9 44 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 NOV 20 PY 1999 VL 526 IS 1 BP L29 EP L32 DI 10.1086/312359 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 258XE UT WOS:000083864300008 ER PT J AU Jucks, KW Johnson, DG Chance, KV Traub, WA Salawitch, RJ AF Jucks, KW Johnson, DG Chance, KV Traub, WA Salawitch, RJ TI Nitric acid in the middle stratosphere as a function of altitude and aerosol loading SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ATMOS MEASUREMENTS; N2O; NITROGEN; ABUNDANCES; TRANSPORT; RADIATION; AIRCRAFT; O-3; CH4; NM AB We present remote-sensing measurements of the abundance of nitric acid (HNO3) in the lower and middle stratosphere (between 16 and 40 km) covering the period 1989-1997. The measurements were made with the Smithsonian Astrophysical Observatory Far-Infrared Spectrometer (FIRS-2) under a wide range of aerosol surface area density. We compare our measurements with the results of a photochemical steady state model to test our understanding of the chemistry of HNO3 under a variety of conditions. We find that HNO3 is significantly overestimated by the model at altitudes above 22 km, with the difference increasing with increasing altitude and decreasing aerosol surface area density. The agreement between modeled and measured HNO3 can be improved by either decreasing the rate of OH + NO2 by 35% or by using newly measured rate constants for the reactions OH + NO2 and OH + HNO3, but significant differences remain. We discuss these observations in the context of possible uncertainties in the calculated photolysis rate of HNO3 at wavelengths near 200 nm, uncertainties in the observations, errors caused by the use of constrained steady state models, and possible missing sink reactions for HNO3. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Jucks, KW (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM jucks@cfa.harvard.edu RI Salawitch, Ross/B-4605-2009; Johnson, David/F-2376-2015; OI Salawitch, Ross/0000-0001-8597-5832; Johnson, David/0000-0003-4399-5653; Chance, Kelly/0000-0002-7339-7577 NR 33 TC 17 Z9 17 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 NOV 20 PY 1999 VL 104 IS D21 BP 26715 EP 26723 DI 10.1029/1999JD900330 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 257KN UT WOS:000083781200042 ER PT J AU Ball, CD Mengel, M De Lucia, FC Woon, DE AF Ball, CD Mengel, M De Lucia, FC Woon, DE TI Quantum scattering calculations for H2S-He between 1-600 K in comparison with pressure broadening, shift, and time resolved double resonance experiments SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CORRELATED MOLECULAR CALCULATIONS; GAUSSIAN-BASIS SETS; CO-HE SYSTEM; 600 K; COLLISIONS; ATOMS; HELIUM; TEMPERATURES; PARAMETERS; HYDROGEN AB We have performed quantum scattering calculations to predict pressure broadening, pressure shift, and inelastic depopulation cross-sections for the rotational transitions 1(1,0)<-- 1(0,1) and 2(2,0)<-- 2(1,1) of the H2S molecule in collision with helium atoms over a temperature range from 1 to 600 K. The calculated cross-sections are compared with experimental values obtained by millimeter wave spectroscopic techniques and the collisional cooling method. We observe good agreement between theory and experiment over the temperature region from 20 to 600 K, but increasing differences below 20 K. Possible reasons for the deviations at lower temperatures are discussed. The calculations also illustrate the contribution of elastic collisions to the pressure broadening cross-sections. (C) 1999 American Institute of Physics. [S0021-9606(99)01143-5]. C1 Ohio State Univ, Dept Phys, Columbus, OH 43210 USA. Mol Res Inst, Mt View, CA 94043 USA. RP Ball, CD (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 36 TC 17 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 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV 15 PY 1999 VL 111 IS 19 BP 8893 EP 8903 DI 10.1063/1.480234 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 251GQ UT WOS:000083437400019 ER PT J AU Zibrov, AS Lukin, MD Scully, MO AF Zibrov, AS Lukin, MD Scully, MO TI Nondegenerate parametric self-oscillation via multiwave mixing in coherent atomic media SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTROMAGNETICALLY INDUCED TRANSPARENCY; OPTICAL INSTABILITIES; QUANTUM INTERFERENCE; SODIUM AB We demonstrate an efficient nonlinear process in which Stokes and anti-Stokes components are generated spontaneously in a multilevel medium coherently prepared by resonant, counterpropagating fields. A medium of this kind combines large nonlinear gain and efficient intrinsic feedback, thereby allowing for very weak optical fields to induce nonlinear processes. Mirrorless self-oscillation induced by microwatts of light power (nanojoules of pulse energy) is observed. C1 Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. Max Planck Inst Quantenopt, D-85748 Garching, Germany. PN Lebedev Phys Inst, Moscow 117924, Russia. RP Zibrov, AS (reprint author), Natl Inst Stand & Technol, 325 Broadway, Boulder, CO 80303 USA. RI Zibrov, Alexander/G-7419-2014 NR 30 TC 131 Z9 132 U1 2 U2 10 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 NOV 15 PY 1999 VL 83 IS 20 BP 4049 EP 4052 DI 10.1103/PhysRevLett.83.4049 PG 4 WC Physics, Multidisciplinary SC Physics GA 255NQ UT WOS:000083676400020 ER PT J AU Hardcastle, MJ Worrall, DM AF Hardcastle, MJ Worrall, DM TI ROSAT X-ray observations of 3CRR radio sources SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Review DE galaxies : active; quasars : general; X-rays : galaxies ID HIGH-RESOLUTION RADIO; FAINT LIMITING MAGNITUDES; STEEP-SPECTRUM QUASARS; ACTIVE GALACTIC NUCLEI; EARLY-TYPE GALAXIES; EMISSION-LINE GAS; COMPLETE SAMPLE; VLA OBSERVATIONS; OPTICAL IDENTIFICATIONS; CLUSTER ENVIRONMENTS AB Over half the 3CRR sample of radio galaxies and quasars has been observed in X-rays with ROSAT pointed observations, and we present results from these observations, discussing many of the sources in detail. The improved spatial resolution of ROSAT over earlier missions allows a better separation of the nuclear and extended components of the X-ray emission. We investigate the relationship between nuclear X-ray and core radio luminosity, and show that our results support a model in which every radio galaxy and quasar has a beamed nuclear soft X-ray component directly related to the radio core. We report evidence for rich cluster environments around several powerful quasars. These X-ray environments are comparable to those of high-redshift radio galaxies. C1 Univ Bristol, Dept Phys, Bristol BS8 1TL, Avon, England. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Hardcastle, MJ (reprint author), Univ Bristol, Dept Phys, Tyndall Ave, Bristol BS8 1TL, Avon, England. RI Hardcastle, Martin/E-2264-2012 OI Hardcastle, Martin/0000-0003-4223-1117 NR 138 TC 118 Z9 118 U1 0 U2 0 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 NOV 11 PY 1999 VL 309 IS 4 BP 969 EP 990 DI 10.1046/j.1365-8711.1999.02945.x PG 22 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 258KZ UT WOS:000083839500019 ER PT J AU Frenk, CS White, SDM Bode, P Bond, JR Bryan, GL Cen, R Couchman, HMP Evrard, AE Gnedin, N Jenkins, A Khokhlov, AM Klypin, A Navarro, JF Norman, ML Ostriker, JP Owen, JM Pearce, FR Pen, UL Steinmetz, M Thomas, PA Villumsen, JV Wadsley, JW Warrren, MS Xu, G Yepes, G AF Frenk, CS White, SDM Bode, P Bond, JR Bryan, GL Cen, R Couchman, HMP Evrard, AE Gnedin, N Jenkins, A Khokhlov, AM Klypin, A Navarro, JF Norman, ML Ostriker, JP Owen, JM Pearce, FR Pen, UL Steinmetz, M Thomas, PA Villumsen, JV Wadsley, JW Warrren, MS Xu, G Yepes, G TI The Santa Barbara cluster comparison project: A comparison of cosmological hydrodynamics solutions SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology : theory; dark matter; galaxies : clusters : general; large-scale structure of universe; X-rays : galaxies ID SMOOTHED PARTICLE HYDRODYNAMICS; X-RAY-CLUSTERS; FLUX-CORRECTED TRANSPORT; HIGH-RESOLUTION; GALAXY CLUSTERS; GAS-DYNAMICS; N-BODY; UNIVERSE; SIMULATION; ALGORITHM AB We have simulated the formation of an X-ray cluster in a cold dark matter universe using 12 different codes. The codes span the range of numerical techniques and implementations currently in use, including smoothed particle hydrodynamics (SPH) and grid methods with fixed, deformable, or multilevel meshes. The goal of this comparison is to assess the reliability of cosmological gasdynamical simulations of clusters in the simplest astrophysically relevant case, that in which the gas is assumed to be nonradiative. We compare images of the cluster at different epochs, global properties such as mass, temperature and X-ray luminosity, and radial profiles of various dynamical and thermodynamical quantities. On the whole, the agreement among the various simulations is gratifying, although a number of discrepancies exist. Agreement is best for properties of the dark matter and worst for the total X-ray luminosity. Even in this case, simulations that adequately resolve the core radius of the gas distribution predict total X-ray luminosities that agree to within a factor of 2. Other quantities are reproduced to much higher accuracy. For example, the temperature and gas mass fraction within the virial radius agree to within about 10%, and the ratio of specific dark matter kinetic to gas thermal energies agree to within about 5%. Various factors, including differences in the internal timing of the simulations, contribute to the spread in calculated cluster properties. Based on the overall consistency of results, we discuss a number of general properties of the cluster we have modeled. C1 Univ Durham, Dept Phys, Durham DH1 3LE, England. Max Planck Inst Astrophys, D-85740 Garching, Germany. Univ Penn, Dept Phys & Astron, Philadelphia, PA 19104 USA. Univ Toronto, Canadian Inst Theoret Astrophys, Toronto, ON M5S 3H8, Canada. Univ Toronto, Dept Astron, Toronto, ON M5S 3H8, Canada. MIT, Dept Phys, Cambridge, MA 02139 USA. Princeton Univ Observ, Princeton, NJ 08544 USA. Univ Western Ontario, Dept Phys & Astron, London, ON N6A 3K7, Canada. Univ Michigan, Dept Phys, Ann Arbor, MI 48109 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. New Mexico State Univ, Dept Astron, Las Cruces, NM 88001 USA. Univ Victoria, Dept Phys & Astron, Victoria, BC V8W 2P6, Canada. Univ Illinois, NCSA, Lab Computat Astrophys, Urbana, IL 61801 USA. Univ Illinois, Dept Astron, Urbana, IL 61801 USA. Ohio State Univ, Dept Astron, Columbus, OH 43210 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Univ Sussex, Brighton BN1 9QH, E Sussex, England. Univ Calif Santa Cruz, Board Studies Astron & Astrophys, Santa Cruz, CA 95064 USA. Univ Autonoma Madrid, Dept Fis Teor 100 11, E-28049 Madrid, Spain. RP Univ Durham, Dept Phys, Durham DH1 3LE, England. RI Pearce, Frazer/H-1503-2012; OI Warren, Michael/0000-0002-1218-7904; Evrard, August/0000-0002-4876-956X; Yepes, Gustavo/0000-0001-5031-7936 NR 56 TC 344 Z9 346 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 NOV 10 PY 1999 VL 525 IS 2 BP 554 EP 582 DI 10.1086/307908 PN 1 PG 29 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 257HP UT WOS:000083776700002 ER PT J AU Koekemoer, AM O'Dea, CP Sarazin, CL McNamara, BR Donahue, M Voit, GM Baum, SA Gallimore, JF AF Koekemoer, AM O'Dea, CP Sarazin, CL McNamara, BR Donahue, M Voit, GM Baum, SA Gallimore, JF TI The extended blue continuum and line emission around the central radio galaxy in Abell 2597 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : clusters : individual (A2597); galaxies : elliptical and lenticular, cD; galaxies : structure; radio continuum : galaxies; stars : formation ID CENTRAL CLUSTER GALAXIES; KINEMATICALLY DISTINCT CORES; HUBBLE-SPACE-TELESCOPE; RAY LUMINOUS CLUSTERS; COOLING FLOW GALAXIES; STAR-FORMATION; SURFACE PHOTOMETRY; MOLECULAR GAS; MINOR MERGERS; DARK MATTER AB We present results from detailed imaging of the centrally dominant radio elliptical galaxy in the cooling-flow cluster Abell 2597, using data obtained with the Wide Field and Planetary Camera 2 (WFPC2) on the Hubble Space Telescope (HST). This object is one of the archetypal "blue-lobed" cooling-flow radio elliptical galaxies, also displaying a luminous emission-line nebula, a compact radio source, and a significant dust lane and evidence of molecular gas in its center. We show that the radio source is surrounded by a complex network of emission-line filaments, some of which display a close spatial association with the outer boundary of the radio lobes. We present a detailed analysis of the physical properties of ionized and neutral gas associated with the radio lobes, and show that their properties are strongly suggestive of direct interactions between the radio plasma and ambient gas. We resolve the blue continuum emission into a series of knots and clumps, and present evidence that these are most likely due to regions of recent star formation. We investigate several possible triggering mechanisms for the star formation, including direct interactions with the radio source, filaments condensing from the cooling flow, or the result of an interaction with a gas-rich galaxy, which may also have been responsible for fueling the active nucleus. We propose that the properties of the source are plausibly explained in terms of accretion of gas by the cD during an interaction with a gas-rich galaxy, which, combined with the fact that this object is located at the centre of a dense, high-pressure intracluster medium, can account for the high rates of star formation and the strong confinement of the radio source. C1 Space Telescope Sci Inst, Baltimore, MD 21218 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Virginia, Dept Astron, Charlottesville, VA 22903 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Natl Radio Astron Observ, Charlottesville, VA 22903 USA. RP Koekemoer, AM (reprint author), Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 USA. EM koekemoe@stsci.edu; odea@stsci.edu; cls7i@coma.astro.virginia.edu; brm@head-cfa.harvard.edu; donahue@stsci.edy; voit@stsci.edu; sbaum@stsci.edu; jgallimo@nrao.edu RI Donahue, Megan/B-5361-2012; OI Koekemoer, Anton/0000-0002-6610-2048 NR 87 TC 37 Z9 37 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 10 PY 1999 VL 525 IS 2 BP 621 EP 637 DI 10.1086/307911 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 257HP UT WOS:000083776700007 ER PT J AU Simpson, C Eisenhardt, P Armus, L Chokshi, A Dickinson, M Djorgovski, SG Elston, R Jannuzi, BT McCarthy, PJ Pahre, MA Soifer, BT AF Simpson, C Eisenhardt, P Armus, L Chokshi, A Dickinson, M Djorgovski, SG Elston, R Jannuzi, BT McCarthy, PJ Pahre, MA Soifer, BT TI Young stars and nonstellar emission in the aligned radio galaxy 3C 256 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : individual (3C 256); galaxies : nuclei; galaxies : photometry; galaxies : stellar ID INFRARED STANDARD STARS; LUMINOSITY DEPENDENCE; REDSHIFT; ULTRAVIOLET; SCATTERING; ALIGNMENTS; 3C-256; MODELS; LINE; DUST AB We present ground-based images of the z=1.824 radio galaxy 3C 256 in the standard BVRIJHK filters and an interference filter centered at 8800 Angstrom, a Hubble Space Telescope image in a filter dominated by Ly alpha emission (F336W), and spectra covering rest-frame wavelengths from Lya to [O III] lambda 5007. Together with published polarimetry observations, we use these to decompose the overall spectral energy distribution into nebular continuum emission, scattered quasar light, and stellar emission. The nebular continuum and scattered light together comprise half (one-third) of the V-band (K-band) light within a 4 " aperture and are responsible for the strong alignment between the optical/near-infrared light and the radio emission. The stellar emission is dominated by a population estimated to be 100-200 Myr old (assuming a Salpeter IMF) and formed in a short burst with a peak star formation rate of 1-4 x 10(3) M. yr(-1). The total stellar mass is estimated to be no mote than 2 x 10(11) M., which is far less than other luminous radio galaxies at similar redshifts, and suggests that 3C 256 will undergo further star formation or mergers. C1 Natl Astron Observ Japan, Subaru Telescope, Hilo, HI 96720 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, SIRTF Sci Ctr, Pasadena, CA 91125 USA. CALTECH, Palomar Observ, Pasadena, CA 91125 USA. Indian Inst Astrophys, Bangalore 560034, Karnataka, India. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Florida, Dept Astron, Gainesville, FL 32611 USA. Natl Opt Astron Observ, Tucson, AZ 85726 USA. Observ Carnegie Inst Washington, Pasadena, CA 91101 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Simpson, C (reprint author), Natl Astron Observ Japan, Subaru Telescope, 650 N Aohoku Pl, Hilo, HI 96720 USA. NR 64 TC 7 Z9 7 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 10 PY 1999 VL 525 IS 2 BP 659 EP 672 DI 10.1086/307926 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 257HP UT WOS:000083776700010 ER PT J AU Barth, AJ Filippenko, AV Moran, EC AF Barth, AJ Filippenko, AV Moran, EC TI Polarized broad-line emission from low-luminosity active galactic nuclei SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : nuclei; galaxies : Seyfert; polarization ID SPACE-TELESCOPE IMAGES; DWARF SEYFERT NUCLEI; H-ALPHA EMISSION; RADIO GALAXIES; ACCRETION DISK; VLBI OBSERVATIONS; COMPLETE SAMPLE; ARP 102B; SPECTROPOLARIMETRY; PHOTOIONIZATION AB In order to determine whether unified models of active galactic nuclei apply to low-luminosity objects, we have undertaken a spectropolarimetric survey of LINERs and Seyfert nuclei at the Keck Observatory. The 14 objects observed have a median Ha luminosity of 8 x 10(39) ergs s(-1), well below the typical value of similar to 10(41) ergs s(-1) for Markarian Seyfert nuclei. Polarized broad Ha emission is detected in three LINERs: NGC 315, NGC 1052, and NGC 4261. Each of these is an elliptical galaxy with a double-sided radio jet, and the emission-line polarization in each case is oriented roughly perpendicular to the jet axis, as expected for the obscuring torus model. NGC 4261 and NGC 315 are known to contain dusty circumnuclear disks, which may be the outer extensions of the obscuring tori. The detection of polarized broad-line emission suggests that these objects are nearby, low-luminosity analogs of obscured quasars residing in narrow-line radio galaxies. The nuclear continuum of the low-luminosity Seyfert 1 galaxy NGC 4395 is polarized at p = 0.67%, possibly the result of an electron-scattering region near the nucleus. Continuum polarization is detected in other objects, with a median level of p = 0.36% over 5100-6100 Angstrom, but in most cases this is likely to be the result of transmission through foreground dust. The lack of significant broad-line polarization in most type 1 LINERs is consistent with the hypothesis that we view the broad-line regions of these objects directly, rather than in scattered light. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. RP Barth, AJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM abarth@cfa.harvard.edu; alex@astro.berkeley.edu; emoran@astro.berkeley.edu NR 63 TC 72 Z9 72 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 NOV 10 PY 1999 VL 525 IS 2 BP 673 EP 684 DI 10.1086/307941 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 257HP UT WOS:000083776700011 ER PT J AU Wood, K Reynolds, RJ AF Wood, K Reynolds, RJ TI A model for the scattered light contribution and polarization of the diffuse H alpha galactic background SO ASTROPHYSICAL JOURNAL LA English DT Article DE diffuse radiation; dust, extinction; HII regions; polarization; radiative transfer ID FRACTAL INTERSTELLAR-MEDIUM; INFRARED POLARIMETRY; SPIRAL GALAXIES; RADIATION-FIELD; MAGNETIC-FIELD; IONIZED-GAS; II REGIONS; EXTINCTION; IONIZATION; EMISSION AB We present Monte Carlo simulations of the diffuse H alpha Galactic background. Our models comprise direct and multiply scattered H alpha radiation from the kpc scale height warm ionized medium and midplane H II regions. The scattering is off dust that is assumed to be well mixed with the gas, with an axisymmetric density distribution taken from the literature. The results of our simulations are all-sky H alpha images that enable us to separate out the contributions of direct and scattered radiation. We also determine how far the model H alpha photons have traveled, i.e., how far we see into the Galaxy at H alpha. Our models reproduce the overall characteristics of the observed H alpha background and predict that the scattered Ha intensity at high latitudes is in the range 5%-20% of the total intensity, in agreement with estimates based on [S II]/H alpha and [O III]/H alpha line ratio measurements. The polarization arising from dust scattering of H alpha from midplane H II regions is predicted to be less than 1% at high latitude. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Univ Wisconsin, Dept Astron, Madison, WI 53703 USA. RP Wood, K (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 39 TC 61 Z9 61 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 NOV 10 PY 1999 VL 525 IS 2 BP 799 EP 807 DI 10.1086/307939 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 257HP UT WOS:000083776700024 ER PT J AU Furuya, RS Kitamura, Y Saito, M Kawabe, R Wootten, HA AF Furuya, RS Kitamura, Y Saito, M Kawabe, R Wootten, HA TI VLA observations of H2O masers in the class 0 protostar S106 fir: Evidence for a 10 AU scale accelerating jetlike flow SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : individual (S106 FIR); ISM : jets and outflows; masers; stars : pre-main-sequence; techniques : interferometric ID LOW-MASS STARS; YOUNG STELLAR OBJECTS; WATER MASERS; BIPOLAR NEBULA; CIRCUMSTELLAR ENVIRONMENTS; MOLECULAR OUTFLOWS; PROPER MOTIONS; REGION; VLA-1623; IMAGES AB We conducted VLA observations at 0''.06 resolution of the 22 GHz water masers toward the Class 0 source S106 FIR (d = 600 pc; 15'' west of S106 IRS 4) on two epochs separated by similar to 3 months. Two compact clusters of the maser spots were found in the center of the submillimeter core of S106 FIR. The separation of the clusters was similar to 80 mas (48 AU) along P.A. = 70 degrees, and the size of each cluster was similar to 20 mas x 10 mas. The western cluster, which had three maser components, was 8.0 km s(-1) blueshifted, and the eastern cluster, which had a single component, was 7.0 km s(-1) redshifted with respect to the ambient cloud velocity. Each component was composed of a few spatially localized maser spots and was aligned on a line connecting the clusters. We found relative proper motions of the components with approximate to 30 mas yr(-1) (18 AU yr(-1)) along the line. In addition, a series of single-dish observations shows that the maser components drifted with radial accelerations of similar to 1 km s(-1) yr(-1). These facts indicate that the masers could be excited by a 10 AU scale jetlike accelerating how ejected from an assumed protostar located between the two clusters. The outflow size traced by the masers was 50 AU x 5 AU after correction for an inclination angle of 10 degrees, which was derived from the relative proper motions and radial velocities of the maser components. The three-dimensional outflow velocity ranged from 40 to 70 km s(-1) assuming symmetric proper motions for the blue and red components. Since no distinct CO molecular outflows have been detected so far, we suggest that S106 FIR is an extremely young protostar observed just after the onset of outflowing activity. C1 Grad Univ Adv Studies, Nobeyama Radio Observ, Dept Astron Sci, Nagano 3841305, Japan. Inst Space & Astronaut Sci, Sagamihara, Kanagawa 2298510, Japan. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Natl Radio Astron Observ, Charlottesville, VA 22903 USA. RP Furuya, RS (reprint author), Grad Univ Adv Studies, Nobeyama Radio Observ, Dept Astron Sci, Nobeyama 411, Nagano 3841305, Japan. EM ray@nro.nao.ac.jp NR 50 TC 32 Z9 32 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 10 PY 1999 VL 525 IS 2 BP 821 EP 831 DI 10.1086/307913 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 257HP UT WOS:000083776700026 ER PT J AU Monnier, JD Tuthill, PG Danchi, WC AF Monnier, JD Tuthill, PG Danchi, WC TI Pinwheel nebula around WR 98a SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : general; circumstellar matter; stars : mass loss; stars : variables : other stars : Wolf-Rayet; techniques : interferometric ID WOLF-RAYET STARS; LONG-PERIOD; BINARIES; DUST; CIRCULARIZATION; HD-193793; EMISSION AB We present the first near-infrared images of the dusty Wolf-Rayet star WR 98a. Aperture-masking interferometry has been utilized to recover images at the diffraction limit of the Keck I telescope, less than or similar to 50 mas at 2.2 mu m. Multiepoch observations spanning about 1 yr have resolved the dust shell into a "pinwheel" nebula, the second example of a new class of dust shell first discovered around WR 104 by Tuthill, Monnier, & Danchi. Interpreting the collimated dust outflow in terms of an interacting winds model, the binary orbital parameters and apparent wind speed are derived: a period of 565 +/- 50 days, a viewing angle of 35 degrees +/- 6 degrees from the pole, and a wind speed of 99 +/- 23 mas yr(-1). This period is consistent with a possible similar to 588 day periodicity in the infrared light curve, linking the photometric variation to the binary orbit. Important implications for binary stellar evolution are discussed by identifying WR 104 and WR 98a as members of a class of massive, short-period binaries whose orbits were circularized during a previous red supergiant phase. The current component separation in each system is similar to the diameter of a red supergiant, which indicates that the supergiant phase was likely terminated by Roche lobe overflow, leading to the present Wolf-Rayet stage. C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. RP Monnier, JD (reprint author), Smithsonian Astrophys Observ, MS 42,60 Garden St, Cambridge, MA 02138 USA. OI Monnier, John D/0000-0002-3380-3307 NR 31 TC 65 Z9 65 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 10 PY 1999 VL 525 IS 2 BP L97 EP L100 DI 10.1086/312352 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 257HQ UT WOS:000083776800008 ER PT J AU Quataert, E Di Matteo, T Narayan, R Ho, LC AF Quataert, E Di Matteo, T Narayan, R Ho, LC TI Possible evidence for truncated thin disks in the low-luminosity active galactic nuclei M81 and NGC 4579 SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; black hole physics; galaxies : individual (M81, NGC 4579) ID X-RAY-EMISSION; ACCRETION DISKS; BLACK-HOLES; TRANSITIONS; GALAXIES; FLOW; X-1 AB M81 and NGC 4579 are two of the few low-luminosity active galactic nuclei that have an estimated mass for the central black hole, detected hard X-ray emission, and detected optical/UV emission. In contrast to the canonical "big blue bump," both have optical/UV spectra that decrease with increasing frequency in a vL(v) plot. Barring significant reddening by dust and/or large errors in the black hole mass estimates, the optical/UV spectra of these systems require that the inner edge of a geometrically thin, optically thick accretion disk lies at similar to 100 Schwarzschild radii. The observed X-ray radiation can be explained by an optically thin, two-temperature, advection-dominated accretion flow at smaller radii. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Carnegie Observ, Pasadena, CA 91101 USA. RP Quataert, E (reprint author), Inst Adv Study, Sch Nat Sci, Olden Lane, Princeton, NJ 08540 USA. OI Narayan, Ramesh/0000-0002-1919-2730 NR 31 TC 81 Z9 82 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 NOV 10 PY 1999 VL 525 IS 2 BP L89 EP L92 DI 10.1086/312353 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 257HQ UT WOS:000083776800006 ER PT J AU Srygley, RB Ellington, CP AF Srygley, RB Ellington, CP TI Discrimination of flying mimetic, passion-vine butterflies Heliconius SO PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES LA English DT Article DE locomotor mimicry; behaviour; mutualism; kinematics; tropical rainforest; signal ID HAWKMOTH MANDUCA-SEXTA; MIMICRY; FLIGHT; EVOLUTION; TEMPERATURE; MORPHOLOGY; KINEMATICS; PREDATION; MECHANICS AB Wing-beat frequency and the degree of asymmetry in wing motion were more similar among mimics than among sister species of passion-vine butterflies in the genus Heliconius. Asymmetry in wing motion is not attributed to lift production, and serves as the first clear example of a mimetic behavioural signal for a flying organism. Because the similarities in wing motion are too subtle for humans to observe with the naked eye, they serve as a previously unexplored mimetic signal. C1 Univ Oxford, Dept Zool, Oxford OX1 3PS, England. Smithsonian Trop Res Inst, Balboa, Panama. Univ Cambridge, Dept Zool, Cambridge CB2 3EJ, England. RP Srygley, RB (reprint author), Univ Oxford, Dept Zool, S Parks Rd, Oxford OX1 3PS, England. EM bob.srygley@zoo.ox.ac.uk NR 25 TC 24 Z9 24 U1 1 U2 8 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 0962-8452 J9 P ROY SOC B-BIOL SCI JI Proc. R. Soc. B-Biol. Sci. PD NOV 7 PY 1999 VL 266 IS 1434 BP 2137 EP 2140 PG 4 WC Biology; Ecology; Evolutionary Biology SC Life Sciences & Biomedicine - Other Topics; Environmental Sciences & Ecology; Evolutionary Biology GA 255YD UT WOS:000083697000001 ER PT J AU Summers, K Symula, R Clough, M Cronin, T AF Summers, K Symula, R Clough, M Cronin, T TI Visual mate choice in poison frogs SO PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES LA English DT Article DE poison frogs; Dendrobatidae; colour; visual; mate choice ID DENDROBATES-PUMILIO; SEXUAL SELECTION; PARENTAL BEHAVIOR; BROOD CARE; COURTSHIP AB We investigated female mate choice on the basis of visual cues in two populations of Dendrobates pumilio, the strawberry poison frog, from the Bocas del Toro Archipelago in Panama, Central America. Mate choice experiments were carried out by presenting subject females of each of two morphs of this species (orange and green) from two different island populations (Nancy Key and Pope Island) with object frogs (one of each morph) under glass at one end of a terrarium. Recorded calls were played simultaneously from behind both object frogs. The experiments were carried out under two light regimes: (i) white light, and (ii) relatively monochromatic filtered blue light. Subject females from each population displayed a significant preference for their own morph under white light, but not under blue light. These results indicate that female D.pumilio use visual cues in mate choice, and suggest that colour may be the visual cue they use. C1 E Carolina Univ, Dept Biol, Greenville, NC 27858 USA. Smithsonian Trop Res Inst, Balboa, Panama. Univ Maryland, Dept Biol Sci, Baltimore, MD 21228 USA. RP Summers, K (reprint author), E Carolina Univ, Dept Biol, Greenville, NC 27858 USA. EM summersk@mail.ecu.edu NR 22 TC 120 Z9 124 U1 4 U2 40 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 0962-8452 J9 P ROY SOC B-BIOL SCI JI Proc. R. Soc. B-Biol. Sci. PD NOV 7 PY 1999 VL 266 IS 1434 BP 2141 EP 2145 PG 5 WC Biology; Ecology; Evolutionary Biology SC Life Sciences & Biomedicine - Other Topics; Environmental Sciences & Ecology; Evolutionary Biology GA 255YD UT WOS:000083697000002 PM 10649631 ER PT J AU Sorenson, MD Cooper, A Paxinos, EE Quinn, TW James, HF Olson, SL Fleischer, RC AF Sorenson, MD Cooper, A Paxinos, EE Quinn, TW James, HF Olson, SL Fleischer, RC TI Relationships of the extinct moa-nalos, flightless Hawaiian waterfowl, based on ancient DNA SO PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES LA English DT Article DE Anseriformes; Anatidae; molecular systematics; mitochondrial DNA; fossils; ducks ID DABBLING DUCKS TRIBE; MITOCHONDRIAL-DNA; PHYLOGENETIC ANALYSIS; EVOLUTIONARY RATES; SEQUENCE DATA; ANSERIFORMES; AVES; ANATIDAE; BIRDS; CLASSIFICATION AB The extinct moa-nalos were very large, flightless waterfowl from the Hawaiian islands. We extracted, amplified and sequenced mitochondrial DNA from fossil moa-nalo bones to determine their systematic relationships and lend insight into their biogeographical history. The closest living relatives of these massive, goose-like birds are the familiar dabbling ducks (tribe Anatini). Moa-nalos, however, are not closely related to any one extant species, but represent an ancient lineage that colonized the Hawaiian islands and evolved flightlessness long before the emergence of the youngest island, Hawaii, from which they are absent. Ancient DNA yields a novel hypothesis for the relationships of these bizarre birds, whereas the evidence of phylogeny in morphological characters was obscured by the evolutionary transformation of a small, volant duck into a giant, terrestrial herbivore. C1 Smithsonian Inst, Natl Zool Pk, Mol Genet Lab, Washington, DC 20008 USA. Univ Denver, Dept Biol Sci, Denver, CO 80208 USA. Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. RP Sorenson, MD (reprint author), Boston Univ, Dept Biol, 5 Cummington St, Boston, MA 02215 USA. EM msoren@bu.edu RI Sorenson, Michael/D-8065-2011; Cooper, Alan/E-8171-2012 OI Sorenson, Michael/0000-0001-5375-2917; Cooper, Alan/0000-0002-7738-7851 NR 44 TC 60 Z9 63 U1 1 U2 12 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 0962-8452 J9 P ROY SOC B-BIOL SCI JI Proc. R. Soc. B-Biol. Sci. PD NOV 7 PY 1999 VL 266 IS 1434 BP 2187 EP 2193 PG 7 WC Biology; Ecology; Evolutionary Biology SC Life Sciences & Biomedicine - Other Topics; Environmental Sciences & Ecology; Evolutionary Biology GA 255YD UT WOS:000083697000009 PM 10649633 ER PT J AU Ashenberg, J Lorenzini, EC AF Ashenberg, J Lorenzini, EC TI Active gravity-gradient stabilization of a satellite in elliptic orbits SO ACTA ASTRONAUTICA LA English DT Article ID ATTITUDE-CONTROL AB A tether can be utilized as an efficient actuator for the purpose of satellite attitude control. The tether tension generates a strong passive gravity stabilization effect. The combination of tether tension with a movable attachment point mechanism results in an effective and low cost active controller. This paper reviews the concept and presents the dynamical characteristics of the configuration. It then demonstrates that a feasible three-axis control can be achieved by means of only two actuators. The primary contribution is the development of a control law that works for eccentric orbits. In this case, the dynamical system that represents the configuration becomes periodic in time, and thus impossible to control by using constant gains. The solution is a periodic control law. A combination of Floquet transformation and sampled state periodic hold feedback control is proposed as an effective pointing method for small-eccentricity orbits. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Ashenberg, J (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 11 TC 10 Z9 11 U1 0 U2 3 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 NOV PY 1999 VL 45 IS 10 BP 619 EP 627 DI 10.1016/S0094-5765(99)00127-7 PG 9 WC Engineering, Aerospace SC Engineering GA 283VF UT WOS:000085296200002 ER PT J AU Wen, J Nowicke, JW AF Wen, J Nowicke, JW TI Pollen ultrastructure of Panax (the ginseng genus, araliaceae), an eastern Asian and eastern North American disjunct genus SO AMERICAN JOURNAL OF BOTANY LA English DT Article DE Aralia; Araliaceae; ginseng; Panax; pollen ultrastructure ID TRIFOLIUM ARALIACEAE; DWARF GINSENG; GENDER; MORPHOLOGY; SEQUENCES AB Pollen of ten species of Panax and six species of Aralia was examined in light microscopy and scanning and transmission electron microscopy. Grains of both genera have similar complex apertures, short columellae, and overlapping rectal sculptures, suggesting a close relationship. Most species of Panax have pollen characterized by striato-reticulate tecta, short columellae, thick foot layers, costa ectocolpi, and lalongate endoapertures. The eastern North American P. trifolius, commonly known as the dwarf ginseng, has a distinctive pollen morphology and exine structure, supporting the hypothesis of its phylogenetically isolated position. Pollen of the eastern Asian P. ginseng (ginseng) can be distinguished from the eastern North American P. quinquefolius (American ginseng) by differences in ultrastructure. The monophyly of the three medicinally important species, P. ginseng, P. notoginseng, and P. quinquefolius, suggested by triterpenoid data, is not supported by pollen data. The results of the pollen study are generally congruent with those from the sequences of nuclear ribosomal DNA. C1 Colorado State Univ, Dept Biol, Ft Collins, CO 80523 USA. Smithsonian Inst, Dept Bot, NHB 166, Washington, DC 20560 USA. RP Wen, J (reprint author), Colorado State Univ, Dept Biol, Ft Collins, CO 80523 USA. NR 39 TC 29 Z9 36 U1 1 U2 5 PU BOTANICAL SOC AMER INC PI COLUMBUS PA OHIO STATE UNIV-DEPT BOTANY 1735 NEIL AVE, COLUMBUS, OH 43210 USA SN 0002-9122 J9 AM J BOT JI Am. J. Bot. PD NOV PY 1999 VL 86 IS 11 BP 1624 EP 1636 DI 10.2307/2656799 PG 13 WC Plant Sciences SC Plant Sciences GA 257FA UT WOS:000083770800012 PM 10562253 ER PT J AU Morrow, CJ Wildt, DE Monfort, SL AF Morrow, C. J. Wildt, D. E. Monfort, S. L. TI Reproductive seasonality in the female scimitar-horned oryx (Oryx dammah) SO ANIMAL CONSERVATION LA English DT Article AB Faecal oestrogen and progestin analyses were used to assess ovarian activity in non-pregnant scimitar-horned oryx ( Oryx dammah) during a 13-month interval. Mean (+/- SE) luteal phase, interluteal phase and oestrous cycle duration were 18.8 (+/- 0.5), 5.1 (+/- 0.2) and 23.8 (+/- 1.3) days, respectively. All females exhibited a synchronized anovulatory period that ranged from 36-95 days during spring. Short ovarian cycles ( 10.6 (+/- 0.8) days) were observed intermittently throughout the year and before the spontaneous resumption of oestrous cyclicity. Periovulatory peaks in oestrogen concentrations were detected for 42.5% ( 31/73) of ovarian cycles. A parallel analysis of reproductive data from the North American studbook ( 1985-1994) revealed that captive-held scimitar-horned oryx gave birth throughout the year. Sex ratio at birth was male-biased ( 54.4%), and 19.1% of all calves failed to survive to 6 months of age ( 220 out of 1149 births). Only 0.7% of births resulted in twins. Median interbirth interval was 277 days, and 75% of these intervals were less than 332 days. Interbirth interval was extended ( P < 0.05) if parturition occurred from January through May. In summary, the scimitar-horned oryx is a seasonally polyoestrous species that experiences a distinct anovulatory period during spring in north-east America. C1 [Morrow, C. J.; Wildt, D. E.; Monfort, S. L.] Smithsonian Inst, Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA 22630 USA. [Morrow, C. J.] George Mason Univ, Fairfax, VA 22030 USA. RP Morrow, CJ (reprint author), Ruakura Agr Ctr, AgRes, Private Bag 3123, Hamilton, New Zealand. EM morrowc@agresearch.cri.nz FU Smithsonian Institution Scholarly Studies Programme; Friends of the National Zoo; Morris Animal Foundation; George Mason University FX The following North American zoos and private owners provided details of management records that made the retrospective analysis possible: Busch Gardens Zoological Park, FL; Cape May County Zoo Park, NJ; Catskill Game Farm, NY; Central Florida Zoological Park, FL; Dallas Zoo, TX; Denver Zoological Gardens, CO; Detroit Zoological Park, MI; Fossil Rim Wildlife Center, TX; Jacksonville Zoological Park, FL; Little Rock Zoological Gardens, AR; Memphis Zoological Garden, TN; Miami Metrozoo, FL; Marine World Africa USA, CA; National Zoological Park's Conservation & Research Center, VA; Omaha's Henry Doorly Zoo, NE; Paramount's Kings Dominion, VA; San Antonio Zoological Gardens, TX; San Diego Wild Animal Park, CA; San Diego Zoological Garden, CA; Selah Bamberger Ranch, TX; T. Jack Moore Ranch, TX; The Zoo, Gulf Brez, FL; White Oak Conservation Center, FL; Wildlife World Zoo, AZ; Vancouver Game Farm, BC.; We are grateful to Alan Rost and Dr Rod East for providing copies of the North American Regional Studbooks and the IUCN/SSC Antelope Survey Updates, respectively. We thank Dr Donald Gantz (George Mason University) for advice and assistance with the statistical analysis of studbook data. We gratefully acknowledge the CRC animal keeper and veterinary care staff for animal care throughout the study. The financial support of the Smithsonian Institution Scholarly Studies Programme, Friends of the National Zoo, Morris Animal Foundation and George Mason University is gratefully acknowledged. NR 45 TC 14 Z9 16 U1 1 U2 6 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 1367-9430 J9 ANIM CONSERV JI Anim. Conserv. PD NOV PY 1999 VL 2 IS 4 BP 261 EP 268 DI 10.1111/j.1469-1795.1999.tb00072.x PG 8 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA V71EJ UT WOS:000204810900004 ER PT J AU Ibata, RA Lewis, GF Irwin, MJ Lehar, J Totten, EJ AF Ibata, RA Lewis, GF Irwin, MJ Lehar, J Totten, EJ TI NICMOS and VLA observations of the gravitationally lensed ultraluminous BAL quasar APM 08279+5255: Detection of a third image SO ASTRONOMICAL JOURNAL LA English DT Article DE gravitational lensing; infrared radiation; quasars : individual (APM 08279+5255) ID GALAXY; CLUSTER AB We present a suite of observations of the recently identified ultraluminous BAL quasar APM 08279 + 5255, taken both in the infrared with the NICMOS high-resolution camera on board the Hubble Space Telescope and at 3.5 cm with the Very Large Array. With an inferred luminosity of similar to 5 x 10(15) L., APM 08279+5255 is apparently the most luminous system known. Extant ground-based images show that APM 08279+5255 is not pointlike, but is instead separated into two components, indicative of gravitational lensing. The much higher resolution images presented here also reveal two point sources, A and B, of almost equal brightness (f(B)/f(A) = 0.782 +/- 0.010), separated by 0." 378 +/- 0." 001, as well as a third, previously unknown, fainter image, C, seen between the brighter images. While the nature of C is not fully determined, several lines of evidence point to it being a third gravitationally lensed image of the quasar, rather than being the lensing galaxy. Simple models that recover the relative image configuration and brightnesses are presented. While proving to be substantially amplified, APM 08279 + 5255 possesses an intrinsic bolometric luminosity of similar to 10(14) --> 10(15) L. and remains amongst the most luminous objects known. C1 European So Observ, D-85748 Munich, Germany. Univ Victoria, Dept Phys & Astron, Victoria, BC V8W 3P6, Canada. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Keele, Dept Phys, Keele ST5 5BG, Staffs, England. RP Ibata, RA (reprint author), European So Observ, Karls Schwarzchild Str 2, D-85748 Munich, Germany. RI Lewis, Geraint/F-9069-2015 OI Lewis, Geraint/0000-0003-3081-9319 NR 25 TC 61 Z9 61 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 NOV PY 1999 VL 118 IS 5 BP 1922 EP 1930 DI 10.1086/301111 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 264LB UT WOS:000084182800003 ER PT J AU Mochejska, BJ Kaluzny, J Stanek, KZ Krockenberger, M Sasselov, DD AF Mochejska, BJ Kaluzny, J Stanek, KZ Krockenberger, M Sasselov, DD TI Direct distances to nearby galaxies using detached eclipsing binaries and cepheids. V. Variables in the field M31F SO ASTRONOMICAL JOURNAL LA English DT Article DE binaries : eclipsing; Cepheids; distance scale; galaxies : individual (M31); stars : variables : other ID CLASSICAL CEPHEIDS; COMPANIONS; SYSTEM AB We undertook a long-term project, DIRECT, to obtain the direct distances to two important galaxies in the cosmological distance ladder-M31 and M33-using detached eclipsing binaries (DEBs) and Cepheids. While rare and difficult to detect, DEBs provide us with the potential to determine these distances with an accuracy better than 5%. The extensive photometry obtained in order to detect DEBs provides us with good light curves for the Cepheid variables. These are essential to the parallel project to derive direct Baade-Wesselink distances to Cepheids in M31 and M33. For both Cepheids and eclipsing binaries, the distance estimates will be free of any intermediate steps. As a first step in the DIRECT project, between September 1996 and October 1997 we obtained 95 full/partial nights on the F. L. Whipple Observatory 1.2 m telescope and 36 full nights on the Michigan-Dartmouth-MIT 1.3 m telescope to search for DEBs and new Cepheids in the M31 and M33 galaxies. In this paper, the fifth in the series, we present the catalog of variable stars found in the held M31F [(alpha,delta)= (10 degrees 10, 40 degrees 72), J2000.0]. We have found 64 variable stars: four eclipsing binaries, 52 Cepheids and eight other periodic, possible long-period or nonperiodic variables. The catalog of variables, as well as their photometry and finding charts, is available via anonymous ftp and the World Wide Web. The complete set of the CCD frames is available upon request. C1 Warsaw Univ Observ, PL-00478 Warsaw, Poland. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. N Copernicus Astron Ctr, PL-00716 Warsaw, Poland. RP Mochejska, BJ (reprint author), Warsaw Univ Observ, Al Ujazdowskie 4, PL-00478 Warsaw, Poland. NR 36 TC 19 Z9 19 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 NOV PY 1999 VL 118 IS 5 BP 2211 EP 2228 DI 10.1086/301081 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 264LB UT WOS:000084182800022 ER PT J AU Cole, AA Wood, K Nordsieck, KH AF Cole, AA Wood, K Nordsieck, KH TI Ultraviolet imaging polarimetry of the Large Magellanic Cloud. II. Models SO ASTRONOMICAL JOURNAL LA English DT Article DE dust, extinction; ISM : structure; Magellanic Clouds; methods : numerical; polarization ID STELLAR ASSOCIATIONS; DUST; EXTINCTION; RADIATION; GALAXIES; REGIONS; GRAINS; LMC AB Motivated by new sounding-rocket wide-field polarimetric images of the Large Magellanic Cloud (reported simultaneously by Cole et al.), we have used a three-dimensional Monte Carlo radiation transfer code to investigate the escape of near-ultraviolet photons from young stellar associations embedded within a disk of dusty material (i.e., a galaxy). As photons propagate through the disk, they may be scattered or absorbed by dust. Scattered photons are polarized and tracked until they escape the dust layer, allowing them to be observed; absorbed photons heat the dust, which radiates isotropically in the far-infrared where the galaxy is optically thin. The code produces four output images: near-UV and far-IR flux, and near-UV images in the linear Stokes parameters Q and U. From these images we construct simulated UV polarization maps of the LMC. We use these maps to place constraints on the star+dust geometry of the LMC and the optical properties of its dust grains. By tuning the model input parameters to produce maps that match the observed polarization maps, we derive information about the inclination of the LMC disk to the plane of the sky and about the scattering phase function g. We compute a grid of models with i = 28 degrees, 36 degrees, and 45 degrees, and g = 0.64, 0.70, 0.77, 0.83, and 0.90. The model that best reproduces the observed polarization maps has i = 36 degrees(-5)(+2) and g approximate to 0.7. Because of the low signal-to-noise in the data, we cannot place firm constraints on the value of g. The highly inclined models do not match the observed centrosymmetric polarization patterns around bright OB associations or the distribution of polarization values. Our models approximately reproduce the observed ultraviolet photopolarimetry of the western side of the LMC; however, the output images depend on many input parameters and are nonunique. We discuss some of the limitations of the models and outline future steps to be taken; our models make some predictions regarding the polarization properties of diffuse light across the rest of the LMC. C1 Univ Wisconsin, Dept Astron, Madison, WI 53706 USA. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Univ Wisconsin, Space Astron Lab, Madison, WI 53706 USA. RP Cole, AA (reprint author), Univ Massachusetts, Dept Phys & Astron, 640 Lederle Grad Res Tower, Amherst, MA 01002 USA. OI Cole, Andrew/0000-0003-0303-3855 NR 45 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 NOV PY 1999 VL 118 IS 5 BP 2292 EP 2305 DI 10.1086/301105 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 264LB UT WOS:000084182800027 ER PT J AU Knapp, GR Dobrovolsky, SI Ivezic, Z Young, K Crosas, M Mattei, JA Rupen, MP AF Knapp, GR Dobrovolsky, SI Ivezic, Z Young, K Crosas, M Mattei, JA Rupen, MP TI The light curve and evolutionary status of the carbon star V Hya SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : mass-loss; stars : AGB and post-AGB; radio lines : stars ID SPACED DATA; RED GIANTS; HYDRAE; NEBULAE; WINDS AB V Hya, an evolved carbon star with a complex circumstellar envelope, has two variability periods, 530(d) and 6000(d) (17 years). We analyze recent light curve data and show that both variations have been present for at least 100 years and have been regular over this time. The 530d period and its 1.5(m)-2(m) amplitude show that V Hya is a Mira variable. We suggest that the star is in a binary system (as also suspected from the structure of the circumstellar envelope) and that the 17-year variation is due to extinction by circumstellar dust orbiting with the companion. The properties of the envelope found from molecular line observations: the fast molecular wind, the relatively small size of the dense circumstellar envelope, and the high mass loss rate, all suggest that V Hya has entered its 'superwind' phase. However, its spectral type, period, colors, and lack of ionizing radiation show that the star is still on the nGB. These properties add to the evidence that the complex structures of many planetary nebulae, including fast stellar winds, originate during the final phases of mass loss on the AGE. C1 Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Amer Assoc Variable Star Observers, Cambridge, MA 02128 USA. Natl Radio Astron Observ, Socorro, NM 87801 USA. RP Knapp, GR (reprint author), Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA. EM gk@astro.princeton.edu; sid@astro.princeton.edu; ivezic@astro.princeton.edu; rtm@dolson.harvard.edu; mcrosas@dolson.harvard.edu; jmatei@aavso.org; mrupen@nrao.edu NR 26 TC 28 Z9 28 U1 0 U2 1 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 NOV PY 1999 VL 351 IS 1 BP 97 EP 102 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 258JQ UT WOS:000083836400014 ER PT J AU Perola, GC Matt, G Cappi, M Dal Fiume, D Fiore, F Guainazzi, M Mineo, T Molendi, S Nicastro, F Piro, L Stirpe, G AF Perola, GC Matt, G Cappi, M Dal Fiume, D Fiore, F Guainazzi, M Mineo, T Molendi, S Nicastro, F Piro, L Stirpe, G TI X-ray spectral components from a broad band BeppoSAX observation of the Seyfert galaxy IC 4329A SO ASTRONOMY & ASTROPHYSICS LA English DT Letter DE galaxies : individual : IC 4329A; galaxies : Seyfert; X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; COLD MATTER; IC-4329A; SIGNATURES; QUASARS; LINE; BUMP AB From the spectral analysis of a broadband (0.1-200 keV) BeppoSAX observation of the Seyfert 1 galaxy IC 4329A, the main results obtained are: a) the amount of reflection, together with the intensity of the iron K line, indicate a geometry with a solid angle substantially less than 2 pi; b) the power law is affected by a cut off with e-folding energy about 270 keV, the fourth individual object so far where this property has been firmly detected; c) two absorption features at about 0.7 and 1 keV are found, the first corresponding to a blend of O VI and O VII, the other to a combination of FeL and NeK edges. Compared to an earlier ASCA observation, when the source was 30% fainter, the values of both the relative amount of reflection and the warm absorber ionization degree are significantly lower: the comparison is suggestive of sizeable delay effects in this object, due to geometrical factors in the reflection, and to relaxation to equilibrium states in the ionization of the absorber. C1 Univ Roma Tre, Dipartimento Fis, I-00146 Rome, Italy. CNR, Ist Tecnol & Radiaz Extraterr, I-40129 Bologna, Italy. Osservatorio Astron Roma, I-00044 Monte Porzio Catone, Italy. European Space Agcy, Estec, Dept Space Sci, Div Astrophys, NL-2200 AG Noordwijk, Netherlands. CNR, Ist Fis Cosm & Applicaz Informat, I-90146 Palermo, Italy. CNR, Ist Fis Cosm G Occhialini, I-20133 Milan, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CNR, Ist Astrofis Spaziale, I-00133 Rome, Italy. Osservatorio Astron Bologna, I-40127 Bologna, Italy. RP Perola, GC (reprint author), Univ Roma Tre, Dipartimento Fis, Via Vasca Navale 84, I-00146 Rome, Italy. EM perola@fis.uniroma3.it RI PIRO, LUIGI/E-4954-2013; Cappi, Massimo/F-4813-2015; Stirpe, Giovanna/O-9393-2015; OI PIRO, LUIGI/0000-0003-4159-3984; Stirpe, Giovanna/0000-0002-3702-8731; Cappi, Massimo/0000-0001-6966-8920; Nicastro, Fabrizio/0000-0002-6896-1364; Mineo, Teresa/0000-0002-4931-8445; Molendi, Silvano/0000-0002-2483-278X; Fiore, Fabrizio/0000-0002-4031-4157 NR 37 TC 22 Z9 22 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 NOV PY 1999 VL 351 IS 3 BP 937 EP 944 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 262LG UT WOS:000084068300019 ER PT J AU Loinard, L Dame, TH Heyer, MH Lequeux, J Thaddeus, P AF Loinard, L Dame, TH Heyer, MH Lequeux, J Thaddeus, P TI A CO survey of the southwest half of M 31 SO ASTRONOMY & ASTROPHYSICS LA English DT Letter DE galaxies : ISM; galaxies : individual : M 31; galaxies : spiral; ISM : structure; ISM : molecules; ISM : clouds ID MASSIVE MOLECULAR CLOUDS; RESOLUTION IRAS MAPS; HYDROGEN-LINE SURVEY; INNER DISK; CARBON-MONOXIDE; SPIRAL ARM; INTERSTELLAR-MEDIUM; ANDROMEDA GALAXY; DENSITY-WAVE; M31 AB A CO survey of most of the southwest half of M 31 at an effective angular resolution of 1' has been performed with the 14-m radiotelescope of the Five College Radio Astronomy Observatory QUARRY receiver array. At the 200 pc linear resolution of this instrument at the distance of M 31 (690 kpc), the CO emission, already known to peak in a broad Population I ring 10 kpc in radius, is found to be concentrated in two spiral arm segments, Baade's (1963) S3 and S4, both well defined in space and velocity. Fainter CO emission features are also detected further from the center, mainly in the outer arm S5, and closer to the center. The prominent molecular arms S3 and S4 are aligned with dust and atomic counterparts. At the intersection of S4 with the major axis, there is an offset between the arm defined by gas and dust and that defined by the classical tracers of Population I objects. The H II regions are mostly concentrated along the outer edge of the gaseous arm, and the OB associations are found even further out. However, no significant streaming motions are detected across the arm. Although overall M 31 is several times fainter in CO than the Milky Way, the CO distributions in the two galaxies are similar in certain respects. The prominent molecular spiral arm S4 in hi 31 is very much like the Carina arm in our Galaxy at the same galactocentric radius, and beyond a radius of about 8 kpc (the solar circle), M 31 and the Milky Way are very similar in their molecular content. The overall difference in CO intensity between the two galaxies originates in the inner 7 kpc where M 31 is very dim and the Milky Way very bright. However, even in this inner region, common features are found. First, the ratio between the CO intensity and the H I column density changes in the same way with galactocentric radius in both systems, rising inwards to about 2-3 kpc from the center. Second, the molecular gas in the inner two kiloparsecs appears in both cases to follow a perturbed kinematics, perhaps as a result of a stellar bar. C1 Inst Radio Astron Millimetr, F-38406 St Martin Dheres, France. Observ Grenoble, Astrophys Lab, F-38041 Grenoble, France. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Massachusetts, Dept Phys & Astron, Amherst, MA 01003 USA. Univ Massachusetts, FCRAO, Amherst, MA 01003 USA. Observ Paris, DEMIRM, F-75014 Paris, France. RP Inst Radio Astron Millimetr, 300 Rue Piscine, F-38406 St Martin Dheres, France. EM loinard@iram.fr NR 66 TC 34 Z9 34 U1 1 U2 2 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 1432-0746 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD NOV PY 1999 VL 351 IS 3 BP 1087 EP 1102 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 262LG UT WOS:000084068300036 ER PT J AU Vikhlinin, A Forman, W Jones, C AF Vikhlinin, A Forman, W Jones, C TI Outer regions of the cluster gaseous atmospheres SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : clusters : general X-rays : galaxies ID X-RAY-CLUSTERS; N-BODY SIMULATIONS; COOLING FLOWS; TEMPERATURE RELATION; GALAXY FORMATION; EMITTING GAS; HOT PLASMA; ROSAT; MASS; EINSTEIN AB We present a systematic study of the hot gas distribution in the outer regions of regular clusters using ROSAT PSPC data. Outside the cooling how region, the beta-model describes the observed surface brightness closely, but not precisely. Between 0.3 and 1 virial radii, the profiles are characterized by a power law with slope, expressed in terms of the beta-parameter, in the range beta = 0.65-0.85. The values of beta in this range of radii are typically larger by approximate to 0.05 than those derived from the global fit. There is a mild trend for the slope to increase with temperature, from [beta] approximate to 0.68 for 3 keV clusters to approximate to 0.8 for 10 keV clusters; however, even at high temperatures there are clusters with flat gas profiles, beta < 0.7. Our values of beta at large radius are systematically higher, and the trend of beta with temperature is weaker than was previously found; the most likely explanation is that earlier studies were affected by an incomplete exclusion of the central cooling how regions. For our regular clusters, the gas distribution at large radii is quite close to spherically symmetric, and this is shown not to be an artifact of the sample selection. The gas density profiles are very similar when compared in units of the cluster virial radius. The radius of fixed mean gas overdensity 1000 (corresponding to the dark matter overdensity 200 for Omega = 0.2) shows a tight correlation with temperature, R similar to T-0.5, as expected from the virial theorem for clusters with the universal gas fraction. At a given temperature, the rms scatter of the gas overdensity radius is only approximate to 7%, which translates into a 20% scatter of the gas mass fraction, including statistical scatter due to measurement uncertainties. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Vikhlinin, A (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 45 TC 150 Z9 150 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 NOV 1 PY 1999 VL 525 IS 1 BP 47 EP 57 DI 10.1086/307876 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 251MR UT WOS:000083449900006 ER PT J AU Prosser, CF Kennicutt, RC Bresolin, F Saha, A Sakai, S Freedman, WL Mould, JR Ferrarese, L Ford, HC Gibson, BK Graham, JA Hoessel, JG Huchra, JP Hughes, SM Illingworth, GD Kelson, DD Macri, L Madore, BF Silbermann, NA Stetson, PB AF Prosser, CF Kennicutt, RC Bresolin, F Saha, A Sakai, S Freedman, WL Mould, JR Ferrarese, L Ford, HC Gibson, BK Graham, JA Hoessel, JG Huchra, JP Hughes, SM Illingworth, GD Kelson, DD Macri, L Madore, BF Silbermann, NA Stetson, PB TI The Hubble Space Telescope key project on the extragalactic distance scale. XXII. The discovery of Cepheids in NGC 1326A SO ASTROPHYSICAL JOURNAL LA English DT Article DE Cepheids; galaxies : distances and redshifts; galaxies : individual (NGC 1326A) ID FORNAX CLUSTER; PHOTOMETRY; GALAXIES; PERFORMANCE; CALIBRATION; EXTINCTION; WFPC2 AB We report on the detection of Cepheids and the first distance measurement to the spiral galaxy NGC 1326A, a member of the Fornax Cluster of galaxies. We have employed data obtained with the Wide Field and Planetary Camera 2 on board the Hubble Space Telescope. Over a 49 day interval, a total of 12 V-band (F555W) and eight I-band (F814W) epochs of observation were obtained. Two photometric reduction packages, ALLFRAME and DoPHOT, have been employed to obtain photometry measures from the three Wide Field CCDs. Variability analysis yields a total of 17 Cepheids in common with both photometry data sets, with periods ranging between 10 and 50 days. Of these, 14 Cepheids with high-quality light curves are used to fit the V and I period-luminosity relations and derive apparent distance moduli, assuming a Large Magellanic Cloud distance modulus mu(LMC) = 18.50 +/- 0.10 mag and color excess E(B-V) = 0.10 mag. Assuming A(V)/E(V-I) = 2.45, the DoPHOT data yield a true distance modulus to NGC 1326A of mu(0) = 31.36 +/- 0.17(random) +/- 0.13(systematic) mag, corresponding to a distance of 18.7 +/- 1.5(random) +/- 1.2(systematic) Mpc. The derived distance to NGC 1326A is in good agreement with the distance derived previously to NGC 1365, another spiral galaxy member of the Fornax Cluster. However, the distances to both galaxies are significantly lower than that to NGC 1425, a third Cepheid calibrator in the outer parts of the cluster. C1 Natl Opt Astron Observ, Tucson, AZ 85726 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. European So Observ, D-8046 Garching, Germany. Carnegie Inst Washington Observ, Pasadena, CA 91101 USA. Australian Natl Univ, Mt Stromlo & Siding Spring Observ, Res Sch Astron & Astrophys, Weston, ACT 2611, Australia. CALTECH, Dept Astron, Pasadena, CA 91125 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Univ Colorado, Ctr Astrophys & Space Astron, Boulder, CO 80309 USA. Carnegie Inst Washington, Dept Terr Magnetism, Washington, DC 20015 USA. Univ Wisconsin, Dept Astron, Madison, WI 53706 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. Univ Calif Santa Cruz, Lick Observ, Santa Cruz, CA 95064 USA. CALTECH, Pasadena, CA 91125 USA. NASA IPAC Extragalact Database, Pasadena, CA 91125 USA. CALTECH, IPAC, Pasadena, CA 91125 USA. Natl Res Council Canada, Herzberg Inst Astrophys, Dominion Astrophys Observ, Victoria, BC V8X 4M6, Canada. RI Gibson, Brad/M-3592-2015 OI Gibson, Brad/0000-0003-4446-3130 NR 37 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 NOV 1 PY 1999 VL 525 IS 1 BP 80 EP 104 DI 10.1086/307899 PN 1 PG 25 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 251MR UT WOS:000083449900008 ER PT J AU Slane, P Gaensler, BM Dame, TM Hughes, JP Plucinsky, PP Green, A AF Slane, P Gaensler, BM Dame, TM Hughes, JP Plucinsky, PP Green, A TI Nonthermal X-ray emission from the shell-type supernova remnant G347.3-0.5 SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : individual (G347.3-0.5); supernova remnants; X-rays : ISM ID MILKY-WAY; CO SURVEY; SN-1006; MODEL; ACCELERATION; ELECTRONS; BUBBLES; CLOUDS; GALAXY; WIND AB Recent ASCA observations of G347.3-0.5, a supernova remnant (SNR) discovered in the ROSAT All-Sky Survey, reveal nonthermal emission from a region along the northwestern shell. Here we report on new pointed ASCA observations of G347.3-0.5 that confirm this result for all the bright shell regions and also reveal similar emission, although with slightly different spectral properties, from the remainder of the SNR. Curiously, no thermal X-ray emission is detected anywhere in the remnant. We derive limits on the amount of thermal emitting material present in G347.3-0.5 and present new radio continuum, CO, and infrared results that indicate that the remnant is distant and of moderate age. We show that our observations are broadly consistent with a scenario that has most of the supernova remnant shock wave still within the stellar wind bubble of its progenitor star, while part of it appears to be interacting with denser material. A point source at the center of the remnant has spectral properties similar to those expected for a neutron star and may represent the compact relic of the supernova progenitor. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. MIT, Ctr Space Res, Cambridge, MA 02139 USA. Univ Sydney, Sch Phys, Dept Astrophys, Sydney, NSW 2006, Australia. CSIRO, Australia Telescope Natl Facil, Epping, NSW 1710, Australia. Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08854 USA. RP Slane, P (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Gaensler, Bryan/F-8655-2010; OI Gaensler, Bryan/0000-0002-3382-9558 NR 45 TC 197 Z9 199 U1 3 U2 3 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 NOV 1 PY 1999 VL 525 IS 1 BP 357 EP 367 DI 10.1086/307893 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 251MR UT WOS:000083449900028 ER PT J AU Luhman, KL Rieke, GH AF Luhman, KL Rieke, GH TI Low-mass star formation and the initial mass function in the rho Ophiuchi cloud core SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : stars; open clusters and associations : individual (rho Ophiuchi); stars : evolution; stars : low-mass, brown dwarfs; stars : luminosity function, mass function; stars : pre-main-sequence ID YOUNG STELLAR OBJECTS; NEAR-INFRARED SPECTRA; MAIN-SEQUENCE STARS; X-RAY SOURCES; DARK-CLOUD; BROWN DWARFS; EVOLUTIONARY STATUS; IRAS OBSERVATIONS; STANDARD STARS; EXTINCTION LAW AB We have obtained moderate-resolution (R = 800-1200) K-band spectra for similar to 100 stars within and surrounding the cloud core of rho Oph. We have measured spectral types and continuum veilings and have combined this information with results from new deep imaging. Using the latest evolutionary tracks of D'Antona & Mazzitelli to interpret the M-R diagram for rho Oph, we infer ages ranging between 0.1 and 1 Myr for the class II and III sources (i.e., those that have emerged from their natal cocoons). A few stars may be slightly older. The initial mass function (IMF) peaks at about 0.4 M. and slowly declines to the hydrogen-burning limit with a slope of similar to-0.5 in logarithmic units (Salpeter is +1.35). Our lower limits on the numbers of substellar objects demonstrate that the IMF probably does not fall more steeply below the hydrogen-burning limit, at least down to similar to 0.02 M.. The derived IMF is consistent with previous findings that the rho Oph IMF is roughly flat from 0.05 tol M.. The exact shape of the mass function remains a function of the theoretical evolutionary tracks and, at the lowest masses, the conversion from spectral types to effective temperatures. We then make the first comparison of mass functions of stars and prestellar clumps measured in the same region. The similar behavior of the two mass functions in rho Oph supports the suggestion of Motte et al. and Testi & Sargent that the stellar mass function in young clusters is a direct product of the process of cloud fragmentation. We have also studied the very young and often still embedded class I and hat-spectrum objects. After considering the effect of extinction on the SED classifications of the sample, we find that similar to 17% of the rho Oph stars are class I, implying similar to 0.1 Myr for the lifetime of this stage. In spectra separated by 2 yr, we observe simultaneous variability in the Br gamma emission and K-band continuum veiling for two stars, where the hydrogen emission is brighter in the more heavily veiled data. This behavior indicates that the disk may contribute significantly to continuous K-band emission, in contrast to the proposal that the infalling envelope always dominates. Our detection of strong 2 mu m veiling (r(K) =1-4) in several class II and III stars, which should have disks but little envelope material, further supports this proposition. We also detect absorption features in the spectra of similar to 25% of class I and Bat-spectrum sources, demonstrating the feasibility of studying the photospheres of extremely young protostars. C1 Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. RP Luhman, KL (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 87 TC 217 Z9 217 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 NOV 1 PY 1999 VL 525 IS 1 BP 440 EP 465 DI 10.1086/307891 PN 1 PG 26 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 251MR UT WOS:000083449900036 ER PT J AU Luhman, KL AF Luhman, KL TI Young low-mass stars and brown dwarfs in IC 348 SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : stars; stars : evolution; stars : formation; stars : low-mass, brown dwarfs; stars : luminosity function, mass function; stars : pre-main-sequence ID DENIS-P J1228.2-1547; SPECTRAL SEQUENCE; TEMPERATURE SCALE; PHOTOMETRY; CLUSTERS; IC-348; TAURI; DISCOVERY; MICRONS; MODELS AB I present new results from a continuing program to identify and characterize the low-mass stellar and substellar populations in the young cluster IC 348 (0.5-10 Myr). Optical spectroscopy has revealed young objects with spectral types as late as M8.25. The intrinsic J-H and H-K colors of these sources are dwarflike, whereas the R-I and I-J colors appear intermediate between the colors of dwarfs and giants. Furthermore, the spectra from 6500 to 9500 Angstrom are reproduced well with averages of standard dwarf and giant spectra, suggesting that such averages should be used in the classification of young late-type sources. An H-R diagram is constructed for the low-mass population in IC 348 (K6-M8). The presumably coeval components of the young quadruple system GG Tau (White et al.) and the locus of stars in IC 348 are used as empirical isochrones to test the theoretical evolutionary models. The calculations of Burrows et al. do not appear to be consistent with the data at these earliest stages of stellar evolution. There is fair agreement between the data and the model isochrones of D'Antona & Mazzitelli, except near the hydrogen-burning limit. The agreement cannot be improved by changing the conversion between spectral types and effective temperatures, On the other hand, for the models of Baraffe et al., an adjustment of the temperature scale to progressively warmer temperatures at later RI types, intermediate between dwarfs and giants, brings all components of GG Tau onto the same model isochrone and gives the population of IC 348 a constant age and age spread as a function of mass. When other observational constraints are considered, such as the dynamical masses of GM Bur, DM Tau, and GG Tau-A, the models of Baraffe et al, are the most consistent with observations of young systems. With compatible temperature scales, the models of both D'Antona & Mazzitelli and Baraffe et al. suggest that the hydrogen-burning mass limit occurs near M6 at ages of less than or similar to 10 Myr. Thus, several likely brown dwarfs are discovered in this study of IC 348, with masses down to similar to 20-30 M-J. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Luhman, KL (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 64 TC 284 Z9 284 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 NOV 1 PY 1999 VL 525 IS 1 BP 466 EP 481 DI 10.1086/307902 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 251MR UT WOS:000083449900037 ER PT J AU Jha, S Garnavich, PM Kirshner, RP Challis, P Soderberg, AM Macri, LM Huchra, JP Barmby, P Barton, EJ Berlind, P Brown, WR Caldwell, N Calkins, ML Kannappan, SJ Koranyi, DM Pahre, MA Rines, KJ Stanek, KZ Stefanik, RP Szentgyorgyi, AH Vaisanen, P Wang, Z Zajac, JM Riess, AG Filippenko, AV Li, WD Modjaz, M Treffers, RR Hergenrother, CW Grebel, EK Seitzer, P Jacoby, GH Benson, PJ Rizvi, A Marschall, LA Goldader, JD Beasley, M Vacca, WD Leibundgut, B Spyromilio, J Schmidt, BP Wood, PR AF Jha, S Garnavich, PM Kirshner, RP Challis, P Soderberg, AM Macri, LM Huchra, JP Barmby, P Barton, EJ Berlind, P Brown, WR Caldwell, N Calkins, ML Kannappan, SJ Koranyi, DM Pahre, MA Rines, KJ Stanek, KZ Stefanik, RP Szentgyorgyi, AH Vaisanen, P Wang, Z Zajac, JM Riess, AG Filippenko, AV Li, WD Modjaz, M Treffers, RR Hergenrother, CW Grebel, EK Seitzer, P Jacoby, GH Benson, PJ Rizvi, A Marschall, LA Goldader, JD Beasley, M Vacca, WD Leibundgut, B Spyromilio, J Schmidt, BP Wood, PR TI The Type Ia supernova 1998bu in M96 and the Hubble constant SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Review DE distance scale; galaxies : individual (M96); galaxies : photometry; supernovae : individual (SN 1998bu) ID CEPHEID DISTANCE SCALE; LIGHT-CURVE SHAPES; SPACE-TELESCOPE OBSERVATIONS; PERIOD-LUMINOSITY RELATION; INFRARED STANDARD STARS; LARGE-MAGELLANIC-CLOUD; RED CLUMP STARS; METALLICITY DEPENDENCE; HIPPARCOS PARALLAXES; PEAK BRIGHTNESS AB We present optical and near-infrared photometry and spectroscopy of the Type Ia SN 1998bu in the Leo I Group galaxy M96 (NGC 3368). The data set consists of 356 photometric measurements and 29 spectra of SN 1998bu between UT 1998 May 11 and July 15. The well-sampled light curve indicates the supernova reached maximum light in B on UT 1998 May 19.3 (JD 2450952.8+/-0.8) with B = 12.22 +/- 0.03 and V = 11.88 +/- 0.02. Application of a revised version of the Multicolor Light Curve Shape (MLCS) method yields an extinction toward the supernova of A(V) = 0.94 +/- 0.15 mag, and indicates the supernova was of average luminosity compared to other normal Type Ia supernovae. Using the HST Cepheid distance modulus to M96 and the MLCS fitted parameters for the supernova, we derive an extinction-corrected absolute magnitude for SN 1998bu at maximum, M(V) = -19.42 +/- 0.22. Our independent results for this supernova are consistent with those of Suntzeff et al. Combining SN 1998bu with three other well-observed local calibrators and 42 supernovae in the Hubble flow yields a Hubble constant, H(0) = 64(-6)(+8) km s(-1) Mpc(-1), where the error estimate incorporates possible sources of systematic uncertainty including the calibration of the Cepheid period-luminosity relation, the metallicity dependence of the Cepheid distance scale, and the distance to the LMC. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Univ Michigan, Dept Astron, Ann Arbor, MI 48109 USA. Kitt Peak Natl Observ, Natl Opt Astron Observ, Tucson, AZ 85726 USA. Wellesley Coll, Whitin Observ, Wellesley, MA 02181 USA. Gettysburg Coll, Dept Phys, Gettysburg, PA 17325 USA. Univ Penn, Dept Phys & Astron, Philadelphia, PA 19104 USA. Univ Colorado, Dept Astrophys & Planetary Sci, Boulder, CO 80309 USA. Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. European So Observ, Garching, Germany. Australian Natl Univ, Res Sch Astron & Astrophys, Canberra, ACT, Australia. Univ Calif Santa Cruz, Lick Observ, UCO, Santa Cruz, CA 95064 USA. RP Jha, S (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Barmby, Pauline/I-7194-2016; OI Barmby, Pauline/0000-0003-2767-0090; Schmidt, Brian/0000-0001-6589-1287; Macri, Lucas/0000-0002-1775-4859 NR 161 TC 148 Z9 149 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD NOV PY 1999 VL 125 IS 1 BP 73 EP 97 DI 10.1086/313275 PG 25 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 264BZ UT WOS:000084161300003 ER PT J AU Jijina, J Myers, PC Adams, FC AF Jijina, J Myers, PC Adams, FC TI Dense cores mapped in ammonia: A database SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Review DE ISM : clouds; ISM : molecules; radio lines : ISM; stars : pre-main-sequence ID MOLECULAR CLOUD CORES; YOUNG STELLAR OBJECTS; STAR-FORMING REGION; INITIAL MASS FUNCTION; NEAR-INFRARED IMAGES; MAGNETOCENTRIFUGALLY DRIVEN FLOWS; RADIO-CONTINUUM EMISSION; CEPHEUS OB3 ASSOCIATION; HERBIG-HARO OBJECTS; RHO-OPHIUCHI CLOUD AB We present a database of 264 cores mapped in the (J, K) = (1, 1) and (2, 2) lines of NH,. We list the core gas properties-peak positions, total ammonia column densities, intrinsic line widths, kinetic temperatures, volume densities, core sizes, aspect ratios, and velocity gradients, as well as the properties of associated young stellar objects (YSOs)-associated IRAS sources along with their luminosities and core-YSO distances, outflow velocities, and SIMBAD and cluster associations. We also present the results of our statistical analysis and enumerate important pairwise correlations among the various gas and YSO properties. The results indicate that the association of stellar clusters with star-forming cores has a greater impact on their properties than does the presence of associated YSOs within these cores, although the latter influence is also statistically significant. In other words, the difference in core properties (nonthermal line widths, kinetic temperatures, and core sizes) between cores with and without associated YSOs is less significant when compared with the difference in these properties between cores with and without cluster associations. Furthermore, core gas and YSO properties show a significant dependence on the star-forming region in which the core is located. For instance, cores in Orion have larger line widths, higher kinetic temperatures, and larger sizes compared with cores in Taurus. Similarly, YSOs in Orion are more luminous than those in Taurus. These cluster and regional dependencies seem important enough that they ought to be accounted for in any self-consistent theory of star formation. Finally, the ratio of starless to stellar cores is too small (8:12 in Taurus, 2:41 in Orion A) to be consistent with ambipolar diffusion timescales that predict ratios as high as 3-30. This result is true even for regions that are known to be well. surveyed and not to suffer from significant sample biases. C1 Univ Michigan, Dept Phys, Randall Labs, Ann Arbor, MI 48109 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Jijina, J (reprint author), Univ Michigan, Dept Phys, Randall Labs, Ann Arbor, MI 48109 USA. EM jjijina@umich.edu; pmyers@cfa.harvard.edu; adams@pablo.physics.lsa.umich.edu NR 291 TC 297 Z9 299 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD NOV PY 1999 VL 125 IS 1 BP 161 EP 236 DI 10.1086/313268 PG 76 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 264BZ UT WOS:000084161300007 ER PT J AU Dalgarno, A Yan, M Liu, WH AF Dalgarno, A Yan, M Liu, WH TI Electron energy deposition in a gas mixture of atomic and molecular hydrogen and helium SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE atomic processes; ISM : abundances; ISM : molecules; X-rays : general ID SPONTANEOUS RADIATIVE DISSOCIATION; TOTAL CROSS-SECTIONS; N = 4; INTERSTELLAR-MOLECULES; COLLISION STRENGTHS; IMPACT EXCITATION; CHARGED PARTICLES; THERMAL-ELECTRONS; BINARY-MIXTURES; INITIAL YIELDS AB A detailed discussion is presented of the slowing down of fast electrons in a partly ionized gas mixture of H, H-2 and He with a varying ratio of H to H, and a fixed fraction of He. The mean energies and yields for ionization, electronic excitation, dissociation, and vibrational excitation and the heating efficiencies are calculated for fractional ionizations from 0 to 0.1. Analytical formulas are obtained for many of the parameters. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Dalgarno, A (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 82 TC 123 Z9 123 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD NOV PY 1999 VL 125 IS 1 BP 237 EP 256 DI 10.1086/313267 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 264BZ UT WOS:000084161300008 ER PT J AU Brown, JL Schmitt, DL Bellem, A Graham, LH Lehnhardt, J AF Brown, JL Schmitt, DL Bellem, A Graham, LH Lehnhardt, J TI Hormone secretion in the Asian elephant (Elephas maximus): Characterization of ovulatory and anovulatory luteinizing hormone surges SO BIOLOGY OF REPRODUCTION LA English DT Article ID LOXODONTA-AFRICANA ELEPHANTS; PROGESTERONE SECRETION; SERUM PROGESTERONE; OVARIAN-FUNCTION; ESTROUS-CYCLE; REPRODUCTION; PROLACTIN; CAPTIVITY; PREGNANCY; PATTERNS AB In the elephant, two distinct LH surges occur 3 wk apart during the nonluteal phase of the estrous cycle, but only the second surge (ovLH) induces ovulation. The function of the first, anovulatory surge (anLH) is unknown, nor is it clear what regulates the timing of these two surges. To further study this observation in the Asian elephant, serum concentrations of LH, FSH, progesterone, inhibin, estradiol, and prolactin were quantified throughout the estrous cycle to establish temporal hormonal relationships. To examine long-term dynamics of hormone secretion, analyses were conducted in weekly blood samples collected from 3 Asian elephants for up to 3 yr. To determine whether differences existed in secretory patterns between the anLH and ovLH surges, daily blood samples were analyzed from 21 nonluteal-phase periods from 7 Asian elephants. During the nonluteal phase, serum LH was elevated for 1-2 days during anLH and ovLH surges with no differences in peak concentration between the two surges. The anLH surge occurred 19.9 +/- 1.2 days after the end of the luteal phase and was followed by the ovLH surge 20.8 +/- 0.5 days later. Serum FSH concentrations were highest at the beginning of the nonluteal phase and gradually declined to nadir concentrations within 4 days of the ovLH surge. FSH remained low until after the ovLH surge and then increased during the luteal phase. Serum inhibin concentrations were negatively correlated with FSH during the nonluteal phase (r = -0.53). Concentrations of estradiol and prolactin fluctuated throughout the estrous cycle with no discernible patterns evident. In sum, there were no clear differences in associated hormone secretory patterns between the anLH and ovLH surge. However, elevated FSH at the beginning of the nonluteal phase may be important for follicle recruitment, with the first anLH surge acting to complete the follicle selection process before ovulation. C1 Conservat & Res Ctr, Smithsonian Inst, Front Royal, VA 22630 USA. Dickerson Pk Zoo, Springfield, MO 65803 USA. SW Missouri State Univ, Dept Agr, Springfield, MO 65804 USA. RP Brown, JL (reprint author), Conservat & Res Ctr, Smithsonian Inst, 1500 Remount Rd,Natl Zool Pk, Front Royal, VA 22630 USA. NR 31 TC 67 Z9 69 U1 1 U2 10 PU SOC STUDY REPRODUCTION PI MADISON PA 1603 MONROE ST, MADISON, WI 53711-2021 USA SN 0006-3363 J9 BIOL REPROD JI Biol. Reprod. PD NOV PY 1999 VL 61 IS 5 BP 1294 EP 1299 DI 10.1095/biolreprod61.5.1294 PG 6 WC Reproductive Biology SC Reproductive Biology GA 248WY UT WOS:000083300800016 PM 10529277 ER PT J AU Rappole, JH King, DI Barrow, WC AF Rappole, JH King, DI Barrow, WC TI Winter ecology of the endangered Golden-cheeked Warbler SO CONDOR LA English DT Article DE Dendroica chrysoparia; endangered species; foraging behavior; habitat-use; Neotropical migrant; winter ecology ID HABITAT; SEGREGATION; MEXICO AB We studied the ecology of the Golden-cheeked Warbler (Dendroica chrysoparia) during three winter seasons, 1995-1998, in Honduras, Guatemala, and Mexico. Individuals of this species occurred almost exclusively as members of mixed-species Becks, occupying sites with greater densities of encino oak and ground cover and fewer pines than random sites. Most foraging observations were recorded in mid-story, encino oak. Commonly-observed foraging maneuvers were gleaning and sally-hovering. Eighty-three percent of foraging maneuvers were directed at the outermost portions of the oak foliage. Flocks in which Golden-cheeked Warblers occurred contained an average of 20.5 individuals and 12.9 species other than Golden-cheeked Warblers. The most frequently co-occurring species were Wilson's Warbler (Wilsonia pusilla), Black-throated Green Warbler (Dendroica virens), Hermit Warbler (D. occidentalis), Townsend's Warbler (D. townsendi), and Blue-headed Vireo (Vireo solitarius). The ratio of males to females observed was not substantially different from 1:1, and there was little evidence of sexual differences in habitat use. Golden-cheeked Warblers appeared to be tolerant of moderate levels of logging and grazing, but understory clearing to promote grazing for cattle may pose a significant threat to winter habitat availability. C1 Smithsonian Conservat & Res Ctr, Front Royal, VA 22630 USA. Univ Massachusetts, Dept Forestry & Wildlife Management, Holdsworth Nat Resources Ctr 203, Amherst, MA 01003 USA. Natl Wetlands Res Ctr, Lafayette, LA 70506 USA. RP Rappole, JH (reprint author), Smithsonian Conservat & Res Ctr, 1500 Remount Rd, Front Royal, VA 22630 USA. NR 32 TC 10 Z9 10 U1 0 U2 10 PU COOPER ORNITHOLOGICAL SOC PI LAWRENCE PA ORNITHOLOGICAL SOC NORTH AMER PO BOX 1897, LAWRENCE, KS 66044-8897 USA SN 0010-5422 J9 CONDOR JI Condor PD NOV PY 1999 VL 101 IS 4 BP 762 EP 770 DI 10.2307/1370063 PG 9 WC Ornithology SC Zoology GA 259FP UT WOS:000083884100005 ER PT J AU Milne, GA Mitrovica, JX Davis, JL AF Milne, GA Mitrovica, JX Davis, JL TI Near-field hydro-isostasy: the implementation of a revised sea-level equation SO GEOPHYSICAL JOURNAL INTERNATIONAL LA English DT Article DE crustal deformation; glacial rebound; sea level ID COMPUTING 3-DIMENSIONAL DEFORMATIONS; MANTLE VISCOSITY; SPECTRAL FORMALISM; LATE PLEISTOCENE; HIGH-RESOLUTION; ROTATING EARTH; SURFACE LOADS; HUDSON-BAY; ADJUSTMENT; ICE AB We describe how the existing sea-level equation incorrectly predicts the change in sea level (and thus the ocean load) in ice-covered, subgeoidal geographic regions during periods of deglaciation. We go on to present a new sea-level equation that overcomes this problem and we describe how this equation can be solved in a gravitationally self-consistent manner by employing a well-known spectral technique, application of the new theory to predict relative sea-level (rsl) histories and present-day, 3-D, solid surface deformation rates in northeastern Canada (based on a single earth model characterized by a lithospheric thickness of 100 km and upper and lower mantle viscosities of 5 x 10(20) and 5 x 10(21) Pa s, respectively) demonstrates that a significant error is introduced when the original theory is employed to predict the oceanic component of the surface load. Predictions of rsl curves show a discrepancy of similar to 40 per cent at sites where data have been obtained and employed to constrain models of earth viscosity structure and ice-sheet histories. This error will significantly bias estimates of mantle viscosity structure and ice thicknesses that are based on the original theory, In addition, predictions of 3-D deformation rates differ by up to 25 per cent in some regions and so future applications that employ these data to constrain models of the glacial isostatic adjustment process should adopt the improved sea-level theory. In contrast, estimates of inverse decay times from the predicted rsl curves are insensitive (to within the observational error) to the improvement in the surface load introduced by the new theory. Thus, viscosity structure inferences based on this parametrization and the original sea-level equation are unaffected by the error in the ocean load. Finally, the new theory predicts a eustatic (i.e. globally uniform) rise in sea level over the postglacial period that is similar to 11 m lower than that determined via the original theory, Therefore, estimates of the global ice budget at the last glacial maximum based on far-field rsl data and the original sea-level theory will be too small by similar to 10 per cent. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Toronto, Dept Phys, Toronto, ON M5S 1A7, Canada. RP Milne, GA (reprint author), Univ Durham, Dept Geol Sci, Sci Labs, South Rd, Durham DH1 3LE, England. RI Davis, James/D-8766-2013 OI Davis, James/0000-0003-3057-477X NR 38 TC 86 Z9 87 U1 0 U2 1 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0956-540X J9 GEOPHYS J INT JI Geophys. J. Int. PD NOV PY 1999 VL 139 IS 2 BP 464 EP 482 DI 10.1046/j.1365-246x.1999.00971.x PG 19 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 253CJ UT WOS:000083538800015 ER PT J AU Jakab, PL AF Jakab, PL TI Wood to metal: The structural origins of the modern airplane SO JOURNAL OF AIRCRAFT LA English DT Article AB The transition from the wood-and-fabric airplane to the ah-metal airplane was essentially complete by World War II. The late 1920s and early 1930s are said to have witnessed a structural revolution in aeronautics with the appearance of streamlined metal aircraft with such features as tightly cowled multiple engines, variable-pitch propellers, retracting landing gear, and stressed-skin aluminum construction. A prevalent assumption regarding this transition is that the building material acted as a primary driver of change, that engineering advance was guided by an inevitable move toward metal structures. Metal did indeed allow engineers to extend performance parameters afforded by innovative structural designs, but, interestingly, many of these key innovations were not developed to take advantage of metal. They emerged independent of the the construction material, and often were first used in wooden airplanes. The cluster of original ideas that coalesced in the 1930s constituted one of the major watershed periods in aerospace technology. Metal carried this basic design revolution to the limits of its engineering and technical feasibility, but only after a new foundation was in place. Metal did not spawn the structural revolution. An exploration of the roots of the structural revolution in aeronautics and the complexity of technological progress is presented. C1 Smithsonian Inst, Natl Air & Space Museum, Aeronaut Div, Washington, DC 20560 USA. RP Jakab, PL (reprint author), Smithsonian Inst, Natl Air & Space Museum, Aeronaut Div, Rm 3322,MRC 312, Washington, DC 20560 USA. NR 12 TC 4 Z9 4 U1 0 U2 4 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD NOV-DEC PY 1999 VL 36 IS 6 BP 914 EP 918 DI 10.2514/2.2551 PG 5 WC Engineering, Aerospace SC Engineering GA 264NF UT WOS:000084187800003 ER PT J AU Ricklefs, RE Lovette, IJ AF Ricklefs, RE Lovette, IJ TI The roles of island area per se and habitat diversity in the species-area relationships of four Lesser Antillean faunal groups SO JOURNAL OF ANIMAL ECOLOGY LA English DT Review DE area effects; habitat diversity; island biogeography; Lesser Antilles; species-area relationship ID WESTERN AUSTRALIAN WHEATBELT; ANOLIS LIZARDS; LAND BIRDS; RAIN-FOREST; RICHNESS; POPULATION; EXTINCTION; SIZE; HETEROGENEITY; BIOGEOGRAPHY AB 1. We analysed the relationships between species richness, island area, and habitat diversity for birds, bats, butterflies, and reptiles and amphibians on 19 islands in the Lesser Antilles. Habitat diversity was quantified by Simpson's index based on the total areas of five vegetation types on each island. Island area varied over two orders of magnitude (13-1510 km(2)) and habitat diversity varied between 1 and 3.7 equivalents of equally abundant habitat types. 2. Because the Lesser Antilles consist of an inner are of high, volcanic islands and an outer are of low-lying islands formed of uplifted marine sediments, correlations between area and elevation (r(2) = 0.32) and between area and habitat diversity (r(2) = 0.40) were weak. Habitat diversity was, however, strongly correlated with maximum island elevation (r(2) = 0.85). 3. Simple correlations of species richness with island area were significant for all four faunal groups, and simple correlations of species richness with elevation and habitat were significant for all groups except bats. In multiple regressions of species richness on area and habitat diversity together, area was a significant effect for birds and bats, and habitat diversity was a significant effect for birds, butterflies, and reptiles and amphibians. 4. These results suggest that the four Lesser Antillean taxonomic groups differ in their responses to area and habitat diversity. For butterflies and for reptiles and amphibians, the relationship of species richness to area is probably a fortuitous consequence of a relationship between habitat diversity and area. Bird species richness responds independently to both habitat diversity and area, and bat species richness is influenced by area but not by habitat diversity. 5. We suggest that this variation is related to differences in several biological traits of the different faunal groups. Strong habitat-diversity effects are likely in taxa with high degrees of habitat specialization, populations large enough to have a low probability of stochastic extinction, life-cycles that include a resistant resting stage that reduces vulnerability to catastrophic extinction, or a combination of these traits. In contrast, strong: area effects are likely in taxa with weak habitat specialization, low population density, or both. 6. At least in Lesser Antillean birds, it is unlikely that immigration depends on island size. Therefore, the species-area relationship for birds is probably generated by island-size-dependent extinction. Among the four taxonomic groups we studied, only butterflies are likely to show a 'rescue effect' stemming from frequent between-island movement of individuals, as only butterflies exhibited low levels of endemism and lacked a unique area effect for species richness. 7. Considered in concert, these taxon-specific differences demonstrate that both biological characteristics of organisms and geographical features of island groups mediate the relative contribution of island area and habitat diversity to variation in species richness. C1 Univ Missouri, Dept Biol, St Louis, MO 63121 USA. Univ Penn, Dept Biol, Philadelphia, PA 19104 USA. Smithsonian Trop Res Inst, Miami, FL 34002 USA. RP Univ Missouri, Dept Biol, 8001 Nat Bridge Rd, St Louis, MO 63121 USA. EM ricklefs@jinx.umsl.edu RI Lovette, Irby/P-3477-2014 NR 121 TC 251 Z9 262 U1 7 U2 98 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0021-8790 EI 1365-2656 J9 J ANIM ECOL JI J. Anim. Ecol. PD NOV PY 1999 VL 68 IS 6 BP 1142 EP 1160 DI 10.1046/j.1365-2656.1999.00358.x PG 19 WC Ecology; Zoology SC Environmental Sciences & Ecology; Zoology GA 265BJ UT WOS:000084218700007 ER PT J AU Odo, F AF Odo, F TI Storied lives: Japanese-American students and World War II. SO JOURNAL OF ASIAN STUDIES LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Odo, F (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ASSN ASIAN STUDIES INC PI ANN ARBOR PA UNIV MICH 1 LANE HALL, ANN ARBOR, MI 48109 USA SN 0021-9118 J9 J ASIAN STUD JI J. Asian Stud. PD NOV PY 1999 VL 58 IS 4 BP 1147 EP 1149 DI 10.2307/2658540 PG 3 WC Area Studies; Asian Studies SC Area Studies; Asian Studies GA 291EW UT WOS:000085722000050 ER PT J AU Correll, DL Jordan, TE Weller, DE AF Correll, DL Jordan, TE Weller, DE TI Precipitation effects on sediment and associated nutrient discharges from Rhode River watersheds SO JOURNAL OF ENVIRONMENTAL QUALITY LA English DT Article ID PARTICULATE MATTER; STREAM ECOSYSTEM; PASTURE PROGRAM; PHOSPHORUS; NITROGEN; RUNOFF; EXPORT; FOREST; QUALITY; CARBON AB Total suspended sediment (TSS) concentrations and their nutrient composition were studied in discharges from seven contiguous small watersheds on the Atlantic Coastal Plain in Maryland for up to 22 yr. All watersheds were equipped with V-notch weirs and volume-integrating, now-proportional samplers. Spot samples were also taken for analysis of TSS concentrations and the composition of dissolved and particulate nutrients at knows water discharge rates. Interannual variations in annual and seasonal precipitation during this study spanned approximately the range of 160-yr weather records in the vicinity. Mean annual TSS fluxes were 263, 546, 134, and 92 kg ha(-1) for the area-weighted mean of the overall Rhode River watershed, and for subwatersheds that were primarily-cropland, completely forested, and grazed, respectively. TSS fluxes were highest in the summer, followed by spring, winter, and fall. Regressions of TSS flux vs precipitation were used to calculate TSS fluxes for seasons and years with average, above and below the average precipitation. TSS flux from the Rhode River watershed was 12-fold higher in very wet years than in very dry years and 271-fold higher in very wet summers than in very dry summers. At base flow, TSS had high nutrient content, but as flow rates increased TSS nutrient content rapidly declined. At base flow, most of the total-P, TPi, TKN, and organic-C was in the dissolved phase, while at higher flows, most of these nutrients were in the TSS phase. C1 Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. RP Correll, DL (reprint author), Smithsonian Environm Res Ctr, POB 28, Edgewater, MD 21037 USA. OI Weller, Donald/0000-0002-7629-5437 NR 41 TC 17 Z9 17 U1 0 U2 0 PU AMER SOC AGRONOMY PI MADISON PA 677 S SEGOE RD, MADISON, WI 53711 USA SN 0047-2425 J9 J ENVIRON QUAL JI J. Environ. Qual. PD NOV-DEC PY 1999 VL 28 IS 6 BP 1897 EP 1907 PG 11 WC Environmental Sciences SC Environmental Sciences & Ecology GA 266EU UT WOS:000084288300029 ER PT J AU Hu, YQ Habbal, SR Li, X AF Hu, YQ Habbal, SR Li, X TI On the cascade processes of Alfven waves in the fast solar wind SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID MAGNETOHYDRODYNAMIC TURBULENCE; RADIAL EVOLUTION; POWER SPECTRUM; OBSERVATIONAL CONSTRAINTS; MHD TURBULENCE; ACCELERATION; FLUCTUATIONS; CORONA; MODEL; TEMPERATURE AB We present a numerical study which explores the nonlinear cascade effect associated with Alfven waves in the fast solar wind. The set of one-dimensional, two-fluid equations describing the solar wind and a power spectrum equation for Alfven waves, as first proposed by Tu et al. [1984], are solved simultaneously in a self-consistent manner. Both Kolmogorov and Kraichnan cascade functions, which vary as f(5/2)P(3/2) and f(3)P(2), respectively, are considered, For an Alfven wave spectrum at the coronal base, which is flat in the low-frequency range and has aslope of -1 in the high-frequency range, the Kolmogorov cascade function reproduces the Alfven wave spectrum observed beyond 0.29 AU very well. The Kraichnan cascade function, on the other hand, yields a spectrum that is within the 90% confidence level of the observed values. Both cascade functions yield a gradually accelerating fast solar wind in the inner corona, typical of wave acceleration models. The results of this first solar wind model which describes, in a self-consistent manner, the evolution of the wave spectrum and cascade in the inner corona confirm conclusions reached by earlier studies; namely, that the Kolmogorov process produces a stronger cascade effect than the Kraichnan process and seems more relevant for Alfven waves in the fast solar wind, at least beyond 0.29 AU. The approach shows that Alfven waves, with periods of hours or shorter, undergo an appreciable evolution from the solar surface to 1 AU, thus implying that their spectrum; hence their total energy flux at the Sun cannot be readily predicted from that observed in interplanetary space. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Sci & Technol China, Dept Earth & Space Sci, Hefei 230026, Peoples R China. RP Hu, YQ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 53 TC 49 Z9 49 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 NOV 1 PY 1999 VL 104 IS A11 BP 24819 EP 24834 DI 10.1029/1999JA900340 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 250XC UT WOS:000083414700019 ER PT J AU Sikes, NE Potts, R Behrensmeyer, AK AF Sikes, NE Potts, R Behrensmeyer, AK TI Early Pleistocene habitat in Member 1 Olorgesailie based on paleosol stable isotopes SO JOURNAL OF HUMAN EVOLUTION LA English DT Article DE early hominids; stable isotopes; paleosol; Olorgesailie; paleolandscape; Pleistocene; Acheulean ID SOUTHERN KENYA RIFT; EAST-AFRICA; CARBON ISOTOPES; OXYGEN ISOTOPES; ATMOSPHERIC CO2; OLDUVAI GORGE; UNITED-STATES; LATE MIOCENE; FORT-TERNAN; SOILS AB Stable carbon and oxygen isotope values from soil carbonates were used to determine the vegetation context of archaeological sites and local climatic conditions represented in a similar to 0.99 Ma paleosol that is exposed laterally in the Olorgesailie basin, southern Kenya rift valley. As part of this landscape-scale project, samples of an upper Member 1 paleosol were analyzed along nearly 4 km of outcrop in three adjacent parts of the basin. Modem East African soil and plant community analogs are used to interpret. the isotope ratios. The carbon isotopic composition of the paleosol carbonates indicates that the area supported a local biomass of about 75-100% C-4 plants during the period of soil formation. After averaging the data for each trench, an open C-4 grassland is represented by half of the carbon values, with wooded grassland more abundant across the paleolandscape than it is in the area now. This vegetational reconstruction is supported by the mammalian faunal assemblage, which has a high percentage of grazers. Although the relatively small sample size outside the main excavation area precludes firm characterization of vegetational diversity across the basin in upper Member 1 times, eastern and western localities in the study area may have had more woody C-3 plants than the widely sampled zone in between. Oxygen isotopes indicate that the lowland basin was slightly cooler and moister than today's semi-arid climate, with greater annual rainfall. Archaeological traces have a virtually continuous distribution across the paleolandscape, but vary in density of occurrence. With the strong evidence for C-4 grassland as the primary vegetation context across most of the study area, no habitat preference by the Acheulean toolmakers at Olorgesailie is shown in our initial comparison between carbon isotope values and stone/bone densities. (C) 1999 Academic Press. C1 Smithsonian Inst, Museum Support Ctr, Smithson Light Isotope Lab, Washington, DC 20560 USA. Smithsonian Inst, Museum Natl Hist Nat, Human Origins Program, Washington, DC 20560 USA. Smithsonian Inst, Museum Natl Hist Nat, Dept Paleobiol, Washington, DC 20560 USA. RP Sikes, NE (reprint author), Smithsonian Inst, Museum Support Ctr, Smithson Light Isotope Lab, Washington, DC 20560 USA. EM nsikes@scmre.si.edu; potts.rick@nmnh.si.edu; behrensmeyer.kay@nmnh.si.edu NR 97 TC 42 Z9 43 U1 0 U2 4 PU ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0047-2484 J9 J HUM EVOL JI J. Hum. Evol. PD NOV PY 1999 VL 37 IS 5 BP 721 EP 746 DI 10.1006/jhev.1999.0343 PG 26 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 254ZN UT WOS:000083644500002 PM 10536089 ER PT J AU Potts, R Behrensmeyer, AK Ditchfield, P AF Potts, R Behrensmeyer, AK Ditchfield, P TI Paleolandscape variation and Early Pleistocene hominid activities: Members 1 and 7, Olorgesailie Formation, Kenya SO JOURNAL OF HUMAN EVOLUTION LA English DT Article DE early hominid behavior; paleolandscape; land use; paleoecology; Olorgesailie; Acheulean; stone tools; fossilized bones; paleosol; fluvial deposition; taphonomy ID LAKE TURKANA BASIN; OLDUVAI GORGE; KOOBI-FORA; LAND-USE; BED-II; TANZANIA; RIFT AB Paleolandscape research tests for variation in the spatial distribution of hominid artefacts and establishes the association of hominid activities with paleoenvironmental features over distances of 100s to 1000s of meters. This approach requires (1) precise definition of narrow stratigraphic intervals based on sedimentary criteria that can be documented over a broad area, and (2) excavation of these intervals in order to establish taphonomic and paleoenvironmental contexts. In this report, excavations of three target intervals within the early Pleistocene deposits (992 to 780 ka) of the Olorgesailie basin are described. Assessment of time-averaging and paleolandscape structure shows that each target interval represents a relatively brief period (less than or equal to 1000 yrs) and exhibits a unique distribution of environmental features (e.g., topographic gradients, channels, soil development). Stone artefacts and fossilized animal bones are distributed nonrandomly in each interval, and include clusters that were five to 293 times more densely concentrated than the laterally equivalent background scatter. A paleosol in upper Member 1 preserves a relatively continuous distribution of artefacts and fossils, in contrast with the more patchy distribution in two intervals of lower Member 7. We infer that the difference between the two members reflects a real variation in hominid land use-either a response to local environmental differences or perhaps a change through time in hominid interaction with the environment. By expanding the comparative analysis to diverse basins, it should be possible to test for broader evolutionary change in hominid activities. Examples drawn from East African Pliocene and early Pleistocene sites suggest that evolutionary change in land use entailed (1) wider ranging of hominids and longer distances of stone transport, (2) expansion of tool-assisted behaviors to a wider diversity of environmental settings, and (3) more strongly focused placement of particular artefact forms (e.g., bifaces) in different areas of the landscape in response to specific environmental features, such as lava outcrops, stream channels, and lake margins. C1 Smithsonian Inst, Museum Natl Hist Nat, Human Origins Program, Washington, DC 20560 USA. Natl Museums Kenya, Div Paleontol, Nairobi, Kenya. Univ Bristol, Dept Geol, Bristol BS8 1RJ, Avon, England. RP Potts, R (reprint author), Smithsonian Inst, Museum Natl Hist Nat, Human Origins Program, Washington, DC 20560 USA. EM potts.rick.@nmnh.si.edu; behrensmeyer.kay@nmnh.si.edu; p.ditchfield@bristol.ac.uk NR 45 TC 122 Z9 124 U1 2 U2 11 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0047-2484 J9 J HUM EVOL JI J. Hum. Evol. PD NOV PY 1999 VL 37 IS 5 BP 747 EP 788 DI 10.1006/jhev.1999.0344 PG 42 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 254ZN UT WOS:000083644500003 PM 10536090 ER PT J AU Shishkin, VS Hoffmann, RS AF Shishkin, VS Hoffmann, RS TI Vladimir Evgenevich Sokolov: 1928-1998 - Obituary SO JOURNAL OF MAMMALOGY LA English DT Biographical-Item C1 Russian Acad Sci, Severtsov Inst Ecol & Evolut, Moscow 117071, Russia. Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. RP Shishkin, VS (reprint author), Russian Acad Sci, Severtsov Inst Ecol & Evolut, Leninskii Prospekt 33, Moscow 117071, Russia. NR 1 TC 0 Z9 0 U1 1 U2 1 PU AMER SOC MAMMALOGISTS PI PROVO PA BRIGHAM YOUNG UNIV, DEPT OF ZOOLOGY, PROVO, UT 84602 USA SN 0022-2372 J9 J MAMMAL JI J. Mammal. PD NOV PY 1999 VL 80 IS 4 BP 1361 EP 1364 PG 4 WC Zoology SC Zoology GA V3327 UT WOS:000177533300028 ER PT J AU Korth, WW Chaney, DS AF Korth, WW Chaney, DS TI A new subfamily of geomyoid rodents (Mammalia) and a possible origin of Geomyidae SO JOURNAL OF PALEONTOLOGY LA English DT Article AB Two new species, Mojavemys galushai and Phelosaccomys neomexicanus are described from the Barstovian of New Mexico. Both of these species are assigned to a new subfamily, the Mojavemyinae. It is uncertain as to whether this new subfamily should be referred to the Heteromyidae or Geomyidae. Both Mojavemys an Phelosaccomys retain some heteromyid characteristics while developing advanced traits of geomyids. It is possible that these genera represent transitional forms between a heteromyid ancestor and advanced geomyines, thus deriving the Geomyidae directly from the Heteromyidae sometime in the middle Tertiary. It is also possible that the Mojavemyinae are a subfamily of heteromyids only convergent with geomyids. A third possibility is that the mojavemyines are among a group of middle Tertiary geomyoids from which both Recent heteromyids and geomyids were derived. C1 Rochester Inst Vertebrate Paleontol, Penfield, NY 14526 USA. SUNY Coll Buffalo, Dept Earth Sci & Sci Educ, Buffalo, NY 14222 USA. Smithsonian Inst, Natl Museum Nat Hist, Dept Paleobiol, Washington, DC 20560 USA. RP Korth, WW (reprint author), Rochester Inst Vertebrate Paleontol, 928 Whalen Rd, Penfield, NY 14526 USA. NR 26 TC 5 Z9 5 U1 0 U2 1 PU PALEONTOLOGICAL SOC INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044 USA SN 0022-3360 J9 J PALEONTOL JI J. Paleontol. PD NOV PY 1999 VL 73 IS 6 BP 1191 EP 1200 PG 10 WC Paleontology SC Paleontology GA 259DR UT WOS:000083879600015 ER PT J AU Dalling, JW Lovelock, CE Hubbell, SP AF Dalling, JW Lovelock, CE Hubbell, SP TI Growth responses of seedlings of two neotropical pioneer species to simulated forest gap environments SO JOURNAL OF TROPICAL ECOLOGY LA English DT Article DE allocation patterns; gap partitioning; growth analysis; light quality; Luehea; Ochroma; pioneer; simulated gap; tropical rain forest ID TROPICAL RAIN-FOREST; SPECTRAL QUALITY; TREE SEEDLINGS; CANOPY GAPS; LIGHT; RAINFOREST; HETEROGENEITY; REGENERATION; AVAILABILITY; MORPHOLOGY AB Traditional shade house experiments that expose plants to relatively uniform irradiance and light quality are inadequate to characterize the morphological, allocational and physiological plasticity that seedlings show to different gap environments. Here the design of a pot experiment is described that simulates the daily time course of irradiance and light quality in idealized gaps of six different sizes. Differences in response to gap size are illustrated using data from two pioneer species, Ochroma pyramidale, which recruits exclusively in large gaps and clearings, and Luehea seemannii, which colonizes small branchfall gaps as well as large gaps. Ochroma outperformed Luehea in relative growth rate in all except the smallest simulated gap size. Ochroma's superior performance in the larger gaps could be attributed to a larger proportional investment in leaf biomass (i.e. a higher leaf area ratio, LAR), and higher photosynthetic rates both on a leaf area and leaf mass basis. In the smallest simulated gaps LAR was not significantly different between the species, but Ochroma maintained a higher net assimilation rate. These results fail to support the suggestion that gap partitioning among pioneer species arises directly from morphological and biochemical specialization to particular gap light environments. Instead, it is suggested that partitioning may result from a trade-off between seedling growth and mortality determined by species allocational patterns and mediated by interactions with herbivores and pathogens. C1 Smithsonian Trop Res Inst, Balboa, Panama. RP Dalling, JW (reprint author), Smithsonian Trop Res Inst, Apartado 2072, Balboa, Panama. RI Lovelock, Catherine/G-7370-2012 OI Lovelock, Catherine/0000-0002-2219-6855 NR 41 TC 29 Z9 31 U1 0 U2 10 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0266-4674 J9 J TROP ECOL JI J. Trop. Ecol. PD NOV PY 1999 VL 15 BP 827 EP 839 DI 10.1017/S0266467499001200 PN 6 PG 13 WC Ecology SC Environmental Sciences & Ecology GA 283AK UT WOS:000085253800009 ER PT J AU Kalfatovic, MR AF Kalfatovic, MR TI Art: The critics' choice; 150 masterpieces of western art. SO LIBRARY JOURNAL LA English DT Book Review C1 Smithsonian Inst Lib, Washington, DC 20560 USA. RP Kalfatovic, MR (reprint author), Smithsonian Inst Lib, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU BOWKER MAGAZINE GROUP CAHNERS MAGAZINE DIVISION PI NEW YORK PA 249 W 17TH ST, NEW YORK, NY 10011 USA SN 0363-0277 J9 LIBR J JI Libr. J. PD NOV 1 PY 1999 VL 124 IS 18 BP 76 EP 76 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 250MY UT WOS:000083393200042 ER PT J AU Kalfatovic, MR AF Kalfatovic, MR TI The informed eye: Understanding masterpieces of western art. SO LIBRARY JOURNAL LA English DT Book Review C1 Smithsonian Inst Lib, Washington, DC 20560 USA. RP Kalfatovic, MR (reprint author), Smithsonian Inst Lib, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU BOWKER MAGAZINE GROUP CAHNERS MAGAZINE DIVISION PI NEW YORK PA 249 W 17TH ST, NEW YORK, NY 10011 USA SN 0363-0277 J9 LIBR J JI Libr. J. PD NOV 1 PY 1999 VL 124 IS 18 BP 76 EP 76 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 250MY UT WOS:000083393200041 ER PT J AU Thiel, M AF Thiel, M TI Reproductive biology of a wood-boring isopod, Sphaeroma terebrans, with extended parental care SO MARINE BIOLOGY LA English DT Article ID INDIAN-RIVER LAGOON; PARACERCEIS-SCULPTA; CRUSTACEA; AMPHIPOD; COROPHIOIDEA; ASSOCIATION; AMPITHOIDAE; SERRATUM; NORTHERN; ECOLOGY AB The isopod Sphaeroma terebrans Bate, 1866 burrows in aerial roots of the red mangrove Rhizophora mangle L. The burrows serve as shelter and as a reproductive habitat, and females are known to host their offspring in their burrows. I examined the reproductive biology of S. terebrans in the Indian River Lagoon, a shallow lagoon stretching for similar to 200 km along the Atlantic coast of Florida, USA. Reproductive isopods were found throughout the year, but reproductive activity was highest in the fall and during late spring/early summer. During the latter periods, large numbers of subadults established their own burrows in aerial roots. The average numbers of S. tereblans per root were high during the fall, but decreased during the winter and reached lowest levels at the end of the summer. Females reached maturity at a larger size than males, but also grew to larger sizes than the males. The average size of females varied between 8 and 10 mm, the average size of males between 6.5 and 8.5 mm. The number of embryos female(-1) was strongly correlated with female body length. No indication for embryo mortality during development was found. Parental females (i.e. with juveniles in their burrows) hosted on average between 5 and 20 juveniles in their burrows (range 1 to 59). Most juveniles found in female burrows were in the manca stage and 2 to 3 mm in body length. Juveniles did not increase in size while in the maternal burrow, and juveniles of similar sizes could also be found in their own burrows. Males did not participate in extended parental care, since most of them left the females after copulation. Many females that were born in the summer produced one brood in the fall and a second during winter/early spring. Females that were born in the fall produced one brood during spring/early summer, but then probably died. Extended parental care in S. terebrans is short compared to other peracarid crustaceans. It is concluded that this reproductive strategy in S. terebrans serves primarily to shelter small juveniles immediately after they emerge from the female body, when their exoskeleton is still hardening and their physiological capabilities are still developing. Thus, in S. terebrans, extended parental care probably aids to protect small juveniles from adverse physical conditions in their subtropical intertidal habitat. C1 Smithsonian Marine Stn, Ft Pierce, FL 34946 USA. RP Thiel, M (reprint author), Univ Catolica Norte, Fac Ciencias Mar, Larrondo 1281,Campus Guayacan, Coquimbo, Chile. NR 60 TC 17 Z9 19 U1 1 U2 13 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0025-3162 J9 MAR BIOL JI Mar. Biol. PD NOV PY 1999 VL 135 IS 2 BP 321 EP 333 DI 10.1007/s002270050630 PG 13 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 258KW UT WOS:000083839200013 ER PT J AU Erbacher, J Hemleben, C Huber, BT Markey, M AF Erbacher, J Hemleben, C Huber, BT Markey, M TI Correlating environmental changes during early Albian oceanic anoxic event 1B using benthic foraminiferal paleoecology SO MARINE MICROPALEONTOLOGY LA English DT Article DE benthic foraminifera; oceanic anoxic events; Cretaceous; black shales; ODP leg 171B; SE France Basin ID CENOMANIAN-TURONIAN BOUNDARY; CARBON-ISOTOPE STRATIGRAPHY; ORGANIC-MATTER; NORTH-ATLANTIC; SERGIPE BASIN; BLACK SHALES; SE FRANCE; EVOLUTION; PATTERNS; BIOSTRATIGRAPHY AB The nature and consequences of mid-Cretaceous oceanic anoxic events (OAEs) are the subject of ongoing debate, and recent studies have shown that different scenarios are needed to explain each of these events. Nevertheless, similarities between the different OAEs can be observed. Here, we have reconstructed paleoenvironmental changes during the early Albian OAE Ib using benthic foraminiferal distributions and lithologies in three sections from different basins and paleowater depths. Eutrophic conditions, as indicated by the presence of infaunal as well as opportunistic genera such as Gyroidinoides, Pseudobolivina, Pleurostomella and bolivinitids, prevailed before and during the OAE and led to dysoxic to anoxic conditions. Dysoxia was most intense in the bathyal sections but also occurred in the outer shelf where more heterogeneous patterns of foraminiferal distributions are believed to reflect fluctuations of the upper boundary of an oxygen-minimum zone. A change from eutrophic to mesotrophic conditions caused the termination of OAE Ib and opportunistic benthic foraminifera (e.g. Pseudobolivina, Pleurostomella) were the first to subsequently repopulate the bathyal sea floor. Repopulation occurred rapidly in the shallow settings and gradually in the deeper sites, where a normal, diverse pre-event fauna was established a few tens of thousands of years after OAE Ib. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Bundesanstalt Geowissensch & Rohstoffe, Referat Meeresgeol, D-30655 Hannover, Germany. Univ Tubingen, Inst Geol & Palaontol, D-72076 Tubingen, Germany. Univ Tubingen, Museum Geol & Palaontol, D-72076 Tubingen, Germany. Natl Museum Nat Hist, Dept Paleobiol, Smithsonian Inst, Washington, DC 20560 USA. RP Erbacher, J (reprint author), Bundesanstalt Geowissensch & Rohstoffe, Referat Meeresgeol, Stilleweg 2, D-30655 Hannover, Germany. EM erbacher@bgr.de NR 72 TC 56 Z9 61 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-8398 J9 MAR MICROPALEONTOL JI Mar. Micropaleontol. PD NOV PY 1999 VL 38 IS 1 BP 7 EP 28 DI 10.1016/S0377-8398(99)00036-5 PG 22 WC Paleontology SC Paleontology GA 258KP UT WOS:000083838600002 ER PT J AU Krajewski, C Fain, MG Buckley, L KIng, DG AF Krajewski, C Fain, MG Buckley, L KIng, DG TI Dynamically heterogenous partitions and phylogenetic inference: An evaluation of analytical strategies with cytochrome b and ND6 gene sequences in cranes SO MOLECULAR PHYLOGENETICS AND EVOLUTION LA English DT Article ID MAXIMUM-LIKELIHOOD; COMBINING DATA; DNA HYBRIDIZATION; SUBSTITUTION; GRUIDAE; GRUIFORMES; RATES; CHARACTERS; CONGRUENCE; HYPOTHESIS AB Debates over whether molecular sequence data should be partitioned for phylogenetic analysis often confound two types of heterogeneity among partitions. We distinguish historical heterogeneity (i.e., different partitions have different evolutionary relationships) from dynamic heterogeneity (i.e., different partitions show different patterns of sequence evolution) and explore the impact of the latter on phylogenetic accuracy and precision with a two-gene, mitochondrial data set for cranes. The well-established phylogeny of cranes allows us to contrast tree-based estimates of relevant parameter values with estimates based on pairwise comparisons and to ascertain the effects of incorporating different amounts of process information into phylogenetic estimates. We show that codon positions in the cytochrome b and NADH dehydrogenase subunit 6 genes are dynamically heterogenous under both Poisson and invariable-sites + gamma-rates Versions of the F84 model and that heterogeneity includes variation in base composition and transition bias as well as substitution rate. Estimates of transition bias and relative-rate parameters from pairwise sequence comparisons were comparable to those obtained as tree-based maximum likelihood estimates. Neither rate-category nor mixed-model partitioning strategies resulted in a loss of phylogenetic precision relative to unpartitioned analyses. We suggest that weighted-average distances provide a computationally feasible alternative to direct maximum likelihood estimates of phylogeny for mixed-model analyses of large, dynamically heterogenous data sets. (C) 1999 Academic Press. C1 So Illinois Univ, Dept Zool, Carbondale, IL 62901 USA. So Illinois Univ, Ctr Systemat Biol, Carbondale, IL 62901 USA. Smithsonian Inst, Museum Natl Hist Nat, Div Reptiles & Amphibians, Washington, DC 20560 USA. So Illinois Univ, Sch Med, Dept Anat, Carbondale, IL 62901 USA. RP Krajewski, C (reprint author), So Illinois Univ, Dept Zool, Carbondale, IL 62901 USA. NR 54 TC 18 Z9 21 U1 0 U2 2 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1055-7903 J9 MOL PHYLOGENET EVOL JI Mol. Phylogenet. Evol. PD NOV PY 1999 VL 13 IS 2 BP 302 EP 313 DI 10.1006/mpev.1999.0646 PG 12 WC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity GA 257MW UT WOS:000083786500007 PM 10603258 ER PT J AU Hershler, R Liu, HP Mulvey, M AF Hershler, R Liu, HP Mulvey, M TI Phylogenetic relationships within the aquatic snail genus Tryonia: Implications for biogeography of the North American southwest SO MOLECULAR PHYLOGENETICS AND EVOLUTION LA English DT Review ID LOWER COLORADO RIVER; RIBOSOMAL-RNA SEQUENCES; SIERRA-NEVADA; DEATH-VALLEY; MITOCHONDRIAL-DNA; SOUTHEASTERN CALIFORNIA; VICARIANCE BIOGEOGRAPHY; SOUTHERN-CALIFORNIA; EASTERN CALIFORNIA; BOUSE FORMATION AB We examined the phylogenetic relationships among 23 species of the North American aquatic snail genus Tryonia (Hydrobiidae), 10 additional representatives of the subfamily Cochliopinae, and two outgroups. Maximum parsimony analysis of a 601-base-pair sequence from the mitochondrial COI gene did not support monophyly of the genus nor its subgenus Paupertryonia. A clade composed of the type species of Tryonia and 16 congeners was strongly supported by the COI data and congruent with recently discovered variation in female genitalic morphology. This "true Tryonia" clade included two large western subclades having a sister-group relationship. The phylogenetic: structure of one of these subclades is congruent with vicariant events associated with late Neogene history of the lower Colorado River drainage. The other subclade mirrors development of the modern Rio Grande rift and inception of modern topography in the southwestern Great Basin during the late Neogene, Both subclades are represented in the composite Tryonia fauna of the Amargosa River basin, whose assembly is attributed to the complex geological history of the Death Valley region. (C) 1999 Academic Press. C1 Smithsonian Inst, Museum Natl Hist Nat, Dept Invertebrate Zool, Washington, DC 20560 USA. SW Missouri State Univ, Dept Biol, Springfield, MO 65804 USA. Virginia Inst Marine Sci, Dept Environm Sci, Gloucester Point, VA 23062 USA. RP Hershler, R (reprint author), Smithsonian Inst, Museum Natl Hist Nat, Dept Invertebrate Zool, Washington, DC 20560 USA. NR 111 TC 41 Z9 41 U1 0 U2 7 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1055-7903 J9 MOL PHYLOGENET EVOL JI Mol. Phylogenet. Evol. PD NOV PY 1999 VL 13 IS 2 BP 377 EP 391 DI 10.1006/mpev.1999.0659 PG 15 WC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity GA 257MW UT WOS:000083786500014 PM 10603265 ER PT J AU Heyman, IM AF Heyman, IM TI This view of Stephen Jay Gould SO NATURAL HISTORY LA English DT Biographical-Item C1 Smithsonian Inst, Washington, DC 20560 USA. RP Heyman, IM (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER MUSEUM NAT HISTORY PI NEW YORK PA ATTN: LIBRARY SERIALS UNIT CENTRAL PK WEST AT 79TH ST, NEW YORK, NY 10024-5192 USA SN 0028-0712 J9 NAT HIST JI Nat. Hist. PD NOV PY 1999 VL 108 IS 9 BP 51 EP 51 PG 1 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 261BF UT WOS:000083987400019 ER PT J AU Fonseca, DM AF Fonseca, DM TI Fluid-mediated dispersal in streams: models of settlement from the drift SO OECOLOGIA LA English DT Article DE stream drift; settlement constraints; predictive models; current speed; simuliidae ID BLACK FLIES DIPTERA; SUPPLY-SIDE ECOLOGY; CURRENT VELOCITY; LARVAL SETTLEMENT; FIELD EXPERIMENTS; INGESTION RATES; MARINE; SIMULIIDAE; FLOW; INVERTEBRATES AB I propose proximal mechanisms that help explain, unify, and expand the predictions of widely accepted empirical models of settlement in streams. I separated the process that leads to settlement of a drifting particle into three stages: (1) initial contact with a substrate, (2) attachment, and (3) settlement sensu stricto. I used physical principles (height above the bed, sinking rate, current speed profile) to predict time until contact (stage 1). I compared these predictions with empirical measurements of settlement of individual black fly larvae (Simulium vittatum) in a laboratory flume. I developed models from empirical data for stages 2 and 3. Each of these models is individual-based and predicts the fate of a single individual. To obtain a population level prediction, models for the three stages were combined and used to simulate the settlement of a group of black fly larvae. The predictions of this simulation were qualitatively similar to population level data from the literature particularly after the incorporation of channel-wide spatial heterogeneity in current speed. The effect of flow heterogeneity on the model agrees with previous work on the lateral transport of stream invertebrates during drift events showing that many organisms settle preferentially in slower areas. By using proximal principles, the approach used in this study brings into focus basic parameters and processes that influence settlement at the scale of the organisms. It also provides a null hypothesis against which to study the effect of local flow heterogeneity on the settlement of stream invertebrates and the capacity of organisms to actively influence settlement. Water currents in streams and rivers commonly transport large numbers of organisms. Consequently, hydrodynamic factors that favor or hamper the settlement of these organisms can potentially influence distributions and abundance. Moreover, if settlement probabilities vary with flow characteristics, this can in turn influence foraging strategies that rely on fluid-mediated dispersal. C1 Univ Penn, Dept Biol, Philadelphia, PA 19104 USA. Smithsonian Inst, Museum Support Ctr, Walter Reed Biosystemat Unit, MRC 534, Suitland, MD 20746 USA. RP Fonseca, DM (reprint author), Walter Reed Army Med Ctr, Walter Reed Army Inst Res, Div Communicable Dis & Immunol, Dept Entomol, Washington, DC 20307 USA. RI Fonseca, Dina/B-9951-2011 OI Fonseca, Dina/0000-0003-4726-7100 NR 58 TC 32 Z9 34 U1 2 U2 14 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0029-8549 J9 OECOLOGIA JI Oecologia PD NOV PY 1999 VL 121 IS 2 BP 212 EP 223 DI 10.1007/s004420050923 PG 12 WC Ecology SC Environmental Sciences & Ecology GA 258NY UT WOS:000083846300008 PM 28308561 ER PT J AU Meinzer, FC Andrade, JL Goldstein, G Holbrook, NM Cavelier, J Wright, SJ AF Meinzer, FC Andrade, JL Goldstein, G Holbrook, NM Cavelier, J Wright, SJ TI Partitioning of soil water among canopy trees in a seasonally dry tropical forest SO OECOLOGIA LA English DT Article DE roots; sap flow; leaf phenology; stable hydrogen isotope ratio; panama ID HYDRAULIC LIFT; EUCALYPTUS-CAMALDULENSIS; STREAM WATER; PLANTS; MOVEMENT; HYDROGEN; BALANCE; SHRUBS AB Little is known about partitioning of soil water resources in species-rich, seasonally dry tropical fc,rests. We assessed spatial and temporal patterns of soil water utilization in several canopy tree species on Barro Colorado Island, Panama, during the 1997 dry season. Stable hydrogen isotope composition (delta D) of xylem and soil water, soil volumetric water content (theta(v)), and sap flow were measured concurrently. Evaporative fractionation near the soil surface caused soil water delta D to decrease from about -15 parts per thousand at 0.1 m to -50 to -55 parts per thousand at 1.2 m depth. Groundwater sampled at the sources of nearby springs during this period yielded an average FD value of -60 parts per thousand. theta(v) increased sharply and nearly linearly with depth to 0.7 m, then increased more slowly between 0.7 and 1.05 m. Based on xylem delta D values, water uptake in some individual plants appeared to be restricted largely to the upper 20 cm of the soil profile where theta(v) dropped below 20% during the dry season. In contrast, other individuals appeared to have access to water at depths greater than 1 m where theta(v) remained above 45% throughout the dry season. The depths of water sources for trees with intermediate xylem delta D values were less certain because variation in soil water delta D between 20 and 70 cm was relatively small. Xylem water delta D was also strongly dependent on tree size (diameter at breast height), with smaller trees appearing to preferentially tap deeper sources of soil water than larger trees. This relationship appeared to be species independent. Trees able to exploit progressively deeper sources of soil water during the dry season, as indicated by increasingly negative xylem delta D values, were also able to maintain constant or even increase rates of water use. Seasonal courses of water use and soil water partitioning were associated with leaf phenology. Species with the smallest seasonal variability in leaf fall were also able to tap increasingly deep sources of soil water as the dry season progressed. Comparison of xylem, soil, and groundwater delta D values thus pointed to spatial and temporal partitioning of water resources among several tropical forest canopy tree species during the dry season. C1 Hawaii Agr Res Ctr, Aiea, HI 96701 USA. Univ Hawaii, Dept Bot, Honolulu, HI 96822 USA. Harvard Univ, Biol Labs, Cambridge, MA 02138 USA. Univ Los Andes, Dept Ciencias Biol, Bogota, Colombia. Smithsonian Trop Res Inst, Balboa, Ancon, Panama. RP Meinzer, FC (reprint author), Hawaii Agr Res Ctr, 99-193 Aiea Heights Dr,Suite 300, Aiea, HI 96701 USA. RI Meinzer, Frederick/C-3496-2012; Wright, Stuart/M-3311-2013 OI Wright, Stuart/0000-0003-4260-5676 NR 31 TC 132 Z9 147 U1 6 U2 58 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0029-8549 J9 OECOLOGIA JI Oecologia PD NOV PY 1999 VL 121 IS 3 BP 293 EP 301 DI 10.1007/s004420050931 PG 9 WC Ecology SC Environmental Sciences & Ecology GA 261RC UT WOS:000084021700001 PM 28308316 ER PT J AU Hinman, RL AF Hinman, RL TI Scientific literacy revisited SO PHI DELTA KAPPAN LA English DT Article C1 Smithsonian Inst & Natl Acad Sci, Advisory Council, Natl Sci Resource Ctr, Washington, DC 20560 USA. Pfizer Inc, Pfizer Cent Res, Groton, CT 06340 USA. RP Hinman, RL (reprint author), Smithsonian Inst & Natl Acad Sci, Advisory Council, Natl Sci Resource Ctr, Washington, DC 20560 USA. NR 12 TC 1 Z9 1 U1 0 U2 0 PU PHI DELTA KAPPA PI BLOOMINGTON PA 8TH AND UNION P O BOX 789, BLOOMINGTON, IN 47402 USA SN 0031-7217 J9 PHI DELTA KAPPAN JI Phi Delta Kappan PD NOV PY 1999 VL 81 IS 3 BP 239 EP 241 PG 3 WC Education & Educational Research SC Education & Educational Research GA 253HY UT WOS:000083552100014 ER PT J AU Esry, BD Sadeghpour, HR AF Esry, BD Sadeghpour, HR TI Adiabatic formulation of heteronuclear hydrogen molecular ion SO PHYSICAL REVIEW A LA English DT Article ID HD DIPOLE-MOMENT; MICROWAVE SPECTROSCOPY; SYMMETRY-BREAKING; RYDBERG STATES; POLARIZABILITIES; FRACTIONATION; APPROXIMATION; DISSOCIATION; H-2+ AB We revisit the HD+ molecular ion by starting from a definition of the nonrelativistic adiabatic Hamiltonian that recovers the isotopic splitting. The Hamiltonian is written in prolate spheroidal coordinates with the origin at the nuclear center of mass. This prescription for the adiabatic Hamiltonian implicitly contains the symmetry-breaking effects arising from the mass difference between the proton and the deuteron, and gives the correct asymptotic atomic reduced masses. We calculate potential-energy curves, vibrational energies, transition dipole moments, and coupling matrix elements for HD+. In our adiabatic approximation, the isotopic splitting is recovered to nine significant digits at a value of R = 750a(0). We investigate the dependence of the vibrational energies on the number of coupled electronic states, and compare with other calculations. [S1050-2947(99)07311-4]. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Esry, BD (reprint author), Kansas State Univ, Dept Phys, Cardwell Hall, Manhattan, KS 66504 USA. RI Esry, Brett/H-7511-2013 OI Esry, Brett/0000-0003-3207-8526 NR 39 TC 54 Z9 55 U1 2 U2 11 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD NOV PY 1999 VL 60 IS 5 BP 3604 EP 3617 DI 10.1103/PhysRevA.60.3604 PG 14 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 257ED UT WOS:000083768800041 ER PT J AU Foote, T AF Foote, T TI 'Fencing the Sky' SO NEW YORK TIMES BOOK REVIEW LA English DT Book Review C1 Smithsonian Magazine, Washington, DC USA. RP Foote, T (reprint author), Smithsonian Magazine, Washington, DC USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU NEW YORK TIMES PI NEW YORK PA 229 W 43RD ST, NEW YORK, NY 10036-3959 USA SN 0028-7806 J9 NY TIMES BK REV JI N. Y. Times Book Rev. PD OCT 31 PY 1999 BP 22 EP 22 PG 1 WC Humanities, Multidisciplinary SC Arts & Humanities - Other Topics GA 248CL UT WOS:000083257700016 ER PT J AU Soon, W Baliunas, SL Robinson, AB Robinson, ZW AF Soon, W Baliunas, SL Robinson, AB Robinson, ZW TI Environmental effects of increased atmospheric carbon dioxide SO CLIMATE RESEARCH LA English DT Review DE global warming; carbon dioxide; atmospheric and biological effects ID SURFACE AIR-TEMPERATURE; GENERAL-CIRCULATION MODELS; MEDIEVAL WARM PERIOD; LATITUDE-TEMPORAL FIELDS; GCM CLIMATE VARIABILITY; SOUR ORANGE TREES; SEA-LEVEL RISE; CO2 ENRICHMENT; WATER-VAPOR; INTERCOMPARISON PROJECT AB A review of the Literature concerning the environmental consequences of increased levels of atmospheric carbon dioxide leads to the conclusion that increases during the 20th century have produced no deleterious effects upon global climate or temperature. Increased carbon dioxide has, however, markedly increased plant growth rates as inferred from numerous laboratory and held experiments. There is no clear evidence, nor unique attribution, of the global effects of anthropogenic CO2 on climate. Meaningful integrated assessments of the environmental impacts of anthropogenic CO2 are not yet possible because model estimates of global and regional climate changes on interannual, decadal and centennial time scales remain highly uncertain. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Oregon Inst Sci & Med, Cave Junction, OR 97523 USA. RP Soon, W (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 159 TC 19 Z9 20 U1 5 U2 41 PU INTER-RESEARCH PI OLDENDORF LUHE PA NORDBUNTE 23, D-21385 OLDENDORF LUHE, GERMANY SN 0936-577X J9 CLIMATE RES JI Clim. Res. PD OCT 26 PY 1999 VL 13 IS 2 BP 149 EP 164 DI 10.3354/cr013149 PG 16 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 277DM UT WOS:000084917500006 ER PT J AU Whyte, A Yang, ZC Tiyanont, K Weldon, PJ Eisner, T Meinwald, J AF Whyte, A Yang, ZC Tiyanont, K Weldon, PJ Eisner, T Meinwald, J TI Reptilian chemistry: Characterization of dianeackerone, a secretory product from a crocodile SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE Osteolaemus tetraspis; paracloacal gland; pheromone; stereospecific synthesis ID PARACLOACAL GLAND SECRETIONS; ALLIGATOR ALLIGATOR-SINENSIS; LIPIDS; TRIGONATUS AB The major volatile component in the paracloacal glandular secretion of the adult African dwarf crocodile (Osteolaemus tetraspis) was isolated and characterized as a 19-carbon aromatic: ketone, dianeackerone (3,7-diethyl-9-phenyl-2-nonanone). This ketone is absent from the secretion of immatures. Careful examination of dianeackerone samples isolated from individual adults revealed that this ketone occurs as both the (3S, 7S) and (3S, 7R) stereoisomers, with different individuals presenting strikingly different ratios of the isomeric forms. Our initial suspicion that the stereoisomeric dianeackerones might he indicators of gender proved untenable, leaving the role of these glandular constituents a challenge for future study. C1 Cornell Univ, Baker Lab, Dept Chem & Biol Chem, Ithaca, NY 14853 USA. Smithsonian Inst, Conservat & Res Ctr, Front Royal, VA 22630 USA. Cornell Univ, Neurobiol & Behav Sect, Ithaca, NY 14853 USA. RP Meinwald, J (reprint author), Cornell Univ, Baker Lab, Dept Chem & Biol Chem, Ithaca, NY 14853 USA. FU NIAID NIH HHS [R01 AI002908]; NIGMS NIH HHS [R01 GM053830] NR 11 TC 13 Z9 13 U1 5 U2 10 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD OCT 26 PY 1999 VL 96 IS 22 BP 12246 EP 12250 DI 10.1073/pnas.96.22.12246 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 250DD UT WOS:000083373000011 PM 10535906 ER PT J AU Yang, ZC Whyte, A Attygalle, AB Weldon, PJ Eisner, T Meinwald, J AF Yang, ZC Whyte, A Attygalle, AB Weldon, PJ Eisner, T Meinwald, J TI Reptilian chemistry: Characterization of a family of dianeackerone-related steroidal esters from a crocodile secretion SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE osteolaemus tetraspis; paracloacal gland; cholesterol; biosynthesis ID PARACLOACAL GLAND SECRETIONS; ALLIGATOR ALLIGATOR-SINENSIS; LIPIDS; TRIGONATUS AB The African dwarf crocodile, Osteolaemus tetraspis (Crocodilidae. Reptilia), possesses a pair of skin glands, the paracloacal glands, the secretion of which is thought to be used to mark nest sites or attract mates. Ten aromatic steroidal esters were isolated from this secretion and characterized on the basis of NMR spectroscopic investigations. electrospray ionization-MS analyses, and chemical degradation. These esters, which account for more than 90% of the paracloacal glandular secretion, are derived from either cholesterol or cholestanol, esterified with a C-20 or C-22 acid closely related to dianeackerone, the only significant volatile compound found in this secretion. C1 Cornell Univ, Baker Lab, Dept Chem & Biol Chem, Ithaca, NY 14853 USA. Smithsonian Inst, Conservat & Res Ctr, Front Royal, VA 22630 USA. Cornell Univ, Dept Neurobiol & Behav, Ithaca, NY 14853 USA. RP Meinwald, J (reprint author), Cornell Univ, Baker Lab, Dept Chem & Biol Chem, Ithaca, NY 14853 USA. FU NIGMS NIH HHS [R01 GM053830, GM53830] NR 7 TC 11 Z9 11 U1 0 U2 2 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD OCT 26 PY 1999 VL 96 IS 22 BP 12251 EP 12256 DI 10.1073/pnas.96.22.12251 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 250DD UT WOS:000083373000012 PM 10535907 ER PT J AU McCarthy, MC Apponi, AJ Thaddeus, P AF McCarthy, MC Apponi, AJ Thaddeus, P TI A second rhomboidal isomer of SiC3 SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article AB A second low-lying cyclic isomer of SiC3 has been detected in a supersonic molecular beam by Fourier transform microwave spectroscopy. Calculated to lie about 5 kcal above the ground state rhomboid, the new isomer is also a planar rhomboid with a transannular bond, C-2 upsilon symmetry, and a singlet electronic ground state. The transannular bond, however, is between the Si and the opposite C, and the rotational spectrum as a result is that of an oblate, not a prolate, asymmetric rotor. Both rhomboidal isomers of SiC3 are produced with comparable abundance under a wide range of experimental conditions, which suggests that cyclic isomers of longer silicon carbides may now be observable with the present techniques. Oblate SiC3 is a plausible molecule for astronomical detection because it is calculated to be fairly polar, and because radio emission lines of the ground state rhomboid have already been detected in the circumstellar shell of the evolved carbon star IRC + 10216. (C) 1999 American Institute of Physics. [S0021-9606(99)02840-8]. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. RP McCarthy, MC (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. OI McCarthy, Michael/0000-0001-9142-0008 NR 11 TC 43 Z9 43 U1 1 U2 5 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 OCT 22 PY 1999 VL 111 IS 16 BP 7175 EP 7178 DI 10.1063/1.480044 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 244LG UT WOS:000083052100001 ER PT J AU White, NE Tananbaum, H AF White, NE Tananbaum, H TI The Constellation X-ray mission SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 7th International Conference on Solid State Detectors CY DEC 04-06, 1998 CL NARA, JAPAN SP Crest, Japan Sci & Technol Corp DE X-ray astronomy; X-ray spectroscopy AB The Constellation-X mission is a large collecting area X-ray facility, emphasizing observations at high spectral resolution (E/Delta E similar to 300-3000) while covering a broad energy band (0.25-40 keV). By increasing the telescope aperture and utilizing efficient spectrometers the mission will achieve a factor of 100 increased sensitivity over current high-resolution X-ray spectroscopy missions. The use of focussing optics across the 10-40 keV band will provide a similar factor of 100 increased sensitivity in this band. Key technologies under development for the mission include lightweight high throughput X-ray optics, multilayer coatings to enhance the hard X-ray performance of X-ray optics, microcalorimeter spectrometer arrays with 2 eV resolution, low-power and low-weight CCD arrays, lightweight gratings and hard X-ray detectors. When observations commence towards the end of the next decade, Constellation-X will address many pressing questions concerning the extremes of gravity and the evolution of the Universe. (C) 1999 Elsevier Science B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP White, NE (reprint author), NASA, Goddard Space Flight Ctr, Code 662, Greenbelt, MD 20771 USA. RI White, Nicholas/B-6428-2012 OI White, Nicholas/0000-0003-3853-3462 NR 8 TC 3 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD OCT 21 PY 1999 VL 436 IS 1-2 BP 201 EP 204 DI 10.1016/S0168-9002(99)00621-X PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 241TD UT WOS:000082897900031 ER PT J AU Loeb, A Rybicki, GB AF Loeb, A Rybicki, GB TI Scattered Ly alpha radiation around sources before cosmological reionization SO ASTROPHYSICAL JOURNAL LA English DT Article ID GUNN-PETERSON TROUGH; GALAXY; FLOWS AB The spectra of the first galaxies and quasars in the universe should be strongly absorbed shortward of their rest-frame Ly alpha wavelength by neutral hydrogen (HI) in the intervening intergalactic medium. However, the Ly alpha line photons emitted by these sources are not eliminated but rather scatter until they redshift out of resonance and escape owing to the Hubble expansion of the surrounding intergalactic H I. We calculate the resulting brightness distribution and the spectral shape of the diffuse Ly alpha line emission around high-redshift sources before the intergalactic medium was reionized. Typically, the Ly alpha photons emitted by a source at z(s) similar to 10 scatter over a characteristic angular radius of similar to 15 " around the source and compose a line that is broadened and redshifted by similar to 10(3) km s(-1) relative to the source. The scattered photons are highly polarized. Detection of the diffuse Ly alpha halos around high-redshift sources would provide a unique tool for probing the neutral intergalactic medium before the epoch of reionization. On sufficiently large scales, where the Hubble how is smooth and the gas is neutral, the Ly alpha brightness distribution can be used to determine the cosmological mass densities of baryons and matter. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Loeb, A (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 35 TC 137 Z9 137 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 OCT 20 PY 1999 VL 524 IS 2 BP 527 EP 535 DI 10.1086/307844 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 245YB UT WOS:000083135300004 ER PT J AU Peng, CY Impey, CD Falco, EE Kochanek, CS Lehar, J McLeod, BA Rix, HW Keeton, CR Munoz, JA AF Peng, CY Impey, CD Falco, EE Kochanek, CS Lehar, J McLeod, BA Rix, HW Keeton, CR Munoz, JA TI The quasar pair Q1634+267A,B and the binary QSO versus dark lens hypotheses SO ASTROPHYSICAL JOURNAL LA English DT Article DE gravitational lensing; quasars : general; quasars : individual (Q1634+267) ID GRAVITATIONAL LENS; ENERGY-DISTRIBUTIONS; EQUATORIAL FIELDS; CONTINUUM SLOPES; CANDIDATE; DISCOVERY; GALAXIES; SPECTRA; RADIO; EMISSION AB Deep HST/NICMOS H-band (F160W) observations of the z = 1.96 quasar pair Q1634+267A and B reveal no signs of a lens galaxy to a 1 sigma threshold of similar or equal to 22.5 mag. The minimum luminosity for a normal lens galaxy would be a 6L* galaxy at z similar or equal to 0.5, which is 650 times greater than our detection threshold. Our observation constrains the infrared mass-to-light ratio (MIL) of any putative, early-type, lens galaxy to (MIL), greater than or similar to 690 h(65) (1200 h(65)) for Omega(0) = 0.1 (1.0) and H(0) = 65 h(65) km s(-1) Mpc(-1). We would expect to detect a galaxy somewhere in the field because of the very strong Mg II absorption lines at z = 1.1262 in the Q1634+267A spectrum, but the HST H-band, I-band (F785LP), and V-band (F555W) images require that any associated galaxy be very underluminous less than or similar to 0.1L*(H) (1.0L*(I)) if it lies within less than or similar to 40 h(65)(-1) (100 h(65)(-1)) kpc from Q1634+267A and B. While the large image separation (3 ".85) and the lack of a lens galaxy strongly favor interpreting Q1634 + 267A and B as a binary quasar system, the spectral similarity remains a puzzle. We estimate that, at most, 0.06% of randomly selected quasar pairs would have spectra as similar to each other as the spectra of Q1634+267A and B. Moreover, spectral similarities observed for the 14 known quasar pairs are significantly greater than would be expected for an equivalent sample of randomly selected field quasars. Depending on how strictly we define similarity, we estimate that only 0.01%-3% of randomly drawn samples of 14 quasar pairs would have as many similar pairs as the observational sample. C1 Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Peng, CY (reprint author), Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. EM cyp@as.arizona.edu; cimpey@as.arizona.edu; farco@cfa.harvard.edu; ckochanek@cfa.harvard.edu; jlehar@cfa.harvard.edu; bmcleod@cfa.harvard.edu; rix@as.arizona.edu; ckeeton@as.arizona.edu; jmunoz@cfa.harvard.edu NR 68 TC 18 Z9 18 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 20 PY 1999 VL 524 IS 2 BP 572 EP 581 DI 10.1086/307860 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 245YB UT WOS:000083135300007 ER PT J AU Reid, MJ Readhead, ACS Vermeulen, RC Treuhaft, RN AF Reid, MJ Readhead, ACS Vermeulen, RC Treuhaft, RN TI The proper motion of Sagittarius A*. I. First VLBA results SO ASTROPHYSICAL JOURNAL LA English DT Article DE astrometry; black hole physics; Galaxies : fundamental parameters Galaxy : center; Galaxy : kinematics and dynamics ISM : individual (Sagittarius A*) ID GALAXY AB We observed Sgr A* and two extragalactic radio sources nearby in angle with the VLBA over a period of 2 yr and measured relative positions with an accuracy approaching 0.1 mas. The apparent proper motion of Sgr A* relative to J1745-283 is 5.90 +/- 0.4 mas yr(-1), almost entirely in the plane of the Galaxy. The effects of the orbit of the Sun around the Galactic center can account for this motion, and any residual proper motion of Sgr A*, with respect to extragalactic sources, is less than about 20 km s(-1). Assuming that Sgr A* is at rest at the center of the Galaxy, we estimate that the circular rotation speed in the Galaxy at the position of the Sun, Theta(0) is 219 +/- 20 km s(-1), scaled by R-0/8.0 kpc. Current observations are consistent with Sgr A* containing all of the nearly 2.6 x 10(6) M-circle dot deduced from stellar proper motions, in the form of a massive black hole. While the low luminosity of Sgr A*, for example, might possibly have come from a contact binary containing of order 10 M-circle dot the lack of substantial motion rules out a "stellar" origin for Sgr A*. The very slow speed of Sgr A* yields a lower limit to the mass of Sgr A* of about 1000 M-circle dot, Even for this mass, Sgr A* appears to be radiating at less than 0.1% of its Eddington limit. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Reid, MJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 22 TC 184 Z9 187 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 OCT 20 PY 1999 VL 524 IS 2 BP 816 EP 823 DI 10.1086/307855 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 245YB UT WOS:000083135300025 ER PT J AU Rosolowsky, EW Goodman, AA Wilner, DJ Williams, JP AF Rosolowsky, EW Goodman, AA Wilner, DJ Williams, JP TI The spectral correlation function: A new tool for analyzing spectral line maps SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : structure; line : profiles; MHD; methods : statistical; molecular data; turbulence ID MOLECULAR CLOUDS; TURBULENCE; SCALE AB The "spectral correlation function" analysis we introduce in this paper is a new tool for analyzing spectral line data cubes. Our initial tests, carried out on a suite of observed and simulated data cubes, indicate that the spectral correlation function (SCF) is likely to be a more discriminating statistic than other statistical methods normally applied. The SCF is a measure of similarity between neighboring spectra in the data cube. When the SCF is used to compare a data cube consisting of spectral line observations of the interstellar medium (ISM) with a data cube derived from MI-ID simulations of molecular clouds, it can find differences that are not found by other analyses. The initial results presented here suggest that the inclusion of self-gravity in numerical simulations is critical for reproducing the correlation behavior of spectra in star-forming molecular clouds. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Rosolowsky, EW (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Williams, Jonathan/B-1643-2009; Goodman, Alyssa/A-6007-2010; OI Goodman, Alyssa/0000-0003-1312-0477; Williams, Jonathan/0000-0001-5058-695X NR 24 TC 67 Z9 67 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 OCT 20 PY 1999 VL 524 IS 2 BP 887 EP 894 DI 10.1086/307863 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 245YB UT WOS:000083135300031 ER PT J AU Kashyap, V Drake, JJ AF Kashyap, V Drake, JJ TI On X-ray variability in active binary stars SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : close; stars : activity; stars : coronae; X-rays : stars ID MEDIUM-SENSITIVITY SURVEY; ORBITAL PERIOD VARIATION; MAIN-SEQUENCE STARS; EXTREME-ULTRAVIOLET; ACTIVITY CYCLE; SOLAR-CYCLE; EMISSION; DYNAMO; TEMPERATURES; PHOTOMETRY AB We have compared the X-ray emissions of active binary stars observed at various epochs by the Einstein and ROSAT satellites in order to investigate the nature of their X-ray variability. The primary aim of this work is to determine whether or not active binaries exhibit long-term variations in X-ray emission, perhaps analogous to the observed cyclic behavior of solar magnetic activity. We find that, while the mean level of emission of the sample remains steady, comparison of different ROSAT observations of the same stars shows significant variation on timescales less than or similar to 2 yr, with an "effective variability" Delta I/I = 0.32 +/- 0.04, where I and AI represent the mean emission and variation from the mean emission, respectively. A comparison of the ROSAT All-Sky Survey and later pointed observations with earlier observations of the same stars carried out with Einstein yields only marginal evidence for a larger variation (Delta I/I = 0.38 +/- 0.04 for Einstein vs. ROSAT All-Sky Survey and 0.46 +/- 0.05 for Einstein vs. ROSAT pointed) at these longer timescales (similar to 10 yr), thus indicating the possible presence of a long-term component to the variability Whether or not this long-term component is due to the presence of cyclic variability cannot be decided on the basis of existing data. However, assuming that this component is analogous to the observed cyclic variability of the Sun, we find that the relative magnitude of the cyclic component in the ROSAT passband can, at most, be a factor of 4, i.e., I(cyc)/I(min) < 4. This is to be compared with the corresponding but significantly higher solar value of similar to 10-10(2) derived from GOES, Yohkoh, and Solrad data. These results are consistent with the suggestions of earlier studies that a turbulent or distributive dynamo might be responsible for the observed magnetic activity on the most active, rapidly rotating stars. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Kashyap, V (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS-83, Cambridge, MA 02138 USA. EM kashyap@cfa.harvard.edu; jdrake@cfa.harvard.edu NR 54 TC 22 Z9 22 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 20 PY 1999 VL 524 IS 2 BP 988 EP 999 DI 10.1086/307821 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 245YB UT WOS:000083135300039 ER PT J AU Balakrishnan, N Vieira, M Babb, JF Dalgarno, A Forrey, RC Lepp, S AF Balakrishnan, N Vieira, M Babb, JF Dalgarno, A Forrey, RC Lepp, S TI Rate coefficients for ro-vibrational transitions in H-2 due to collisions with He SO ASTROPHYSICAL JOURNAL LA English DT Article DE molecular data; molecular processes ID CROSS-SECTIONS; ENERGY SURFACE; RATE CONSTANTS; RELAXATION; EXCITATION; RECOMBINATION; H-2-MOLECULES; EMISSION; ATOMS AB We present quantum mechanical and quasi-classical trajectory calculations of cross sections for rovibrational transitions in ortho- and para-H-2 induced by collisions with He atoms. Cross sections were obtained for kinetic energies between 10(-4) and 3 eV, and the corresponding rate coefficients were calculated for the temperature range 100 K less than or equal to T less than or equal to 4000 K. Comparisons are made with previous calculations. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. Penn State Univ, Berks Lehigh Valley Coll, Reading, PA 19610 USA. Univ Nevada, Dept Phys, Las Vegas, NV 89154 USA. RP Balakrishnan, N (reprint author), Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, 60 Garden St, Cambridge, MA 02138 USA. OI Babb, James/0000-0002-3883-9501 NR 27 TC 23 Z9 23 U1 0 U2 4 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 OCT 20 PY 1999 VL 524 IS 2 BP 1122 EP 1130 DI 10.1086/307846 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 245YB UT WOS:000083135300049 ER PT J AU Kenyon, SJ Wood, K Whitney, BA Wolff, MJ AF Kenyon, SJ Wood, K Whitney, BA Wolff, MJ TI Forming the dusty ring in HR 4796A SO ASTROPHYSICAL JOURNAL LA English DT Article DE circumstellar matter; planetary systems; solar system : formation; stars : formation; stars : individual (HR 4796A) ID BETA-PICTORIS; GIANT PLANETS; GAS; AGE AB We describe planetesimal accretion calculations for the dusty ring observed in the nearby AO star HR 4796A. Models with initial masses of 10-20 times the minimum-mass solar nebula produce a ring with a width of 7-15 AU and a height of 0.3-0.6 AU at 70 AU in similar to 10 Myr. The ring has a radial optical depth of similar to 1. These results agree with limits derived from infrared images and from the excess infrared luminosity. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Space Sci Inst, Boulder, CO 80303 USA. RP Kenyon, SJ (reprint author), Smithsonian Astrophys Observ, 60 Gareden St, Cambridge, MA 02138 USA. OI Kenyon, Scott/0000-0003-0214-609X NR 25 TC 28 Z9 28 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 OCT 20 PY 1999 VL 524 IS 2 BP L119 EP L123 DI 10.1086/312313 PN 2 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 245YM UT WOS:000083136300011 ER PT J AU Mair, RW Wong, GP Hoffmann, D Hurlimann, MD Patz, S Schwartz, LM Walsworth, RL AF Mair, RW Wong, GP Hoffmann, D Hurlimann, MD Patz, S Schwartz, LM Walsworth, RL TI Probing porous media with gas diffusion NMR SO PHYSICAL REVIEW LETTERS LA English DT Article ID TO-VOLUME RATIO; COEFFICIENT; RELAXATION; FLUIDS; NUCLEI; HE-3 AB We show that gas diffusion nuclear magnetic resonance (GD-NMR) provides a powerful technique for probing the structure of porous media. In random packs of glass beads, using both laser-polarized and thermally polarized xenon gas, we find that GD-NMR can accurately measure the pore space surface-area-to-volume ratio, S/V-p, and the tortuosity, alpha (the latter quantity being directly related to the system's transport properties). We also show that GD-NMR provides a good measure of the tortuosity of sandstone and complex carbonate rocks. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Schlumberger Doll Res Ctr, Ridgefield, CT 06877 USA. Brigham & Womens Hosp, Dept Radiol, Boston, MA 02115 USA. RP Mair, RW (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Patz, Samuel/I-2879-2012 FU FDA HHS [BES-9612237] NR 20 TC 136 Z9 136 U1 5 U2 26 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 OCT 18 PY 1999 VL 83 IS 16 BP 3324 EP 3327 DI 10.1103/PhysRevLett.83.3324 PG 4 WC Physics, Multidisciplinary SC Physics GA 245XH UT WOS:000083133200056 PM 11543587 ER PT J AU Whigham, DF AF Whigham, DF TI Ecological issues related to wetland preservation, restoration, creation and assessment SO SCIENCE OF THE TOTAL ENVIRONMENT LA English DT Article DE wetlands; biodiversity; ecosystem function; 'No Net Loss'; wetland policy; restoration; creation; mitigation; assessment; hydrogeomorphic; HGM; landscape ID VEGETATION; NITRATE; FOREST; RIVERS; PLANT; SOIL AB A wide range of local, state, federal, and private programs are available to support the national (USA) policy of wetland 'No Net Loss'. Implementation of programs, however, has resulted in the continued loss of natural wetlands on the premise that restored or created wetlands will replace the functions and values lost by destruction of natural wetlands. What are the ecological implications and consequences of these programs from a biodiversity and ecosystem perspective? From a biodiversity perspective, ongoing wetland protection policies may not be working because restored or created wetlands are often very different from natural wetlands. Wetland protection policies may also be inadequate to preserve and restore ecological processes such as nutrient cycling because they mostly focus on individual wetlands and ignore the fact that wetlands are integral parts of landscapes. Wetland mitigation projects, for example, often result in the exchange of one type of wetland for another and result in a loss of wetland functions at the landscape level. The most striking weakness in the current national wetlands policy is the lack of protection for 'dry-end' wetlands that are often the focus of debate for what is and what is not a wetland. From an ecological perspective, dry-end wetlands such as isolated seasonal wetlands and riparian wetlands associated with first order streams may be the most important landscape elements. They often support a high biodiversity and they are impacted by human activities more than other types of wetlands. The failings of current wetland protection and mitigation policies are also due, in part, to the lack of ecologically sound wetland assessment methods for guiding decision making processes. The ecologically based Hydrogeomorphic (HGM) approach to wetland assessment has the potential to be an effective tool in managing biodiversity and wetland ecosystem function in support of the national 'No Net Loss' policy. Published by Elsevier Science B.V. C1 Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. RP Whigham, DF (reprint author), Smithsonian Environm Res Ctr, Box 28, Edgewater, MD 21037 USA. EM whigham@serc.si.edu OI Whigham, Dennis/0000-0003-1488-820X NR 66 TC 50 Z9 73 U1 9 U2 80 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0048-9697 J9 SCI TOTAL ENVIRON JI Sci. Total Environ. PD OCT 18 PY 1999 VL 240 IS 1-3 BP 31 EP 40 DI 10.1016/S0048-9697(99)00321-6 PG 10 WC Environmental Sciences SC Environmental Sciences & Ecology GA 243QD UT WOS:000083008000004 ER PT J AU McCarthy, MC Apponi, AJ Gordon, VD Gottlieb, CA Thaddeus, P Crawford, TD Stanton, JF AF McCarthy, MC Apponi, AJ Gordon, VD Gottlieb, CA Thaddeus, P Crawford, TD Stanton, JF TI Rotational spectrum and theoretical structure of the carbene HC4N SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID GAUSSIAN BASIS FUNCTIONS; CARBON-CHAIN MOLECULES; ATOMIC BASIS SETS; FIRST-ROW ATOMS; ANALYTIC EVALUATION; ENERGY GRADIENTS; GAS-PHASE; CONTRACTION; SINGLES; TRIPLE AB Following a high-level coupled cluster calculation, the rotational spectrum of the bent HC4N singlet carbene was detected in a supersonic molecular beam by Fourier transform microwave spectroscopy. The three rotational constants, the leading centrifugal distortion constants, and two nitrogen hyperfine coupling constants were determined to high accuracy. The rotational constants agree with those calculated ab initio to better than 0.5%. Like the isoelectronic C5H2 carbene of similar structure, HC4N was found to have fairly large centrifugal distortion and a large inertial defect. The calculated dipole moment of HC4N is 2.95 D. (C) 1999 American Institute of Physics. [S0021-9606(99)00339-6]. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. Univ Texas, Inst Theoret Chem, Dept Chem, Austin, TX 78712 USA. Univ Texas, Inst Theoret Chem, Dept Biochem, Austin, TX 78712 USA. RP McCarthy, MC (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Crawford, Thomas/A-9271-2017; OI Crawford, Thomas/0000-0002-7961-7016; McCarthy, Michael/0000-0001-9142-0008 NR 29 TC 17 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 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD OCT 15 PY 1999 VL 111 IS 15 BP 6750 EP 6754 DI 10.1063/1.479971 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 244LB UT WOS:000083051600011 ER PT J AU Cox, DP Shelton, RL Maciejewski, W Smith, RK Plewa, T Pawl, A Rozyczka, M AF Cox, DP Shelton, RL Maciejewski, W Smith, RK Plewa, T Pawl, A Rozyczka, M TI Modeling W44 as a supernova remnant in a density gradient with a partially formed dense shell and thermal conduction in the hot interior. I. The analytical model SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : general; ISM : individual (W44); radiative transfer; radio continuum : ISM; supernova remnants ID X-RAY; GALACTIC PLANE; MAGNETIC-FIELDS; PSR B1853+01; RADIO; EMISSION; PULSAR; SHOCK; W28; SUPPRESSION AB We show that many observations of W44, a supernova remnant in the Galactic plane at a distance of about 2500 pc, are remarkably consistent with the simplest realistic model. The model remnant is evolving in a smooth ambient medium of fairly high density, about 6 cm(-3) on average, with a substantial density gradient. At the observed time it has an age of about 20,000 yr, consistent with the age of the associated pulsar, and a radius of 11-13 pc. Over most of the outer surface, radiative cooling has become important in the postshock gas; on the denser end there has been sufficient compression of the cooled gas to develop a very thin dense half-shell of about 450 M., supported against further compression by nonthermal pressure. The half-shell has an expansion velocity of about 150 km s(-1) and is bounded on the outer surface by a radiative shock with that speed. The deep interior of the remnant has a substantial and fairly uniform pressure, as expected from even highly idealized adiabatic models; our model, however, is never adiabatic. Thermal conduction, while the remnant is young and hot, reduces the need for expansion cooling and prevents formation of the intensely vacuous cavity characteristic of adiabatic evolution. It radically alters the interior structure from what tone might expect from familiarity with the Sedov solution. At the time of observation, the temperature in the center is about 6 x 10(6) K, the density about 1 cm(-3). The temperature decreases gradually away from the center, while the density rises. Farther out, where cooling is becoming important, the pressure drops precipitously, and the temperature in the denser gas there is quite low. We provide several analytic tools for the assembly of models of this type. We review the early evolution and shell formation analyses and their generalizations to evolution in a density gradient. We also calculate the density and temperature that should be present in the hot interior of a remnant with thermal conduction. We supply the van der Laan mechanism in a particularly useful form for the calculation of radio continuum from radiative remnants. Finally, we estimate the optical emission that should be present from fluorescence of UV light, emitted by the forming shell and the radiative shock and absorbed in the cold shell and the ambient medium, and the associated 63 mu m [O I] emission. Both are in agreement with the intensity and spatial structures found in recent observations. Neither requires interaction with a dense molecular cloud for its generation. We calculate the gamma rays that should be emitted by cosmic-ray electrons and ions in the shell, interacting with the cold material, and find each capable of generating about 25% of the flux reported by EGRET for the vicinity. C1 Univ Wisconsin, Dept Phys, Madison, WI 53711 USA. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Univ Wisconsin, Dept Astron, Madison, WI 53711 USA. Max Planck Inst Astron, D-69117 Heidelberg, Germany. NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Max Planck Inst Astrophys, D-85740 Garching, Germany. Nicolaus Copernicus Astron Ctr, PL-00716 Warsaw, Poland. RP Univ Wisconsin, Dept Phys, 1150 Univ Ave, Madison, WI 53711 USA. EM cox@wisp.physics.wisc.edu; shelton@pha.jhu.edu; witold@mpia-hd.mpg.de; rsmith@kracko.harvard.edu; tomek@camk.edu.pl; mnr@camk.edu.pl RI Plewa, Tomasz/C-1470-2010 OI Plewa, Tomasz/0000-0002-1762-2565 NR 57 TC 99 Z9 101 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 OCT 10 PY 1999 VL 524 IS 1 BP 179 EP 191 DI 10.1086/307781 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 242TK UT WOS:000082957600016 ER PT J AU Shelton, RL Cox, DP Maciejewski, W Smith, RK Plewa, T Pawl, A Rozyczka, M AF Shelton, RL Cox, DP Maciejewski, W Smith, RK Plewa, T Pawl, A Rozyczka, M TI Modeling W44 as a supernova remnant in a density gradient, with a partially formed dense shell and thermal conduction in the hot interior. II. The hydrodynamic models SO ASTROPHYSICAL JOURNAL LA English DT Article DE hydrodynamics; ISM : individual (W44); ISM : structure; methods : numerical; radio continuum : ISM; supernova remnants ID X-RAY-SPECTRUM; MOLECULAR CLOUDS; EVOLUTION; EMISSION; RADIO; PLASMAS; SHOCK; YOUNG; W28; GAS AB In a previous paper, we presented the analytical background for a new model for W44; in this paper, we report hydrocode experiments verifying many of the details. Our model remnant is evolving in a moderately dense (similar to 6 cm(-3)), ambient medium having a substantial density gradient. At the observed age (similar to 20,000 yr), the shock is radiative over much of the surface, with expansion speeds of only similar to 130-200 km s(-1) for the dense and rare ends, respectively. With these speeds, the remnant has a cool periphery and does not produce a limb-brightened X-ray image. It has thermal conduction within its hot interior, resulting in a nonnegligible density there, and its center is X-ray luminous. The combined effect creates a "center-filled" X-ray image. A thin, very dense cool shell has formed over the denser half of the remnant's surface, and its radio synchrotron emission derives from the highly compressed cosmic rays and swept up magnetic field, producing the usual "shell-type" image associated with radiative remnants. This combination of emission patterns results in the remnant being characterized as having a "thermal composite morphology." Our previous paper demonstrated that the intensities and qualitative distributions of the anticipated optical, IR line, X-ray, radio synchrotron, and gamma-ray emissions from the model are comparable to those actually observed in W44. In this paper we first use a two-dimensional hydrocode to follow the remnant evolution in a density gradient, verifying that the spatial and velocity structure of the H I shell are a good match to the observations, without the complications suggested by Koo & Heiles, and demonstrating that the remnant's asymmetry does not substantially affect the distribution of X-ray emitting material. We also calculate the distribution of radio-continuum emission expected from the compression of the ambient magnetic field and cosmic rays into the dense shell (the van der Laan mechanism) and examine the role of surface crinkling in generating filamentation. The results are in good agreement with observations, though the density of ambient cosmic-ray electrons required to match the observed flux is about 4 times greater than that estimated for the solar neighborhood. A one-dimensional hydrocode model was then used to explore the effects of nonequilibrium ionization on the X-ray spectrum and intensity. Our model is similar to but more comprehensive than the recent one by Harrus et at, and, because their model lacked thermal conduction, ours is more successful in providing the thermal X-rays from the hot interior, including a better match to the spectrum. Neither provides the sharpness of the central peaking of the X-ray distribution without further complications. (For that matter, however, the earlier models with evaporating clouds did no better.) The paper closes with a discussion of the OH masers associated with W44, proposing a specific site for their origin, in the dense trailing edge of the cooling region following the radiative shock. C1 Univ Wisconsin, Dept Phys, Madison, WI 53711 USA. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Max Planck Inst Astron, D-69117 Heidelberg, Germany. NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Max Planck Inst Astrophys, D-85740 Garching, Germany. Nicolaus Copernicus Astron Ctr, PL-00716 Warsaw, Poland. RP Shelton, RL (reprint author), Univ Wisconsin, Dept Phys, 1150 Univ Ave, Madison, WI 53711 USA. RI Plewa, Tomasz/C-1470-2010 OI Plewa, Tomasz/0000-0002-1762-2565 NR 53 TC 67 Z9 68 U1 0 U2 3 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 OCT 10 PY 1999 VL 524 IS 1 BP 192 EP 212 DI 10.1086/307799 PN 1 PG 21 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 242TK UT WOS:000082957600017 ER PT J AU Saar, SH Brandenburg, A AF Saar, SH Brandenburg, A TI Time evolution of the magnetic activity cycle period. II. Results for an expanded stellar sample SO ASTROPHYSICAL JOURNAL LA English DT Review DE novae, cataclysmic variables; stars : activity; stars : late-type; stars : magnetic fields; stars : rotation ID MAIN-SEQUENCE STARS; RS CANUM-VENATICORUM; SUN-LIKE STARS; TERM LUMINOSITY VARIATIONS; SOLAR-TYPE STARS; X-RAY BINARIES; DIFFERENTIAL ROTATION; CATACLYSMIC VARIABLES; CHROMOSPHERIC VARIATIONS; PHOTOMETRIC VARIABILITY AB We further explore nondimensional relationships between the magnetic dynamo cycle period P-eye, the rotational period P-rot, the activity level (as observed in Ca II HK), and other stellar properties by expanding the stellar sample studied in the first paper in this series. We do this by adding photometric and other cycles seen in active stars and the secondaries of CV systems and by selectively adding less certain cycles from the Mount Wilson HK survey; evolved stars, long-term HK trends and secondary P-eye are also considered. We confirm that most stars with age t greater than or similar to 0.1 Gyr occupy two roughly parallel branches, separated by a factor of similar to 6 in P-eye, with the ratio of cycle and rotational frequencies omega(eye)/Omega proportional to Ro(-0.5), where Ro is the Rossby number. Using the model of the first paper in this series, this result implies that the alpha effect increases with mean magnetic field (contrary to the traditional alpha-quenching concept) and that alpha and omega(eye) decrease with t. Stars are not strictly segregated onto one or the other branch by activity level, though the high-omega(eye)/Omega branch is primarily composed of inactive stars. The expanded data set suggests that for t greater than or similar to 1 Gyr, stars can have cycles on one or both branches, though among older stars, those with higher (lower) mass tend to have their primary P-eye on the lower (upper) omega(eye)/Omega branch. The Sun's similar to 80 yr Gleissberg cycle agrees with this scenario, suggesting that longterm activity "trends" in many stars may be segments of long (P-eye similar to 50-100 yr) cycles not yet resolved by the data. Most very active stars (P-rot < 3 days) appear to occupy a new, third branch with omega(eye)/Omega proportional to Ro(0.4). Many RS CVn variables lie in a transition region between the two most active branches. We compare our results with various models, discuss their implications for dynamo theory and evolution, and use them to predict P-eye for three groups: stars with long-term HK trends, stars in young open clusters, and stars that may be in Maunder-like magnetic minima. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Newcastle Univ, Dept Math, Newcastle Upon Tyne NE1 7RU, Tyne & Wear, England. RP Harvard Smithsonian Ctr Astrophys, MS-58,60 Garden St, Cambridge, MA 02138 USA. EM saar@cfa.harvard.edu; Axel.Brandenburg@newcastle.ac.uk RI Brandenburg, Axel/I-6668-2013 OI Brandenburg, Axel/0000-0002-7304-021X NR 129 TC 167 Z9 167 U1 0 U2 2 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 OCT 10 PY 1999 VL 524 IS 1 BP 295 EP 310 DI 10.1086/307794 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 242TK UT WOS:000082957600024 ER PT J AU Evans, NR Carpenter, K Robinson, R Massa, D Wahlgren, GM Vinko, J Szabados, L AF Evans, NR Carpenter, K Robinson, R Massa, D Wahlgren, GM Vinko, J Szabados, L TI Toward an orbit for the high-luminosity cepheid T monocerotis SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : spectroscopic; Cepheids; stars : chemically peculiar stars : fundamental parameters; stars : individual (T Monocerotis) ultraviolet : stars ID EFFECTIVE TEMPERATURES; BOLOMETRIC CORRECTIONS; CLASSICAL CEPHEIDS; NORTHERN CEPHEIDS; RADIAL-VELOCITIES; BRIGHT CEPHEIDS; METALLIC-LINE; NORMAL STARS; AP STARS; AM STARS AB We have obtained new velocities of the long-period Cepheid T Mon from the ground and velocities of its hot companion with the Hubble Space Telescope (HST) and the International Ultraviolet Explorer (IUE). Although observations do not cover a full orbit, both the maximum and minimum orbital velocities have now been obtained. We present a preliminary orbit and discuss the uncertainties in the orbital parameters. The velocities for the companion appear to be inconsistent with binary orbital motion, and it is likely that the companion is itself a binary in a short-period orbit. The HST spectrum of the companion shows that it is a chemically peculiar star, probably magnetic. Because it is coupled with the more massive Cepheid, it must be very close to the zero-age main sequence. The well-determined mass function from the preliminary orbit implies that the inclination of the long-period system is close to 90 degrees. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Comp Sci Corp, Astron Programs, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Raytheon STX Corp, Greenbelt, MD 20771 USA. Univ Lund, Dept Phys, S-22362 Lund, Sweden. JATE Univ, Dept Opt, H-6720 Szeged, Hungary. Konkoly Observ Budapest, H-1525 Budapest, Hungary. RP Evans, NR (reprint author), Smithsonian Astrophys Observ, 60 Garden St,Ms 4, Cambridge, MA 02138 USA. RI Carpenter, Kenneth/D-4740-2012; OI Vinko, Jozsef/0000-0001-8764-7832 NR 76 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 OCT 10 PY 1999 VL 524 IS 1 BP 379 EP 393 DI 10.1086/307810 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 242TK UT WOS:000082957600029 ER PT J AU Jiggins, CD Beltran, M AF Jiggins, CD Beltran, M TI Conserved ecological niches SO SCIENCE LA English DT Letter C1 UCL, Dept Biol, Galton Lab, London NW1 2HE, England. Smithsonian Trop Res Inst, Balboa, Panama. RP Jiggins, CD (reprint author), UCL, Dept Biol, Galton Lab, London NW1 2HE, England. EM jigginsc@gamboa.si.edu RI Jiggins, Chris/B-9960-2008 OI Jiggins, Chris/0000-0002-7809-062X NR 2 TC 0 Z9 0 U1 0 U2 1 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 OCT 8 PY 1999 VL 286 IS 5438 BP 240 EP 241 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 243YE UT WOS:000083024400022 ER PT J AU Timmermans, E Tommasini, P Cote, R Hussein, MS Kerman, A AF Timmermans, E Tommasini, P Cote, R Hussein, MS Kerman, A TI Rarified liquid properties of hybrid atomic-molecular Bose-Einstein condensates SO PHYSICAL REVIEW LETTERS LA English DT Article ID ATTRACTIVE INTERACTIONS; FESHBACH RESONANCES; COLLISIONS; SCATTERING; FIELDS; GASES AB In the atomic Bose-Einstein condensate, the interactions that bring a binary atom system to an intermediate state molecule in the Feshbach resonance create a second condensate component of molecules. The atomic and molecular condensates coherently exchange pairs of atoms. We discuss a signature of the coherent intercondensate exchange: Josephson-like oscillations of the atomic and molecular populations in response to a sudden change of the energy detuning. The dependence of the many-body ground state energy on volume suggests that the on-resonant ground state is a dilute condensate with the liquidlike property of a self-determined density. C1 Harvard Smithsonian Ctr Astrophys, Inst Atom & Mol Phys, Cambridge, MA 02138 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Sao Paulo, Inst Fis, BR-05315970 Sao Paulo, Brazil. MIT, Ctr Theoret Phys, Nucl Sci Lab, Cambridge, MA 02139 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. RP Timmermans, E (reprint author), Harvard Smithsonian Ctr Astrophys, Inst Atom & Mol Phys, 60 Garden St, Cambridge, MA 02138 USA. NR 31 TC 121 Z9 122 U1 1 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 4 PY 1999 VL 83 IS 14 BP 2691 EP 2694 DI 10.1103/PhysRevLett.83.2691 PG 4 WC Physics, Multidisciplinary SC Physics GA 241PV UT WOS:000082892500002 ER PT J AU Sakai, S Momose, K Yumoto, T Nagamitsu, T Nagamasu, H Hamid, AA Nakashizuka, T AF Sakai, S Momose, K Yumoto, T Nagamitsu, T Nagamasu, H Hamid, AA Nakashizuka, T TI Plant reproductive phenology over four years including an episode of general flowering in a lowland dipterocarp forest, Sarawak, Malaysia SO AMERICAN JOURNAL OF BOTANY LA English DT Article DE borneo; dipterocarp forest; flowering trigger; general flowering; Malaysia; predator satiation; promotion of pollination ID TROPICAL RAIN-FOREST; COSTA-RICA; CHARACTER DISPLACEMENT; BEETLE POLLINATION; ASEASONAL TROPICS; SEED PREDATORS; TREE PHENOLOGY; DRY FOREST; COMPETITION; PATTERNS AB The first systematic observation of a general flowering, a phenomenon unique to lowland mixed-dipterocarp forests in Southeast Asia, is presented. During general flowering, which occurs at irregular intervals of 3-10 yr, nearly all dipterocarp species together with species of other families come heavily into Bower. We monitored reproductive phenology of 576 individual plants representing 305 species in 56 families in Sarawak, Malaysia. Observations continued for 53 mo from August 1992 and covered one episode of a general flowering cycle. Among 527 effective reproductive events during 43 mo, 57% were concentrated in the general flowering period (GFP) of 10 mo in 1996. We classified 257 species into flowering types based on timing and frequency of flowering, The most abundant type was "general flowering" (35%), which flowered only during GFP. The others were '"supra-annual" (19%), "annual" (13%), and "sub-annual" (5%) types. General flowering type and temporal aggregation in reproductive events were commonly found among species in various categories of taxonomic groups, life forms, pollination systems, and fruit types. Possible causes for general flowering, such as promotion of pollination brought about by interspecific synchronization and paucity of climatic cues suitable for flowering trigger, are proposed, in addition to the predator satiation hypothesis of Janzen (1974). C1 Kyoto Univ, Ctr Ecol Res, Otsu, Shiga 5202113, Japan. Kyoto Univ, Grad Sch Asian & African Area Studies, Kyoto 6068501, Japan. Forestry & Forest Prod Res Inst, Sapporo, Hokkaido 0628516, Japan. Kyoto Univ, Kyoto Univ Museum, Kyoto 6068501, Japan. Forest Res Ctr, Forest Dept Sarawak, Sarawak, Malaysia. Japan Sci & Technol Corp, CREST, Kawaguchi 3320012, Japan. RP Sakai, S (reprint author), Smithsonian Trop Res Inst, U0948, Apartado 2072, Balboa Ancon, Panama. RI Yumoto, Takakazu/B-6215-2013; Nagamitsu, Teruyoshi/J-7710-2015 OI Nagamitsu, Teruyoshi/0000-0003-3366-7197 NR 87 TC 135 Z9 144 U1 3 U2 47 PU BOTANICAL SOC AMER INC PI COLUMBUS PA OHIO STATE UNIV-DEPT BOTANY 1735 NEIL AVE, COLUMBUS, OH 43210 USA SN 0002-9122 J9 AM J BOT JI Am. J. Bot. PD OCT PY 1999 VL 86 IS 10 BP 1414 EP 1436 DI 10.2307/2656924 PG 23 WC Plant Sciences SC Plant Sciences GA 248BE UT WOS:000083254800007 PM 10523283 ER PT J AU Wilczynski, W Rand, AS Ryan, MJ AF Wilczynski, W Rand, AS Ryan, MJ TI Female preferences for temporal order of call components in the tungara frog: a Bayesian analysis SO ANIMAL BEHAVIOUR LA English DT Article ID TREEFROG HYLA-CINEREA; SEXUAL SELECTION; PHYSALAEMUS-PUSTULOSUS; MATING PREFERENCES; HYPEROLIUS-MARMORATUS; SENSORY EXPLOITATION; ACOUSTIC CRITERIA; MASKING PATTERNS; AUDITORY-NERVE; MATE CHOICE AB We employed a Bayesian statistical approach to examine female preferences in the Neotropical frog Physalaemus pustulosus for the temporal relationship of the two parts of the conspecific advertisement call. The male advertisement call consists of a 'whine', which is necessary for species recognition, followed immediately by one or more 'chucks', which make the whine more attractive to females. We conducted 42 two-choice experiments with a total of 840 individual tests to compare the attractiveness of a whine with a chuck in a variety of positions relative to the start of the whine against a normal whine or against a normal whine/chuck. Females have a bimodal preference function for chuck position. Chucks placed in a variety of positions after the whine(including the position of a chuck in a normal call) were generally as attractive as a normal whine/chuck. Chucks placed before the whine were generally more attractive than a whine alone, and in some positions as attractive as the normal whine/chuck. Chucks overlapping the end of the whine make the call more attractive than a whine alone, but not as attractive as a normal whine/chuck, while chucks overlapping an initial portion of the whine beginning 50 ms into it are ignored; previous work (Wilczynski et al. 1995, Animal Behaviour, 49, 911-929) indicates this region to be critical for species recognition. These results suggest that female P. pustulosus have preferences for the temporal relationship of the two parts of the conspecific male advertisement call that far exceed the vocal signals produced by males, and that male calls have evolved calls to exploit one peak of this function. (C) 1999 The Association for the Study of Animal Behaviour. C1 Univ Texas, Dept Psychol, Austin, TX 78712 USA. Univ Texas, Dept Zool, Austin, TX 78712 USA. Smithsonian Trop Res Inst, Balboa, Panama. RP Wilczynski, W (reprint author), Univ Texas, Dept Psychol, 330 Mezes Hall, Austin, TX 78712 USA. EM wilczynski@psy.utexas.edu NR 51 TC 27 Z9 29 U1 0 U2 2 PU ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0003-3472 J9 ANIM BEHAV JI Anim. Behav. PD OCT PY 1999 VL 58 BP 841 EP 851 DI 10.1006/anbe.1999.1208 PN 4 PG 11 WC Behavioral Sciences; Zoology SC Behavioral Sciences; Zoology GA 249TA UT WOS:000083347600017 ER PT J AU Porro, IL Traub, WA Carleton, NP AF Porro, IL Traub, WA Carleton, NP TI Effect of telescope alignment on a stellar interferometer SO APPLIED OPTICS LA English DT Article ID IOTA INTERFEROMETER AB For a ground-based stellar interferometer, we investigate the effect of wave-front distortions that are due to telescope alignment errors and other factors. We apply the results to the IR/Optical Telescope Array (IOTA) interferometer. We present the computational method used in our simulation program to calculate explicitly the wave-front shape from an arbitrarily misaligned telescope. We calculate the wave-front shape and variance for a suite of misalignment conditions and interpret these results to find allowable tolerances on the positions and tilts of the telescope mirrors. We calculate the expected Strehl ratios from a total often types of factor, including telescope alignment, that are expected to be important in a real interferometer. Ranking the expected wave-front perturbations, we find that three of them, the wave-front curvature from atmospheric turbulence, the servo system time constant, and the flatness of the relay optics surfaces, are more significant than the telescope alignment factor. We compare observational experience at IOTA with our model estimate of the overall Strehl ratio in the visual and the infrared, finding moderately good agreement and, more important, a guide for future instrumental improvements. (C) 1999 Optical Society of America. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Porro, IL (reprint author), Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany. EM porro@mpia-hd.mpg.de NR 17 TC 12 Z9 12 U1 1 U2 1 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 OCT 1 PY 1999 VL 38 IS 28 BP 6055 EP 6067 DI 10.1364/AO.38.006055 PG 13 WC Optics SC Optics GA 244YV UT WOS:000083079100022 PM 18324129 ER PT J AU Panzer, M AF Panzer, M TI What price history? To establish a market value for the Zapruder film of the JFK assassination SO ART IN AMERICA LA English DT Article C1 Smithsonian Inst, Washington, DC 20560 USA. RP Panzer, M (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU BRANT PUBL, INC PI NEW YORK PA 575 BROADWAY, NEW YORK, NY 10012 USA SN 0004-3214 J9 ART AM JI Art Am. PD OCT PY 1999 VL 87 IS 10 BP 67 EP + PG 0 WC Art SC Art GA 238AB UT WOS:000082687800017 ER PT J AU Kirwin, L AF Kirwin, L TI East side story (New-York's East Village art scene of the 1980s) SO ARTFORUM LA English DT Article C1 Smithsonian Inst, Arch Amer Art, Washington, DC 20560 USA. RP Kirwin, L (reprint author), Smithsonian Inst, Arch Amer Art, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ARTFORUM PI NEW YORK PA 65 BLECKER ST ATTN: SUBSCRIPTIONS, NEW YORK, NY 10012 USA SN 0004-3532 J9 ARTFORUM JI Artforum PD OCT PY 1999 VL 38 IS 2 BP 120 EP + PG 0 WC Art SC Art GA 241TF UT WOS:000082898100019 ER PT J AU Kirwin, L AF Kirwin, L TI The East Village 1979-1989 - A chronology SO ARTFORUM LA English DT Editorial Material C1 Smithsonian Inst, Arch Amer Art, Washington, DC 20560 USA. RP Kirwin, L (reprint author), Smithsonian Inst, Arch Amer Art, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ARTFORUM PI NEW YORK PA 65 BLECKER ST ATTN: SUBSCRIPTIONS, NEW YORK, NY 10012 USA SN 0004-3532 J9 ARTFORUM JI Artforum PD OCT PY 1999 VL 38 IS 2 BP 121 EP 128 PG 8 WC Art SC Art GA 241TF UT WOS:000082898100020 ER PT J AU Kirwin, L AF Kirwin, L TI EV in the press (Remembering the East Village art scene of the 1980s) SO ARTFORUM LA English DT Article C1 Smithsonian Inst, Arch Amer Art, Washington, DC 20560 USA. RP Kirwin, L (reprint author), Smithsonian Inst, Arch Amer Art, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ARTFORUM PI NEW YORK PA 65 BLECKER ST ATTN: SUBSCRIPTIONS, NEW YORK, NY 10012 USA SN 0004-3532 J9 ARTFORUM JI Artforum PD OCT PY 1999 VL 38 IS 2 BP 127 EP + PG 0 WC Art SC Art GA 241TF UT WOS:000082898100028 ER PT J AU Barth, AJ Tran, HD Brotherton, MS Filippenko, AV Ho, LC van Breugel, W Antonucci, R Goodrich, RW AF Barth, AJ Tran, HD Brotherton, MS Filippenko, AV Ho, LC van Breugel, W Antonucci, R Goodrich, RW TI Polarized narrow-line emission from the nucleus of NGC 4258 SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : individual NGC 4258); galaxies : nuclei; galaxies : Seyfert; polarization ID SEYFERT 2 GALAXIES; ACTIVE GALACTIC NUCLEI; EXCITATION MECHANISM; MOLECULAR DISK; NGC-4258; SEARCH; DISCOVERY; NGC-1068; SPECTRUM; PROFILES AB The detection of polarized continuum and line emission from the nucleus of NGC 4258 by Wilkes et al. in 1995 provides an intriguing application of the unified model of Seyfert nuclei to a galaxy in which there is known to be an edge-on, rotating disk of molecular gas surrounding the nucleus. Unlike most Seyfert nuclei, however, NGC 4258 has strongly polarized narrow emission lines. To further investigate the origin of the polarized emission, we have obtained spectropolarimetric observations of the NGC 4258 nucleus at the Keck II telescope. The narrow-line polarizations range from 1.0% for [S II] lambda 6716 to 13.9% for the [O II] lambda lambda 7319, 7331 blend, and the position angle of polarization is oriented nearly parallel to the projected plane of the masing disk. A correlation between critical density and degree of polarization is detected for the forbidden lines, indicating that the polarized emission arises from relatively dense (n(e) greater than or similar to 10(4) cm(-3)), radially stratified gas. An archival Hubble Space Telescope narrowband [O III] image shows that the narrow-line region has a compact, nearly unresolved core, implying a FWHM size of less than or similar to 2.5 pc. We discuss the possibility that the polarized emission might arise from the accretion disk itself and become polarized by scattering within the disk atmosphere. A more likely scenario is an obscuring torus or strongly warped disk surrounding the inner portion of a narrow-line region that is strongly stratified in density. The compact size of the narrow-line region implies that the obscuring structure must be smaller than about 2.5 pc in diameter. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Observ Carnegie Inst Washington, Pasadena, CA 91101 USA. Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. WM Keck Observ, Kamuela, HI 96743 USA. RP Barth, AJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 49 TC 16 Z9 16 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 EI 1538-3881 J9 ASTRON J JI Astron. J. PD OCT PY 1999 VL 118 IS 4 BP 1609 EP 1617 DI 10.1086/301055 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 251CR UT WOS:000083427500012 ER PT J AU Hartmann, L Calvet, N Allen, L Chen, H Jayawardhana, R AF Hartmann, L Calvet, N Allen, L Chen, H Jayawardhana, R TI The complex protostellar source IRAS 04325+2402 SO ASTRONOMICAL JOURNAL LA English DT Article DE circumstellar matter; stars : formation; stars : pre-main-sequence ID AURIGA MOLECULAR CLOUD; EMBEDDED YOUNG STARS; T-TAURI STARS; GG TAURI; COLLAPSE; MODELS; IMAGES; PROTOSTARS; OBJECTS; CORES AB We report Hubble Space Telescope near-infrared NICMOS observations of a remarkable low-luminosity Class I (protostellar) source in the Taurus Molecular Cloud. IRAS 04325+2402 exhibits a complex bipolar scattered light nebula. The central continuum source is resolved and may be multiple, or it may be crossed by a small dust lane. Complex arcs seen in scattered light surround the central source; the physical nature of these structures is not clear, but they may reflect perturbations from multiple stellar sources or from time-dependent mass ejection. A second, resolved continuum source is found at a projected distance of approximately 1150 AU from the central region, near the edge of a nebular lobe probably produced by outflow. The images indicate that this second source is another low-luminosity young stellar object, seen nearly edge-on through a dusty disk and envelope system with disk diameter of about 60 AU. We suggest that the scattered light "streaks" associated with this second source are limb-brightened outflow cavities in the dusty envelope, possibly perturbed by interaction with the outflow lobes of the main source. The nature of the companion is uncertain, since it is observed mostly in scattered light. But it is most probably a very low mass star or brown dwarf, with a minimum luminosity of approximately 10(-2) L-.. Our results show that protostellar sources may have multiple centers of infall and nonaligned disks and outflows, even on relatively small scales. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Ctr Invest Astron, Merida, Venezuela. RP Hartmann, L (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,Mail Stop 42, Cambridge, MA 02138 USA. NR 34 TC 25 Z9 25 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 OCT PY 1999 VL 118 IS 4 BP 1784 EP 1790 DI 10.1086/301040 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 251CR UT WOS:000083427500027 ER PT J AU Terndrup, DM Krishnamurthi, A Pinsonneault, MH Stauffer, JR AF Terndrup, DM Krishnamurthi, A Pinsonneault, MH Stauffer, JR TI A search for photometric rotation periods in low-mass stars and brown dwarfs in the Pleiades SO ASTRONOMICAL JOURNAL LA English DT Article DE open clusters and associations : individual (Pleiades); stars : activity; stars : low-mass, brown dwarfs; stars : rotation ID SOLAR-TYPE STARS; TIME-SERIES ANALYSIS; ALPHA-PERSEI; CHROMOSPHERIC ACTIVITY; LITHIUM DEPLETION; MAIN-SEQUENCE; EVOLUTION; CLUSTER; VELOCITIES; FIELD AB We have photometrically monitored (Cousins I-c) eight low-mass stars and brown dwarfs that are probable members of the Pleiades. We derived rotation periods for two of the stars-HHJ 409 and CFHT-PL 8-to be 0.258 and 0.401 days, respectively. The masses of these stars ate near 0.4 and 0.08 M-., respectively; the latter is the second such object near the hydrogen-burning boundary for which a rotation period has been measured. We also observed HHJ 409 in V. The relative amplitude in the two bands shows that the spots in that star are about 200 K cooler than the stellar effective temperature of 3560 K and have a filling factor on the order of 13%. With one possible exception, the remaining stars in the sample do not show photometric variations larger than the mean error of measurement. We also examined the M9.5 V disk star 2MASS J0149090 + 295613, which had previously exhibited a strong flare event, but we did not detect any photometric variation. C1 Ohio State Univ, Dept Astron, Columbus, OH 43210 USA. Natl Inst Stand & Technol, Boulder, CO 80309 USA. Univ Colorado, JILA, Boulder, CO 80309 USA. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Terndrup, DM (reprint author), Ohio State Univ, Dept Astron, 174 W 18Th Ave, Columbus, OH 43210 USA. NR 41 TC 45 Z9 45 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 OCT PY 1999 VL 118 IS 4 BP 1814 EP 1818 DI 10.1086/301061 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 251CR UT WOS:000083427500031 ER PT J AU Torres, G Lacy, CHS Claret, A Zakirov, MM Arzumanyants, GC Bayramov, N Hojaev, AS Stefanik, RP Latham, DW Sabby, JA AF Torres, G Lacy, CHS Claret, A Zakirov, MM Arzumanyants, GC Bayramov, N Hojaev, AS Stefanik, RP Latham, DW Sabby, JA TI Absolute dimensions of the A-type eclipsing binary V364 Lacertae SO ASTRONOMICAL JOURNAL LA English DT Article DE binaries : eclipsing; binaries : spectroscopic; stars : evolution; stars : fundamental parameters; stars : individual (V364 Lacertae) ID APSIDAL MOTION TEST; SPECTROSCOPIC BINARIES; RADIAL-VELOCITIES; STELLAR STRUCTURE; MAIN-SEQUENCE; STARS; SYNCHRONIZATION; SYSTEMS; OPACITIES; EVOLUTION AB We present photoelectric observations in B and V, as well as spectroscopic observations of the 7.3 day period double-lined eclipsing binary V364 Lacertae. From the analysis of the light curves and the radial velocity curves we have determined the absolute dimensions of the components with high precision (less than or similar to 1%). The masses for the primary and secondary are M-A = 2.333 +/- 0.015 M-. and M-B = 2.296 +/- 0.025 M-., respectively, and the radii are R-A = 3.307 +/- 0.038 R-. and R-B = 2.985 +/- 0.035 R-.. We derive also effective temperatures of T-eff(A) = 8250 +/- 150 K and T-eff(B) = 8500 +/- 150 K, and projected rotational velocities of v(A) sin i = 45 +/- 1 km s(-1) and v(B) sin i = 15 +/- 1 km s(-1). Evolutionary tracks from current stellar evolution models are in good agreement with the observations for a system age of log t = 8.792 (6.2 x 10(8) yr) and for solar metallicity. Hints of a lower metallicity from spectroscopy and photometry appear to be ruled out by these models, but a definitive comparison must await a more accurate spectroscopic abundance determination. Analysis of all available eclipse timings along with our radial velocities of this moderately eccentric system (e = 0.2873 +/- 0.0014) has revealed a small but significant motion of the line of apsides of (omega) over dot = 0.00258 +/- 0.00033 deg cycle(-1), corresponding to an apsidal period of U = 2810 +/- 360 yr. The contribution from general relativity effects is significant (similar to 17%). A comparison with predictions from interior structure models shows the real stars to be less concentrated in mass than expected. Our measurements of the projected rotational velocities indicate that the primary star is essentially pseudosynchronized (synchronized at periastron), while the secondary is spinning 3 times more slowly and is not yet synchronized. Both the rotational status of the stars and the nonzero eccentricity of the orbit are consistent with the predictions from tidal theory, specifically for the radiative damping mechanism. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Arkansas, Dept Phys, Fayetteville, AR 72701 USA. CSIC, Inst Astrofis Andalucia, E-18080 Granada, Spain. Astron Inst, High Altitude Maidanak Observ, Tashkent 700052, Uzbekistan. RP Torres, G (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 54 TC 19 Z9 19 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 OCT PY 1999 VL 118 IS 4 BP 1831 EP 1844 DI 10.1086/301050 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 251CR UT WOS:000083427500033 ER PT J AU Forster, K Leighly, KM Kay, LE AF Forster, K Leighly, KM Kay, LE TI The X-ray spectra and spectral variability of intermediate-type Seyfert galaxies: ASCA observations of NGC 4388 and ESO 103-G35 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : Seyfert; quasars : individual (NGC 4388; ESO 103-G35); X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; VIRGO CLUSTER; COLD MATTER; 2 GALAXIES; EMISSION; ABSORPTION; NGC-4388; REFLECTION; LINE; SPECTROSCOPY AB The X-ray spectra of two intermediate-type Seyfert galaxies are investigated using ASCA observations separated by more than 1 yr. Both NGC 4388 and ESO 103-G35 exhibit strong, narrow Fe K alpha line emission and absorption by cold neutral gas with a column density similar to 10(23) cm(-2), characteristic of the X-ray spectra of type 2 Seyfert galaxies. The power-law continuum flux has changed by a factor of 2 over a timescale of similar to 2 yr for both objects, declining in the case of NGC 4388 and rising in ESO 103-G35. No variation was observed in the equivalent width of the Fe K alpha line in the spectra of NGC 4388, implying that the line flux declined with the continuum. We find that the strength of the line cannot be accounted for by fluorescence in line-of-sight material with the measured column density unless a "leaky-absorber" model of the type favored for IRAS 04575-7537 is employed. The equivalent width of the Fe K alpha emission line is seen to decrease between the observations of ESO 103-G35 while the continuum flux increased. The 1996 observation of ESO 103-G35 can also be fitted with an absorption edge at 7.4 +/- 0.2 keV due to partially ionized iron, and when an ionized absorber model is fitted to the data it is found that the equivalent column of neutral hydrogen rises to 3.5 x 10(23) cm(-2). The Fe K alpha line flux can be accounted by fluorescence in this material alone, and this model is also a good representation of the 1988 and 1991 Ginga observations. There is then no requirement for a reflection component in the ASCA spectra of ESO 103-G35 or NGC 4388. C1 Columbia Univ, Dept Astron, New York, NY 10027 USA. Columbia Univ Barnard Coll, Dept Phys & Astron, New York, NY 10027 USA. RP Forster, K (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM kforster@head-cfa.harvard.edu NR 84 TC 15 Z9 15 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 1 PY 1999 VL 523 IS 2 BP 521 EP 539 DI 10.1086/307761 PN 1 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239MG UT WOS:000082771500005 ER PT J AU Sakai, S Ferrarese, L Kennicutt, RC Grahm, JA Silbermann, NA Mould, JR Freedman, WL Bresolin, F Ford, HC Gibson, BK Han, MS Harding, P Hoessel, JG Huchra, JP Hughes, SM Illingworth, GD Kelson, D Macri, L Madore, BF Phelps, RL Saha, A Sebo, KM Setson, PB Turner, A AF Sakai, S Ferrarese, L Kennicutt, RC Grahm, JA Silbermann, NA Mould, JR Freedman, WL Bresolin, F Ford, HC Gibson, BK Han, MS Harding, P Hoessel, JG Huchra, JP Hughes, SM Illingworth, GD Kelson, D Macri, L Madore, BF Phelps, RL Saha, A Sebo, KM Setson, PB Turner, A TI The Hubble Space Telescope Extragalactic Distance Scale Key Project. XXIII. The discovery of Cepheids in NGC 3319 SO ASTROPHYSICAL JOURNAL LA English DT Article DE Cepheids; galaxies : distances and redshifts; galaxies : individual (NGC 3319) ID SPIRAL GALAXIES; EXTINCTION; PHOTOMETRY; STARS AB The distance to NGC 3319 has been determined from Cepheid variable stars as part of the Hubble Space Telescope Key Project on the Extragalactic Distance Scale. Thirteen and four epochs of observations, using filters F555W (V) and F814W (I), respectively, were made with the Wide Field Planetary Camera 2. Thirty-three Cepheid variables between periods of 8 and 47 days were discovered. Adopting a Large Magellanic Cloud distance modulus of 18.50 +/- 0.10 mag and extinction of E(V-I) = 0.13 mag, a true reddening-corrected distance modulus (based on an analysis employing the ALLFRAME software package) of 30.78 +/- 0.14 (random) +/-0.10 (systematic) mag and the extinction of EV-I) = 0.06 mag were determined for NGC 3319. This galaxy is the last galaxy observed for the HST H-o Key Project. C1 Kitt Peak Natl Observ, Natl Opt Astron Observ, Tucson, AZ 85726 USA. CALTECH, Jet Prop Lab, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Carnegie Inst Washington, Dept Terr Magnetism, Washington, DC 20015 USA. Australian Natl Univ, Mt Stromlo & Siding Spring Observ, Weston Creek, ACT 2611, Australia. Carnegie Inst Washington Observ, Pasadena, CA 91101 USA. European So Observ, D-85748 Garching, Germany. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Colorado, Dept Astrophys & Planetary Sci, Ctr Astrophys & Space Astron, Boulder, CO 80309 USA. Avanti Corp, Fremont, CA 94538 USA. Univ Wisconsin, Dept Astron, Madison, WI 53706 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. Univ Calif Santa Cruz, Lick Observ, Santa Cruz, CA 95064 USA. Natl Res Council Canada, Herzberg Inst Astrophys, Dominion Astrophys Observ, Victoria, BC V8X 4M6, Canada. RP Sakai, S (reprint author), Kitt Peak Natl Observ, Natl Opt Astron Observ, POB 26732, Tucson, AZ 85726 USA. RI Gibson, Brad/M-3592-2015; OI Gibson, Brad/0000-0003-4446-3130; Macri, Lucas/0000-0002-1775-4859 NR 28 TC 22 Z9 22 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 OCT 1 PY 1999 VL 523 IS 2 BP 540 EP 558 DI 10.1086/307776 PN 1 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239MG UT WOS:000082771500006 ER PT J AU Sparks, WB Macchetto, F Panagia, N Boffi, FR Branch, D Hazen, ML Della Valle, M AF Sparks, WB Macchetto, F Panagia, N Boffi, FR Branch, D Hazen, ML Della Valle, M TI Evolution of the light echo of SN 1991T SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : individual (NGC 4527); galaxies : photometry; supernovae : individual (SN 1991T) ID CALIBRATION AB Schmidt et al. presented strong evidence (photometry and spectroscopy) that the late time optical emission of SN 1991T in the Virgo spiral NGC 4527 is caused by a light echo. Here, we present photometry with the Wide Field and Planetary Camera 2 and high-resolution imaging polarimetry and photometry with the Faint Object Camera on board the Hubble Space Telescope, which demonstrates that the feature is indeed a light echo of the original supernova. We show that the emission is spatially resolved, complex, and both growing in size and changing in morphology. The echo is slowly fading. Our primary interest is to use the echo for estimating the distance to the host galaxy geometrically (see 1994 work by Sparks). Given that the elapsed time since the supernova exploded is small and that the galaxy is relatively distant, the expected region of maximally polarized emission cannot be fully resolved as yet. However, we do find polarized emission at the center of the echo, and simple models may be used to yield a distance estimate. The models favor smaller distances, with approximate to 15 Mpc being the upper allowable distance, subject to caveats described in the text. The echo is consistent with being caused by a dust cloud of uniform density n similar to 0.9 cm(-3) and extending to approximate to 50 pc in front of the supernova. It is encouraging that even in a case very far from ideal, we can use this type of observation to derive a distance. C1 Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Oklahoma, Dept Phys & Astron, Norman, OK 73019 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Padua, Dipartimento Astron, I-35122 Padua, Italy. European Space Agcy, ESTEC, Div Astrophys, NL-2200 AG Noordwijk, Netherlands. RP Sparks, WB (reprint author), Johns Hopkins Univ, Baltimore, MD 21218 USA. NR 23 TC 40 Z9 41 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 OCT 1 PY 1999 VL 523 IS 2 BP 585 EP 592 DI 10.1086/307766 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239MG UT WOS:000082771500010 ER PT J AU Falco, EE Impey, CD Kochanek, CS Lehar, J McLeod, BA Rix, HW Keeton, CR Munoz, JA Peng, CY AF Falco, EE Impey, CD Kochanek, CS Lehar, J McLeod, BA Rix, HW Keeton, CR Munoz, JA Peng, CY TI Dust and extinction curves in galaxies with z > 0: The interstellar medium of gravitational lens galaxies SO ASTROPHYSICAL JOURNAL LA English DT Review DE dust, extinction; galaxies : ISM; galaxies : photometry; gravitational lensing ID SPACE-TELESCOPE OBSERVATIONS; REDSHIFTED MOLECULAR ABSORPTION; LINE QSO H1413+1143; EINSTEIN RING; ENERGY-DISTRIBUTIONS; ELLIPTIC GALAXIES; PKS 1830-211; LY-ALPHA; SYSTEM; QUASAR AB We determine 37 differential extinctions in 23 gravitational lens galaxies over the range 0 less than or similar to z(l) less than or similar to 1. Only seven of the 23 systems have spectral differences consistent with no differential extinction. The median differential extinction for the optically selected (radio-selected) subsample is Delta E(B-V)= 0.04 (0.06) mag. The extinction is patchy and shows no correlation with impact parameter. The median total extinction of the bluest images is E(B - V) = 0.08 mag, although the total extinction distribution is dominated by the uncertainties in the intrinsic colors of quasars. The directly measured extinction distributions are consistent with the mean extinction estimated by comparing the statistics of quasar and radio lens surveys, thereby confirming the need for extinction corrections when using the statistics of lensed quasars to estimate the cosmological model. A disjoint subsample of two face-on, radio-selected spiral lenses shows both high differential and total extinctions, but standard dust-to-gas ratios combined with the observed molecular gas column densities overpredict the amount of extinction by factors of 2-5. For several systems we can estimate the extinction law, ranging from R(v) = 1.5 +/- 0.2 for a z(l) = 0.96 elliptical, to R(v) = 7.2 +/- 0.1 for a z(l) = 0.68 spiral. For the four radio lenses where we can construct nonparametric extinction curves, we find no evidence for gray dust over the IR-UV wavelength range. The dust can be used to estimate lens redshifts with reasonable accuracy, although we sometimes find two degenerate redshift solutions. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. RP Falco, EE (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM efalco@cfa.harvard.edu; impey@as.arizona.edu; ckochanek@cfa.harvard.edu; jlehar@cfa.harvard.edu; bmcleod@cfa.harvard.edu; rix@as.arizona.edu; ckeeton@as.arizona.edu; jmunoz@cfa.harvard.edu NR 104 TC 208 Z9 208 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 1 PY 1999 VL 523 IS 2 BP 617 EP 632 DI 10.1086/307758 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239MG UT WOS:000082771500014 ER PT J AU Caselli, P Walmsley, CM Tafalla, M Dore, L Myers, PC AF Caselli, P Walmsley, CM Tafalla, M Dore, L Myers, PC TI CO depletion in the starless cloud core L1544 SO ASTROPHYSICAL JOURNAL LA English DT Article DE dust, extinction; ISM : individual (L1544); ISM : molecules ID INTER-STELLAR CLOUDS; INTERSTELLAR-MEDIUM; PROTOSTELLAR CORES; COLUMN DENSITIES; DUST OPACITIES; DENSE CORES; SOLID CO; REGIONS; ICES; EXTINCTION AB We present evidence for CO depletion toward the starless cloud core L1544. A comparison between (CO)-O-17 and the 1.3 mm continuum dust emission shows that CO is depleted by a factor of similar to 10 at the dust peak. Our observations are consistent with a model in which CO is condensed out onto dust grains at densities above n(d) similar to 10(5) cm(-3). The corresponding radius of the "depleted region" is r(d) similar to 6500 AU, and we find that this depletion causes 2.3 M. of gas to be lost to view in molecular line emission. Optically thin high-density tracers, such as (HCO+)-O-18 and (DCO+)-C-13, show double-peaked profiles which suggest that we are observing superposed emission from the foreground and background undepleted layers with density below n(d). We conclude from our data that the core is probably young (similar to 10(4) yr old) and collapsing. For the component at V-LSR = 7.1 km s(-1) in this line of sight, we estimate [DCO+]/[HCO+] = 0.12 +/- 0.02, which is larger by a factor of order 2 than values derived in other dense cloud cores. C1 Osservatorio Astrofis Arcetri, I-50125 Florence, Italy. Natl Astron Observ, E-28800 Madrid, Spain. Univ Bologna, Dipartimento Chim G Ciamician, I-40126 Bologna, Italy. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Caselli, P (reprint author), Osservatorio Astrofis Arcetri, Largo E Fermi 5, I-50125 Florence, Italy. NR 34 TC 193 Z9 193 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 OCT 1 PY 1999 VL 523 IS 2 BP L165 EP L169 DI 10.1086/312280 PN 2 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239MJ UT WOS:000082771700016 ER PT J AU Israelian, G Lobel, A Schmidt, MR AF Israelian, G Lobel, A Schmidt, MR TI The yellow hypergiants HR 8752 and rho Cassiopeiae near the evolutionary border of instability SO ASTROPHYSICAL JOURNAL LA English DT Article DE stars : atmospheres; stars : individual (HR 8752, rho Cassiopeiae); stars : late-type; supergiants ID COOL HYPERGIANT; MASS-LOSS; STARS; IRC+10420 AB High-resolution near-ultraviolet spectra of the yellow hypergiants HR 8752 and rho Cassiopeiae indicate high effective temperatures, placing both stars near the low-T-eff border of the "yellow evolutionary void." At present, the temperature of HR 8752 is higher than ever. For this star we found T-eff = 7900 +/- 200 K, whereas rho Cassiopeiae has T-eff = 7300 +/- 200 K. Both HR 8752 and rho Cassiopeiae have developed strong stellar winds with V-infinity similar or equal to 120 and V-infinity similar or equal to 100 km s(-1), respectively. For HR 8752 we estimate an upper limit for the spherically symmetric mass loss of 6.7 x 10(-6) M. yr(-1). Over the past decades two yellow hypergiants appear to have approached an evolutionary phase, which has never been observed before. We present the first spectroscopic evidence of the blueward motion of a cool super/hypergiant on the H-R diagram. C1 Inst Astrofis Canarias, E-38200 La Laguna, Spain. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. N Copernicus Astron Ctr, PL-87100 Torun, Poland. RP Israelian, G (reprint author), Inst Astrofis Canarias, E-38200 La Laguna, Spain. NR 28 TC 14 Z9 14 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 OCT 1 PY 1999 VL 523 IS 2 BP L145 EP L149 DI 10.1086/312283 PN 2 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239MJ UT WOS:000082771700012 ER PT J AU Naab, T Burkert, A Hernquist, L AF Naab, T Burkert, A Hernquist, L TI On the formation of boxy and disky elliptical galaxies SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : evolution; galaxies : interactions; galaxies : structure; methods : numerical ID MERGER REMNANTS; ISOPHOTE SHAPES; TRANSFORMATIONS; GASDYNAMICS; PROGENITORS; PROFILES; BULGES AB The origin of boxy and disky elliptical galaxies is investigated. The results of two collisioless N-body simulations of spiral-spiral mergers with mass ratios of 1 : 1 and 3 : 1 are discussed, and the projected properties of the merger remnants are investigated. It is shown that the equal-mass merger leads to an anisotropic, slowly rotating system with preferentially boxy isophotes and significant minor-axis rotation. The unequal-mass merger results in the formation of a rotationally supported elliptical galaxy with disky isophotes and small minor-axis rotation. The observed scatter in the kinematical and isophotal properties of both classes of elliptical galaxies can be explained by projection effects. C1 Max Planck Inst Astron, D-69117 Heidelberg, Germany. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Naab, T (reprint author), Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany. NR 32 TC 73 Z9 73 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 OCT 1 PY 1999 VL 523 IS 2 BP L133 EP L136 DI 10.1086/312275 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239MJ UT WOS:000082771700009 ER PT J AU Dumbacher, JP AF Dumbacher, JP TI Evolution of toxicity in pitohuis: I. Effects of homobatrachotoxin on chewing lice (order Phthiraptera) SO AUK LA English DT Article ID ROCK DOVES; BIRDS; ECTOPARASITES; PARASITES; DEFENSE AB Birds in the genus Pitohui carry the potent neurotoxin homobatrachotoxin in their skin and feathers. In this study, I tested whether homobatrachotoxin can repel or kill chewing lice (order Phthiraptera). When individual feather lice were offered a choice of two feathers on which to feed or take shelter, the lice preferred nontoxic feathers to bathers of the most toxic pitohui species, Pitohui dichrous. Moreover, the presence of toxic P. dichrous feathers significantly shortened the life span of captive bather lice. These results suggest that homobatrachotoxin repels and kills lice and may thus protect pitohuis against lice infestation. C1 Univ Chicago, Dept Ecol & Evolut, Chicago, IL 60637 USA. RP Dumbacher, JP (reprint author), Smithsonian Inst, Natl Zool Pk, Mol Genet Lab, 3001 Connecticut Ave NW, Washington, DC 20008 USA. NR 28 TC 35 Z9 37 U1 2 U2 11 PU AMER ORNITHOLOGISTS UNION PI LAWRENCE PA ORNITHOLOGICAL SOC NORTH AMER PO BOX 1897, LAWRENCE, KS 66044-8897 USA SN 0004-8038 J9 AUK JI AUK PD OCT PY 1999 VL 116 IS 4 BP 957 EP 963 PG 7 WC Ornithology SC Zoology GA 253XZ UT WOS:000083583600009 ER PT J AU Novotny, V Basset, Y Auga, J Boen, W Dal, C Drozd, P Kasbal, M Isua, B Kutil, R Manumbor, M Molem, K AF Novotny, V Basset, Y Auga, J Boen, W Dal, C Drozd, P Kasbal, M Isua, B Kutil, R Manumbor, M Molem, K TI Predation risk for herbivorous insects on tropical vegetation: A search for enemy-free space and time SO AUSTRALIAN JOURNAL OF ECOLOGY LA English DT Article DE ants; Ficus; Papua New Guinea; predators; rain forest; termite baits ID PAPUA-NEW-GUINEA; RAIN-FOREST; LEPIDOPTERAN LARVAE; ANT; ARTHROPODS; COMMUNITIES; ABUNDANCE; SAPLINGS; PLANTS; AMAZON AB Spatial and temporal variability in predation risk for herbivores on 13 rainforest species of Ficus (Moraceae) in Papua New Guinea was studied in order to assess whether predator-free refuges exist on their foliage and if so, whether herbivorous insects concentrate their activity in such refugia. Predation risk from invertebrate predators was measured as the disappearance rate of live termites set up as baits on the foliage. By far the most important predators were ants, accounting for 77% of attacks. No consistent differences in predation rate between Ficus species were found so that tree identity could not be used as an indicator of enemy-free space. Predation risk was highly variable among conspecific trees and also changed rapidly in time, over periods as short as 10 days. Such short-term and unpredictable predator-free refuges may be difficult for herbivores to find and exploit. Predation risk during the day was three times higher than during the night, but abundance of herbivores on the foliage was also higher during the day. Thus, night was confirmed as a relatively enemy-free time which, however, was not exploited by herbivores. C1 Acad Sci Czech Republ, Inst Entomol, CR-37005 Ceske Budejovice, Czech Republic. Univ S Bohemia, Ceske Budejovice 37005, Czech Republic. Smithsonian Trop Res Inst, Balboa, Ancon, Panama. Insect Ecol Mangi Makarangi Project, Madang, Papua N Guinea. RP Novotny, V (reprint author), Inst Ecol Project, POB 604, Madang, Papua N Guinea. RI Drozd, Pavel/J-3943-2013; Basset, Yves/B-6642-2014; Novotny, Vojtech/G-9434-2014 OI Drozd, Pavel/0000-0002-4602-8856; Novotny, Vojtech/0000-0001-7918-8023 NR 43 TC 34 Z9 37 U1 3 U2 13 PU BLACKWELL SCIENCE ASIA PI CARLTON PA 54 UNIVERSITY ST, P O BOX 378, CARLTON, VICTORIA 3053, AUSTRALIA SN 0307-692X J9 AUST J ECOL JI Aust. J. Ecol. PD OCT PY 1999 VL 24 IS 5 BP 477 EP 483 DI 10.1046/j.1440-169x.1999.00987.x PG 7 WC Ecology SC Environmental Sciences & Ecology GA 240UT UT WOS:000082845600001 ER PT J AU Wagner, WL Shannon, RK AF Wagner, WL Shannon, RK TI Angiosperm types from the Hawaiian collections of A. A. Heller SO BRITTONIA LA English DT Article AB The numbering system used by A. A. Heller for his 1895 Hawaiian collections has led to confusion regarding which specimens should be considered types. As part of a larger study of Hawaiian angiosperm types we have examined many of Heller's specimens and analyzed their status as types. We present the status of all specimens we have examined as well as those we are aware of from the literature. We have also constructed itineraries for Heller's collecting activities on his trip to the Hawaiian Islands on the islands of O'ahu and Kaua'i. Nomenclatural notes are given for all angiosperm basionyms based on Heller's Hawaiian collections. Lectotypifications are provided for Cyperus hillebrandii Boeck. var. helleri Kuk., Cyrtandra gayana A. Heller, Cyrtandra longifolia (Wawra) Hillebr. ex C. B. Clarke var. wahiawae A. Heller ex Rock, Euphorbia sparsiflora A. Heller, Isodendrion subsessilifolium A. Heller, Lobelia tortuosa A. Heller, Nania tremuloides A. Heller, Pelea microcarpa A. Heller, and Suttonia angustifolia Mez. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, Washington, DC 20560 USA. RP Wagner, WL (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, MRC 166, Washington, DC 20560 USA. NR 14 TC 3 Z9 4 U1 2 U2 3 PU NEW YORK BOTANICAL GARDEN PI BRONX PA PUBLICATIONS DEPT, BRONX, NY 10458 USA SN 0007-196X J9 BRITTONIA JI Brittonia PD OCT-DEC PY 1999 VL 51 IS 4 BP 422 EP 438 DI 10.2307/2666526 PG 17 WC Plant Sciences SC Plant Sciences GA 268QB UT WOS:000084426100008 ER PT J AU Berger, J Testa, JW Roffe, T Monfort, SL AF Berger, J Testa, JW Roffe, T Monfort, SL TI Conservation endocrinology: a noninvasive tool to understand relationships between carnivore colonization and ecological carrying capacity SO CONSERVATION BIOLOGY LA English DT Article ID PAPIO-CYNOCEPHALUS-CYNOCEPHALUS; YELLOWSTONE-NATIONAL-PARK; FECAL STEROIDS; ESTROUS-CYCLE; MOOSE; PREGNANCY; SERUM; METABOLITES; DIAGNOSIS; MORTALITY AB Reproductive technology, especially the diagnosis of pregnancy by radioimmunoassay of focal steroid metabolites, is an important component of captive propagation, but its role in our understanding of ecological interactions and in situ biological restoration has been more limited. Where large herbivores have been "released" from predation by the extirpation of carnivores, controversy often exists about possible detrimental effects at the ecosystem level. A related concern is that the reestablishment of large carnivores may decrease the availability of prey populations for human subsistence. We suggest that pregnancy assays can be a valuable tool to help distinguish between the roles of predation versus food-imposed limitations on population size and their effects on juvenile recruitment in wild species. We explored this issue through analyses of fecal progestagen concentration (FPC) levels to document pregnancy in moose (Alces alces) in the southern Greater Yellowstone Ecosystem, a site where wolves (Canis lupus) and grizzly bears (Ursus arctos) are recolonizing former habitats after an absence of more than 60 years. Pregnancy was clearly discernible (mean FPC for pregnant and nonpregnant females, respectively: 10.60 vs. 2.57 mu g/g; p < 0.0001). Among the potential confounding variables that need to be considered if FPC is applied to ecological and demographic questions are whether baseline values are affected by handling, whether neonate survival has been assessed, and whether sampling efforts are directed at both pregnant and nonpregnant animals. With these issues accounted for, the local moose population experienced juvenile survival rates among the highest in North America. Pregnancy rates, however, dropped from 90% in 1966 to about 75% today, rendering them in the lowest fifteenth percentile among moose populations in North America. Our findings suggest that a relatively low frequency of juvenile moose is not the likely results of predation, and they illustrate how endocrinology can be applied to issues involving reproductive events within an ecological context. They also affirm that noninvasive and generally inexpensive endocrinological procedures will be applicable to understanding interactions between recolonizing predators and prey, an issue that will continue to arise because of global restoration efforts, and to the study of rare ungulates in remote systems where data on reproductive events are difficult to obtain. C1 Univ Nevada, Program Ecol Evolut & Conservat Biol, Reno, NV 89512 USA. Wildlife Conservat Soc, Moose, WY 83012 USA. Alaska Dept Fish & Game, Div Wildlife Conservat, Anchorage, AK 99518 USA. Montana State Univ, Biol Resources Div, US Geol Survey, Bozeman, MT 59717 USA. Smithsonian Inst, Conservat & Res Ctr, Front Royal, VA 22630 USA. RP Berger, J (reprint author), Univ Nevada, Program Ecol Evolut & Conservat Biol, Reno, NV 89512 USA. EM berger@unr.edu NR 66 TC 26 Z9 29 U1 2 U2 17 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0888-8892 EI 1523-1739 J9 CONSERV BIOL JI Conserv. Biol. PD OCT PY 1999 VL 13 IS 5 BP 980 EP 989 DI 10.1046/j.1523-1739.1999.98521.x PG 10 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 240JD UT WOS:000082821400008 ER PT J AU Lovette, IJ Bermingham, E Ricklefs, RE AF Lovette, IJ Bermingham, E Ricklefs, RE TI Mitochondrial DNA phylogeography and the conservation of endangered Lesser Antillean Icterus orioles SO CONSERVATION BIOLOGY LA English DT Article ID EVOLUTIONARY RELATIONSHIPS; NUCLEOTIDE-SEQUENCES; SHINY COWBIRD; WEST-INDIES; BIOGEOGRAPHY; GENE; PLEISTOCENE; SYSTEMATICS; POPULATIONS; SPECIATION AB Recent natural and anthropogenic disturbances have endangered two of the three oriole species endemic to single islands in the Lesser Antilles. The ongoing eruption of the Soufriere Hills volcano may have doomed the Montserrat Oriole (Icterus oberi), whereas high levels of nest parasitism by a cowbird threaten the Martinique oriole (I. bonana). These orioles and related antillean and Central American forms have been considered part of the Icterus dominicensis superspecies complex, but the taxonomic status of the different antillean island populations has been long debated. To investigate levels of evolutionary differentiation among threatened Lesser Antillean orioles, we analyzed 2507 nucleotides of protein-coding mitochondrial DNA (mtDNA) sequence from orioles on Martinique, Montserrat, St. Lucia (I. laudabilis), Puerto Rico (I. dominicensis dominicensis), Mexico ( I.d. prosthemelas), and three Icterus outgroup species. Phylogenetic analyses of the mtDNA data supported the monophyly of Antillean members of the I. dominicensis complex and identified a star-like pattern of relationship among them. Mitochondrial distances between the Antillean populations were large (4.5-5.8% nucleotide divergence) and suggested that the Lesser Antillean orioles have been isolated evolutionarily from one another since the late Pliocene. The oriole taxa on Montserrat, Martinique, and St. Lucia meet species criteria under the phylogenetic species concept and represent evolutionarily significant units. The impending extinction of the phylogenetically unique montserrat oriole highlights the vulnerability of island endemics to habitat degradation followed by rare and unpredictable natural catastrophes. C1 Univ Penn, Dept Biol, Philadelphia, PA 19104 USA. Smithsonian Trop Res Inst, Balboa, Panama. Univ Missouri, Dept Biol, St Louis, MO 63121 USA. RP Lovette, IJ (reprint author), Univ Penn, Dept Biol, Philadelphia, PA 19104 USA. RI Lovette, Irby/P-3477-2014 NR 57 TC 29 Z9 31 U1 1 U2 11 PU BLACKWELL SCIENCE INC PI MALDEN PA 350 MAIN ST, MALDEN, MA 02148 USA SN 0888-8892 J9 CONSERV BIOL JI Conserv. Biol. PD OCT PY 1999 VL 13 IS 5 BP 1088 EP 1096 DI 10.1046/j.1523-1739.1999.98300.x PG 9 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 240JD UT WOS:000082821400021 ER PT J AU Glenn, TC Stephan, W Braun, MJ AF Glenn, TC Stephan, W Braun, MJ TI Effects of a population bottleneck on Whooping Crane mitochondrial DNA variation SO CONSERVATION BIOLOGY LA English DT Article ID WOMBAT LASIORHINUS-KREFFTII; GENETIC-VARIATION; GRUS-AMERICANA; CONTROL REGION; CONSERVATION; POLYMORPHISM; EVOLUTION; MODELS; NUMBER; SITES AB The Whooping Crane (Grus americana) is an endangered bird that suffered a severe population bottleneck; only 14 adults survived in 1938. We assessed the genetic effect of this human-caused bottleneck by sequencing 314 base pairs (bp) of the mitochondrial DNA control region from cranes that lived before, during and after this bottleneck. The maximum length of DNA amplifiable from museum specimens was negatively correlated with age, and only 10 of 153 specimens yielded the entire 314 bp sequence. Six haplotypes were present among the prebottleneck individuals sequenced, and only one of these persists in the modern population. The most common modern haplotype was in low frequency in the prebottleneck population, which demonstrates the powerful effect of genetic drift in changing allele frequencies in very small populations. By combining all available data, we show that no more than one-third of the prebottleneck haplotypes survived the human-caused population bottleneck. High levels of variation of substitution rates among nucleotide sites prevented us from estimating the prebottleneck population size. Our data will be incorporated into the captive breeding program to allow better management decisions regarding the preservation of current genetic diversity. These data offer the first glimpse into the genetic toll this species has paid for human activities. C1 Univ Maryland, Dept Zool, College Pk, MD 20742 USA. Smithsonian Inst, Lab Mol Systemat, Washington, DC 20560 USA. RP Glenn, TC (reprint author), Savannah River Ecol Lab, Drawer E, Aiken, SC 29802 USA. EM glenn@srel.edu RI Glenn, Travis/A-2390-2008 NR 54 TC 96 Z9 102 U1 3 U2 38 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0888-8892 EI 1523-1739 J9 CONSERV BIOL JI Conserv. Biol. PD OCT PY 1999 VL 13 IS 5 BP 1097 EP 1107 DI 10.1046/j.1523-1739.1999.97527.x PG 11 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 240JD UT WOS:000082821400022 ER PT J AU Whigham, DF Twilley, RR Feller, IC AF Whigham, DF Twilley, RR Feller, IC TI Within-stand nutrient cycling in wetland ecosystems SO ECOLOGY LA English DT Editorial Material DE arctic; boreal; decomposition; forested; herbaceous; nitrogen; nutrient-use efficiency; phosphorus; subtropical; temperate; tropical; wetlands C1 Smithsonian Inst, Washington, DC 20560 USA. Univ SW Louisiana, Lafayette, LA 70504 USA. RP Whigham, DF (reprint author), Smithsonian Inst, Washington, DC 20560 USA. OI Whigham, Dennis/0000-0003-1488-820X; Feller, Ilka/0000-0002-6391-1608 NR 0 TC 1 Z9 2 U1 0 U2 10 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 1707 H ST NW, STE 400, WASHINGTON, DC 20006-3915 USA SN 0012-9658 J9 ECOLOGY JI Ecology PD OCT PY 1999 VL 80 IS 7 BP 2137 EP 2138 PG 2 WC Ecology SC Environmental Sciences & Ecology GA 243QU UT WOS:000083009400001 ER PT J AU Aerts, R Verhoeven, JTA Whigham, DF AF Aerts, R Verhoeven, JTA Whigham, DF TI Plant-mediated controls on nutrient cycling in temperate fens and bogs SO ECOLOGY LA English DT Article DE bogs; temperate; climate control of nutrient cycling; decomposition; evergreen fens; temperate; leaf life-span; litter chemistry effects on decomposition; mineralization; nutrient cycling; nutrient resorption; nutrient-use efficiency; Sphagnum ID NITROGEN USE EFFICIENCY; LEAF LIFE-SPAN; LITTER DECOMPOSITION; CAREX-ROSTRATA; ELEMENT CONCENTRATIONS; WETLAND ECOSYSTEMS; LARIX-LARICINA; RAISED BOG; SPHAGNUM; GROWTH AB This paper reports on patterns in plant-mediated processes that determine the rate of nutrient cycling in temperate fens and bogs. We linked leaf-level nutrient dynamics with leaf-litter decomposition and explored how the observed patterns were reflected in nutrient cycling at the ecosystem level. Comparisons were made among growth forms (evergreen and deciduous shrubs and trees, graminoids and Sphagnum mosses) and between mire types (fens and bogs). A literature review showed that the predominant growth form was more important as a determinant of leaf-level nutrient-use efficiency (NUE) than mire type (fen vs. bog). Evergreens had the highest N and P use efficiency. The growth form differences in NUE were mainly determined by differences in N and P concentrations in mature leaves and not by differences in resorption efficiency from senescing leaves. Sphagnum leaves had lower N and P concentrations than the other growth forms, but because of a lack of data on nutrient resorption efficiency the NUE of these mosses could not be calculated. Nitrogen use efficiency did not differ among fen and bog species, whereas bog species had a higher P use efficiency than fen species. However, a complete evaluation of mire-type or growth-form effects on NUE is only possible when data become available about nutrient resorption from senescing Sphagnum leaves. As leaf-level NUE is negatively correlated with leaf-litter nutrient concentrations, then is a direct link between NUE and litter decomposition rate. Rates of litter decomposition of Sphagnum mosses are lower than in the other growth forms, but there is still much speculation about possible reasons. The role of litter chemistry of Sphagnum mosses (including decay inhibitors and decay-resistant compounds) in decomposition especially warrants further study. The strongly deviating nutritional ecology of Sphagnum mosses clearly distinguishes fens and bogs from other ecosystems. Moreover, N and P concentrations in mature leaves from vascular plant species from fens and bogs are in almost all cases lower and leaf-level N use efficiency is higher than in species from other ecosystems, irrespective of the growth form considered. Both literature data and data from a comparative study on soil nutrient cycling in temperate fens and bogs in the United States (Maryland), The Netherlands, and Poland showed that nutrient mineralization did not differ clearly between fens and bogs. The comparative study further showed that cellulose decomposition in bogs was lower than in fens and that nutrient mineralization was higher in forested than in herbaceous mires. The occurrence of dominant growth forms was clearly related to soil nutrient-cycling processes, and observed patterns were in agreement with patterns in the components of NUE as found in the literature study. We conclude that a protocol with standardized procedures for measuring various nutrient-cycling process rates that is used by scientists in various wetland types and geographical regions is a useful tool for unravelling large-scale patterns in soil nutrient-cycling processes in wetlands and for linking plant-mediated nutrient dynamics with ecosystem nutrient-cycling processes. C1 Univ Utrecht, Dept Plant Ecol & Evolut Biol, NL-3508 TB Utrecht, Netherlands. Smithsonian Environm Res Ctr, Edgewater, MD 20137 USA. RP Aerts, R (reprint author), Vrije Univ Amsterdam, Dept Syst Ecol, De Boelelaan 1087, NL-1081 HV Amsterdam, Netherlands. RI Verhoeven, Jos/B-9514-2011; OI Whigham, Dennis/0000-0003-1488-820X NR 90 TC 202 Z9 218 U1 10 U2 119 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 1707 H ST NW, STE 400, WASHINGTON, DC 20006-3915 USA SN 0012-9658 J9 ECOLOGY JI Ecology PD OCT PY 1999 VL 80 IS 7 BP 2170 EP 2181 DI 10.1890/0012-9658(1999)080[2170:PMCONC]2.0.CO;2 PG 12 WC Ecology SC Environmental Sciences & Ecology GA 243QU UT WOS:000083009400004 ER PT J AU Feller, IC Whigham, DF O'Neill, JP McKee, KL AF Feller, IC Whigham, DF O'Neill, JP McKee, KL TI Effects of nutrient enrichment on within-stand cycling in a mangrove forest SO ECOLOGY LA English DT Review DE Belize; mangrove forests; decomposition; belowground; leaching; mangrove ecosystem; nutrient availability; nutrient cycling processes; plant mediated; nutrient ratios; nutrient-resorption efficiency; nutrient-use efficiency; P enrichment; effects on nutrient cycling; Rhizophora mangle; sclerophylly ID HARDWOOD LEAF LITTER; DESERT EVERGREEN SHRUB; USE EFFICIENCY; PHOSPHORUS AVAILABILITY; EXPERIMENTAL GRADIENT; DECOMPOSITION RATES; TROPICAL AUSTRALIA; MINERAL-NUTRITION; RHIZOPHORA-MANGLE; LARREA-TRIDENTATA AB Within-stand nutrient cycling is dependent on many factors, including primary productivity, nutrient-use efficiency, nutrient resorption, sclerophylly, decomposition, nutritional quality of plant tissue, and allocation to defense. The efficiency of these plant-mediated processes depends on nutrient availability in the environment and inherent functional properties of plants. However, little is known about how nutrient availability will affect these processes in forested wetlands in the tropics. In a factorial experiment we fertilized 48 dwarfed Rhizophora mangle (red mangrove) trees along tidal-elevation and water-depth gradients at Twin Gays, a range of intertidal, peat-based offshore mangrove islands in Belize, Central America. Initial results indicated that phosphorus (P) deficiency is a major factor limiting primary productivity. Phosphorus-fertilized trees had a significant decrease in P-use efficiency and P-resorption efficiency, but a significant increase in nitrogen (N)-use efficiency and N-resorption efficiency in their leaves compared with controls and N-fertilized trees. Sclerophylly decreased dramatically in P-fertilized trees, while the nutritional quality of the plant tissue increased. Phosphorus fertilization did not affect P leaching from green leaves. We found no fertilizer effect on the decomposition rates of leaf tissue, possibly due to higher phenolic concentrations in the P-fertilized trees compared with controls and N-fertilized trees. However, belowground decomposition of cotton strips increased in the substrate associated with P-fertilized trees. Environmental conditions related to position along a tidal gradient may be as important as nutrients in controlling belowground decomposition. C1 Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. Louisiana State Univ, Wetland Biogeochem Inst, Baton Rouge, LA 70803 USA. RP Feller, IC (reprint author), Smithsonian Environm Res Ctr, POB 28, Edgewater, MD 21037 USA. RI McKee, Karen/D-1365-2014; OI McKee, Karen/0000-0001-7042-670X; Whigham, Dennis/0000-0003-1488-820X; Feller, Ilka/0000-0002-6391-1608 NR 113 TC 97 Z9 108 U1 5 U2 50 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 1707 H ST NW, STE 400, WASHINGTON, DC 20006-3915 USA SN 0012-9658 J9 ECOLOGY JI Ecology PD OCT PY 1999 VL 80 IS 7 BP 2193 EP 2205 DI 10.2307/176903 PG 13 WC Ecology SC Environmental Sciences & Ecology GA 243QU UT WOS:000083009400006 ER PT J AU Rice, RA AF Rice, RA TI A place unbecoming: The coffee farm of northern Latin America SO GEOGRAPHICAL REVIEW LA English DT Article DE biodiversity; coffee; landscape; Latin America; place; shade ID TROPICAL AGROECOSYSTEM; LANDSCAPE; TRANSFORMATION; PLANTATIONS; SHADE AB This article examines recent transformations of the coffee landscape of northern Latin America through the optic of "place as process." As coffee became the most important regional export crop, its "place" evolved. Coffee lands in northern Latin America now embrace 3.1 million hectares, often contiguous across international borders. Like many agricultural systems, coffee has succumbed to intensification, a process termed "technification" in the Latin American setting. The result is a landscape mosaic in which a traditional agro-forest coffee system coexists with coffee lands transformed by modernization. The institutional forces behind this process, as well as some of its social and ecological consequences, are discussed. C1 Smithsonian Migratory Bird Ctr, Natl Zool Pk, Washington, DC 20008 USA. RP Rice, RA (reprint author), Smithsonian Migratory Bird Ctr, Natl Zool Pk, Washington, DC 20008 USA. NR 73 TC 28 Z9 29 U1 0 U2 5 PU AMER GEOGRAPHICAL SOC PI NEW YORK PA 120 WALL ST, STE 100, NEW YORK, NY 10005 USA SN 0016-7428 J9 GEOGR REV JI Geogr. Rev. PD OCT PY 1999 VL 89 IS 4 BP 554 EP 579 DI 10.2307/216102 PG 26 WC Geography SC Geography GA 336FV UT WOS:000088292000005 PM 20662186 ER PT J AU Hungate, BA Dijkstra, P Johnson, DW Hinkle, CR Drake, BG AF Hungate, BA Dijkstra, P Johnson, DW Hinkle, CR Drake, BG TI Elevated CO2 increases nitrogen fixation and decreases soil nitrogen mineralization in Florida scrub oak SO GLOBAL CHANGE BIOLOGY LA English DT Article DE elevated atmospheric CO2; Florida; Galactia elliottii; gross mineralization; nitrogen fixation; scrub oak; soil microbial biomass; soil nitrogen cycling ID CARBON-DIOXIDE ENRICHMENT; SYMBIOTIC N-2 FIXATION; ROOT NODULE ACTIVITY; ATMOSPHERIC CO2; WHITE CLOVER; ANNUAL GRASSLAND; TRIFOLIUM-REPENS; GROWTH-RESPONSE; LONG-TERM; PLANTS AB We report changes in nitrogen cycling in Florida scrub oak in response to elevated atmospheric CO2 during the first 14 months of experimental treatment. Elevated CO2 stimulated above-ground growth, nitrogen mass, and root nodule production of the nitrogen-fixing vine, Galactia elliottii Nuttall. During this period, elevated CO2 reduced rates of gross nitrogen mineralization in soil, and resulted in lower recovery of nitrate on resin lysimeters. Elevated CO2 did not alter nitrogen in the soil microbial biomass, but increased the specific rate of ammonium immobilization (NH4+ immobilized per unit microbial N) measured over a 24-h period. Increased carbon input to soil through greater root growth combined with a decrease in the quality of that carbon in elevated CO2 best explains these changes. These results demonstrate that atmospheric CO2 concentration influences both the internal cycling of nitrogen (mineralization, immobilization, and nitrification) as well as the processes that regulate total ecosystem nitrogen mass (nitrogen fixation and nitrate leaching) in Florida coastal scrub oak. If these changes in nitrogen cycling are sustained, they could cause long-term feedbacks to the growth responses of plants to elevated CO2. Greater nitrogen fixation and reduced leaching could stimulate nitrogen-limited plant growth by increasing the mass of labile nitrogen in the ecosystem. By contrast, reduced nitrogen mineralization and increased immobilization will restrict the supply rate of plant-available nitrogen, potentially reducing plant growth. Thus, the net feedback to plant growth will depend on the balance of these effects through time. C1 Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. Desert Res Inst, Reno, NV USA. Dynamac Corp, Kennedy Space Ctr, FL 32899 USA. RP Hungate, BA (reprint author), No Arizona Univ, Dept Biol Sci, Box 5640, Flagstaff, AZ 86011 USA. RI Hungate, Bruce/F-8991-2011 OI Hungate, Bruce/0000-0002-7337-1887 NR 71 TC 83 Z9 100 U1 4 U2 41 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 1354-1013 J9 GLOB CHANGE BIOL JI Glob. Change Biol. PD OCT PY 1999 VL 5 IS 7 BP 781 EP 789 DI 10.1046/j.1365-2486.1999.00275.x PG 9 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 237GH UT WOS:000082646900004 ER PT J AU Huber, BT Leckie, RM Norris, RD Bralower, TJ CoBabe, E AF Huber, BT Leckie, RM Norris, RD Bralower, TJ CoBabe, E TI Foraminiferal assemblage and stable isotopic change across the Cenomanian-Turonian boundary in the subtropical North Atlantic SO JOURNAL OF FORAMINIFERAL RESEARCH LA English DT Article ID WESTERN INTERIOR USA; PLANKTONIC-FORAMINIFERA; SEQUENCE STRATIGRAPHY; EVOLUTION; BIOSTRATIGRAPHY; TEMPERATURES; RADIOLARIA; CARBONATE; CYCLES; SEAWAY AB The Cenomanian/Turonian boundary interval (CTBI) at Site 1050 (30 degrees 6'N, 76 degrees 14'W) was investigated to characterize climatic and oceanographic changes during the Oceanic Anoxic Event that was associated with it (OAE 2). Because of unusually good foraminiferal preservation for sediments of this age, we have obtained an unaltered oxygen and carbon isotope profile and an accompanying record of planktic and benthic foraminifer abundance changes across the OAE 2 interval. Biostratigraphic, sedimentologic, and chemostratigraphic analyses indicate that more than 0.5 m,y. between the onset and tail end of OAE 2 are missing. This explains why organic-rich sediments are absent from the Site 1050 sequence and why the planktic and benthic carbon isotope shifts are minor (similar to 0.8 parts per thousand) compared with the most complete OAE 2 sections. While planktic species diversity shows relatively minor change across the OAE 2 interval, extinction of the rotaliporids and Globigerinelloides bentonensis, a shift to Heterohelix-dominated assemblages, and increased abundance of helvetoglobotruncanids at the onset of OAE 2 cause a dramatic change in the planktic foraminifer assemblage composition. The rotaliporid extinction occurs at the level where middle bathyal temperatures are estimated to have increased from 15 to 19 degrees C, which is warmer than any other time during the Cretaceous and Cenozoic, This deep water warming may have caused a breakdown in the vertical structure of the water column, and could explain the extinction of deeper dwelling planktic species, including Rotalipora and G. bentonensis. On the other hand, sea surface temperature estimates based on planktic foraminiferal delta(18)O values (corrected for salinity) remain steady throughout the CTBI, varying between 23 to 26 degrees C, The presence of volcaniclastic sediments within the OAE 2 interval at Site 1050 is consistent with previous suggestions that the CTBI was a time of anonymously high rates of CO2 flux into the atmosphere and oceans during a major phase of explosive volcanic activity and large igneous province emplacement in the Caribbean and other regions worldwide. Further investigation of the CTBI is needed to establish whether increased pCO(2) can be accepted as the primary forcing mechanism for the middle Cretaceous "supergreenhouse". C1 Smithsonian Inst, Dept Paleobiol, Washington, DC 20560 USA. Univ Massachusetts, Dept Geosci, Amherst, MA 01003 USA. Woods Hole Oceanog Inst, Woods Hole, MA 02543 USA. Univ N Carolina, Dept Geol Sci, Chapel Hill, NC 27599 USA. RP Huber, BT (reprint author), Smithsonian Inst, Dept Paleobiol, NHB 121, Washington, DC 20560 USA. OI Leckie, R. Mark/0000-0002-7311-2180 NR 74 TC 80 Z9 86 U1 1 U2 13 PU CUSHMAN FOUNDATION FORAMINIFERAL RES PI CAMBRIDGE PA MUSEUM COMPARATIVE ZOOLOGY, DEPT INVERTEBRATE PALEONTOLOGY 26 OXFORD ST, HARVARD UNIV, CAMBRIDGE, MA 02138 USA SN 0096-1191 J9 J FORAMIN RES JI J. Foraminifer. Res. PD OCT PY 1999 VL 29 IS 4 BP 392 EP 417 PG 26 WC Paleontology SC Paleontology GA 253XN UT WOS:000083582400006 ER PT J AU Peled, S Tseng, CH Sodickson, AA Mair, RW Walsworth, RL Cory, DG AF Peled, S Tseng, CH Sodickson, AA Mair, RW Walsworth, RL Cory, DG TI Single-shot diffusion measurement in laser-polarized gas SO JOURNAL OF MAGNETIC RESONANCE LA English DT Article DE hyperpolarized noble gases; Xe-129; He-3; bounded diffusion ID HYPERPOLARIZED HE-3; XE-129; NMR; XENON; SEQUENCE; NUCLEI AB A single-shot pulsed gradient stimulated echo sequence is introduced to address the challenges of diffusion measurements of laser polarized He-3 and Xe-129 gas. Laser polarization enhances the NMR sensitivity of these noble gases by >10(3), but creates an unstable, nonthermal polarization that is not readily renewable, A new method is presented which permits parallel acquisition of the several measurements required to determine a diffusive attenuation curve. The NMR characterization of a sample's diffusion behavior can be accomplished in a single measurement, using only a single polarization step. As a demonstration, the diffusion coefficient of a sample of laser-polarized Xe-129 gas is measured via this method. (C) 1999 Academic Press. C1 MIT, Dept Nucl Engn, Cambridge, MA 02139 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Peled, S (reprint author), Columbia Presbyterian Med Ctr, Hatch NMR Ctr, 710 W168th St, New York, NY 10032 USA. RI Peled, Sharon/F-8590-2015 FU NCRR NIH HHS [P41 RR000995-270067]; NIBIB NIH HHS [P41 EB002026, P41 EB002026-280067]; NIGMS NIH HHS [R01-GM52026] NR 22 TC 30 Z9 31 U1 0 U2 8 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1090-7807 J9 J MAGN RESON JI J. Magn. Reson. PD OCT PY 1999 VL 140 IS 2 BP 320 EP 324 DI 10.1006/jmre.1999.1850 PG 5 WC Biochemical Research Methods; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Biochemistry & Molecular Biology; Physics; Spectroscopy GA 243WL UT WOS:000083020400003 PM 10497039 ER PT J AU Price, MD Somaroo, SS Tseng, CH Gore, JC Fahmy, AF Havel, TF Cory, DG AF Price, MD Somaroo, SS Tseng, CH Gore, JC Fahmy, AF Havel, TF Cory, DG TI Construction and implementation of NMR quantum logic gates for two spin systems SO JOURNAL OF MAGNETIC RESONANCE LA English DT Article ID ARBITRARY FLIP ANGLES; INDEPENDENT ROTATIONS; COMPUTATION; PHASES AB The implementation of small prototype quantum computers has been studied through ensemble quantum computing via NMR measurements. In such laboratory studies it is convenient to have access to a wide array of logic gates. Here a systematic approach to reduce the logic gate to an NMR pulse sequence is introduced. This approach views the truth table for a quantum logic operation as a permutation matrix that corresponds to a propagator for an NMR transition. This propagator is then used as the starting point for the derivation of a pulse sequence, Pulse sequences for all the permutations of a four level system are reported along with implementations of representative examples on a two spin-1/2 system, C-13-labeled chloroform, (C) 1999 Academic Press. C1 Harvard Univ, MIT, Div Hlth Sci & Technol, Cambridge, MA 02139 USA. Harvard Univ, Sch Med, BCMP, Boston, MA 02115 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. MIT, Dept Nucl Engn, Cambridge, MA 02139 USA. RP Price, MD (reprint author), Harvard Univ, MIT, Div Hlth Sci & Technol, Cambridge, MA 02139 USA. NR 20 TC 28 Z9 29 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1090-7807 J9 J MAGN RESON JI J. Magn. Reson. PD OCT PY 1999 VL 140 IS 2 BP 371 EP 378 DI 10.1006/jmre.1999.1851 PG 8 WC Biochemical Research Methods; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Biochemistry & Molecular Biology; Physics; Spectroscopy GA 243WL UT WOS:000083020400009 PM 10497045 ER PT J AU Rincon, M Roubik, DW Finegan, B Delgado, D Zamora, N AF Rincon, M Roubik, DW Finegan, B Delgado, D Zamora, N TI Understory bees and floral resources in logged and silviculturally treated Costa Rican rainforest plots SO JOURNAL OF THE KANSAS ENTOMOLOGICAL SOCIETY LA English DT Article ID PLANT-POLLINATOR INTERACTIONS; TROPICAL RAIN-FOREST; WET; HYMENOPTERA; DIVERSITY; CANOPY; TREES AB Natural forests managed for timber production conserve tropical biodiversity, but how much? In a lowland wet forest of northeastern Costa Rica, we studied bees and understory flowers in regenerating forest plots logged 6-8 years previously, including silviculturally refined plots where non-timber species were removed. The experiment had a complete randomized block design with 3.24 ha plots (n = 3 per treatment) surrounded by 40 m buffer strips. Our four-month comparative study covered the major flowering period. Overall, 69 species monitored for visitors at 629 individuals demonstrated bees visited and likely pollinated 55 to 80% of understory plants-a mixture of primary forest species in shaded microsites (e.g., palms) and pioneers associated with relatively high insulation (e.g., certain Melastomataceae, Rubiaceae and Solanaceae). Small Halictinae predominated among the bees at flowers, 62% of the 21 species were undescribed. Few notable differences were found among plots of forest drastically altered by culling of non-timber species, and naturally regenerating forest. Such control and refined plots were similar in numbers of species flowering, richness of bees, visitor species per plant, and insolation. Both plot groups had similar complements of halictine species, as well as relatively low levels of foraging specialization by bees evidently nesting, as well as foraging, within plots. Bees were mainly active in shaded microhabitats of closed forest, but the small proportion of relatively insolated plants was heavily visited. Rarity of both native bees frequent in sunny, exposed sites (e.g., Megachile, Centris, Xylocopa) and of African honey bees, is evidence fur existence of both a distinctive guild of understory bees and their perception of conditions in logged forests as similar to those of mature forest. C1 Smithsonian Trop Res Inst, Balboa, Panama. Inst Nacl Biodiversidad, Santo Domingo De Heredia, Costa Rica. Trop Agr Ctr Res & Higher Educ, Turrialba 7170, Costa Rica. RP Rincon, M (reprint author), Univ Autonoma Chiapas, Fac Ciencias Quim, Area Biotecnol, Carretera Puerto Madero Km 2-0, Chiapas 30700, Mexico. NR 44 TC 20 Z9 20 U1 1 U2 8 PU KANSAS ENTOMOLOGICAL SOC PI LAWRENCE PA PO BOX 368, LAWRENCE, KS 66044 USA SN 0022-8567 J9 J KANSAS ENTOMOL SOC JI J. Kans. Entomol. Soc. PD OCT PY 1999 VL 72 IS 4 BP 379 EP 393 PG 15 WC Entomology SC Entomology GA 345MG UT WOS:000088819300003 ER PT J AU Roubik, DW AF Roubik, DW TI The foraging and potential outcrossing pollination ranges of African honey bees (Apiformes : Apidae; Apini) in Congo Forest SO JOURNAL OF THE KANSAS ENTOMOLOGICAL SOCIETY LA English DT Article AB Honey bees (Apis mellifera adansonii) in a Gabonese forest were marked at feeding stations having odor beacons (vanilla extract), offering 4 oz. of 20-50% scented sugar solution. Experiments were conducted for 28 days while 7380 total bees were marked at stations along a 2 km forest trail. Stations each 300 m were used to score honey bee movement to new sites. During 706 station observations, 57% included bees that had shifted feeding sites by up to 1.6 km, with negative logarithmic distribution away from the marking site. Site shifts within a single day showed a similar range, minimum times of 14-18 min for 300-600 m, and a linear relationship between distance and time elapsed since marking (P = 0.001, r(2) = 0.41). These data suggest honey bees may provide gene flow to plant populations within an area of 1.8 km(2) and between individuals separated by >1.5 km. Further analysis suggests bees sometimes trapline 300-600 m, perhaps without first returning to the nest, but rarely do so for longer distances. C1 Smithsonian Trop Res Inst, Balboa, Panama. RP Roubik, DW (reprint author), Smithsonian Trop Res Inst, Apartado 2072, Balboa, Panama. NR 15 TC 7 Z9 7 U1 1 U2 8 PU KANSAS ENTOMOLOGICAL SOC PI LAWRENCE PA PO BOX 368, LAWRENCE, KS 66044 USA SN 0022-8567 J9 J KANSAS ENTOMOL SOC JI J. Kans. Entomol. Soc. PD OCT PY 1999 VL 72 IS 4 BP 394 EP 401 PG 8 WC Entomology SC Entomology GA 345MG UT WOS:000088819300004 ER PT J AU Hershkovitz, MA AF Hershkovitz, MA TI Montia linearis (Douglas) E-Greene (Portulacaceae) in Maryland SO JOURNAL OF THE TORREY BOTANICAL SOCIETY LA English DT Article DE Montia linearis; Portulacaceae; introduced plants; range expansion AB Montia linearis (Portulacaceae), native to the western United States, is reported from a recurring population in Suitland (Prince Georges County), Maryland. The species is now known from four states west of the Mississippi River: Maryland, Massachusetts, Mississippi, and Tennessee. Given this distribution and evidence for weediness in its native range, additional occurrences in the eastern and south-central United States are to be expected. Although it seems likely that Montia linearis has been introduced into the eastern United States via human activity, this cannot be established at present: phylogenetic analyses of Portulacaceae indicate that long-distance dispersal has played a significant role in the biogeographic history of this family. C1 Smithsonian Inst, Lab Mol Systemat, Washington, DC 20560 USA. RP Hershkovitz, MA (reprint author), Smithsonian Inst, Lab Mol Systemat, MSC MRC534, Washington, DC 20560 USA. NR 10 TC 1 Z9 1 U1 1 U2 2 PU TORREY BOTANICAL SOCIETY PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044 USA SN 0040-9618 J9 J TORREY BOT SOC JI J. Torrey Bot. Soc. PD OCT-DEC PY 1999 VL 126 IS 4 BP 350 EP 351 DI 10.2307/2997319 PG 2 WC Plant Sciences SC Plant Sciences GA 250FV UT WOS:000083379100009 ER PT J AU Perry, EA Terhune, JM AF Perry, EA Terhune, JM TI Variation of harp seal (Pagophilus groenlandicus) underwater vocalizations among three breeding locations SO JOURNAL OF ZOOLOGY LA English DT Article DE harp seal; Pagophilus groenlandicus; underwater vocalizations; variation; call type; interbreeding ID SOUND AB We compared the underwater vocalizations of harp seals Pagophilus groenlandicus Erxleben, 1777 recorded during the breeding season at three locations: Jan Mayen Island (north of Iceland); Gulf of St Lawrence; and the 'Front' ice east of Labrador. The three herds shared 17 call types. The Jan Mayen herd had one call type not found in the Gulf or Front. One of the Gulf and Front call types was not found at Jan Mayen. Based on ANOVA post hoc pairwise comparisons between locations, the three herds exhibited a similar number of within-call type differences in duration, number of elements, start pitch and end pitch. There were no differences in proportional usage of call types between the Gulf and Front herds but both differed in a similar manner from those of the Jan Mayen herd. These findings support tagging studies that indicate that the Gulf and Front herds may be interbreeding and both are reproductively isolated from the Jan Mayen herd. We found no evidence of acoustic adaptation to the site-specific ice and environmental conditions associated with the three study locations. C1 Univ New Brunswick, Ctr Coastal Studies & Aquaculture, St John, NB E2L 4L5, Canada. Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Washington, DC 20008 USA. RP Terhune, JM (reprint author), Univ New Brunswick, Ctr Coastal Studies & Aquaculture, POB 5050, St John, NB E2L 4L5, Canada. OI Terhune, John/0000-0002-2661-7389 NR 17 TC 18 Z9 18 U1 1 U2 11 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0952-8369 J9 J ZOOL JI J. Zool. PD OCT PY 1999 VL 249 BP 181 EP 186 DI 10.1111/j.1469-7998.1999.tb00756.x PN 2 PG 6 WC Zoology SC Zoology GA 245QA UT WOS:000083118600007 ER PT J AU Kalfatovic, MR AF Kalfatovic, MR TI William and Henry Walters, the reticent collectors. SO LIBRARY JOURNAL LA English DT Book Review C1 Smithsonian Inst Lib, Washington, DC USA. RP Kalfatovic, MR (reprint author), Smithsonian Inst Lib, Washington, DC USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU BOWKER MAGAZINE GROUP CAHNERS MAGAZINE DIVISION PI NEW YORK PA 249 W 17TH ST, NEW YORK, NY 10011 USA SN 0363-0277 J9 LIBR J JI Libr. J. PD OCT 1 PY 1999 VL 124 IS 16 BP 86 EP 86 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 242HG UT WOS:000082934000044 ER PT J AU Hohn, AA Fernandez, S AF Hohn, AA Fernandez, S TI Biases in dolphin age structure due to age estimation technique SO MARINE MAMMAL SCIENCE LA English DT Article DE age estimation; age structure; lifespan; longevity; tooth preparation techniques; bottlenose dolphin; Tursiops truncatus ID TURSIOPS-TRUNCATUS; GROWTH AB The use of different tooth-preparation techniques resulted in widely different estimates of age in a sample of bottlenose dolphins, Tursiops truncatus. Teeth from 30 animals were prepared using the two-most prevalent techniques reported in the literature for this species, unstained sections and decalcified and stained thin sections, and the resulting paired counts of growth layers were compared. Estimates from the two methods were identical or at least placed the specimen in the same age class in only five cases, ranging in age from 2 to 22 yr. Otherwise, the results fell into one of two categories: when the estimates were close (less than or equal to 3-yr difference, n = 15), counts from unstained sections generally were higher (13 cases, age from unstained sections 2-20 yr); when the counts were more disparate, estimates from stained sections always were higher (6-31 yr difference, n = 10, age from unstained sections 12-27 yr and corresponding ages from stained sections of 27-47). Previous studies of age estimation in known-age bottlenose dolphins indicate that stained sections allow accurate estimates of age and demonstrate that maximum lifespan approaches or exceeds 50 yr. In contrast, the results herein suggest that using unstained sections for age estimation may result in imprecise or biased age-structure data. C1 Natl Marine Fisheries Serv, Off Protected Resources, Silver Spring, MD 20910 USA. Dolphin Biol Res Inst, Marine Mammal Program, Smithsonian Inst, Washington, DC 20560 USA. RP Hohn, AA (reprint author), NOAA, Natl Marine Fisheries Serv, SE Fisheries Sci Ctr, 101 Pivers Isl Rd, Beaufort, NC 28516 USA. RI Hohn, Aleta/G-2888-2011 OI Hohn, Aleta/0000-0002-9992-7062 NR 22 TC 15 Z9 16 U1 0 U2 4 PU SOC MARINE MAMMALOGY PI LAWRENCE PA 1041 NEW HAMPSHIRE ST, LAWRENCE, KS 66044 USA SN 0824-0469 J9 MAR MAMMAL SCI JI Mar. Mamm. Sci. PD OCT PY 1999 VL 15 IS 4 BP 1124 EP 1132 DI 10.1111/j.1748-7692.1999.tb00881.x PG 9 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA 250RP UT WOS:000083402100024 ER PT J AU Sullivan, J Swofford, DL Naylor, GJP AF Sullivan, J Swofford, DL Naylor, GJP TI The effect of taxon sampling on estimating rate heterogeneity parameters of maximum-likelihood models SO MOLECULAR BIOLOGY AND EVOLUTION LA English DT Article DE rate heterogeneity; parameter estimation; maximum likelihood; molecular phylogeny; parametric bootstrap; simulation; stationarity ID SITE RATE VARIATION; DNA-SEQUENCES; NUCLEOTIDE-SEQUENCES; PHYLOGENETIC METHODS; EVOLUTIONARY TREES; SUBSTITUTION RATES; DISTANCES; PARSIMONY AB As maximum-likelihood approaches to the study of molecular systematics and evolution become both more flexible and more accessible, the importance of understanding the statistical properties of parameter estimation becomes critical. Using variation in NADH-2 sequences for 40 species of requiem sharks, we illustrate that estimates of rate heterogeneity parameters are highly sensitive to taxon sampling when the data are best explained by a mixed-distribution model of among-site rate variation (invariable sites plus gamma distribution [I+Gamma]). Using computer simulation, we attempt to differentiate two possible causes of this sensitivity. While the possibility of nonstationarity cannot be definitively rejected, our results suggest that sampling error alone provides an adequate explanation for the pattern of uncertainty observed in estimates from the real data. Furthermore, we illustrate that two parameters estimated under the I+Gamma model (the proportion of sites not free to change and the gamma distribution shape parameter) are highly correlated and that the likelihood surface across the rate heterogeneity parameter space can be poorly behaved when only a small number of sequences (taxa) are considered. C1 Univ Idaho, Dept Sci Biol, Moscow, ID 83844 USA. Iowa State Univ, Dept Zool, Ames, IA 50011 USA. Smithsonian Inst, Lab Mol Systemat, Washington, DC 20560 USA. RP Sullivan, J (reprint author), Univ Idaho, Dept Sci Biol, Moscow, ID 83844 USA. NR 37 TC 112 Z9 113 U1 0 U2 8 PU SOC MOLECULAR BIOLOGY EVOLUTION PI LAWRENCE PA PO BOX 1897, LAWRENCE, KS 66044-8897 USA SN 0737-4038 J9 MOL BIOL EVOL JI Mol. Biol. Evol. PD OCT PY 1999 VL 16 IS 10 BP 1347 EP 1356 PG 10 WC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity GA 246WM UT WOS:000083187900004 ER PT J AU Dick, CW Hamilton, MB AF Dick, CW Hamilton, MB TI Microsatellites from the Amazonian tree Dinizia excelsa (Fabaceae) SO MOLECULAR ECOLOGY LA English DT Article DE Dinizia excelsa; Fabaceae; microsatellite; paternity inference; tropical tree C1 Harvard Univ, Dept Organism & Evolut Biol, Cambridge, MA 02138 USA. Georgetown Univ, Dept Biol, Washington, DC 20057 USA. Natl Inst Res Amazon INPA, Biol Dynam Forest Fragments Project, BR-69011970 Manaus, Amazonas, Brazil. RP Dick, CW (reprint author), Smithsonian Trop Res Inst, Apartado 2072, Balboa, Panama. RI Dick, Christopher/A-8744-2008 NR 8 TC 7 Z9 7 U1 0 U2 1 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0962-1083 J9 MOL ECOL JI Mol. Ecol. PD OCT PY 1999 VL 8 IS 10 BP 1765 EP 1766 DI 10.1046/j.1365-294x.1999.00723-7.x PG 2 WC Biochemistry & Molecular Biology; Ecology; Evolutionary Biology SC Biochemistry & Molecular Biology; Environmental Sciences & Ecology; Evolutionary Biology GA 251VJ UT WOS:000083466800027 PM 10583846 ER PT J AU Tringali, MD Bert, TM Seyoum, S Bermingham, E Bartolacci, D AF Tringali, MD Bert, TM Seyoum, S Bermingham, E Bartolacci, D TI Molecular phylogenetics and ecological diversification of the transisthmian fish genus Centropomus (Perciformes : Centropomidae) SO MOLECULAR PHYLOGENETICS AND EVOLUTION LA English DT Article DE molecular phylogenetics; allozymes; 16S ribosomal RNA; Centropomidae; rate heterogeneity; transisthmian pairs; divergence times; ecological diversification ID MITOCHONDRIAL-DNA EVOLUTION; ELECTROPHORETIC DATA; HAWAIIAN DROSOPHILA; SEQUENCE EVOLUTION; PANAMA; RATES; ISTHMUS; AMPLIFICATION; PROTEIN; TREES AB Phylogenetic relationships among the 12 recognized fish species in the New World genus Centropomus (Pisces, Centropomidae) were analyzed using allozyme electrophoresis and 618 bp of the mitochondrial DNA 16S ribosomal RNA (rRNA) gene. Molecular phylogenetic trees were generally consistent with previously published partial hypotheses based on morphological evidence. However, previously undefined sister group relationships between major species groups were resolved using molecular data, and phylogenetic hypotheses for Centropomus based on 16S rRNA sequences were better supported than were allozyme-based hypotheses. The high level of congruence among the trees inferred from the nuclear and mitochondrial characters provided a firm phylogenetic basis for analysis of ecological diversification and molecular evolution in the genus. Compared to basal Centropomus species, members of the most nested species group were significantly larger in body size and occupied a marine niche only peripherally utilized by their congeners. We also observed substitution rate heterogeneity among 16S rRNA lineages; in contrast to expectations based on "metabolic rate" and "generation interval" models, relative substitution rates were faster than expected for the group of large-bodied snooks. Using the Pliocene rise of the Central American isthmian marine barrier to calibrate rates of 16S ribosomal gene evolution in Centropomus, we found that the rates for the genus were similar to those reported for higher vertebrates. Analysis of the three sets of transisthmian geminate taxa in Centropomus indicated that two of the pairs were probably formed duping the Pliocene rise of the isthmus while the third pair diverged several million years earlier. (C) 1999 Academic Press. C1 Florida Marine Res Inst, Dept Environm Protect, St Petersburg, FL 33701 USA. Smithsonian Trop Res Inst, Balboa, Panama. RP Tringali, MD (reprint author), Florida Marine Res Inst, Dept Environm Protect, 100 8th Ave SE, St Petersburg, FL 33701 USA. NR 79 TC 57 Z9 61 U1 0 U2 5 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1055-7903 J9 MOL PHYLOGENET EVOL JI Mol. Phylogenet. Evol. PD OCT PY 1999 VL 13 IS 1 BP 193 EP 207 DI 10.1006/mpev.1999.0624 PG 15 WC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity GA 245VW UT WOS:000083129700018 PM 10508552 ER PT J AU Glaser, JR AF Glaser, JR TI Basic museum studies SO MUSEUM INTERNATIONAL LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Glaser, JR (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU BLACKWELL PUBL LTD PI OXFORD PA 108 COWLEY RD, OXFORD OX4 1JF, OXON, ENGLAND SN 1350-0775 J9 MUSEUM INT JI Mus. Int. PD OCT-DEC PY 1999 VL 51 IS 4 BP 60 EP 64 PG 5 WC Art SC Art GA 243UQ UT WOS:000083016000012 ER PT J AU Lukin, MD Yelin, SF Fleischhauer, M Scully, MO AF Lukin, MD Yelin, SF Fleischhauer, M Scully, MO TI Quantum interference effects induced by interacting dark resonances SO PHYSICAL REVIEW A LA English DT Article ID ELECTROMAGNETICALLY INDUCED TRANSPARENCY; POPULATION-INVERSION; 3-LEVEL SYSTEMS; LASER; INDEX; REFRACTION; COHERENCE; PULSES; MEDIA; RB AB We predict the possibility of sharp, high-contrast resonances in the optical response of a broad class of systems, wherein interference effects are generated by coherent perturbation or interaction of dark states. The properties of these resonances can be manipulated to design a desired atomic response. [S1050-2947(99)02507-X]. C1 Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. Univ Munich, Sekt Phys, D-80333 Munich, Germany. Max Planck Inst Quantum Opt, D-85748 Garching, Germany. RP Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. RI Fleischhauer, Michael/G-6716-2011 NR 26 TC 255 Z9 267 U1 0 U2 10 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9926 EI 2469-9934 J9 PHYS REV A JI Phys. Rev. A PD OCT PY 1999 VL 60 IS 4 BP 3225 EP 3228 DI 10.1103/PhysRevA.60.3225 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 247BP UT WOS:000083201000083 ER PT J AU Taylor, JM Dalgarno, A Babb, JF AF Taylor, JM Dalgarno, A Babb, JF TI Dipole polarizability of the hydrogen molecular ion SO PHYSICAL REVIEW A LA English DT Article ID RYDBERG STATES; VALUES; H-2; H2+ AB PI procedure is described for the precise nonrelativistic evaluation of the dipole polarizabilities of H-2(+) and D-2(+) that avoids any approximation based on the size of the electron mass relative to the nucleus mass. The procedure is constructed so that sum rules may be used to assess the accuracy of the calculation. The resulting polarizabilities are consistent with experiment within the error bars of the measurements and are far more precise than values obtained by other theoretical methods. [S1050-2947(99)50710-5]. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Taylor, JM (reprint author), Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, 60 Garden St, Cambridge, MA 02138 USA. RI Taylor, Jacob/B-7826-2011 OI Taylor, Jacob/0000-0003-0493-5594 NR 20 TC 20 Z9 20 U1 0 U2 9 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD OCT PY 1999 VL 60 IS 4 BP R2630 EP R2632 DI 10.1103/PhysRevA.60.R2630 PG 3 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 247BP UT WOS:000083201000006 ER PT J AU Flint, OS Bueno-Soria, J AF Flint, OS Bueno-Soria, J TI Studies of neotropical caddisflies LVIII: New species of the genus Ochrotrichia Mosely (Trichoptera : Hydroptilidae) from Peru SO PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON LA English DT Article DE Ochtrotrichia; Trichoptera; Hydroptilidae; caddisfly; new species; Peru ID AQUATIC INSECTS; AMERICA AB Nine new species of the genus Ochrotrichia from Peru are described, diagnosed and figured: O. intortilis, O. obtecta, O. flexura, O. bipartita, O. calcarata, O. hamatilis, O. machiguenga, O. manuensis, and O. campanilla. C1 Natl Museum Nat Hist, Smithsonian Inst, Dept Entomol, Washington, DC 20560 USA. RP Flint, OS (reprint author), Natl Museum Nat Hist, Smithsonian Inst, Dept Entomol, Washington, DC 20560 USA. NR 12 TC 2 Z9 3 U1 0 U2 0 PU ENTOMOL SOC WASHINGTON PI WASHINGTON PA SMITHSONIAN INSTITUTION DEPT ENTOMOLOGY, WASHINGTON, DC 20560 USA SN 0013-8797 J9 P ENTOMOL SOC WASH JI Proc. Entomol. Soc. Wash. PD OCT PY 1999 VL 101 IS 4 BP 729 EP 736 PG 8 WC Entomology SC Entomology GA 246MG UT WOS:000083167100005 ER PT J AU Polhemus, DA AF Polhemus, DA TI A new species of riparian Nabidae (Heteroptera) from the Hawaiian Islands SO PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON LA English DT Article DE Nabidae; riparian; Hawaiian Islands; Maui; Molokai AB A new species of Hawaiian Nabidae. Nabis gagneorum, is described from the islands of Maul and Molokai. This species is unusual among Nabidae in that it occurs in wet riparian habitats within and adjacent to swift streams. Figures of the male and female dorsal habitus and male paramere are provided, accompanied by a distribution map. C1 Natl Museum Nat Hist, Dept Entomol, Smithsonian Inst, MRC 105, Washington, DC 20560 USA. RP Polhemus, DA (reprint author), Natl Museum Nat Hist, Dept Entomol, Smithsonian Inst, MRC 105, Washington, DC 20560 USA. NR 1 TC 5 Z9 5 U1 0 U2 1 PU ENTOMOL SOC WASHINGTON PI WASHINGTON PA SMITHSONIAN INSTITUTION DEPT ENTOMOLOGY, WASHINGTON, DC 20560 USA SN 0013-8797 J9 P ENTOMOL SOC WASH JI Proc. Entomol. Soc. Wash. PD OCT PY 1999 VL 101 IS 4 BP 868 EP 874 PG 7 WC Entomology SC Entomology GA 246MG UT WOS:000083167100018 ER PT J AU Gagne, RJ AF Gagne, RJ TI Obituary - Alan Stone - 1904-1999 SO PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON LA English DT Biographical-Item C1 Agr Res Serv, System Entomol Lab,PSI, USDA, Natl Museum Nat Hist,Smithsonian Inst, Washington, DC 20560 USA. RP Gagne, RJ (reprint author), Agr Res Serv, System Entomol Lab,PSI, USDA, Natl Museum Nat Hist,Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 1 Z9 1 U1 0 U2 1 PU ENTOMOL SOC WASHINGTON PI WASHINGTON PA SMITHSONIAN INSTITUTION DEPT ENTOMOLOGY, WASHINGTON, DC 20560 USA SN 0013-8797 J9 P ENTOMOL SOC WASH JI Proc. Entomol. Soc. Wash. PD OCT PY 1999 VL 101 IS 4 BP 911 EP 913 PG 3 WC Entomology SC Entomology GA 246MG UT WOS:000083167100024 ER PT J AU Catanese, M Weekes, TC AF Catanese, M Weekes, TC TI Very high energy gamma-ray astronomy SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Review ID VERY-HIGH-ENERGY; LACERTAE OBJECT MARKARIAN-421; ACTIVE GALAXY MARKARIAN-421; HIGH-REDSHIFT GALAXIES; SUPERNOVA REMNANT W44; HUBBLE-DEEP-FIELD; X-RAY; CRAB-NEBULA; EGRET OBSERVATIONS; COSMIC-RAYS AB We present a review of the current status of very high energy gamma-ray astronomy. The development of the atmospheric Cerenkov imaging technique for ground-based gamma-ray astronomy has led to a rapid growth in the number of observatories. The detection of TeV gamma-rays from active galactic nuclei was unexpected and is providing new insights into the emission mechanisms in the jets. Next-generation telescopes are under construction and will increase dramatically the knowledge available at this extreme end of the cosmic electromagnetic spectrum. C1 Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Harvard Smithsonian Ctr Astrophys, Fred Lawrence Whipple Observ, Amado, AZ 85645 USA. RP Catanese, M (reprint author), Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. NR 164 TC 111 Z9 113 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6280 EI 1538-3873 J9 PUBL ASTRON SOC PAC JI Publ. Astron. Soc. Pac. PD OCT PY 1999 VL 111 IS 764 BP 1193 EP 1222 DI 10.1086/316435 PG 30 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 248FP UT WOS:000083264700001 ER PT J AU Hershler, R AF Hershler, R TI A systematic review of the hydrobiid snails (Gastropoda : Rissooidea) of the Great Basin, western United States. Part II. Genera Colligyrus, Eremopyrgus, Fluminicola, Pristinicola, and Tryonia SO VELIGER LA English DT Article ID CALIFORNIA; CHECKLIST AB This second and final part of a taxonomic treatment of hydrobiid snails of the Great Basin region in the western United States (based principally on material collected during a recently completed field survey) focuses on fauna other than the genus Pyrgulopsis. A new genus of small amnicoline snails, Colligyrus, is proposed for Hydrobia greggi Pilsbry, 1935, together with a new species from the Harney Lake basin of Oregon. This group is strongly differentiated from other amnicolines by a unique female genitalic groundplan. New records are provided for three species of Fluminicola, and two new congeners are described from the northwest Great Basin, both of which had previously been confused with F. turbiniformis (Tryon, 1865). A new genus of cochliopine snails, Eremopyrgus, is erected for a new species from Steptoe Valley, Nevada. Eremopyrgus is distinguished from other cochliopines by unique aspects of its glandular penial lobes and other genitalic features. New records are provided for two species of Tryonia, and a new congener is described from thermal springs in central Nevada Several new records of Pristinicola hemphilli (Pilsbry, 1890) from the extreme northwest Great Basin are provided. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Intvertebrate Zool Mollusks, Washington, DC 20560 USA. RP Hershler, R (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Intvertebrate Zool Mollusks, NHB STOP 118, Washington, DC 20560 USA. NR 68 TC 20 Z9 22 U1 1 U2 3 PU CALIF MALACOZOOLOGICAL SOC INC PI SANTA BARBARA PA SANTA BARBARA MUSEUM NATURAL HISTORY, 2559 PUESTA DEL SOL RD, SANTA BARBARA, CA 93105 USA SN 0042-3211 J9 VELIGER JI Veliger PD OCT 1 PY 1999 VL 42 IS 4 BP 306 EP 337 PG 32 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA 244FC UT WOS:000083040300002 ER PT J AU Correll, DL Jordan, TE Weller, DE AF Correll, DL Jordan, TE Weller, DE TI Effects of precipitation and air temperature on nitrogen discharges from Rhode River watersheds SO WATER AIR AND SOIL POLLUTION LA English DT Article; Proceedings Paper CT Workshop on Fate of Pesticides in the Atmosphere Implications for Risk Assessment CY APR 22-24, 1998 CL DRIEBERGEN, NETHERLANDS DE ammonium; nitrate nitrogen; organic-N; watershed; weather effects ID COASTAL-PLAIN WATERSHEDS; NUTRIENT DYNAMICS; CHESAPEAKE BAY; NITRATE-NITROGEN; EXPORT; FOREST; TRIBUTARIES; PHOSPHORUS; ESTUARY; ZONE AB We studied discharges of total-N, nitrate, ammonium, and total organic-N from seven contiguous small watersheds on the Atlantic Coastal Plain in Maryland for up to 25 yr. These watersheds have perched aquifers so all groundwater discharges as well as surface runoff were measured at V-notch weirs which included volume-integrating flow-proportional samplers. Interannual variations in annual and seasonal precipitation during this study spanned approximately the range of 160 yr weather records in the region. Annual total-N area yields from the overall watershed varied nine-fold, correlations of all N-parameter discharges with precipitation were highly significant, and power function regressions of precipitation vs N-discharge explained from 36 to 59% of the variance. Nitrogen fluxes from a cropland watershed were much higher and more variable with volume of precipitation, while fluxes from a forested watershed were much lower and were primarily composed of organic-N. Correlations of N-fluxes with precipitation were higher in the winter and spring. Annual and seasonal N-concentrations also often increased significantly with precipitation. Variations in seasonal air temperature sometimes explained significant amounts of variance in N-discharges, especially ammonium. A model composed of regressions was used to construct graphical and tabular summaries. C1 Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. RP Correll, DL (reprint author), Smithsonian Environm Res Ctr, POB 28, Edgewater, MD 21037 USA. OI Weller, Donald/0000-0002-7629-5437 NR 34 TC 9 Z9 9 U1 1 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0049-6979 J9 WATER AIR SOIL POLL JI Water Air Soil Pollut. PD OCT PY 1999 VL 115 IS 1-4 BP 547 EP 575 DI 10.1023/A:1005194630598 PG 29 WC Environmental Sciences; Meteorology & Atmospheric Sciences; Water Resources SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences; Water Resources GA 243XT UT WOS:000083023300030 ER PT J AU Smith, BC AF Smith, BC TI Becoming Americans: Our struggle to be both free and equal SO WILLIAM AND MARY QUARTERLY LA English DT Book Review C1 Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. RP Smith, BC (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU INST EARLY AMER HIST CULT PI WILLIAMSBURG PA BOX 220, WILLIAMSBURG, VA 23187 USA SN 0043-5597 J9 WILLIAM MARY QUART JI William Mary Q. PD OCT PY 1999 VL 56 IS 4 BP 842 EP 847 DI 10.2307/2674249 PG 6 WC History SC History GA 254DJ UT WOS:000083596400019 ER PT J AU de Muizon, C Domning, DP Parrish, M AF de Muizon, C Domning, DP Parrish, M TI Dimorphic tusks and adaptive strategies in a new species of walrus-like dolphin (Odobenocetopsidae) from the Pliocene of Peru SO COMPTES RENDUS DE L ACADEMIE DES SCIENCES SERIE II FASCICULE A-SCIENCES DE LA TERRE ET DES PLANETES LA English DT Article DE Cetacea; Odobenocetopsidae; Pliocene; Peru; feeding strategies; dimorphic tusks AB Three new specimens of the walrus-like dolphin Odobenocetops from the Pliocene of Peru, shed new light on the anatomy and adaptive strategies of this unique Cetacean. Odobenocetops leprodon nov. sp. is represented by a skull, which bears a 135-cm-long needle-like right tusk and a small 25-cm-long left tusk the apex of which was erupted. The long tusk was probably held almost parallel to the axis of the body when swimming. In contrast to O. peruvianus, O. leptodon probably had a small melon and, therefore, echolocation ability, but had reduced (or no) binocular vision. A skull of O. peruvianus with two small tusks similar in size is referred to a female. ((C) Academie des sciences / Elsevier, Paris.). C1 Museum Natl Hist Nat, CNRS, UMR 8569, Lab Paleontol, F-75005 Paris, France. Howard Univ, Dept Anat, Washington, DC 20059 USA. Smithsonian Inst, Natl Museum Amer Hist, Dept Paleobiol, Washington, DC 20560 USA. RP de Muizon, C (reprint author), Museum Natl Hist Nat, CNRS, UMR 8569, Lab Paleontol, 8 Rue Buffon, F-75005 Paris, France. NR 23 TC 7 Z9 8 U1 0 U2 5 PU EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER PI PARIS CEDEX 15 PA 23 RUE LINOIS, 75724 PARIS CEDEX 15, FRANCE SN 1251-8050 J9 CR ACAD SCI II A JI Comptes Rendus Acad. Sci. Ser II-A PD SEP 30 PY 1999 VL 329 IS 6 BP 449 EP 455 DI 10.1016/S1251-8050(00)80070-1 PG 7 WC Geosciences, Multidisciplinary SC Geology GA 245HF UT WOS:000083100200010 ER PT J AU Campbell, BA AF Campbell, BA TI Surface formation rates and impact crater densities on Venus SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID RESURFACING HISTORY; VOLCANISM; PLAINS AB Impact crater density has been used to estimate relative ages of major Venus geologic units, typically based on the assumption of short, globally synchronous formation periods. The total number density of craters is the only parameter which may be quantified for most Venus subregions, in contrast to the size-frequency analysis often used for other planetary studies. This paper examines the statistical limits on such crater counts and the predicted crater density for various possible time-varying surface formation rate functions. These results show that (I) the true mean crater density is poorly constrained due to the limited sample size provided by aggregate geologic unitd, and (2) any given crater density can be accommodated by a very short pulse of unit formation at some age T, Gaussian-distributed formation functions of mean age 2) emission within the velocity range of the EHV CO gas. This emission is roughly compatible with the expected HCO+ emission associated with EHV gas arising from behind dissociative shocks. C1 Univ Illinois, Dept Astron, Urbana, IL 61801 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Barcelona, Dept Astron & Meteorol, E-08028 Barcelona, Spain. Harvey Mudd Coll, Dept Phys, Claremont, CA 91711 USA. RP Girart, JM (reprint author), Univ Illinois, Dept Astron, 1002 W Green St, Urbana, IL 61801 USA. RI Girart, Josep/O-1638-2014 OI Girart, Josep/0000-0002-3829-5591 NR 54 TC 22 Z9 22 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 SEP 10 PY 1999 VL 522 IS 2 BP 921 EP 934 DI 10.1086/307658 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 232FL UT WOS:000082360200027 ER PT J AU Cuntz, M Rammacher, W Ulmschneider, P Musielak, ZE Saar, SH AF Cuntz, M Rammacher, W Ulmschneider, P Musielak, ZE Saar, SH TI Two-component theoretical chromosphere models for K dwarfs of different magnetic activity: Exploring the CaII emission-stellar rotation relationship SO ASTROPHYSICAL JOURNAL LA English DT Article DE line : formation; MHD; stars : activity; stars : chromospheres; stars : late-type; stars : rotation ID MAIN-SEQUENCE STARS; SOLAR-TYPE STARS; CORONAL HEATING MECHANISMS; OPERATOR SPLITTING METHOD; LONGITUDINAL TUBE WAVES; COOL STARS; FLUX TUBES; ACOUSTIC-WAVES; II-H; COMPRESSIBLE CONVECTION AB We compute two-component theoretical chromosphere models for K2 V stars with different levels of magnetic activity. The two components are a nonmagnetic component heated by acoustic waves and a magnetic component heated by longitudinal tube waves. The filling factor for the magnetic component is determined from an observational relationship between the measured magnetic area coverage and the stellar rotation period. We consider stellar rotation periods between 10 and 40 days. We investigate two different geometrical distributions of magnetic flux tubes: uniformly distributed tubes, and tubes arranged as a chromospheric network embedded in the nonmagnetic region. The chromosphere models are constructed by performing state-of-the-art calculations for the generation of acoustic and magnetic energy in stellar convection zones, the propagation and dissipation of this energy at the different atmospheric heights, and the formation of specific chromospheric emission lines that are then compared to the observational data. In all these steps, the two-component structure of stellar photospheres and chromospheres is fully taken into account. We find that heating and chromospheric emission is significantly increased in the magnetic component and is strongest in flux tubes that spread the least with height, expected to occur on rapidly rotating stars with high magnetic filling factors. For stars with very slow rotation, we are able to reproduce the basal pur limit of chromospheric emission previously identified with nonmagnetic regions. Most importantly, however, we find that the relationship between the Ca II H + K emission and the stellar rotation rate deduced from our models is consistent with the relationship given by observations. C1 Univ Alabama, Ctr Space Plasma Aeron & Astrophys Res, Huntsville, AL 35899 USA. Univ Heidelberg, Inst Theoret Astrophys, D-69121 Heidelberg, Germany. Univ Texas, Dept Phys, Arlington, TX 76019 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Cuntz, M (reprint author), Univ Alabama, Ctr Space Plasma Aeron & Astrophys Res, Huntsville, AL 35899 USA. NR 96 TC 51 Z9 51 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 SEP 10 PY 1999 VL 522 IS 2 BP 1053 EP 1068 DI 10.1086/307689 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 232FL UT WOS:000082360200039 ER PT J AU Feldman, U Widing, KG Warren, HP AF Feldman, U Widing, KG Warren, HP TI Morphology of the quiet solar upper atmosphere in the 4 x 10(4) < T-e < 1.4 x 10(6) K temperature regime SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : abundances; Sun : atmosphere; Sun : transition region ID EXTREME-ULTRAVIOLET OBSERVATIONS; TRANSITION REGION; CORONAL HOLES; RAY TELESCOPE; SUN; MODEL; SPECTROMETER; ABUNDANCES; EMISSION; NETWORK AB Studies on the morphology of the solar upper atmosphere began over three decades ago. Early models assumed that the temperature structure of the solar upper atmosphere was continuous with a thin transition region connecting the chromosphere with the corona. Over the years it became apparent that the original depiction of the solar upper atmosphere was too simplistic. In this paper we present a morphological study of the solar upper atmosphere over a wide range of temperatures (4 x 10(4) less than or equal to T-e less than or equal to 1.4 x 10(6) K) using high-resolution images (1 "-2 ") taken by TRACE, the SUMER spectrometer on SOHO, and the NRL spectroheliograph on Skylab. The images dearly show that the 4 x 10(4) less than or equal to T-e less than or equal to 1.4 x 10(6) K temperature domain of the solar upper atmosphere consists of a hierarchy of isothermal loop structures. While at the T-e < 8 x 10(5) K temperature regime the looplike structures are more abundant along the chromospheric network, at higher temperatures (T-e > 9 x 10(5) K) no association between them and the chromospheric network is apparent. The hottest (T-e approximate to 1.4 x 10(6) K), which are also the longest among the quiet-Sun loop structures, form a canopy over the lower temperature loop structures. We discuss in the paper possible relationships between the morphology of the solar upper atmosphere, its elemental abundance, and ideas regarding the origin of the slow-speed solar wind. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. NR 44 TC 89 Z9 89 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 SEP 10 PY 1999 VL 522 IS 2 BP 1133 EP 1147 DI 10.1086/307682 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 232FL UT WOS:000082360200046 ER PT J AU Charbonneau, D Noyes, RW Korzennik, SG Nisenson, P Jha, S Vogt, SS Kibrick, RI AF Charbonneau, D Noyes, RW Korzennik, SG Nisenson, P Jha, S Vogt, SS Kibrick, RI TI An upper limit on the reflected light from the planet orbiting the star tau Bootis SO ASTROPHYSICAL JOURNAL LA English DT Article DE planetary systems; stars : individual (tau Bootis)-; techniques : spectroscopic AB The planet orbiting tau Boo at a separation of 0.046 AU could produce a reflected light flux as bright as 1 x 10(-4) relative to that of the star. A spectrum of the system will contain a reflected light component which varies in amplitude and Doppler shift as the planet orbits the star. Assuming the secondary spectrum is primarily the reflected stellar spectrum, we can limit the relative reflected light flux to be less than 5 x 10(-5). This implies an upper limit of 0.3 for the planetary geometric albedo near 480 nm, assuming a planetary radius of 1.2 R-Jup. This albedo is significantly less than that of any of the giant planets of the solar system and is not consistent with certain published theoretical predictions. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Calif Santa Cruz, Univ Calif Observ, Lick Observ, Santa Cruz, CA 95064 USA. RP Charbonneau, D (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. OI Charbonneau, David/0000-0002-9003-484X NR 20 TC 100 Z9 100 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 SEP 10 PY 1999 VL 522 IS 2 BP L145 EP L148 DI 10.1086/312234 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 232FN UT WOS:000082360400017 ER PT J AU Myers, PC Gammie, CF AF Myers, PC Gammie, CF TI On the turbulent velocity dispersion in molecular clouds SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : clouds; MHD; turbulence ID DENSE CORES; HYDROMAGNETIC-WAVES; STAR-FORMATION; DARK CLOUDS; MILLIMETER; GLOBULES AB We model the "line width-size relation" sigma-L-alpha by averaging a power-law spectrum of turbulent motions over a region of size L. This model reproduces the index alpha = 0-1 of most line width-size relations observed in molecular clouds, provided that L lies within the range of component wavelengths, the turbulent energy spectrum has power-law index p = 1-2, and the spectral components have random relative phases. The relation between p and alpha is independent of the dimensionality of the turbulence. As p increases beyond similar to 3, alpha approaches unity, departing from the value (p - 1)/2 expected in a simpler model, because the velocity profile approaches that of its longest wavelength spectral component. Fixed relative phases, expected for excitation by coherent sources, also yield a power-law line width-size relation but require a much steeper energy spectrum to match observations. If the turbulent spectrum has sharp cutoffs, the slope or changes sharply as L goes beyond the range of component wavelengths, approaching alpha = 1 for L < lambda(min) and alpha = 0 for L > lambda(max), independent of p. These changes in slope are due to simple properties of sinusoids and offer observational signatures of the extreme turbulent wavelengths in a cloud. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Illinois, Dept Astron, Urbana, IL 61801 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. RP Myers, PC (reprint author), Harvard Smithsonian Ctr Astrophys, Mail Stop 42,60 Garden St, Cambridge, MA 02138 USA. NR 37 TC 28 Z9 29 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 SEP 10 PY 1999 VL 522 IS 2 BP L141 EP L144 DI 10.1086/312236 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 232FN UT WOS:000082360400016 ER PT J AU Killingback, T Doebeli, M Knowlton, N AF Killingback, T Doebeli, M Knowlton, N TI Variable investment, the Continuous Prisoner's Dilemma, and the origin of cooperation SO PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES LA English DT Article DE evolution of cooperation; Continuous Prisoner's Dilemma; spatial games; cellular automata; stochastic games ID EVOLUTIONARY GAMES; HYPERCYCLES; CHAOS AB Cooperation is fundamental to many biological systems. A common metaphor for studying the evolution of cooperation is the Prisoner's Dilemma, a game with two strategies: cooperate or defect. However, cooperation is rarely all or nothing, and its evolution probably involves the gradual extension of initially modest degrees of assistance. The inability of the Prisoner's Dilemma to capture this basic aspect limits its use for understanding the evolutionary origins of cooperation. Here we consider a framework for cooperation based on the concept of investment: an act which is costly, but which benefits other individuals, where the cost and benefit depend on the level of investment made. In the resulting Continuous Prisoner's Dilemma the essential problem of cooperation remains: in the absence of any additional structure non-zero levels of investment cannot evolve. However, if investments are considered in a spatially structured context, selfish individuals who make arbitrarily low investments can be invaded by higher-investing mutants. This results in the mean level of investment evolving to significant levels, where it is maintained indefinitely. This approach provides a natural solution to the fundamental problem of how cooperation gradually increases from a non-cooperative state. C1 Univ Basel, Inst Zool, CH-4051 Basel, Switzerland. Smithsonian Trop Res Inst, Balboa, Panama. Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. RP Killingback, T (reprint author), Univ Basel, Inst Zool, Rheinsprung 9, CH-4051 Basel, Switzerland. EM killingback@ubaclu.unibas.ch RI Doebeli, Michael/D-5391-2012 NR 27 TC 128 Z9 129 U1 2 U2 9 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 0962-8452 J9 P ROY SOC B-BIOL SCI JI Proc. R. Soc. B-Biol. Sci. PD SEP 7 PY 1999 VL 266 IS 1430 BP 1723 EP 1728 PG 6 WC Biology; Ecology; Evolutionary Biology SC Life Sciences & Biomedicine - Other Topics; Environmental Sciences & Ecology; Evolutionary Biology GA 241DJ UT WOS:000082866800002 PM 10518320 ER PT J AU Jenke, V AF Jenke, V TI Sacred arts of Haitian Vodou - A curriculum resource unit SO AFRICAN ARTS LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Jenke, V (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 1 U2 1 PU UNIV CALIF PI LOS ANGELES PA AFRICAN STUDIES CNTR, LOS ANGELES, CA 90024 USA SN 0001-9933 J9 AFR ARTS JI Afr. Arts PD FAL PY 1999 VL 32 IS 3 BP 90 EP 91 DI 10.2307/3337720 PG 2 WC Art SC Art GA 258LA UT WOS:000083839600020 ER PT J AU Ambs, SM Boness, DJ Bowen, WD Perry, EA Fleischer, RC AF Ambs, SM Boness, DJ Bowen, WD Perry, EA Fleischer, RC TI Proximate factors associated with high levels of extraconsort fertilization in polygynous grey seals SO ANIMAL BEHAVIOUR LA English DT Article ID NORTHERN ELEPHANT SEALS; EXTRA-PAIR COPULATIONS; MALE MATING SUCCESS; HALICHOERUS-GRYPUS; REPRODUCTIVE SUCCESS; BREEDING-BEHAVIOR; SEXUAL-BEHAVIOR; PURPLE MARTINS; GRAY SEAL; PATERNITY AB Behavioural estimates of male mating success in polygynous grey seals, Halichoerus grypus, may be misleading as females are known to be promiscuous. At Sable island, Nova Scotia, we collected behavioural observations and skin samples for paternity analysis from 56 females and their attending males. Twenty-four of these females were found in the following year and their offspring were sampled. Using seven hypervariable microsatellite loci, we excluded the consort male as the father in 43% of the cases. The probability of exclusion of these seven loci was 98.2%. Contrary to expectations, inland females had higher rates of extraconsort fertilizations (ECFs) (70%) than beach females (23%). Younger females (<9 years) had slightly more ECFs than older females, but this was not significant. The duration of male consortship did not differ between females with ECFs and females fertilized by their consort male. Two explanations may account for the inland females having more ECFs: a higher ratio of females to tenured males inland may provide a greater opportunity for nonconsort males to obtain copulations; and inland females travel greater distances to depart for the ocean and may attract more males. These results are more consistent with the hypothesis that ECFs are a by-product for females of male strategies to maximize reproductive success than with hypotheses concerned with either material or genetic benefits gained by females. (C) 1999 The Association for the Study of Animal Behaviour. C1 Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Washington, DC 20008 USA. George Mason Univ, Dept Biol, Fairfax, VA 22030 USA. Bedford Inst Oceanog, Dept Fisheries & Oceans, Marine Fish Div, Dartmouth, NS, Canada. RP Boness, DJ (reprint author), Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Washington, DC 20008 USA. RI Bowen, William/D-2758-2012 NR 58 TC 27 Z9 27 U1 2 U2 10 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0003-3472 J9 ANIM BEHAV JI Anim. Behav. PD SEP PY 1999 VL 58 BP 527 EP 535 DI 10.1006/anbe.1999.1201 PN 3 PG 9 WC Behavioral Sciences; Zoology SC Behavioral Sciences; Zoology GA 241BY UT WOS:000082863300008 ER PT J AU Beckman, E Applefield, J AF Beckman, E Applefield, J TI The Fluxus reader SO ART JOURNAL LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Beckman, E (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU COLLEGE ART ASSOC PI NEW YORK PA 275 SEVENTH AVE, NEW YORK, NY 10001 USA SN 0004-3249 J9 ART J JI Art J. PD FAL PY 1999 VL 58 IS 3 BP 100 EP 102 DI 10.2307/777864 PG 3 WC Art SC Art GA 249KT UT WOS:000083332800016 ER PT J AU Beckman, E Applefield, J AF Beckman, E Applefield, J TI 'MR. FLUXUS': A collective portrait of George Maciunas, 1931-1978 SO ART JOURNAL LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Beckman, E (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU COLLEGE ART ASSOC PI NEW YORK PA 275 SEVENTH AVE, NEW YORK, NY 10001 USA SN 0004-3249 J9 ART J JI Art J. PD FAL PY 1999 VL 58 IS 3 BP 100 EP 102 DI 10.2307/777864 PG 3 WC Art SC Art GA 249KT UT WOS:000083332800015 ER PT J AU Beckman, E Applefield, J AF Beckman, E Applefield, J TI Off limits: Rutgers University and the avant-garde, 1957-1963 SO ART JOURNAL LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Beckman, E (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU COLLEGE ART ASSOC PI NEW YORK PA 275 SEVENTH AVE, NEW YORK, NY 10001 USA SN 0004-3249 J9 ART J JI Art J. PD FAL PY 1999 VL 58 IS 3 BP 100 EP 102 DI 10.2307/777864 PG 3 WC Art SC Art GA 249KT UT WOS:000083332800014 ER PT J AU Sonnenborn, DA AF Sonnenborn, DA TI The music of Arab-Americans: A retrospective collection - Rounder CD-1122 (Anne K. Rasmussen) SO ASIAN MUSIC LA English DT Record Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Sonnenborn, DA (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU SOC ASIAN MUSIC DEPT ASIAN STUDIES PI ITHACA PA 338 ROCKEFELLER HALL CORNELL UNIV, ITHACA, NY 14853 USA SN 0044-9202 J9 ASIAN MUSIC JI Asian Music PD FAL-WIN PY 1999 VL 31 IS 1 BP 187 EP 188 DI 10.2307/834284 PG 2 WC Asian Studies; Music SC Asian Studies; Music GA 274HN UT WOS:000084760500008 ER PT J AU Caldwell, N AF Caldwell, N TI Surface brightness profiles of three new dwarf spheroidal companions to M31 SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : dwarf; galaxies : elliptical and lenticular, cD; galaxies : structure; Local Group ID STELLAR POPULATIONS; OXYGEN ABUNDANCES; SATELLITE GALAXY; LOCAL GROUP; MAPS AB CCD images of three newly discovered dwarf spheroidal companions to M31, Andromeda V, VI, and VII, are used to extract surface brightness profiles and total magnitudes. Using distance moduli provided by Armandroff et al. and Grebel & Guhathakurta, these galaxies are shown to have similar luminosities to other Local Group dwarf spheroidals; And V in particular is similar to Draco and Ursa Minor in luminosity, i.e., among the faintest known. In the luminosity-metallicity relation, And V is shown to have a significantly higher metallicity than expected. C1 Smithsonian Inst, FL Whipple Observ, Amado, AZ 85645 USA. RP Caldwell, N (reprint author), Smithsonian Inst, FL Whipple Observ, Box 97, Amado, AZ 85645 USA. NR 27 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 0004-6256 J9 ASTRON J JI Astron. J. PD SEP PY 1999 VL 118 IS 3 BP 1230 EP 1234 DI 10.1086/301020 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 241ZR UT WOS:000082914200010 ER PT J AU Briceno, C Calvet, N Kenyon, S Hartmann, L AF Briceno, C Calvet, N Kenyon, S Hartmann, L TI A large-scale objective-prism and X-ray survey in Taurus-Auriga SO ASTRONOMICAL JOURNAL LA English DT Article DE stars : pre-main-sequence; X-rays ID MAIN-SEQUENCE STARS; MOLECULAR CLOUD; DARK CLOUDS; EXTINCTION LAW; DENSE CORES; ROSAT; IRAS; POPULATION; PLEIADES; PERSEUS AB We present the results of a moderately deep, wide-held optical/X-ray survey extending over similar to 60 degrees in the Taurus-Auriga molecular cloud complex. Our observations are sensitive enough to allow us to detect lower mass and older pre-main-sequence stars that could have been missed in previous surveys. We identify four new T Tauri stars, two in the area of L1500 and L1503, one in L1538, and one in L1544. X-rays were detected from three near-IR sources, one of them a very reddened Class II T Tauri star. Four X-ray sources have no known optical/R known counterpart; they could be very reddened premain-sequence stars. Our findings are consistent with the idea that little (if any) star formation has taken place in L1537 and L1538. Although we found one slightly older T Tauri star (similar to 3-4 Myr old), our survey yields no evidence for any significant number of T Tauri stars, regardless of mass and age, outside the main groups of young stars in Taurus. We conclude that the M stars comprising the low-mass end of the ROSAT All-Sky Survey (RASS) source population must be older than similar to 10 Myr and most probably unrelated to the ongoing process of star formation in Taurus. Instead, the bulk of the RASS sources seen toward regions like Taurus seem to trace the history of star formation over a longer period in the solar vicinity. C1 CIDA, Merida, Venezuela. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Briceno, C (reprint author), Yale Univ, Dept Phys, POB 208121, New Haven, CT 06520 USA. EM briceno@hepvms.physics.yale.edu OI Kenyon, Scott/0000-0003-0214-609X NR 72 TC 43 Z9 43 U1 0 U2 0 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 SEP PY 1999 VL 118 IS 3 BP 1354 EP 1368 DI 10.1086/300997 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 241ZR UT WOS:000082914200021 ER PT J AU Garcia, MR Callanan, PJ AF Garcia, MR Callanan, PJ TI Two neutron star soft X-ray transients in quiescence: 4U 2129+47 and EXO 0748-676 SO ASTRONOMICAL JOURNAL LA English DT Article DE binaries : close; stars : individual (4U 2129+47=V1727 Cygni, EXO 0748-676); stars : neutron; X-rays ID CENTAURUS X-4; ROSAT OBSERVATIONS; CYGNI; MODEL; CORONAE AB We report on X-ray observations of two soft X-ray transients containing neutron stars, 4U 2129+47 and EXO O748-616. Our emphasis is on the quiescent properties of these sources. The X-ray spectrum and light curve of the eclipsing low-mass X-ray binary (LMXB) 4U 2129+47 was measured with the ROSAT Position Sensitive Proportinal counter during its current quiescent state. The quiescent X-ray luminosity of similar to 10(32.7) ergs s(-1) and blackbody temperature kT similar to 0.21 keV are similar to other quiescent LMXBs. The quiescent X-ray light curve may show orbital modulation, but the statistics are insufficient to distinguish between a V-shaped partial eclipse(as seen in the high state) or a total square-wave eclipse. The similarity in the luminosity and temperature to other (noneclipsing) quiescent LMXBs implies that the vertical structure in the disk that blocked our direct view of the neutron star in the high state has collapsed, and the neutron star is seen directly. EXO 0748-676 was serendipitously observed with the Einstein IPC in quiescence before it was discovered as a bright transient with EXOSAT. Our reanalysis of this quiescent observation finds L-x similar to 10(34.0) ergs s(-1), and blackbody temperature kT similar to 0.22 keV, again similar to other LMXBs in quiescence. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Coll, Dept Phys, Cork, Ireland. RP Garcia, MR (reprint author), Harvard Smithsonian Ctr Astrophys, MS-4,60 Garden St, Cambridge, MA 02138 USA. NR 36 TC 21 Z9 21 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 SEP PY 1999 VL 118 IS 3 BP 1390 EP 1394 DI 10.1086/301014 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 241ZR UT WOS:000082914200024 ER PT J AU Komossa, S Bohringer, H Huchra, JP AF Komossa, S Bohringer, H Huchra, JP TI X-ray properties of LINERs SO ASTRONOMY & ASTROPHYSICS LA English DT Review DE galaxies : active; galaxies : fundamental parameters; galaxies : ISM; galaxies : nuclei; X-rays : galaxies ID EARLY-TYPE GALAXIES; ADVECTION-DOMINATED ACCRETION; MOLECULAR CLOUD CONTENT; ACTIVE GALACTIC NUCLEI; ULTRAVIOLET EMISSION; SPECTROSCOPIC SURVEY; ELLIPTIC GALAXIES; SEYFERT-GALAXIES; RADIO-SOURCES; H-I AB We present an investigation of the X-ray properties of 13 LINERs based on ROSAT all-sky survey and pointed PSPC and HRI observations. Several sources are studied for the first time in X-rays. The X-ray spectra are best described by a powerlaw with photon index Gamma(X) approximate to -2.0 or thermal emission from gas with very subsolar abundances. The luminosities range between log L(x) = 37.7 (NGC404) and 40.8 (NGC4450). No X-ray variability on the timescale of hours/days is detected. This is in line with the suggestion that LINERs may accrete in the advection-dominated mode. On a longer term, one of the objects, NGC 2768, turns out to be slightly variable. Some sources appear to be extended at weak emission levels whereas the bulk of the X-ray emission is consistent with arising from a point source within the PSPC instrumental resolution. L(X)/L(B) ratios are derived and emission mechanisms that potentially contribute to the observed X-ray luminosities are discussed. We also examine the presence of second X-ray sources near the target sources both in terms of instrumental effects and in terms of 'real' sources within the LINER galaxies. C1 Max Planck Inst Extraterr Phys, D-85740 Garching, Germany. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Komossa, S (reprint author), Max Planck Inst Extraterr Phys, Postfach 1603, D-85740 Garching, Germany. EM skomossa@xray.mpe.mpg.de NR 109 TC 30 Z9 30 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 SEP PY 1999 VL 349 IS 1 BP 88 EP 96 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 241YY UT WOS:000082912500018 ER PT J AU Dobrzycki, A Engels, D Hagen, HJ AF Dobrzycki, A Engels, D Hagen, HJ TI HS 1603+3820: a bright z(em)=2.51 quasar with a very rich heavy element absorption spectrum SO ASTRONOMY & ASTROPHYSICS LA English DT Letter DE galaxies : intergalactic medium; galaxies : quasars : absorption lines; galaxies : quasars : individual : HS 1603+3820 ID LINE SYSTEMS AB During the course of Hamburg/CfA Bright Quasar Survey we discovered a bright (B = 15.9), high redshift(z(em) = 2.51) quasar HS 1603+3820. The quasar has a rich complex of Cry absorbers, containing at least five systems, all within 3000 kms(-1) from one another. Despite large ejection velocity (upsilon(ej) > 5000 km s(-1) for all components) the complex is likely to be associated with the quasar. There are at least three more associated heavy element absorbers, two of which have z(abs) > z(em). Together, they make one of the richest known complexes of associated heavy element absorbers, and the richest in objects with B < 16. The combination of redshift, brightness, richness of the metal absorption spectrum and richness of the associated absorption is unmatched among known quasars. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Hamburger Sternwarte, D-21029 Hamburg, Germany. RP Dobrzycki, A (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM adobrzycki@cfa.harvard.edu; dengels@hs.uni-hamburg.de; hhagen@hs.uni-hamburg.de NR 17 TC 12 Z9 12 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 SEP PY 1999 VL 349 IS 1 BP L29 EP L33 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 241YY UT WOS:000082912500008 ER PT J AU Piraino, S Santangelo, A Ford, EC Kaaret, P AF Piraino, S Santangelo, A Ford, EC Kaaret, P TI BeppoSAX observations of the atoll X-ray binary 4U 0614+091 SO ASTRONOMY & ASTROPHYSICS LA English DT Letter DE accretion, accretion disks; stars : individual : 4U 0614+091; stars : neutron; X-rays : stars ID ACTIVE GALACTIC NUCLEI; BURSTER 4U-0614+091; ACCRETION DISK; EMISSION; SPECTRA; COMPTONIZATION; REFLECTION AB We report the first simultaneous measurement of the broad band X-ray (0.3-150 keV) spectrum of the neutron star xray binary 4U 0614+091. Our data confirm the presence of a hard x-ray tail that can be modeled as thermal Comptonization of low-energy photons on electrons having a very high temperature, greater than 220 keV, or as a non-thermal powerlaw. We detected a spectral feature that can be interpreted as reprocessing, via Compton reflection, of the direct emission by an optically-thick disk and found a correlation between the photon index of the power-law tail and the fraction of radiation reflected which is similar to the correlation found for black hole candidate x-ray binaries and Seyfert galaxies. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CNR, IFCAI, I-90146 Palermo, Italy. Dipartimento Sci Fisiche & Astron, I-90123 Palermo, Italy. Univ Amsterdam, NL-1098 SJ Amsterdam, Netherlands. RP Kaaret, P (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM pkaaret@cfa.harvard.edu NR 33 TC 48 Z9 48 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 SEP PY 1999 VL 349 IS 3 BP L77 EP L80 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 245CK UT WOS:000083088500005 ER PT J AU Young, K Cox, P Huggins, PJ Forveille, T Bachiller, R AF Young, K Cox, P Huggins, PJ Forveille, T Bachiller, R TI The molecular envelope of the Helix Nebula SO ASTROPHYSICAL JOURNAL LA English DT Article DE planetary nebulae : individual (NGC 7293); radio lines : stars; stars : AGB and post-AGB; stars : mass loss ID EVOLVED PLANETARY-NEBULAE; COMETARY KNOTS; CO ENVELOPES; GLOBULES; KJPN-8; DISK; SPECTROSCOPY; EMISSION; NGC-7293; BIPOLAR AB We present a fully sampled map of the Helix Nebula in the 1.3 mm CO J = 2-1 line, made using the Caltech Submillimeter Observatory. The angular resolution is 31 ", and the velocity resolution is 1.5 km s(-1). The CO emission is found to extend over a region similar to 1000 " x 800 " and delineates the well-known double ring or "helix" seen in optical images of the ionized gas. Our observations provide the first complete view of the global kinematics of the envelope and reveal the three-dimensional structure of the gas. The helix is seen to be an expanding, equatorial ring around the ionized nebula, with arcs extending to higher latitudes and exhibiting remarkable point symmetries about the central star. The molecular gas is fragmented into many small condensations with narrow line widths (similar to 1 km s(-1)). The close relationship found between the structure of the envelope and the ionized nebula underscores the important role of neutral gas in determining the morphology of planetary nebulae. The point symmetries provide evidence for early shaping of the envelope by bipolar outflows or jets. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Univ Paris 11, Inst Astrophys Spatiale, F-91405 Orsay, France. NYU, Dept Phys, New York, NY 10003 USA. Observ Grenoble, F-38041 Grenoble, France. IGN, Observ Astron Nacl, Alcala De Henares 28800, Spain. RP Young, K (reprint author), Smithsonian Astrophys Observ, 60 Garden St,MS 78, Cambridge, MA 02138 USA. NR 30 TC 49 Z9 49 U1 1 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 SEP 1 PY 1999 VL 522 IS 1 BP 387 EP 396 DI 10.1086/307639 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 228HJ UT WOS:000082130800031 ER PT J AU Remillard, RA Morgan, EH McClintock, JE Bailyn, CD Orosz, JA AF Remillard, RA Morgan, EH McClintock, JE Bailyn, CD Orosz, JA TI RXTE observations of 0.1-300 Hz quasi-periodic oscillations in the microquasar GRO J1655-40 SO ASTROPHYSICAL JOURNAL LA English DT Article DE black hole physics; stars : individual (GRO J1655-40); stars : oscillations; X-rays : stars ID ACCRETION DISKS; SUPERLUMINAL SOURCE; GRS-1915+105; EMISSION; INSTABILITIES; VARIABILITY; BINARIES AB We have investigated 52 Rossi X-Ray Timing Explorer pointed observations of GRO J1655-40 spanning the X-ray outburst that commenced on 1996 April 25 and lasted for 16 months. Our X-ray timing analyses reveal four types of quasi-periodic oscillations (QPOs): three with relatively stable central frequencies near 300, 9, and 0.1 Hz, and a fourth QPO that varied over the range 14-28 Hz. The 300 and 0.1 Hz QPOs appear only when the power-law component dominates the X-ray spectrum and the estimated unabsorbed X-ray luminosity is above similar to 0.2L(Edd). At lower luminosity (L-X similar to 0.1L(Edd)), the thermal component dominates the spectrum; the disk appears somewhat cooler (similar to 1.3 keV), and its inner radius appears larger. In this state only two of the QPOs are observed: the broad and spectrally "soft" 9 Hz QPO and the narrow, "hard" QPO that varies from 14 to 28 Hz as the hard flux decreases. At still lower luminosities (L-X < 0.1L(Edd)), the power-law component contributes less than 30% of the total luminosity, the inner disk appears both larger and cooler, the 9 Hz QPO vanishes, and only a very weak (rms 0.3%) and narrow QPO at 28 Hz remains. The 300 Hz QPO is likely to be analogous to the stationary QPO at 67 Hz seen in the microquasar GRS 1915+105. We discuss four models of these high-frequency QPOs that depend on effects due to general relativity. The models suggest that these rapid QPOs may eventually provide a measure of the mass and rotation of the accreting black hole. The 9 Hz QPO displays a spectrum consistent with a thermal origin, but this frequency is not uniquely consistent with any of the natural timescales associated with the disk. The mechanism for the 14-28 Hz QPOs appears to be linked to the power-law component, similar to the 1-10 Hz QPOs in GRS 1915+105. Thus these low-frequency QPOs have the potential to lead us to the origin of the energetic electrons that radiate the power-law spectral component. Finally, we show data for GRO J1655-30 and GRS 1915+105 as each source teeters between relative stability and a state of intense oscillations at 0.1 Hz. A comparison of the respective spectral parameters allows us to speculate that the black hole mass in GRS 1915+105 is very large, possibly similar to 100 M.. C1 MIT, Ctr Space Res, Cambridge, MA 02139 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Yale Univ, Dept Astron, New Haven, CT 06520 USA. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. RP Remillard, RA (reprint author), MIT, Ctr Space Res, Room 37-595, Cambridge, MA 02139 USA. NR 52 TC 129 Z9 129 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 SEP 1 PY 1999 VL 522 IS 1 BP 397 EP 412 DI 10.1086/307606 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 228HJ UT WOS:000082130800032 ER PT J AU Gammie, CF AF Gammie, CF TI Efficiency of magnetized thin accretion disks in the Kerr metric SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; black hole physics ID BLACK-HOLES; EXTRACTION; ENERGY; FLOWS AB The efficiency of thin disk accretion onto black holes depends on the inner boundary condition, specifically the torque applied to the disk at the last stable orbit. This is usually assumed to vanish. I estimate the torque on a magnetized disk using a steady magnetohydrodynamic inflow model originally developed by Takahashi et al. I find that the efficiency epsilon can depart significantly from the classical thin disk value. In some cases epsilon>1, i.e., energy is extracted from the black hole. C1 Univ Illinois, Dept Astron, Urbana, IL 61801 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Gammie, CF (reprint author), Univ Illinois, Dept Astron, 1002 W Green St, Urbana, IL 61801 USA. EM gammie@uiuc.edu OI Gammie, Charles /0000-0001-7451-8935 NR 20 TC 138 Z9 138 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD SEP 1 PY 1999 VL 522 IS 1 BP L57 EP L60 DI 10.1086/312207 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 228HL UT WOS:000082131000014 ER PT J AU Markevitch, M AF Markevitch, M TI A differential X-ray Gunn-Peterson test using a giant cluster filament SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology : observations; intergalactic medium ID LY-ALPHA FOREST; INTERGALACTIC MEDIUM; ATOMIC DATA; GALAXIES; NUCLEOSYNTHESIS; ABUNDANCES; OPACITY; IONS; GAS AB Using CCD detectors on board the forthcoming Chandra X-Ray Observatory and X-Ray Multimirror Mission, it is possible to devise a measurement of the absolute density of heavy elements in the hypothetical warm gas that is filling intercluster space. This gas may be the largest reservoir of baryonic matter in the universe, but even its existence has not been proved observationally at low redshifts. The proposed measurement would make use of a unique filament of galaxy clusters spanning over 700 h(50)(-1) Mpc (0.1 less than or similar to z less than or similar to 0.2) along the line of sight in a small area of the sky in Aquarius. The surface density of Abell clusters there is more than 6 times the sky average. It is likely that the intercluster matter column density is enhanced by a similar factor, making its detection feasible under certain optimistic assumptions about its density and elemental abundances. One can compare photoabsorption depth, mostly in the partially ionized oxygen edges, in the spectra of clusters at different distances along the filament, looking for a systematic increase of depth with the distance. The absorption can be measured by the same detector and through the same Galactic column, hence the differential test. A CCD moderate-energy resolution (Delta E similar to 100 eV) is adequate for detecting an absorption edge at a known redshift. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Markevitch, M (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 34 TC 7 Z9 7 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 SEP 1 PY 1999 VL 522 IS 1 BP L13 EP L16 DI 10.1086/312217 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 228HL UT WOS:000082131000004 ER PT J AU Navascues, DB Stauffer, JR Patten, BM AF Navascues, DB Stauffer, JR Patten, BM TI The lithium-depletion boundary and the age of the young open cluster IC 2391 SO ASTROPHYSICAL JOURNAL LA English DT Article DE open clusters and associations : individual (IC 2391); stars : low-mass, brown dwarfs ID BROWN DWARF CANDIDATES; MAIN-SEQUENCE STARS; H-ALPHA EMISSION; LOW-MASS STARS; PLEIADES; SPECTROSCOPY; EVOLUTION AB In previous programs, we have identified a large number of possible, very low mass members of the young open cluster IC 2391 based on their location in an I versus (R-I)(c) color-magnitude diagram. We have now obtained new photometry and intermediate-resolution (Delta lambda = 2.7 Angstrom) spectra of 19 of these objects (14.9 less than or equal to I-c less than or equal to 17.5) in order to confirm cluster membership. We identify 15 of our targets as likely cluster members based on their VRI photometry, spectral types, radial velocity, and H alpha emission strengths. Higher signal-to-noise ratio spectra were obtained for eight of these probable cluster members in order to measure the strength of the doublet Li lambda 6708 and thus obtain an estimate of the cluster's age. One of these eight stars has a definite lithium detection, and two other (fainter) stars have possible lithium detections. A color-magnitude diagram for our program objects shows that the lithium-depletion boundary in IC 2391 is at I-c = 16.2. Using recent theoretical model predictions, we derive an age for IC 2391 of 53 +/- 5 Myr. While this is considerably older than the age most commonly attributed to this cluster (similar to 35 Myr), this result for IC 2391 is comparable to those recently derived for the Pleiades and alpha Persei clusters and can be explained by new models for high-mass stars that incorporate a modest amount of convective-core overshooting. C1 Max Planck Inst Astron, D-69117 Heidelberg, Germany. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Navascues, DB (reprint author), Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany. RI Barrado Navascues, David/C-1439-2017 OI Barrado Navascues, David/0000-0002-5971-9242 NR 32 TC 48 Z9 48 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 SEP 1 PY 1999 VL 522 IS 1 BP L53 EP L56 DI 10.1086/312212 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 228HL UT WOS:000082131000013 ER PT J AU Stanek, KZ Garnavich, PM Kaluzny, J Pych, W Thompson, I AF Stanek, KZ Garnavich, PM Kaluzny, J Pych, W Thompson, I TI BVRI observations of the optical afterglow of GRB 990510 SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts ID DETACHED ECLIPSING BINARIES; GAMMA-RAY BURST; DIRECT DISTANCES; VARIABLES; CEPHEIDS; EMISSION AB We present BVRI observations of the optical counterpart to GRB 990510 obtained with the Las Campanas 1.0 m telescope between 15 and 48 hr after the burst. The temporal analysis of the data indicates steepening decay, independent of wavelength, approaching asymptotically t(-0.76+/-0.01) at early times (t much less than 1 day) and t(-2.40+/-0.02) at late times, with the break time at t(0) = 1.57 +/- 0.03 days. GRB 990510 is the most rapidly fading of the well-documented gamma-ray burst (GRB) afterglows. It is also the first well-observed example of a broadband break for a GRB optical counterpart. The optical spectral energy distribution, corrected for significant Galactic reddening, is well fitted by a single power law with nu(-0.61+/-0.12). However, when the B-band point is dropped from the fit, the power law becomes nu(-0.46+/-0.08), indicating a possible deviation from the power law in the spectrum, either intrinsic or due to additional extinction near the source or from an intervening galaxy at z = 1.62, Broadband break behavior broadly similar to that observed in GRB 990510 has been predicted in some jet models of GRB afterglows, thus supporting the idea that the GRB energy is beamed, at least in some cases. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Warsaw Univ Observ, PL-00478 Warsaw, Poland. Carnegie Inst Washington Observ, Pasadena, CA 91101 USA. N Copernicus Astron Ctr, PL-00716 Warsaw, Poland. RP Stanek, KZ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS20, Cambridge, MA 02138 USA. NR 40 TC 185 Z9 186 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 SEP 1 PY 1999 VL 522 IS 1 BP L39 EP L42 DI 10.1086/312219 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 228HL UT WOS:000082131000010 ER PT J AU Pahre, MA AF Pahre, MA TI Near-infrared imaging of early-type galaxies. II. Global photometric parameters SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE galaxies : elliptical and lenticular, cD; galaxies : fundamental parameters galaxies : photometry; galaxies : stellar content; infrared : galaxies ID SURFACE-BRIGHTNESS FLUCTUATIONS; COMPOSITE STELLAR-SYSTEMS; COLOR MAGNITUDE RELATION; ELLIPTICAL GALAXIES; FUNDAMENTAL PLANE; VELOCITY DISPERSIONS; VIRGO CLUSTER; COMA CLUSTER; PRECISION PHOTOMETRY; SAMPLE SELECTION AB An imaging survey of 341 nearby early-type galaxies in the near-infrared K-band atmospheric window (2.2 mu m) is described. The galaxies primarily reside in 13 nearby rich clusters (85%), while some additional galaxies are drawn from loose groups (12%) and the general held (3%). Surface photometry was measured for the entire sample. Detailed corrections were derived from an extensive grid of seeing-convolved r(1/4) models and then applied to the isophotal surface brightness, aperture magnitude, and ellipticity profiles. Global photometric parameters were derived from this seeing-corrected photometry. More than 25% of the sample has been observed at least twice, and these repeat measurements demonstrate the small internal uncertainties on the derived global photometric parameters. Extensive comparisons with aperture photometry from the literature demonstrate that the photometric system is fully consistent with other photometric systems to less than or equal to 0.01 mag and confirm the estimates of internal random uncertainties. Additional global parameters are drawn from the literature in a homogeneous manner in order to construct a large catalog of galaxy properties: 95% of the galaxies have a velocity dispersion, 69% have a Mg-2 index, 80% have an optical r(eff) and (eff), 82% have a D-n, and 81% have a derived optical - infrared color measurement. This large data set provides excellent source material for investigations of the physical origins of the global scaling relations of early-type galaxies, velocity fields in the local universe, and comparisons to higher redshift early-type galaxies. RP Pahre, MA (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS 20, Cambridge, MA 02138 USA. NR 72 TC 69 Z9 69 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD SEP PY 1999 VL 124 IS 1 BP 127 EP 169 DI 10.1086/313249 PG 43 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 243BQ UT WOS:000082977600005 ER PT J AU Hora, JL Latter, WB Deutsch, LK AF Hora, JL Latter, WB Deutsch, LK TI Investigating the near-infrared properties of planetary nebulae. II. Medium-resolution spectra SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Review DE infrared : ISM : continuum; infrared : ISM : lines and bands; ISM : molecules; ISM : structure; molecular processes; planetary nebulae : general ID MOLECULAR-HYDROGEN EMISSION; HUBBLE-SPACE-TELESCOPE; NARROW-BAND IMAGES; BIPOLAR NEBULAE; RED-RECTANGLE; MASS-LOSS; IRAS 21282+5050; BD +30-DEGREES-3639; CIRCUMSTELLAR ENVELOPES; PROTOPLANETARY NEBULAE AB We present medium-resolution (R similar to 700) near-infrared (lambda = 1-2.5 mu m) spectra of a sample of planetary nebulae (PNe). A narrow slit was used which sampled discrete locations within the nebulae; observations were obtained at one or more positions in the 41 objects included in the survey. The PN spectra fall into one of four general categories: H I emission line-dominated PNe, H I and H-2 emission line PNe, H-2 emission line-dominated PNe, and continuum-dominated PNe. These categories correlate with morphological type, with the elliptical PNe falling into the first group, and the bipolar PNe primarily in the H, and continuum emission groups. The categories also correlate with C/O ratio, with the O-rich objects generally falling into the first group and the C-rich objects in the other groups. Other spectral features were observed in all categories, such as continuum emission from the central star, C-2, CN, and CO emission, and warm dust continuum emission toward the long wavelength end of the spectra. Molecular hydrogen was detected for the first time in four PNe. An excitation analysis was performed using the H-2 line ratios for all of the PN spectra in the survey where a sufficient number of lines were observed. From the near-infrared spectrum, we determined an ortho-to-para ratio, the rotational and vibrational excitation temperatures, and the dominant excitation mechanism of the H-2 for many objects surveyed. One unexpected result from this analysis is that the H-2 is excited by absorption of ultraviolet photons in most of the PNe surveyed, although for several PNe in our survey collisional excitation in moderate velocity shocks plays an important role. The correlation between bipolar morphology and H-2 emission has been strengthened with the new detections of H-2 in this survey. We discuss the role of winds and photons to the excitation of H-2 in PNe, and consider some implications to the utility of H-2 as a nebular diagnostic and to our understanding of PNe structure and evolution. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CALTECH, Ctr Infrared Proc & Anal, SIRTF Sci Ctr, Pasadena, CA 91125 USA. Boston Univ, Dept Astron, Boston, MA 02215 USA. RP Hora, JL (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St MS-65, Cambridge, MA 02138 USA. OI Hora, Joseph/0000-0002-5599-4650 NR 132 TC 79 Z9 79 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD SEP PY 1999 VL 124 IS 1 BP 195 EP 240 DI 10.1086/313256 PG 46 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 243BQ UT WOS:000082977600008 ER PT J AU Hamilton, MB Pincus, EL Di Fiore, A Fleischer, RC AF Hamilton, MB Pincus, EL Di Fiore, A Fleischer, RC TI Universal linker and ligation procedures for construction of genomic DNA libraries enriched for microsatellites SO BIOTECHNIQUES LA English DT Article ID HYBRIDIZATION SELECTION AB Microsatellite loci are highly informative genetic markers useful for population genetic studies,linkage mapping and parentage determination. Methods to identify novel microsatellite loci commonly use subtractive hybridization to enrich small-insert genomic libraries for repeat sequences. A critical step in enrichment is attachment of an oligonucleotide linker,to genomic DNA fragments so that repeat-containing sequences can be recovered by PCR for cloning. Current linkers and ligation methods rely on single restriction enzymes to size-fraction genomic DNA and generate complementary ends. These restriction enzyme/linker combinations ave often species-specific, give poor recovery of repeat-enriched DNA and yield library inserts that are not a broad sample of the genome. We have developed a blunt-end linker; named SNX for its restriction sites, that allows the use of combinations of restriction enzymes to digest the majority of genomic DNA into the 200-1000-bp range. SNX is attached to genomic DNA with a simultaneous ligation/restriction reaction that is highly efficient and improves recovery of sequences after subtractive hybridization. SNX can be used for microsatellite enrichment in any species, since ligation is independent of the restriction enzymes used to size-fraction genomic DNA. These methods improve current repeat-enrichment strategies, resulting in representative small-insert libraries with a very high proportion of positive clones. C1 Georgetown Univ, Dept Biol, Washington, DC 20057 USA. Univ Maryland, College Pk, MD 20742 USA. Smithsonian Inst, Natl Zool Pk, Washington, DC 20008 USA. RP Hamilton, MB (reprint author), Georgetown Univ, Dept Biol, Reiss Sci Bldg 406, Washington, DC 20057 USA. NR 11 TC 636 Z9 654 U1 1 U2 24 PU EATON PUBLISHING CO PI NATICK PA 154 E. CENTRAL ST, NATICK, MA 01760 USA SN 0736-6205 J9 BIOTECHNIQUES JI Biotechniques PD SEP PY 1999 VL 27 IS 3 BP 500 EP + PG 6 WC Biochemical Research Methods; Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 233VR UT WOS:000082448300017 PM 10489609 ER PT J AU Eberhard, WG AF Eberhard, WG TI Mortal mimicry in the fly, Plocoscelus sp (Diptera, Micropezidae) SO BIOTROPICA LA English DT Article DE Diptera; Micropezidae; mimicry; Plocoscelus C1 Univ Costa Rica, Smithsonian Trop Res Inst, San Jose, Costa Rica. Univ Costa Rica, Escuela Biol, San Jose, Costa Rica. RP Eberhard, WG (reprint author), Univ Costa Rica, Smithsonian Trop Res Inst, Ciudad Univ, San Jose, Costa Rica. NR 2 TC 1 Z9 1 U1 0 U2 1 PU ASSOC TROPICAL BIOLOGY INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044 USA SN 0006-3606 J9 BIOTROPICA JI Biotropica PD SEP PY 1999 VL 31 IS 3 BP 535 EP 535 DI 10.1111/j.1744-7429.1999.tb00399.x PG 1 WC Ecology SC Environmental Sciences & Ecology GA 248RA UT WOS:000083288100020 ER PT J AU DePriest, PT AF DePriest, PT TI Development of Mason E. Hale's list of epithets in the parmelioid genera (lichen-forming ascomycotina): A bibliographic review SO BRYOLOGIST LA English DT Review ID CONTINENTAL UNITED-STATES; PARMELIACEAE ASCOMYCOTINA; ALLIED FUNGI; GENUS XANTHOPARMELIA; CETRARIOID LICHENS; HALE ASCOMYCOTINA; 5TH CHECKLIST; WORLD LIST; CANADA; BULBOTHRICELLA AB Mason E. Hale's "List of Epithets in the Parmelioid Genera" provides a comprehensive view of his classification scheme for Parmelia s. lat. and its numerous segregate genera. Over Hale's three-decade career Parmelia Ach, went from a large, understudied genus, to a small genus with a constellation of more than 35 generic segregates, mostly erected by Hale and his close associates. A review of Hale's Extensive bibliography suggests that his classification scheme was fixed largely by the mid-1960s when he first treated Parmelia and proposed a new infrageneric classification for its neotropical species. Over the next 25 years, Hale and his colleagues divided the genus into relatively small, homologous groups of species in two stages. In a first stage in the mid-1970s, Hale developed new character systems that supported his recognition of many of the Parmelia infrageneric taxa as seven segregate genera. In a second stage in the mid-1980's, he and his colleagues refined these genera and named many new genera in response to newly available collections from Africa and Australia. Although Hale's classification of the parmelioid lichens remains controversial he introduced new ideas and new technologies to lichen taxonomy and systematics, especially the use of chemical characters and scanning electron microscope (SEM) examinations of the cortical structures. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, Washington, DC 20560 USA. RP DePriest, PT (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, NHB-166, Washington, DC 20560 USA. RI DePriest, Paula/K-6633-2015 NR 235 TC 18 Z9 19 U1 0 U2 1 PU AMER BRYOLOGICAL LICHENOLOGICAL SOCIETY INC PI FAIRFAX PA C/O JAMES D LAWREY, GEORGE MASON UNIV, DEPT BIOLOGY MSN 3E1, FAIRFAX, VA 22030 USA SN 0007-2745 J9 BRYOLOGIST JI Bryologist PD FAL PY 1999 VL 102 IS 3 BP 442 EP 461 DI 10.2307/3244233 PG 20 WC Plant Sciences SC Plant Sciences GA 235ZX UT WOS:000082574700013 ER PT J AU Hale, BW DePriest, PT AF Hale, BW DePriest, PT TI Mason E. Hale's list of epithets in the parmelioid genera SO BRYOLOGIST LA English DT Article AB Mason E. Hale, Jr. (1928-1990) distributed a preliminary "List of Epithets in the Parmelioid Genera" to many of his lichenological colleagues on 10 June 1989, The original list, an alphabetic arrangment of ephitets published in Parmelia s. lat. with their recommended placement in the over 30 segregrate parmelioid genera, was a valuable reference in locating species among the different schemes of classification in use in publications and in herbaria. Here we present an edited and updated version of that list. We have increased the number of entries of epithet combinations from 2,000 in the original list to over 4,000 Of these combinations, approximately 1,500 are accepted at the species rank. The epithets can be accessed through three formats: I) as a printed list of epithets that are arranged alphabetically, with their dispersions among the segregate gent ra and Parmelia s. str.; 2) as a printed list of accepted names tin the sense of Hale) with their basionyms and synonyms that are arranged by genus and species; and 3) as a searchable electronic database via http://www.nmnh.si.edu/departments/botany.html. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, Washington, DC 20560 USA. RP Hale, BW (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, NHB-166, Washington, DC 20560 USA. RI DePriest, Paula/K-6633-2015 NR 12 TC 30 Z9 37 U1 0 U2 0 PU AMER BRYOLOGICAL LICHENOLOGICAL SOCIETY INC PI FAIRFAX PA C/O JAMES D LAWREY, GEORGE MASON UNIV, DEPT BIOLOGY MSN 3E1, FAIRFAX, VA 22030 USA SN 0007-2745 J9 BRYOLOGIST JI Bryologist PD FAL PY 1999 VL 102 IS 3 BP 462 EP 544 DI 10.2307/3244234 PG 83 WC Plant Sciences SC Plant Sciences GA 235ZX UT WOS:000082574700014 ER PT J AU Staton, JL Rice, ME AF Staton, JL Rice, ME TI Genetic differentiation despite teleplanic larval dispersal: Allozyme variation in sipunculans of the Apionsoma misakianum species-complex SO BULLETIN OF MARINE SCIENCE LA English DT Article ID CRABS GENUS MENIPPE; GULF-OF-MEXICO; POPULATION-STRUCTURE; WESTERN ATLANTIC; CRASSOSTREA-VIRGINICA; BENTHIC INVERTEBRATES; LIMULUS-POLYPHEMUS; INTERTIDAL LIMPET; MITOCHONDRIAL-DNA; AMERICAN OYSTER AB We examined the genetic evidence for dispersal in the sipunculan Apionsoma misakianum (Ikeda 1904) by analysis of allozymes (using a total of nine polymorphic loci) in larval and adult samples. Genotypes of adults reared from late-stage larvae collected from the Florida Current were compared with genotypes of adults from three locations: eastern central Florida, the Florida Keys and the Bahamas. Genetic differences were found between individuals from the southern localities and the majority of specimens from the northern locality. The multilocus genotypes of the specimens reared from larvae of the Florida Current were characteristic of specimens from the Florida Keys and the Bahamas. Despite evidence for larval influx northward into the central-Florida area via the Florida Current, the southern genotypes were present in only a few adults collected (4.5%) at a northern site, with no indication of "hybrids" occurring between northern and southern genotype based on allozymes (i.e., heterozygotes). Furthermore, genetic separation of the northern and southern genotypes coincides with a faunal boundary noted for other species. C1 Smithsonian Marine Stn Ft Pierce, Ft Pierce, FL 34949 USA. RP Staton, JL (reprint author), Univ S Carolina, Belle W Baruch Inst Marine Biol & Coastal Res, Columbia, SC 29208 USA. EM jstaton@sc.edu NR 63 TC 11 Z9 11 U1 0 U2 3 PU ROSENSTIEL SCH MAR ATMOS SCI PI MIAMI PA 4600 RICKENBACKER CAUSEWAY, MIAMI, FL 33149 USA SN 0007-4977 EI 1553-6955 J9 B MAR SCI JI Bull. Mar. Sci. PD SEP PY 1999 VL 65 IS 2 BP 467 EP 480 PG 14 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA 233AL UT WOS:000082403300011 ER PT J AU Windsor, D Ness, J Gomez, LD Jolivet, PH AF Windsor, D Ness, J Gomez, LD Jolivet, PH TI Species of Aulacoscelis Duponchel and Chevrolat (Chrysomelidae) and Nomotus Gorham (Languriidae) feed on fronds of Central American cycads SO COLEOPTERISTS BULLETIN LA English DT Article ID RAIN-FOREST CYCAD; INSECT POLLINATION; ZAMIA-FURFURACEA; EUMAEUS-ATALA; SKINNERI; BEETLES AB Observations in Costa Rica and Panama verify a previously hypothesized feeding relationship between the enigmatic chrysomelid subfamily, Aulacoscelinae, and the "living fossil" Cycadophyta. Large populations of adult. Aulacoscelis sp. and A. costaricensis Bechyne were observed feeding on Zamia fairchildiana Gomez, a cycad native to lower Central America. Feeding was uncharacteristic of Chrysomelidae in that the mandibles were used to pierce the epidermis thereby releasing liquids which alone were ingested, Both species of Aulacoscelis Duponchal and Chevrolat also fed opportunistically on fronds damaged by adult Languriidae and larval Eumaeus goddarti (Hubner) (Lepidoptera, Lycaenidae) and on E. goddarti pupal exudates. Aulocoscelinae and Languriidae feeding was directed primarily at the first flush of cycad leaves produced at the beginning of the wet season-a pattern of adult beetle activity which collection records and observations indicate is widespread in Mexico and Central America. C1 Smithsonian Trop Res Inst, Balboa, Panama. RP Windsor, D (reprint author), Smithsonian Trop Res Inst, Apartado 2072, Balboa, Panama. NR 40 TC 10 Z9 14 U1 0 U2 1 PU COLEOPTERISTS SOC PI NATCHEZ PA P.O. BOX 767, NATCHEZ, MS 39121 USA SN 0010-065X J9 COLEOPTS BULL JI Coleopt. Bull. PD SEP PY 1999 VL 53 IS 3 BP 217 EP 231 PG 15 WC Entomology SC Entomology GA 241UF UT WOS:000082900400003 ER PT J AU Littler, MM Littler, DS AF Littler, MM Littler, DS TI Epithallus sloughing: a self-cleaning mechanism for coralline algae SO CORAL REEFS LA English DT Article C1 Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. Harbor Branch Oceanog Inst Inc, Div Marine Sci, Ft Pierce, FL 34946 USA. RP Littler, MM (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. NR 2 TC 10 Z9 11 U1 0 U2 5 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0722-4028 J9 CORAL REEFS JI Coral Reefs PD SEP PY 1999 VL 18 IS 3 BP 204 EP 204 DI 10.1007/s003380050182 PG 1 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 241WH UT WOS:000082906500002 ER PT J AU Woodley, NE AF Woodley, NE TI Lectotype designations in Xylomyidae and Stratiomyidae (Diptera) SO ENTOMOLOGICAL NEWS LA English DT Article AB Lectotypes are designated for Arthropeina fulva Lindner, 1949; Solva inamoena Walker, 1859; Xylophagus marginatus Meigen, 1820; and Xylophagus varius Meigen, 1820 in the Xylomyidae, and, Clitellaria aberrans Schiner, 1868; Oxycera liburna Walker, 1849; Cyclogaster peregrinus Hutton, 1901; Cyanauges ruficornis Schiner, 1868; Anacanthella splendens Macquart, 1855; and Exodontha villosa Lindner, 1969 in the Stratiomyidae. Dysbiota peregrina (Hutton), NEW COMBINATION and Spaniomyia liburna (Walker), NEW COMBINATION are proposed in the Stratiomyidae. C1 Smithsonian Inst, USDA ARS, PSI, Syst Entomol Lab, Washington, DC 20560 USA. RP Woodley, NE (reprint author), Smithsonian Inst, USDA ARS, PSI, Syst Entomol Lab, NHB 168, Washington, DC 20560 USA. RI Woodley, Norman/M-6160-2014 NR 12 TC 1 Z9 1 U1 0 U2 0 PU AMER ENTOMOL SOC PI PHILADELPHIA PA 1900 BENJ FRANKLIN PARKWAY, PHILADELPHIA, PA 19103-1195 USA SN 0013-872X J9 ENTOMOL NEWS JI Entomol. News PD SEP-OCT PY 1999 VL 110 IS 4 BP 201 EP 205 PG 5 WC Entomology SC Entomology GA 247VQ UT WOS:000083242000002 ER PT J AU Thompson, FC AF Thompson, FC TI A new oriental Sphegina species (Diptera : Syrphidae) SO ENTOMOLOGICAL NEWS LA English DT Article AB The only known Sphegina from the Philippines is described and named philippina (HT male Bishop Museum). C1 Smithsonian Inst, USDA ARS, Syst Entomol Lab, Washington, DC 20560 USA. RP Thompson, FC (reprint author), Smithsonian Inst, USDA ARS, Syst Entomol Lab, NHB-168, Washington, DC 20560 USA. NR 1 TC 1 Z9 1 U1 0 U2 2 PU AMER ENTOMOL SOC PI PHILADELPHIA PA 1900 BENJ FRANKLIN PARKWAY, PHILADELPHIA, PA 19103-1195 USA SN 0013-872X J9 ENTOMOL NEWS JI Entomol. News PD SEP-OCT PY 1999 VL 110 IS 4 BP 206 EP 208 PG 3 WC Entomology SC Entomology GA 247VQ UT WOS:000083242000003 ER PT J AU Wetterer, JK Miller, SE Wheeler, DE Olson, CA Polhemus, DA Pitts, M Ashton, IW Himler, AG Yospin, MM Helms, KR Harken, EL Gallaher, J Dunning, CE Nelson, M Litsinger, J Southern, A Burgess, TL AF Wetterer, JK Miller, SE Wheeler, DE Olson, CA Polhemus, DA Pitts, M Ashton, IW Himler, AG Yospin, MM Helms, KR Harken, EL Gallaher, J Dunning, CE Nelson, M Litsinger, J Southern, A Burgess, TL TI Ecological dominance by Paratrechina longicornis (Hymenoptera : Formicidae), an invasive tramp ant, in biosphere 2 SO FLORIDA ENTOMOLOGIST LA English DT Article DE ants; invasive species; microcosms; Paratrechina longicornis ID UNITED-STATES; BIODIVERSITY AB Tramp ante are invading disturbed ecosystems worldwide, exterminating untold numbers of native species. They have even invaded Biosphere 2, a 1.28-hectare closed greenhouse structure built in the Arizona desert as a microcosm for studying ecological interactions and global change. Invertebrate surveys within Biosphere 2 from 1990 to 1997 have revealed dramatic changes in faunal composition, including an almost complete replacement of the ant fauna by a single tramp ant species. In 1990-91, surveys in Biosphere 2 found no one ant species dominant. By 1993, populations of the crazy ant, Paratrechina longicornis (Latreille), a tramp species not found in 1990-91, had increased to extremely high levels. In 1996, virtually all ants (>99.9%) coming to bait were P. longicornis. We observed P. longicornis foragers feeding almost exclusively on the sugary excretions (honeydew) produced by vast numbers of Homoptera, primarily scale insects and mealybugs, found on many of the plants. High densities of ants were associated with high densities of homopterans. In 1997, soil and litter surveys found that the only invertebrates thriving in Biosphere 2, besides P. longicornis and homopterans, were either species with effective defenses against ants (well-armored isopods and millipedes) or tiny subterranean species that can escape ant predation (mites, thief ants, and springtails). A convergent pattern of biodiversity occurs in disturbed tropical and subtropical ecosystems dominated by tramp ants. C1 Florida Atlantic Univ, Honors COll, Jupiter, FL 33458 USA. Biosphere 2 Ctr, Oracle, AZ 85623 USA. Int Ctr Insect Physiol & Ecol, Nairobi, Kenya. Smithsonian Inst, Dept Entomol, Washington, DC 20560 USA. Arizona State Univ, Dept Zool, Tempe, AZ 85287 USA. Univ Calif Riverside, Dept Entomol, Riverside, CA 92521 USA. Inst Ecotech, Santa Fe, NM 87505 USA. RP Wetterer, JK (reprint author), Florida Atlantic Univ, Honors COll, 5353 Parkside Dr, Jupiter, FL 33458 USA. OI Miller, Scott/0000-0002-4138-1378 NR 19 TC 38 Z9 40 U1 5 U2 33 PU FLORIDA ENTOMOLOGICAL SOC PI LUTZ PA 16125 E LAKE BURRELL DR, LUTZ, FL 33548 USA SN 0015-4040 J9 FLA ENTOMOL JI Fla. Entomol. PD SEP PY 1999 VL 82 IS 3 BP 381 EP 388 DI 10.2307/3496865 PG 8 WC Entomology SC Entomology GA 306RT UT WOS:000086610600001 ER PT J AU Balling, RC Periconi, DA Cerveny, RS Baliunas, SL AF Balling, RC Periconi, DA Cerveny, RS Baliunas, SL TI Large asymmetrical temperature trends at Mount Wilson, California SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SURFACE-TEMPERATURE; CLIMATE-CHANGE; UNITED-STATES; MINIMUM TEMPERATURE; GREENHOUSE GASES; MAXIMUM; RANGE; MECHANISMS AB We compiled and analyzed a daily time series of temperatures and precipitation totals from Mount Wilson, California from 1918 to 1998. Our results show a large decline in maximum temperature, no change or an upward trend in minimum temperature, and a substantial decline in the diurnal temperature range (DTR). The interannual variations in monthly maximum temperature and DTR are significantly correlated with monthly precipitation levels, sea-surface temperatures (SSTs) off the coast of Southern California, and the Southern Oscillation Index(SOI). El Nino periods and/or months with high SST anomalies tend to be wet with lower maximum temperatures and DTR while La Nifia periods and/or months of lower SSTs are hotter and drier with higher DTR values. It is noteworthy that the SOI and SSTs have significant trends toward more El Nino-like conditions with higher SSTs off Southern California. C1 Arizona State Univ, Dept Geog, Tempe, AZ 85297 USA. Arizona State Univ, Off Climatol, Tempe, AZ 85297 USA. Harvard Smithsonian Ctr Astrophys, Cambridge & Mt Wilson Observ, Cambridge, MA 02138 USA. RP Balling, RC (reprint author), Arizona State Univ, Dept Geog, Tempe, AZ 85297 USA. NR 20 TC 1 Z9 1 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 SEP 1 PY 1999 VL 26 IS 17 BP 2753 EP 2756 DI 10.1029/1999GL006064 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 232VR UT WOS:000082391100030 ER PT J AU Shepard, MK Campbell, BA AF Shepard, MK Campbell, BA TI Radar scattering from a self-affine fractal surface: Near-nadir regime SO ICARUS LA English DT Article DE radar; surfaces/planets; venus/surface ID TOPOGRAPHY; PLAYA AB Planetary surfaces are better described by nonstationary fractal statistics than those more commonly assumed in current radar scattering models. Therefore, we have developed a radar scattering model applicable to self-affine fractal surfaces when observed near-nadir. The model predicts a family of angular scattering functions that smoothly transition between forms similar to the commonly utilized Hagfors, Gaussian, and exponential surface models. The model predicts that the near-nadir scattering behavior is determined by the wavelength-scaled roughness, i.e., the roughness that would be measured by a held worker using a ruler one wavelength in size, and the surface scaling behavior described by the fractal dimension or Hurst exponent. Additionally, this model predicts that the scattering behavior should scale with wavelength in a self-affine manner, i.e,, the scattering behavior at long wavelengths should look "smoother" than that at short wavelengths. The scattering behavior predicted by the model is consistent with that observed for Venus by the Magellan altimeter experiment. (C) 1999 Academic Press. C1 Bloomsburg Univ Penn, Dept Geog & Earth Sci, Bloomsburg, PA 17815 USA. Smithsonian Inst, Ctr Earth & Planetary Studies, Natl Air & Space Museum, Washington, DC 20005 USA. RP Shepard, MK (reprint author), Bloomsburg Univ Penn, Dept Geog & Earth Sci, 400 E 2nd St, Bloomsburg, PA 17815 USA. NR 35 TC 32 Z9 33 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD SEP PY 1999 VL 141 IS 1 BP 156 EP 171 DI 10.1006/icar.1999.6141 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 239EM UT WOS:000082755900011 ER PT J AU Tong, CE Blundell, R Papa, DC Smith, M Kawamura, J Gol'tsman, G Gershenzon, E Voronov, B AF Tong, CE Blundell, R Papa, DC Smith, M Kawamura, J Gol'tsman, G Gershenzon, E Voronov, B TI An all solid-state superconducting heterodyne receiver at terahertz frequencies SO IEEE MICROWAVE AND GUIDED WAVE LETTERS LA English DT Article DE solid-state terahertz LO; submillimeter-wave receivers; superconducting mixers ID SUBMILLIMETER AB A superconducting hot-electron bolometer mixer receiver operating from 1 to 1.26 THz has been developed. This heterodyne receiver employs two solid-state local oscillators each consisting of a Gunn oscillator followed by two stages of varactor frequency multiplication, The measured receiver noise temperature is 1350K at 1.035 THz and 2700K at 1.26 THz. This receiver demonstrates that tunable solid-state local oscillators, supplying only a few micro-watts of output power, can be used in terahertz receiver applications. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CALTECH, Pasadena, CA 91125 USA. Moscow State Pedag Univ, Moscow 119435, Russia. RP Tong, CE (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. OI Tong, Edward/0000-0002-7736-4203 NR 7 TC 7 Z9 7 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 1051-8207 J9 IEEE MICROW GUIDED W JI IEEE Microw. Guided Wave Lett. PD SEP PY 1999 VL 9 IS 9 BP 366 EP 368 DI 10.1109/75.790476 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA 239HH UT WOS:000082762400012 ER PT J AU Hacker, BC AF Hacker, BC TI Engineering the Revolution: Arms and enlightenment in France, 1763-1815. SO ISIS LA English DT Book Review C1 Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. RP Hacker, BC (reprint author), Smithsonian Inst, Natl Museum Amer Hist, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0021-1753 J9 ISIS JI Isis PD SEP PY 1999 VL 90 IS 3 BP 601 EP 601 DI 10.1086/384456 PG 1 WC History & Philosophy Of Science SC History & Philosophy of Science GA 247JJ UT WOS:000083217400046 ER PT J AU Ceruzzi, PE AF Ceruzzi, PE TI Electronic genie: The tangled history of silicon. SO ISIS LA English DT Book Review C1 Smithsonian Inst, Natl Air & Space Museum, Washington, DC 20560 USA. RP Ceruzzi, PE (reprint author), Smithsonian Inst, Natl Air & Space Museum, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0021-1753 J9 ISIS JI Isis PD SEP PY 1999 VL 90 IS 3 BP 633 EP 634 DI 10.1086/384492 PG 2 WC History & Philosophy Of Science SC History & Philosophy of Science GA 247JJ UT WOS:000083217400082 ER PT J AU Poulsen, LW Frohlich, B Charles, AV Brixen, K AF Poulsen, LW Frohlich, B Charles, AV Brixen, K TI Bone mineral density measurement of the Robert J. Terry anatomical collection shows sexual and ethnical differences in the femoral bones. SO JOURNAL OF BONE AND MINERAL RESEARCH LA English DT Meeting Abstract C1 Univ Aarhus, Dept Forens Med, Aarhus C, Denmark. Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. Odense Univ Hosp, Dept Endocrinol, DK-5000 Odense, Denmark. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC BONE & MINERAL RES PI DURHAM PA PO BOX 2759, DURHAM, NC 27715-2759 USA SN 0884-0431 J9 J BONE MINER RES JI J. Bone Miner. Res. PD SEP PY 1999 VL 14 SU 1 MA SU326 BP S513 EP S513 PG 1 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 232CA UT WOS:000082347101517 ER PT J AU Power, RA Jerome, CP Bailey, TS Power, MP Oftedal, OT Layne, DG Tardif, SD AF Power, RA Jerome, CP Bailey, TS Power, MP Oftedal, OT Layne, DG Tardif, SD TI Effects of pregnancy and lactation on parameters of maternal bone metabolism in the common marmoset monkey. SO JOURNAL OF BONE AND MINERAL RESEARCH LA English DT Meeting Abstract C1 Kent State Univ, Kent, OH 44242 USA. SkeleTech Inc, Bothell, WA USA. Smithsonian Inst, Washington, DC 20560 USA. NR 0 TC 2 Z9 2 U1 2 U2 2 PU AMER SOC BONE & MINERAL RES PI DURHAM PA PO BOX 2759, DURHAM, NC 27715-2759 USA SN 0884-0431 J9 J BONE MINER RES JI J. Bone Miner. Res. PD SEP PY 1999 VL 14 SU 1 MA F325 BP S274 EP S274 PG 1 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 232CA UT WOS:000082347100565 ER PT J AU Apponi, AJ McCarthy, MC Gottlieb, CA Thaddeus, P AF Apponi, AJ McCarthy, MC Gottlieb, CA Thaddeus, P TI The rotational spectrum of rhomboidal SiC3 SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID JET-COOLED SIC2; SPECTROSCOPY AB Rhomboidal SiC3, a planar ring with C-2v symmetry and a transannular C-C bond, was detected at centimeter wavelengths in a pulsed supersonic molecular beam with a Fourier transform microwave (FTM) spectrometer, and was subsequently observed in a low-pressure dc glow discharge with a free-space millimeter-wave absorption spectrometer. The rotational spectrum of SiC3 is characterized by large harmonic defects and large splitting of the K-type doublets. Lines in the centimeter-wave band were very strong, allowing the singly substituted isotopic species to be observed in natural abundance. Measurements of the normal and five isotopically substituted species with the FTM spectrometer provided conclusive evidence for the identification and yielded an experimental zero-point (r(0)) structure. Forty-six transitions between 11 and 286 GHz with K(a)less than or equal to 6 were measured in the main isotopic species. Three rotational and nine centrifugal distortion constants in Watson's A-reduced Hamiltonian reproduce the observed spectrum to within a few parts in 10(7) and allow the most intense transitions up to 300 GHz to be calculated with high accuracy. The spectroscopic constants confirm that SiC3 is a fairly rigid molecule: the inertial defect is comparable to those of well-known planar rings and the centrifugal distortion constants are comparable to molecules of similar size. The number of SiC3 molecules in our supersonic molecular beam in each gas pulse is at least 3x10(11), so large that electronic transitions may be readily detectable by laser spectroscopy. (C) 1999 American Institute of Physics. [S0021-9606(99)00330-X]. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. RP Apponi, AJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. OI McCarthy, Michael/0000-0001-9142-0008 NR 22 TC 63 Z9 67 U1 1 U2 6 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 SEP 1 PY 1999 VL 111 IS 9 BP 3911 EP 3918 DI 10.1063/1.479694 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 228BM UT WOS:000082116000018 ER PT J AU Pierce, RW Coats, DW AF Pierce, RW Coats, DW TI The feeding ecology of Actinophrys sol (Sarcodina : Heliozoa) in Chesapeake Bay SO JOURNAL OF EUKARYOTIC MICROBIOLOGY LA English DT Article DE ciliate; estuary; plankton; population dynamics ID CONTRACTION; CYCLE; LAKE AB The occurrence of Actinophrys sol, a planktonic heliozoan, in Chesapeake Bay was monitored over a four-year period (1988-1991). Actinophrys sol was widely-distributed throughout Chesapeake Bay and could exceed densities of 5,000 cells liter(-1). It was most abundant during the warmer months. Feeding experiments were conducted with field populations of heliozoa using 1-mu m fluorescent microspheres to label ciliate prey. Two ciliates, a small Strobilidium sp. (30 mu m in diameter) and a Pleuronema sp. (45 mu m length), were the primary ciliate-prey items in the water column when the experiments were conducted, although a wide range of ciliate taxa was ingested. Two other ciliates not present in situ, a Cyclidium sp. (20 mu m length) and a Uronema sp. (40 mu m length), were also labeled and added at various concentrations to field populations of plankton containing A. sol. Heliozoan ingestion rates on in situ prey at concentrations of 30 Strobilidium and one Pleuronema ml(-1) were 0.2 to 0.3 prey heliozoan(-1) hour(-1). Ingestion rates increased to a maximum of 1.2 prey heliozoan(-1) hour(-1) with additions of 100 Uronema ml(-1). A mean clearance rate of 0.15 ml heliozoan(-1) day(-1) did not change with increasing prey abundance. The abundance and distribution of A. sal suggests that these sarcodines may exert strong grazing pressure on the planktonic ciliate populations of Chesapeake Bay at certain times of the year, and may be important in shaping the ciliate community composition and distribution. C1 Smithsonian Environm Res Ctr, Edgewater, MD 21401 USA. RP Pierce, RW (reprint author), POB 132, N Attleboro, MA 02761 USA. NR 27 TC 4 Z9 5 U1 0 U2 2 PU SOC PROTOZOOLOGISTS PI LAWRENCE PA 810 E 10TH ST, LAWRENCE, KS 66044 USA SN 1066-5234 J9 J EUKARYOT MICROBIOL JI J. Eukaryot. Microbiol. PD SEP-OCT PY 1999 VL 46 IS 5 BP 451 EP 457 DI 10.1111/j.1550-7408.1999.tb06060.x PG 7 WC Microbiology SC Microbiology GA 242TZ UT WOS:000082958900001 ER PT J AU Baccino, E Ubelaker, DH Hayek, LAC Zerilli, A AF Baccino, E Ubelaker, DH Hayek, LAC Zerilli, A TI Evaluation of seven methods of estimating age at death from mature human skeletal remains SO JOURNAL OF FORENSIC SCIENCES LA English DT Article DE forensic science; skeletal age estimation; comparison ID STERNAL RIB; WHITE MALES; PHASE-ANALYSIS; FEMALES AB Different approaches to the estimation of age at death in mature human skeletal remains were evaluated utilizing samples from 19 recent French autopsy individuals of known age at death. Methods of estimating age at death from single-rooted teeth, the sternal ends of the fourth ribs, the symphyseal face of the pubis and femoral cortical remodeling were evaluated by two independent observers (three observers for the teeth). Comparison included ages estimated from three more comprehensive approaches utilizing data from the application of two or more of the individual methods. The results indicate that the comprehensive approaches are superior to the individual ones and the success of the latter reflects not only the morphological expression of the aging process, but also the technique complexity and the experience of the investigator Of the individual techniques, the "Lamendin" dental technique was most effective for individuals of ages greater than 25 years. C1 CHU Montpellier, Montpellier, France. Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. CHU Brest, F-29285 Brest, France. RP Baccino, E (reprint author), Hop Lapeyronie, 371 Av Doyen Gaston Giraud, F-34295 Montpellier 5, France. NR 15 TC 71 Z9 73 U1 5 U2 20 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 USA SN 0022-1198 J9 J FORENSIC SCI JI J. Forensic Sci. PD SEP PY 1999 VL 44 IS 5 BP 931 EP 936 PG 6 WC Medicine, Legal SC Legal Medicine GA 293AZ UT WOS:000085830500009 PM 10486944 ER PT J AU Li, X AF Li, X TI Proton temperature anisotropy in the fast solar wind: A 16-moment bi-Maxwellian model SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID TRANSPORT-EQUATIONS; VELOCITY DISTRIBUTIONS; POLAR WIND; HYDRODYNAMIC MODELS; ASTROPHYSICAL WINDS; IONOSPHERIC PLASMA; GENERALIZED-MODEL; GRAD EXTENSION; SPACE PLASMAS; CORONAL HOLE AB A 16-moment bi-Maxwellian model to describe the proton temperature anisotropy and heat flux density in the fast solar wind is presented. Although the proton total heat flux density in this model is found to be significantly smaller than the classical Coulomb collision-dominated Spitzer-Harm heat Aux density, it still plays a significant role in shaping the proton temperature anisotropy. The proton total heat flux density matches the value observed between 0.3 and 1 AU when the proton temperature is also close to the observed value. A large temperature anisotropy in the inner corona, with a proton perpendicular temperature higher than the parallel temperature, as indicated by recent ultraviolet observations, leads to a higher perpendicular heat flux. Since the perpendicular heat flux conduces energy from the perpendicular to the parallel degree of freedom, an unrealistically high parallel temperature develops in interplanetary space if no cooling mechanism for protons in the direction parallel to the magnetic field is introduced. This study suggests that with a bi-Maxwellian-base 16-moment description of the solar wind protons the high proton perpendicular temperature implied by the Ultraviolet Coronagraph Spectrometer on board Solar and Heliospheric Observatory in the inner corona and by in situ measurements from Helios place strong constraints on the proton heating mechanism: not only must the protons be heated in the direction perpendicular to the magnetic field, but they must also be cooled in the parallel direction. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM xli@cfa.harvard.edu NR 52 TC 38 Z9 38 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9380 EI 2169-9402 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD SEP 1 PY 1999 VL 104 IS A9 BP 19773 EP 19785 DI 10.1029/1999JA900255 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 232FK UT WOS:000082360100003 ER PT J AU Hamilton, MB Fleischer, RC AF Hamilton, MB Fleischer, RC TI Cloned microsatellite repeats differ between 4-base restriction endonucleases SO JOURNAL OF HEREDITY LA English DT Article ID LINKAGE MAP; GENOME; LOCI AB Simple sequence repeat (SSR) loci are an important marker type for population genetic studies despite the limitation that development of novel loci requires construction and screening of genomic DNA libraries. The common practice of size fractioning genomic DNA before cloning could lead to differential representation of SSR loci within genomic libraries. In addition, linkage mapping studies have shown that small numbers of SSR markers are not randomly distributed within the genomes from which they are isolated. From attempts to clone five SSR repeat sequences in two wild plant species we show that the numbers and repeat type of potential SSR markers depend on the restriction endonuclease used to sample the genome when constructing DNA libraries. This observation is consistent with unequal sampling of the genome by different restriction enzymes. However, as a group the five SSR repeal sequences are not associated with a given restriction enzyme, suggesting they are not clumped within the genome. Use of multiple restriction enzymes to construct DNA libraries may help ensure that cloned SSR loci are drawn from diverse locations in the genome, helping to meet the assumption of randomly located marker loci required for population genetic inferences. C1 Smithsonian Inst, Mol Genet Lab, Washington, DC 20560 USA. RP Hamilton, MB (reprint author), Smithsonian Inst, Mol Genet Lab, Natl Zool Pk, Washington, DC 20560 USA. NR 9 TC 9 Z9 10 U1 0 U2 0 PU OXFORD UNIV PRESS INC PI CARY PA JOURNALS DEPT, 2001 EVANS RD, CARY, NC 27513 USA SN 0022-1503 J9 J HERED JI J. Hered. PD SEP-OCT PY 1999 VL 90 IS 5 BP 561 EP 563 DI 10.1093/jhered/90.5.561 PG 3 WC Evolutionary Biology; Genetics & Heredity SC Evolutionary Biology; Genetics & Heredity GA 248AX UT WOS:000083254100011 PM 10544499 ER PT J AU Linnartz, H Motylewski, T Vaizert, O Maier, JP Apponi, AJ McCarthy, MC Gottlieb, CA Thaddeus, P AF Linnartz, H Motylewski, T Vaizert, O Maier, JP Apponi, AJ McCarthy, MC Gottlieb, CA Thaddeus, P TI Electronic ground and excited state spectroscopy of C6H and C6D SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article ID CARBON CHAINS; GAS-PHASE; RADICALS; IRC+10216; SPECTRA; PARAMETERS; MOLECULES; (2)PI; C10H; C8H AB Rotational transitions in the X(2)Pi ground state of C6H and C6D have been measured by Fourier transform microwave and millimeter-wave absorption spectroscopy. More than 150 rotational lines in the ground (2)Pi(3/2) and (2)Pi(1/2) ladders have been observed, allowing an accurate determination of the rotational, fine structure, lambda-doubling, and hyperfine coupling constants using a standard effective Hamiltonian for a molecule in an isolated Zn electronic state. The molecular ground state constants are used to characterize the rotationally resolved origin band of the (2)Pi <-- X(2)Pi: electronic transition observed by cavity ring-down laser absorption spectroscopy in a pulsed supersonic slit-jet discharge source. From these data, spectroscopic constants for the excited electronic state are determined. (C) 1999 Academic Press. C1 Univ Basel, Inst Phys Chem, CH-4056 Basel, Switzerland. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. RP Linnartz, H (reprint author), Univ Basel, Inst Phys Chem, Klingelbergstr 80, CH-4056 Basel, Switzerland. OI McCarthy, Michael/0000-0001-9142-0008 NR 35 TC 47 Z9 47 U1 1 U2 13 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD SEP PY 1999 VL 197 IS 1 BP 1 EP 11 DI 10.1006/jmsp.1999.7885 PG 11 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 230KF UT WOS:000082249800001 ER PT J AU Boardman, RS AF Boardman, RS TI Indications of polypides in feeding zooids and polymorphs in Lower Paleozoic trepostomata (Bryozoa) SO JOURNAL OF PALEONTOLOGY LA English DT Article AB Delicate symmetrical structures in living chambers of autozooecia of some lower Paleozoic species of the order Trepostomata have been interpreted as indications of polypides with little further elaboration. Applications of the anatomy, mode of skeletal growth, and functional requirements basic to living species permit recognition of a few organs of these partially preserved polypides, their functions, and their relationships to enclosing skeletons. Only one basic polypide anatomy is indicated in lower Paleozoic trepostome species, in contrast to the wide diversity of polypide anatomy and their lack of correlation with skeletal characteristics in living stenolaemates. In general, the longer the evolutionary history, the greater the diversity of skeletal morphology in stenolaemates. Apparently, polypide diversity and lack of correlation with skeletal morphology also have increased over time. The complex skeletal septa in autozooecial apertures of the lower Paleozoic trepostome Hallopora have been interpreted as reflecting an organ of full-sized feeding polypides. Applications of the basic biological concepts of living species suggest that the septa provided reduced skeletal apertures to fit smaller polypides of polymorphs that secondarily occupied the living chambers of full-sized degenerated feeding polypides. C1 Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. RP Boardman, RS (reprint author), 3612 E Forest Lake Dr, Sarasota, FL 34232 USA. NR 41 TC 4 Z9 4 U1 1 U2 1 PU PALEONTOLOGICAL SOC INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044 USA SN 0022-3360 J9 J PALEONTOL JI J. Paleontol. PD SEP PY 1999 VL 73 IS 5 BP 803 EP 815 PG 13 WC Paleontology SC Paleontology GA 266WY UT WOS:000084324300005 ER PT J AU Jucks, KW Rodrigues, R Le Doucen, R Claveau, C Traub, WA Hartmann, JM AF Jucks, KW Rodrigues, R Le Doucen, R Claveau, C Traub, WA Hartmann, JM TI Model, software, and database for computation of line-mixing effects in infrared Q branches of atmospheric CO2: II Minor and asymmetric isotopomers SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article ID BANDS; PRESSURE AB The influence of line-mixing on the shape of infrared Q branches of minor isotopomers of CO2 is studied for the first time. Laboratory spectra of isotopically enriched CO2-N-2 mixtures have been measured in the 15 mu m region at the temperatures of 200 and 300 K for total pressures between 1 and 10 atm. Comparisons with measurements for the nu(2) and (nu(1)-nu(2))(1) Q branches of the six isotopomers O-(16,O-17,O- or 18)-C-12-O-(16,O-17,O- or 18) demonstrate the quality of the theoretical approach presented in the preceding paper (Part I). The model is used to generate a set of numerical data (available by ftp) for the prediction of absorption by (OCO)-O-16-C-12-O-18, (OCO)-O-16-C-12-O-17, (OCO)-O-16-C-13-O-18 (OCO)-O-16-C-13-O-17, and (OCO)-O-17-C-12-O-18 infrared Q branches under atmospheric conditions; this database completes that proposed in the preceding paper and now includes 271 bands considering the eight most abundant CO2 isotopomers. Its quality is tested by comparisons with atmospheric limb emission measured by a balloon-borne high resolution Fourier transform instrument. The nu(2) Q branches of (OCO)-O-16-C-12-O-16, (OCO)-O-16-C-13-O-16, (OCO)-O-16-C-12-O-17, and (OCO)-O-16-C-12-O-18 recorded above Alaska have been used. This shows that line mixing has significant effects, even for minor isotopomers, and is correctly accounted for by the model and data proposed, (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ Paris Sud, Lab Phys Mol & Applicat, CNRS, UPR 136, F-91405 Orsay, France. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Univ Rennes 1, Lab Phys Atomes Lasers Mol & Surfaces, F-35042 Rennes, France. Univ Paris 06, F-91405 Orsay, France. RP Hartmann, JM (reprint author), Univ Paris Sud, Lab Phys Mol & Applicat, CNRS, UPR 136, F-91405 Orsay, France. NR 14 TC 18 Z9 19 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-4073 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD SEP PY 1999 VL 63 IS 1 BP 31 EP 48 DI 10.1016/S0022-4073(98)00133-2 PG 18 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 205BW UT WOS:000080802300003 ER PT J AU Arnoldi, MJ AF Arnoldi, MJ TI Mande potters and leather-workers: art and heritage in West Africa. SO JOURNAL OF THE ROYAL ANTHROPOLOGICAL INSTITUTE LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Arnoldi, MJ (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ROYAL ANTHROPOLOGICAL INST PI LONDON PA 50 FITZROY STREET, LONDON, ENGLAND W1P 5HS SN 1359-0987 J9 J ROY ANTHROPOL INST JI J. R. Anthropol. Inst. PD SEP PY 1999 VL 5 IS 3 BP 476 EP 477 DI 10.2307/2661296 PG 2 WC Anthropology SC Anthropology GA 239ZB UT WOS:000082799800026 ER PT J AU Prussin, L AF Prussin, L TI Non-Western sacred sites: African models SO JOURNAL OF THE SOCIETY OF ARCHITECTURAL HISTORIANS LA English DT Article C1 Smithsonian Inst, Natl Museum African Art, Washington, DC 20560 USA. RP Prussin, L (reprint author), Smithsonian Inst, Natl Museum African Art, Washington, DC 20560 USA. NR 11 TC 2 Z9 2 U1 1 U2 1 PU SOC ARCHITECTURAL HISTORIANS PI CHICAGO PA 1365 NORTH ASTOR ST, CHICAGO, IL 60610-2144 USA SN 0037-9808 J9 J SOC ARCHIT HIST JI J. Soc. Archit. Hist. PD SEP PY 1999 VL 58 IS 3 SI SI BP 424 EP 433 DI 10.2307/991536 PG 10 WC Architecture SC Architecture GA 274LU UT WOS:000084768000018 ER PT J AU Kalfatovic, MR AF Kalfatovic, MR TI The fake: Forgery and its place in art. SO LIBRARY JOURNAL LA English DT Book Review C1 Smithsonian Inst Libs, Washington, DC 20560 USA. RP Kalfatovic, MR (reprint author), Smithsonian Inst Libs, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU BOWKER MAGAZINE GROUP CAHNERS MAGAZINE DIVISION PI NEW YORK PA 249 W 17TH ST, NEW YORK, NY 10011 USA SN 0363-0277 J9 LIBR J JI Libr. J. PD SEP 1 PY 1999 VL 124 IS 14 BP 190 EP 190 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 232DB UT WOS:000082349500065 ER PT J AU Ivanova, NV DePriest, PT Bobrova, VK Troitsky, AV AF Ivanova, NV DePriest, PT Bobrova, VK Troitsky, AV TI Phylogenetic analysis of the lichen family Umbilicariaceae based on nuclear ITS1 and ITS2 rDNA sequences SO LICHENOLOGIST LA English DT Article; Proceedings Paper CT Workshop on Progress in Molecular Studies of Lichens CY AUG 11-14, 1998 CL GRAZ, AUSTRIA SP Perkin Elmer, Steir Landesreger, Osterreich Adademie Wissensch, Osterreich Forschungsgemein, BMFWV, OGGGT ID 18S RIBOSOMAL-RNA; SSU RDNA; FUNGI; INSERTIONS; POSITION; DNA AB The lichen family Umbilicariaceae is accepted by most lichenologists as consisting of two genera, Lasallia and Umbilicaria. The monophyly of these two genera was examined by phylogenetic analyses of nucleotide sequences of ITS1 and ITS2 rDNA. Sequences of these regions from three Lasallia and 17 Umbilicaria species were aligned to those of seven representatives of the outgroup taxa including Eurotiales, Onygenales and Caliciales (Mycocaliciaceae) and subjected to maximum parsimony, maximum likelihood and neighbour-joining analyses. The resulting phylogenetic hypotheses supported the monophyly of the representative species of Lasallia. However, the species of Umbilicaria did not form a monophyletic sister-group to Lasallia due to the basal placement of other Umbilicaria species in some analyses. Based on these analyses, if Lasallia is recognized as a separate genus then Umbilicaria appears to be paraphyletic. Although further taxon sampling is required to resolve the monophyly of Umbilicaria, for the present we recommend retaining the current treatment of Lasallia as separate from Umbilicaria. (C) 1999 The British Lichen Society. C1 RAS, VA Engelhardt Mol Biol Inst, Grp Automated DNA Sequencing, Moscow 117984, Russia. Smithsonian Inst, Museum Natl Hist Nat, Dept Bot, Washington, DC 20560 USA. Moscow MV Lomonosov State Univ, Belozersky Inst Physicochem Biol, Plant Genosystemat Lab, Dept Evolutionary Biochem, Moscow 117899, Russia. RP Ivanova, NV (reprint author), RAS, VA Engelhardt Mol Biol Inst, Grp Automated DNA Sequencing, 32 Vavilova St, Moscow 117984, Russia. EM seq373@genome.eimb.relarn.ru RI DePriest, Paula/K-6633-2015 NR 34 TC 14 Z9 16 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI CAMBRIDGE PA EDINBURGH BLDG, SHAFTESBURY RD, CB2 8RU CAMBRIDGE, ENGLAND SN 0024-2829 J9 LICHENOLOGIST JI Lichenologist PD SEP PY 1999 VL 31 BP 477 EP 489 PN 5 PG 13 WC Plant Sciences; Mycology SC Plant Sciences; Mycology GA 253TT UT WOS:000083572400008 ER PT J AU McCoy, TJ Dickinson, TL Lofgren, GE AF McCoy, TJ Dickinson, TL Lofgren, GE TI Partial melting of the Indarch (EH4) meteorite: A textural, chemical, and phase relations view of melting and melt migration SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID UNEQUILIBRATED ENSTATITE CHONDRITES; AUBRITE PARENT BODY; OLDHAMITE; ORIGIN; ACHONDRITES; EVOLUTION; METAL AB To test whether aubrites can be formed by melting of enstatite chondrites and to understand igneous processes at very low O fugacities, we have conducted partial melting experiments on the Indarch (EH4) chondrite at 1000-1500 C. Silicate melting begins at 1000 C, and Indarch is completely melted by 1500 C. The metal-sulfide component melts completely at 1000 degrees C. Substantial melt migration occurs at 1300-1400 C, and metal migrates out of the silicate charge at 1450 C and similar to 50% silicate partial melting. As a group, our experiments contain three immiscible metallic melts (Si-, P-, and C-rich), two immiscible sulfide melts (Fe- and FeMgMnCa-rich), and silicate melt. Our partial melting experiments on the Indarch (EH4) enstatite chondrite suggest that igneousprocesses at low fO(2) exhibit several unique features. The complete melting of sulfides at 1000 C suggests that aubritic sulfides are not relics. Aubritic oldhamite may have crystallized from Ca and S complexed in the silicate melt. Significant metal-sulfide melt migration might occur at relatively low degrees of silicate partial melting. Substantial elemental exchange occurredbetween different melts (e.g., S between sulfide and silicate, Si between silicate and metal), a feature not observed during experiments at higher fO(2). This exchange may help explain the formation of aubrites from known enstatite chondrites. C1 Smithsonian Inst, Natl Air & Space Museum, Dept Mineral Sci, Washington, DC 20560 USA. Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP McCoy, TJ (reprint author), Smithsonian Inst, Natl Air & Space Museum, Dept Mineral Sci, Washington, DC 20560 USA. NR 39 TC 105 Z9 105 U1 0 U2 9 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD SEP PY 1999 VL 34 IS 5 BP 735 EP 746 PG 12 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 240XG UT WOS:000082851900007 ER PT J AU Ehlmann, AJ McCoy, TJ AF Ehlmann, AJ McCoy, TJ TI Oscar E. Monnig (1902-1999) - Memorial SO METEORITICS & PLANETARY SCIENCE LA English DT Biographical-Item C1 Texas Christian Univ, Dept Geol, Ft Worth, TX 76129 USA. Smithsonian Inst, Museum Natl Hist Nat, Dept Mineral Sci, Washington, DC 20560 USA. RP Ehlmann, AJ (reprint author), Texas Christian Univ, Dept Geol, Ft Worth, TX 76129 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD SEP PY 1999 VL 34 IS 5 BP 817 EP 817 PG 1 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 240XG UT WOS:000082851900017 ER PT J AU Lovette, IJ Bermingham, E Rohwer, S Wood, C AF Lovette, IJ Bermingham, E Rohwer, S Wood, C TI Mitochondrial restriction fragment length polymorphism (RFLP) and sequence variation among closely related avian species and the genetic characterization of hybrid Dendroica warblers SO MOLECULAR ECOLOGY LA English DT Article DE Dendroica; DNA sequence; evolutionary rates; hybrid; phylogenetic analysis; phylogeography; restriction fragment length polymorphism ID CYTOCHROME-B; EVOLUTIONARY RELATIONSHIPS; TOWNSENDS WARBLERS; DNA EVOLUTION; SPECIATION; COMPLEX; RATES; PLEISTOCENE; POPULATIONS; PHYLOGENIES AB To address several interconnected goals, we used mitochondrial DNA (mtDNA) sequences to explore evolutionary relationships among four potentially hybridizing taxa in a North American avian superspecies (Dendroica occidentalis, D. townsendi, D. virens, and D. nigrescens). We first compared the results of a previous restriction fragment length polymorphism (RFLP)-based study with 1453 nucleotides from the mitochondrial cytochrome oxidase subunit I(COI), ATP-synthase 6 (ATPase 6), and ATP-synthase 8 (ATPase 8) genes. Separate phylogenetic analyses of the RFLP and sequence data provided identical and well-supported hierarchical species-level reconstructions that grouped occidentalis and townsendi as sister taxa. We then explored several general features of mitochondrial evolution via a comparison of the RFLP and sequence data sets. Qualitative rate differences that seemed evident in highly autocorrelated comparisons of RFLP vs, sequence pairwise distances were not supported when autocorrelation was removed. We also noted a high variance in corresponding RFLP and sequence distances after the removal of autocorrelation effects. This variance suggests that caution should be used when combining RFLP and sequence-based data in studies that require the large-scale synthesis of divergence estimates drawn from sources employing different molecular techniques. Finally, we used our parallel RFLP and sequence data to design and validate a rapid and inexpensive polymerase chain reaction-RFLP (PCR-RFLP) protocol for determining species-specific mitochondrial haplotypes. This PCR-RFLP technique will be applied in ongoing studies of the occidentalis/townsendi hybrid zone, where the historic and geographical complexity of the interbreeding populations necessitates the genotyping of thousands of individual warblers. C1 Smithsonian Trop Res Inst, Balboa, Panama. Univ Penn, Dept Biol, Philadelphia, PA 19104 USA. Univ Washington, Burke Museum, Seattle, WA 98195 USA. Univ Washington, Dept Zool, Seattle, WA 98195 USA. RP Lovette, IJ (reprint author), Smithsonian Trop Res Inst, Apartado 2072, Balboa, Panama. RI Lovette, Irby/P-3477-2014 NR 37 TC 25 Z9 27 U1 0 U2 6 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0962-1083 J9 MOL ECOL JI Mol. Ecol. PD SEP PY 1999 VL 8 IS 9 BP 1431 EP 1441 DI 10.1046/j.1365-294x.1999.00706.x PG 11 WC Biochemistry & Molecular Biology; Ecology; Evolutionary Biology SC Biochemistry & Molecular Biology; Environmental Sciences & Ecology; Evolutionary Biology GA 252JL UT WOS:000083498300006 PM 10564448 ER PT J AU Winker, K Glenn, TC Graves, GR AF Winker, K Glenn, TC Graves, GR TI Dinucleotide microsatellite loci in a migratory wood warbler (Parulidae : Limnothlypis swainsonii) and amplification among other songbirds SO MOLECULAR ECOLOGY LA English DT Article DE aves; nearctic-neotropic migrants; Passeriformes; Swainson's warbler ID DNA; PROTOCOL C1 Natl Museum Nat Hist, Lab Mol Systemat, Smithsonian Inst, MSC MRC 534, Washington, DC 20560 USA. RP Winker, K (reprint author), Univ Alaska Museum, 907 Yukon Dr, Fairbanks, AK 99775 USA. RI Glenn, Travis/A-2390-2008; Winker, Kevin/M-2042-2014 OI Winker, Kevin/0000-0002-8985-8104 NR 8 TC 27 Z9 27 U1 0 U2 1 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0962-1083 J9 MOL ECOL JI Mol. Ecol. PD SEP PY 1999 VL 8 IS 9 BP 1553 EP 1556 DI 10.1046/j.1365-294X.1999.07113.x PG 4 WC Biochemistry & Molecular Biology; Ecology; Evolutionary Biology SC Biochemistry & Molecular Biology; Environmental Sciences & Ecology; Evolutionary Biology GA 252JL UT WOS:000083498300023 ER PT J AU Aymard, G Dorr, LJ Cuello, N AF Aymard, G Dorr, LJ Cuello, N TI Rudgea tayloriae (Rubiaceae), an unusual new species from the eastern slopes of the Venezuelan Andes SO NOVON LA English DT Article AB Rudgea tayloriae (Rubiaceae), a new species from the eastern slopes of the Venezuelan Andes, is described and illustrated, and its relationships are discussed. C1 Herbario Univ PORT, Programa Recursos Nat Renovables, UNELLEZ Guanare, Edo Portuguesa 3323, Venezuela. Smithsonian Inst, Museum Natl Hist Nat, Dept Bot, Washington, DC 20560 USA. RP Aymard, G (reprint author), Herbario Univ PORT, Programa Recursos Nat Renovables, UNELLEZ Guanare, Mesa de Cavacas, Edo Portuguesa 3323, Venezuela. NR 9 TC 2 Z9 2 U1 0 U2 0 PU MISSOURI BOTANICAL GARDEN PI ST LOUIS PA 2345 TOWER GROVE AVENUE, ST LOUIS, MO 63110 USA SN 1055-3177 J9 NOVON JI Novon PD FAL PY 1999 VL 9 IS 3 BP 315 EP 317 PG 3 WC Plant Sciences SC Plant Sciences GA 238MK UT WOS:000082713900006 ER PT J AU Wagner, WL Shannon, RK AF Wagner, WL Shannon, RK TI Nomenclator of Hawaiian Sicyos (Cucurbitaceae) SO NOVON LA English DT Article AB In 1987 Harold St. John published 69 names in Hawaiian Cucurbitaceae in four short papers. The nomenclature is analyzed, and the complete nomenclature of the Hawaiian species of Sicyos is presented, including 105 names. Names described by St. John in Sicyos and the segregate genus Cladocarpa were incorporated by Telford in his 1990 treatment, but those names described in the segregate genera Sarx (1 name) and Sicyocarya (14 names) were not treated and are here placed in Telford's classification. Five of the taxa described by St. John in 1987 were recognized in Telford's taxonomy (Cladocarpa herbstii [= Sicyos herbstii], Sicyos hillebrandii var. anunu [= S. anunu], S. erostratus, S. waimanaloensis, and Sicyocarya lanceoloidea [as sp. A = Sicyos lanceoloideus]). Two of these were transferred to Sicyos by Telford, and one of them is here transferred to Sicyos [Sicyocarya lanceoloidea]. All of the other taxa described by St. John are placed in the synonymy of other species. Five of the names were not validly published (Cladocarpa kawelaensis, Sicyocarya cruralis, Sicyocarya hawaiiensis, Sicyos erostratus var. kealiaensis, and Sicyos microcarpus var. kealiaensis). C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, Washington, DC 20560 USA. RP Wagner, WL (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, MRC 166, Washington, DC 20560 USA. NR 15 TC 1 Z9 1 U1 0 U2 0 PU MISSOURI BOTANICAL GARDEN PI ST LOUIS PA 2345 TOWER GROVE AVENUE, ST LOUIS, MO 63110 USA SN 1055-3177 J9 NOVON JI Novon PD FAL PY 1999 VL 9 IS 3 BP 441 EP 447 DI 10.2307/3391749 PG 7 WC Plant Sciences SC Plant Sciences GA 238MK UT WOS:000082713900028 ER PT J AU Wagner, WL Weller, SG AF Wagner, WL Weller, SG TI Rediscovery and assessment of Stenogyne sherffii Degener (Lamiaceae) SO NOVON LA English DT Article AB Stenogyne sherffii O.. Degener from the Ko'olau Mountains, O'ahu, Hawaiian Islands, was treated as synonymous with the more common species from the Wai'anae Mountains, S. kaalae Wawra, in the most recent revision of the genus by Weller and Sakai in 1990. A single population of about five plants of this entity was rediscovered in 1994. A plant was propagated from a stem cutting in the greenhouse at the University of California, Irvine. Comparison to plants of S. kaalae grown in the same greenhouse and herbarium material shows that the rare Ko'olau plants are distinct in several characters, especially subentire vs. serrate leaves. We here recognize this taxon as a subspecies of S. kaalae because of the clear species synapomorphy of very dark maroon corolla color and the geographical separation of the two taxa. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, Washington, DC 20560 USA. Univ Calif Irvine, Dept Ecol & Evolutionary Biol, Irvine, CA 92717 USA. RP Wagner, WL (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, MRC-166, Washington, DC 20560 USA. NR 3 TC 4 Z9 4 U1 0 U2 2 PU MISSOURI BOTANICAL GARDEN PI ST LOUIS PA 2345 TOWER GROVE AVENUE, ST LOUIS, MO 63110 USA SN 1055-3177 J9 NOVON JI Novon PD FAL PY 1999 VL 9 IS 3 BP 448 EP 449 DI 10.2307/3391750 PG 2 WC Plant Sciences SC Plant Sciences GA 238MK UT WOS:000082713900029 ER PT J AU Wasshausen, DC AF Wasshausen, DC TI New species of Justicia (Acanthaceae) from Cerro La Chapa, El Amparo, Venezuela SO NOVON LA English DT Article AB Current research in the cloud forest of Cerro La Chapa, El Amparo, by Winfried Meier has resulted in the recognition of a new species of Justicia. This new species, Justicia chapana previously misidentified as J. galapagana Lindau, is described, illustrated, and compared to the latter, its closest relative, from the Galapagos Islands. C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, Washington, DC 20560 USA. RP Wasshausen, DC (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Bot, Washington, DC 20560 USA. NR 2 TC 0 Z9 0 U1 1 U2 1 PU MISSOURI BOTANICAL GARDEN PI ST LOUIS PA 2345 TOWER GROVE AVENUE, ST LOUIS, MO 63110 USA SN 1055-3177 J9 NOVON JI Novon PD FAL PY 1999 VL 9 IS 3 BP 450 EP 452 DI 10.2307/3391751 PG 3 WC Plant Sciences SC Plant Sciences GA 238MK UT WOS:000082713900030 ER PT J AU Newman, MEJ Eble, GJ AF Newman, MEJ Eble, GJ TI Decline in extinction rates and scale invariance in the fossil record SO PALEOBIOLOGY LA English DT Article ID BACKGROUND EXTINCTION; MASS EXTINCTIONS; EVOLUTION; NOISE; ORIGINATION; STATISTICS; DIVERSITY; PATTERNS; MODEL; TAXA AB We show that the decline in the extinction rate during the Phanerozoic can be accurately described by a logarithmic fit to the cumulative total extinction. This implies that extinction intensity is hiring off approximately as the reciprocal of time. We demonstrate that this observation alone is sufficient to explain the existence of the proposed power-law forms in the distribution of the sizes of extinction events and in the power spectrum of Phanerozoic extinction, results that previously have been explained by appearing to self-organized critical theories of evolutionary dynamics. C1 Santa Fe Inst, Santa Fe, NM 87501 USA. Smithsonian Inst, Dept Paleobiol, Washington, DC 20560 USA. RP Newman, MEJ (reprint author), Santa Fe Inst, 1399 Hyde Pk Rd, Santa Fe, NM 87501 USA. NR 34 TC 23 Z9 24 U1 1 U2 5 PU PALEONTOLOGICAL SOC INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044 USA SN 0094-8373 J9 PALEOBIOLOGY JI Paleobiology PD FAL PY 1999 VL 25 IS 4 BP 434 EP 439 PG 6 WC Biodiversity Conservation; Ecology; Evolutionary Biology; Paleontology SC Biodiversity & Conservation; Environmental Sciences & Ecology; Evolutionary Biology; Paleontology GA 265KX UT WOS:000084244400002 ER PT J AU Chung, HK Kirby, K Babb, JF AF Chung, HK Kirby, K Babb, JF TI Theoretical study of the absorption spectra of the lithium dimer SO PHYSICAL REVIEW A LA English DT Article ID TRANSITION DIPOLE-MOMENT; EXCITED-STATES; ALKALI DIMERS; GROUND-STATE; LYING STATES; BAND SYSTEM; LI-2; ATOMS; DISPERSION; LI2 AB For the lithium dimer we calculate cross sections for absorption of radiation from:the vibrational-rotational levels of the ground X (1)Sigma(g)(+) electronic state to the vibrational levels and continua of the excited A (1)Sigma(u)(+) and B (1)Pi(u) electronic states. Theoretical and experimental data are used to characterize the molecular properties taking advantage of knowledge recently obtained from photoassociation spectroscopy and ultra-cold atom collision studies. The quantum-mechanical calculations are carried out for temperatures in the range from 1000 to 2000 K and are compared with previous calculations and measurements where available. [S1050-2947(99)01109-9]. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Chung, HK (reprint author), Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, 60 Garden St, Cambridge, MA 02138 USA. OI Babb, James/0000-0002-3883-9501 NR 43 TC 22 Z9 22 U1 2 U2 8 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD SEP PY 1999 VL 60 IS 3 BP 2002 EP 2008 DI 10.1103/PhysRevA.60.2002 PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 235YF UT WOS:000082570900037 ER PT J AU Cote, R Dalgarno, A Lyyra, AM Li, L AF Cote, R Dalgarno, A Lyyra, AM Li, L TI Observation of a shape resonance in the a (3)Sigma(+)(u) state of Li-7(2) SO PHYSICAL REVIEW A LA English DT Article ID LOWEST-LYING STATES; SPECTROSCOPY AB Using the most accurate potential curves available for the a (3)Sigma(u)(+) and X (1)Sigma(g)(+) states of lithium molecules, we compute the positions of shape resonances. We also calculate the deexcitation probability from a bound level upsilon' with rotational number N' to the continuum of the lower state, and conclude that a shape resonance should be measurable for the transition 2 (3)Pi(g) --> a (3)Sigma(u)(+). Such a shape resonance has been identified from the spectra of the transition from the upsilon' = 2,N' = 4 level of 2 (3)Pi(g) into the N " = 4 continuum of a (3)Sigma(u)(+). Its position is in good agreement with the theoretical prediction. [S1050-2947(99)09909-6]. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. Temple Univ, Dept Phys, Philadelphia, PA 19122 USA. Tsing Hua Univ, Dept Modern Appl Phys, Beijing 100084, Peoples R China. RP Cote, R (reprint author), Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, 60 Garden St, Cambridge, MA 02138 USA. NR 15 TC 15 Z9 15 U1 3 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD SEP PY 1999 VL 60 IS 3 BP 2063 EP 2068 DI 10.1103/PhysRevA.60.2063 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 235YF UT WOS:000082570900044 ER PT J AU Jonsell, S Saenz, A Froelich, P AF Jonsell, S Saenz, A Froelich, P TI Neutrino-mass determination from tritium beta decay: Corrections to and prospects of experimental verification of the final-state spectrum SO PHYSICAL REVIEW C LA English DT Article ID ANTINEUTRINO REST MASS; ELECTRONIC RESONANCES; MOLECULAR TRITIUM; LASER-ABSORPTION; HEH+; ION; T-2; PREDISSOCIATION; DISSOCIATION; EXCITATIONS AB We have investigated the final-state spectrum of HeT+ and HeH+ following beta decay of T-2 or TH. For the electronically bound-state part of the spectrum the effects of a corrected recoil, improved potential curves for the excited states, nonadiabatic effects, and excitations of the initial molecular state have been investigated. We also discuss the feasibility of various experimental methods to verify the theoretical final-state spectrum. [S0556-2813(99)02808-3]. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. Uppsala Univ, Dept Quantum Chem, S-75120 Uppsala, Sweden. Max Planck Inst Quantum Opt, D-85748 Garching, Germany. RP Jonsell, S (reprint author), Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, 60 Garden St, Cambridge, MA 02138 USA. RI Jonsell, Svante/J-2251-2016 OI Jonsell, Svante/0000-0003-4969-1714 NR 45 TC 15 Z9 15 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD SEP PY 1999 VL 60 IS 3 AR 034601 DI 10.1103/PhysRevC.60.034601 PG 12 WC Physics, Nuclear SC Physics GA 238VM UT WOS:000082735100030 ER PT J AU Kawamura, JH Hunter, TR Tong, CYE Blundell, R Zhang, Q Katz, CA Papa, DC Sridharan, TK AF Kawamura, JH Hunter, TR Tong, CYE Blundell, R Zhang, Q Katz, CA Papa, DC Sridharan, TK TI First image with the CfA superconductive HEB receiver: The protostellar outflow from IRAS 20126+4104 in CO (J=7-6) SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article ID H-II REGIONS; ANGULAR-RESOLUTION CAMERA; MOLECULAR OUTFLOWS; STAR-FORMATION; SUBMILLIMETER; EMISSION; TRANSITION; NIOBIUM; CLOUDS; DESIGN AB We present a spectral line image in CO (J = 7-6) of the spatially compact molecular outflow from the massive protostar IRAS 20126+4014, observed using a novel superconductive hot-electron bolometer (HEB) heterodyne receiver we recently installed at the 10 m Heinrich Hertz Telescope. The bipolar outflow is clearly detected and resolved with a center of symmetry situated at the position of the massive protostar, previously identified as an IRAS source and a millimeter continuum source. The peaks of the emission from the red- and blueshifted CO lobes are separated by approximate to 14 " (0.1 pc), and the velocity of the CO emission extends +/-30 km s(-1) from the ambient cloud velocity. The total outflowing gas mass is approximately 4 M., while the outflow rate is at least 6 x 10(-4) M. yr(-1). Both high-velocity CO emission maxima trail the NH3 (3, 3) and SiO clumps located 3 "-4 " downstream (farther from the IR source) in the flow. The high-excitation CO line and the NH3 are likely tracing the heated gas entrained in different parts of the bow shocks. By interpreting our observations in terms of a jet-driven model, we estimate the density in the underlying jet to be at least 10(5) cm(-3). The outflow appears much more compact and in a different orientation than the arcminute-scale north/south flow seen in low-J transitions of CO. These observations represent the first successful operation of a superconductive HEB receiver on a telescope and demonstrate the importance of high-frequency submillimeter lines to the understanding of the protostellar environment. C1 CALTECH, Pasadena, CA 91125 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Kawamura, JH (reprint author), CALTECH, MS 320-47, Pasadena, CA 91125 USA. OI Tong, Edward/0000-0002-7736-4203 NR 41 TC 19 Z9 19 U1 0 U2 1 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 SEP PY 1999 VL 111 IS 763 BP 1088 EP 1094 DI 10.1086/316419 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 234MU UT WOS:000082489100002 ER PT J AU Jiang, QH Piperno, DR AF Jiang, QH Piperno, DR TI Environmental and archaeological implications of a Late Quaternary palynological sequence, Poyang Lake, southern China SO QUATERNARY RESEARCH LA English DT Article ID YANGTZE AB Paleoecological data from Poyang Lake, southern China, indicate that significant natural and human-induced vegetational changes have occurred during the Late Quaternary in the Middle Yangtze River valley, the likely location of rice (Oryza sativa L.) domestication. During the late Pleistocene (from ca. 12,830 to ca. 10,500 yr B.P.), the climate was cooler and drier than today's. The subtropical, mixed deciduous-evergreen broad-leaved forest which constitutes the modern, potential vegetation was reduced and herbaceous vegetative cover expanded. A hiatus in sedimentation occurred in Poyang Lake, beginning sometime after ca. 10,500 yr B.P. and lasting until the middle Holocene (ca. 4000 yr B.P.). At ca. 4000 yr B.P., the regional vegetation was a diverse, broad-leaved forest dominated by many of the same arboreal elements (e.g., Quercus, Castanopsis, Liquidambar) that grow in the area today. A significant reduction of arboreal pollen and an increase of herbaceous pollen at ca. 2000 yr B.P. probably reflect human influence on the vegetation and the expansion of intensive rice agriculture into the dryland forests near the river valleys. (C) 1999 University of Washington. C1 Smithsonian Trop Res Inst, Ctr Trop Paleoecol & Archaeol, Balboa, Panama. RP Piperno, DR (reprint author), Smithsonian Trop Res Inst, Ctr Trop Paleoecol & Archaeol, Balboa, Panama. NR 30 TC 37 Z9 42 U1 0 U2 2 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0033-5894 J9 QUATERNARY RES JI Quat. Res. PD SEP PY 1999 VL 52 IS 2 BP 250 EP 258 DI 10.1006/qres.1999.2070 PG 9 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 235ZG UT WOS:000082573300013 ER PT J AU Kalfatovic, MR AF Kalfatovic, MR TI Critical companions to popular contemporary writers. SO REFERENCE & USER SERVICES QUARTERLY LA English DT Book Review C1 Smithsonian Inst Lib, Washington, DC 20560 USA. RP Kalfatovic, MR (reprint author), Smithsonian Inst Lib, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER LIBRARY ASSOC PI CHICAGO PA 50 E HURON ST, CHICAGO, IL 60611 USA SN 1094-9054 J9 REF USER SERV Q JI Ref. User Serv. Q. PD FAL PY 1999 VL 39 IS 1 BP 84 EP 85 PG 2 WC Information Science & Library Science SC Information Science & Library Science GA 265CT UT WOS:000084224200011 ER PT J AU Omland, KE AF Omland, KE TI The assumptions and challenges of ancestral state reconstructions SO SYSTEMATIC BIOLOGY LA English DT Article ID CHARACTER STATES; EVOLUTION; PHYLOGENIES; LIKELIHOOD; HYPOTHESES; PARSIMONY; HISTORY; BIAS; TREE C1 Univ Minnesota, James Ford Bell Museum Nat Hist, St Paul, MN 55108 USA. Univ Minnesota, Dept Ecol Evolut & Behav, St Paul, MN 55108 USA. RP Omland, KE (reprint author), Smithsonian Inst, Natl Zool Pk, Genet Lab, 3001 Connecticut Ave NW, Washington, DC 20008 USA. RI Omland, Kevin/A-8887-2010 OI Omland, Kevin/0000-0002-3863-5509 NR 51 TC 85 Z9 87 U1 0 U2 9 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 1063-5157 J9 SYST BIOL JI Syst. Biol. PD SEP PY 1999 VL 48 IS 3 BP 604 EP 611 DI 10.1080/106351599260175 PG 8 WC Evolutionary Biology SC Evolutionary Biology GA 244DZ UT WOS:000083037700010 ER PT J AU Schultz, TR Churchill, GA AF Schultz, TR Churchill, GA TI The role of subjectivity in reconstructing ancestral character states: A Bayesian approach to unknown rates, states, and transformation asymmetries SO SYSTEMATIC BIOLOGY LA English DT Article ID PROTEIN SEQUENCES; TREES; PHYLOGENIES; LIKELIHOOD; PARSIMONY C1 Smithsonian Inst, Natl Museum Nat Hist, Dept Entomol, Washington, DC 20560 USA. Jackson Lab, Bar Harbor, ME 04609 USA. Cornell Univ, Dept Plant Breeding & Biometry, Ithaca, NY 14853 USA. RP Schultz, TR (reprint author), Smithsonian Inst, Natl Museum Nat Hist, Dept Entomol, MRC 165, Washington, DC 20560 USA. NR 27 TC 68 Z9 69 U1 0 U2 8 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 1063-5157 J9 SYST BIOL JI Syst. Biol. PD SEP PY 1999 VL 48 IS 3 BP 651 EP 664 PG 14 WC Evolutionary Biology SC Evolutionary Biology GA 244DZ UT WOS:000083037700015 ER PT J AU Brooks, R Jennions, MD AF Brooks, R Jennions, MD TI The dark side of sexual selection SO TRENDS IN ECOLOGY & EVOLUTION LA English DT Editorial Material ID DROSOPHILA-MELANOGASTER; CONFLICT; ECOLOGY; COST C1 James Cook Univ N Queensland, Sch Trop Biol, Townsville, Qld 4811, Australia. Smithsonian Trop Res Inst, Balboa, Panama. RP Brooks, R (reprint author), James Cook Univ N Queensland, Sch Trop Biol, Townsville, Qld 4811, Australia. RI Brooks, Robert/A-1251-2008; Jennions, Michael/C-7560-2009 OI Brooks, Robert/0000-0001-6926-0781; Jennions, Michael/0000-0001-9221-2788 NR 14 TC 15 Z9 16 U1 1 U2 12 PU ELSEVIER SCIENCE LONDON PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 0169-5347 J9 TRENDS ECOL EVOL JI Trends Ecol. Evol. PD SEP PY 1999 VL 14 IS 9 BP 336 EP 337 DI 10.1016/S0169-5347(99)01689-4 PG 2 WC Ecology; Evolutionary Biology; Genetics & Heredity SC Environmental Sciences & Ecology; Evolutionary Biology; Genetics & Heredity GA 222JP UT WOS:000081781400003 ER PT J AU Lamirande, EW Nichols, DK Owens, JW Gaskin, JM Jacobson, ER AF Lamirande, EW Nichols, DK Owens, JW Gaskin, JM Jacobson, ER TI Isolation and experimental transmission of a reovirus pathogenic in ratsnakes (Elaphe species) SO VIRUS RESEARCH LA English DT Article; Proceedings Paper CT 4th International Symposium on Viruses of Lower Vertebrates CY MAY 12-15, 1998 CL WEYMOUTH LAB, WEYMOUTH, ENGLAND HO WEYMOUTH LAB DE Elaphe sp.; pneumonia; reovirus; snake; tracheitis ID VIRUS; PNEUMONIA; SNAKE AB A reovirus was isolated from juvenile Moellendorff's ratsnakes (Elaphe moellendorffi) and beauty snakes (Elaphe taenuris) that died soon after importation into the USA. Viper heart (VH2) cells inoculated with tissue homogenates showed cytopathic effects consisting of large syncytia formation followed by cell detachment from the monolayer. Tissue culture supernatants failed to hemagglutinate guinea pig and chicken erythrocytes at room temperature. Electron microscopy of purified virions revealed spherical to icosahedral particles measuring 70-85 nm in diameter with a double capsid layer. Preparations of the viral genome contained ten segments of dsRNA when analyzed by polyacrylamide gel electrophoresis. A juvenile black ratsnake (Elaphe obsoleta obsaleta) was experimentally inoculated with the isolate and was found dead 26 days post inoculation. Necropsy revealed diffuse subacute interstitial pneumonia with respiratory epithelial cell hyperplasia and syncytia. Reovirus isolated from this snake was used to inoculate another juvenile black ratsnake which was euthanized 40 days post inoculation. Pneumonia and multifocal subacute proliferative tracheitis were found on necropsy. Reovirus was isolated from the lung of this snake and was demonstrated by transmission electron microscopy. This is the first documentation of a pathogenic reptile reovirus and the first report of experimental transmission of a reovirus in snakes. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Smithsonian Inst, Natl Zool Pk, Dept Pathol, Washington, DC 20008 USA. NIH, Vet Resources Program, Off Res Serv, Bethesda, MD 20892 USA. Univ Florida, Coll Vet Med, Dept Pathobiol, Gainesville, FL 32610 USA. Univ Florida, Coll Vet Med, Dept Small Anim Clin Sci, Gainesville, FL 32610 USA. RP Lamirande, EW (reprint author), Smithsonian Inst, Natl Zool Pk, Dept Pathol, Washington, DC 20008 USA. NR 14 TC 31 Z9 38 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-1702 J9 VIRUS RES JI Virus Res. PD SEP PY 1999 VL 63 IS 1-2 BP 135 EP 141 DI 10.1016/S0168-1702(99)00067-2 PG 7 WC Virology SC Virology GA 238PB UT WOS:000082717700017 PM 10509725 ER PT J AU Viola, HJ AF Viola, HJ TI Tecumseh: A life SO WESTERN HISTORICAL QUARTERLY LA English DT Book Review C1 Smithsonian Inst, Washington, DC 20560 USA. RP Viola, HJ (reprint author), Smithsonian Inst, Washington, DC 20560 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU WESTERN HISTORY ASSOCIATION PI LOGAN PA UTAH STATE UNIV, UMC 0740, LOGAN, UT 84322 USA SN 0043-3810 J9 WESTERN HIST QUART JI West. Hist. Q. PD FAL PY 1999 VL 30 IS 3 BP 394 EP 395 DI 10.2307/971404 PG 2 WC History SC History GA 232AC UT WOS:000082342700032 ER PT J AU Whigham, DF Lee, LC Brinson, MM Rheinhardt, RD Rains, MC Mason, JA Kahn, H Ruhlman, MB Nutter, WL AF Whigham, DF Lee, LC Brinson, MM Rheinhardt, RD Rains, MC Mason, JA Kahn, H Ruhlman, MB Nutter, WL TI Hydrogeomorphic (HGM) assessment - A test of user consistency SO WETLANDS LA English DT Article DE hydrogeomorphic approach; HGM; riverine wetlands; reference wetlands; test of user consistency; Maryland; Virginia; Delaware ID CHICKAHOMINY RIVER; WETLANDS; VIRGINIA; FORESTS; VEGETATION AB We describe the first test conducted to determine user consistency in the application of hydrogeomorphic (HGM) functional assessment models. Over a three-week period, two teams of individuals trained in the HGM methodology assessed 44 riverine wetlands on the Coastal Plain of Delaware, Maryland, and Virginia, USA. Results demonstrated a high degree of agreement between the two assessment teams for both Variable Subindices and Functional Capacity Index Scores, indicating that the assessment models were robust and results were repeatable. Analyses of the data demonstrated the importance of only using variables whose measurements are repeatable. When variable measurements are not repeatable, HGM functional capacity scores are detrimentally affected, especially functions that are modeled by only a few variables. C1 Smithsonian Environm Res Ctr, Edgewater, MD 21027 USA. RP Whigham, DF (reprint author), Smithsonian Environm Res Ctr, POB 28, Edgewater, MD 21027 USA. OI Whigham, Dennis/0000-0003-1488-820X NR 32 TC 6 Z9 6 U1 1 U2 6 PU SOC WETLAND SCIENTISTS PI LAWRENCE PA 810 E TENTH ST, P O BOX 1897, LAWRENCE, KS 66044 USA SN 0277-5212 J9 WETLANDS JI Wetlands PD SEP PY 1999 VL 19 IS 3 BP 560 EP 569 PG 10 WC Ecology; Environmental Sciences SC Environmental Sciences & Ecology GA 237VK UT WOS:000082677100008 ER PT J AU Young, KE Garza, V Snowden, K Dobson, RJ Powell, D Craig, TM AF Young, KE Garza, V Snowden, K Dobson, RJ Powell, D Craig, TM TI Parasite diversity and anthelmintic resistance in two herds of horses SO VETERINARY PARASITOLOGY LA English DT Article; Proceedings Paper CT Conference on Equine Cyathostomes CY NOV 07-08, 1998 CL UNIV GEORGIA, ATHENS, GEORGIA SP Univ Georgia, State Art Conf Program, Fort Dodge Anim Hlth, Hoechst Roussel Vet, Merial Ltd, Pfizer Anim Hlth HO UNIV GEORGIA DE Hone nematodes; anthelmintic resistance ID EQUINE SMALL STRONGYLES; BENZIMIDAZOLE-RESISTANCE; FIELD-EVALUATION; SHEEP; CYATHOSTOMES; IVERMECTIN; NEMATODES AB Diversity of parasite populations was compared between two herds of horses, one a regularly treated herd the other a feral herd which has bad no anthelmintic treatment for at least 25 years. Eggs obtained from fecal samples of both herds were tested for anthelmintic resistance by use of an in-vitro larval hatch/development assay (LDA), DrenchRite(TM). A fecal egg reduction test was also performed with the domesticated herd using fenbendazole, pyrantel pamoate and ivermectin. Cyathostomes were the predominant group of worms present in both herds. Trichostrongylus axei was seen in both herds, but Strongylus equinus, Strongylus vulgaris, Gyalocephalus capitatus, Poteriostomum spp, and Strongyloides westeri were only found in the feral horses. Larvae of Strongylus edentatus were found in a single domesticated horse. Fecal egg reduction tests with the domesticated herd showed a 32% egg count reduction for fenbendazole, a 93% reduction with pyrantel, and a 99% reduction with ivermectin. From the LDA, anthelmintic resistance was evaluated by determining the resistance ratio of the domesticated herd compared with the feral herd. For benzimidazoles in the domesticated herd, 45% of the cyathostome population was 9.4 times more tolerant than the feral herd's parasite population. The parasite population in the domesticated herd was 1.5 times more tolerant to Levamisole, and 1.7 times more tolerant to the benzimidazole-levamisole combination than the parasite population within the feral herd. 9% of the parasite population in the domesticated herd was 90 times more tolerant to avermectins than the feral herd's parasite population, even though a subpopulation of worms in the feral herd were tolerant to low concentrations of avermectins despite never being previously exposed to this class of anthelmintic. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Texas A&M Univ, Dept Vet Pathobiol, College Stn, TX 77843 USA. CSIRO, Mcmaster Lab, Blacktown, NSW 2148, Australia. Univ Maryland, Dept Biol, College Pk, MD 20742 USA. Smithsonian Inst, Natl Zool Pk, Dept Zool Res, Washington, DC 20008 USA. RP Craig, TM (reprint author), Texas A&M Univ, Dept Vet Pathobiol, College Stn, TX 77843 USA. RI Snowden, Karen/C-9111-2013 NR 33 TC 34 Z9 35 U1 3 U2 18 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-4017 J9 VET PARASITOL JI Vet. Parasitol. PD AUG 31 PY 1999 VL 85 IS 2-3 BP 205 EP 214 DI 10.1016/S0304-4017(99)00100-4 PG 10 WC Parasitology; Veterinary Sciences SC Parasitology; Veterinary Sciences GA 229ZA UT WOS:000082225100020 PM 10485366 ER PT J AU Bulmer, MH Wilson, JB AF Bulmer, MH Wilson, JB TI Comparison of flat-topped stellate seamounts on Earth's seafloor with stellate domes on Venus using side-scan sonar and Magellan synthetic aperture radar SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article DE seamounts; Earth; domes; Venus; side-scanning methods ID EAST PACIFIC RISE; PANCAKE DOMES; VOLCANIC EDIFICES; 15-DEGREES-S; 19-DEGREES-S; EMPLACEMENT; BATHYMETRY; SHAPES; GROWTH; FLANKS AB The diameters of many domes on Venus imaged by the Magellan synthetic aperture radar (SAR) are an order of magnitude larger than terrestrial subaerial domes, however, surveys of the seafloor using sonar imaging systems such as GLORIA (Geological Long Range Inclined Asdic) and SeaBEAM have revealed flat-topped volcanic features with similar diameters, volumes and slope angles. Suggested analogies beta een domes on Venus and seamounts on the northern East Pacific Rise and off Hawaii have been tested by D,K. Smith [J. Volcanol. Geotherm. Res. 73 (1996) 47-64] using comparisons of size and shape and significant differences identified. GLORIA images of flat-topped seamounts near Hawaii show them to have stellate planforms, Over half of the total population of 375 domes on Venus have been modified and many have stellate planforms. We have focused on the similarities in stellate planforms between flat-topped seamounts and modified domes on Venus. We have used GLORIA sonar and Magellan radar data to constrain the formation and evolution of both flat-topped seamounts on the ocean floor and volcanic domes on Venus to see if the processes that formed them are similar. We propose that flat-topped seamounts on the Hawaiian Ridge are built on sediments overlying the oceanic crust and that available evidence supports three processes that can form stellate margins: (1) radial dike intrusions related to flank rift zones, (2) dike intrusions which cause slope failures: and (3) gravitational slope failures unrelated to intrusions. For Venus, where low erosion rates and the absence of a sediment layer results in lavas being emplaced directly onto the crust, the available evidence supports stellate margins originating by gravitational slope failures unrelated to diking, though intrusions cannot be ruled out with existing data. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Smithsonian Inst, Natl Air & Space Museum, Ctr Earth & Planetary Studies, Washington, DC 20560 USA. Univ London, Royal Holloway & Bedford New Coll, Dept Geol, Egham TW20 0EX, Surrey, England. RP Bulmer, MH (reprint author), Smithsonian Inst, Natl Air & Space Museum, Ctr Earth & Planetary Studies, Washington, DC 20560 USA. NR 50 TC 7 Z9 8 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0012-821X J9 EARTH PLANET SC LETT JI Earth Planet. Sci. Lett. PD AUG 30 PY 1999 VL 171 IS 2 BP 277 EP 287 DI 10.1016/S0012-821X(99)00154-5 PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 229FU UT WOS:000082183500007 ER PT J AU Esry, BD Greene, CH Burke, JP AF Esry, BD Greene, CH Burke, JP TI Recombination of three atoms in the ultracold limit SO PHYSICAL REVIEW LETTERS LA English DT Article ID BOSE-EINSTEIN CONDENSATION; SCATTERING; DECAY; GASES AB We identify two qualitatively different mechanisms that control three-body recombination in a spin-polarized gas near zero temperature. A universal curve describes the recombination rate versus the two-body scattering length a. It grows as a(4) for large \a\. with different mechanisms for a < 0 and a > 0. Our calculations document a previously established mechanism that causes K-3 to grow rapidly as the two-body scattering length a increases toward +infinity, and a new tunneling mechanism that produces an even stronger enhancement of K-3 as a --> -infinity. The expectations based on these two mechanisms can be modified by quantum mechanical interference or resonance effects. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. Univ Colorado, Dept Phys, Boulder, CO 80309 USA. Univ Colorado, JILA, Boulder, CO 80309 USA. RP Esry, BD (reprint author), Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RI Greene, Chris/C-3821-2011; Esry, Brett/H-7511-2013 OI Greene, Chris/0000-0002-2096-6385; Esry, Brett/0000-0003-3207-8526 NR 27 TC 309 Z9 310 U1 0 U2 12 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 AUG 30 PY 1999 VL 83 IS 9 BP 1751 EP 1754 DI 10.1103/PhysRevLett.83.1751 PG 4 WC Physics, Multidisciplinary SC Physics GA 230GC UT WOS:000082242600013 ER PT J AU Jamieson, MJ AF Jamieson, MJ TI Adiabatically corrected scattering lengths and effective ranges for collisions of helium atoms SO CHEMICAL PHYSICS LETTERS LA English DT Article ID BINDING-ENERGY; EFIMOV STATES; HE-HE; POTENTIALS; DIMER; RETARDATION; TRIMER AB The accurate relativistically retarded potential of Janzen and Aziz [J. Chem. Phys. 107 (1997) 914] and the adiabatic correction of Komasa et al. [Chem. Phys. Lett. 304 (1999) 293] are used in a calculation of scattering lengths and effective ranges for He-3-He-3, He-3-He-4 and He-4-He-4 collisions; the binding energy and the number of Efimov states of the He-4-He-4 dimer are also presented. (C) 1999 Published by Elsevier Science B.V, All rights reserved. C1 Univ Glasgow, Dept Comp Sci, Glasgow G12 8QQ, Lanark, Scotland. RP Jamieson, MJ (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 23 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD AUG 27 PY 1999 VL 310 IS 1-2 BP 222 EP 224 DI 10.1016/S0009-2614(99)00807-6 PG 3 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 232QA UT WOS:000082380400034 ER PT J AU Watters, TR Robinson, MS AF Watters, TR Robinson, MS TI Lobate scarps and the Martian crustal dichotomy SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID ORBITER LASER ALTIMETER; HEMISPHERIC DICHOTOMY; NORTHERN-HEMISPHERE; VALLES-MARINERIS; THRUST SHEETS; IMPACT BASINS; GIANT IMPACT; MARS; DISPLACEMENT; TOPOGRAPHY AB Landforms reflecting crustal shortening are found in the ancient highlands of the eastern hemisphere of Mars. These structures, referred to as lobate scarps, are interpreted to be thrust faults. Lobate scarpe occur near and are oriented roughly parallel to the Martian crustal dichotomy, a major geologic and topographic boundary that divides the heavily cratered highlands from the relatively smooth, featureless northern lowlands. The long- and short-wavelength topography of lobate scarps in the northern Terra Cimmeria-Amenthes region have been analyzed using photoclinometry, Earth-based radar altimetry, and Mars Orbiter Laser Altimeter data. The measured relief of lobate scarps in this region ranges from similar to 110 to 1230 m, and they occur on gentle regional slopes that dip both toward and away from the dichotomy. Estimates of the horizontal shortening across the lobate scarps studied range from roughly 0.24 to 2.6 km (n = 9), assuming fault plane dips of 25 degrees. The displacement-length (D-L) relationships of thrust faults associated with the lobate scarps are consistent with those observed for terrestrial fault populations. The compressional strain in the heavily cratered highlands near the dichotomy, determined using the D-L data for the lobate scarps, is estimated to be similar to 0.17%. Topographic data indicate that the dichotomy in the northern Terra Cimmeria-Amenthes region has a distinct topographic signature. The spatial and temporal relationship of the lobate scarps to the boundary suggests that they are related to its formation, supporting models for a tectonic origin of the crustal dichotomy. C1 Smithsonian Inst, Natl Air & Space Museum, Ctr Earth & Planetary Studies, Washington, DC 20560 USA. Northwestern Univ, Dept Geol Sci, Evanston, IL 60209 USA. RP Watters, TR (reprint author), Smithsonian Inst, Natl Air & Space Museum, Ctr Earth & Planetary Studies, Washington, DC 20560 USA. NR 59 TC 32 Z9 32 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-PLANET JI J. Geophys. Res.-Planets PD AUG 25 PY 1999 VL 104 IS E8 BP 18981 EP 18990 DI 10.1029/1998JE001007 PG 10 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 229KG UT WOS:000082193300008 ER PT J AU Mair, RW Wong, GP Hoffmann, D Hurlimann, MD Schwartz, LM Patz, S Walsworth, RL AF Mair, RW Wong, GP Hoffmann, D Hurlimann, MD Schwartz, LM Patz, S Walsworth, RL TI Xenon gas diffusion NMR as a probe of porous media tortuosity. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Schlumberger Doll Res Ctr, Ridgefield, CT 06877 USA. Brigham & Womens Hosp, Dept Radiol MRI Res, Boston, MA 02115 USA. RI Patz, Samuel/I-2879-2012 NR 0 TC 0 Z9 0 U1 0 U2 3 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 AUG 22 PY 1999 VL 218 MA 25-GEOC BP U652 EP U652 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 226QZ UT WOS:000082033901969 ER PT J AU Lovette, IJ Bermingham, E AF Lovette, IJ Bermingham, E TI Explosive speciation in the New World Dendroica warblers SO PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES LA English DT Article DE speciation; adaptive radiation; sexual selection; phylogeny; mitochondrial DNA; Dendroica ID AMERICAN WOOD WARBLERS; NORTH-AMERICAN; CICHLID FISHES; LAKE VICTORIA; EVOLUTION; PLEISTOCENE; FOREST; BIRDS; DIVERSIFICATION; BIOGEOGRAPHY AB The 27 species of Dendroica wood-warblers represent North America's most spectacular avian adaptive radiation. Dendroica species exhibit high levels of local sympatry and differ in plumage and song, but the group contrasts with other well-known avian adaptive radiations such as the Hawaiian honeycreepers and Galapagos finches in that Dendroica species have differentiated modestly in morphometric traits related to foraging. Instead, sympatric Dendroica tend to partition resources behaviourally and they have become a widely cited example of competitive exclusion. We explored the temporal structure of Dendroica diversification via a phylogeny based on 3639 nucleotides of protein-coding mitochondrial DNA(mtDNA). The taxa sampled included 60 individuals representing 24 Dendroica species and a variety of other paruline warbler and outgroup species. Mitochondrial divergences among Dendroica species were generally large (mean pairwise interspecific distances, 10.0%) and many species were rooted in a basal polytomy. The prevalence of long terminal branches indicates that these species have evolved efficient isolating mechanisms that have prevented mtDNA introgression despite the many opportunities for hybridization resulting from local sympatry. Comparisons with a null model of random bifurcation- extinction demonstrate that cladogenesis in Dendroica has been clustered non-randomly with respect to time, with a significant burst of speciation occurring early in the history of the genus, possibly as long ago as the Late Miocene or Early Pliocene periods. Although this non-random clustering of speciation is consistent with the pattern expected of an adaptive radiation, the age of the Dendroica radiation suggests it is an 'ancient species flock' in which most extant species represent lineages that have long been evolutionarily independent. C1 Smithsonian Trop Res Inst, Unit 0948, APO, AA 34002 USA. Univ Penn, Dept Biol, Philadelphia, PA 19104 USA. RP Lovette, IJ (reprint author), Smithsonian Trop Res Inst, Unit 0948, APO, AA 34002 USA. EM ilovette@sas.upenn.edu RI Lovette, Irby/P-3477-2014 NR 46 TC 132 Z9 137 U1 2 U2 31 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 0962-8452 J9 P ROY SOC B-BIOL SCI JI Proc. R. Soc. B-Biol. Sci. PD AUG 22 PY 1999 VL 266 IS 1429 BP 1629 EP 1636 PG 8 WC Biology; Ecology; Evolutionary Biology SC Life Sciences & Biomedicine - Other Topics; Environmental Sciences & Ecology; Evolutionary Biology GA 228CF UT WOS:000082118200004 ER PT J AU Markevitch, M Sarazin, CL Vikhlinin, A AF Markevitch, M Sarazin, CL Vikhlinin, A TI Physics of the merging clusters cygnus A, A3667, and A2065 SO ASTROPHYSICAL JOURNAL LA English DT Article DE cooling flows; galaxies : clusters : individual (Cygnus A, Abell 2065, Abell 3667) intergalactic medium; X-rays : galaxies ID GALAXIES; ABELL-754 AB We present ASCA gas temperature maps of the nearby merging galaxy clusters Cygnus A, A3667, and A2065. Cygnus A appears to have a particularly simple merger geometry that allows an estimate of the subcluster collision velocity from the observed temperature variations. We estimate it to be similar to 2000 km s(-1). Interestingly, this is similar to the free-fall velocity that the two Cygnus A subclusters should have achieved at the observed separation, suggesting that the merger has been effective in dissipating the kinetic energy of gas halos into thermal energy, without channeling its major fraction elsewhere (e.g., into turbulence). In A3667 we may be observing a spatial lag between the shock front seen in the X-ray image and the corresponding rise of the electron temperature. A lag of the order of hundreds of kilo-parsecs is possible because of the combination of thermal conduction and a finite electron-ion equilibration time. Forthcoming better spatial resolution data will allow a direct measurement of these phenomena in the cluster gas using such lags. A2065 has gas density peaks coincident with two central galaxies. A merger with the collision velocity estimated from the temperature map should have swept away such peaks if the subcluster total mass distributions had hat cores in the centers. The fact that the peaks have survived (or quickly reemerged) suggests that the gravitational potential is also strongly peaked. Finally, the observed specific entropy variations in A3667 and Cygnus A indicate that energy injection from a single major merger may be of the order of the full thermal energy of the gas. We hope that these order-of-magnitude estimates will encourage further work on hydrodynamic simulations, as well as a more quantitative representation of the simulation results, in anticipation of the Chandra and XMM data. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Russian Acad Sci, Inst Space Res, Moscow, Russia. Univ Virginia, Dept Astron, Charlottesville, VA 22903 USA. RP Markevitch, M (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 31 TC 103 Z9 103 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 AUG 20 PY 1999 VL 521 IS 2 BP 526 EP 530 DI 10.1086/307598 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 226JX UT WOS:000082017800004 ER PT J AU Evans, I Koratkar, A Allen, M Dopita, M Tsvetanov, Z AF Evans, I Koratkar, A Allen, M Dopita, M Tsvetanov, Z TI The excitation mechanism of emission-line regions in Seyfert galaxies SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : individual (NGC 5643, NGC 5728); galaxies : Seyfert; ultraviolet : galaxies ID OPTIMALLY EMITTING CLOUDS; CENTAURUS-A; ULTRAVIOLET; EXTINCTION; FILAMENTS AB We present Hubble Space Telescope UV/optical spectrophotometry and ground-based optical spectrophotometry of the brightest knots in the emission-line regions of the Seyfert galaxies NGC 5643 and NGC 5728. These objects have ionization cones, radio and soft X-ray emission, and evidence of nuclear outflows and winds, suggesting that shocks may be associated with the emission-line gas. Comparison of the UV/optical data with grids of ionization-bounded and mixed ionization- and matter-bounded photoionization models, and shock models with and without ionized precursors, are used to determine whether radiative shocks that photoionize the shock precursor material ("autoionizing shocks") are a significant excitation mechanism for the emission-line gas in these objects. Although the UV/optical spectra studied here are generally compatible with both photoionization and shock + precursor models, an unambiguous shock + precursor signature is not present. This suggests that mechanical energy input may not play the same dominant role in exciting these objects with weak radio jets as appears to be the case in strong radio jet sources such as M87. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Australian Natl Univ, Mt Stromlo & Siding Spring Observ, Weston, ACT 2611, Australia. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. RP Evans, I (reprint author), Smithsonian Astrophys Observ, 60 Garden St,MS-27, Cambridge, MA 02138 USA. RI Dopita, Michael/P-5413-2014 OI Dopita, Michael/0000-0003-0922-4986 NR 19 TC 28 Z9 28 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 AUG 20 PY 1999 VL 521 IS 2 BP 531 EP 546 DI 10.1086/307570 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 226JX UT WOS:000082017800005 ER PT J AU Bower, GC Backer, DC Zhao, JH Goss, M Falcke, H AF Bower, GC Backer, DC Zhao, JH Goss, M Falcke, H TI The linear polarization of Sagittarius A*. I. VLA spectropolarimetry at 4.8 and 8.4 GHz SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; Galaxy : center; polarization; radio continuum : ISM; scattering ID GALACTIC-CENTER; BLACK-HOLE; MODEL; WAVELENGTH; SPECTRUM; SAMPLE; SHOCK; FLUX AB Synchrotron radiation from active galactic nuclei (AGNs) is often highly polarized. We present a search for linear polarization with the Very Large Array (VLA) at 4.8 and 8.4 GHz from the nearest AGN, Sagittarius A*. As a part of this study we used spectropolarimetric data that were sensitive to a rotation measure (RM) as large as 3.5 x 10(6) rad m(-2) at 4.8 GHz and 1.5 x 10(7) rad m(-2) at 8.4 GHz. The upper limit to the linear polarization of Sgr A* over a broad range of RM is 0.2% at both frequencies. We also present continuum observations with the VLA at 4.8 GHz that give an upper limit of 0.1% for RMs less than 10(4) rad m(-2). We conclude that depolarization is unlikely to occur in the Galactic center scattering medium. However, it is possible for depolarization to occur in the accretion region of Sgr A* if the outer scale of turbulence is small enough. We also consider the implications of a very low intrinsic polarization for Sgr A*. C1 Max Planck Inst Radioastron, D-53121 Bonn, Germany. Natl Radio Astron Observ, Socorro, NM 87801 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Univ Calif Berkeley, Radio Astron Lab, Berkeley, CA 94720 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Bower, GC (reprint author), Max Planck Inst Radioastron, Hugel 69, D-53121 Bonn, Germany. RI Falcke, Heino/H-5262-2012 OI Falcke, Heino/0000-0002-2526-6724 NR 23 TC 57 Z9 58 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 AUG 20 PY 1999 VL 521 IS 2 BP 582 EP 586 DI 10.1086/307592 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 226JX UT WOS:000082017800012 ER PT J AU Kalogera, V AF Kalogera, V TI Donor stars in black hole X-ray binaries SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : close; black hole physics; stars : evolution; stars : mass loss; stars : Wolf-Rayet; X-rays : stars ID NEUTRON-STARS; MASS-LOSS; EVOLUTION; OBJECTS; SYSTEMS; PHASE AB We study theoretically the formation of black hole (BH) X-ray binaries. Consistency of the models with the observed relative numbers of systems with low-mass (less than or similar to 2 M.) and intermediate-mass (similar to 2 M.-M-BH) donors leads to severe constraints on the evolutionary parameters of the progenitors. In particular, we find that (1) BH progenitor masses cannot exceed about 2M(BH); (2) high values of the common envelope efficiency parameter (alpha(CE) > 1) are required, implying that energy sources other than orbital contraction must be invoked to eject the envelope; and (3) the mass-loss fraction in helium star winds is limited to less than or similar to 50%. Outside of this limited parameter space for progenitors we find that either BH X-ray binary formation cannot occur at all or donors do not have the full range of observed masses. We discuss the implications of these results for the structure of massive hydrogen-rich stars, the evolution of helium stars, and BH formation. We also consider the possible importance of asymmetric kicks. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM vkalogera@cfa.harvard.edu NR 53 TC 44 Z9 44 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 AUG 20 PY 1999 VL 521 IS 2 BP 723 EP 734 DI 10.1086/307562 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 226JX UT WOS:000082017800028 ER PT J AU Drake, JJ Swartz, DA Beiersdorfer, P Brown, GV Kahn, SM AF Drake, JJ Swartz, DA Beiersdorfer, P Brown, GV Kahn, SM TI On photospheric fluorescence and the nature of the 17.62 angstrom feature in solar X-ray spectra SO ASTROPHYSICAL JOURNAL LA English DT Article DE atomic processes; line : formation; line : identification; Sun : corona; Sun : X-rays, gamma rays ID PHOTOIONIZATION CROSS-SECTIONS; ABUNDANCE; FLARE; IRON; SPECTROMETER; SUN AB The identification of the emission-line feature at 17.62 Angstrom, in solar X-ray spectra is reexamined. Using a Monte Carlo technique, we compute a realistic theoretical upper limit to the observed Fe L alpha photospheric fluorescent line strength caused by irradiation from an overlying corona. These calculations demonstrate that the photospheric Fe L alpha characteristic line is much too weak to account for the observed 17.62 Angstrom, line flux. Instead, we identify this line with the configuration interaction 2s(2)2p(4)3p P-2(3/2)-2s2p(6) S-2(1/2) transition in Fe XVIII seen in Electron Beam Ion Trap spectra and predicted in earlier theoretical work on the Fe XVIII X-ray spectrum. This line should be easily resolved and detected in stellar coronae by the spectrographs on the upcoming Chandra X-ray Observatory, and X-ray Multi-mirror Mission. C1 Harvard Smithsonian Ctr Astrophys, Chandra Xray Ctr, Cambridge, MA 02138 USA. NASA, George C Marshall Space Flight Ctr, Univ Space Res Assoc, Huntsville, AL 35812 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Columbia Univ, Dept Phys, New York, NY 10027 USA. Columbia Univ, Columbia Astrophys Lab, New York, NY 10027 USA. RP Harvard Smithsonian Ctr Astrophys, Chandra Xray Ctr, MS-3,60 Garden St, Cambridge, MA 02138 USA. EM jdrake@cfa.harvard.edu; swartz@avalon.msfc.nasa.gov; beiersdorfer@llnl.gov; brown86@llnl.gov; skahn@astro.columbia.edu NR 28 TC 19 Z9 21 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 AUG 20 PY 1999 VL 521 IS 2 BP 839 EP 843 DI 10.1086/307593 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 226JX UT WOS:000082017800035 ER PT J AU Callanan, PJ Drake, JJ Fruscione, A AF Callanan, PJ Drake, JJ Fruscione, A TI An EUVE observation of the globular cluster M15: The first detection of a low-mass X-ray binary? SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : close; globular clusters : individual (M15); stars : individual (AC 211); X-rays : stars ID EXTREME-ULTRAVIOLET-EXPLORER; SPECTROSCOPY; SPECTRUM; CORE AB We have detected EUV emission from the globular cluster M15 using the Deep Survey Photometer aboard the Extreme Ultraviolet Explorer. The emission is variable at the 97% confidence level. The minimum EUV luminosity implied by our detection is similar to 5 x 10(36) ergs s(-1) for a distance and reddening appropriate to M15. We have examined a number of possible original for this emission including post-asymptotic giant branch stars, a population of hitherto unknown, optically faint, stellar merger products or "supersoft sources," or the well-known M15 low-mass X-ray binary (LMXB) AC 211. A significant EUV flux from AC 211 is supported by the relatively strong He II lambda 4686 emission observed from this system. If the observed EUV flux indeed originates from AC 211, this is the first detection of an LMXB at EUV energies. Furthermore, such a luminosity is comparable to the 2-10 keV X-ray luminosity of AC 211 and may dominate the energetics of the system if absorption local to the binary is taken into account. Further observations of this and other low column LMXBs (e.g., that in NGC 1851) are required to establish the ubiquity of globular cluster/LMXB EUV emission. C1 Natl Univ Ireland Univ Coll Cork, Dept Phys, Cork, Ireland. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Callanan, PJ (reprint author), Natl Univ Ireland Univ Coll Cork, Dept Phys, Cork, Ireland. NR 32 TC 2 Z9 2 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 AUG 20 PY 1999 VL 521 IS 2 BP L125 EP L128 DI 10.1086/312192 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 226KA UT WOS:000082018100012 ER PT J AU Esser, R Sasselov, D AF Esser, R Sasselov, D TI On the disagreement between atmospheric and coronal electron densities SO ASTROPHYSICAL JOURNAL LA English DT Article DE solar wind; Sun : atmosphere; Sun : corona ID SOLAR TRANSITION REGION; ENERGY-BALANCE; HOLE; DIFFUSION; MODELS AB Electron densities in the lower solar atmosphere (photosphere and chromosphere) are derived using a number of different atmospheric models which are constrained by observed spectral lines. Comparing these atmospheric densities to coronal electron densities derived from polarization brightness measurements in the region from about 1.1 to several solar radii, it is shown that there is a discrepancy between the two sets of densities. The atmospheric electron densities are in agreement with a density of maximum 10(7) cm(-3) at 1.1 R.. The polarized brightness densities given in the literature are typically 5 x 10(7) cm(-3) or higher. It is shown that this discrepancy might be due to an overestimation of the coronal electron densities below 1.5-2 R.. C1 Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. RP Esser, R (reprint author), Smithsonian Astrophys Observ, 60 Garden St, Cambridge, MA 02138 USA. NR 23 TC 11 Z9 12 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 AUG 20 PY 1999 VL 521 IS 2 BP L145 EP L148 DI 10.1086/312186 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 226KA UT WOS:000082018100017 ER PT J AU Jayawardhana, R Hartmann, L Fazio, G Fisher, RS Telesco, CM Pinna, RK AF Jayawardhana, R Hartmann, L Fazio, G Fisher, RS Telesco, CM Pinna, RK TI A disk census for the nearest group of young stars: Mid-infrared observations of the TW Hydrae association SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; binaries : general; circumstellar matter; open clusters and associations : individual (TW Hydrae); stars : pre-main-sequence ID TAURI STARS; X-RAY AB A group of young, active stars in the vicinity of TW Hydrae has recently been identified as a possible physical association with a common origin. Given its proximity (similar to 50 pc), age (similar to 10 Myr), and abundance of binary systems, the TW Hya association is ideally suited to studies of the diversity and evolution of circumstellar disks. Here we present mid-infrared observations of 15 candidate members of the group, 11 of which have no previous flux measurements at wavelengths longer than 2 mu m. We report the discovery of a possible 10 mu m excess in CD -33 degrees 7795, which may be due to a circumstellar disk or a faint and as yet undetected binary companion. Of the other stars, only TW Hya, HD 98800, Hen 3-600A, and HR 4796A-all of which were detected by IRAS-show excess thermal emission. Our 10 mu m flux measurements for the remaining members of the association are consistent with photospheric emission, allowing us to rule out dusty inner disks. In light of these findings, we discuss the origin and age of the TW Hya association as well as the implications for disk evolution timescales. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Florida, Dept Astron, Bryant Space Sci Ctr 211, Gainesville, FL 32611 USA. RP Jayawardhana, R (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM rayjay@cfa.harvard.edu NR 25 TC 80 Z9 80 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD AUG 20 PY 1999 VL 521 IS 2 BP L129 EP L132 DI 10.1086/312200 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 226KA UT WOS:000082018100013 ER PT J AU Kalkofen, W Ulmschneider, P Avrett, EH AF Kalkofen, W Ulmschneider, P Avrett, EH TI Does the sun have a full-time chromosphere? SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : chromosphere; Sun : oscillations; waves ID SOLAR CHROMOSPHERE; K-GRAINS; ATMOSPHERE; MODELS; WAVES; CO; OSCILLATIONS; PROPAGATION; DYNAMICS; EMISSION AB The successful modeling of the dynamics of H-2v bright points in the nonmagnetic chromosphere by Carlsson & Stein gave as a by-product a part-time chromosphere lacking the persistent outward temperature increase of time-average empirical models, which is needed to explain observations of UV emission lines and continua. We discuss the failure of the dynamical model to account for most of the observed chromospheric emission, arguing that their model uses only about 1% of the acoustic energy supplied to the medium. Chromospheric heating requires an additional source of energy in the form of acoustic waves of short period (P < 2 minutes), which form shocks and produce the persistent outward temperature increase that can account for the UV emission lines and continua. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Heidelberg Univ, Inst Theoret Astrophys, D-69121 Heidelberg, Germany. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 36 TC 48 Z9 48 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 AUG 20 PY 1999 VL 521 IS 2 BP L141 EP L144 DI 10.1086/312193 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 226KA UT WOS:000082018100016 ER PT J AU Wuethrich, B AF Wuethrich, B TI Speciation - Mexican pairs show geography's role SO SCIENCE LA English DT News Item C1 Smithsonian, Natl Museum Nat Hist, Washington, DC 20560 USA. RP Wuethrich, B (reprint author), Smithsonian, Natl Museum Nat Hist, Washington, DC 20560 USA. NR 0 TC 0 Z9 0 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 AUG 20 PY 1999 VL 285 IS 5431 BP 1190 EP 1190 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 228HC UT WOS:000082130200004 ER PT J AU Gingerich, O AF Gingerich, O TI The pearly gates of cyberspace SO NATURE LA English DT Book Review C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Gingerich, O (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD AUG 19 PY 1999 VL 400 IS 6746 BP 730 EP 730 DI 10.1038/23408 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 228HM UT WOS:000082131100038 ER PT J AU Elosegui, P Davis, JL Gradinarsky, LP Elgered, G Johansson, JM Tahmoush, DA Rius, A AF Elosegui, P Davis, JL Gradinarsky, LP Elgered, G Johansson, JM Tahmoush, DA Rius, A TI Sensing atmospheric structure using small-scale space geodetic networks SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID WATER-VAPOR; GRADIENTS; METEOROLOGY; DELAY AB We describe two ways in which horizontal atmospheric structure affects GPS observations. For a single site, such structure results in azimuthal variations in the atmospheric propagation delay. For a network of sites, the structure will induce an intersite variability in the atmospheric propagation delays. The former effect is more sensitive to high- than low-altitude atmospheric gradients above the site, whereas the latter is insensitive to the altitude of the gradient above the network. This difference in sensitivity can be utilized to probe the local vertical structure of the atmosphere. We demonstrate this technique using GPS data from a small network on the Swedish west coast. We infer for one observing session the presence of a strong horizontal gradient which varies with height. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Inst Estudis Espacials Catalunya, CSIC, Res Unit, E-08034 Barcelona, Spain. Chalmers Univ Technol, Onsala Space Observ, S-43992 Onsala, Sweden. MIT, Haystack Observ, Westford, MA 01886 USA. RP Elosegui, P (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St,MS-42, Cambridge, MA 02138 USA. RI Davis, James/D-8766-2013; Antonio, Rius/A-4873-2012; Elgered, Gunnar/B-7052-2016 OI Davis, James/0000-0003-3057-477X; Antonio, Rius/0000-0002-5947-2649; Elgered, Gunnar/0000-0001-5711-0073 NR 15 TC 19 Z9 20 U1 0 U2 3 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 AUG 15 PY 1999 VL 26 IS 16 BP 2445 EP 2448 DI 10.1029/1999GL900585 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 226GD UT WOS:000082011200010 ER PT J AU Yoshino, K Esmond, JR Parkinson, WH Thorne, AP Learner, RCM Cox, G AF Yoshino, K Esmond, JR Parkinson, WH Thorne, AP Learner, RCM Cox, G TI Fourier transform spectroscopy and cross-section measurements of the Herzberg II bands of O-2 at 295 K SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID HIGH-RESOLUTION; OSCILLATOR-STRENGTHS; ABSORPTION; OXYGEN; ULTRAVIOLET; CONTINUUM; SYSTEM AB Fourier transform spectroscopic measurements of the absorption bands of the Herzberg II (c (1)Sigma(u)(-)-X (3)Sigma(g)(-)) of O-2 at 295 K have been made with a resolution of 0.06 cm(-1) in the wavelength region 240-275 nm. Rotational line positions are determined with an accuracy of 0.005 cm(-1), and rotational term values are presented for the vibrational levels, v(')=6-16. Precise band oscillator strengths of the (7,0)-(16,0) bands are obtained for the first time by direct measurement by summing the cross sections of individual rotational lines of the bands. The rotational line strengths and the branching ratios are also presented for the same bands. (C) 1999 American Institute of Physics. [S0021-9606(99)01531-7]. C1 Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BZ, England. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Yoshino, K (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 19 TC 17 Z9 18 U1 0 U2 1 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 AUG 15 PY 1999 VL 111 IS 7 BP 2960 EP 2967 DI 10.1063/1.479577 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 222GB UT WOS:000081774700014 ER PT J AU Aguirre, A AF Aguirre, A TI Cold big bang nucleogenesis SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology : theory; early universe; nuclear reactions, nucleosynthesis, abundances ID COSMOLOGICAL CONSEQUENCES; ELEMENT PRODUCTION; EARLY UNIVERSE; STARS; ORIGIN AB This paper treats the energetic and nucleosynthetic history of a Friedmann model with low photon-baryon ratio eta(gamma) and positive lepton-baryon ratio eta(L). At early times, such a universe is in equilibrium and is energetically dominated by particle Fermi energies; at later times photon release from elementary particle decays probably lifts degeneracy of nucleons but not of leptons. After outlining the early history I present the results of full nucleosynthesis calculations for nondegenerate baryons and degenerate electrons and neutrinos. The results show that, for eta(gamma) less than or similar to 0.01 (consistent with the particle-decay heating), the neutron-proton ratio depends strongly on eta(L) and that production of sufficient helium to match observations creates large primordial metallicity, in agreement with a previous argument by Carr for the eta(gamma) = 0 case. Excessive metallicity in the cold model is avoided only if eta(L) is sufficiently high (eta(L) > 1.5 for eta(gamma) = 0; eta(L) greater than or similar to 5 for eta(gamma) = 0.01) to suppress all nucleosynthesis before the Population III epoch. The calculations also reveal certain combinations of eta(gamma) greater than or similar to 100 (corresponding to T-0 similar to 0.02) and eta(L) greater than or similar to 5 that produce acceptable helium yields. This result contradicts the widespread notion that astrophysical observations of helium abundance together with nucleosynthesis calculations within a big bang model predict the current radiation background temperature. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Aguirre, A (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 42 TC 7 Z9 7 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 AUG 10 PY 1999 VL 521 IS 1 BP 17 EP 29 DI 10.1086/307534 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 223YC UT WOS:000081868300002 ER PT J AU Macri, LM Huchra, JP Stetson, PB Silbermann, NA Freedman, WL Kennicutt, RC Mould, JR Madore, BF Bresolin, F Ferrarese, L Ford, HC Graham, JA Gibson, BK Han, M Harding, P Hill, RJ Hoessel, JG Hughes, SMG Kelson, DD Illingworth, GD Phelps, RL Prosser, CF Rawson, DM Saha, A Sakai, S Turner, A AF Macri, LM Huchra, JP Stetson, PB Silbermann, NA Freedman, WL Kennicutt, RC Mould, JR Madore, BF Bresolin, F Ferrarese, L Ford, HC Graham, JA Gibson, BK Han, M Harding, P Hill, RJ Hoessel, JG Hughes, SMG Kelson, DD Illingworth, GD Phelps, RL Prosser, CF Rawson, DM Saha, A Sakai, S Turner, A TI The extragalactic distance scale key project. XVIII. The discovery of Cepheids and a new distance to NGC 4535 using the Hubble Space Telescope SO ASTROPHYSICAL JOURNAL LA English DT Article DE Cepheids; distance scale; galaxies : distances and redshifts; galaxies : individual (NGC 4535) ID VIRGO-CLUSTER; SPIRAL GALAXIES; CALIBRATION; CONSTANT; PERFORMANCE; PHOTOMETRY; VARIABLES; WFPC2 AB We report on the discovery of Cepheids in the Virgo spiral galaxy NGC 4535, based on observations made with the Wide Field and Planetary Camera 2 on board the Hubble Space Telescope (HST). NGC 4535 is one of 18 galaxies observed as a part of The HST Key Project on the Extragalactic Distance Scale, which aims to measure the Hubble constant to 10% accuracy. NGC 4535 was observed over 13 epochs using the F555W filter, and over 9 epochs using the F814W filter. The HST F555W and F814W data were transformed to the Johnson V and Kron-Cousins I magnitude systems, respectively. Photometry was performed using two independent programs, DoPHOT and DAOPHOT II/ALLFRAME. Period-luminosity relations in the V and I bands were constructed using 39 high-quality Cepheids present in our set of 50 variable candidates. We obtain a distance modulus of 31.02 +/- 0.26 mag, corresponding kto a distance of 16.0 +/- 1.9 Mpc. Our distance estimate is based on values of mu(0) = 18.50 +/- 0.10 mag and E(V-I) = 0.13 mag for the distance modulus and reddening of the LMC, respectively. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Dominion Astrophys Observ, Victoria, BC V8X 4M6, Canada. CALTECH, IPAC, Pasadena, CA 91125 USA. Carnegie Inst Washington Observ, Pasadena, CA 91101 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Australian Natl Univ, Mt Stromlo & Siding Spring Observ, Weston, ACT 2611, Australia. European So Observ, D-85478 Garching, Germany. CALTECH, Dept Astron, Pasadena, CA 91125 USA. Johns Hopkins Univ, Baltimore, MD 21218 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Carnegie Inst Washington, Dept Terr Magnetism, Washington, DC 20015 USA. Univ Colorado, Ctr Astrophys & Space Astron, Boulder, CO 80309 USA. Avanti Corp, Fremont, CA 94538 USA. Univ Wisconsin, Madison, WI 53706 USA. NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. Univ Calif Santa Cruz, Lick Observ, Santa Cruz, CA 95064 USA. Natl Opt Astron Observ, Tucson, AZ 85726 USA. RP Macri, LM (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Gibson, Brad/M-3592-2015; OI Gibson, Brad/0000-0003-4446-3130; Macri, Lucas/0000-0002-1775-4859 NR 39 TC 54 Z9 54 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 AUG 10 PY 1999 VL 521 IS 1 BP 155 EP 178 DI 10.1086/307541 PN 1 PG 24 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 223YC UT WOS:000081868300014 ER PT J AU Psaltis, D Chakrabarty, D AF Psaltis, D Chakrabarty, D TI The disk-magnetosphere interaction in the accretion-powered millisecond pulsar SAX J11808.4-3658 SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; pulsars : individual (SAX J1808.4-3658); stars : neutron; X-rays : stars ID QUASI-PERIODIC OSCILLATIONS; MAGNETIC NEUTRON-STARS; X-RAY SOURCES; BINARIES; FIELD; VARIABILITY; PULSATIONS; A0535+262; DISCOVERY; OUTBURST AB The recent discovery of the first known accretion-powered millisecond pulsar with the Rossi X-Ray Timing Explorer provides the first direct probe of the interaction of an accretion disk with the magnetic field of a weakly magnetic (B less than or similar to 10(10) C) neutron star. We demonstrate that the presence of coherent pulsations from a weakly magnetic neutron star over a wide range of accretion rates places strong constraints on models of the disk-magnetosphere interaction. We argue that the simple (M) over dot(3/7) scaling law for the Keplerian frequency at the magnetic interaction radius, widely used to model disk accretion onto magnetic stars, is not consistent with observations of SAX J1808.4-3658 for most proposed equations of state for stable neutron stars. We show that the usually neglected effects of multipole magnetic moments, radiation drag forces, and general relativity must be considered when modeling such weakly magnetic systems. Using only very general assumptions, we obtain a robust estimate of mu similar or equal to (1-10) x 10(26) G cm(3) for the dipole magnetic moment of SAX J1808.4-3658, implying a surface dipole field of similar to 10(8)-10(9) C at the stellar equator. We therefore infer that after the end of its accretion phase, this source will become a normal millisecond radio pulsar. Finally, we compare the physical properties of this pulsar with those of the nonpulsing, weakly magnetic neutron stars in low-mass X-ray binaries and argue that the absence of coherent pulsations from the latter does not necessarily imply that these neutron stars have significantly different magnetic field strengths from SAX J1808.4-3658. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. MIT, Ctr Space Res, Cambridge, MA 02139 USA. RP Psaltis, D (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM dpsaltis@cfa.harvard.edu; deepto@space.mit.edu NR 69 TC 119 Z9 119 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD AUG 10 PY 1999 VL 521 IS 1 BP 332 EP 340 DI 10.1086/307525 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 223YC UT WOS:000081868300032 ER PT J AU Haiman, Z Loeb, A AF Haiman, Z Loeb, A TI X-ray emission from the first quasars SO ASTROPHYSICAL JOURNAL LA English DT Article DE black hole physics; cosmology : theory; quasars : general ID HIGH-REDSHIFT GALAXIES; LUMINOSITY FUNCTION; EVOLUTION; UNIVERSE; DENSITY; NUCLEI AB It is currently unknown whether the universe was reionized by quasars or stars at z greater than or similar to 5. We point out that quasars can be best distinguished from stellar systems by their X-ray emission. Based on a simple hierarchical CDM model, we predict the number counts and X-ray fluxes of quasars at high redshifts. The model is consistent with available data on the luminosity function of high-redshift quasars in the optical and soft X-ray bands. The cumulative contribution of faint, undetected quasars in our model is consistent with the unresolved fraction of the X-ray background. We find that the Chandra X-ray Observatory might detect similar to 10(2) quasars from redshifts z greater than or similar to 5 per its 17' x 17' field of view at the flux threshold of similar to 2 x 10(-16) ergs s(-1) cm(-2). The redshifts of these faint point sources could be identified by follow-up infrared observations from the ground or with the Next Generation Space Telescope. C1 NASA, Fermilab Astrophys Ctr, Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Haiman, Z (reprint author), NASA, Fermilab Astrophys Ctr, Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. NR 29 TC 33 Z9 33 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 AUG 10 PY 1999 VL 521 IS 1 BP L9 EP L12 DI 10.1086/312177 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 223YE UT WOS:000081868500003 ER PT J AU Munoz, JA Kochanek, CS Falco, EE AF Munoz, JA Kochanek, CS Falco, EE TI Finding gravitational lenses with X-rays SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology : observations; cosmology : theory; gravitational lensing; quasars : general; X-rays : galaxies ID COSMOLOGICAL CONSTANT; LUMINOSITY FUNCTION; LENSING LIMITS; GALAXIES; MODELS AB Distant galaxies produce similar to 1, 0.1, and 0.01 gravitationally lensed X-ray sources per square degree with soft X-ray fluxes exceeding 10(-15), 10(-14), and 10(-13) ergs s(-1) cm(-2) respectively. These sources will be detected serendipitously with the Chandra X-Ray Observatory at a rate of one to three lenses per year of high-resolution imaging. The low detection rate is due to the small area over which the High Resolution Camera and AXAF CCD Imaging Spectrometer instruments have the smaller than 1." 5 FWHM resolution necessary to find gravitational lenses produced by galaxies. Deep images of rich clusters at intermediate redshifts should yield one wide separation (Delta theta greater than or similar to 5." 0) multiply imaged background X-ray source for every similar to 10, 30, and 300 clusters imaged to the same flux limits. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Munoz, JA (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 34 TC 3 Z9 3 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 AUG 10 PY 1999 VL 521 IS 1 BP L17 EP L20 DI 10.1086/312184 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 223YE UT WOS:000081868500005 ER PT J AU Vikhlinin, A AF Vikhlinin, A TI A method of mass measurement in black hole binaries using timing and high-resolution X-ray spectroscopy SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : spectroscopic; X-rays : general; X-rays : stars ID DYNAMICAL EVIDENCE; CYGNUS-X-1; REFLECTION; PARAMETERS; STAR AB In X-ray binaries, several percent of the compact object luminosity is intercepted by the surface of the normal companion and reradiated through Compton reflection and the K fluorescence. This reflected emission follows the variability of the compact object with a delay approximately equal to the orbital radius divided by the speed of light. This provides the possibility of measuring the orbital radius and thus substantially refining the compact object mass determination compared to using optical data alone. We demonstrate that it may be feasible to measure the time delay between the direct and reflected emission using cross-correlation of the light curves observed near the K alpha line and above the K edge of neutral iron. In the case of Cygnus X-1, the time delay measurement is feasible with a 3 x 10(5)-10(6) s observation by a telescope with a 1000 cm(2) effective area near 6.4 keV and with a similar to 5 eV energy resolution. With longer exposures, it may be possible to obtain mass constraints even if an X-ray source in the binary system lacks an optical counterpart. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Vikhlinin, A (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 25 TC 2 Z9 2 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 AUG 10 PY 1999 VL 521 IS 1 BP L45 EP L48 DI 10.1086/312175 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 223YE UT WOS:000081868500012 ER PT J AU Nakariakov, VM Ofman, L DeLuca, EE Roberts, B Davila, JM AF Nakariakov, VM Ofman, L DeLuca, EE Roberts, B Davila, JM TI TRACE observation of damped coronal loop oscillations: Implications for coronal heating SO SCIENCE LA English DT Article ID RESONANT ABSORPTION; ALFVEN WAVES; SOLAR CORONA; SCALING LAWS; DRIVEN AB The imaging telescope on board the Transition Region and Coronal Explorer (TRACE) spacecraft observed the decaying transversal oscillations of a Long [(130 +/- 6) x 10(6) meters], thin [diameter (2.0 +/- 0.36) x 10(6) meters], bright coronal Loop in the 171 angstrom Fe-IX emission line. The oscillations were excited by a solar flare in the adjacent active region. The decay time of the oscillations is 14.5 +/- 2.7 minutes for an oscillation with a frequency 3.90 +/- 0.13 millihertz, The coronal dissipation coefficient is estimated to be eight to nine orders of magnitude Larger than the theoretically predicted classical value. The larger dissipation coefficient may solve existing difficulties with wave heating and reconnection theories. C1 NASA, Goddard Space Flight Ctr, Raytheon ITSS, Greenbelt, MD 20771 USA. Univ St Andrews, Sch Math & Computat Sci, St Andrews KY16 9SS, Fife, Scotland. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Ofman, L (reprint author), NASA, Goddard Space Flight Ctr, Raytheon ITSS, 682, Greenbelt, MD 20771 USA. RI Nakariakov, Valery/E-2375-2013; DeLuca, Edward/L-7534-2013 OI Nakariakov, Valery/0000-0001-6423-8286; DeLuca, Edward/0000-0001-7416-2895 NR 26 TC 566 Z9 572 U1 0 U2 8 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 AUG 6 PY 1999 VL 285 IS 5429 BP 862 EP 864 DI 10.1126/science.285.5429.862 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 223UX UT WOS:000081860900040 ER PT J AU Herrnstein, JR Moran, JM Greenhill, LJ Diamond, PJ Inoue, M Nakai, N Miyoshi, M Henkel, C Riess, A AF Herrnstein, JR Moran, JM Greenhill, LJ Diamond, PJ Inoue, M Nakai, N Miyoshi, M Henkel, C Riess, A TI A geometric distance to the galaxy NGC4258 from orbital motions in a nuclear gas disk SO NATURE LA English DT Article ID ACTIVE GALACTIC NUCLEI; NGC-4258 AB The accurate measurement of extragalactic distances is a central challenge of modern astronomy, being required for any realistic description of the age, geometry and fate of the Universe. The measurement of relative extragalactic distances has become fairly routine, but estimates of absolute distances are rare(1). In the vicinity of the Sun, direct geometric techniques for obtaining absolute distances, such as orbital parallax, are feasible, but such techniques have hitherto been difficult to apply to other galaxies. As a result, uncertainties in the expansion rate and age of the Universe are dominated by uncertainties in the absolute calibration of the extragalactic distance ladder(2). Here we report a geometric distance to the galaxy NGC4258, which we infer from the direct measurement of orbital motions in a disk of gas surrounding the nucleus of this galaxy. The distance so determined-7.2 +/- 0.3 Mpc-is the most precise absolute extragalactic distance yet measured, and is likely to play an important role in future distance-scale calibrations. C1 Natl Radio Astron Observ, Socorro, NM 87801 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Jodrell Bank, Merlin & VLBI Natl Facil, Macclesfield SK11 9DL, Cheshire, England. Natl Astron Observ, Nobeyama Radio Observ, Minamisa Ku, Nagano 38413, Japan. Natl Astron Observ, VERA Project Off, Mitaka, Tokyo 1818588, Japan. Max Planck Inst Radioastron, D-53121 Bonn, Germany. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. RP Herrnstein, JR (reprint author), Natl Radio Astron Observ, POB O, Socorro, NM 87801 USA. NR 19 TC 288 Z9 290 U1 1 U2 8 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD AUG 5 PY 1999 VL 400 IS 6744 BP 539 EP 541 DI 10.1038/22972 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 223RT UT WOS:000081854800047 ER PT J AU Banford, HM Bermingham, E Collette, BB McCafferty, SS AF Banford, HM Bermingham, E Collette, BB McCafferty, SS TI Phylogenetic systematics of the Scomberomorus regalis (Teleostei : Scombridae) species group: Molecules, morphology and biogeography of Spanish mackerels SO COPEIA LA English DT Article ID MITOCHONDRIAL-DNA EVOLUTION; EASTERN PACIFIC; UNITED-STATES; ATP SYNTHASE; NUCLEAR; PANAMA; AMPLIFICATION; ISTHMUS; MODEL; DIVERGENCE AB Phylogenetic and historical biogeographic hypotheses were explored and inferred for the Scomberomorus regalis species group, composed of five New World species (S, regalis, S. brasiliensis, S. maculatus, S. concolor, and S. sierra) and the eastern Atlantic S. tritor, in testing the generalization of Rosen's eastern Pacific/eastern Atlantic track hypothesis. The Indo-West Pacific S. guttatus and Atlantic S. cavalla served as outgroups. The entire ATP synthase 8 [ATPase 8; 168 base pairs (bp)] and 6 (ATPase 6; 684 bp), and NADH ubiquinone oxidoreductase subunit 2 (ND2; 1047 bp) mitochondrial genes, and an approximately 400-bp portion of the nuclear encoded Aldolase exon 5/intron 5 were sequenced. The monophyly of the S. regalis species group was fully supported, with the eastern Atlantic S. tritor basal to the New World taxa as predicted from the eastern Atlantic/eastern Pacific generalized biogeographic track. surprisingly, no differences were observed between the mitochondrial genomes of S, regalis and S. maculatus. However nuclear DNA and morphological characters confirm the species status of these two taxa; leading us to posit the introgressive loss of the S, maculatus mtDNA genome following hybridization with S. regalis. chronological estimates were applied to the phylogenetic topology combining geologic dates for putative vicariant events with molecular distance values. These estimates indicate a pre-isthmian divergence for the western Atlantic S. maculatus, followed by divergence of the common ancestors of the western Atlantic (S. brasiliensis and S. regalis) and eastern Pacific (S. concolor and S. sierra) species resulting from the rise of the Isthmus of Panama and closure of associated seaways. C1 Smithsonian Trop Res Inst, Balboa, Panama. Smithsonian Trop Res Inst, Unit 0948, APO, AA 34002 USA. Virginia Inst Marine Sci, Gloucester Point, VA 23062 USA. Natl Museum Nat Hist, Natl Systemat Lab, Natl Marine Fisheries Serv, Washington, DC 20560 USA. RP Banford, HM (reprint author), Smithsonian Trop Res Inst, Apartado 2072, Balboa, Panama. NR 68 TC 36 Z9 36 U1 0 U2 2 PU AMER SOC ICHTHYOLOGISTS HERPETOLOGISTS PI CHARLESTON PA UNIV CHARLESTON, GRICE MARINE LABORATORY, 205 FORT JOHNSON RD, CHARLESTON, SC 29412 USA SN 0045-8511 J9 COPEIA JI Copeia PD AUG 2 PY 1999 IS 3 BP 596 EP 613 PG 18 WC Zoology SC Zoology GA 227HR UT WOS:000082075500005 ER PT J AU McShea, WJ Leimgruber, P Aung, M Monfort, SL Wemmer, C AF McShea, William J. Leimgruber, Peter Aung, Myint Monfort, Steven L. Wemmer, Christen TI Range collapse of a tropical cervid (Cervus eldi) and the extent of remaining habitat in central Myanmar SO ANIMAL CONSERVATION LA English DT Article AB The thamin (Cervus eldi) is an endangered species of deer whose present range is greatly reduced from its original distribution covering the deciduous forests throughout south-east Asia. We mapped the present distribution of thamin using ground surveys and tied this information to habitat types derived from satellite images in order to detect patterns that might indicate the landscape features which precipitated the decline. We conducted a survey of 24 out of 28 Myanmar townships that were reported to contain thamin in 1992, and evidence of thamin were found in 23 of these townships, predominately in mixed deciduous forests where dipterocarp trees were present. There was no significant correlation between the number of thamin detected and forest remaining in the township, or the size of the human or livestock population. A landcover classification of Landsat Thematic Mapper images indicated 58% of the study area contained deciduous forest, of which 12% was dipterocarp forest. Forest tracts containing thamin were digitized and landscape analyses were conducted on a resampled habitat map that emphasized dry and dipterocarp deciduous forest. Of six landscape variables measured only core area size was a significant predictor for the presence of thamin. None of the unsurveyed indaing forest tracts possessed a core area large enough to support thamin. The pattern of thamin decline matches predictions that peripheral, rather than central, populations are more likely to persist in declining species. C1 [McShea, William J.; Leimgruber, Peter; Monfort, Steven L.; Wemmer, Christen] Natl Zool Pk, Conservat & Res Ctr, Front Royal, VA 22630 USA. [Aung, Myint] Dept Wildlife, Insein, Yangon, Myanmar. RP McShea, WJ (reprint author), Natl Zool Pk, Conservat & Res Ctr, 1500 Remount Rd, Front Royal, VA 22630 USA. EM wmcshea@crc.si.edu RI Leimgruber, Peter/O-1304-2015 OI Leimgruber, Peter/0000-0002-3682-0153 FU Smithsonian Institution; National Zoo; Wildlife Conservation Society; National Geographic Society; U U Ga; U Than Nwai; Thamin Ecology Team FX This work was supported by restricted endowment funds from the Smithsonian Institution, and by funds from Friends of the National Zoo, the Wildlife Conservation Society and the National Geographic Society. The field work was supported by U U Ga and U Than Nwai in the Myanmar Wildlife Department and by the hard efforts of the Thamin Ecology Team. The GIS work was assisted by Tom Small and Jeff Diez. NR 40 TC 26 Z9 27 U1 2 U2 7 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 1367-9430 J9 ANIM CONSERV JI Anim. Conserv. PD AUG PY 1999 VL 2 IS 3 BP 173 EP 183 DI 10.1111/j.1469-1795.1999.tb00063.x PG 11 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA V71EI UT WOS:000204810800003 ER PT J AU Blair, WP Sankrit, R Raymond, JC Long, KS AF Blair, WP Sankrit, R Raymond, JC Long, KS TI Distance to the Cygnus Loop from Hubble Space Telescope imaging of the primary shock front SO ASTRONOMICAL JOURNAL LA English DT Article DE ISM : individual (Cygnus Loop); shock waves; supernova remnants ID OPTICAL-EMISSION; SUPER-NOVA; REMNANTS; WAVE AB We present a Hubble Space Telescope (HST) Wide Field Planetary Camera 2 narrowband Ha image of a region on the northeastern limb of the Cygnus Loop supernova remnant. This location provides a detailed example of where the primary blast wave first encounters the surrounding interstellar medium. The filament structure is seen in exquisite detail in this image, which was obtained primarily as an EARLY ACQuisition image for a follow-up spectroscopic program. We compare the HST image with a digitized version of the POSS-I red plate to measure the proper motion of this filament. By combining this value for the proper motion with previous measurements of the shock velocity at this position we find that the distance to the Cygnus Loop is 440(-100)(+130) pc, considerably smaller than the canonical value of 770 pc. We briefly discuss the ramifications of this new distance estimate for our understanding of this prototypical supernova remnant. C1 Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. RP Blair, WP (reprint author), Johns Hopkins Univ, Dept Phys & Astron, 3400 N Charles St, Baltimore, MD 21218 USA. NR 17 TC 64 Z9 64 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 AUG PY 1999 VL 118 IS 2 BP 942 EP 947 DI 10.1086/300994 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 232JZ UT WOS:000082368700031 ER EF