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2010

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Articles 6481 - 6510 of 6945

Full-Text Articles in Physical Sciences and Mathematics

Evidence For Recent Population Bottlenecks In Northern Spotted Owls (Strix Occidentalis Caurina), W. Chris Funk, Eric D. Forsman, Matthew Johnson, Thomas D. Mullins, Susan M. Haig Jan 2010

Evidence For Recent Population Bottlenecks In Northern Spotted Owls (Strix Occidentalis Caurina), W. Chris Funk, Eric D. Forsman, Matthew Johnson, Thomas D. Mullins, Susan M. Haig

United States Geological Survey: Staff Publications

The northern spotted owl (Strix occidentalis caurina) is one of the most controversial threatened subspecies ever listed under the US Endangered Species Act. Despite protection of its remaining forest habitat, recent field studies show continued declines of northern spotted owls. One potential threat to northern spotted owls which has not yet been shown is loss of genetic variation from population bottlenecks. Bottlenecks can increase the probability of mating among related individuals, potentially causing inbreeding depression, and can decrease adaptive potential. Here we report evidence for recent bottlenecks in northern spotted owls using a large genetic dataset (352 individuals …

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Tree-Ring Dates And Demographic Change In The Southern Colorado Plateau And Rio Grande Regions, Michael S. Berry, Larry Benson Jan 2010

Tree-Ring Dates And Demographic Change In The Southern Colorado Plateau And Rio Grande Regions, Michael S. Berry, Larry Benson

United States Geological Survey: Staff Publications

In this chapter, tree-ring dates from the southern Colorado Plateau, Mogollon Highlands, and Rio Grande areas (fig. 3-1) (hereafter referred to as the study area) are used to estimate regional-scale timber-harvesting and construction activities between AD 600 and 1600 (the Basketmaker III through Pueblo IV periods). Within that time span, we focus our attention particularly on the AD 1045-1300 period, a time when anomalously wet periods alternated with megadroughts (fig. 3.2). Treering- date distributions (histograms) for eight archaeological subregions within the study area have been created using a database of more than twenty-four thousand tree-ring dates from archaeological sites. These …

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Barcoding Bushmeat: Molecular Identification Of Central African And South American Harvested Vertebrates, Mitchell J. Eaton, Greta L. Meyers, Sergios-Orestis Kolokotronis, Matthew S. Leslie, Andrew P. Martin, George Amato Jan 2010

Barcoding Bushmeat: Molecular Identification Of Central African And South American Harvested Vertebrates, Mitchell J. Eaton, Greta L. Meyers, Sergios-Orestis Kolokotronis, Matthew S. Leslie, Andrew P. Martin, George Amato

United States Geological Survey: Staff Publications

The creation and use of a globally available database of DNA sequences from a standardized gene region has been proposed as a tool for species identification, assessing genetic diversity and monitoring the legal and illegal trade in wildlife species. Here, we contribute to the Barcode of Life Data System and test whether a short region of the mitochondrial cytochrome c oxidase subunit 1 (COX1) gene would reliably distinguish among a suite of commonly hunted African and South American mammal and reptile species. We used universal primers to generate reference barcode sequences of 645 bp for 23 species from five vertebrate …

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Mineralogical And Chemical Characteristics Of Some Natural Jarosites, George A. Desborough, Kathleen S. Smith, Heather A. Lowers, Gregg A. Swayze, Jane M. Hammarstrom, Sharon F. Diehl, Reinhard W. Leinz, Rhonda L. Driscoll Jan 2010

Mineralogical And Chemical Characteristics Of Some Natural Jarosites, George A. Desborough, Kathleen S. Smith, Heather A. Lowers, Gregg A. Swayze, Jane M. Hammarstrom, Sharon F. Diehl, Reinhard W. Leinz, Rhonda L. Driscoll

United States Geological Survey: Staff Publications

This paper presents a detailed study of the mineralogical, microscopic, thermal, and spectral characteristics of jarosite and natrojarosite minerals. Systematic mineralogic and chemical examination of a suite of 32 natural stoichiometric jarosite and natrojarosite samples from diverse supergene and hydrothermal environments indicates that there is only limited solid solution between Na and K at low temperatures, which suggests the presence of a solvus in the jarosite-natrojarosite system at temperatures below about 140 °C. The samples examined in this study consist of either end members or coexisting end-member pairs of jarosite and natrojarosite. Quantitative electron-probe microanalysis data for several natural hydrothermal …

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The Influence Of Topology On Hydraulic Conductivity In A Sand-And-Gravel Aquifer, Roger H. Morin, Denis R. Leblanc, Brent M. Troutman Jan 2010

The Influence Of Topology On Hydraulic Conductivity In A Sand-And-Gravel Aquifer, Roger H. Morin, Denis R. Leblanc, Brent M. Troutman

United States Geological Survey: Staff Publications

A field experiment consisting of geophysical logging and tracer testing was conducted in a single well that penetrated a sand-and-gravel aquifer at the U.S. Geological Survey Toxic Substances Hydrology research site on Cape Cod, Massachusetts. Geophysical logs and flowmeter/pumping measurements were obtained to estimate vertical profiles of porosity ϕ, hydraulic conductivity K, temperature, and bulk electrical conductivity under background, freshwater conditions. Saline-tracer fluid was then injected into the well for 2 h and its radial migration into the surrounding deposits was monitored by recording an electromagnetic-induction log every 10 min. The field data are analyzed and interpreted primarily …

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Heat Flow And Hydrologic Characteristics At The And-1b Borehole, Andrill Mcmurdo Ice Shelf Project, Antarctica, Roger H. Morin, Trevor Williams, Stuart A. Henrys, Diana Magens, Frank Niessen, Dhiresh Hansaraj Jan 2010

Heat Flow And Hydrologic Characteristics At The And-1b Borehole, Andrill Mcmurdo Ice Shelf Project, Antarctica, Roger H. Morin, Trevor Williams, Stuart A. Henrys, Diana Magens, Frank Niessen, Dhiresh Hansaraj

United States Geological Survey: Staff Publications

The Antarctic Drilling Program (ANDRILL) successfully drilled and cored a borehole, AND-1B, beneath the McMurdo Ice Shelf and into a flexural moat basin that surrounds Ross Island. Total drilling depth reached 1285 m below sea floor (mbsf) with 98 percent core recovery for the detailed study of glacier dynamics. With the goal of obtaining complementary information regarding heat fl ow and permeability, which is vital to understanding the nature of marine hydrogeologic systems, a succession of three temperature logs was recorded over a five day span to monitor the gradual thermal recovery toward equilibrium conditions. These data were extrapolated to …

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Scale‐Invariant Stress Orientations And Seismicity Rates Near The San Andreas Fault, Amy Day-Lewis, Mark D. Zoback, Stephen Hickman Jan 2010

Scale‐Invariant Stress Orientations And Seismicity Rates Near The San Andreas Fault, Amy Day-Lewis, Mark D. Zoback, Stephen Hickman

United States Geological Survey: Staff Publications

We analyzed measurements of the direction of maximum horizontal compressive stress as a function of depth in two scientific research wells near the San Andreas Fault in central and southern California. We found that the stress orientations exhibit scale‐invariant fluctuations over intervals from tens of cm to several km. Similarity between the scaling of the stress orientation fluctuations and the scaling of earthquake frequency with fault size suggests that these fluctuations are controlled by stress perturbations caused by slip on faults of various sizes in the critically‐stressed crust adjacent to the fault. The apparent difference in stress scaling parameters between …

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The Ties That Bind: Soil Surveyor William Edgar Tharp And Oceanographic Cartographer Marie Tharp, Edward R. Landa Jan 2010

The Ties That Bind: Soil Surveyor William Edgar Tharp And Oceanographic Cartographer Marie Tharp, Edward R. Landa

United States Geological Survey: Staff Publications

The link between soil science and geology is personified in the American father and daughter: soil surveyor William Edgar Tharp (1870–1959) and oceanographic cartographer Marie Tharp (1920–2006). From 1904 to 1935, W.E. Tharp mapped soils in 14 states for the US Department of Agriculture, and campaigned during the late 1920s–early 1930s to raise awareness of the high rates of soil erosion from croplands. The lifestyle of the federal soil surveyor in the United States during the early 20th century involved frequent household moves, and it played a formative role in Marie Tharp’s childhood. Her path to a career in geology …

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Microbial Production Of Isotopically Light Iron(Ii) In A Modern Chemically Precipitated Sediment And Implications For Isotopic Variations In Ancient Rocks, G. E. Tangalos, B. L. Beard, C. M. Johnson, Charles N. Alpers, E. S. Shelobolina, H. Xu, H. Konishi, E. E. Roden Jan 2010

Microbial Production Of Isotopically Light Iron(Ii) In A Modern Chemically Precipitated Sediment And Implications For Isotopic Variations In Ancient Rocks, G. E. Tangalos, B. L. Beard, C. M. Johnson, Charles N. Alpers, E. S. Shelobolina, H. Xu, H. Konishi, E. E. Roden

United States Geological Survey: Staff Publications

The inventories and Fe isotope composition of aqueous Fe(II) and solid-phase Fe compounds were quantified in neutral-pH, chemically precipitated sediments downstream of the Iron Mountain acid mine drainage site in northern California, USA. The sediments contain high concentrations of amorphous Fe(III) oxyhydroxides [Fe(III)am] that allow dissimilatory iron reduction (DIR) to predominate over Fe–S interactions in Fe redox transformation, as indicated by the very low abundance of Cr(II)-extractable reduced inorganic sulfur compared with dilute HCl-extractable Fe. δ56Fe values for bulk HCl- and HF-extractable Fe were ≈ 0. These near-zero bulk δ56Fe values, together with the …

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Picosecond Electron Diffraction From Molecules Aligned By Dissociation, Martin Centurion, Peter Reckenthaeler, Ferenc Krausz, Ernst E. Fill Jan 2010

Picosecond Electron Diffraction From Molecules Aligned By Dissociation, Martin Centurion, Peter Reckenthaeler, Ferenc Krausz, Ernst E. Fill

Martin Centurion Publications

In gas electron diffraction an averaging over statistical directions of the molecules takes place. This results in diffraction patterns in the form of isotropic rings which yield information only on the radial distribution function displaying the inter-atomic distances. We demonstrate that by dissociating molecules with linearly polarized light the pattern becomes anisotropic. In the experiments the iodide C2F4I2 is dissociated and molecular difference intensities and difference radial distribution curves are measured for directions parallel and perpendicular to the direction of polarization. With picosecond temporal resolution the curves clearly demonstrate transient anisotropy and its decay by …

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Robust Isothermal Electric Control Of Exchange Bias At Room Temperature, Xi He, Ning Wu, Anthony N. Caruso, Elio Vescovo, Kirill D. Belashchenko, Peter A. Dowben, Christian Binek Jan 2010

Robust Isothermal Electric Control Of Exchange Bias At Room Temperature, Xi He, Ning Wu, Anthony N. Caruso, Elio Vescovo, Kirill D. Belashchenko, Peter A. Dowben, Christian Binek

Kirill Belashchenko Publications

Voltage-controlled spin electronics is crucial for continued progress in information technology. It aims at reduced power consumption, increased integration density and enhanced functionality where non-volatile memory is combined with highspeed logical processing. Promising spintronic device concepts use the electric control of interface and surface magnetization. From the combination of magnetometry, spin-polarized photoemission spectroscopy, symmetry arguments and first-principles calculations, we show that the (0001) surface of magnetoelectric Cr2O3 has a roughness-insensitive, electrically switchable magnetization. Using a ferromagnetic Pd/Co multilayer deposited on the (0001) surface of a Cr2O3 single crystal, we achieve reversible, room-temperature isothermal switching …

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Polarized Neutron Reflectometry Study Of The Magnetization Reversal Process In Yba2cu3o7 /La2/3ca1/3mno3 Superlattices Grown On Srtio3 Substrates, J. Hoppler, H. Fritzsche, V. K. Malik, J. Stahn, G. P. Cristiani, H.-U. Habermeier, M. Rössle, Jan Honolka, Axel Enders, C. Bernhard Jan 2010

Polarized Neutron Reflectometry Study Of The Magnetization Reversal Process In Yba2cu3o7 /La2/3ca1/3mno3 Superlattices Grown On Srtio3 Substrates, J. Hoppler, H. Fritzsche, V. K. Malik, J. Stahn, G. P. Cristiani, H.-U. Habermeier, M. Rössle, Jan Honolka, Axel Enders, C. Bernhard

Axel Enders Publications

Using polarized neutron reflectometry we investigated the reversal of the magnetization of a high-Tc superconductor/ferromagnet superlattice that consists of eight bilayers of YBa2Cu3O7(25.6 nm) /La2/3Ca1/3MnO3(25.6 nm) grown on a SrTiO3 substrate. The measurements were performed during a magnetization hysteresis loop at 5 K. We obtained evidence that the reversal in the vicinity of the coercive field proceeds via the switching of micrometer-sized magnetic domains that are considerably larger than the typical domains of La2/3Ca1/3MnO3. Furthermore, these large magnetic domains …

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Dissociative Electron Attachment In Nonplanar Chlorocarbons With Π*/Σ*-Coupled Molecular Orbitals, Kayvan Aflatooni, Gordon A. Gallup, Paul Burrow Jan 2010

Dissociative Electron Attachment In Nonplanar Chlorocarbons With Π*/Σ*-Coupled Molecular Orbitals, Kayvan Aflatooni, Gordon A. Gallup, Paul Burrow

Paul Burrow Publications

Total absolute cross sections for the dissociative electron attachment (DEA) process are reported for a series of nonplanar ethylenic and phenylic compounds monosubstituted with (CH2)nCl groups, where n=1–4. Coupling between the local π* molecular orbitals provided by the unsaturated moieties and the σ* (C-Cl) orbital is thus examined as a function of the separation of these groups. In particular, the coupling is viewed from the perspective of the interacting temporary negative ions formed by short lived occupation of these orbitals and their decay into the DEA channel. A theoretical treatment of “remote” bond breaking, …

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Piezoelectric Tuning Of Exchange Bias In A Batio3/Co/Coo Heterostructure, Srinivas Polisetty, W. Echtenkamp, Keith Jones, X. He, Sarbeswar Sahoo, Christian Binek Jan 2010

Piezoelectric Tuning Of Exchange Bias In A Batio3/Co/Coo Heterostructure, Srinivas Polisetty, W. Echtenkamp, Keith Jones, X. He, Sarbeswar Sahoo, Christian Binek

Christian Binek Publications

Piezoelectrically controlled strain is used for electric tuning of exchange-bias fields. A generic exchange-bias Co/CoO bilayer is deposited on the surface of a ferroelectric and thus piezoelectric BaTiO3 substrate which allows to apply electrically and thermally tunable stress in the adjacent ferromagnetic Co thin film. The stress-induced strain alters foremost the magnetic anisotropy of the Co film and by that the magnetization orientation at the Co/CoO interface modifying the exchange-bias field. This results in a pronounced electrically induced weakening of the exchange bias but also includes the possibility of tuning the exchange-bias field through a subtle sign change from …

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Vibrational Properties Of Ferroelectric Β-Vinylidene Fluoride Polymers And Oligomers, Serge M. Nakhmanson, Rafal Korlacki, J. Travis Johnston, Stephen Ducharme, Zhongxin Ge, James M. Takacs Jan 2010

Vibrational Properties Of Ferroelectric Β-Vinylidene Fluoride Polymers And Oligomers, Serge M. Nakhmanson, Rafal Korlacki, J. Travis Johnston, Stephen Ducharme, Zhongxin Ge, James M. Takacs

Stephen Ducharme Publications

We utilize a plane-wave density-functional theory approach to investigate the vibrational properties of the all-trans ferroelectric phase of poly(vinylidene fluoride) (β-PVDF) showing that its stable state corresponds to the Ama2 structure with ordered dihedral tilting of the VDF monomers along the polymer chains. We then combine our theoretical analysis with IR spectroscopy to examine vibrations in oligomer crystals that are structurally related to the β-PVDF phase. We demonstrate that these materials—which can be grown in a highly crystalline form—exhibit IR activity similar to that of β-PVDF, making them an attractive choice for the studies of electroactive phenomena and phase transitions …

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Why Ferroelectric Polyvinylidene Fluoride Is Special, Matt Poulsen, Stephen Ducharme Jan 2010

Why Ferroelectric Polyvinylidene Fluoride Is Special, Matt Poulsen, Stephen Ducharme

Stephen Ducharme Publications

Ferroelectric polymers entail a number of constraints, which together limit the useful compositional variations. These constraints include the following: a stable molecular dipole moment, compact crystal structure, conformational flexibility, and minimal steric hindrance. They are well satisfied by the prototype ferroelectric polymer, polyvinylidene fluoride, and yet almost every other conceivable molecular structure is limited by comparison.

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Probing Equilibrium By Nonequilibrium Dynamics: Aging In Co/Cr Superlattices, Tathagata Mukherjee, M. Pleimling, Christian Binek Jan 2010

Probing Equilibrium By Nonequilibrium Dynamics: Aging In Co/Cr Superlattices, Tathagata Mukherjee, M. Pleimling, Christian Binek

Christian Binek Publications

Magnetization relaxation is investigated in a structurally ordered magnetic Co/Cr superlattice. Tailored nanoscale periodicity creates mesoscopic spatial magnetic correlations with slow relaxation dynamics when quenching the system into a nonequilibrium state. Magnetization transients are measured after exposing the heterostructure to a magnetic set field for various waiting times. Scaling analysis reveals an asymptotic powerlaw behavior in accordance with a full aging scenario. The temperature dependence of the relaxation exponent shows pronounced anomalies at the equilibrium phase transitions of the antiferromagnetic superstructure and the ferromagnetic to paramagnetic transition of the Co layers. The latter leaves only weak fingerprints in the equilibrium …

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Ab Initio Calculations And Ellipsometry Measurements Of The Optical Properties Of The Layered Semiconductor In4Se3, L. Makinistian, E. A. Albanesi, N. V. Gonzalez Lemus, A. G. Petukhov, D. Schmidt, Eva Schubert, M. Schubert, Yaroslav B. Losovyj, P. Galiy, Peter A. Dowben Jan 2010

Ab Initio Calculations And Ellipsometry Measurements Of The Optical Properties Of The Layered Semiconductor In4Se3, L. Makinistian, E. A. Albanesi, N. V. Gonzalez Lemus, A. G. Petukhov, D. Schmidt, Eva Schubert, M. Schubert, Yaroslav B. Losovyj, P. Galiy, Peter A. Dowben

Peter Dowben Publications

In this work, we present a thorough study of the optical properties of the layered orthorhombic compound In4Se3. The dielectric function—real and imaginary parts, the complex refraction index, the reflectivity, the absorption coefficient, and the conductivity of In4Se3 were calculated with the inclusion of the spin-orbit interaction, using an ab initio FP-LAPW method based on DFT. Also, generalized ellipsometry was employed for more precise measurement of the anisotropic dielectric functions for polarization along crystal a, b, and c axes of orthorhombic absorbing In4Se3 single crystals cut approximately parallel to …

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The Local Structure Of Transition Metal Doped Semiconducting Boron Carbides, Jing Liu, Guangfu Luo, Wai-Ning Mei, Orhan Kizilkaya, Eric D. Shepherd, Jennifer I. Brand, Peter A. Dowben Jan 2010

The Local Structure Of Transition Metal Doped Semiconducting Boron Carbides, Jing Liu, Guangfu Luo, Wai-Ning Mei, Orhan Kizilkaya, Eric D. Shepherd, Jennifer I. Brand, Peter A. Dowben

Peter Dowben Publications

Transition metal doped boron carbides produced by plasma enhanced chemical vapour deposition of orthocarborane (closo-1,2-C2B10H12) and 3d metal metallocenes were investigated by performing K-edge extended x-ray absorption fine structure and x-ray absorption near edge structure measurements. The 3d transition metal atom occupies one of the icosahedral boron or carbon atomic sites within the icosahedral cage. Good agreement was obtained between experiment and models for Mn, Fe and Co doping, based on the model structures of two adjoined vertex sharing carborane cages, each containing a transition metal. The local spin configurations of all …

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Double Parton Interactions In Γ = 3 Jet Events In Pp Collisions At √S = 1.96 Tev, V. M. Abazov, Kenneth A. Bloom, Gregory Snow, D0 Collaboration Jan 2010

Double Parton Interactions In Γ = 3 Jet Events In Pp Collisions At √S = 1.96 Tev, V. M. Abazov, Kenneth A. Bloom, Gregory Snow, D0 Collaboration

Kenneth Bloom Publications

We have used a sample of γ + 3 jets events collected by the D0 experiment with an integrated luminosity of about 1 fb-1 to determine the fraction of events with double parton scattering (fDP) in a single pp collision at √s = 1.96 TeV. The DP fraction and effective cross section (τeff ), a process-independent scale parameter related to the parton density inside the nucleon, are measured in three intervals of the second (ordered in pT) jet transverse momentum pjet2T within the range 15 ≤ pjet2T ≤ …

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Search For Higgs Boson Production In Dilepton And Missing Energy Final States With 5.4 Fb-1 Of Pp Collisions At √S = 1.96 Tev, V. M. Abazov, Kenneth A. Bloom, Gregory Snow, D0 Collaboration Jan 2010

Search For Higgs Boson Production In Dilepton And Missing Energy Final States With 5.4 Fb-1 Of Pp Collisions At √S = 1.96 Tev, V. M. Abazov, Kenneth A. Bloom, Gregory Snow, D0 Collaboration

Kenneth Bloom Publications

A search for the standard model Higgs boson is presented using events with two charged leptons and large missing transverse energy selected from 5.4 fb-1 of integrated luminosity in pp collisions at √s = 1.96 TeV collected with the D0 detector at the Fermilab Tevatron collider. No significant excess of events above background predictions is found, and observed (expected) upper limits at 95% confidence level on the rate of Higgs boson production are derived that are a factor of 1.55 (1.36) above the predicted standard model cross section at mH = 165 GeV.

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Combination Of Tevatron Searches For The Standard Model Higgs Boson In The W+W- Decay Mode, V. M. Abazov, Kenneth A. Bloom, Gregory Snow, D0 Collaboration Jan 2010

Combination Of Tevatron Searches For The Standard Model Higgs Boson In The W+W- Decay Mode, V. M. Abazov, Kenneth A. Bloom, Gregory Snow, D0 Collaboration

Kenneth Bloom Publications

We combine searches by the CDF and D0 Collaborations for a Higgs boson decaying to W+W-. The data correspond to an integrated total luminosity of 4.8 (CDF) and 5.4 (D0) fb-1 of pp collisions at √s = 1.96 TeV at the Fermilab Tevatron collider. No excess is observed above background expectation, and resulting limits on Higgs boson production exclude a standard model Higgs boson in the mass range 162–166 GeV at the 95% C.L.

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Resource Selection By Elk In An Agro-Forested Landscape Of Northwestern Nebraska, David M. Baasch, Justin W. Fischer, Scott E. Hygnstrom, Kurt C. Vercauteren, Andrew J. Tyre, Joshua J. Millspaugh, James W. Merchant, Jerry D. Volesky Jan 2010

Resource Selection By Elk In An Agro-Forested Landscape Of Northwestern Nebraska, David M. Baasch, Justin W. Fischer, Scott E. Hygnstrom, Kurt C. Vercauteren, Andrew J. Tyre, Joshua J. Millspaugh, James W. Merchant, Jerry D. Volesky

School of Natural Resources: Faculty Publications

In recent years, elk have begun recolonizing areas east of the Rocky Mountains that are largely agroforested ecosystems composed of privately owned land where management of elk is an increasing concern due to crop and forage depredation and interspecific disease transmission. We used a Geographic Information System, elk use locations (n = 5013), random locations (n = 25,065), discrete-choice models, and information-theoretic methods to test hypotheses about elk resource selection in an agro-forested landscape located in the Pine Ridge region of northwestern Nebraska, USA. Our objectives were to determine landscape characteristics selected by female elk and identify publicly owned land …

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Seroprevalence Of Equine Influenza Virus In Northeast And Southern Mexico, B. J. Blitvich, L. A. Ibarra-Juarez, A. J. Cortes-Guzman, J. J. Root, A. B. Franklin, H. J. Sullivan, I. Fernandez-Salas Jan 2010

Seroprevalence Of Equine Influenza Virus In Northeast And Southern Mexico, B. J. Blitvich, L. A. Ibarra-Juarez, A. J. Cortes-Guzman, J. J. Root, A. B. Franklin, H. J. Sullivan, I. Fernandez-Salas

United States Department of Agriculture Wildlife Services: Staff Publications

EQUINE influenza A virus (EIV) is a highly infectious respiratory pathogen of horses (Hannant and Mumford 1996, Palese and Shaw 2007). The illness is characterized by an abrupt onset of fever, depression, coughing and nasal discharge, and is often complicated by secondary bacterial infections that can lead to pneumonia and death. Two subtypes of EIV, H3N8 and H7N7, have been isolated. The H7N7 subtype was first isolated from a horse in Czechoslovakia in 1956 (Prague/56), and the H3N8 subtype was first isolated from a horse in Miami in 1963 (Sovinova and others 1958, Waddell and others 1963). The last confirmed …

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Temporal Variation In Terrestrial Invertebrate Consumption By Laughing Gulls In New York, Glen E. Bernhardt, Lisa Kutschbach-Brohl, Brian E. Washburn, Richard Chipman, Laura Francoeur Jan 2010

Temporal Variation In Terrestrial Invertebrate Consumption By Laughing Gulls In New York, Glen E. Bernhardt, Lisa Kutschbach-Brohl, Brian E. Washburn, Richard Chipman, Laura Francoeur

United States Department of Agriculture Wildlife Services: Staff Publications

Laughing gulls (Larus atricilla) are commonly found in many areas of North America and little is known about their diet, particularly in coastal-urban interfaces where gull-aircraft collisions can be a serious concern. The objective of this study was to describe and quantify the consumption of terrestrial invertebrates by laughing gulls at a coastal-urban interface in the northeastern United States. We examined the stomach contents of laughing gulls (n = 1053) collected during wildlife damage management operations at John F. Kennedy International Airport during the summers of 2003 and 2004. Terrestrial invertebrates consumed by laughing gulls represented 2 taxonomic …

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Using A Cost-Effectiveness Model To Determine The Applicability Of Ovocontrol G To Manage Nuisance Canada Geese, Joe Caudell, Stephanie A. Shwiff, Michael Slater Jan 2010

Using A Cost-Effectiveness Model To Determine The Applicability Of Ovocontrol G To Manage Nuisance Canada Geese, Joe Caudell, Stephanie A. Shwiff, Michael Slater

United States Department of Agriculture Wildlife Services: Staff Publications

OvoControl G is a relatively new product that reduces hatchability of Canada goose (Branta canadensis) eggs, and few data are available on its cost effectiveness. Variables such as presence of nontargets, alternative foods, and public support can affect cost efficacy. We present a model that uses these and other factors to estimate the cost of application of OvoControl G for managing nuisance Canada geese. We found that at low goose densities (<35 pairs of geese), fixed labor was a significant portion of costs. As goose densities increase, OvoControl G becomes more cost effective than other methods, such as egg oiling or addling. Managers can use this model to determine whether OvoControl G will provide a successful and cost-effective treatment for population control of Canada geese in specific management areas.

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Reproductive Biology Of Male Brown Treesnakes (Boiga Irregularis) On Guam, Tom Mathies, John A. Cruz, Valentine A. Lance, Julie A. Savidge Jan 2010

Reproductive Biology Of Male Brown Treesnakes (Boiga Irregularis) On Guam, Tom Mathies, John A. Cruz, Valentine A. Lance, Julie A. Savidge

United States Department of Agriculture Wildlife Services: Staff Publications

Reproductive biology of males in the Guam population of the Brown Treesnake, Boiga irregularis, was investigated through monthly examinations of the urogenital system organs and plasma testosterone levels. All males examined during the 12 consecutive months of the study were spermatogenic and had sperm in the ductus epididymis and ductus deferens. No evidence of testicular recrudescence or regression was observed. Testis mass did not vary among months. Epithelial height of the kidney sexual segment was the only feature examined that varied significantly among months, with lowest heights observed in May through July. Despite this variation, the sexual segment in all …

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Contraceptive Efficacy Of A Novel Intrauterine Device (Iud) In White-Tailed Deer, Karl D. Malcolm, Timothy R. Van Deelen, David Drake, Darrel J. Kesler, Kurt C. Vercauteren Jan 2010

Contraceptive Efficacy Of A Novel Intrauterine Device (Iud) In White-Tailed Deer, Karl D. Malcolm, Timothy R. Van Deelen, David Drake, Darrel J. Kesler, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Overabundant white-tailed deer (Odocoileus virginianus) pose risks to property, health, and safety of human beings. Public concerns about lethal management can impair efforts to address these issues, particularly in urban settings. Several techniques developed for reducing reproductive output of deer have limited utility because they require repeated dosing to achieve permanent effect and face uncertain regulatory approval for use beyond experimentation. From 10 August 2006 through 30 December 2007, we evaluated the contraceptive efficacy of copper-containing intrauterine devices (IUDs) implanted trans-cervically in white-tailed deer at the E.S. George Reserve in Pinckney, Michigan. Intrauterine devices were implanted before (n …

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Acetaminophen As An Oral Toxicant For Nile Monitor Lizards (Varanus Niloticus) And Burmese Pythons (Python Molurus Bivittatus), Richard E. Mauldin, Peter J. Savarie Jan 2010

Acetaminophen As An Oral Toxicant For Nile Monitor Lizards (Varanus Niloticus) And Burmese Pythons (Python Molurus Bivittatus), Richard E. Mauldin, Peter J. Savarie

United States Department of Agriculture Wildlife Services: Staff Publications

Context. Invasive species are a growing global problem. Biological invasions can result in numerous harmful impacts on local ecologies, and non-native herpetofauna are frequently ignored. Nile monitor lizards (Varanus niloticus) and Burmese pythons (Python molurus bivittatus, recently reassessed as Python bivittatus bivittatus), have become established in southern Florida. Both are large, semi-aquatic predators that pose serious threats to a variety of threatened and endangered species, as well as to the unique ecology of the area.

Aims. Acetaminophen (CAS#103-90-2), a lethal oral toxicant for the invasive brown treesnake (Boiga irregularis) on Guam, was investigated …

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Seeking A Second Opinion: Uncertainty In Disease Ecology, Brett T. Mcclintock, James D. Nichols, Larissa L. Bailey, Darryl I. Mackenzie, William. L. Kendall, Alan B. Franklin Jan 2010

Seeking A Second Opinion: Uncertainty In Disease Ecology, Brett T. Mcclintock, James D. Nichols, Larissa L. Bailey, Darryl I. Mackenzie, William. L. Kendall, Alan B. Franklin

United States Department of Agriculture Wildlife Services: Staff Publications

Analytical methods accounting for imperfect detection are often used to facilitate reliable inference in population and community ecology. We contend that similar approaches are needed in disease ecology because these complicated systems are inherently difficult to observe without error. For example, wildlife disease studies often designate individuals, populations, or spatial units to states (e.g., susceptible, infected, post-infected), but the uncertainty associated with these state assignments remains largely ignored or unaccounted for. We demonstrate how recent developments incorporating observation error through repeated sampling extend quite naturally to hierarchical spatial models of disease effects, prevalence, and dynamics in natural systems. A highly …

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