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Impact Of Age And Sex Of Rocky Mountain Elk (Cervus Elaphus Nelson) On Follicle Counts From Rectal Mucosal Biopsies For Preclinical Detection Of Chronic Wasting Disease, Terry R. Spraker, Kurt C. Vercauteren, Tom L. Gidlewski, Randy D. Munger, W. David Walter, Aru Balachandran Walter

United States Department of Agriculture Wildlife Services: Staff Publications

To determine if the number of rectal lymphoid follicles decreases with respect to age and sex relative to diagnosis of chronic wasting disease (CWD), rectal biopsies (n = 1,361) were taken from captive Rocky Mountain elk (Cervus elaphus nelsoni) at 4 ranches in the western United States between 2005 and 2008. Rectal tissues were stained with a monoclonal antibody (F99/97.6.1), which selectively stains the abnormal isoform of the prion protein associated with CWD of elk. The number of lymphoid follicles obtained from typical biopsy tissues decreased with the age of the animal. The acceptable number of lymphoid follicles …

Longevity Of Dayglo Fluorescent Particle Marker Used To Mark Birds In Flight Pen And Field, Shelagh K. Tupper, John L. Cummings, Richard M. Engeman

United States Department of Agriculture Wildlife Services: Staff Publications

Spray application of fluorescent particles is a widely used and very valuable technique for marking birds. This remains one of the few practical means to mark large numbers of birds for monitoring movement, despite recent availability of a variety of more technologically advanced options. We monitored the longevity of the DayGlo fluorescent particle marker on red-winged blackbirds under simulated field conditions in a flight pen, and in an observational field experiment. In the pen study we banded 52 red-winged blackbirds with individually numbered leg bands, and sprayed them with DayGlo fluorescent particle marker from a distance of ~50 cm, on …

Antemortem Detection Of PrpCwd In Preclinical, Ranch-Raised Rocky Mountain Elk (Cervus Elaphus Nelson) By Biopsy Of The Rectal Mucosa, Terry R. Spraker, Kurt C. Vercauteren, Thomas Gidlewski, David A. Schneider, Randy Munger, Aru Balachandran, Katherine I. O’Rourke

United States Department of Agriculture Wildlife Services: Staff Publications

Antemortem biopsy of the rectal mucosa was evaluated as a method for the preclinical diagnosis of chronic wasting disease (CWD) in a herd of ranch-raised Rocky Mountain elk (Cervus elaphus nelson) quarantined because of exposure to CWD. Biopsy samples were obtained from 41 elk during the winter of 2005–2006 and from 26 elk from that herd still alive and available for testing during the winter of 2006–2007. Samples were examined for PrP^CWD, the protein marker for CWD infection, by immunohistochemistry. PrP^CWD was detected in follicles of the rectoanal mucosa-associated lymphoid tissue in biopsy samples from …

Threshold Concentrations Of An Anthraquinone-Based Repellent For Canada Geese, Red-Winged Blackbirds, And Ring-Necked Pheasants, Scott J. Werner, James C. Carlson, Shelagh K. Tupper, Michele M. Santer, George M. Linz

United States Department of Agriculture Wildlife Services: Staff Publications

Wildlife repellents provide a non-lethal alternative for managing the monetary impacts of agricultural depredation. For the purpose of developing of an effective avian repellent, we established repellency thresholds of an anthraquinone-based repellent for Canada geese (Branta canadensis), red-winged blackbirds (Agelaius phoeniceus), and ring-necked pheasants (Phasianus colchicus) in captivity. We conducted a concentration–response experiment with Canada geese offered cornseeds treated with six concentrations of Avipel repellent (a.i. 50% 9,10-anthraquinone). Based upon our laboratory efficacy data, we used non-linear regression to predict a threshold concentration of 1450 ppm anthraquinone for geese offered treated corn seeds (i.e., …

Options For The Control Of Disease 3: Targeting The Environment, Alastair Ward, Kurt C. Vercauteren, W. David Walter, Emmanuellle Gilot-Fromont, Sophie Rossi, Gareth Edwards- Jones, Mark S. Lambert, Michael R. Hutchings, Richard J. Delahay

United States Department of Agriculture Wildlife Services: Staff Publications

Management of wildlife disease can be targeted at pathogens, hosts or vector populations, but may also focus on the environment. As constituent elements of any given environment, resident wildlife populations, and their pathogens, may be profoundly influenced by environmental change, in terms of their abundance, distribution and behavior. Hence, it is reasonable to expect that incorporation of environmental manipulation into a program to control wildlife diseases may potentially result in outcomes as effective as direct intervention aimed at hosts, pathogens and vectors.

Crop, Native Vegetation, And Biofuels: Response Of White- Tailed Deer To Changing Management Priorities, W. David Walter, Kurt C. Vercauteren, Jason Gilsdorf, Scott E. Hygnstrom

United States Department of Agriculture Wildlife Services: Staff Publications

The expansion of the cellulosic biofuels industry throughout the United States has broad-scale implications for wildlife management on public and private lands. Knowledge is limited on the effects of reverting agriculture to native grass, and vice versa, on size of home range and habitat use of white-tailed deer (Odocoileus virginianus). We followed 68 radio-collared female deer from 1991 through 2004 that were residents of DeSoto National Wildlife Refuge (DNWR) in eastern Nebraska, USA. The refuge was undergoing conversion of vegetation out of row-crop agriculture and into native grass, forest, and emergent aquatic vegetation. Habitat in DNWR consisted of …

Influence Of Vitamin K-Rich Plant Foods On Anticoagulant Baiting Efficacy In Wild House Mice, Wild Norway Rats, And Wild Black Rats, G. W. Witmer, P. W. Burke

United States Department of Agriculture Wildlife Services: Staff Publications

Rodents introduced to islands have caused the extinction of many species of animals. Anticoagulant rodenticides are relied on to eradicate rodents from these islands, but if the rodents are eating plant materials that contain high amounts of vitamin K (the antidote to anticoagulants) anticoagulant rodenticides may not be effective. In a laboratory trial, individually caged Noway Rats Rattus norvegicus, Black Rats R. raffus and House Mice Mus musculus were fed fresh plant material high in vitamin K (Collards [0.62 mg vitamin K per 100 g] and Brussels Sprouts [0.19 mg vitamin K per 100 g]) for a period of …

Fate Of Sulfamethoxazole, 4-Nonylphenol, And 17Β-Estradiol In Groundwater Contaminated By Wastewater Treatment Plant Effluent, Larry Barber, Steffanie Keefe, Dennis Leblanc, Paul Bradley, Francis Chapelle, Michael Meyer, Keith Lofton, Dana Kolpin, Fernando Rubio

United States Geological Survey: Staff Publications

Organic wastewater contaminants (OWCs) were measured in samples collected from monitoring wells located along a 4.5- km transect of a plume of groundwater contaminated by 60 years of continuous rapid infiltration disposal of wastewater treatment plant effluent. Fifteen percent of the 212OWCs analyzed were detected, including the antibiotic sulfamethoxazole (SX), the nonionic surfactant degradation product 4-nonylphenol (NP), the solvent tetrachloroethene (PCE), and the disinfectant 1,4-dichlorobenzene (DCB). Comparison of the 2005 sampling results to data collected from the same wells in 1985 indicates that PCE and DCB are transported more rapidly in the aquifer than NP, consistent with predictions based on …

Biodegradation Of 17Β-Estradiol, Estrone And Testosterone In Stream Sediments, Paul Bradley, Larry Barber, Francis Chapelle, James Gray, Dana Kolpin, Peter B. Mcmahon

United States Geological Survey: Staff Publications

Biodegradation of 17β-estradiol (E2), estrone (E1), and testosterone (T) was investigated in three wastewater treatment plant (WWTP) affected streams in the United States. Relative differences in the mineralization of [4-¹⁴C] substrates were assessed in oxic microcosms containing saturated sediment or water-only from locations upstream and downstream of the WWTP outfall in each system. Upstream sediment demonstrated significant mineralization of the “A” ring of E2, E1, and T, with biodegradation of T consistently greater than that of E2 and no systematic difference in E2 and E1 biodegradation. “A” ring mineralization also was observed in downstream sediment, with E1 and …

Response Of Sandhill Crane (Grus Canadensis Riverine Roosting Habitat To Changes In Stage And Sandbar Morphology, Paul Kinzel, Jonathan Nelson, Ashley Heckman

United States Geological Survey: Staff Publications

Over the past century, flow regulation and vegetation encroachment have reduced active channel widths along the central Platte River, Nebraska. During the last two decades, an annual program of in-channel vegetation management has been implemented to stabilize or expand active channel widths. Vegetation management practices are intended to enhance riverine habitats which include nocturnal roosting habitat for sandhill cranes. Evaluating the success of other management treatments such as streamflow modification requires an understanding of how flow shapes the sandbars in the river and how sandbar morphology interacts with flow to create crane habitat. These linkages were investigated along a 1-km …

Prevalence Of Antibodies To West Nile Virus And Other Arboviruses Among Crested Caracaras (Caracara Cheriway) In Florida, Nicole M. Nemeth, James F. Dwyer, Joan L. Morrison, James D. Fraser

United States Department of Agriculture Wildlife Services: Staff Publications

We documented the antibody prevalence to three arboviruses, St. Louis encephalitis virus (SLEV), eastern equine encephalitis virus (EEEV), and West Nile virus (WNV), in Crested Caracaras (Caracara cheriway; n = 80) in Florida from 2007 to 2008. Antibody prevalence to WNV was higher (9%) than for the other viruses. Most seropositive birds were adults (≥3 yr of age), with 55% of adults testing positive for antibodies to at least one virus. Adults were significantly more likely to have antibodies to WNV than nonadults (P<0.001). Prevalence of SLEV and EEEV antibodies among Crested Caracaras was 3% for each virus, and three adult caracaras had indistinguishable anti-flavivirus antibodies. The susceptibility of Crested Caracaras to adverse effects of WNV, SLEV, or EEEV infection remains unknown; however, we observed that some free-ranging individuals survived infection and successfully fledged young. Knowledge of arboviral infection among Florida’s Crested Caracara, which is both state and federally threatened, is valuable considering increasing pressure on this population from rapid and extensive habitat alterations.

Implications For The Dynamic Health Of A Glacier From Comparison Of Conventional And Reference-Surface Balances, W. D. Harrison, L. H. Cox, R. Hock, R. S. March, E. C. Pettit

United States Geological Survey: Staff Publications

Conventional and reference-surface mass-balance data from Gulkana and Wolverine Glaciers, Alaska, USA, are used to address the questions of how rapidly these glaciers are adjusting (or ‘responding’) to climate, whether their responses are stable, and whether the glaciers are likely to survive in today’s climate. Instability means that a glacier will eventually vanish, or at least become greatly reduced in volume, if the climate stabilizes at its present state. A simple non-linear theory of response is presented for the analysis. The response of Gulkana Glacier is characterized by a timescale of several decades, but its stability and therefore its survival …

Geochemical Evidence For African Dust And Volcanic Ash Inputs To Terra Rossa Soils On Carbonate Reef Terraces, Northern Jamaica, West Indies, Daniel R. Muhs, James R. Budahn

United States Geological Survey: Staff Publications

The origin of red or reddish-brown, clay-rich, ‘‘terra rossa’’ soils on limestone has been debated for decades. A traditional qualitative explanation for their formation has been the accumulation of insoluble residues as the limestone is progressively dissolved over time. However, this mode of formation often requires unrealistic or impossible amounts of carbonated is solution. Therefore, where this mechanism is not viable and where local fluvial or colluvial inputs can be ruled out, an external source or sources must be involved in soil formation.

Quantum Simulation Of High-Order Harmonic Spectra Of The Hydrogen Atom, A. D. Bandrauk, S. Chelkowski, Dennis J. Diestler, J. Manz, K.-J. Yuan

Department of Agronomy and Horticulture: Faculty Publications

Three alternative forms of harmonic spectra, based on the dipole moment, dipole velocity, and dipole acceleration, are compared by a numerical solution of the Schrödinger equation for a hydrogen atom interacting with a linearly polarized laser pulse, whose electric field is given by E(t)= E₀f(t)cos(ω₀t + η) with Gaussian carrier envelope f(t) = exp(−t² /δ²). The carrier frequency ω₀ is fixed to correspond to a wavelength of 800 nm. Spectra for a selection of pulses, for which the intensity I₀=cε₀E²₀, duration T∞ δ, …

Farmers And Nature Conservation: What Is Known About Attitudes, Context Factors And Actions Affecting Conservation?, Johan Ahnström, Jenny Höckert, Hanna L. Bergea, Charles A. Francis, Peter Skelton, Lars Hallgren

Department of Agronomy and Horticulture: Faculty Publications

Farmers’ attitudes towards viability of specific conservation practices or actions strongly impact their decisions on adoption and change. This review of ‘attitude’ information reveals a wide range of perceptions about what conservation means and what the impacts of adoption will mean in economic and environmental terms. Farmers operate in a tight financial situation, and in parts of the world they are highly dependent on government subsidies, and cannot afford to risk losing that support. Use of conservation practices is most effective when these are understood in the context of the individual farm, and decisions are rooted in land and resource …

Indirect Land Use Emissions In The Life Cycle Of Biofuels: Regulations Vs. Science, Adam J. Liska, Richard K. Perrin

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Recent legislative mandates have been enacted at state and federal levels with the purpose of reducing life cycle greenhouse gas (GHG) emissions from transportation fuels. This legislation encourages the substitution of fossil fuels with “low-carbon” fuels. The burden is put on regulatory agencies to determine the GHG-intensity of various fuels, and those agencies naturally look to science for guidance. Even though much progress has been made in determining the direct life cycle emissions from the production of biofuels, the science underpinning the estimation of potentially significant emissions from indirect land use change (ILUC) is in its infancy. As legislation requires …

Chemchains: A Platform For Simulation And Analysis Of Biochemical Networks Aimed To Laboratory Scientists, Tomáš Helikar, Jim A. Rogers

Department of Biochemistry: Faculty Publications

Background: New mathematical models of complex biological structures and computer simulation software allow modelers to simulate and analyze biochemical systems in silico and form mathematical predictions. Due to this potential predictive ability, the use of these models and software has the possibility to compliment laboratory investigations and help refine, or even develop, new hypotheses. However, the existing mathematical modeling techniques and simulation tools are often difficult to use by laboratory biologists without training in high-level mathematics, limiting their use to trained modelers.

Results: We have developed a Boolean network-based simulation and analysis software tool, ChemChains, which combines the advantages of …

Something Old, Something New, Something Borrowed; How The Thermoacidophilic Archaeon Sulfolobus Solfataricus Responds To Oxidative Stress, Walid S. Maaty, Blake Wiedenheft, Pavel Tarlykov, Nathan Schaff, Joshua Heinemann, Jim Robinson-Cox, Jacob Valenzuela, Amanda Dougherty, Paul H. Blum, C. Martin Lawrence, Trevor Douglas, Mark J. Young, Brian Bothner

School of Biological Sciences: Faculty Publications

To avoid molecular damage of biomolecules due to oxidation, all cells have evolved constitutive and responsive systems to mitigate and repair chemical modifications. Archaea have adapted to some of the most extreme environments known to support life, including highly oxidizing conditions. However, in comparison to bacteria and eukaryotes, relatively little is known about the biology and biochemistry of archaea in response to changing conditions and repair of oxidative damage. In this study transcriptome, proteome, and chemical reactivity analyses of hydrogen peroxide (H2O2) induced oxidative stress in Sulfolobus solfataricus (P2) were conducted. Microarray analysis of mRNA expression showed that 102 transcripts …

Evolution Of Duplicated Β-Globin Genes And The Structural Basis Of Hemoglobin Isoform Differentiation In Mus, Amy M. Runck, Hideaki Moriyama, Jay F. Storz

Jay F. Storz Publications

The functional diversification of multigene families may be strongly influenced by mechanisms of concerted evolution such as interparalog gene conversion. The β-globin gene family of house mice (genus Mus) represents an especially promising system for evaluating the effects of gene conversion on the functional divergence of duplicated genes. Whereas the majority of mammalian species possess tandemly duplicated copies of the adult β-globin gene that are identical in sequence, natural populations of house mice are often polymorphic for distinct two-locus haplotypes that differ in levels of functional divergence between duplicated β-globin genes, HBB-T1 and HBB-T2. Here, we use a phylogenetic …

Ultrashort Pulse Electron Gun With A Mhz Repetition Rate, D. Wytrykus, Martin Centurion, P. Reckenthaeler, F. Krausz, A. Apolonski, E. Fill

Martin Centurion Publications

We report the construction of an electron gun emitting ultrashort pulses with a repetition rate of 2.7 MHz. The gun works at an acceleration voltage of 20 kV and is operated with a laser oscillator having an ultralong cavity. A low number of electrons per pulse eliminates space charge broadening. Electron yield and beam profiles are measured for operation with laser wavelengths of 800, 400, and 266 nm. The initial energy spread of the electrons is determined for these three wavelengths, and pulse durations of 600, 390, and 270 fs are inferred from the data.

Negative-Ion Resonances In Zinc: A Study In Elastic Electron Scattering And Electron Transmission, S. A. Napier, D. Cvejanović, Paul D. Burrow, J. F. Williams, J. A. Michejda, L. Pravica

Paul Burrow Publications

The energies, widths, and angular behavior of negative-ion resonances in zinc atoms are determined using the complementary experimental techniques of electron transmission and angular differential elastic scattering.

Start The Presses, Stephen V. Ducharme, Alexei Gruverman

Stephen Ducharme Publications

A simple nanoimprinting method creates arrays of ferroelectric polymer structures suitable for low-cost, non-volatile memories. With the development of nanoimprinted high-quality ferroelectric nanomesa arrays, it seems that we now have all the necessary ingredients to print inexpensive, disposable organic memory chips.

Magnetism Of Cr-Doped Diamond-Like Carbon, J. A. Colón Santana, Ralph Skomski, V. R. Singh, V. Palshin, A. Petukhov, Yaroslav B. Losovyj, Andrei Sokolov, Peter A. Dowben, Ihor Ketsman

Peter Dowben Publications

Chromium-doped hydrogenated diamond-like carbon (Cr-DLC) and chromium carbide hydrogenated DLC alloys were synthesized by plasma-assisted vapor deposition and investigated by x-ray absorption near edge structure spectroscopy, extended x-ray absorption fine structure, and superconducting quantum interference device (SQUID) magnetometry. Structural and magnetic properties of the doped and alloy materials were investigated as a function of the Cr concentration (0.1–20 at. %). Toward the upper end of the concentration range, Cr precipitates in the form of chromium carbide (Cr₃C₂) nanoclusters. For low Cr concentrations, the systems are ferromagnetic at very low temperatures, whereas the chromium carbide clusters appear …

Radiation-Induced Decomposition Of The Metal-Organic Molecule Bis(4-Cyano-2,2,6,6-Tetramethyl-3,5-Heptanedionato)Copper(Ii), David Wisbey, Ning Wu, Yaroslav B. Losovyj, Ihor Ketsman, A. N. Caruso, Danqin Feng, John Belot, Elio Vescovo, Peter A. Dowben

Peter Dowben Publications

The effects of vacuum ultraviolet radiation on the adsorbed copper center molecule bis(4-cyano-2,2,6,6- tetramethyl-3,5-heptanedionato)copper(II) (or Cu(CNdpm)₂), (C₂₄H₃₆N₂O₄Cu, Cu(II)) was studied by photoemission spectroscopy. Changes in the ultraviolet photoemission spectra (UPS) of Cu(CNdpm)₂, adsorbed on Co(1 1 1), indicate that the ultraviolet radiation leads to decomposition of Cu(CNdpm)₂ and this decomposition is initially dominated by loss of peripheral hydrogen.

The Surface Core Level Shift For Lithium At The Surface Of Lithium Borate, David Wooten, Ihor Ketsman, Jie Xiao, Yaroslav B. Losovyj, J. C. Petrosky, J. Mcclory, Ya. V. Burak, V. T. Adamiv, Peter A. Dowben

Peter Dowben Publications

The shallow Li 1s core level exhibits a surface-to-bulk core level shift for the stoichiometric Li₂B₄O₇ (1 1 0) surface. Angle-resolved photoemission spectroscopy was used to identify Li1s bulk and surface core level components at binding energies –56.5 ± 0.4 and –53.7 ± 0.5 eV, respectively. We find photoemission evidence for surface states of Li₂B₄O₇ (1 1 0) that exist in the gap of the projected bulk density of states. The existence of surface states is consistent with the large surface-to-bulk core level shift for the Li 1s core.

Induced Spin Polarization Of Copper Spin 1/2 Molecular Layers, David Wisbey, Ning Wu, Danqin Feng, A. N. Caruso, J. Belot, Yaroslav B. Losovyj, Elio Vescovo, Peter A. Dowben

Peter Dowben Publications

Thin films of the metal organic molecule bis(4-cyano-2,2,6,6-tetramethyl-3,5-heptanedionato)copper(II) (or Cu(CNdpm)₂), (C₂₄H₃₆N₂O₄Cu, Cu(II)), deposited on ferromagnetic Co(111) at 40 K, exhibit a finite electron spin polarization. The spin polarization magnitude and sign for Cu(CNdpm)₂ deposited on Co(111) is coverage dependent, but deviates from the mean field expectations for a simple paramagnet on a ferromagnetic substrate. The spin asymmetry is seen to favor select molecular orbitals, consistent with the predicted single molecule density of states. The overlayer polarization observed indicates a strong influence of the ferromagnetic Co(111) substrate and some extra-molecular …

4f Hybridization And Band Dispersion In Gadolinium Thin Films And Compounds, Takashi Komesu, H.-K. Jeong, David Wooton, Yaroslav B. Losovyj, J. N. Crain, M. Bissen, F. J. Himpsel, J. C. Petrosky, Jinke Tang, Wendong Wang, I. N. Yakovkin, Peter A. Dowben

Peter Dowben Publications

There is interplay between intra-atomic orbital hybridization and extra-atomic hybridization in various gadolinium systems, which affects magnetic coupling and electron itinerancy (localization). The results do not always follow expectation. The experimental band structure of thin Gd(0001) films, grown on the Mo(112) surface, along the Γ − M does not agree with expectations even qualitatively. In particular, the dispersion of the gadolinium band, with strong 5d weight near 2 eV binding energy provides considerable evidence to support the case for 4f- 5d hybridization, with increasing 5d localization. On the other hand, there is also evidence of extra-atomic Gd 4f hybridization leading …

The Effect Of Defects On The Electronic Structure Of Long Chain Ferroelectric Polymers, Jie Xiao, Xin Zhou, Q. M. Zhang, Peter A. Dowben

Peter Dowben Publications

The apparent molecular density of states from combined photoemission and inverse photoemission spectroscopies is compared to the bulk conductivity and frequency dependent dielectric measurements for a variety of ferroelectric polymer poly(vinylidene fluoride) (PVDF) copolymers and terpolymers. While some extra chemical groups introduced into the PVDF long chains increase the measured conductivities at room temperature and can cause significant changes in the dielectric properties, few changes are observed in the overall experimental molecular density of states. The exception appears to be the very short polymer chains. The significance of this comparison is that profound changes can occur in the overall dielectric …

Search For The Lightest Scalar Top Quark In Events With Two Leptons In Pp Collisions At √S = 1.96 Tev, V. M. Abazov, Kenneth A. Bloom, Gregory Snow, D0 Collaboration

Kenneth Bloom Publications

We report results of a search for the pair production of the lightest supersymmetric partner of the top quark, t₁, using a data set corresponding to an integrated luminosity of 1 fb⁻¹ collected by the DØ detector at a pp center-of-mass energy of 1.96 TeV at the Fermilab Tevatron collider. Both scalar top quarks are assumed to decay into a b quark, a charged lepton and a scalar neutrino. The search is performed in the electron plus muon and dielectron final states. The signal topology consists of two isolated leptons, missing transverse energy, and jets. We find …

Determination Of The Strong Coupling Constant From The Inclusive Jet Cross Section In Pp Collisions At √S= 1.96 Tev, V. M. Abazov, Kenneth A. Bloom, Gregory Snow, D0 Collaboration

Kenneth Bloom Publications

We determine the strong coupling constant α_s and its energy dependence from the p_T dependence of the inclusive jet cross section in pp collisions at √s= 1.96 TeV. The strong coupling constant is determined over the transverse momentum range 50<p_T < 145 GeV. Using perturbative QCD calculations to order O(α_s³) combined with O(α_s⁴) contributions from threshold corrections, we obtain α_s(M_Z) =0.1161_-0.0048^+0.0041. This is the most precise result obtained at a hadron-hadron collider.