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2011

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Research And Development In The U.S. Army Corps Of Engineers: Improving The Common Stock Of Knowledge, Damon Manders Jan 2011

Research And Development In The U.S. Army Corps Of Engineers: Improving The Common Stock Of Knowledge, Damon Manders

United States Army Corps of Engineers, Omaha District

When Charles A. Camillo, the U.S. Army Corps of Engineers Mississippi Valley Division and U.S. Army Engineer Research and Development Center (ERDC) historian, approached me in 2007 about the possibility of working on a history of ERDC, I was excited about the potential of the project. He outlined a volume that would cover scientific research in engineering, hydraulics, computer science, topography, environmental science, and other technical fields. As one raised by an engineer in a town with one of the highest concentrations of physicists, engineers, and computer developers in the country — Huntsville, Alabama — and as someone who had …

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Short-Term Facilitation May Stabilize Parametric Working Memory Trace, Vladimir Itskov, David Hansel, Misha Tsodyks Jan 2011

Short-Term Facilitation May Stabilize Parametric Working Memory Trace, Vladimir Itskov, David Hansel, Misha Tsodyks

Department of Mathematics: Faculty Publications

Networks with continuous set of attractors are considered to be a paradigmatic model for parametric working memory (WM), but require fine tuning of connections and are thus structurally unstable. Here we analyzed the network with ring attractor, where connections are not perfectly tuned and the activity state therefore drifts in the absence of the stabilizing stimulus. We derive an analytical expression for the drift dynamics and conclude that the network cannot function as WM for a period of several seconds, a typical delay time in monkey memory experiments. We propose that short-term synaptic facilitation in recurrent connections significantly improves the …

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Comparative Analysis Of The Biaxial Mechanical Behavior Of Carotid Wall Tissue And Biological And Synthetic Materials Used For Carotid Patch Angioplasty, Alexey Kamenskiy, Iraklis I. Pipinos, Jason N. Mactaggart, Syed A. Jaffar Kazmi, Yuris A. Dzenis Jan 2011

Comparative Analysis Of The Biaxial Mechanical Behavior Of Carotid Wall Tissue And Biological And Synthetic Materials Used For Carotid Patch Angioplasty, Alexey Kamenskiy, Iraklis I. Pipinos, Jason N. Mactaggart, Syed A. Jaffar Kazmi, Yuris A. Dzenis

Department of Mechanical and Materials Engineering: Faculty Publications

Patch angioplasty is the most common technique used for the performance of carotid endarterectomy. A large number of patching materials are available for use while new materials are being continuously developed. Surprisingly little is known about the mechanical properties of these materials and how these properties compare with those of the carotid artery wall. Mismatch of the mechanical properties can produce mechanical and hemodynamic effects that may compromise the long-term patency of the endarterectomized arterial segment. The aim of this paper was to systematically evaluate and compare the biaxial mechanical behavior of the most commonly used patching materials. We compared …

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Frequency Shifts In Plate Crystal Resonators Induced By Electric, Magnetic, Or Mechanical Fields In Surface Films, Nan Liu, J.S. Yang, Yuantai Hu, Xuedong Chen, Wei Jiang Jan 2011

Frequency Shifts In Plate Crystal Resonators Induced By Electric, Magnetic, Or Mechanical Fields In Surface Films, Nan Liu, J.S. Yang, Yuantai Hu, Xuedong Chen, Wei Jiang

Department of Mechanical and Materials Engineering: Faculty Publications

We study frequency shifts in plate crystal resonators with surface films. The films are multiphysical, including the effects of inertia, stiffness, intrinsic stress, piezoelectric coupling, and piezomagnetic coupling. Mindlin’s two-dimensional equations for a crystal plate with two elastic surface films are generalized to include the multiphysical effects of the films. They are used to study thickness-shear vibrations of a rotated Y-cut quartz plate with initial fields resulting from the mechanical, electric, and magnetic fields in the surface films. Frequency shifts caused by the initial fields are calculated and examined. Results show that plate crystal resonators with multiphysical surface films may …

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A Few Transient Effects In At-Cut Quartz Thickness-Shear Resonators, Runyu Zhang, Hongping Hu Jan 2011

A Few Transient Effects In At-Cut Quartz Thickness-Shear Resonators, Runyu Zhang, Hongping Hu

Department of Mechanical and Materials Engineering: Faculty Publications

We study a few transient effects of AT-cut quartz thickness-shear resonators, including resonator turning on and turning off as well as voltage amplitude and frequency fluctuations. Mindlin’s two-dimensional plate equations are used and solved analytically. Both a sudden change and a gradual change of the driving voltage are studied. It is found that for a resonator with a frequency of 1.649430868 MHz and material quality factor of Q = 105, the characteristic time scale of the transient effects is of the order of 0.1 s.

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Modeling Dynamic Fracture And Damage In A Fiber-Reinforced Composite Lamina With Peridynamics, Wenke Hu, Youn Doh Ha, Florin Bobaru Jan 2011

Modeling Dynamic Fracture And Damage In A Fiber-Reinforced Composite Lamina With Peridynamics, Wenke Hu, Youn Doh Ha, Florin Bobaru

Department of Mechanical and Materials Engineering: Faculty Publications

We propose a peridynamic formulation for a unidirectional fiber-reinforced composite lamina based on homogenization and mapping between elastic and fracture parameters of the micro-scale peridynamic bonds and the macro-scale parameters of the composite. The model is then used to analyze the splitting mode (mode II) fracture in dynamic loading of a 0° lamina. Appropriate scaling factors are used in the model in order to have the elastic strain energy, for a fixed nonlocal interaction distance (the peridynamic horizon), match the classical one. No special criteria for splitting failure are required to capture this fracture mode in the lamina. Convergence studies …

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Adaptive Refinement And Multiscale Modeling In 2d Peridynamics, Florin Bobaru, Youn Doh Ha Jan 2011

Adaptive Refinement And Multiscale Modeling In 2d Peridynamics, Florin Bobaru, Youn Doh Ha

Department of Mechanical and Materials Engineering: Faculty Publications

The original peridynamics formulation uses a constant nonlocal region, the horizon, over the entire domain. We propose here adaptive refinement algorithms for the bond-based peridynamic model for solving statics problems in two dimensions that involve a variable horizon size. Adaptive refinement is an essential ingredient in concurrent multiscale modeling, and in peridynamics changing the horizon is directly related to multiscale modeling. We do not use any special conditions for the “coupling” of the large and small horizon regions, in contrast with other multiscale coupling methods like atomistic-to-continuum coupling, which require special conditions at the interface to eliminate ghost forces in …

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Mechanisms For Decisions About The Future, Jeffrey R. Stevens Jan 2011

Mechanisms For Decisions About The Future, Jeffrey R. Stevens

Jeffrey Stevens Publications

Evolutionary and psychological perspectives on decision making remain largely separate endeavors. The bounded rationality approach integrates these two perspectives by focusing on simple, plausible mechanisms of decision making and the cognitive capacities needed to implement these mechanisms. Decisions about the future provide a class of decisions that lend themselves to a bounded rationality approach. Though many different mechanisms may exist for making decisions about the future, only a subset of these mechanisms actually require a representation of the future. The bounded rationality approach helps focus on the cognitive capacities and decision mechanisms that are necessary for a full understanding of …

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Experimental Observation Of Time-Delays Associated With Electric Matteucci–Pozzi Phase Shifts, Shawn A. Hilbert, Adam Caprez, Herman Batelaan Jan 2011

Experimental Observation Of Time-Delays Associated With Electric Matteucci–Pozzi Phase Shifts, Shawn A. Hilbert, Adam Caprez, Herman Batelaan

Department of Physics and Astronomy: Faculty Publications

In 1985, Matteucci and Pozzi (1985 Phys. Rev. Lett. 54 2469) demonstrated the presence of a quantum mechanical phase shift for electrons passing a pair of oppositely charged biprism wires. For this experimental arrangement no forces deflect the electrons. Consequently, the result was reported as a non-local type-2 Aharonov–Bohm effect. Boyer (2002 Found. Phys. 32 41–50; 1987 Nuovo Cimento B 100 685–701) showed theoretically that the Matteucci–Pozzi effect could be associated with a time delay caused by a classical force. We present experimental data that confirm the presence of a time delay. This result is in contrast to the situation …

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Transverse Quantum Stern–Gerlach Magnets For Electrons, Scot Mcgregor, Roger Bach, Herman Batelaan Jan 2011

Transverse Quantum Stern–Gerlach Magnets For Electrons, Scot Mcgregor, Roger Bach, Herman Batelaan

Department of Physics and Astronomy: Faculty Publications

In the Stern–Gerlach experiment, silver atoms were separated according to their spin state (Gerlach and Stern 1922 Z. Phys. 9 353–355). This experiment demonstrates the quantization of spin and relies on the classical description of motion. However, so far, no design has led to a functional Stern–Gerlach magnet for free electrons. Bohr and Pauli showed in the 1930 Solvay conference that Stern–Gerlach magnets for electrons cannot work, at least if the design is based on classical trajectories (Pauli W 1932 Proc. of the 6th Solvay Conf. 2 (1930) (Brussels: Gauthier-Villars) pp 183–86, 217–20, 275–80; Pauli W 1964 Collected Scientific Papers …

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Quantum Description And Properties Of Electrons Emitted From Pulsed Nanotip Electron Sources, Pavel Lougovski, Herman Batelaan Jan 2011

Quantum Description And Properties Of Electrons Emitted From Pulsed Nanotip Electron Sources, Pavel Lougovski, Herman Batelaan

Department of Physics and Astronomy: Faculty Publications

We present a quantum calculation of the electron degeneracy for electron sources. We explore quantum interference of electrons in the temporal and spatial domain and demonstrate how it can be utilized to characterize a pulsed electron source. We estimate effects of Coulomb repulsion on two-electron interference and show that currently available nano tip pulsed electron sources operate in the regime where the quantum nature of electrons can be made dominant.

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In Memoriam Robert Katz (1917–2011), Michael P. R. Waligorski, Francis A. Cucinotta Jan 2011

In Memoriam Robert Katz (1917–2011), Michael P. R. Waligorski, Francis A. Cucinotta

Department of Physics and Astronomy: Faculty Publications

Dr. Robert (Bob) Katz, emeritus professor of physics at the University of Nebraska, author of the Katz Model, a deceptively simple but profound parametric model of the action of charged particles on physical and biological systems, died peacefully at his home at Lincoln, NE, on March 12, 2011, after a brief illness. Bob, born in New York City in 1917, and his sister Gladys, were of immigrant Russian Jewish descent. Their parents owned a delicatessen in the Bronx, not far from the Yankee Stadium, where, as Bob recalled, Babe Ruth stopped by for hot dogs, a huge man driving a …

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Colossal Negative Magnetoresistance In Dilute Fluorinated Graphene, X. Hong, S.-H. Cheng, C. Herding, J. Zhu Jan 2011

Colossal Negative Magnetoresistance In Dilute Fluorinated Graphene, X. Hong, S.-H. Cheng, C. Herding, J. Zhu

Xia Hong Publications

Adatoms offer an effective route to modify and engineer the properties of graphene. In this work, we create dilute fluorinated graphene using a clean, controlled, and reversible approach. At low carrier densities, the system is strongly localized and exhibits an unexpected, colossal negative magnetoresistance. The zero-field resistance is reduced by a factor of 40 at the highest field of 9 T and shows no sign of saturation. Unusual staircaselike field dependence is observed below 5 K. The magnetoresistance is highly anisotropic. These observations cannot be explained by existing theories, but likely require adatom-induced magnetism and/or a metal-insulator transition driven by …

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Overcoming The Spin-Multiplicity Limit Of Entropy By Means Of Lattice Degrees Of Freedom: A Minimal Model, Tathagata Mukherjee, Steven A. Michalski, Ralph Skomski, David J. Sellmyer, Christian Binek Jan 2011

Overcoming The Spin-Multiplicity Limit Of Entropy By Means Of Lattice Degrees Of Freedom: A Minimal Model, Tathagata Mukherjee, Steven A. Michalski, Ralph Skomski, David J. Sellmyer, Christian Binek

Ralph Skomski Publications

The discovery of the giant magnetocaloric effect with isothermal field-induced entropy change beyond the spin-multiplicity limit gave rise to some indistinctness in the literature regarding the applicability of fundamental thermodynamics in data analysis. Those misleading interpretations concerning, for instance, the rigorousness of phenomenological thermodynamics are clarified here. Specifically, it is shown that the Maxwell relation incorporates contributions from the spin degrees of freedom and potential lattice degrees of freedom into the isothermal entropy change. A minimalist model involving pairs of exchange-coupled, mobile Ising spins is investigated. It is explicitly shown that lattice degrees of freedom can be activated via applied …

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Ultrafast Rempi In Benzene And The Monohalobenzenes Without The Focal Volume Effect, Timothy D. Scarborough, James Strohaber, David B. Foote, Collin J. Mcacy, Cornelis J. Uiterwaal Jan 2011

Ultrafast Rempi In Benzene And The Monohalobenzenes Without The Focal Volume Effect, Timothy D. Scarborough, James Strohaber, David B. Foote, Collin J. Mcacy, Cornelis J. Uiterwaal

C.J.G.J. Uiterwaal Publications

We report on the photoionization and photofragmentation of benzene (C6H6) and of the monohalobenzenes C6H5–X (X = F, Cl, Br, I) under intense-field, single-molecule conditions. We focus 50-fs, 804-nm pulses from a Ti:sapphire laser source, and record ion mass spectra as a function of intensity in the range ~1013 W/cm2 to ~1015 W/cm2. We count ions that were created in the central, most intense part of the focal area; ions from other regions are rejected. For all targets, stable parent ions (C6H5X+) are …

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Metallic And Insulating Oxide Interfaces Controlled By Electronic Correlations, H. W. Jang, D. A. Felker, C. W. Bark, Y. Wang, Manish K. Niranjan, C. T. Nelson, Y. Zhang, D. Su, C. M. Folkman, S. H. Baek, S. Lee, K. Janicka, Y. Zhu, X. Q. Pan, D. D. Fong, Evgeny Y. Tsymbal, M. S. Rzchowski, Chang-Beom Eom Jan 2011

Metallic And Insulating Oxide Interfaces Controlled By Electronic Correlations, H. W. Jang, D. A. Felker, C. W. Bark, Y. Wang, Manish K. Niranjan, C. T. Nelson, Y. Zhang, D. Su, C. M. Folkman, S. H. Baek, S. Lee, K. Janicka, Y. Zhu, X. Q. Pan, D. D. Fong, Evgeny Y. Tsymbal, M. S. Rzchowski, Chang-Beom Eom

Evgeny Tsymbal Publications

The formation of two-dimensional electron gases (2DEGs) at complex oxide interfaces is directly influenced by the oxide electronic properties. We investigated how local electron correlations control the 2DEG by inserting a single atomic layer of a rare-earth oxide (RO) [(R is lanthanum (La), praseodymium (Pr), neodymium (Nd), samarium (Sm), or yttrium (Y)] into an epitaxial strontium titanate oxide (SrTiO3) matrix using pulsed-laser deposition with atomic layer control. We find that structures with La, Pr, and Nd ions result in conducting 2DEGs at the inserted layer, whereas the structures with Sm or Y ions are insulating. Our local …

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Transport Spin Polarization Of High-Curie Temperature Mnbi Films, Parashu Kharel, P. Thapa, Pavel V. Lukashev, Renat F. Sabirianov, Evgeny Y. Tsymbal, D. J. Sellmyer, Boris Nadgorny Jan 2011

Transport Spin Polarization Of High-Curie Temperature Mnbi Films, Parashu Kharel, P. Thapa, Pavel V. Lukashev, Renat F. Sabirianov, Evgeny Y. Tsymbal, D. J. Sellmyer, Boris Nadgorny

Evgeny Tsymbal Publications

We report on the study of the structural, magnetic, and transport properties of highly textured MnBi films with the Curie temperature of 628 K. In addition to detailed measurements of resistivity and magnetization, we measure transport spin polarization of MnBi by Andreev reflection spectroscopy and perform fully relativistic band-structure calculations of MnBi. A spin polarization from 51% ± 1% to 63% ± 1% is observed, consistent with the calculations and with an observation of a large magnetoresistance in MnBi contacts. The band-structure calculations indicate that in spite of almost identical densities of states at the Fermi energy, the large disparity …

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A Giant Tunneling Electroresistance Effect Driven By Electrically Controlled Spin Valve At A Complex Oxide Interface, John D. Burton, Evgeny Y. Tsymbal Jan 2011

A Giant Tunneling Electroresistance Effect Driven By Electrically Controlled Spin Valve At A Complex Oxide Interface, John D. Burton, Evgeny Y. Tsymbal

Evgeny Tsymbal Publications

A giant tunneling electroresistance effect may be achieved in a ferroelectric tunnel junction by exploiting the magnetoelectric effect at the interface between the ferroelectric barrier and a magnetic La1-xSrxMnO3 electrode. Using first-principles density-functional theory we demonstrate that a few magnetic monolayers of La1-xSrxMnO3 near the interface act, in response to ferroelectric polarization reversal, as an atomic-scale spin valve by filtering spin-dependent current. This produces more than an order of magnitude change in conductance, and thus constitutes a giant resistive switching effect.

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Interface Between Black-Footed Ferret Research And Operational Conservation., Dean E. Biggins, Travis M. Livieri, Stewart W. Breck Jan 2011

Interface Between Black-Footed Ferret Research And Operational Conservation., Dean E. Biggins, Travis M. Livieri, Stewart W. Breck

United States Department of Agriculture Wildlife Services: Staff Publications

Questions and problems that emerged during operational conservation of black-footed ferrets (Mustela nigripes)have been addressed by a wide variety of studies. Early results from such studies often were communicated orally during meetings of recovery groups and in written form using memoranda, unpublished reports, and theses. Typically, implementation of results preceded their publication in widely distributed journals. Many of these studies eventually were published in journals, and we briefly summarize the contents of 8 volumes and special features of journals that have been dedicated to the biology of ferrets and issues in ferret recovery. This year marks the 30th anniversary of …

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Active Use Of Coyotes (Canis Latrans) To Detect Bovine Tuberculosis In Northeastern Michigan, Usa, Are R. Berentsen, Michael R. Dunbar, Shylo R. Johnson, S. Robbe-Austerman, L. Martinez, R. L. Jones Jan 2011

Active Use Of Coyotes (Canis Latrans) To Detect Bovine Tuberculosis In Northeastern Michigan, Usa, Are R. Berentsen, Michael R. Dunbar, Shylo R. Johnson, S. Robbe-Austerman, L. Martinez, R. L. Jones

United States Department of Agriculture Wildlife Services: Staff Publications

Bovine tuberculosis (bTB) is endemic in white-tailed deer (Odocoileus virginianus) in northeastern Michigan, USA, and research suggests transmission to cattle. Prevalence of the disease in deer is estimated at 1.8%, but as prevalence decreases the difficulty of detection increases. Research suggests coyotes (Canis latrans) have a higher prevalence of bTB in Michigan than deer and sampling coyotes may be a more efficient surveillance tool to detect presence or spread of the disease. Coyotes possess suitable ecological characteristics to serve as a sentinel species, assuming transmission between coyotes is not significant. The question of whether free-ranging coyotes shed Mycobacterium bovis, the …

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White-Tailed Deer Incidents With U.S. Civil Aircraft, Kirsten M. Biondi, Jerrold L. Belant, James A. Martin, Travis L. Devault, Guiming Wang Jan 2011

White-Tailed Deer Incidents With U.S. Civil Aircraft, Kirsten M. Biondi, Jerrold L. Belant, James A. Martin, Travis L. Devault, Guiming Wang

United States Department of Agriculture Wildlife Services: Staff Publications

Aircraft incidents with ungulates cause substantial economic losses and pose risks to human safety. We analyzed 879 white-tailed deer (Odocoileus virginianus) incidents with United States civil aircraft from 1990 to 2009 reported in the Federal Aviation Administration National Wildlife Strike Database. During that time, deer incidents followed a quadratic response curve, peaking in 1994 and declining thereafter. There appeared to be some seasonal patterning in incident frequency, with deer incidents increasing overall from January to November, and peaking in October and November (30.7%). Most incidents (64.8%) occurred at night, but incident rates were greatest (P 0.001) at dusk. Landing-roll represented …

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The Carrot Or The Stick? Evaluation Of Education And Enforcement As Management Tools For Human-Wildlife Conflicts., Sharon Baruch-Mordo, Stewart W. Breck, Kenneth R. Wilson, John Broderick Jan 2011

The Carrot Or The Stick? Evaluation Of Education And Enforcement As Management Tools For Human-Wildlife Conflicts., Sharon Baruch-Mordo, Stewart W. Breck, Kenneth R. Wilson, John Broderick

United States Department of Agriculture Wildlife Services: Staff Publications

Evidence-based decision-making is critical for implementing conservation actions, especially for human-wildlife conflicts, which have been increasing worldwide. Conservation practitioners recognize that long-term solutions should include altering human behaviors, and public education and enforcement of wildlife-related laws are two management actions frequently implemented, but with little empirical evidence evaluating their success. We used a system where human-black bear conflicts were common, to experimentally test the efficacy of education and enforcement in altering human behavior to better secure attractants (garbage) from bears. We conducted 3 experiments in Aspen CO, USA to evaluate: 1) on-site education in communal dwellings and construction sites, 2) …

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Vulture Flight Behavior And Implications For Aircraft Safety, Michael L. Avery, John S. Humphrey, Trey S. Daughtery, Justin W. Fischer, Michael P. Milleson, Eric A. Tillman, William E. Bruce, W. David Walter Jan 2011

Vulture Flight Behavior And Implications For Aircraft Safety, Michael L. Avery, John S. Humphrey, Trey S. Daughtery, Justin W. Fischer, Michael P. Milleson, Eric A. Tillman, William E. Bruce, W. David Walter

United States Department of Agriculture Wildlife Services: Staff Publications

Growing vulture populations represent increasing hazards to civil and military aircraft. To assess vulture flight behavior and activity patterns at the Marine Corps Air Station in Beaufort, South Carolina, we equipped 11 black vultures (Coragyps atratus) and 11 turkey vultures (Cathartes aura) with solarpowered Global Positioning System (GPS) satellite transmitters during a 2-year study (1 Oct 2006–30 Sep 2008). Turkey vultures had larger seasonal home ranges than did black vultures, and 2 turkey vultures made round-trips to Florida. Black vultures consistently spent less time in flight (8.4%) than did turkey vultures (18.9%), and black vultures flew at higher altitudes than …

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Acetaminophen And Zinc Phosphide For Lethal Management Of Invasive Lizards Ctenosaura Similis , Michael L. Avery, John D. Eisemann, Kandy L. Keacher, Peter J. Savarie Jan 2011

Acetaminophen And Zinc Phosphide For Lethal Management Of Invasive Lizards Ctenosaura Similis , Michael L. Avery, John D. Eisemann, Kandy L. Keacher, Peter J. Savarie

United States Department of Agriculture Wildlife Services: Staff Publications

Reducing populations of invasive lizards through trapping and shooting is feasible in many cases but effective integrated management relies on a variety of tools, including toxicants. In Florida, using wild-caught non-native black spiny-tailed iguanas Ctenosaura similis, we screened acetaminophen and zinc phosphide to determine their suitability for effective population management of this prolific invasive species. Of the animals that received acetaminophen, none died except at the highest test dose, 240 mg per lizard, which is not practical for field use. Zinc phosphide produced 100% mortality at dose levels as little as 25 mg per lizard, equivalent to about 0.5% in …

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Hair Of The Dog: Obtaining Samples From Coyotes And Wolves Noninvasively, David E. Ausband, Julie K. Young, Barbara Fannin, Michael S. Mitchell, Jennifer L. Stenglen, Lizette P. Waits, John A. Shivik Jan 2011

Hair Of The Dog: Obtaining Samples From Coyotes And Wolves Noninvasively, David E. Ausband, Julie K. Young, Barbara Fannin, Michael S. Mitchell, Jennifer L. Stenglen, Lizette P. Waits, John A. Shivik

United States Department of Agriculture Wildlife Services: Staff Publications

Canids can be difficult to detect and their populations difficult to monitor. We tested whether hair samples could be collected from coyotes (Canis latrans) in Texas, USA and gray wolves (C. lupus) in Montana, USA using lure to elicit rubbing behavior at both man-made and natural collection devices. We usedmitochondrial and nuclearDNA to determine whether collected hair samples were from coyote, wolf, or nontarget species. Both coyotes and wolves rubbed on man-made barbed surfaces but coyotes in Texas seldom rubbed on hanging barbed surfaces. Wolves in Montana showed a tendency to rub at stations where natural material collection devices (sticks …

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Wild Dogma Ii: The Role And Implications Of Wild Dogma For Wild Dog Management In Australia., Benjamin L. Allen, Richard M. Engeman, Lee R. Allen Jan 2011

Wild Dogma Ii: The Role And Implications Of Wild Dogma For Wild Dog Management In Australia., Benjamin L. Allen, Richard M. Engeman, Lee R. Allen

United States Department of Agriculture Wildlife Services: Staff Publications

The studies of Allen (2011) and Allen et al. (2011) recently examined the methodology underpinning claims that dingoes provide net benefits to biodiversity by suppressing foxes and cats. They found most studies to have design flaws and/or observational methods that preclude valid interpretations from the data, describing most of the current literature as ‘wild dogma’. In this short supplement, we briefly highlight the roles and implications of wild dogma for wild dog management in Australia. We discuss nomenclature, and the influence that unreliable science can have on policy and practice changes related to apex predator management

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Wild Dogma: An Examination Of Recent "Evidence" For Dingo Regulation Of Invasive Mesopredator Release In Australia., Benjamin L. Allen, Richard M. Engeman, Lee R. Allen Jan 2011

Wild Dogma: An Examination Of Recent "Evidence" For Dingo Regulation Of Invasive Mesopredator Release In Australia., Benjamin L. Allen, Richard M. Engeman, Lee R. Allen

United States Department of Agriculture Wildlife Services: Staff Publications

There is growing interest in the role that apex predators play in shaping terrestrial ecosystems and maintaining trophic cascades. In line with the mesopredator release hypothesis, Australian dingoes (Canis lupus dingo and hybrids) are assumed by many to regulate the abundance of invasive mesopredators, such as red foxes Vulpes vulpes and feral cats Felis catus, thereby providing indirect benefits to various threatened vertebrates. Several recent papers have claimed to provide evidence for the biodiversity benefits of dingoes in this way. Nevertheless, in this paper we highlight several critical weaknesses in the methodological approaches used in many of these reports, including …

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Nilgai Antelope In Northern Mexico As A Possible Carrier For Cattle Fever Ticks And Babesia Bovis And Babesia Bigemina., E M. Cardenas-Canales, J. Alfonso Ortega-Santos, Tyler A. Campbell, Zeferino Garcia-Vaquez, Antonio Cantu-Covarrubias, Julio V. Figueroa-Millian, Randy W. Deyoung, David G. Hewitt, Fred C. Bryant Jan 2011

Nilgai Antelope In Northern Mexico As A Possible Carrier For Cattle Fever Ticks And Babesia Bovis And Babesia Bigemina., E M. Cardenas-Canales, J. Alfonso Ortega-Santos, Tyler A. Campbell, Zeferino Garcia-Vaquez, Antonio Cantu-Covarrubias, Julio V. Figueroa-Millian, Randy W. Deyoung, David G. Hewitt, Fred C. Bryant

United States Department of Agriculture Wildlife Services: Staff Publications

Of 20 blood samples from nilgais from Me´ xico, five were polymerase chain reaction-positive for Babesia bigemina and one for Babesia bovis. Positive samples had the expected 170 (B. bigemina) and 291 (B. bovis) base pairs and were identical to Gen-Bank B. bigemina accession S45366 and B. bovis M38218.

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Diseases And Parasites, Kurt C. Vercauteren, Tyler A. Campbell Jan 2011

Diseases And Parasites, Kurt C. Vercauteren, Tyler A. Campbell

United States Department of Agriculture Wildlife Services: Staff Publications

No abstract provided.

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Efficacy Of The Boar-Operated-System To Deliver Baits To Feral Swine., Tyler A. Campbell, David B. Long, Giovanna Massei Jan 2011

Efficacy Of The Boar-Operated-System To Deliver Baits To Feral Swine., Tyler A. Campbell, David B. Long, Giovanna Massei

United States Department of Agriculture Wildlife Services: Staff Publications

Feral swine (Sus scrofa) pose a significant disease threat to livestock and humans. Emerging technologies to reduce feral swine disease transmission risks include fertility control, vaccination, and toxicants. However, for these technologies to be appropriate for field application, a feral swine-specific oral delivery system is needed. We used two field trials to generate information related to appropriate field application of the Boar-Operated-System (BOSTM), an oral delivery system designed to provide bait access only to feral swine. Our objectives were to determine whether pre-baiting BOSTM units increased bait removal and to evaluate the proportion of feral swine and non-target animals that …

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