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Magnetization Precession And Domainwall Structure In Cobalt-Ruthenium-Cobalt Trilayers, Zhen Li, Ralph Skomski, Sy-Hwang Liou, Steven Michalski, Mircea Chipara, Roger D. Kirby

Physics & Astronomy Faculty Publications

The magnetization dynamics of Co(5 nm)/Ru/Co(5 nm) trilayers with Ru thicknesses from 0.3–0.6 nm is experimentally and theoretically investigated. The coupling between the Co layers is antiferromagnetic (AFM) and yields a stable AFM domain structure with frozen domain walls. Comparing high-resolution magnetic force microscopy (MFM) and pump-probe measurements, we analyze the behavior of the films for different field-strength regimes. For moderate magnetic fields, pump-probe measurements provide dynamic characterization of the coupled precessional modes in the GHz range. The dynamics at small fields is realized by the pinning of AFM domain walls at inhomogeneities. The MFM images yield a domain-wall width …

Thermal Reaction Wave Simulation Using Micro And Macro Scale Interaction Model, Andrei A. Markov, Igor A. Filimonov, Karen S. Martirosyan

Physics & Astronomy Faculty Publications

The thermal wave, propagating in a cylindrical tube, is numerically simulated. The technique is developed in order to provide the scale capturing as well as the stable algorithm for numerical simulation of the combustion wave. Based on the model kinetics scheme, the fields of temperature, mass fractions, and particle radius are presented for the various values of similarity parameters of the problem. The highly accurate method enables to control scales interaction and justifies various flow structures. The phase composition, structure, and morphology of the condensed product as well as the rate of the oxidation and phase transition are predicted using …

The Behavior Of Nanothermite Reaction Based On Bi2o3/Al, L. Wang, D. Luss, Karen S. Martirosyan

Physics & Astronomy Faculty Publications

We studied the impact of aluminum particle size and the thickness of surrounding alumina layer on the dynamic pressure discharge of nanothermite reactions in the Bi2O3/Al system. A pressure discharge from 9 to 13 MPa was generated using as-synthesized Bi2O3 nano-particles produced by combustion synthesis and Al nanoparticles with size from 3 μm to 100 nm. The maximum reaction temperature was measured to be ∼2700 °C. The estimated activation energy of the reaction was 45 kJ/mol. A very large (several orders of magnitude) difference existed between the rate of the pressure pulse release by nanothermite reactions and by thermite …

Directional Limits On Persistent Gravitational Waves Using Ligo S5 Science Data, J. Abadie, B. P. Abbott, Matthew Benacquista, Teviet Creighton, R. Grosso, J. Li, Soma Mukherjee, Soumya Mohanty, Malik Rakhmanov, Volker Quetschke, Robert Stone, Joseph D. Romano, B. Vaishnav

Physics & Astronomy Faculty Publications

The gravitational-wave (GW) sky may include nearby pointlike sources as well as stochastic backgrounds. We perform two directional searches for persistent GWs using data from the LIGO S5 science run: one optimized for pointlike sources and one for arbitrary extended sources. Finding no evidence to support the detection of GWs, we present 90% confidence level (C.L.) upper-limit maps of GW strain power with typical values between 2−20×10−50  strain2 Hz−1 and 5−35×10−49  strain2 Hz−1 sr−1 for pointlike and extended sources, respectively. The latter result is the first of its kind. We also set 90% C.L. limits on the narrow-band root-mean-square GW …

Unidirectional Invisibility Induced By Pt-Symmetric Periodic Structures, Zin Lin, Hamidreza Ramezani

Physics & Astronomy Faculty Publications

Parity-time (PT) symmetric periodic structures, near the spontaneous PT-symmetry breaking point, can act as unidirectional invisible media. In this regime, the reflection from one end is diminished while it is enhanced from the other. Furthermore, the transmission coefficient and phase are indistinguishable from those expected in the absence of a grating. The phenomenon is robust even in the presence of Kerr nonlinearities, and it can also effectively suppress optical bistabilities.

Investigation Of In-Situ Stresses In Rocks Via Acoustic Emission And The Kaiser Effect., Derrick J. Blanksma

Undergraduate Theses and Senior Projects

This paper is a proposal for designing the Kaiser In‐Situ Stress (KISS) System. The KISS System’s goal is to determine in‐situ stresses in rock formations and other subsurface rocks by means of compression‐induced Acoustic Emission (AE) and the Kaiser effect. The KISS System is a non‐destructive method of in‐situ stress determination and has received much attention in the past. To fully understand AE, the Kaiser Effect and how it relates to stress determination this paper will present the necessary theoretical background, past experimentation and results from the authors own experimentation to investigate the plausibility of AE and the Kaiser Effect …

Responding To Our Own Transgressions: An Experimental Writing Study Of Repentance, Offense Rumination, Self-Justification, And Distraction, Charlotte Vanoyen-Witvliet, Nova G. Hinman, Julie J. Exline, Timothy Brandt

Faculty Publications

This between-subjects experiment focused on offender responses to their past interpersonal transgressions in self-identified Christian undergraduates (55 M, 85 F). Participants completed pre-post measures for one of four randomly assigned 20-minute writing conditions: repentance (i.e., writing about constructive sorrow, apology, restitution, behavior change), offense rumination (i.e., negative wallowing), self-justification (i.e., externalizing blame, minimizing costs), or distraction (i.e., daily details). Offense rumination and repentance writing included the most cost-oriented language; rumination had the most negative emotion language. Mixed within (pre vs. post) X between group ANOVA interactions yielded theoretically meaningful results. Repentance reduced self-condemnation and regret while increasing conciliatory motivations toward …

Perceptions Of Heart Rate Monitor Use In High School Physical Education Classes., Julie A. Partridge, Kristi Mcclary King, Wei Ban

Faculty and Staff Scholarship

Incorporating technology into the physical education curriculum is becoming a popular strategy in which teachers can assess, motivate, and provide feedback to students regarding their physical activity participation during class. The purpose of this exploratory study was to gain a greater understanding of high school students’ perceptions of using heart rate monitors during physical education class. Qualitative data were collected through focus groups with students who had utilized heart rate monitors during the previous year of physical education class. Data were analyzed through inductive content analysis. Three major themes emerged from the data and indicated that 1) the use of …

Neural Mechanisms Of Interference And Storage In Vibrotactile Working Memory, Tyler D. Bancroft

Theses and Dissertations (Comprehensive)

Vibrotactile working memory has attracted increasing attention in recent years. Substantial research into the neural correlates has been conducted, especially using single-cell paradigms in non-human primates (Romo & Salinas, 2003). The vibrotactile working memory system uses a relatively simple neural code for the representation of stimuli, making it possible to determine when stimulus information is present in the various cortical areas thought to be involved. In humans, vibrotactile working memory displays properties (such as overwriting mechanisms of interference) that make it an ideal system for testing general theories of working memory. In the present study, we demonstrate that vibrotactile working …

Exploring Perfectionism, Rumination And Social Anxiety: Theoretical And Causal Implications, Jaclyn R. Brown

Theses and Dissertations (Comprehensive)

Clark and Wells’ (1995) cognitive model of Social Anxiety (SA) posits that those with (SA) have a strong fear of negative evaluation and engage in excessive rumination following social interactions or performances. Fear of negative evaluation is also a key component of perfectionism; perfectionism has also been correlated with rumination. The purpose of the research was to examine the relationships among SA, rumination and perfectionism across two studies. For Study 1, participants were recruited (N=232) to complete online questionnaires. Psychometrics, including factor structure, were examined. It was expected that SA and rumination, rumination and perfectionism, and SA and …

Examining Experiences Of English Literacy Development (Eld) Program From Multiple Stakeholders’ Perspectives, Hany Ibraham

Theses and Dissertations (Comprehensive)

The present study, conducted in collaboration with a public school board in southern Ontario, Canada, focused on stakeholders’ perspectives of an English Literacy Development (ELD) program offered in secondary schools within this particular board. The purpose of this research was to identify resources that would help address school absenteeism, credit accumulation and graduation needs of ELD learners, as well as to learn which factors in ELD better assist students who are refugees with school integration and in reaching their academic potentials. The research objectives were (1) to identify factors that influence integration of refugee students in school and (n) to …

Cd-Induced Responses In Plasma Ionic Regulation And Oxidative Stress In Rainbow Trout (O. Mykiss) Or Lake Whitefish (C. Clupeaformis) During Chronic Waterborne Exposure, Amanda Mancini

Theses and Dissertations (Comprehensive)

During chronic exposure to Cd or other metals, freshwater fish generally undergo physiological changes that results in acclimation, following a phase of damage and subsequent repair. The mechanisms associated with deleterious cellular effects induced by Cd throughout long-term exposures are less understood than those of acute toxicity, and may relate to an over-production of reactive oxygen species. The objectives of the present study were to examine the changes in, and relationship between, tissue-specific oxidative damage and antioxidant response, as well as plasma ionic regulation and tissue accumulation, in two freshwater salmonids throughout chronic Cd exposure. Rainbow trout (O. mykiss …

You Can’T Go To Zion With A Carnal Mind: Slackness And Culture In The Music Of Yellowman, Brent Hagerman

Theses and Dissertations (Comprehensive)

Jamaican deejay Yellowman is best known for “slackness” lyrics centred on masculine heterosexual potency, sexist objectification of women and graphic sexual narratives. Yet a deeper look at Yellowman’s life and recorded output suggests that when his slackness is read in the context of Afro-Jamaican culture, reggae history and his Rastafarian faith, a more complex interpretation of his slackness is needed. This study will draw on Carolyn Cooper’s (2001) theory that slackness is a “metaphorical revolt against law and order, an undermining of consensual standards of decency” (p. 141). Whereas the term “culture” is used in reggae to depict music that …

Effective Islamic Spiritual Care: Foundations And Practices Of Imams And Other Muslim Spiritual Caregivers, Nazila Isgandarova

Theses and Dissertations (Comprehensive)

In Canada, Muslim communities turn to Muslim spiritual caregivers, especially to imams, for help with various problems. Research has shown that many Muslim spiritual caregivers are familiar with the Arabic language and Islamic values but have limited practice in Islamic counseling and psychotherapy. This study is intended to examine the effectiveness of Muslim spiritual caregivers in the context of Canadian Muslims’ health care. Cross-sectional ethnographic research with fifteen Muslim spiritual caregivers and interviews with them were conducted.

Our results show that even though the majority of Muslim spiritual caregivers have no formal training in Western psychotherapy intervention, they nonetheless play …

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 …

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 …

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 …

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 …

Modeling Connectivity Of Black Bears In A Desert Sky Island Archipelago, Todd C. Atwood, Julie K. Young, Jon P. Beckmann, Stewart W. Breck, Jennifer A. Fike, Olin E. Rhodes Jr., Kirby D. Bristow

United States Department of Agriculture Wildlife Services: Staff Publications

Landscape features such as rivers, mountains, desert basins, roads, and impermeable man-made structures may influence dispersal and gene flow among populations, thereby creating spatial structure across the landscape. In the US–Mexico borderland, urbanization and construction of the border fence have the potential to increase genetic subdivision and vulnerability to isolation in large mammal populations by bisecting movement corridors that have enabled dispersal between adjacent Sky Island mountain ranges. We examined genetic variation in black bears (Ursus americanus) from three regions in central and southern Arizona, US, to assess genetic and landscape connectivity in the US–Mexico border Sky Islands. We found …

Partitioning Of Anthropogenic Watering Sites By Desert Carnivores., Todd C. Atwood, Tricia L. Fry, Bruce Leland

United States Department of Agriculture Wildlife Services: Staff Publications

We investigated the role of water features as focal attractors for gray foxes (Urocyon cinereoargenteus), coyotes (Canis latrans), and bobcats (Felis rufus) in west Texas to determine if they were foci for interspecific interaction. Mixed effects models indicated that species partitioned use of water features spatially and temporally. Linear models indicated factors influencing relative activity at water features varied by species. For coyotes and bobcats, the water availability model, containing days since last rainfall and nearest-neighbor distance to water was best supported by the data, with relative activity increasing with time between rainfall and distance between waters. For gray foxes, …

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

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 …

Rock Pigeon Use Of Livestock Facilities In Northern Colorado: Implications For Improving Farm Bio-Security., James C. Carlson, Larry Clark, Michael F. Antolin, M. D. Salman

United States Department of Agriculture Wildlife Services: Staff Publications

Rock pigeons (Columba livia) have been implicated in the spread of pathogens within commercial livestock facilities. Currently, there is no data characterizing pigeon habitat use and movement patterns within and among commercial livestock facilities. To better understand the capacity for pigeons to spread pathogens, we used radio-telemetry techniques to estimate the home-range, travel distance, activity, and habitat use of pigeons roosting on and off dairies and feedlots in western Weld County, Colorado. Our observations suggest that pigeons roosting on (resident) and off (nonresident) livestock facilities use habitat differently. Nonresident pigeons used larger home-range areas than did resident pigeons. Nonresident pigeons …

Absence Of Mycobacterium Bovis In Feral Swine (Sus Scrofa) From The Southern Texas Border Region., Tyler A. Campbell, David B. Long, Luiz R. Bazan, Bruce V. Thomsen, Suelee Robbe-Austerman, Ronald B. Davey, Liza A. Soliz, Seth Swafford, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Free-ranging wildlife, such as feral swine (Sus scrofa), harbor a variety of diseases that are transmissible to livestock and could negatively impact agricultural production. Information is needed regarding the exposure and infection rates of Mycobacterium bovis and many other diseases and parasites in feral swine occurring in the Texas border region. Our main objective was to determine exposure rates and possible infection rates of M. bovis in feral swine by opportunistically sampling animals from the Texas border region. From June to September 2010, we obtained samples from 396 feral swine and tested 98 samples for M. bovis by histopathology and …

Natal Colony Site Fidelity Of Herring Gulls At Sandusky Bay, Ohio., Bruce N. Buckingham, Benjamin Bacak

United States Department of Agriculture Wildlife Services: Staff Publications

We studied three Herring Gull (Larus argentatus) colonies in the Sandusky Bay area, Sandusky, OH, between 1981 and 2006. During this period, we banded 24,000 nestlings and received reports of 347 recovered bands. Forty-nine of these band recoveries were as adults recovered during the nesting season as far as 890 km from their natal colony. Gulls were also captured at five other colonies located in the Great Lakes. Gulls recovered outside the original 10-min block of banding accounted for 47 percent of the returns. We hypothesize that half of the recoveries of adult Herring Gulls during the nesting season occurred …

Domestic Calf Mortality And Producer Detection Rates In The Mexican Wolf Recovery Area: Implications For Livestock Management And Carnivore Compensation Schemes., Stewart W. Breck, Bryan M. Kluever, Michael Panasci, John Oakleaf, Terry Johnson, Warren B. Ballard, Larry Howery, David L. Bergman

United States Department of Agriculture Wildlife Services: Staff Publications

Conserving large carnivores throughout the world will often require that they share the landscape with livestock. Minimizing depredations and increasing tolerance by livestock producers will be critical for conservation efforts. To investigate factors influencing calf mortality and producer detection rates (i.e., number of livestock killed by predators, found by producers, and correctly classified as to cause of death), we monitored radio-tagged domestic calves at two sites in the Mexican wolf recovery area (East Eagle [EE] and Adobe Ranch [AR]). Study areas differed in grazing practices, density of predators (mountain lions, black bears, coyotes, and Mexican wolves), and amount of effort …

A Review And Synthesis Of Bird And Rodent Damage Estimates To Select California Crops, Karen Gebhardt, Aaron M. Anderson, Katy N. Kirkpatrick, Stephanie A. Shwiff

United States Department of Agriculture Wildlife Services: Staff Publications

A comprehensive literature review was conducted to identify the magnitude of bird and rodent damage to 19 economically important crops in California. Interviews with agriculture experts provided additional information about damages. Monte Carlo simulations were used to derive summary estimates of damages to each crop. A meta-analysis indicated that summary damage estimates from expert interviews were higher than estimates from field studies and surveys. It was also found that there has been a downward trend over time in damages to almonds and grapes. The results of our study indicate that damages from bird and rodents remain high for many crops …

Clinical And Pathologic Responses Of American Crows (Corvus Brachyrhynchos) And Fish Crows (C Ossifragus) To Experimental West Nile Virus Infection, N. M. Nemeth, B. V. Thomsen, T. R. Spraker, J. M. Benson, A. M. Bosco-Lauth, P. T. Oesterle, J. M. Bright, J. P. Muth, T. W. Campbell, T. L. Gidlewski, R. A. Bowen

United States Department of Agriculture Wildlife Services: Staff Publications

West Nile virus (WNV)-associated disease has a range of clinical manifestations among avian taxa, the reasons for which are not known. Species susceptibility varies within the avian family Corvidae, with estimated mortality rates ranging from 50 to 100%. We examined and compared virologic, immunologic, pathologic, and clinical responses in 2 corvid species, the American crow (Corvus brachyrhynchos) and the fish crow (C ossifragus), following experimental WNV inoculation. Unlike fish crows, which remained clinically normal throughout the study, American crows succumbed to WNV infection subsequent to dehydration, electrolyte and pH imbalances, and delayed or depressed humoral immune …

Assessment Of Human-Coyote Conflicts: City And County Of Broomfield, Colorado, Stan Grant, Julie K. Young, Seth Riley

United States Department of Agriculture Wildlife Services: Staff Publications

In the summer of 2011, the Anthem Highlands neighborhood of the City and County of Broomfield (Broomfield), Colorado experienced multiple serious incidents between humans and coyotes. Broomfield has a detailed policy about coexisting with wildlife in general, and coyotes in particular, that includes extensive public education and outreach. Because of the serious nature of the incidents, the Colorado Division of Parks and Wildlife, with assistance from USDA-Wildlife Services and in collaboration with Broomfield, engaged in coyote removal efforts. One coyote was lethally removed after the first incident, another was shot after the second incident, 8 coyotes were lethally removed (7 …

Testing The Terrain Hypothesis: Canada Geese See Their World Laterally And Obliquely, Esteban Fernández-Juricic, Bret A. Moore, Megan Doppler, Joseph Freeman, Bradley F. Blackwelll, Steven L. Lima, Travis L. Devault

United States Department of Agriculture Wildlife Services: Staff Publications

The distribution of ganglion cells in the retina determines the specific regions of the visual field with high visual acuity, and thus reflects the perception of a species’ visual environment. The terrain hypothesis proposes that animals living in open areas should have a horizontal visual streak across the retina with high ganglion cell density to increase visual acuity along the horizon. We tested this hypothesis in Canada geese (Branta canadensis) by assessing retinal topography, visual field configuration, and scanning behavior. We found that geese have an oblique rather than a horizontal visual streak across the retina: from a …