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Using Cox’S Proportional Hazard Models To Implement Optimal Strategies: An Example From Behavioral Ecology, Brigitte Tenhumberg, M. A. Keller, Hugh P. Possingham

School of Biological Sciences: Faculty Publications

Simple behavioral rules, or “rules of thumb,” which lead to behavior that closely approximates an optimal strategy, have generated a lot of recent interest in the field of foraging behavior. In this paper, we derive rules of thumb from a stochastic simulation model in which the foragers behave optimally. We use a particular biological system: the patch leaving behavior of a parasitoid. We simulate parasitoids whose patch leaving behavior is determined by a stochastic dynamic programming (SDP) model, while allowing parasitoids to make mistakes in their estimation of host density when arriving in a patch We use Cox’s proportional hazards …

Mean Time To Extinction Of A Metapopulation With An Allee Effect, Chad Brassil

School of Biological Sciences: Faculty Publications

The incorporation of Allee effects into a simple metapopulation extinction model reveals a large non-linear reduction in mean time to extinction with small changes in an Allee limit. The extent of this reduction is dependent on the level of migration in the metapopulation. With small amounts of migration, small changes in the Allee limit result in large changes in the meantime to extinction. With higher levels of migration, the mean time to extinction is not as sensitive to changes in the Allee limit, becoming more similar to the single population case. The metapopulation modeled here is a set of nine …

A New Lungworm In Muskoxen: An Exploration In Arctic Parasitology, Susan J. Kutz, Eric P. Hoberg, Lydden Polley

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Ruminants are vital elements of the Holarctic ecosystem. Little is known, however, of the structure or biology of their parasite fauna, particularly in North America. Global warming, coupied with increasing human activity in the Arctic, requires enhanced intemational interdisciplinary efforts to better understand the many factors, including parasites, that influence the population health of caribou, reindeer, muskoxen and wild sheep. The discovery of an unusual new genus of protostrongylid lung nematode in muskoxen from the central Canadian Arctic is described, and the intricacies of the parasite's relationship with its muskoxen definitive hosts, its gastropod intermediate hosts and the arctic environment …

Two-Center Effect On Low-Energy Electron Emission In Collisions Of 1-Mev/U Bare Ions With Atomic Hydrogen, Molecular Hydrogen, And Helium: Ii. H2 And He, Lokesh C. Tribedi, P. Richard, L. Gulya´S, M. Eugene Rudd

M. Eugene Rudd Publications

We have studied the energy and angular distributions of low-energy electron emission in collisions of bare carbon ions of 1-MeV/u energy with He and H₂ targets. The double-differential cross sections (DDCS’s) are measured for electrons with energies between 0.5 and 300 eV emitted within an angular range of 15° to 160°. The large forward-backward asymmetry observed in the angular distributions is explained in terms of the two-center effect. Single differential cross sections (SDCS’s) and total cross sections are also derived by integrating the DDCS’s over emission angles and energies. The data are compared with different theoretical calculations based on …

Two-Center Effect On Low-Energy Electron Emission In Collisions Of 1-Mev/U Bare Ions With Atomic Hydrogen, Molecular Hydrogen, And Helium. I. Atomic Hydrogen, Lokesh C. Tribedi, P. Richard, L. Gulya´S, M. Eugene Rudd, R. Moshammer

M. Eugene Rudd Publications

We have investigated ionization mechanisms in fast ion-atom collisions by measuring the low-energy electron emission cross sections in a pure three-body collision involving bare carbon ions (v=6.35 a.u.) colliding with atomic hydrogen targets. The measurements have also been extended to molecular hydrogen and helium targets. In this paper we provide the energy and angular distributions of double differential cross sections of low-energy electron emission for atomic hydrogen targets. The Slevin rf source with a high degree of dissociation was used to produce the atomic H target. It is found that the two-center effect has a major influence on …

Search For Electroweak Production Of Single Top Quarks In Pp̅ Collisions, B. Abbott

Gregory Snow Publications

We present a search for electroweak production of single top quarks in the electron+jets and muon+jets decay channels. The measurements use ≈90 pb^-1 of data from Run 1 of the Fermilab Tevatron collider, collected at 1.8 TeV with the D Ø detector between 1992 and 1995. We use events that include a tagging muon, implying the presence of a b jet, to set an upper limit at the 95% confidence level on the cross section for the s-channel process pp̅→tb+X of 39 pb. The upper limit for the t-channel processpp̅→tqb+X …

The Jacobson Radical For Analytic Crossed Products, Allan P. Donsig, Aristides Katavolos, Antonios Manoussos

Department of Mathematics: Faculty Publications

We characterise the Jacobson radical of an analytic crossed product C₀(X) ×_Ø Z^d₊, answering a question first raised by Arveson and Josephson in 1969. In fact, we characterise the Jacobson radical of analytic crossed products C₀(X) ×_Ø Z^d₊. This consists of all elements whose ‘Fourier coefficients’ vanish on the recurrent points of the dynamical system (and the first one is zero). The multi-dimensional version requires a variation of the notion of recurrence, taking into account the various degrees of freedom.

Presentation Of The Asp Distinguished Service Award To Robert L. Rausch, Eric P. Hoberg

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Over the past 50 years Robert Rausch has been at the forefront of research on the systematics, taxonomy, biogeography, epidemiology, and pathology of helminth parasites in vertebrate hosts. Research programs and projects have continually emphasized the complex interface of parasitology, sylvatic distributions of pathogens in wild mammals, and public health, whether dealing with tapeworms such as Echinococcus or Diphyllobothrium or with nematodes such as Trichinella. Most meticulous in research, contributions by Dr. Rausch have been characterized by their innovative nature, depth and scope of detail, complete articulation and examination of hypotheses, and novel insights integrating parasites and parasitism within …

Order-Disorder Phase Transitions In Kno2 , Csno2, And Tlno2 Crystals: A Molecular Dynamics Study, Chun-Gang Duan, Wai-Ning Mei, R. W. Smith, Jianjun Liu, M. M. Ossowski, John R. Hardy

John R. Hardy Papers

The order-disorder phase transitions of KNO₂ , CsNO₂, and TlNO₂ have been studied using parameter-free molecular dynamics simulation. It is found that the phase transitions in nitrites investigated are driven by the rotations of the NO₂^- ions about different axes together with displacements of cations and anions. We successfully reproduce the high-temperature phases of these nitrites, i.e., the NaCl-like structure for KNO₂ and CsCl-like structure for Cs(Tl)NO₂. Based on the investigation of the radial distribution function of the cations and anions, we explain why KNO₂ and Cs(Tl)NO₂ form quite …

So You Want To Work With Wolves?, John A. Shivik

United States Department of Agriculture Wildlife Services: Staff Publications

Growing up with three older sisters was a bit like being raised by wolves. One of their favorite games was called “stop hitting yourself.” To play, I was immobilized, and then with my arms overpowered, I was forced to repeatedly pummel my own noggin while they uttered the name of the game. Watching yourself hit yourself, feeling the pain and humiliation, yet being unable to stop is somewhat like being a federal biologist working with wolves. I’ve learned humility from my experiences but also formed the opinion that if you want to work with wolves, first consider medication; if that …

Estimation Of Red-Winged Blackbird Mortality From Toxic Bait Application, James F. Glahn, Michael L. Avery

United States Department of Agriculture Wildlife Services: Staff Publications

Application of slow-acting toxic bait is one method of reducing local populations of depredating blackbirds. Estimating numbers of birds killed in such baiting operations is difficult because affected birds die off-site and are seldom recovered. We conducted bioassays and flight pen studies of red-winged blackbirds (Agelaius phoeniceus) with a slow-acting, toxic brown rice bait to determine whether bird mortality could be predicted accurately using the Poisson and binomial discrete probability distributions. Bioassays confirmed that brown rice treated with 2% (w/w) 2-chloro-p-acetotoluidide was effective as a 1-particle lethal bait for redwings. Within a 0.2-ha flight pen, we offered this …

Design Of A Laboratory Secondary Hazard Study, David A. Goldade, Peter J. Savarie, Jerome C. Hurley, Stanley A. Gaddis, John J. Johnston

United States Department of Agriculture Wildlife Services: Staff Publications

Factors influencing the design and execution of a secondary hazard study are presented using the anticoagulant rodenticide, difethialone, as a model. Frequently, regulatory agencies require a determination of the potential hazard posed to non-target species by the application of pesticides. This hazard can occur through: 1) primary hazard, direct consumption of the bait or formulation containing the pesticide, or 2) secondary hazard, indirect consumption of the pesticide via ingestion of biological matrices such as animals or plants containing pesticide residues. In making this determination, the selection of appropriate test species as well as routes and level of exposure are critical. …

Introduction To Pesticides And Wildlife, John J. Johnston

United States Department of Agriculture Wildlife Services: Staff Publications

A pesticide is a substance intended for destroying, repelling or mitigating any animal, microorganism or plant pest. While pesticides are commonly chemical agents, biological or physical agents can also be pesticides. Many people equate the term pesticide with insecticide. However, there are a plethora of pesticides for which insects are not the target pest. Examples include herbicides, fungicides, rodenticides, acaricides, larvacides, etc. Additionally, pesticides are not limited to toxicants, but also include repellents, attractants and growth regulators (1 ) .

Pesticides are nearly ubiquitous in today's world. In agriculture, insecticides, nematicides and herbicides are applied to plants and soil to …

Chlorophacinone Residues In Rangeland Rodents: An Assessment Of The Potential Risk Of Secondary Toxicity To Scavengers, Thomas M. Primus, John D. Eisemann, George H. Matschke, Craig Ramey, John J. Johnston

United States Department of Agriculture Wildlife Services: Staff Publications

Field studies were conducted in California to assess efficacy of chlorophacinone-treated steam-rolled oats for controlling rangeland rodents. An objective of these studies was to assess the potential hazards of chlorophacinone residues in rangeland rodent carcasses and livers to mammalian and avian scavengers, especially raptors. Belding's ground squirrels, valley pocket gophers and Microtus spp. carcasses collected during the efficacy studies were analyzed for chlorophacinone residues. The method limit of detection (MLOD) for liver and carcass tissue samples averaged 0.036 μg/g and 0.034 μg/g, respectively. Chlorophacinone residues in Belding's ground squirrel (n=62) liver and carcass tissue ranged from Microtus sp. (n=3) tissue …

Major Herbicides In Ground Water: Results From The National Water-Quality Assessment, Jack . E. Barbash, Gail P. Thelin, Dana W. Kolpin, Robert J. Gilliom

United States Geological Survey: Staff Publications

To improve understanding of the factors affecting pesticide occurrence in ground water, patterns of detection were examined for selected herbicides, based primarily on results from the National Water-Quality Assessment (NAWQA) program. The NAWQA data were derived from 2227 sites (wells and springs) sampled in 20 major hydro- logic basins across the USA from 1993 to 1995. Results are presented for six high-use herbicides—atrazine (2-chloro-4-ethylamino-6-iso-propylamino- s-triazine), cyanazine (2-[4-chloro-6-ethylamino-1,3,5-triazin-2-yl]amino]-2-methylpropionitrile), simazine (2-chloro-4,6-bis- [ethylamino]-s-triazine), alachlor (2-chloro-N-[2,6-diethylphenyl]-N- [methoxymethyl]acetamide), acetochlor (2-chloro-N-[ethoxymethyl]- N-[ 2-ethyl-6-methylphenyl]acetamide), and metolachlor (2-chloro-N- [2-ethyl-6-methylphenyl]-N-[2-methoxy-1-methylethyl]acetamide)— as well as for prometon (2,4-bis[isopropylamino]-6-methoxy-s-triazine), a nonagricultural herbicide detected frequently during the study. Concentrations were <1 μg L^-1 at 98% …

Vegetation And Paleoclimate Of The Last Interglacial Period, Central Alaska, Daniel R. Muhs, Thomas A. Ager, James E. Begét

United States Geological Survey: Staff Publications

The last interglacial period is thought to be the last time global climate was signi"cantly warmer than present. New stratigraphic studies at Eva Creek, near Fairbanks, Alaska indicate a complex last interglacial record wherein periods of loess deposition alternated with periods of soil formation. The Eva Forest Bed appears to have formed about the time of or after deposition of the Old Crow tephra (dated to ~ 160 to ~ 120 ka), and is therefore correlated with the last interglacial period. Pollen, macrofossils, and soils from the Eva Forest Bed indicate that boreal forest was the dominant vegetation and precipitation …

Evolution Of Soils On Quaternary Reef Terraces Of Barbados, West Lndies, Daniel R. Muhs

United States Geological Survey: Staff Publications

Soils on uplifted Quaternary reef terraces of Barbados, ~125,000 to ~700,000 yr old, form a climo-chronosequence and show changes in physical, chemical, and mineralogical properties with terrace age. Parent materials are dust derived from the Sahara, volcanic ash from the Lesser Antilles island arc, and detrital carbonate from the underlying reef limestone. Although some terrace soils are probably eroded, soils or their remnants are redder and more clay-rich with increasing terrace age. Profile-average Al₂O₃ and Fe₂O₃ content increases with terrace age, which partially reflects the increasing clay content, but dithionite-extractable Fe also increases with …

The Pacific Island Mapping Program Of The Us Geological Survey, Frank C. Whitmore Jr.

United States Geological Survey: Staff Publications

A little-known aspect of the U.S. Geological Survey history is its involvement in preparing terrain intelligence reports during World War II. The Survey's Military Geology Unit was in charge of compiling these reports on areas of possible military operations. Maps were the main part of' these studies; they were compiled from existing maps, geologic and soils literature, aerial and ground photographs, and travelers' accounts. Compiled geologic anti soils maps served as basic data for interpretative maps on such subjects as construction materials. water supply, road and airfield siting and construction, and cross-country movement by tanks.

Evidence For Millennial-Scale Climate Change During Marine Isotope Stages 2 And 3 At Little Lake, Western Oregon, U.S.A., Laurie D. Grigg, Cathy Whitlock, Walter E. Dean

United States Geological Survey: Staff Publications

Pollen and geochemical data from Little Lake, western Oregon, suggest several patterns of millennial-scale environmental change during marine isotope stage (MIS) 2 (14,100–27,600 cal yr B.P.) and the latter part of MIS 3 (27,600–42,500 cal yr B.P.). During MIS 3, a series of transitions between warm- and cold-adapted taxa indicate that temperatures oscillated by ca. 2±–4±C every 1000–3000 yr. Highs and lows in summer insolation during MIS 3 are generally associated with the warmest and coldest intervals. Warm periods at Little Lake correlate with warm sea-surface temperatures in the Santa Barbara Basin. Changes in the strength of the subtropical high …

Central Us Earthquake Catalog For Hazard Maps Of Memphis, Tennessee, Russell L. Wheeler, Charles S. Mueller

United States Geological Survey: Staff Publications

An updated version of the catalog that was used for the current national probabilistic seismic-hazard maps would suffice for preduction of large-scale hazard maps of the Memphis urban area. Deaggregation maps provide guidance as to the area that a catalog for calculating Memphis hazard should cover. For the future, the Nuttli and local netword catalogs could be examined for earthquakes nor presenly included in the cataloge. Additional work on the aftershock removal might reduce hazard uncertainty. Graphs of decadal and annual earthquake rates suggest completeness at and above magnitude 3 for the last three or four decades. Any additional work …

Mapping Abyssal Current And Pressure Fields Under The Meandering Gulf Stream, D. Randolph Watts, Xiaoshu Qian, Karen L. Tracey

Graduate School of Oceanography Faculty Publications

Using bottom pressure measurements and current meter measurements at 3500-m depth at 12 sites under the Gulf Stream near 68°W daily optimally interpolated (OI) maps have been constructed for June 1988 to August 1990. Prior to mapping, the pressure records were leveled (referenced to the same absolute geopotential) using the current measurements under the assumption that their mean fields are geostrophic. The leveled pressures were subsequently used together with the current measurements in a multivariate, nondivergent OI mapping procedure. This procedure significantly reduced the mapping errors, because both pressure and its (geostrophic) gradient are specified as inputs. The mapped bottom …

Newsnotes

Vincentian Studies

No abstract provided.

The 6th International Conference And Workshop On Lobster Biology And Management: An Introduction, Mark J. Butler Iv

Biological Sciences Faculty Publications

Every three years or so, the International Conference and Workshop on Lobster Biology and Management (ICWL) brings together lobster scientists, fishery managers, and industry representatives from around the world for a week of scientific presentations, workshops, and discussions on lobster biology and management. The first ICWL was held in Perth, Australia, in January 1977. Its purpose was to bring together a small group of lobster researchers from the USA and Australia to discuss common issues and themes. That initial workshop spawned a continuing series of meetings that have become the international lobster conference for scientists—the equivalent of an international congress …

Weathering Crust Processes On Melting Glacier Ice (Alberta, Canada), Corinne Joanne Schuster

Theses and Dissertations (Comprehensive)

This thesis examines the relationship between the energy balance and hydrology of a glacier at the ice surface interface during the melt season. Experimental sub-catchments were established on the ablation area of the Peyto Glacier, Alberta, Canada, during the summers of 1994, 1995 and 1997. These sub-catchments were equipped with meteorological and hydrological instrumentation to examine relationships in the surface layer. Specifically, the development of a phenomenon known as the weathering crust is followed by examining the ratio between potential surface lowering (calculated from energy available for melt) and actual surface lowering (as measured in the field). This enables an …

Trachelomonas Spp. And Other Euglenophyceae Taxa In A Southeastern Virginia Lake, Harold G. Marshall

Biological Sciences Faculty Publications

Trachelomonas species from Lake Kilby, a reservoir lake in southeastern Virginia are described with supportive electron micrographs. The most abundant Trachelomonas species were T. hispida and T. volvocina. Other members of the Euglenophyceae occurring in this lake are identified.

Testing Multiple Intelligences: Comparing Evaluation By Simulation And Written Exam , Ian Weinstein

Faculty Scholarship

Written examinations play a key role in legal education. The LSAT is the most important factor in law school admissions. Once students enroll in law school, exams are used to evaluate and sort first year students. At most American law schools, a single, end of semester or end of year, timed, written, in class exam determines the grade in each first year class.' Although exams continue to play a major role throughout law school, once students are sorted at the end of first year it is often difficult for them to significantly change their place in the law school hierarchy. …

Learning Recursive Functions Refutably, Sanjay Jain, Efim Kinber, Rolf Wiehagen, Thomas Zeugmann

School of Computer Science & Engineering Faculty Publications

Learning of recursive functions refutably means that for every recursive function, the learning machine has either to learn this function or to refute it, i.e., to signal that it is not able to learn it. Three modi of making precise the notion of refuting are considered. We show that the corresponding types of learning refutably are of strictly increasing power, where already the most stringent of them turns out to be of remarkable topological and algorithmical richness. All these types are closed under union, though in different strengths. Also, these types are shown to be different with respect to their …

Reasoning Of Young Adults And Introductory Physics: What’S The Connection?, Vicki L. Plano Clark

Research in Physics Education Group

Moshman's discussion in his chapter from the Handbook of Child Psychology (1998) is very relevant to my work with young adults at UNL and to my interests in physics education. While there are many possible topics upon which I could write in this essay, one statement from this chapter in particular resonated with me and will serve as the starting point of my essay. This statement was as follows (emphasis added):

"Legal thinking may be defined as thinking aimed at determining what the law requires or forbids. It is often argued that legal education should be aimed at teaching a …

2001-2002 Lindenwood University Graduate Course Catalog, Lindenwood University

Course Catalogs

Lindenwood University Graduate Course Catalog

2001-2002 Lindenwood University Undergraduate Course Catalog, Lindenwood University

Course Catalogs

Lindenwood University Undergraduate Course Catalog