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Pharmacokinetics and tissue withdrawal study of tulathromycin in North American bison (Bison bison) and white-tailed deer (Odocoileus virginianus) using liquid chromatography-mass spectrometry2014 February 1900 (has links)
Tulathromycin is a macrolide antibiotic approved for use in cattle and swine respiratory disease. Extra-label use of tulathromycin occurs in bison and deer and significant interspecies differences in pharmacokinetics warrant specific investigation in these species. This study
involved investigation of the pharmacokinetics of tulathromycin in bison and white-tailed deer following a single 2.5 mg/kg bw subcutaneous injection (n=10) of Draxxin (Pfizer Inc.) to provide important information regarding tulathromycin dosage regimens in these species. As well, tulathromycin distribution and depletion in deer muscle and lung tissues following a 2.5 mg/kg bw subcutaneous injection of Draxxin was investigated to obtain pilot information regarding withdrawal time of tulathromycin in deer.
For the pharmacokinetic studies, serial blood samples were collected at baseline and up to 25 days post-injection. Pharmacokinetic parameters were estimated using non-compartmental methods. For the tissue pilot study, deer (n = 2 to 3) were slaughtered at 0, 1, 2, 6, 7, and 8 weeks post-injection. A quantitative analytical liquid chromatography-mass spectrometry method for measuring tulathromycin was developed and validated in bison and deer serum and deer lung and
muscle according to international guidelines. Samples were processed by solid-phase extraction. Reverse-phase chromatography was performed by gradient elution. Positive electrospray
ionization was used to detect the double charged ion [M+2H]+2 at m/z 403.9 and monitored in selected ion monitoring mode.
Tulathromycin demonstrated early maximal serum concentrations, extensive distribution, and slow elimination characteristics in deer and bison. In bison, mean Cmax (195 ng/mL) was lower compared to cattle (300 to 500 ng/mL) and half-life (214 hours) longer (cattle, 90 to 110 hours). In deer, mean Cmax (359 ng/mL) is comparable to cattle, but half-life (281 hours) was much longer. Tissue distribution and clinical efficacy studies are needed in bison to confirm extensive distribution of tulathromycin into lung and the appropriate dosage regimen. Tulathromycin was extensively distributed to deer lung and muscle, with tissue levels peaking within 7 to 14 days after injection. Drug tissue concentrations were detected 56 days after treatment, longer than the established withdrawal time of 44 days in cattle. This prolonged drug concentration in the tissue is supportive for the administration of tulathromycin as a single
injection therapy for treatment of respiratory disease of deer. While more study is needed to establish a recommended withdrawal time, the long serum and tissue drug half-life and extensive interindividual variability in tissue levels suggests a withdrawal period well beyond 56 days may be required in deer.
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A studio project in woodcarving : the symbolism of the buffalo in art yesterday, today, and tomorrowWise, Heather M. January 2001 (has links)
This creative project interpreted and applied the buffalo in Native American culture - its symbolism, significance and virtues - to woodcarvings for the lives of people today. The carvings explored a range of styles, media and symbols but all use buffalo imagery and each piece represents how I have applied the buffalo to my life. Some pieces are based on historical events while others explore personal emotions. Wood surfaces differ from natural or bleached to painted. No style unifies the body of work. In each piece realism and abstraction, positive and negative space is handled differently. Buffalo facts and myths were interpreted to convey what white people can learn from the buffalo. It was a spiritual link and messenger from Native Americans to the Great Spirit. The buffalo was revered and respected as a vital in the life cycle. White man destroyed the buffalo during the nineteenth century through the acts of greed, disrespect and ignorance. It seems to have returned with a message for people of all races. This message is one that must be found within each individual. / Department of Art
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From reformations to progressive reforms paradigmatic influences on wildlife policy in Yellowstone National Park /Turney, Elaine C. Prange. January 1900 (has links) (PDF)
Thesis (Ph. D.)--Texas Christian University, 2007. / Includes bibliographical references (leaves 258-279). Also available online as a PDF file.
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The impacts of wood bison (Bison bison athabascae) grazing on a sub-hygric shrub meadow plant community type, Mackenzie Bison Sanctuary, Northwest Territories /Smith, David L. January 1990 (has links) (PDF)
Thesis (M. Sc.)--University of Alberta, 1990. / Submitted to the Faculty of Graduate Studies and Research in partial fulfilment of the requirements for the degree of Master of Science, Department of Botany. Includes bibliographical references. Available also in electronic format on the Internet.
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Ecological hierarchy of foraging in a large herbivore: the plains bison perspective in tallgrass prairieRaynor, Edward James, IV January 1900 (has links)
Doctor of Philosophy / Division of Biology / John M. Briggs / Anthony Joern / Foraging decisions by native grazers in fire-dependent landscapes reflect fire-grazing interactions. I assessed behavioral responses associated with the attraction of grazers to recently burned areas at multiple spatial scales. (a) I focused on feeding in the area between steps in a foraging bout – the feeding station – where forage quality and vegetation architecture underlie these fine-scale decisions. The ‘forage maturation hypothesis’ (FMH) predicts the distribution of large herbivores based on the temporal dynamics of forage quality and quantity, but does not address herbivore responses to inter-patch variation caused by fire-induced increases of forage quality. The ‘transient maxima hypothesis’ (TMH) also predicts variable forage quality and quantity, but in response to intermittent disturbance from fire. I described the effects of variable spring burn history to bison foraging and their spatio-temporal distribution at Konza Prairie. Forage attributes met predictions of the TMH to explain how forage maturation affects foraging behavior across watersheds with varying burn frequency. At sites burned in the spring after several years without burning, intake rate increased with increasing vegetation biomass at a greater rate during the early growing season than during the transitional mid-summer period. This foraging behavior occurred in response to a non-equilibrial pulse of high quality resource that set the stage in the burned area, and was then retained by repeated grazing over the growing season. Thus, bison responded increased forage resource availability resulting from transient maxima in infrequently-burned watersheds burned that spring and they intensely used these areas until forage availability and forage regrowth was not possible. (b) At the patch scale, bison selected areas of low-to-moderate grass cover in which to feed and avoided areas of high forb cover in the growing season. During the dormant season, however, bison selected feeding-sites with uniformly high canopy cover in watersheds that were not burned. (c) At the landscape-scale, infrequently burned watersheds (compared to watersheds that were not burned) provided the strongest significant predictor of bison space use in all early growing- and transitional-season months. (d) The probability of habitat selection was driven by availability of high foliar, protein and low-to-intermediate herbaceous biomass throughout the growing season. These results explain the hierarchy of foraging by a dominant consumer in an experimental landscape by linking two prominent hypotheses, TMH-FMH, proposed to explain spatial variation in forage quality and quantity at local and landscape scales.
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Výukový nástroj pro barvené Petriho sítě / Educational Tool for Coloured Petri NetsNavrátil, Ondřej January 2013 (has links)
Coloured Petri nets (CPN) are an extension of a standard place-transition Petri nets (P/T PN). Every token and place have its type (and eventually a value) and various inscriptions can be inserted into the net. CPN excel with great readibility and expresivity. At the same time, they carry a well-defined formal basis, which eases its computer simulation and allows limited verification of certain attributes to be performed. Motivation for doing this project is the simple fact that currently only one public software tool is available for CPN creation and simulation - CPNTools developed on the Aarhus university. The program, however, is quite complicated and hard to handle for an unexperienced user. The goal is to research capabilities and properties of both CPNs and CPNTools and on this basis design and implement a didactic application with swift and intuitive interface that helps users without deeper theoretical insight to get a grasp of the problematics.
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Comparative Dating of a Bison-Bearing Late-Pleistocene Deposit, Térapa, Sonora, MexicoBright, Jordon, Kaufman, Darrell S., Forman, Steven L., McIntosh, William C., Mead, Jim I., Baez, Arturo 01 December 2010 (has links)
A recently discovered Bison-bearing fossil locality at Térapa, Sonora, Mexico, had previously been dated to 440 ± 130 ka using whole rock 40Ar/39Ar on a basalt flow that impounds the deposit. This age is considerably older than the accepted age of about 240-160 ka for the migration of Bison into greater North America. The Térapa deposit also contains a mixture of fossils from extralimital or extinct tropical animals and temperate animals. Constraining the age of the deposit is critical to interpret the paleontologic and paleoclimatologic implications of this unique Sonoran fossil locality. Three additional geochronological methods have been applied to this deposit (infrared stimulated luminescence (IRSL), amino acid racemization (AAR), and radiocarbon) and the data from the original 40Ar/39Ar age were revisited. The IRSL data suggest that the impounding basalt flow and the sediments that abut it were emplaced 43 ka ago and that the oldest sediments were deposited shortly after. Two radiocarbon ages suggest the fossiliferous sediments were emplaced by 42 ka. Effective diagenetic temperatures inferred from the AAR results, combined with AAR data from a similar-age deposit in southern Arizona, are in accordance with the 40-43 ka age estimates. For the AAR results to corroborate the 40Ar/39Ar age, the effective diagenetic temperature for the area would need to be approximately 3 °C, which is unrealistically low for northern Mexico. The new geochronological results suggest the Térapa deposit and fossils are 40-43 ka old. The anomalously old 40Ar/39Ar age for the impounding basalt is probably the result of low 40Ar* concentrations and inherited 40Ar.
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Fuel Performance Modeling of Reactivity-Initiated Accidents Using the BISON CodeFolsom, Charles Pearson 01 December 2017 (has links)
The Fukushima Daiichi nuclear accidents in 2011 sparked considerable interest in the U.S. to develop new nuclear fuel with enhanced accident tolerance. Throughout the development of these new fuel concepts they will be extensively modeled using specialized computer codes and experimentally tested for a variety of different postulated accident scenarios. One accident scenario of interest, reactivity-initiated accident, is a nuclear reactor event involving a sudden increase in fission rate that causes a rapid increase in reactor power and temperature of the fuel which can lead to the failure of the fuel rods and are lease of radioactive material. The focus of this work will be on the fuel performance modeling of reactivity-initiated accidents using the BISON code being developed at Idaho National Laboratory. The overall goal of this work is to provide the best possible modeling predictions for future experimental tests. Accurate predictive capability modeling using BISON is important for safe operation of these tests and provides a cheaper alternative to the expensive experiments.
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Persistence in a Changing World: Bison and Horse Dietary Niche, Body Size, and Relative Abundance in Late Pleistocene BeringiaKelly, Abigail 14 July 2022 (has links)
No description available.
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Finite element analysis of the mechanisms of impact mitigation inherent to the North American bison (Bison bison) skullPersons, Andrea Karen 13 December 2019 (has links)
North American bison (Bovidae: Bison bison) incur blunt impacts to the interparietal and frontal bones when they engage in head-to-head fights. To investigate the impact mitigation of these bones, a finite element analysis of the skull under loading conditions was performed. Based on anatomical and histological studies, the interparietal and frontal bones are both comprised of a combination of haversian and plexiform bone, and are both underlain by bony septa. Additionally, the interparietal bone is thicker than the frontal. Data regarding the mechanical properties of bison bone are scarce, but the results of a phylogenetic analysis infer that the material properties of the closely-related domestic cow bone are a suitable proxy for use in the FEA. Results of the FEA suggest that the thickness of the interparietal in conjunction with the bony septa may prevent focal stresses by helping to absorb and disperse the blunt impact energy about the skull.
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