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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Moderní implementace LALR(1) konstruktoru / A modern implementation of LALR(1) parser generator

Fišer, Karel January 2013 (has links)
The goal of this thesis is to design and implement a modern parser generator. The result is a program that reads description of some context-free LALR(1) grammar and semantic actions from an input file. To output files the program generates source codes in several target modern object-oriented programming languages for implementation of the syntax analyzer which, when parsing the language corresponding to the given grammar, executes the given semantic actions. Powered by TCPDF (www.tcpdf.org)
12

The utilization of genetic markers to resolve modern management issues in historic bison populations: implications for species conservation

Halbert, Natalie Dierschke 17 February 2005 (has links)
The saga of the American bison (Bison bison) is a well-known story of death, destruction, and greed circumvented by early conservationists. The foresight of 5 cattlemen and the Canadian and U.S. governments at the apex of the population bottleneck in the 1880s led to the eventual establishment of several federal bison populations, from which virtually all of the 300,000 extant bison are descended. A survey of 54 microsatellite loci spanning each autosomal and both sex chromosomes was used to compare levels of genetic variation among 10 of the 11 federal bison populations in the U.S. Although most populations contain moderate levels of genetic variation, the majority of genetic variation is contained within only 4 of the federal populations surveyed. The distribution and partitioning of genetic variation confirm historical records of founding lineages and transfers among populations. Previously published mitochondrial and nuclear markers were used to survey federal bison populations for evidence of domestic cattle introgression. While only 1 population was found to contain low levels of domestic cattle mitochondrial DNA, 7 of the 10 surveyed populations had detectable introgression of nuclear genes from domestic cattle. From this, 2 federal bison populations were identified that have both high levels of genetic variation and no evidence of introgression of domestic cattle genes. The data obtained from this study were used to examine consequences of past and present management practices in closed bison populations. In the case of the Texas State Bison Herd, observed chronic small population size, low levels of genetic variation, low natality rates, and high juvenile mortality rates combined with the results of population modeling indicate a high risk of extinction within the next 50 years unless new genetic variation is introduced into the herd. Alternatively, analysis of population substructure and nonrandom culling reveal the necessity for further investigation into the long-term effects of current management practices in the Yellowstone National Park bison population. This study illustrates that while bison may be considered a conservation success story, long-term survival of protected federal populations requires the development of effective genetic management strategies.
13

Who wants a buffalo? : South Dakota fenced herds and experiments in management, 1901-1952 /

Nesheim, David A. January 1900 (has links)
Thesis (M.A.) -- Northern Arizona University, 2004. / "December 2004." Includes bibliographical references (leaves 113-124) and abstract.
14

The biology and management of the bison of Wood Buffalo National Park

Fuller, William Albert, January 1957 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1957. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
15

The national movement to preserve the American buffalo in the United States and Canada between 1880 and 1920 /

Coder, George D. January 1975 (has links)
No description available.
16

The Effects of Bison on Cattle Winter Range in the Henry Mountains of South Central Utah: Resolving a Conflict

Ware, Ian M. 01 December 2012 (has links)
The American Bison in the Henry Mountains are one of the last free-roaming, genetically pure herds of bison remaining in North America. Over the last decade, the herd has used a cattle winter range during the summer and early fall, creating a conflict between the wildlife officials who manage the bison population, and BLM officials and local ranchers who manage the rangeland.
17

American Bison Ecology and Bison-Cattle Interactions in an Isolated Montane Environment

Ranglack, Dustin H. 01 May 2014 (has links)
As bison are considered to be ecologically extinct, and negative interactions between bison and cattle are perceived to limit bison restoration and cattle production, I designed a series of studies to test for potential competition between bison (Bison bison) and cattle (Bos taurus) for forage on the Henry Mountains in southern Utah. These studies provide insight into key information gaps previously identified by the Utah Division of Wildlife Resources (UDWR), Bureau of Land Management, and the local grazing association. The results indicate that bison and cattle are not strong competitors for forage on the Henry Mountains. Jackrabbits (Lepus californicus) emerged as the strongest competitive threat to cattle, consuming more than twice the amount of forage consumed by bison. Further, bison habitat preferences did not match with cattle habitat needs as reported by a survey of the local ranching community. This suggests that negative impacts on cattle due to bison have been overstated. Still, any potential negative impacts of bison will be felt by a small group of local individuals. This prompted me to design a new management scheme, which has the potential to increase the number of bison on the Henry Mountains while also compensating local ranchers for reducing the number of cattle they graze in the area. This system should be mutually beneficial for the local ranching community and the UDWR, and easily implemented by taking advantage of the currently exiting conservation license program.
18

An examination of species diversity and bison processing intensity contextualized within an aboriginal seasonality framework for late precontact sites on the Canadian northeastern plains

Playford, Tomasin 13 January 2015 (has links)
This dissertation considers faunal recoveries from a selection of archaeological sites located in the Canadian Northeastern Plains that date between AD 1000 and 1600. These faunal assemblages derive from three different archaeological cultures that are thought to reflect different subsistence orientations. The analysis quantifies this variability by assessing the taxonomic abundance and intensity of bone processing evident in the recoveries. At issue is determination whether variability in the faunal assemblage reflects differences in subsistence economy deriving from the diverse origins of these societies. This requires control over other potential contributors to variability. This includes ecological comparability of the site localities, consistency of excavation, sampling and analytic methods, and similarities in site function. Particularly important is determination that the selected sites reflect comparable seasons of site occupation. This latter consideration is important since the established archaeological and ethnological literature suggests that both available resources and the economic orientation of resident populations varied significantly with season. To this end, a major research component focused on the development of more refined means of determining the season of site occupation by measuring the degree of osteological development of recovered foetal bison bones. The creation of linear regression equations based on these measurements will allow applied archaeologists to establish season of site occupation without the need for a large, difficult to obtain foetal bison comparative collection. The analysis suggests the variability in the faunal assemblages occurs independently of site cultural affiliation, and might reflect economic activities conditioned by more finely divided seasonal divisions than is apparent with the conventional four-season model deriving from agrarian European societies. Aboriginal language markers, specifically moon-names, were used to identify significant biophysical and bison reproductive events. By placing the six sites within Aboriginal concepts of seasonality, animal food subsistence choices are better understood. These results have implications for the classification scheme archaeologists have used to define subsistence strategies.
19

Comparing the genetic diversity of late Pleistocene Bison with Modern Bison bison using ancient DNA techniques and the mitochondrial DNA control region

Douglas, Kory C. Baker, Lori E. Adams, Robert P. January 2006 (has links)
Thesis (M.S.)--Baylor University, 2006. / Includes bibliographical references (p. 58-64).
20

Evaluation of the effect of dietary forage and concentrate levels on the fatty acid profile of bison tissue

Turner, Tyler 04 January 2006
The effects of feeding strategy on subcutaneous, perirenal adipose tissue and ribeye (longissimus dorsi) muscle fatty acid profiles were evaluated from 60 bison (Bison bison) bulls from Western Canada. Treatments included Forage Fed (n=19); short term concentrate feeding, <90 Day (n=9); mixed forage and concentrate feeding, 50:50 Forage:Grain (n=20); and Feedlot Finishing (n=12), and were analyzed for interactions and main effects between treatment and tissue type. Saturated fatty acids were found in larger (P<0.05) proportions within perirenal tissue for all treatments. Polyunsaturated fatty acids were concentrated (P<0.05) in the intramuscular tissue. Polyunsaturated fatty acid content was greater (P<0.05) in Forage Fed and 50:50 Forage:Grain than in <90 Day or Feedlot Finishing treatments. The polyunsaturated to saturated fatty acid ratio was greatest (P<0.05) for Forage Fed followed by 50:50 Forage:Grain, with <90 Day and Feedlot Finishing treatments having the lowest ratio. Linoleic acid content within intramuscular tissue was greatest (P<0.05) in the 50:50 Forage:Grain followed by the <90 Day treatment, with the Forage Fed group being intermediate, and the Feedlot Finishing being the lowest (P<0.05). Subcutaneous tissue contained more (P<0.05) conjugated linoleic c-9, t-11 acid than did intramuscular tissue. The conjugated linoleic c-9, t-11 acid content of intramuscular tissue was greater (P<0.05) in the Forage Fed and <90 Day treatments than in the 50:50 Forage:Grain and Feedlot Finishing treatments. Alpha-linolenic acid content was greatest (P<0.05) in intramuscular tissue of Forage Fed bison than the other treatments. Total omega-3 fatty acid concentration was greater (P<0.05), in the intramuscular tissue of Forage Fed bison, followed by <90 Day and 50:50 Forage:Grain being similar (P>0.05) with Feedlot Finishing having the lowest (P<0.05) content. Eicosapentaenoic, docosapentaenoic, and docosahexaenoic acid were all found in the greatest (P<0.05) proportion in the Forage Fed, and least (P<0.05) in the Feedlot Finishing treatment. </p> <p>The total omega-6 and arachidonic fatty acid content of intramuscular tissue was greater (P<0.05) in the Forage Fed and 50:50 Forage:Grain than in the <90 Day or Feedlot Finishing treatments. The omega-6 to omega-3 fatty acid ratio was greatest (P<0.05) for the 50:50 Forage:Grain followed by <90 Day with Feedlot Finishing being intermediate, and Forage Fed bison having the lowest (P<0.05) ratio. </p><p>Feedlot bison were compared to beef (<i>Bos taurus</i>) steers (n=4) and sheep wethers (<i>Ovis aries</i>) (n=3). Sheep had lower (P<0.05) saturated fatty acid content than did bison or beef in intramuscular tissue. Polyunsaturated fatty acid content of intramuscular tissue was greater (P<0.05) in bison than in beef or sheep. The ratio of polyunsaturated to saturated fatty acids was greater (P<0.05) for bison than for beef or sheep. The omega-6 to omega-3 fatty acid ratio was lower (P<0.05) for the bison than the beef, while sheep were intermediate (P<0.05).</p><p>Forage Fed bison compared to forage fed sheep wethers (n=3) showed that the ratio of polyunsaturated to saturated fatty acids was greater (P<0.05) in bison than sheep. The ratio of omega-6 to omega-3 fatty acids was similar (P>0.05) for both species.</p><p>Forage Fed bison yielded the greatest proportion of beneficial fatty acids amongst the bison treatments. Comparison of species under feedlot and forage finishing systems indicated bison to have a more desirable fatty acid profile than did beef or sheep finished under their respective systems.

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