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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.
51

A comparative study of the osteology and myology of the thoracic limb of the pocket gopher and kangaroo rat

Allen, Leland R. 01 December 1950 (has links)
The purpose of this study was to determine the morphological differences in the osteology and musculature of the thoracic limb of the pocket gopher and kangaroo rat. This was accomplished by first, collection of specimens, second, the preservation and preparation of bones and muscles tor study and illustration, third, sketching and photograph­ing the sketches, fourth, noting and recording origins and insertions as well as any differences in the modification of anatomy with relation to habitat requirements. These two closely related families, Geomyide and Heteromyidae, show great morphological differences. Comparative volumetric measurements show that the forelimb of the pocket gopher is approximately twice the size of the fore­limb of the kangaroo rat. Differences in the myology were found in relative length, thickness, shape, overall size, and in origin and insertion. Variations were also found in the osteology of the two forms. These differences were gen­eral outline, locations of the tuberosities for muscle attach­ment and in the length and placement of the various bone processes.
52

An Evaluation of Control on the Pocket Gopher, Thomomys Talpoides, on the Cache National Forest, Utah

Richens, Voit B. 01 May 1967 (has links)
The Monte Cristo area of the Cache National Forest has consistently supported a heavy pocket gopher infestation for many years. In 1957, and several succeeding years, infested range was treated with poisoned grain for pocket gopher control. Nearby range (also infested) was no t treated. Thus, gopher- control l ed range became available for comparative study, with period s of successive annual control of 1, 2, 3, 4, and 5 years. Within each of these areas (designated as treatments) were located two study s ites in 1961 and three in 1962. Within each study site were three sample areas, and just out side each study site were two trap blocks. Half-acre trap blocks were saturated with snap t raps for 3- consecutive days to give a 3-day population index ; this was converted to population per acre by treatments for use with regression analysis. Mound and cast counts, which have been widely used as indicators of there lative abundance of gophers were made on the 1-acre sample areas of ea ch treatment. Within these sample areas line -plot transects were used to obtain in format ion on perennial plant numbers and y i e ld, annual plant abundance, and "bulbed plant" abundance.
53

Genic Differentiation Between Two Chromosomal Races of Pocket Gophers, Geomys bursarius

Bohlin, Raymond G. 05 1900 (has links)
Genic data from two chromosomal races of Geomys bursarius from a contact zone in central Texas indicated that the two races possessed distinct gene pools which would define them as separate species. Data from proteins encoded from 21 loci in this study substantiated this hypothesis. A pattern of alternately fixed alleles at the ADH-l, MDH-2, LDH-l, and IDH-1 loci with no apparent gene flow in zones of contact strongly suggested that these two races should be designated as separate species. Levels of heterozygosity and high FST values indicate that genomic structuring within Geomys is most heavily influenced by high levels of inbreeding and low migration rates. Fossorial rodents were suggested to undergo speciation primarily through parapatric means.
54

Phylogenetic relationships of forest spiny pocket mice (Genus Heteromys) inferred from mitochondrial and nuclear markers with implications for species boundaries /

Gonzalez, Malinda Wallentine, January 2005 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Integrative Biology, 2005. / Includes bibliographical references (leaves 21-27).
55

Molecular systematics of Baird's pocket gopher (Geomys breviceps)

Bodine, Deanna Martinez 08 1900 (has links)
Baird's pocket gopher (Geomys breviceps) is found in eastern Texas, eastern Oklahoma, central and western Arkansas, and western Louisiana. The cytochrome-b gene was sequenced and analyzed for 16 pocket gophers from throughout the range of the species. Similar phylogenetic trees were obtained using maximum-parsimony, maximum-likelihood, neighbor-joining, and Bayesian analyses. Two major clades were formed with northern individuals belonging to clade I and southern individuals belonging to clade II. G. b. sagittalis was paraphyletic in relation to G. b. breviceps in all analyses. Based on inconsistencies between the taxonomic classification and systematic relationships within Baird's pocket gopher, a taxonomic restructuring appears warranted.
56

Experimental and Numerical Analysis of Flow and Pressure Fields Inside a Variable Depth Single Pocket Hydrostatic Bearing

Horvat, Frank Eugene 12 September 2008 (has links)
No description available.
57

ALGORITHM FOR STAIRCASE MACHINING OF NON-CONVEX POLYGONAL POCKETS WITH ISLANDS

RAMASWAMI, HEMANT January 2002 (has links)
No description available.
58

An evaluation of pocket-model, numerical readout breath alcohol testing instruments

Van Tassel, William Edward 15 November 2004 (has links)
Eight small-scale breath alcohol measurement devices were tested for accuracy, precision and the ability to not yield false positive and false negative readings. These pocket-sized breath testers (PMBTs), which provided numerical readout of BrAC to the 100th of a percent, were smaller than evidential and preliminary breath test instruments (EBTs and PBTs). The smallest devices were approximately the same size of a cigarette lighter. Designed to provide drinkers feedback about their individual alcohol levels, the PMBTs ranged in price from $40-100 USD. The devices were first tested under laboratory conditions with alcohol solution simulators providing the alcoholic samples. They were then tested with human drinkers, under controlled field conditions. Each device was tested at multiple alcohol levels. Two of the eight PMBTs failed to complete all levels of testing and were excluded from the study. All PMBTs demonstrated the ability to not yield false positive and false negative readings. No device met NHTSA performance criteria for accuracy (systematic error) in testing EBTs at every alcohol level tested. An interaction between PMBTs and the alcohol test levels was found. Thus, accuracy was found to be dependent upon the alcohol level at which the devices were tested. No device met NHTSA performance criteria for precision in testing EBTs at every alcohol level tested. Precision varied depending on the testing condition. There was less precision under controlled field conditions than under laboratory conditions. Five of the six PMBTs that completed the testing overestimated BrAC; only one device read below actual BrAC. Ramifications of the findings are discussed, regarding the overestimation and underestimation of BrAC and the possibility of manufacturers intentionally calibrating the devices to overestimate BrAC. Potential PMBT users are discussed and areas for future research are addressed.
59

Educational uses of PDAs (personal digital assistants): undergraduate student experiences

Song, Yanjie., 宋燕捷. January 2009 (has links)
published_or_final_version / Education / Doctoral / Doctor of Philosophy
60

Biochemical Genetics of the Pocket Gopher Genus Geomys, and its Phylogenetic Implications

Penney, Dan F. 12 1900 (has links)
Electrophoretic techniques were utilized for the demonstration of variation in 22 proteins from 24 natural populations of four species ( G. bursarius, G. pinetis, G. arenarius and G. personatus ) of the Geomys complex of pocket gophers. Of the 24 structural loci , 19 were considered to be polymorphic. Five of the six esterases contributed greatested to the polymorphism while non-esterase proteins generally showed low values. In the GeoMys complex of pocket gophers in this study,selection appeared to be the most important influence on genetic structure with some evidence of random drift in two of the four species. Populations of G. arenarius and G. personatus had the highest average interspecific genetic similarities to G. bursarius and . pinetis was the most divergent. Biochemical evidence supports the phylogeny of Geomys based on morphological and fossil data.

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