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Mechanisms Of Carnitine-Mediated Modulation Of Aflatoxin B1-Dna Adduct Formation, Ayub Mohd Yatim

Doctoral Dissertations

The main purpose of this study was to investigate the possible mechanism(s) of L-carnitine-mediated modulation of AFB₁-DNA adducts formation. The first part of the study investigated the effect of increased doses of carnitine on AFB₁ binding to macromolecules, AFB₁ uptake, activity of glutathione S-transferase (GST), and total glutathione concentrations in freshly isolated hepatocytes. Carnitine dose was significantly correlated with the formation of AFB₁-DNA adduct ( r = -0.68;p = 0.0002 ), AFB₁-protein adduct (r = 0.58;p = 0.017), but not AFB₁-RNA adduct (r = 0.14;p = 0.604). …

The Factors Affecting The Transfer Of Training Based On The Opportunity To Perform Trained Tasks, David Arnold Blair

Doctoral Dissertations

The purpose of this study was to identify and define the factors that affect the transfer of newly learned skills to the job. One factor that has been shown to affect the transfer of training to the job is the extent to which the training participants are given the opportunity to perform trained tasks once they return to their jobs. The opportunity to perform was to consist of two dimensions: breadth and activity level.

Training participants from a government facility and their immediate supervisors (N = 74) responded to two different questionnaires which measured the three dimensions of the opportunity …

The Evaluation Of Two Types Of Multivariate Analyses Applied To Grassland Vegetation Data From A Reclaimed Coal Mine Area In Southeast Kansas, Usa, Karen Frances Yates

Electronic Theses & Dissertations

This study presents an analysis of the use of classification and ordination techniques for the detection of sub-communities at a reclaimed coal refuse dump and strip minded area in southeast Kansas. Cover values for 58 grass, forb, and woody species were estimated in 103 systematically positioned plots across the reclamation grassland using the modified Daubenmeyer cover scale. The data were submitted to an array of default and variant classification and ordination analysis programs in order to assess their ability to detect sub-communities. The classifications obtained from the analyses were mapped and analyzed for differences in species composition, diversity, and spatial …

Comparison Of Forest Stand Edges In Riparian And Mesic Habitats Along Watts Bar Reservoir Shoreline, Ruth Anne Hanahan

Masters Theses

Approximately fifty years ago, the landscape upslope from the natural, riverine position banks of the Tennessee River was inundated by the closing of Watts Bar Dam. On the currently forested shoreline, habitats within the direct influence of the reservoir pool are riparian. Those above that influence are mesic. The purpose of this research was to determine compositional and structural differences between edges of mature forest stands established in a riparian habitat and those established in a mesic habitat along Watts Bar Reservoir shoreline.

Thirty quadrats were placed on shoreline sites with mature, minimally-disturbed forest stands: 15 in a riparian habitat …

Using The Spot-Mapping Censusing Technique To Assess Changes In Breeding Bird Communities At Santa Ana National Wildlife Refuge, Alamo, Texas, 1940-1996, Alberto Cantu

Theses and Dissertations - UTB/UTPA

Results of breeding-bird censuses done by Davis in 1940 and by Gehlbach between 1973-1978 at Santa Ana National Wildlife, Alamo Texas, were compared to a 1995-1996 bird survey done in Gehlbach's study area. According to the Wilcoxon rank-sum test, bird densities in 1940 and 1995-1996 were similar, while 1973-1978 densities were lower. The 1995-1996 bird community was 76% similar to both the earlier studies. However, the communities studied in 1940 and 1973-1978 had only a 60% similarity. Negligible differences in bird densities and species composition were found between the 1995 and 1996 communities. Differences are attributed to changes in vegetation …

The Diet Of Oryzomys Palustris Based On Stomach Content Analysis, Shannon L. Wright

Biological Sciences Theses & Dissertations

Oryzomys palustris (Harlan) is unusual in that it is one of two carnivorous mammals in the Family Muridae in North America. A diet analysis of Oryzomys palustris. the marsh rice rat, was done based on stomach contents. This was accomplished by taking the animals from two study areas located on the Eastern Shore of Virginia. The animals were taken monthly for one year. Once caught, the animals were sacrificed and their stomach contents were identified to the lowest taxonomic level possible. This study showed that rice rats were omnivorous mammals, eating a variety of foods, including dicots, monocots, crabs, …

Brown-Headed Cowbird (Molothrus Ater) Range Expansion Into The Southeast: Effects On The Passerine Populations Using North American Breeding Bird Survey Data, Elizabeth Pruitt Henderson

Biological Sciences Theses & Dissertations

North American Breeding Bird Survey data that were collected from 1971-1992 in Virginia, North Carolina, south Carolina, Georgia, Florida, Alabama and Tennessee were used in this analysis of the impact of Brown-headed Cowbird range expansion on four warbler and four vireo host species.

Maps of mean cowbird abundances were produced using kriging for the periods 1971-1975, 1976-1980, 1981-1985, 1986-1990 and 1991-1992. These maps illustrated a complex invasion of the southeastern United States by Brown-headed Cowbird.

Linear regression analyses of host and cowbird abundances within physiographic strata, showed no species to be in decline or increasing in abundance over the entire …

Feeding Habits Of Juvenile Largemouth Bass Micropterus Salmoides (Lacepede), Thomas R. Goodwill

Honors Theses

The stomachs of 110 juvenile largemouth bass, Micropterus salmoides (Lacepede) were examined to learn the early feeding habits of bass in a brackish environment. Bass were found to have five primary food sources: Taphromysis bowmani, Cloeon sp., Gammarus mucronatus, Micropterus salmoides, and Lepidophthalmus louisianum. Three feeding trends were observed during the course of the study. First, bass seemed to display prey selection. Second, bass length increased as prey size increased. Third, the types of prey eaten by the bass changed as the bass increased in size.

A Comparison Of Secondary Successional Woody Vegetation In Two Revegetated Fields In South Texas And An Assessment Of Habitat Use By The Olive Sparrow, Arremonops Rufivirgatus, Patrick Grant Wright

Theses and Dissertations - UTB/UTPA

Aspects of plant species composition and structure of two revegetated fields in western Cameron County, Texas, were studied between 1992 and 1995. Avian habitat suitability was assessed using the Olive Sparrow, Arremonops rufivirgatus, as an indicator species. Total vegetation volume at the Longoria Wildlife Management Area (WMA), an area revegetated in 1961, was 0.745 $\rm m\sp3V/m\sp2$ and that of the Anacua WMA, revegetated in 1983-4, was 0.546 $\rm m\sp3V/m\sp2$ in 1992. Secondary woody species at the Longoria and Anacua WMA's had a Shannon's index of diversity of 0.619 and 0.264, respectively. Secondary woody vegetation at the Longoria WMA had a …

Second Growth Forest As Potential Marten Habitat In Western Newfoundland: An Examination Of Forest Habitat Structure And Microtine Abundance, Brian R. Sturtevant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The American marten (Martes americana) is associated with large tracts of relatively undisturbed, mature coniferous forests. I examined coarse woody debris (CWD) structure and small mammal abundance with respect to forest age and stem structure within second-growth forests, in comparison with old-growth stands in western Newfoundland. Results suggest that a critical change in marten habitat quality may occur at stand senescence, due to decreased tree competition, more complex subcanopy structure, and increased meadow vole (Microtus pennsylvanicus) abundance.

Analysis of stem structure within a chronosequence of 19 second-growth stands indicated high intertree competition, with dense canopy closure …

A Survey Of Employees Of The United States Department Of Agriculture's Animal Damage Control Program, Susan A. Schroeder

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined the attitudes of employees of the United States Department of Agriculture's Animal Damage Control (ADC) Program. This research examined ADC employees' attitudes about wildlife, the ADC program and ADC employment, wildlife damage management methods, euthanasia and the killing process, and the role of various public and private groups on ADC policy. This study also applied the theory of organizational capture to the ADC program to test its utility in explaining the attitudes and behaviors of employees. Results were based on a survey of ADC employees conducted in January 1995.

Survey responses were analyzed to explore associations between …

The Influence Of Forest Fragmentation And Landscape Pattern On American Martens And Their Prey, Christina D. Hargis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Habitat fragmentation occurs when large tracts of an orginal habitat are replaced by smaller patches of two or more habitat types, largely through human activities. I studied the behavior of six measures of landscape pattern that seemed appropriate for quantifying fragmentation, and used these measures to investigate the effects of forest fragmentation on American martens (Martes americana) and their prey. The measures I selected were edge density, contagion, mean nearest neighbor distance between patches, mean proximity index, perimeter-area fractal dimension, and mass fractal dimension. To test the behavior of these measures with a variety of landscape patterns, I …

Assessment Of Kokanee Salmon, Oncorhynchus Nerka, Genetic Stocks In Flaming Gorge Reservoir, Utah-Wyoming, Michael F. Canning

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I investigated the relative abundance, spatial distributions, return to the creel, and growth rates of two genetic stocks of kokanee salmon, Oncorhynchus nerka, in Flaming Gorge Reservoir, Utah-Wyoming. The two genetic stocks consist of fish from the two major spawning populations of kokanee in the reservoir. One population, Shore Spawners, spawns along the eastern shoreline of the Open Hills area of the reservoir. The other population, Sheep Creek, spawns in Sheep Creek, a tributary located in the Canyon area of the reservoir.

Mitochondrial DNA of kokanee from each population was analyzed to determine haplotype differences between stocks. These haplotype …

Ecological Amplitude And Invasion Of Diffuse Knapweed At Yakima Training Center, Washington, Donna Denise Wilcox

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Diffuse knapweed (Centaurea diffusa) is an introduced annual or short-lived perennial from Eurasia that has become a threat to native rangelands in the Pacific Northwest. Military training activities on the Yakima Training Center (YTC) increase the likelihood that knapweed will expand its range at YTC. This study, conducted in a major watershed at YTC, focused on: 1) how a variety of environmental variables influences knapweed distribution, 2) the use of Landsat Thematic Mapper (TM) imagery to map existing knapweed populations, and 3) the use of a logistic regression model and geographical information systems (GIS) to create a potential …

Habitat Selection And Movement Of A Stream-Resident Salmonid In A Regulated River And Tests Of Four Bioenergetic Optimization Models, Mark D. Bowen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A bioenergetics model was constructed for stream-resident drift-feeding salmonids. Model predictions of surplus power (energy available per unit time for growth and reproduction) were not statistically distinguishable from observations of surplus power in three laboratory studies. Of 40 experimental trials in these three studies, the model correctly predicted surplus power in 39 cases (p < 0.05).

I collected observations of rainbow trout (Oncorhynchus mykiss) focal velocity and physical habitat availability in the Green River of northeastern Utah, USA (1988-1990). In the winter of 1988, Flaming Gorge Dam generated hydropower and delivered an lJDStable discharge regime with a higher mean discharge …

The Effect Of Salinity Level Upon The Yield, Root Growth, And Water Extraction Of Contrasting Rooting Subpopulations Of Alfalfa (Medicago Sativa) Under Conditions Of Zero Leaching, Laura A. Vincent

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A major problem in irrigated agriculture in the Western U.S. is the gradual accumulation of salinity in the plant root zone. These nonuniformly saline soils contain increasing amounts of salinity with depth, and salt accumulation is accelerated in situations where leaching is minimized. Root growth and thus plant yield is limited in these soils due to decreased water uptake. We studied the root growth of two subpopulations of alfalfa differing in their ability to produce fibrous roots to determine if altering root morphology would increase plant yield and water extraction, in an irrigated saline soil.

Soil profiles for a control …

Mule Deer Highway Mortality In Northeastern Utah: An Analysis Of Population-Level Impacts And A New Mitigative System, Mark E. Lehnert

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rerouting highways to accommodate construction of the Jordanelle Reservoir in northeastern Utah caused a dramatic increase in vehicle collisions with mule deer (Odocoileus hemionus). I evaluated the effectiveness of a new system of highway crosswalk structures installed to reduce deer losses and preserve seasonal migrations. In addition, I constructed computer simulation models to investigate how highway mortality has impacted the Jordanelle deer population.

The crosswalk system restricted deer crossings to specific, well-marked areas along highways where motorists could anticipate them. Subsequent to installation, mortality declined 42.3% and 36.8% along a four-lane and two-lane highway, respectively. I was unable …

An Ecological History Of Tintic Valley, Juab County, Utah, Jeffrey A. Creque

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This work was a case study of historical ecological change in Tintic Valley, Juab County, Utah, an area historically impacted by mining and ranching activities common to much of the American West. The temporal framework for the study was approximately 120 years, the period of direct Euroamerican influence. In recognition of the ecological implications of cultural change, however, the impacts of prehistoric and protohistoric human activity on study area landscape patterns and processes were also explicitly addressed.

The study included a narrative description of historic land uses and ecological change in Tintic Valley, and examined the changes in landscape patterns …

Livestock As Seed Disseminators For Reseeding Degraded Rangelands: The Role Of Dung In Gap Formation And Plant Establishment, Brian S. Auman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Livestock (cattle and sheep) were examined as seed disseminators for reseeding degraded Intermountain rangelands. "Hycrest" crested wheatgrass [Agropyron desertorum (Fisch. ex Link) Schult. X A. cristatum (L.) Gaert.] seed was fed to yearling Holstein steers and Suffolk ewes. Dung was collected from each animal type and deposited on plots of high and low densities of an annual [cheatgrass (Bromus tectorum L.)] and perennial [squirreltail (Sitanion hystrix Nutt.)] grass species. The experiment evaluated the ability of the dung to suppress the resident vegetation, and the recruitment and establishment of Hycrest seedlings emerging from the dung.

Sheep dung had …

Recruitment Of Blue Crab, Callinectes Sapidus, Postlarvae To The Back-Barrier Lagoons Of Virginia's Eastern Shore, Robert D. Brumbaugh

OES Theses and Dissertations

Most research on the early life history of the blue crab, Callinectes sapidus, has been conducted in large partially stratified estuaries such as the Chesapeake Bay. In contrast, little is known about the recruitment dynamics or habitat requirements of blue crab postlarvae (megalopae) in shallow well-mixed lagoonal systems that make up a considerable part of the species' range. In Virginia's coastal lagoons, planktonic blue crab megalopae are most abundant at night on flooding tides, and are not abundant during the daytime or on ebbing tides. This appears to enhance retention within the lagoons, despite the short residence time of water …

Factors Affecting Nitrogen Fixation Rates In Termites (Isoptera: Rhinotermitidae: Reticulitermes) And Termite Nitrogen Contributions Of Forest Ecosystems, Anthony Duane Curtis

Biological Sciences Theses & Dissertations

Termites host symbiotic bacteria that fix atmospheric nitrogen, which makes termites important in the biogeochemical cycling of nitrogen in ecosystems. The objective of this study was to estimate annual nitrogen contributions by termites by examining seasonal rates of nitrogen fixation, seasonal abundance of different termite castes and their nitrogenase activity, the effects of dietary nitrogen on nitrogenase activity, and low oxygen and high carbon dioxide atmospheres on termite nitrogenase activity, and the accuracy of mark-recapture studies to estimate termite population size.

Termite nitrogen fixation rates were monitored monthly for 10 Reticulitermes Holmgren colonies from June, 1993, to December, 1995. Rates …

The Effects Of Environmental Variability On The Population Structure Of The Eastern Oyster (Crassostrea Virginica): A Modeling Study, Margaret Mcmanus Dekshenieks

OES Theses and Dissertations

Three models were coupled to investigate the effects of changes in environmental conditions on the population structure of the Eastern oyster, Crassostrea virginica. The first model, a time-dependent model of the oyster population as described in Powell et al. (1992) and Hofmann et al. (1992, 1995), tracks the distribution, development, spawning, and mortality of sessile oyster populations. The post-settlement model incorporates mortality through parasitism, predation, food depletion and extremes in environmental conditions. The post-settlement model supplies the initial abundance of larvae spawned into the water column, and in turn is the recipient of cohorts of spawn which survive through metamorphosis. …

Seasonal And Mesoscale Variability In The Distribution Of Antarctic Krill, Euphausia Superba, West Of The Antarctic Peninsula, Cathy Meyer Lascara

OES Theses and Dissertations

Observations collected between November 1991 and September 1993 during four multidisciplinary cruises were analyzed to provide a description of seasonal and mesoscale variability in the distribution and abundance of Antarctic krill, Euphausia superba, within continental shelf waters west of the Antarctic Peninsula and to investigate possible relationships between variability in krill distributions and variability in selected environmental parameters. Acoustic measurements of krill were made each season at designated locations to estimate the abundance of krill, in terms of vertically-integrated krill biomass and the number of aggregations, characterize the depth distribution of krill, and provide a quantitative description of the size, …

Comparison Of Sapling Community Structure In Created And Natural Forested Wetlands In Southeastern Virginia, Sharon Ann Haines

Biological Sciences Theses & Dissertations

Forested wetlands are being destroyed at a rapid rate. Wetlands are valuable for flood control, aquifer recharge, and for their role in denitrification and storage of global carbon. When wetlands are lost, their functions and value to humans are lost as well. One response to the continued development of wetlands has been the artificial creation of new wetlands. This study compared the species density, relative density, coverage and frequency of occurrence of the woody vegetation in two southeastern Virginia created wetlands with that in two reference wetlands, also in southeastern Virginia, to determine the structural similarity of their respective communities. …

A Study On The Life History And Seasonal Foraging Habits Of The Salamander Desmognathus Quadramaculatus Holbrook, In Wv, Glenn R. Mills

Theses, Dissertations and Capstones

A study was conducted on Desmognathus quadramaculatus in the northern periphery of its range with some aspects of its life history, surface density, and seasonal foraging habits. The results in this study are compared to studies done on D. quadramaculatus in the southern portion of its range. Female D. quadramaculatus have been found tending egg clutches from June to September in the southern portion of its range and data collected in this study shows that egg deposition also occurs during this period in the northern population. Female size (SVL) at which D. quadramaculatus reach sexual maturity ranged from 57.6- 77.5 …

Nitrogen Transformations In A Mitigated Wetland In The Green Bottom Wildlife Management Area, Mark Allen Fisher

Theses, Dissertations and Capstones

Soil nitrogen (N) dynamics have been shown to be quite sensitive to the soil hydrology. Creation of a mitigation freshwater wetland from an old field provided an opportunity to examine changes in N dynamics in terrestrial, aquatic (but formerly terrestrial), and transition (seasonally inundated) soils.

This thesis determined N availability using in situ incubations of soils taken from three distinct habitat conditions based on the degree of inundation following wetland creation: (1) old field (no inundation), (2) transition (seasonally inundated, initially beneath 10-20 cm of water), and (3) mitigation wetland (permanently inundated). Sample plots were located along five parallel transects …

Geographic Variation Of S̲O̲R̲E̲X̲ C̲I̲N̲E̲R̲E̲U̲S̲ In West Virginia, Lisa Jane Gatens

Theses, Dissertations and Capstones

The morphological and geographical diversity of Sorex cinereus is evident in West Virginia. In an attempt to identify patterns of morphological variation relative to age, sex, and geographic locality, and to clarify taxonomic status of the West Virginia soricids by defining diagnostic characters applicable to this area, a sample of 288 specimens representing three taxa were analyzed statistically. Standard external measurements were recorded, and a series of 12 cranial and dental characters were measured and recorded for each specimen. Morphological variation due to age was found in S. c. cinereus, but not in the smaller reference samples of S. …

An Analysis Of Habitat Utilization And Feeding Ecology Of Plethodon Richmondi And Plethodon Cinereus In Northern West Virginia, Peter A. Kramer

Theses, Dissertations and Capstones

Studies were conducted on the comparative microhabitat requirements and feeling habits of the ravine salamander, Plethodon richmondi and the redback salamander, P. cinereus in northern West Virginia. Plethodon richmondi had a mean SVL of 49.7 ± 7.1 mm and were significantly larger than P. cinereus which had a mean SVL of 37.2 ± 8.0 mm. Both species had biennial egg laying patterns and deposited eggs in late spring or early summer. Juvenile P. richmondi were not surface active except for the early spring and neonates did not become surface active until the ensuing spring; conversely, P. cinereus juveniles exhibited more …

Genetic Analysis Of Rhinichthys Atratulus (Pisces: Cyprinidae) In North Central West Virginia, Alan Harper Tennant

Theses, Dissertations and Capstones

The blacknose dace, Rhinichthys atratulus, is a cyprinid minnow common to shallow streams throughout North America. It has been shown to be sensitive to anthropogenic stress and a study of the genetic nature of R. atratulus populations may yield information about their habitats. In West Virginia, two subspecies of R. atratulus are present, R. a. atratulus and R. a. obtusus, which are separated by the Allegheny divide. In north central West Virginia, R. a. atratulus was observed in the Cheat River drainage, an area previously thought be within the range of R. a. obtusus. Fish of the R. a. atratulus …

Ecological Correlates Of Protein Polymorphisms In A Desert And Non-Desert Population Of Belonia Saturata (Odonata: Anisoptera), Melissa Jean Hamilton

Theses Digitization Project

Two populations of the Big Red Skimmer Dragonfly, Belonia saturata (Odonata: Amisoptera), were studied to determine the thoracic temperatures maintained during flight, the presence of polymorphic enzyme systems, and to determine the differences in activity of glycerol-3-phosphate dehydrogenase between a desert and non-desert population.