UNT Theses and Dissertations - 194 Matching Results

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Utilization of Corridor Habitat by White-tailed Deer (Odocoileus virginianus) in Denton County, Texas

Description: White-tailed deer (Odocoileus virginianus) (N=15) movements were determined with use of radio telemetry techniques to determine the utilization of corridor habitat on the Lake Ray Roberts Greenbelt Corridor (RRGC) in north central Texas. Home ranges were calculated using three estimation types. Male white-tailed deer tend to have home ranges twice that of female home ranges. Seasonal home ranges were largest during spring (Feb. - April) and fall (Aug. - Oct.) seasons. Males had greater seasonal… more
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Date: May 2004
Creator: Bruce, Troy Kenneth
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Comparison of Bare Root vs. Potted Plants, Species Selection, and Caging Types for Restoration of a Prairie Wetland, and Quantitative Analysis and Descriptive Survey of Plant Communities and Associations at Lewisville Lake Environmental Learning Area (LLELA), Lewisville, TX

Description: Lewisville Lake Environmental Learning Area (LLELA) is an 809-hectare property in Denton County, TX. A study of the vegetation community identified 466 species in 104 families, with 25% of the species from only two families, Asteraceae and Poaceae. The property demonstrates the characteristics of an early successional community, dominated by weedy species. Prairie communities are dominated by Johnson grass and ragweed, with climax tall grass prairie communities only in areas that have been plan… more
Date: May 2007
Creator: Buckallew, Robin R.
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Biogeography of Montane Mammals on the Colorado Plateau and Adjacent Regions

Description: This study identifies the biogeographic factors that structure small mammal communities on mountains of the Colorado Plateau and adjacent regions. Forty six isolated ranges were characterized across a 5-state study area encompassing the Colorado Plateau, including the central high plateaus of Utah and the Basin and Range Province (i.e. the Great Basin and mountains of Arizona and New Mexico). Presence/absence data of 25 montane mammal species were used to explore the interactions between histor… more
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Date: May 2004
Creator: Carr, Carla B.
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Spatial and temporal patterns exhibited by select physicochemical and biological water quality parameters in Lake Texoma, Oklahoma and Texas.

Description: From August 1996 through September 1997 eleven fixed stations were sampled monthly in January, March , April , July, August, September, and November and fortnightly in May and June for the purposes of establishing baseline conditions present in Lake Texoma as related to U.S. Army Corps of Engineers chloride control activities in the upper Wichita River, Texas. Five reservoir zones were identified a priori using historical chloride concentration data and include the Red River Zone (RRZ), Red Riv… more
Date: August 2004
Creator: Clyde, Gerard A.
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Hindrance of the Myosin Power Stroke Posed by the Proximity to the Troponin Complex Identified Using a Novel LRET Fluorescent Nanocircuit

Description: A novel luminescence resonance energy transfer (LRET) nanocircuit assay involving a donor and two acceptors in tandem was developed to study the dynamic interaction of skeletal muscle contraction proteins. The donor transmits energy relayed to the acceptors distinguishing myosin subfragment-1 (S1) lever arm orientations. The last acceptor allows the detection of S1's bound near or in between troponin complexes on the thin filament. Additionally, calcium related changes between troponin T and my… more
Date: May 2007
Creator: Coffee Castro-Zena, Pilar G.
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Mouse cortical cholinergic neurons: Ontogeny of phenotypes in vivo and in vitro.

Description: The development of cholinergic neurons in mouse frontal cortex was studied both in vivo and in vitro by immunocytochemistry with an antibody to choline acetyltransferase (ChAT), the enzyme responsible for acetylcholine synthesis. While cortical cholinergic neurons have previously been characterized in rat cortex, up until very recently, intrinsic cortical cholinergic neurons were considered to be absent in mouse, and little is known about their development or phenotypic characteristics. The pr… more
Date: August 2005
Creator: Coiculescu, Olivia Elena
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Bioavailability and toxicity of 2,4,6-trinitrotoluene in sediment.

Description: TNT (2,4,6-trinitrotoluene) is a persistent contaminant at many military installations and poses a threat to aquatic ecosystems. Data from environmental fate and toxicity studies with TNT revealed that sediment toxicity test procedures required modification to accurately assess sediment TNT toxicity. Key modifications included aging TNT-spiked sediments 8-14 d, basing lethal dose on measured sediment concentrations of the molar sum of TNT and its main nitroaromatic (NA) transformation product… more
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Date: May 2004
Creator: Conder, Jason M.
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Bioaccumulation of Triclocarban, Triclosan, and Methyl-triclosan in a North Texas Wastewater Treatment Plant Receiving Stream and Effects of Triclosan on Algal Lipid Synthesis.

Description: Triclosan (TCS) and triclocarban (TCC), widely used antimicrobial agents found in numerous consumer products, are incompletely removed by wastewater treatment plant (WWTP) processing. Methyl-triclosan (M-TCS) is a more lipophilic metabolite of its parent compound, TCS. The focus of this study was to quantify bioaccumulation factors (BAFs) for TCS, M-TCS, and TCC in Pecan creek, the receiving stream for the City of Denton, Texas WWTP by using field samples mostly composed of the alga Cladophor… more
Date: August 2007
Creator: Coogan, Melinda Ann
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BioInformatics, Phylogenetics, and Aspartate Transcarbamoylase

Description: In this research, the necessity of understanding and using bioinformatics is demonstrated using the enzyme aspartate transcarbamoylase (ATCase) as the model enzyme. The first portion of this research focuses on the use of bioinformatics. A partial sequence of the pyrB gene found in Enterococcus faecalis was submitted to GenBank and was analyzed against the contiguous sequence from its own genome project. A BLAST (Basic Local Alignment Search Tool; Atschul, et al., 1990) was performed in or… more
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Date: August 2000
Creator: Cooke, Patrick Alan
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Hypoxic and hyperoxic incubation affects the ductus arteriosus in the developing chicken embryo (Gallus gallus).

Description: Developing chicken embryos have two ductus arteriosus (DA) that shunt blood away from the lungs and to the chorioallantoic membrane, the embryonic gas exchanger. In mammals, DA closure is stimulated by an increase in blood gas O2 that occurs as the animal begins to breathe with its lungs. The goal of this study was to determine the influence of O2 levels during incubation on the vascular reactivity and morphology of the O2-sensitive DA and to examine the effects of changing O2 levels during l… more
Date: December 2009
Creator: Copeland, Jennifer
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Function of the ENOD8 gene in nodules of Medicago truncatula.

Description: To elaborate on the function(s) of the ENOD8 gene in the nodules of M. truncatula, several different experimental approaches were used. A census of the ENOD8 genes was first completed indicating that only ENOD8.1 (nt10554-12564 of GenBank AF463407) is highly expressed in nodule tissues. A maltose binding protein-ENOD8 fusion protein was made with an E. coli recombinant system. A variety of biochemical assays were undertaken with the MBP-ENOD8 recombinant protein expressed in E. coli, which did … more
Date: December 2006
Creator: Coque, Laurent
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Temperature tolerances and predation susceptibilities of transgenic and wildtype zebra danios, Danio rerio.

Description: Both the upper and lower temperature tolerances of red fluorescent protein transgenic zebra danios and wildtype zebra danios, Danio rerio, were significantly different via two different methods; however, all differences are small (< 1°C) and probably not ecologically important. The U.S. geographic distributions of both transgenic and wildtype zebra danios will not be restricted by their upper thermal tolerances, but will be limited to the southern and western portions of the U.S. by their lowe… more
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Date: August 2005
Creator: Cortemeglia, Cheryl
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Assessing Outcomes of a Recycling Education and Service Program within an Elementary School

Description: During the spring 2004 a pilot school recycling program was implemented within Robert E. Lee Elementary. The primary goal of the program was to determine how recycling education in the school would affect curbside recycling rates within the surrounding community. The program was a cooperative effort between the University of North Texas, City of Denton Solid Waste Department and Keep Denton Beautiful. Throughout the first months of the study during the spring 2004, an increase in curbside rec… more
Date: August 2005
Creator: Cunningham-Scott, Carey Beth
Item Type: Refine your search to only Thesis or Dissertation
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Application of Cultured Neuronal Networks for Use as Biological Sensors in Water Toxicology and Lipid Signaling.

Description: This dissertation research explored the capabilities of neuronal networks grown on substrate integrated microelectrode arrays in vitro to be applied to toxicological research and lipid signaling. Chapter 1 details the effects of chlorine on neuronal network spontaneous electrical activity and pharmacological sensitivity. This study demonstrates that neuronal networks can maintain baseline spontaneous activity, and respond normally to pharmacological manipulations in the present of three times… more
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Date: August 2004
Creator: Dian, Emese Emöke
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Green Improvements: A Consumer's Guide to Environmentally and Economically Responsible Home Repairs and Improvements for the North Central Texas Region

Description: The Consumer's Guide is designed to help consumers by providing guidelines for the purchase of specific energy-efficient household appliances- water heaters, air conditioning and heating systems, windows, dishwashers, refrigerators, clothes washers, and dryers. This serves two major purposes: to decrease the environmental impact of those products and to save consumers money over the lifetime of the products. The seven major appliances covered in this work are things that consumers tend to purch… more
Date: August 2004
Creator: Dickason, Deborah
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Surface Water and Groundwater Hydrology of Borrow-Pit Wetlands and Surrounding Areas of the Lewisville Lake Environmental Learning Area, Lewisville, Texas

Description: The focus of this study was to characterize the surface water and groundwater hydrology of borrow-pit wetlands located within the borders of the Lewisville Lake Environmental Learning Area (LLELA), east of the Elm Fork of the Trinity River. The wetlands were excavated into alluvial deposits downstream of the Lewisville Lake Dam. Both surface water and groundwater contribute to the hydro-period of the borrow-pit wetlands. Nearby marshes exhibit characteristics of groundwater discharge. Salinity … more
Date: August 2004
Creator: Dodd-Williams, Lynde L.
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Bacterial Cyanide Assimilation: Pterin Cofactor and Enzymatic Requirements for Substrate Oxidation

Description: Utilization of cyanide as the sole nitrogen source by Pseudomonas fluorescens NCIMB 11764 (Pf11764) occurs via oxidative conversion to carbon dioxide and ammonia, the latter satisfying the nitrogen requirement. Substrate attack is initiated oxygenolytically by an enzyme referred to as cyanide oxygenase (CNO), which exhibits properties of a pterin-dependent hydroxylase. The pterin requirement for Pf11764 CNO was satisfied by supplying either the fully (tetrahydro) or partially (dihydro) reduced … more
Date: May 2004
Creator: Dolghih, Elena
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Modeling of Land Use Change Effects on Storm Water Quantity and Quality in the City of Carrollton and the North Texas Area

Description: Development and population are rapidly increasing in urbanizing areas of North Texas and so is the need to understand changes in storm water runoff flow and its contamination by nutrients, sediment, pesticides and other toxicants. This study contributes to this understanding and has two primary components: first, development of a graphical user interface for a geographic information system and storm water management database, and second, performing a two-scale hydrological modeling approach (th… more
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Date: December 2003
Creator: Duncan, Phillip Brent
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Gene Flow among Populations of the Mayfly Epeorus pleuralis (Banks 1910) (Ephemeroptera: Heptageniidae) in Three Adjacent Appalachian Headwater Streams

Description: Dispersal of aquatic insects is difficult to measure with traditional direct trapping methodologies. However, genetic markers are an ideal surrogate to indirectly infer dispersal and gene flow. For this research, a portion of the cytochrome oxidase I gene was used to evaluate gene flow and dispersal of Epeorus pleuralis located in the northern Appalachian headwater streams of the Allegheny, Genesee, and Susquehanna watersheds. A total of 536 basepairs from 16 individual insects were used for… more
Date: May 2006
Creator: Dunlap, Rebecca
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Morphological and Hematological Responses to Hypoxia During Development in the Japanese quail, Coturnix coturnix

Description: Hypoxic responses in quail development differ depending upon stage, duration and level of oxygen partial pressure of embryo. Incubation was switched to/from 110mmHg partial pressure (hypoxia), to/from 150mmHg (normoxia) during different stages in development, and control was incubated in normoxia throughout. Hatchability and embryo survival resulted in no hatchlings in continuous hypoxia. Responses to various hypoxic exposures throughout development resulted in recovery/repair of hypoxic damage… more
Date: May 2003
Creator: Elmonoufy, Nourhan
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Mitochondrial DNA Sequence Variation in Populations of the Nine-Banded Armadillo (Dasypus novemcinctus)

Description: Four populations of nine-banded armadillos, Dasypus novemcinctus, were investigated in the south-central United States in order to assess genetic variation in an isolated population (Electric Island, Lake Hamilton, Garland County, Arkansas); a semi-isolated population (Arkansas Post, Arkansas County, Arkansas), and two free ranging populations (southern Arkansas and central Texas). A 233 basepair sequence of the D-loop region of mitochondrial DNA was sequenced in individuals from each populatio… more
Date: August 2000
Creator: Elrod, Diana Adams
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Stream water quality corridor assessment and management using spatial analysis techniques: Introduction, evaluation, and implementation of the WQCM model.

Description: The rapid development of once-rural landscapes often produces detrimental effects on surface water quality entering local reservoirs through vulnerable stream channels. This study presents a methodology that incorporates geographic information systems (GIS) and remote sensing techniques for the creation of a stream corridor evaluation mechanism, coined the water quality corridor management (WQCM) model. Specifically, the study focuses on determining the viability of the WQCM model in assessing … more
Date: August 2007
Creator: English, April R.
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Cyanide Assimilation in Pseudomonas Fluorescens: Characterization of Cyanide Oxygenase as a Pterin-Dependent Multicomponent Enzyme Complex

Description: Cyanide utilization in Pseudomonas fluorescens NCIMB 11764 occurs via oxidative conversion to carbon dioxide and ammonia, the latter satisfying the nitrogen requirement. Substrate attack is initiated by an enzyme referred to as cyanide oxygenase (CNO), previously shown to require components in both high (H) (>30 kDa) and low (L) (<10 kDa) molecular weight cell fractions. In this study, tetrahydrobiopterin (H4biopterin) was identified as a cofactor in fraction L, thus making CNO appear as a pte… more
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Date: May 2004
Creator: Fernandez, Ruby
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Comparative biochemistry and genetic analysis of nucleoside hydrolase in Escherichia coli, Pseudomonas aeruginosa, and Pseudomonas fluorescens.

Description: The pyrimidine salvage enzyme, nucleoside hydrolase, is catalyzes the irreversible hydrolysis of nucleosides into the free nucleic acid base and D-ribose. Nucleoside hydrolases have varying degrees of specificity towards purine and pyrimidine nucleosides. In E. coli, three genes were found that encode homologues of several known nucleoside hydrolases in protozoa. All three genes (designated yaaF, yeiK, and ybeK) were amplified by PCR and cloned. Two of the gene products (yeiK and ybeK) encode … more
Date: December 2002
Creator: Fields, Christopher J.
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