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Spatial and Temporal Influences of Water Quality on Zooplankton in Lake Texoma

Description: Seventy-one aquatic species including the copepodids and nauplii were identified from Lake Texoma from August 1996 to September 1997. Zooplankton community structure, abundance and spatial and temporal distributions were compared among five lake zones delineated a priori based on chloride concentration. The zones, in order of decreasing chloride concentration, are the Red River zone (RRZ), Red river Transition zone (RRTZ), Main Lake zone (MLZ), Washita River Transition zone (WRTZ) and Washita … more
Date: May 2000
Creator: Franks, Jessica L.
Item Type: Refine your search to only Thesis or Dissertation
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Effects of Daily Oral Injections of Quercetin on Implanted Colon-25 Tumor Growth in Balb-C Mice

Description: The effects of three oral dosages (0.4 mg, 0.8 mg, and 1.6 mg) of quercetin on Colon-25 tumors implanted in Balb-c mice were studied. The data in this study show that: (1) certain dosages of quercetin in alcohol solutions, reduces the weight, and size of implanted Colon-25 tumors in Balb-c mice, (2) these same dosages of quercetin all produce a profound neutrophilia combined with a significant lymphopenia at day 20 post-implantation, and (3) there was relatively little evidence of histological … more
Date: May 2000
Creator: Hayashi, Adam
Item Type: Refine your search to only Thesis or Dissertation
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Spatial Analysis of Atrazine in the Elm Fork Watershed

Description: This study assessed the water quality of the Elm Fork Watershed with regards to the herbicide Atrazine. Atrazine is a potential environmental endocrine disruptor and carcinogen. Overall, concentrations were lower than the four-quarter drinking water average of 3 µg/Lthe Maximum Contaminant Level set by the USEPA. However, three creek stations had four-quarter average concentrations greater than 3 µg/L, and virtually all samples exceeded the 0.1 µg/L standard set in Europe [1,2]. Statistically s… more
Date: May 2000
Creator: Ochandio, Mario Roberto
Item Type: Refine your search to only Thesis or Dissertation
open access

Mutation Rate Analysis of the Human Mitochondrial D-loop and its Implications for Forensic Identity Testing

Description: To further facilitate mitochondrial DNA (mtDNA) sequence analysis for human identity testing, a better understanding of its mutation rate is needed. Prior to the middle 1990's the mutation rate applied to a forensic or evolutionary analysis was determined by phylogenetic means, This method involved calculating genetic distances as determined by amino acid or DNA sequence variability within or between species. The mutation rate as determined by this method ranged from 0.025-0.26 nucleotide subst… more
Date: May 2000
Creator: Warren, Joseph E.
Item Type: Refine your search to only Thesis or Dissertation
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Analysis and Development of Post Secondary Curriculum on Sustainability

Description: This thesis examines existing curricula at colleges and universities about sustainability and uses results to develop an introductory post secondary course curriculum. The proposed course is organized around three major elements - - science, philosophy, and economics - - all integral to understanding sustainability. Materials needed to teach the proposed 3-semester hour course including syllabus, teaching modules, transparencies, handouts, and exams were developed. Suggestions on how to teach a… more
Date: May 2000
Creator: White, Miki Machell
Item Type: Refine your search to only Thesis or Dissertation
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Improved Fabrication and Quality Control of Substrate Integrated Microelectrode Arrays

Description: Spontaneously active monolayer neuronal networks cultured on photoetched multimicroelectrode plates (MMEPs) offer great potential for use in studying neuronal networks. However, there are many problems associated with frequent, long-term use of MMEPs. The major problems include (1) polysiloxane insulation deterioration and breakdown, (2) and loss of gold at the gold electroplated indium-tin oxide (ITO) electrodes. The objective of this investigation was to correct these major problems. Qual… more
Date: May 2000
Creator: Zim, Bret E.
Item Type: Refine your search to only Thesis or Dissertation
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Carbachol- and ACPD-Induced Phosphoinositide Responses in the Developing Rat Neocortex

Description: Signal transduction via the phosphoinositide (PI) second messenger system has key roles in the development and plasticity of the neocortex. The present study localized PI responses to individual cortical layers in slices of developing rat somatosensory cortex. The acetylcholine agonist carbachol and the glutamate agonist trans-1-amino-1,3-cyclopentanedicarboxylic acid (ACPD) were used to stimulate PI turnover. The PI responses were compared to the distribution of the corresponding PI-linked rec… more
Date: August 2000
Creator: Hartgraves, Morri D.
Item Type: Refine your search to only Thesis or Dissertation
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Assessing the Spatial and Temporal Distribution of MTBE and BTEX Compounds in Lake Lewisville, Texas February 1999 - February 2000

Description: The spatial and temporal distribution of Methyl Tertiary-Butyl Ether (MTBE) and BTEX (Benzene, Toluene, Ethylbenzene, Xylenes) compounds were assessed in a multipurpose reservoir, Lake Lewisville, Texas between February 1999 and February 2000. Concentrations of MTBE ranged from 0.0 - 16.7 mg/L. Levels of MTBE in the lake were related to watercraft. BTEX concentrations were never detected above 2.0 mg/L during the sampling period. Finished drinking water from Denton and the Upper Trinity Regio… more
Date: August 2000
Creator: Lee, Anne W.
Item Type: Refine your search to only Thesis or Dissertation
open access

Requirements for Cell-Free Cyanide Oxidation by Pseudomonas Fluorescens NCIMB 11764

Description: The involvement of cyanide oxygenase in the metabolism of pyruvate and a-ketoglutarate-cyanohydrin was investigated and shown to occur indirectly by the consumption of free cyanide arising from the cyanohydrins via chemical dissociation. Thus, free cyanide remains the substrate, for which the enzyme displays a remarkably high affinity (Kmapp,4 mM). A model for cyanide utilization is therefore envisioned in which the substrate is initially detoxified by complexation to an appropriate lig… more
Date: August 2000
Creator: Parab, Preeti
Item Type: Refine your search to only Thesis or Dissertation
open access

Influence of copper on resistance of Lumbricus terrestris to bacterial challenge

Description: Earthworms, Lumbricus terrestris, were challenged orally and intracoelomically with two bacterial species, Aeromonas hydrophila and Pseudomonas aeruginosa, and mortality rates were observed. Neither were found to be particularly pathogenic at injected doses of up to 108 bacteria per earthworm. The influence of Cu++ (as CuSO4) on the earthworm's response to bacterial challenge was investigated by exposing earthworms to sublethal levels of Cu++ prior to bacterial challenge. Exposure at subletha… more
Date: August 2000
Creator: Simmons, Carla Stull
Item Type: Refine your search to only Thesis or Dissertation
open access

The Adolescent Stress Response to a Naturalistic Driving Stressor

Description: The proposed study examined the role of anxiety and risk-taking in driving performance in adolescents. In addition to examining the sample as a whole, gender differences were assessed given earlier reports from our laboratory and others indicating that males and females differ with respect to risky behaviors to driving performance and anxiety. Adolescents' subjective and physiological responses to a driving simulator task were assessed. Anxiety was measured via self report and salivary cortisol… more
Date: August 2000
Creator: Wingo, Mary
Item Type: Refine your search to only Thesis or Dissertation
open access

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
Item Type: Refine your search to only Thesis or Dissertation
open access

The Effects of Electrochemical Therapy on Colon-25 Tumors in Balb-C Mice

Description: The purpose of the research was to treat immunodeficient mice, implanted with colon-25 tumors, with continuous and interrupted electrochemical therapy (ECT). ECT involves the placement of two electrodes, an anode near the center of the tumor and a cathode into the tumor periphery. A constant voltage is applied across the electrodes for a given period of time. The data showed that the interrupted and continuous ECT resulted in a decrease in mean tumor growth as compared to that of the sham contr… more
Date: December 2000
Creator: Gillen, Aric
Item Type: Refine your search to only Thesis or Dissertation
open access

Head Trauma Release of Histamine from Dural Mast Cells Alters Blood-Brain Barrier: Attenuation with Zolantidine

Description: This study employed a new model of mild-to-moderate head trauma to specifically identify the role of dural mast cell (MC) histamine in trauma-induced increased permeability in the blood-brain barrier (BBB). A single line was scored partially through the left dorsal parietal skull. Immediately following the trauma, degranulation was seen in 39% of the MCs on the left and in 2% on the right. After a 20 min survival period, left duras showed 55% with MC degranulation (fewer with complete degranula… more
Date: December 2000
Creator: Laufer, Susan R.
Item Type: Refine your search to only Thesis or Dissertation
open access

Establishment and Competitive Ability of Nelumbo Lutea in Relation to Myriophyllum Spicatum

Description: Limitations from reduced light and increasing water depth on Nelumbo lutea seedlings were determined in tank experiments. Survival was high in all tested light levels. Total biomass increased significantly with increasing light. Biomass allocation shifted significantly to root production between 3 and 6 weeks in the 10 and 24% levels. Survival decreased with increasing planting depth, and biomass of survivors reduced significantly between 0.5, 1.0, and 1.5 m depths. Nelumbo lutea and Myriophyl… more
Date: December 2000
Creator: Snow, Joe R.
Item Type: Refine your search to only Thesis or Dissertation
open access

Isolation and analysis of cotton genomic clones encompassing a fatty acid desaturase (FAD2) gene

Description: Polyunsaturated fatty acids are major structural components of plant chloroplast and endoplasmic reticulum membranes. Two fatty acid desaturases (designated FAD2 and FAD3) desaturate 75% of the fatty acids in the endoplasmic reticulum. The w -6 fatty acid desaturase (FAD2) may be responsible for cold acclimation response, since polyunsaturated phospholipids are important in helping maintain plant viability at lowered temperatures. To study regulation of FAD2 gene expression in cotton, a FAD2 g… more
Date: May 2001
Creator: Kongcharoensuntorn, Wisatre
Item Type: Refine your search to only Thesis or Dissertation
open access

Unique applications of cultured neuronal networks in pharmacology, toxicology, and basic neuroscience

Description: This dissertation research explored the capabilities of neuronal networks grown on substrate integrated microelectrode arrays in vitro with emphasis on utilizing such preparations in three specific application domains: pharmacology and drug development, biosensors and neurotoxicology, and the study of burst and synaptic mechanisms. Chapter 1 details the testing of seven novel AChE inhibitors, demonstrating that neuronal networks rapidly detect small molecular differences in closely related comp… more
Date: May 2001
Creator: Keefer, Edward W.
Item Type: Refine your search to only Thesis or Dissertation
open access

Evaluation of the Chlorophyll/Fluorescence Sensor of the YSI Multiprobe: Comparison to an Acetone Extraction Procedure

Description: The purpose of this study was to examine the suitability of the YSI model 6600 Environmental Monitoring System (multiprobe) for long term deployment at a site in Lewisville Lake, Texas. Specifically, agreement between a laboratory extraction procedure and the multiprobe chlorophyll/fluorescence readings was examined. Preliminary studies involved determining the best method for disrupting algal cells prior to analysis and examining the precision and linearity of the acetone extraction procedur… more
Date: May 2001
Creator: Lambert, Patricia
Item Type: Refine your search to only Thesis or Dissertation
open access

The Last Laugh: Selected Edwardian Punch Cartoons of Edward Linley Sambourne

Description: The illustrative work of Edward Linley Sambourne for Punch magazine during the period 1901-1910 addresses a myriad of political topics prevalent during the Edwardian period in British history. This thesis examines two of those topics - Women's Suffrage and Socialism - through their artistic treatment by one of Britain's most influential periodicals. Through a study of the historical context and iconography of selected cartoons-of-the-week, one is better equipped to understand and appreciate the… more
Date: May 2001
Creator: Larson, Alison
Item Type: Refine your search to only Thesis or Dissertation
open access

Selection and Use of Aquatic Vegetation by Migratory Waterfowl in North Central Texas

Description: Assessment of aquatic plant selection by waterfowl has been conducted during the winters of 1997-2000 on 49 0.2-0.79 ha research ponds in north central Texas. Ponds were categorized by dominant plant species into eight habitat types. Census with waterfowl species identification were performed to investigate impacts of aquatic vegetation and water depth on waterfowl. Eighteen waterfowl species were observed. Peak migration occurred in late December/early January. Mixed native ponds and mixed nat… more
Date: May 2001
Creator: Smith, JoEtta Kaye
Item Type: Refine your search to only Thesis or Dissertation
open access

Portrait of Your Stream: Development and Assessment of a Stream Ecology Program for Middle-School Student

Description: Portrait of Your Stream (POYS) is a stream ecology and student action program designed for use with middle-school students. The program is correlated with learning cycle pedagogical methods emphasizing student-centered lessons and activities in both classroom and outdoor settings. Implementation of a pilot program in the Fall semester of 1999 was used to collect formal and informal responses and data from students and teachers. Data included changes in student knowledge, skills and attitudes an… more
Date: May 2001
Creator: Swirczynski, Brenda J.
Item Type: Refine your search to only Thesis or Dissertation
open access

Age-Dependent Effects Of Chronic GABAA Receptor Blockade In Barrel Cortex

Description: GABAA receptor binding is transiently increased in rat whisker barrels during the second postnatal week, at a time when neurons in the developing rat cortex are vulnerable to excitotoxic effects. To test whether these GABAA receptors might serve to protect neurons from excessive excitatory input, polymer implants containing the GABAA receptor antagonist bicuculline were placed over barrel cortex for a 4-day period in young (postnatal days 8 - 12) and adult rats. In the cortex of young, but no… more
Date: May 2001
Creator: Gargan, Lynn
Item Type: Refine your search to only Thesis or Dissertation
open access

Correspondence Between Aquatic Ecoregions and the Distribution of Fish Communities of Eastern Oklahoma

Description: I assessed fish community data collected by the Oklahoma Conservation Commission from 82 minimally impaired wadeable reference streams in eastern Oklahoma to determine whether existing aquatic ecoregions provide the best framework for spatial classification for the development of biological assessment methods and biocriteria. I used indirect ordination and classification to identify groups of sites that support similar fish communities. Although correspondence was observed between fis… more
Date: May 2001
Creator: Howell, Charles E.
Item Type: Refine your search to only Thesis or Dissertation
open access

A Novel Mechanism for Site-Directed Mutagenesis of Large Catabolic Plasmids Using Natural Transformation

Description: Natural transformation is the process by which cells take up DNA from the surrounding medium under physiological conditions, altering the genotype in a heritable fashion. This occurs without chemical or physical treatment of the cells. Certain Acinetobacter strains exhibit a strong tendency to incorporate homologous DNA into their chromosomes by natural transformation. Transformation in Acinetobacter exhibits several unique properties that indicate this system's superiority as a model for tra… more
Date: August 2001
Creator: Williamson, Phillip C.
Item Type: Refine your search to only Thesis or Dissertation
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