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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

Inquiry-based science for high school students: a forensic unit

Description: This project constitutes an instructional unit for honors biology that involves the use of science in the field of criminal investigation and forensics. Before beginning the unit, the learners should have mastered basic laboratory skills, including use of the microscope. They should also have an understanding of the basic structure and function of DNA and its role in heredity and protein synthesis. The standard time frame is 24 days with 70-minute periods, but can be easily adjusted to meet cla… more
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Date: August 2000
Creator: Apple, Kendra Kea
Item Type: Refine your search to only Thesis or Dissertation

Characterizing the Municipal Solid Waste Stream in Denton, Texas

Description: Forty-two commercially collected dumpsters from Denton’s Municipal Solid Waste Stream were emptied, sorted and weighed to characterize the material types and make preliminary recycling policy recommendations. The general composition of Denton’s solid waste stream was not significantly different from the composition of the nation’s solid waste stream. Fifty-eight percent of the observed waste stream was recyclable. Paper made up the largest portion of recyclable materials and the "grocery" sourc… more
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Date: August 2000
Creator: Brady, Patricia D.
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

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
Item Type: Refine your search to only Thesis or Dissertation

Adherence and Haemagglutination of Moraxella Catarrhalis.

Description: M. catarrhalis is a gram-negative diplococci frequently associated with infections of the upper respiratory tract. During the past decade, some preliminary studies have attempted to elucidate mechanisms of adherence and haemagglutination of M. catarrhalis. These studies have reported, in many cases, inconsistent results. There are two purposes of this research. First, identify mechanisms that may potentially be associated with the adherence and haemagglutination of M. catarrhalis. Second, sug… more
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Date: August 2000
Creator: Kosterman, Edward, III
Item Type: Refine your search to only Thesis or Dissertation

Life History and Case Building Behaviors of Phylloicus ornatus (Banks) (Trichoptera: Calamoceratidae) In Two Spring Fed Tributaries in the Central Edwards Plateau Bioregion of Texas

Description: The life history and case-making behaviors of Phylloicus ornatus from two springfed first order streams in the Edwards Plateau Bioregion of Texas were studied from January 1998 to November 1999. Field larval, pupal and adult samples and laboratory rearings indicated a multivoltine cycle. First instars differ from late instars in number of labral setae and in having a unique spur-like claw on each lateral hump. Larval development was asynchronous with second through fifth instars and pupae pres… more
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Date: August 2000
Creator: Norwood, James Christopher
Item Type: Refine your search to only Thesis or Dissertation

A Data Fusion Framework for Floodplain Analysis using GIS and Remotely Sensed Data

Description: Throughout history floods have been part of the human experience. They are recurring phenomena that form a necessary and enduring feature of all river basin and lowland coastal systems. In an average year, they benefit millions of people who depend on them. In the more developed countries, major floods can be the largest cause of economic losses from natural disasters, and are also a major cause of disaster-related deaths in the less developed countries. Flood disaster mitigation research was c… more
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Date: August 2000
Creator: Necsoiu, Dorel Marius
Item Type: Refine your search to only Thesis or Dissertation

Production and Characterization of a Novel Extracellular Polysaccharide Produced by Paenibacillus velaei, Sp. Nov

Description: Paenibacillus velaei, sp. nov. is a soil bacterium capable of producing an unusually large amount of exopolysaccharide (EPS). The EPS contains glucose, mannose, galactose and fucose in a molar ratio of 4:2:1:1. The molecular weight of the EPS is higher than 2x106. The viscosity of 1% EPS is 1300 cP when measured at a shear rate of 1 sec-1. Physiological parameters for optimal production of the EPS were studied and it was found that 1.4 g dry weight per 1 l of medium was produced when the bacter… more
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Date: August 2000
Creator: Sukplang, Patamaporn
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

Development of a Procedure to Evaluate Groundwater Quality and Potential Sources of Contamination in the East Texas Basin

Description: This study contributes a procedure, based on data analysis and geostatistical methods, to evaluate the distribution of chemical ratios and differentiate natural and anthropogenic contaminant sources of groundwater quality in the East Texas Basin. Four aquifers were studied, Sparta, Queen City, Carrizo and Wilcox. In this study, Carrizo- Wilcox is considered as one aquifer, and Sparta-Queen City as another. These aquifers were divided into depth categories, 0-150 feet for Sparta-Queen City and 3… more
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Date: May 2001
Creator: Alderman, John H.
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

Riparian Forest Width and the Avian Community in a Greenbelt Corridor Setting

Description: The forest avian community of the Ray Roberts Greenbelt (Denton Co., Texas) was characterized for two years using point count station sampling, from fall 1998 to summer 2000. Richness data for both breeding seasons were correlated with two-spatial metrics: width of the riparian forest and distance to the nearest edge. There were significant correlations between forest interior species richness and both spatial metrics, for both breeding seasons. Based on these data, a minimum riparian forest wi… more
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Date: May 2001
Creator: Hoffman, Karl W.
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

The Developmental Physiology of the Zebrafish: Influence of Environment and Cardiovascular Attributes

Description: Temperature effects on the development of the zebrafish embryos and larvae and adults were examined. It was found that the earlier in development a temperature change was performed on an embryo, the more significant the change in survival and/or subsequent development. Thus, viable temperature ranges for zebrafish widened significantly as development proceeded. Adults reared and bred at 25oC produced embryos that were significantly more successful at the lower range of rearing temperatures comp… more
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Date: August 2001
Creator: Bagatto, Brian
Item Type: Refine your search to only Thesis or Dissertation
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