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Space Use, Microhabitat and Macrohabitat Use of the Three-Toed Box Turtle (Terrapene carolina) in North Texas

Description: Box turtle (Terrapene carolina) populations are steadily declining due their unique natural history, effects of climate change, and anthropogenic land use change. There is a need for updated information on box turtle space and micro and macro-habitat use to inform conservation efforts. This study used VHF radiotelemetry and GPS data loggers to examine box turtle space and habitat use in North Texas. Box turtle home range sizes averaged 6.6ha (range = 0.79 - 18.08, n = 23), and males (n = 9) had… more
Date: December 2022
Creator: Joseph, Sara A.
Item Type: Refine your search to only Thesis or Dissertation

Removal of selected water disinfection byproducts, and MTBE in batch and continuous flow systems using alternative sorbents.

Description: A study was conducted to evaluate the sorption characteristics of six disinfection byproducts (DBPs) on four sorbents. To investigate sorption of volatile organic compounds (VOCs), specially designed experimental batch and continuous flow modules were developed. The investigated compounds included: chloroform, 1,2-dichloroethane (DCE), trichloroethylene (TCE), bromodichloromethane (BDCM), methyl tertiary butyl ether (MTBE), bromate and bromide ions. Sorbents used included light weight aggregate… more
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Date: December 2002
Creator: Kadry, Ahmed Y.
Item Type: Refine your search to only Thesis or Dissertation
open access

Microsatellite-based genetic profiling for the management of wild and captive flamingo populations.

Description: Flamingo species generate tremendous interest whether they are small captive groups or wild populations numbering in the thousands. Genetic pedigrees are invaluable for maintaining maximum genetic diversity in captive, as well as wild, populations. However, presently there is a general lack of genetic data for flamingo populations. Microsatellites are loci composed of 2-6 base pair tandem repeats, scattered throughout higher eukaryotic genomes, often exhibiting high levels of polymorphism an… more
Date: December 2005
Creator: Kapil, Richa
Item Type: Refine your search to only Thesis or Dissertation

Investigating the Molecular Framesworks of Phloem-Cap Fiber Development in Cotton (Gossypium hirsutum)

Description: The current study focuses on the vascular cambium and the reiterative formation of phloem fiber bundles in cotton stems. The role of the TDIF-PXY-WOX pathway was examined in regulating cambial activity and the differentiation of phloem fibers. A study was conducted to identify and characterize the cotton WOX family genes, focusing on WOX4 and WOX14, aiming to identify and analyze their phylogenetic relationships, tissue-specific expression profiles, functional roles, and metabolic consequences… more
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Date: December 2023
Creator: Kaur, Harmanpreet
Item Type: Refine your search to only Thesis or Dissertation
open access

Influence of stormwater drainage facilities on mosquito communities within the city of Denton, Texas.

Description: Weekly collections were conducted from May to December, 2007 (153 trap nights, total) in Denton, Texas, in and around large storm drains and overpass drainage facilities in residential and non-residential areas, using Centers for Disease Control (CDC) light traps and gravid traps. A total of 1964 mosquitoes were collected, representing 24 species within 6 genera: Aedes, Anopheles, Culiseta, Culex, Psorophora, and Uranotaenia. Culex was the most abundant genus, representing 75% of all mosquitoes… more
Date: December 2008
Creator: Kavanaugh, Michael David
Item Type: Refine your search to only Thesis or Dissertation
open access

An Assessment of Storm Water Toxicity from the Dallas/Fort Worth Metroplex and Denton, Texas

Description: With the advent of national storm water regulations, municipalities with populations greater than 100,000 are required to obtain National Pollutant Discharge Elimination System Permits (NPDES) for storm water discharges. In addition to the sampling required for the permit process, the City of Fort Worth contracted with the University of North Texas' Institute of Applied Sciences to conduct acute toxicity testing using Pimephales prcmelas and Ceriodaphnia dubia on storm water samples received fr… more
Date: August 1995
Creator: Keating, Paul Redmond
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

Medial Medulla Networks in Culture: a Multichannel Electrophysiologic and Pharmacological Study

Description: Spontaneously active primary cultures obtained from dissociated embryonic medial medulla tissue were grown on microelectrode arrays for investigating burst patterns and pharmacological responses of respiratory-related neurons. Multichannel burst rates and spike production were used as primary variables for analysis. Pacemaker-like neurons were identified by continued spiking under low Ca++/high Mg++conditions. The number of pacemakers increased with time under synaptic blocking medium. Sensitiv… more
Date: August 1998
Creator: Keefer, Edward W. (Edward Wesley)
Item Type: Refine your search to only Thesis or Dissertation
open access

Metabolism and Action of Polyunsaturated N-acylethanolamines in Arabidopsis thaliana Seedlings

Description: The lipoxygenase (LOX) pathway plays an important role in the oxidative metabolism of polyunsaturated N-acylethanolamines (PU-NAEs). The LOX pathway functions in conjugation with hydrolysis by fatty acid amide hydrolase (FAAH) and to produce oxidized NAEs during seed germination and early seedling development. When Arabidopsis seedlings were grown in low micromolar concentrations of lauroylethanolamide (NAE 12:0), growth retardation and elevated endogenous PU-NAE levels were observed due to the… more
Date: August 2015
Creator: Keereetaweep, Jantana
Item Type: Refine your search to only Thesis or Dissertation
open access

Density, Distribution and Habitat Requirements for the Ozark Pocket Gopher (Geomys Bursarius Ozarkensis)

Description: A new subspecies of the plains pocket gopher (Geomys bursarius ozarkensis), located in the Ozark Mountains of north central Arkansas, was recently described by Elrod et al. (2000). Current range for G. b. ozarkensis was established, habitat preference was assessed by analyzing soil samples, vegetation and distance to stream and potential pocket gopher habitat within the current range was identified. A census technique was used to estimate a total density of 3, 564 pocket gophers. Through automo… more
Date: May 2004
Creator: Kershen, Audrey Allbach
Item Type: Refine your search to only Thesis or Dissertation
open access

Manipulations of Sucrose/Proton Symporters and Proton-pumping Pyrophosphatase Lead to Enhanced Phloem Transport But Have Contrasting Effects on Plant Biomass

Description: Delivery of photoassimilate, mainly sucrose (Suc) from photoautotrophic source leaves provides the substrate for the growth and maintenance of sink tissues such as roots, storage tissues, flowers and fruits, juvenile organs, and seeds. Phloem loading is the energized process of accumulating solute in the sieve element/companion cell complex of source leaf phloem to generate the hydrostatic pressure that drives long-distance transport. In many plants this is catalyzed by Suc/Proton (H+) symporte… more
Date: May 2015
Creator: Khadilkar, Aswad S
Item Type: Refine your search to only Thesis or Dissertation
open access

Origin and Role of Factor Viia

Description: Factor VII, the initiator of the extrinsic coagulation cascade, circulates in human plasma mainly in its zymogen form, Factor VII and in small amounts in its activated form, Factor VIIa. However, the mechanism of initial generation of Factor VIIa is not known despite intensive research using currently available model systems. Earlier findings suggested serine proteases Factor VII activating protease, and hepsin play a role in activating Factor VII, however, it has remained controversial. In thi… more
Date: December 2013
Creator: Khandekar, Gauri
Item Type: Refine your search to only Thesis or Dissertation
open access

Hematocrit, hematocrit Regulation and its effect on oxygen consumption in the late stage chicken embryo (Gallus domesticus).

Description: Hematocrit and hematocrit regulation have the potential to affect developing embryos. To examine the ability of chicken embryos at day 15 to regulate hematocrit, they were subjected to either repeated saline injections (5% of total blood volume) or repeated blood removal (5% of total blood volume). Embryos showed an ability to maintain hematocrit (~20%) despite blood volume increases up to 115% of initial blood volume. Embryos were not able to maintain hematocrit in the face of dramatic blood v… more
Date: August 2004
Creator: Khorrami, Sheva
Item Type: Refine your search to only Thesis or Dissertation
open access

Evolutionary Genetics of Certain Mice of the Peromyscus boylii Species Group

Description: The genetic structure of 49 natural populations of four species (P. attwateri, P. boylii, P. pectoralis, and P. polius) of the Peromyscus boylii species group was analyzed through application of chromosomal and electrophoretic techniques. Chromosomal variation within and among populations of the boylii species group was analyzed from 178 specimens. Electrophoretic techniques were utilized for the demonstration of variation in enzymes and other proteins encoded by structural loci and applied to … more
Date: December 1973
Creator: Kilpatrick, Charles William
Item Type: Refine your search to only Thesis or Dissertation
open access

Multiple Activities of Aspartate Transcarbamoylase in Burkholderia cepacia: Requirement for an Active Dihydroorotase for Assembly into the Dodecameric Holoenzyme

Description: The aspartate transcarbamoylase (ATCase) was purified from Burkholderia cepacia 25416. In the course of purification, three different ATCase activities appeared namely dodecameric 550 kDa holoenzyme, and two trimeric ATCases of 140 kDa (consists of 47 kDa PyrB subunits) and 120 kDa (consists of 40 kDa PyrB subunits) each. The 120 kDa PyrB polypeptide arose by specific cleavage of the PyrB polypeptide between Ser74 and Val75 creating an active polypeptide short by 74 amino acids. Both the 40 and… more
Date: December 2010
Creator: Kim, Hyunju
Item Type: Refine your search to only Thesis or Dissertation
open access

Functional Characterization of Plant Fatty Acid Amide Hydrolases

Description: Fatty acid amide hydrolase (FAAH) terminates the endocannabinoid signaling pathway that regulates numerous neurobehavioral processes in animals by hydrolyzing a class of lipid mediators, N-acylethanolamines (NAEs). Recent identification of an Arabidopsis FAAH homologue (AtFAAH) and several studies, especially those using AtFAAH overexpressing and knock-out lines suggest that a FAAH-mediated pathway exists in plants for the metabolism of endogenous NAEs. Here, I provide evidence to support this … more
Date: December 2010
Creator: Kim, Sang-Chul
Item Type: Refine your search to only Thesis or Dissertation
open access

Purification and Characterization of Proteolytic Aspartate Transcarbamoylase (ATCase) from Burkholderia cepacia 25416 and Construction of a pyrB1 Knock-out Mutant

Description: Burkholderia cepacia is a common soil bacterium of significance in agriculture and bioremediation. B. cepacia is also an opportunistic pathogen of humans causing highly communicable pulmonary infections in cystic fibrosis and immunocompromized patients. The pyrB gene encoding ATCase was cloned and ATCase was purified by the glutathione S-transferase gene fusion system. The ATCase in B. cepacia has been previously classified as a class A enzyme by Bethell and Jones. ATCase activity gels show… more
Date: December 2004
Creator: Kim, Seongcheol
Item Type: Refine your search to only Thesis or Dissertation
open access

Genetic Characterization of Central and South American Populations of Scarlet Macaw (Ara macao)

Description: The wild populations of the Scarlet Macaw subspecies native to southern Mexico and Central America, A. m. cyanoptera, have been drastically reduced over the last half century and are now a major concern to local governments and conservation groups. Programs to rebuild these local populations using captive bred specimens must be careful to reintroduce the native A. m. cyanoptera, as opposed to the South American nominate subspecies (A. m. macao) or hybrids of the two subspecies. Molecular marker… more
Date: May 2016
Creator: Kim, Tracy Ann
Item Type: Refine your search to only Thesis or Dissertation
open access

Evaluation of the Developmental Effects and Bioaccumulation Potential of Triclosan and Triclocarban Using the South African Clawed Frog, Xenopus Laevis

Description: Triclosan (TCS) and triclocarban (TCC) are antimicrobials found in U.S. surface waters. This dissertation assessed the effects of TCS and TCC on early development and investigated their potential to bioaccumulate using Xenopus laevis as a model. The effects of TCS on metamorphosis were also investigated. For 0-week tadpoles, LC50 values for TCS and TCC were 0.87 mg/L and 4.22 mg/L, respectively, and both compounds caused a significant stunting of growth. For 4-week tadpoles, the LC50 values… more
Date: December 2010
Creator: King, Marie Kumsher
Item Type: Refine your search to only Thesis or Dissertation

Ceramide Biosynthesis and NEET Proteins Impact Development, Function, and Maintenance of the Caenorhabditis elegans Germline

Description: I used the C. elegans genetic model to examine the role of ceramide biosynthesis (sphingolipid pathway) and iron regulation and found that each process impacts germline development and function. Using a sphingolipid specific antibody mAb15B4, I found that sphingolipids are associated with germ granules (P granules) within C. elegans and zebrafish; thus, suggesting conservation of macromolecules associated with germ granules. Phenotype analysis of ceramide biosynthesis mutants in C. elegans reve… more
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Date: August 2019
Creator: King, Skylar Dawn
Item Type: Refine your search to only Thesis or Dissertation
open access

The Influence of Stream Regulation on Genic Differentiation and Thermal Tolerance in the Red Shiner, Notropis Lutrensis

Description: Genetic variation and thermal tolerance were surveyed for variation attributed to nonuniform selection pressures for five populations of the red shiner, Notropis lutrensis, collected from regulated and unregulated portions of a Texas river. Populations within 30 km of a hypolimnion-release dam that experience large thermal perturbations were found to have higher levels of heterozygosity, higher levels of polymorphism, significantly depressed levels of upper thermal tolerance endpoints, and grea… more
Date: December 1982
Creator: King, Timothy L. (Timothy Lee)
Item Type: Refine your search to only Thesis or Dissertation
open access

Stock and Species Identification of Selected Marine Fishes and Shellfishes Using Allozyme Analysis and Isoelectric Focusing: Implications for Texas Fisheries Management

Description: Allozyme frequencies and general protein patterns were surveyed among selected Texas marine fishes and shellfishes to illustrate the application of biochemical genetic techniques to stock and species identification in fisheries management.
Date: May 1992
Creator: King, Timothy L. (Timothy Lee)
Item Type: Refine your search to only Thesis or Dissertation
open access

Comparison and Genetic Analysis of Host Specificity in Cluster BD1 Bacteriophages infecting Streptomyces

Description: Bacteriophages are viruses that specifically infect bacteria. When a phage infects a bacterium, it attaches itself to the surface of the bacteria and injects its DNA into the intracellular space. The phage DNA hijacks the cellular machinery of the bacteria and forces it to produce phage proteins. Eventually, the bacteria cell bursts or lyses, releasing new phage. The bacteria act as a host for phage reproduction. The ability for a phage to infect multiple bacterial species is known as host rang… more
Date: May 2019
Creator: Klug, Hannah
Item Type: Refine your search to only Thesis or Dissertation
open access

The impact of climate and flooding on tree ring growth of Fraxinus pennsylvanica in north-central Texas.

Description: Tree cores of Fraxinus pennsylvanica were used in a dendrochronological analysis investigating the species' responses to climate and flooding. The objective was to develop a model that incorporates the effects of precipitation, temperature, and flooding on radial growth in this species in north-central Texas. The trees exhibited strong climatic signals. The study clearly shows that all three factors have significant impacts on tree ring growth both prior to and during growth; however, the natur… more
Date: December 2009
Creator: Komperod, Mari
Item Type: Refine your search to only Thesis or Dissertation
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