UNT Libraries - 152 Matching Results

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Search for Surrogate Marker(s) of Immunity Following Vaccination with Experimental Vaccine (Autoclaved Leishmania Major + Bacille Calmette-Guérin) in Human Volunteers

Description: Cutaneous leishmaniasis (CL) is usually a self-limiting lesion on the skin while visceral leishmaniasis is a progressive, systemic disease with high mortality even if treated. The problem associated with treatment and vector control justifies a search for an effective vaccine which seems to be the only practical means to control the disease. The aim of this study is to identify immunological surrogate marker(s) associated with protection against Leishmania infection. The results indicate that a… more
Date: December 1998
Creator: Mahmoodi, Majid
Item Type: Refine your search to only Thesis or Dissertation
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Biogeographic Relationships of Pocket Gophers (Geomys breviceps and Geomys bursarius) in the Southeastern Portion of Their Ranges

Description: This research utilized population genetic analyses (protein starch-gel electrophoresis and DNA sequencing of the cytochrome b mtDNA gene), host-parasite specificity (lice coevolution), remote sensing of satellite data, and geographic information systems (GIS) to characterize newly discovered populations of pocket gophers (genus: Geomys) in Arkansas. These populations are isolated and occur in seemingly unsuitable habitat in the Ozark Mountains of Arkansas. Analyses of electrophoretic and ectopa… more
Date: August 1998
Creator: Elrod, Douglas Allen
Item Type: Refine your search to only Thesis or Dissertation
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Contemporary Biology Curriculum for Non-majors

Description: The proposed biology curriculum for non-majors has one main objective, namely to improve scientific literacy among college students. The National Science Education Standards defines scientific literacy as "the knowledge and understanding of scientific concepts and processes required for personal decision making, participation in civic and cultural affairs, and economic productivity". The suggested strategies to accomplish this goal are to limit the number of topics covered, introduce relevant s… more
Date: August 1998
Creator: Smallwood, Susan
Item Type: Refine your search to only Thesis or Dissertation
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Documentation of Biodiversity Impacts (Including Cumulative Biodiversity Impacts) in Environmental Impact Statements

Description: In the United States, biodiversity impact assessment has historically received little attention. Responding in 1993, the Council on Environmental Quality (CEQ) released guidelines on incorporating biodiversity into environmental impact assessment under the National Environmental Policy Act of 1969. The objectives of the study here were to identify the level of documentation of biodiversity impact assessment in sample Environmental Impact Statements (EISs); identify whether in the years followin… more
Date: August 1998
Creator: Bhatia, Sarika
Item Type: Refine your search to only Thesis or Dissertation
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Evaluation of Sequential Events in Phagocytosis by Earthworm Coelomocytes as Potential Immunotoxicity Biomarkers

Description: This research evaluated the potential of activation and attachment, as sequential companion biomarkers of phagocytosis by earthworm, Lumbricus terrestris, immunoactive coelomocytes for use in immunotoxicology. The potential was assessed by exposing earthworms to sublethal concentrations of CuSO4 and Arochlor 1254®, chemicals used as reference or standard immunotoxicants.
Date: August 1998
Creator: Murray, Stephanie Mae
Item Type: Refine your search to only Thesis or Dissertation
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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
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Nutrient Effects on Autofragmentation of Myriophyllum Spicatum L.

Description: A 2 x 2 factorial design investigated effects of sediment nitrogen and water potassium levels on autofragment production. Reduced nitrogen levels significantly increased autofragment production whereas potassium levels did not significantly alter production. Up to 50% of autofragment production abscised from parent plants grown under low nitrogen conditions compared to 12% or less under high nitrogen conditions.
Date: August 1998
Creator: Smith, Dian H. (Dian Helen)
Item Type: Refine your search to only Thesis or Dissertation
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Oral Microbiology

Description: Recent studies regarding research on oral microorganisms and the oral diseases are presented. The normal flora of the mouth and the oral environment are first described. Dental plaque and dental caries are primary causes of oral disease. Streptococcus mutans is the major contributor in the initiation and progression of dental caries. Lactobacillus, Actinomyces, and Veillonella are other genera of bacteria linked to dental caries. Periodontitis and gingivitis are periodontal diseases that are ca… more
Date: August 1998
Creator: Osman, Shaiesta
Item Type: Refine your search to only Thesis or Dissertation
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Physical and Functional Characterization of the xy1XYZ Region From TOL Plasmid pDK1 and its Associated Downstream Regulatory Elements

Description: The nucleotide sequence for the pDKl TOL plasmid region encoding toluate-1,2-dioxygenase (Xy1XYZ, TO) was determined. TO is the first enzyme in the meta-cleavage operon, responsible for the conversion of toluates and benzoates to their carboxy-substituted diols. DNA sequence analysis revealed the presence of three open reading frames (ORF). The three ORFs correspond to xylX (1353 bp), xylY (486 bp) and xylZ (1008 bp), encoding predicted protein products of 51370 Da, 19368 Da and 36256 Da, respe… more
Date: August 1998
Creator: Hares, Douglas R. (Douglas Ryan)
Item Type: Refine your search to only Thesis or Dissertation
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Underwater Optical Properties of Lake Texoma (Oklahoma-Texas) Using Secchi Disk, Submarine Photometer, and High-Resolution Spectroscopy

Description: The underwater optical climate of Lake Texoma was measured at eleven fixed stations from August 1996 to August 1997. Secchi transparency and submarine photometry characterized seasonal and spatial values of secchi depth (SD), vertical attenuation coefficient (η''), and depth of euphotic zone (Zeu). Indices of Zeu:SD and η'' × SD were compared with universally applied values derived from inland and coastal waters. Turbidity explained 76% of the variation (p = 0.0001) of η'' among water quality p… more
Date: August 1998
Creator: Rolbiecki, David A. (David Alan)
Item Type: Refine your search to only Thesis or Dissertation
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Use of tRNA Gene Probes to Identify Polymorphic Loci in the Bovine Genome

Description: A 30-mer oligonucleotide probe encoding the "A box" and anticodon loop regions of a human glycine tRNA gene was used to isolate a 581bp DNA fragment from a bovine genomic DNA library. Although the cross-hybridizing segment of DNA was found not to encode any tRNA gene or pseudogene, a region with homology to the "C-element" of the "BOV-tA" type Alulike artiodactyl retroposons was identified. This cross-hybridization was determined to be the result of conserved RNA polymerase III promoter element… more
Date: August 1998
Creator: Shariat, Parvaneh
Item Type: Refine your search to only Thesis or Dissertation
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Analysis of the Trypanosoma brucei Genome and Identification and Characterization of a Gene Family Encoding Putative EF-Hand Calcium-Binding Proteins

Description: The flagellum of Trypanosoma brucei contains a family of antigenically related EF-hand calcium-binding proteins which are called the calflagins. Genomic Southern blots indicated that multiple copies of calflagin genes occur in T brucei. All of the copies were contained in a single 23 kb Xhol-Xhol fragment. Genomic fragments of 2.5 and 1.7 kb were cloned that encoded calflagin sequences. Two new members of the calflagin family were found from genomic clone sequences. The deduced amino acid seque… more
Date: May 1998
Creator: DeFord, James H. (James Henry), 1956-
Item Type: Refine your search to only Thesis or Dissertation
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A Behavioral Model for Detection of Acute Stress in Bivalves

Description: A behavioral model for acute responses in bivalves, was developed using time series analysis for use in a real-time biomonitoring unit. Stressed bivalves closed their shell and waited for the stressful conditions to pass. Baseline data showed that group behavior of fifteen bivalves was periodic, however, individuals behaved independently. Group behavior did not change over a period of 20 minutes more than 30 percent, however, following toxic exposures the group behavior changed by more than 30 … more
Date: May 1998
Creator: Allen, H. Joel
Item Type: Refine your search to only Thesis or Dissertation
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Biochemical Identification of Molecular Components Required for Cyanide Assimilation in Pseudomonas fluorescens NCIMB 11764

Description: Utilization of cyanide as a nutritional nitrogen source in P. fluorescens NCIMB 11764 was shown to involve a novel metabolic mechanism involving nonenzymatic neutralization outside of cells prior to further enzymatic oxidation within. Several cyanide degrading enzymes were produced by NCIMB 11764 in response to growth or exposure to cyanide, but only one of these cyanide, oxygenase (CNO), was shown to be physiologically required for assimilation of cyanide as a growth substrate.
Date: May 1998
Creator: Chen, Jui-Lin
Item Type: Refine your search to only Thesis or Dissertation
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Characterization of Aspartate Transcarbamoylase and Dihydroorotase in Moraxella Catarrhalis

Description: Bacterial aspartate transcarbamoylases (ATCase's) are divided into three classes that correspond to taxonomic relationships within the bacteria. The opportunistic pathogen Moraxeila catarrhalis has undergone several reclassifications based on traditional microbiological criteria. The previously uncharacterized ATCase from M. catarrhalis was purified to homogeneity and its chemical properties characterized. The ATCase from M. catarrhalis is a class C ATCase with an apparent molecular mass of 480… more
Date: May 1998
Creator: Fowler, Michael A. (Michael Allen), 1961-
Item Type: Refine your search to only Thesis or Dissertation
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Conception and Design of Constructed Wetland Systems to Treat Wastewater at the Biosphere 2 Center with Use of Reaction Rate Models and the Habitat Evaluation Procedure to Determine the Effects of Designing for Wildlife Habitat on Treatment Efficiency

Description: A study was undertaken to explore relationships between wetland characteristics which make them efficient water purifiers versus their ability to serve as wildlife habitat. The effects of designing constructed wetlands for improved habitat on water treatment efficiencies were quantified. Results indicate that some sacrifice in treatment efficiency is required and that the degree of efficiency reduction is dependant upon pollutant loading rates. However, sacrifice in efficiency is much smaller t… more
Date: May 1998
Creator: Clingenpeel, Glenn C. (Glenn Christopher)
Item Type: Refine your search to only Thesis or Dissertation
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Forensic DNA Extraction Strategies for PCR Analysis

Description: There is a transition nationwide on the analysis of forensic evidentiary stains containing biological material from traditional serology to Polymerase Chain Reaction (PCR) methodologies. The increased sensitivity of PCR, the limited number of alleles at each locus, and the necessity of producing unambiguous data for entry into the FBI's Combined DNA Index System make this study of extraction procedures of utmost importance. A "single tube" extraction procedure for blood stains collected onto FT… more
Date: May 1998
Creator: Van Winkle, Carolyn
Item Type: Refine your search to only Thesis or Dissertation
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Identification and Characterization of the Pyrimidine Biosynthetic Operon in Streptomyces griseus

Description: To further understand the ATCase/DHOase bifunctional complex formed in Streptomyces, the genes encoding these and other pyrimidine enzymes were identified and characterized. Polymerase chain reaction (PCR) was utilized in this effort. Primers were constructed by selecting conserved regions of pyrimidine genes from known gene and protein sequences of a wide variety of organisms. These sequences were then optimized to Streptomyces codon usage. PCR products were obtained from internal sites within… more
Date: May 1998
Creator: Hooten, Jody J. (Jody Jeran)
Item Type: Refine your search to only Thesis or Dissertation
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Responses of Cultured Neuronal Networks to the Cannabinoid Mimetic Anandamide

Description: The effects of cannabinoid agonists on spontaneous neuronal network activity were characterized in murine spinal cord and auditory cortical cultures with multichannel extracellular recording using photoetched electrode arrays. Different cultures responded reproducibly with global decreases of spiking and bursting to anandamide and methanandamide, but each agonist showed unique minor effects on network activity. The two tissues responded in a tissue-specific manner. Spontaneous activity in spina… more
Date: May 1998
Creator: Morefield, Samantha I. (Samantha Irene)
Item Type: Refine your search to only Thesis or Dissertation
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Biology and Energetics of Tropisternus Lateralis Nimbatus (SAY) (Coleoptera: Hydrophilidae) in a Playa on the Southern High Plains of Texas and Aquatic Coleoptera Diversity from Seven Playas on the Southern High Plains of Texas

Description: A study of the biology of Tropisternus lateralis, a hydrophilid beetle, was conducted during the flood period of a single playa on the Southern High Plains of Texas from early June 1995 through early September 1995. Mechanism of colonization, tolerance/avoidance to drought, larval density, and secondary production were analyzed. T. lateralis colonized playas from surrounding aquatic habitats and avoided drought through aerial dispersion. Once in the playa, larval density increased over time. Se… more
Date: December 1997
Creator: Cook, Robert E. (Robert Edward), 1969-
Item Type: Refine your search to only Thesis or Dissertation
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Distribution of a Novel Gram Negative, Capsule-Forming Bacterium

Description: A novel Gram negative, capsule-forming bacterium was previously isolated in Dr. G. Roland Vela's laboratory. The distribution of this bacterium in soils from various locations was investigated. Soil samples from 188 locations around the world were examined. Isolates of the bacterium were obtained from 50 of these soils, with 48 of the isolates found in soils from the southwestern United States and northern Mexico. This suggests that this region is the natural habitat of the bacterium. The other… more
Date: December 1997
Creator: Hughes, Roxana Bejarano
Item Type: Refine your search to only Thesis or Dissertation
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Evaluation of the Use of the Bivalves Ischadium recurvum Rafinesque, 1820 and Corbicula fluminea Muller, 1774 as Biological Indicators of Relative Water Quality in Terms of Growth and Upper Temperature Tolerance

Description: Growth of mussels under laboratory conditions was examined under various food regimes in different water types and temperatures. Growth was less than would be useful as an indicator and comparisons with field exposures were of minimal value. The effects of organophosphates on bivalves were examined via toxicity tests, tissue concentration, and by controlling exposure through the use of physical constraints. Upper temperature tolerance of both bivalve species was examined with respect to differe… more
Date: December 1997
Creator: Hemming, Jon Michael
Item Type: Refine your search to only Thesis or Dissertation
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Life History of Mayatrichia ponta Ross (Trichoptera: Hydroptilidae) in Honey Creek, Turner Falls Park, Oklahoma

Description: The life history and ontogenetic microhabitat change of Mayatrichia ponta Ross were investigated in Honey Creek, Turner Falls Park, Murray Co., Oklahoma, U.S.A. from August 1994 to August 1995. The shape of larval cases changed from a small cone to a cylinder. M. ponta had an asynchronous multivoltine life history with considerable cohort and generation overlap; five generations were estimated. The development rate was reduced in winter. The winter generations of M. ponta had wider head capsule… more
Date: December 1997
Creator: Wang, Yi-Kuang
Item Type: Refine your search to only Thesis or Dissertation
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