UNT Theses and Dissertations - 6 Matching Results

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Ephippia Production, Activation, and Use of Ex-Ephippio Neonates of Ceriodaphnia Dubia as Toxicity Test Organisms

Description: Ceriodaphnia dubia is widely used as a test organism in monitoring water quality. At the present time, cultures must be continuously maintained in the laboratory. In an attempt to avoid continuous culture and maintenance, the hatching of ephippial eggs of C. dubia would provide test organisms when needed. In order to determine the parameters required for maximum hatching, approximately ninety-four thousand ephippia were exposed to a variety of conditions ranging from light and temperature regim… more
Date: August 1992
Creator: Poage, Duane W.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Evaluation of Diet, Water, and Culture Size for Ceriodaphnia Dubia Laboratory Culturing

Description: Six reagent waters, eleven diets, and two culture sizes were evaluated for culturing C. dubia. Different filtration techniques were used to prepare the reagent waters. The eleven diets were comprised of two algae augmented with eight supplements. Reproduction and growth were assessed to discern differences among C. dubia raised in mass cultures and cultured in individual cups, during which, bacterial population densities, lipid, protein, and carbohydrate concentrations of the diets were measure… more
Date: December 1992
Creator: Allen, Jerry D. (Jerry Dee)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Investigation of Inhibitory Influences in Neuronal Monolayer Networks Cultured from Mouse Spinal Cord

Description: The effects of the inhibitory neurotransmitters gammaamino butyric acid (GABA) and glycine were characterized on spontaneous activity recorded from mouse spinal cord cultures. The GABA concentration which completely inhibited burst activity was chosen as a quantifiable measure of culture drug response and was used to 1) assess interculture and intraculture variability, 2) determine the influence of culture age and initial activity on GABA responses, and 3) compare the GABA responses between net… more
Date: August 1992
Creator: Jordan, Russell S. (Russell Stall)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Site Directed Mutagenesis Of Dienelactone Hydrolase

Description: The role of individual amino acid residues of the enzyme dienelactone hydrolase was investigated. Using the polymerase chain reaction (PCR), a 1.9 kbp clcD fragment was amplified and subcloned yielding a 821 bp BamHI to EcoRI clcD subclone in the plasmid pUC19. Site-specific mutants of dienelactone hydrolase were created using mismatched oligonucleotides to prime DNA synthesis. Specifically modified proteins from mutated clcD genes (Arg 81 to alanine, Tyr 85 to phenylalanine and Arg 206 to alan… more
Date: December 1992
Creator: Chen, Wei, 1965-
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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The Stress Protein Response of Pimephales promelas to Copper

Description: Organisms synthesize stress proteins in response to a variety of stressors. The 68/70-kDa proteins (synonymous to the 72/73-kDa proteins) have shown to be the most promising stress proteins, and have been proposed as a biomarker of general organismal stress. The 68/70-kDa proteins were used in an antigen/antibody based approach to determine the duration of the stress protein response of Pimephales promelas following an acute exposure to copper sulphate.
Date: May 1992
Creator: Covington, Sean M.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Structural Analysis of the Genes Encoding the Oxalocrotonate Branch of the Pseudomonas putida TOL Plasmid pDKI meta-cleavage Pathway and the Expression of the xy1G Gene Product in Escherichia coli

Description: Three overlapping DNA fragments from the lower operon of Pseudomonas putida TOL plasmid pDK1, covering the xy1IH genes and downstream flanking region, were cloned into pUC19. They include a 2.8 kbp XhoI fragment, a 2.7 kbp PstI fragment and a 2.0 kbp EcoRI-HindIII fragment. They were subjected to DNA sequence analysis. The xy1I (4-oxalocrotonate decarboxylase) and xy1H (4-oxalocrotonate tautomerase) genes were found to possess coding regions of 792 and 189 nucleotides, respectively. A possible … more
Date: December 1992
Creator: Luo, Xuebin
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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