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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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Isolation and Characterization of the Operon Containing Aspartate Transcarbamoylase and Dihydroorotase from Pseudomonas aeruginosa

Description: The Pseudomonas aeruginosa ATCase was cloned and sequenced to determine the correct size, subunit composition and architecture of this pivotal enzyme in pyrimidine biosynthesis. During the course of this work, it was determined that the ATCase of Pseudomonas was not 360,000 Da but rather present in a complex of 484,000 Da consisting of two different polypeptides (36,000 Da and 44,000 Da) with an architecture similar to that of E. coli ATCase, 2(C3):3(r2). However, there was no regulatory polype… more
Date: May 1993
Creator: Vickrey, John F. (John Fredrick), 1959-
Item Type: Refine your search to only Thesis or Dissertation
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Cottonseed Microsomal N-Acylphosphatidylethanolamine Synthase: Identification, Purification and Biochemical Characterization of a Unique Acyltransferase

Description: N-Acylphosphatidylethanoiamine (NAPE) is synthesized in the microsomes of cotton seedlings by a mechanism that is possibly unique to plants, the ATP-, Ca2+-, and CoA-independent acylation ofphosphatidylethanolamine (PE) with unesterified free fatty acids (FFAs), catalyzed by NAPE synthase. A photoreactive free fatty acid analogue, 12-[(4- azidosalicyl)amino]dodecanoic acid (ASD), and its 125I-labeled derivative acted as substrates for the NAPE synthase enzyme.
Date: December 1998
Creator: McAndrew, Rosemary S. (Rosemary Smith)
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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Molecular Phylogeny and Evolution of the American Woodrats, Genus Neotoma (Muridae)

Description: The evolutionary relationships of woodrats (Neotoma) were elulcidated through phylogenetic analyses of mitochondrial DNA restriction site and allozyme data. DNA samples from eleven nominal species from the genus Neotoma and two outgroup taxa, Ototylomys phyttotis and Xenomys nelsoni, were cleaved using a suite of 17 Type II restriction endonucleases. Mitochondrial DNA restriction profiles were visualized following electrophoresis of restriction digests via methods of Southern transfer and hybri… more
Date: August 1992
Creator: Planz, John Valentine
Item Type: Refine your search to only Thesis or Dissertation
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The Removal of Linseed Oil Vapors by Biodegradation

Description: Linseed oil is very important in industry but its use is limited due to noxious vapors produced by oxidation on exposure to air. Since some of the products are toxic, release of linseed oil vapors to the environment is normally prohibited. In order to remove the odorous compounds, a biofilter system based on bacterial metabolism was designed and the major premises of bioremediation were studied. A total of five bacterial strains capable of using linseed oil vapors as their sources of carbon and… more
Date: August 1996
Creator: Sukplang, Patamaporn
Item Type: Refine your search to only Thesis or Dissertation
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Plankton Community Response to Dechorination of a Municipal Effluent Discharged into the Trinity River

Description: Chorine is used by the Village Creek Waste Water Treatment Plant to kill pathogenic microorganisms prior to discharge of the effluent into the Trinity River. The residual chlorine in the river impacted aquatic life prompting the U.S. Environmental Protection Agency in December 1990 to require dechlorination using sulfur dioxide. One pre-dechlorination and four post-dechlorination assessments of phytoplankton, periphyton, and zooplankton communities were conducted by the Institute of Applied Sci… more
Date: December 1994
Creator: Bryan, Brynne L. (Brynne Lee)
Item Type: Refine your search to only Thesis or Dissertation
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Chronic Ventricular Sympathectomy : Effects on Myocardial Metabolism

Description: Chronic ventricular sympathectomy elicits changes in the coronary circulation, myocardial oxygen consumption and size of infarction resulting fromcoronary occlusion. These changes indicate a change occurring in the basic metabolism of the heart in response to the removal of its sympathetic nervous input. This hypothesis was tested using two groups of dogs, a shamoperated control and a ventricular sympathectomized group. The sympathectomy procedure was an intrapericardial surgical technique whic… more
Date: August 1993
Creator: Adix Longlet, Nancy J.
Item Type: Refine your search to only Thesis or Dissertation
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Interactions between Carotid and Cardiopulmonary Baroreceptor Populations during Dynamic Exercise in Man

Description: During dynamic exercise the arterial baroreflexes have been thought to reset to the prevailing level of systemic pressure in order to modulate transient changes in blood pressure with the same sensitivity (gain) as at rest. To test this hypothesis, cardiovascular responses to dynamic exercise and carotid baroreflex responses to graded neck suction and neck pressure (NS/NP) were examined in seven men of moderate fitness (V02 = 41.4±3.6 ml O2*kg^-1*min^-1) during two levels (20% and 40% of peak o… more
Date: May 1993
Creator: Potts, Jeffrey Thomas
Item Type: Refine your search to only Thesis or Dissertation
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Nucleotide Sequence of a Bovine Arginine Transfer RNA Gene

Description: A single plaque-pure lambda clone designated λBA84 that hybridized to a ˆ32P-labeled bovine arginine tRNA was isolated from a bovine genomic library harbored in a lambda bacteriophage vector. A 2.3-kilobase segment of this clone was found to contain an arginine transfer RNAccg gene by Southern blot hybridization analysis and dideoxyribonucleotide DNA sequencing. This gene contains the characteristic RNA polymerase III split promoter sequence found in all eukaryotic tRNAs and a potential RNA pol… more
Date: May 1996
Creator: Eubanks, Aleida C. (Aleida Christine)
Item Type: Refine your search to only Thesis or Dissertation
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Pyrimidine Metabolism in Streptomyces griseus

Description: Salvage of pyrimidine nucleosides and bases by S. griseus and the regulation of aspartate transcarbamoylase (ATCase) were studied. The velocity-substrate curve for S. griseus ATCase was hyperbolic for both aspartate and carbamoylphosphate. The enzyme activity was diminished in the presence of ATP, CTP, or UTP. The synthesis of ATCase was repressed in cells grown in the presence of exogenous uracil. The specific activity of cells grown with uracil was 43 percent of that for cells grown in minima… more
Date: August 1994
Creator: Hughes, Lee E. (Lee Everette)
Item Type: Refine your search to only Thesis or Dissertation
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Subcellular Localization of N-acylphosphatidyl-ethanolamine Synthase in Cotyledons of Cotton Seedlings

Description: N-acylation of phosphatidylethanolamine (PE) with free fatty acids catalyzed by N-acyl phosphatidylethanolamine (NAPE) synthase was reported in cotyledons of 24-h-old cotton seedlings. Here I report subcellular localization of this enzyme. Differential centrifugation, sucrose density gradient fractionation,aqueous two-phase partitioning and electron microscopy techniques were utilized to elucidate subcellular site(s) of NAPE synthase. Marker enzymes were used to locate organelles in subcellular… more
Date: December 1995
Creator: Sriparameswaran, Anuja
Item Type: Refine your search to only Thesis or Dissertation
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Nesting Ecology of the Dickcissel (Spiza americana) on a Tallgrass Prairie Relict in North Central Texas

Description: Eighty-three species of vascular plants were inventoried on the prairie relict during peak dickcissel nesting. Based on foliar cover and occurrence frequency, the five dominant plants were heath aster (Aster ericoides), eastern gammagrass (Tripsacum dactyloides), little bluestem (Schizachyrium scoparium), sensitive briar (Schrankia roemeriana) and meadow dropseed (Sporobolus asper). Sixty-one percent of dickcissel nests were constructed on or immediately next to three plant species: eastern gam… more
Date: May 1993
Creator: Steigman, Kenneth Lee
Item Type: Refine your search to only Thesis or Dissertation
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Comparison of Aspartate Transcarbamoylase and Pyrimidine Salvage in Sporosarcina urea, Sprolactobacillus inulinus, Lactobacillus fermentum, and Micrococcus luteus

Description: The enzyme that catalyzes the committed step in pyrimidine biosynthesis, aspartate transcarbamoylase, has been compared in selected endospore-forming organisms and in morphologically similar control organisms. The ATCases and pyrimidine salvage from Sporosarcina ureae, Sporolactobacillus inulinus, Lactobacillus fermentum, and Micrococcus luteus were compared to those of Bacillus subtilis. While the ATCases from Sporosarcina ureae, Sporolactobacillus inulinus, and L. fermentum were found to exhi… more
Date: August 1994
Creator: Barron, Vincent N. (Vincent Neal)
Item Type: Refine your search to only Thesis or Dissertation
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Enzyme Assays Using Earthworms for Assessing Innate and Nonspecific Immunotoxicity of Xenobiotics

Description: Principal objectives of my research were to: (1) report for the first time that coelomocytes are able to reduce NBT dye and confirm the presence of lysozyme-like activity in earthworm; (2) develop a standard methodology for determination of NBT reduction and lysozyme-like activity in earthworms; (3) compare NBT reduction and lysozyme-like activity in earthworms with those of murine and human cells and fluids; and (4) demonstrate the sensitivity of earthworm NBT reduction and lysozyme-like activ… more
Date: May 1992
Creator: Chen, Shing-Chong
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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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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Regulatory Divergence of Aspartate Transcarbamoylase from the Pseudomonads

Description: Aspartate transcarbamoylase (ATCase) was purified from 16 selected bacterial species including existing Pseudomonas species and former species reassigned to new genera. An enormous diversity was seen among the 16 enzymes with each class of ATCase being represented. The smallest class, class C, with a catalytically active homotrimer, at 100 kDa, was found in Bacillus and other Gram positive bacteria. In this report, the ATCases from the Gram negatives, Shewanella putrefaciens and Stenotrophomona… more
Date: December 1996
Creator: Linscott, Andrea J. (Andrea Jane)
Item Type: Refine your search to only Thesis or Dissertation
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Naloxone Potentiation of Epinephrine Induced Vasoconstriction in Canine Skeletal Muscle Arteries

Description: Naloxone (NX) potentiated epinephrine (EPI) induced submaximal vasoconstriction in canine renal and skeletal muscle arterial segments, yet had no vasoconstrictor action alone. Developed tension generated in-vitro by 4 x 1mm. O.D. rings from 1st degree branches of canine femoral arteries was expressed as % of KCI induced maximum response. NX (10^-5 M) potentiated EPI induced submaximal contractions (34.2%) significantly more than contractions induced by norepinephrine, phenylephrine, lofexidine,… more
Date: August 1992
Creator: Stoll, Scott Thomas
Item Type: Refine your search to only Thesis or Dissertation
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Physiological Ecology, Population Genetic Responses and Assemblage Stability of Fishes in Two Southwestern Intermittent Stream Systems

Description: Six sites within the Denton and Hickory Creek watersheds were sampled over three years to assess the impact of seasonal intermittent stream conditions on the ichthyofauna. An integrated approach using field and laboratory techniques was employed to evaluate the responses of the fishes.
Date: December 1991
Creator: Rutledge, Charles Jerry, 1941-
Item Type: Refine your search to only Thesis or Dissertation
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Reciprocal Influences of Temperature and Copper on Fathead Minnows (Pimephales promelas)

Description: Acclimation temperature had a significant effect on the lethality of copper to fathead minnows in replicated 96-hour lethality tests. Lowest median lethal copper concentrations (LC50) were recorded at 12 and 22°C, with LC50s at 5 and 32°C at least 140 μg/1 higher. This research found LC50 copper concentrations in the 300 to 500 μg/1 range and a polynomial relationship between LC50s and acclimation temperature. Following a 24-hour exposure to three sublethal concentrations of copper, critical th… more
Date: May 1994
Creator: Richards, Virginia L. (Virginia Lynn)
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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