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An Investigation of Naturally Occurring Tastes and Odors from Fresh Waters

Description: The Problem of the cause and control of tastes and odors in water supplies has been the subject of a great many investigations during the last half-century; however, many questions in this field remain to be answered. Theories relating to the cause of tastes and odors occurring in water are still rather numerous and, at present, only a few of them are compatible. Although several procedures have been employed for the eradication of tastes and odors from water supplies, none of them are complete… more
Date: May 1955
Creator: Pipes, Wesley O'Feral, Jr.
Item Type: Refine your search to only Thesis or Dissertation
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Investigation of Pyrimidine Salvage Pathways to Categorize Indigenous Soil Bacteria of Agricultural and Medical Importance and Analysis of the Pyrimidine Biosynthetic Pathway's Enzyme Properties for Correlating Cell Morphology to Function in All Phases of Growth

Description: This dissertation comprises three parts and is presented in two chapters. Chapter 1 concerns Arthrobacter, a bacterium with an intriguing growth cycle. Whereas most bacteria exist as either a rod or coccus, this bacterium shares the rod/coccus lifestyle. It therefore seemed important to examine the growth regulatory pathways from the rod and coccus. The committed step, that catalyzed by aspartate transcarbamoylase (ATCase), in the pyrimidine biosynthetic pathway was chosen. The ATCase in Arthr… more
Date: May 2003
Creator: Meixner, Jeffery Andrew
Item Type: Refine your search to only Thesis or Dissertation
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An Investigation of Selected Factors Related to the Professional Status of the Science Teachers in the Four-Year Accredited High Schools of Texas for the School Year 1952-1953

Description: The purpose of this study is to gather information related to the professional status of the science teachers in the four-year accredited high schools of Texas for the school year 1952-1953. The principal concern of the study is "Who is teaching science?"
Date: August 1953
Creator: Whitehead, Oren W.
Item Type: Refine your search to only Thesis or Dissertation
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Investigations of neuronal network responses to electrical stimulation in murine spinal cultures.

Description: Spontaneous activity in neuronal networks in vitro is common and has been well documented. However, alteration of spontaneous activity in such networks via conditioning electrical stimulation has received much less experimental attention. Two different patterns of electrical stimulation were used to enhance or depress the level of spontaneous activity in spinal cord cultures. High-frequency stimulation (HFS), a method routinely shown to increase the efficacy of synaptic transmission, was employ… more
Date: December 2001
Creator: Sparks, Christopher A.
Item Type: Refine your search to only Thesis or Dissertation
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Investigations on Abundance, Habits, and Distribution of Amphibians and Reptiles of Denton County, Texas

Description: The purpose of the present study of the herpetofauna was to obtain additional information regarding the vertebrates of Denton County, and to produce a well-preserved, cataloged collection of the amphibians and reptiles for the Museum of Zoology, North Texas State University. An understanding of the vertebrate life of the county also involves an investigation of the habitats within the county that may, in part, count for the distribution of these animals. It is well recognized that the environme… more
Date: January 1967
Creator: Telfair, Raymond Clark
Item Type: Refine your search to only Thesis or Dissertation
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Isolation and Bioinformatic Characterization of Four Novel Bacteriophages from Streptomyces toxytricini

Description: Six initial phage isolates with high titer lysates were obtained using Streptomyces toxytricini B-5426 as the host bacterium. These isolates were named Goby, Toma, Yosif, Yara, Deema, and Hsoos. However, upon completion of the sequencing, it was found that the Yara and Hsoos isolates were identical, as were Goby and Deema. As a result, final analysis was completed on only the four unique isolates. All of the phages mentioned above were isolated from soil samples from different locations. Al… more
Date: May 2019
Creator: Alzaid, Hessah
Item Type: Refine your search to only Thesis or Dissertation
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The Isolation and Characterization of a Hitherto Undescribed Gram-Negative Bacterium

Description: A unique undosciribed gramnegative rod is extensively characterized in this study. The cells of this unusual water isolate measure 1.2 X 6.5 microns, The most distinguishing characteristic of the bacterium is a polar tuft of 35-40 flagella that aggregate to function as a single organelle which is visible under phase contrast. Aging cells deposit poly- -hydroxybutyric acid granules which are bound by an inclusion membrane made up of four distinct layers. It also possesses an unusual exterior mem… more
Date: August 1972
Creator: Lassiter, Carroll Benson
Item Type: Refine your search to only Thesis or Dissertation
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Isolation and Characterization of a New Capsule-Forming Bacterium

Description: A unique, previously undescribed Gram-negative bacterium was isolated from several soils in Texas and extensively characterized in this study. The cells measured 1-2 by 4-6 μm. The distinguishing characteristic of the bacterium is the extraordinary capsular material which surrounds the cells. The new isolates are aerobic, mesophilic, non motile and have the ability to utilize a variety of organic compounds as the sole source of carbon and energy. The organism grows optimally at 30° C and the op… more
Date: May 1999
Creator: Thongmee, Acharawan
Item Type: Refine your search to only Thesis or Dissertation
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Isolation and Characterization of Malic Enzyme from Ascaris suum

Description: A procedure for the isolation of malic enzyme from muscle tissue of the roundworm Ascaris suum is described. The fractionation method yields relatively large quantities of the enzyme,with a specific activity of fifteen moles of malate converted to pyruvate and carbon dioxide per min per mg at 25º. Homogeneity was established with analytical ultracentrifugation, zone electrophoresis, isoelectric focusing, and rechromatography. The molecular weight of the enzyme was 250,000, and it is dissociated… more
Date: December 1972
Creator: Fodge, Douglas W.
Item Type: Refine your search to only Thesis or Dissertation
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Isolation and Identification of an Odor Compound Produced by a Selected Aquatic Actinomycete

Description: The purpose of this study was to develop an efficient method for the concentration of specific volatile taste and odor compounds produced by a selected aquatic actinomycete. A second purpose was to isolate and identify the specific taste and odor compound present in the highest concentration.
Date: August 1968
Creator: Henley, Don E.
Item Type: Refine your search to only Thesis or Dissertation
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Isolation and Identification of Bacterial Species Associated with the Common House Fly and Three Species of Cockroaches

Description: In an attempt to demonstrate the role of insects as possible carriers of pathogenic bacterial organisms this investigation has been concerned with the determination of the microbial population associated both internally and externally with the common house fly and three species of the cockroach.
Date: 1951
Creator: Morland, Clifford L.
Item Type: Refine your search to only Thesis or Dissertation
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Isolation and Partial Characterization of a Bacterium Which Gives Off Filtrable Cells

Description: The present study was on the isolation of a bacterium capable of producing filtrable forms which passed through the 0.45µ filter membrane and regenerated the parental form; the testing of the true filtrability of the isolate; the relationship between growth of the isolate and appearance of filtrability; partial characterization of the isolate and visualization of the elements that passed through the membrane filter with electron microscopy and shadow casting technique.
Date: May 1973
Creator: Siu, Henry H. W.
Item Type: Refine your search to only Thesis or Dissertation
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Isolation and Partial Characterization of Carotenoid Pigments of Mycobacterium Rhodochrous

Description: It was the purpose of this investigation to isolate and characterize the pigments of Mycobacterium rhodochrous by partition behavior, chromatographic data, and absorption spectra. In addition, it was the purpose to determine whether or not the type of pigments found in M. rhodochrous is typical of those found in other mycobacteria.
Date: August 1971
Creator: Jorgensen, Joyce A.
Item Type: Refine your search to only Thesis or Dissertation
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Isolation and Partial Characterization of Pigment Mutants of Corynebacterium poinsettie ATCC 9682

Description: Carotenoid pigments were extracted from Corynebacteriuma poinsettiae (wild type) ATCC 9682, and from 108 mutants obtained by exposure of a streptomycin resistant strain of C. poinsettiae to ultra-violet light irradiation and N-methyl- N'-nitro-N-nitrosoguanidine. The pigments were characterized by their absorption maxima, Rf-values, and partition ratios in petroleum ether and methanol. Thin layer chromatography was used to compare pigments of the wild type with those of the mutants. Possible bi… more
Date: August 1980
Creator: Wariso, Benjamin A.
Item Type: Refine your search to only Thesis or Dissertation
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Isolation, Characterization and Physiological Studies of Cyanide-Utilizing Bacteria

Description: Ten bacteria capable of growth on the metal-cyano complex, tetracyanonickelate (II) {K2 [Ni(CN)J } (TCN), supplied as the sole nitrogen source, were isolated. Seven isolates were identified as pseudomonads while the remaining three were classified as Klebsiella species. In addition to TCN, all isolates were able to utilize KCN although it was significantly more toxic. The degradation of TCN was most complete when supplied at growth-limiting concentrations, did not occur when ammonia was present… more
Date: December 1991
Creator: Silva Avalos, Juan G. (Juan Guillermo)
Item Type: Refine your search to only Thesis or Dissertation
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The Isolation, Cultivation and Testing of Organisms Anatagonistic to a Streptomycin Resistant Strain of Pseudomonas Aeruginosa

Description: The problem of finding an efficient antibiotic against Pseudomonas aeruginosa which can be used in the clinical treatment of genito-urinary tract infections resistant to treatment by streptomycin has not yet been solved. Therefore, this problem has consisted of first, the acquisition of possible inhibitors of the streptomycin resistant strain of Pseudomonas aeruginosa; second, the selection and identification of those which show a marked antagonism toward this organism; third, the determination… more
Date: 1951
Creator: Banister, Jack Warren
Item Type: Refine your search to only Thesis or Dissertation
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Isolation, Identification and Cultivation of Four Phytopathogenic Fungi

Description: This investigation includes a morphological and cultural study of four rather common pathogenic fungi one of which attacks Zinnia elegans, one Lagerstroemia indica, one Ligustrum lodense and one Euonymus japonica. The problem includes, first, a determination of the genera of these four fungi as revealed by their morphology in natural habitat; second, a determination of the growth and cultural characteristics of these on Cornmeal, Potato, Bean, Prune and Carrot agars; third, a comparison of the … more
Date: 1951
Creator: Parks, Leroy W.
Item Type: Refine your search to only Thesis or Dissertation
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Key Factors Influencing Retention Rates among Historically Underrepresented Student Groups in STEM Fields

Description: The aim of the study was to identify the factors that have an influence on the completion rates of undergraduate students in the fields of science, technology, engineering and mathematics (STEM). Using Tinto's retention rate theory as the theoretical foundation, data were collected from freshman who were enrolled in the years 2005 to 2008. Results showed gender and first-generation status were significant predictors of STEM completion and time taken to complete the degree. Institutional bias pl… more
Date: December 2018
Creator: Premraj, Divya
Item Type: Refine your search to only Thesis or Dissertation

A laboratory course in experimental genetics for the biology major.

Description: This manual has been designed for a class of twenty- four students concurrently enrolled in the lecture course. The laboratory aids in the learning process and fosters an interest in the science of genetics. This manual and the experiments contained within are both informative and fun. The manual correlates with and expands upon the genetics course. Each investigation, with the exception of the Drosophila melanogaster project, can be completed in a 3-4 hour timeframe. This manual provides a “ha… more
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: December 2001
Creator: Lux, Melissa McNeil
Item Type: Refine your search to only Thesis or Dissertation
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Lactate Dehydrogenase of Hymenolepis Diminuta: Isolation and Characterization

Description: Lactate dehydrogenase was isolated in pure form from crude extract of the cestode Hymenoleois diminuta by heat treatment and column chromatography. The purified enzyme has a specific activity of 106 units per mg protein. The molecular weight of the purified protein was 75,000 as determined by Sephadex gel filtration and analytical ultracentrifugation. An equilibrium ultracentrifugation study suggests a subunit molecular weight of 39,000. From these data, a dimer form of the native enzyme is pro… more
Date: December 1971
Creator: Burke, William F.
Item Type: Refine your search to only Thesis or Dissertation
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Landscape Ecological Characteristics of Habitat of the Red-cockaded Woodpecker

Description: Geographic information systems (GIS) technology was used to analyze factors influencing habitat use by an endangered species, the red-cockaded woodpecker. The study area was the western part of the Raven Ranger District of the Sam Houston National Forest, Texas. The factors considered included both structural characteristics and spatial relationships among stands of trees in the habitat.
Date: December 1993
Creator: Thomlinson, John Richard
Item Type: Refine your search to only Thesis or Dissertation
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