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Descriptions, Life History and Case-Building Behavior of Culoptila cantha (Trichoptera: Glossosomatidae) in the Brazos River, Texas

Description: Larval, pupal and adult samples of Culoptila cantha, from a large riffle of the Brazos River in north-central Texas from January, 1995 to March, 1997, indicated a predominately trivoltine cycle during both years; the over-wintering generation spanned 6-7 months and warm-season generations spanned 2-3 months. Eggs, larvae of all instars, larval cases, case reconstruction progression and behavior, pupae, and adults are described.
Date: August 1997
Creator: Houghton, David Charles
Item Type: Refine your search to only Thesis or Dissertation
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Detection of Mercury Among Avian Trophic Levels at Caddo Lake and Lake Lewisville, TX

Description: Mercury (Hg) is a globally distributed toxicant that has been shown to have negative effects on birds. in the United States, avian taxa have been shown to possess high Hg concentrations in the northeast, Great Lakes and Everglades ecosystems; however, few studies have measured avian Hg concentrations in other geographic regions. Previous studies have documented high Hg concentrations in multiple organisms in east Texas, but birds were not included in these studies. the main objective of the pre… more
Date: May 2012
Creator: Schulwitz, Sarah E.
Item Type: Refine your search to only Thesis or Dissertation
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Determination of Biotransformation and Biodegradation Rate Constants for Naphthalene, Lindane and Phenol

Description: Biotransformation and biodegradation rate constants were determined for naphthalene, lindane, and phenol in water samples from three different sources. Rate constants produced from monitoring disappearance of the parent chemical (biotransformation) were compared to those obtained from mineralization of the chemical (ultimate biodegradation) by ¹⁴CO₂ evolution as well as acidification of the residual ¹⁴C-labeled compound (primary biodegradation). Rate constants were statistically different for t… more
Date: December 1981
Creator: Crawford, Judith Chase
Item Type: Refine your search to only Thesis or Dissertation

Determination of Dissociation Constants for GABAA Receptor Antagonists using Spontaneously Active Neuronal Networks in vitro

Description: Changes in spontaneous spike activities recorded from murine frontal cortex networks grown on substrate-integrated microelectrodes were used to determine the dissociation constant (KB) of three GABAA antagonists. Neuronal networks were treated with fixed concentrations of GABAA antagonists and titrated with muscimol, a GABAA receptor agonist. Muscimol decreased spike activity in a concentration dependent manner with full efficacy (100% spike inhibition) and a 50% inhibitory concentration (IC50)… more
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Date: December 2005
Creator: Oli-Rijal, Sabnam
Item Type: Refine your search to only Thesis or Dissertation
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A Determination of the Effects of Various Concentrations of Sodium Chloride upon the Growth of Three Species of Bacteria

Description: The problem in this investigation is to determine the effects of various concentrations of sodium chloride upon the growth of three species of bacteria. An effort has been made to solve this problem, not only by a study of the relevant literature, but also by laboratory research consisting of cultivation and observation of the three organisms which were arbitrarily chosen for this study.
Date: 1942
Creator: Davis, J. Floyd
Item Type: Refine your search to only Thesis or Dissertation
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The Determination of Uptake and Depuration Rate Kinetics and Bioconcentration Factor of Naphthalene and Lindane in Bluegill Sunfish, Lepomis macrochirus

Description: Bluegill were exposed to 3 and 30 pg/L lindane and 20 and 200 pg/L naphthalene to determine uptake rate constants, K1 depuration rate constants, K2, and bioconcentration factors, BCF. Correlations were determined between lipid normalized and non-lipid normalized BCFs, and between observed Kl, K2 and BCFs and predicted values. The K1 values for both chemicals and concentrations were similar. The K2 values were different (1.04 day~1, 0.46 day 1). Naphthalene was more rapid. BCFs for lindane (315)… more
Date: August 1981
Creator: DeFoer, Marguerite J.
Item Type: Refine your search to only Thesis or Dissertation
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Developing a Collection Digitization Workflow for the Elm Fork Natural Heritage Museum

Description: Natural history collections house immense amounts of data, but the majority of data is only accessible by locating the collection label, which is usually attached to the physical specimen. This method of data retrieval is time consuming and can be very damaging to fragile specimens. Digitizing the collections is the one way to reduce the time and potential damage related to finding the collection objects. The Elm Fork Natural Heritage Museum is a natural history museum located at the University… more
Date: August 2013
Creator: Evans, Colleen R.
Item Type: Refine your search to only Thesis or Dissertation
open access

Development and Application of an Assessment Protocol for Watershed Based Biomonitoring

Description: With numerous bioassessment methodologies available, a regional protocol needs to be developed to ensure that results are comparable. A regional assessment protocol was developed that includes collecting five benthic macroinvertebrate samples, identifying organisms to genus, and calculating the following metrics: Number of Taxa, Total Number of Individuals, Simpson's Diversity Index, Shannon's Diversity Index, Percent Contribution of Dominant Taxa, Hilsenhoffs Biotic Index, and Percent Contribu… more
Date: May 1998
Creator: Schwartz, Joseph Howard
Item Type: Refine your search to only Thesis or Dissertation
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Development and Validation of a Ramping Treadmill Protocol for the On-Line Measurement of Four Aerobic Parameters

Description: Previously, Whipp et. al. (J. Appl. Physiol.: Respirat. Environ. Exerc. Physiol. 50(1):217-221, 1981) demonstrated the feasibility of determining four parameters of aerobic function, identified as maximum oxygen uptake (μVO_2), VO_2 at anaerobic threshold (θan), the time constant for oxygen uptake kinetics (rVO_2) and work efficiency (η), using a short duration ramped bicycle ergometer exercise test. Because of the importance of being able to measure these parameters on a variety of measurement… more
Date: May 1990
Creator: Cowell, Lynda L. (Lynda Lea)
Item Type: Refine your search to only Thesis or Dissertation
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Development of a Watershed Prioritization Strategy Using Remote Sensing and the Geographic Resource Analysis Support System. Case study: City of Carrollton, Texas

Description: This study used a geographic information system (GIS) and an empirical pollutant load model to estimate average annual pollutant loads contained in storm water charges from the City of Carrollton, Texas. The Geographic Resource Analyses Support System (GRASS) was used to create a number of spatial data layers as input variables to a model that estimates loads in Kilograms/Hectare/Year, and Kilogram/Basin/Year. Average annual pollutant loads for twelve pollutants were derived from average annual… more
Date: December 1996
Creator: Coffey, Jeffery M. (Jeffery Morgan)
Item Type: Refine your search to only Thesis or Dissertation
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Development of an In Vitro Protoplast Culture System for Albizia Lebek (L.) Benth., an Economically Important Leguminous Tree

Description: An in vitro system of generating protoplasts from their callus cultures was established. The friable callus was more productive in terms of producing protoplasts than the green compact callus. The concentration of the various cell wall degrading enzymes had an effect on the viability of the protoplasts in the medium. The protoplast system developed from the experiments was stable and could be used for the transformation experiments of Albizia lebek and for other plant improvement practices.
Date: August 1998
Creator: Sinha, Debleena
Item Type: Refine your search to only Thesis or Dissertation
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Development of Range Condition Classes for Coleman County, Texas

Description: This paper deals with a study of the rangelands in Coleman County just west south and west of the Western Cross Timbers of Texas. This problem consists of classifying certain rangelands in this area according to whether they are excellent, fair, good, or poor, the chief basis for which is their deterioration.
Date: June 1951
Creator: McMinn, Philip Morris
Item Type: Refine your search to only Thesis or Dissertation
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Developmental Patterns of Metabolism and Hematology in the Late Stage Chicken Embryo (Gallus Domesticus) at Two Incubation Temperatures.

Description: How temperature affects physiological development in the chicken embryo is unknown. Embryos incubated at 38°C or 35°C showed no difference in growth or survival. The time to hatching was longer in 35°C than 38°C embryos (23.7 vs. 20.6 days), but unaffected was the relative timing of appearance of developmental landmarks (internal, external pipping). At stage 43-44, 38°C embryos maintained oxygen consumption around 1 mL/g/h despite acute temperature reduction (suggesting thermoregulatory maturat… more
Date: May 2003
Creator: Black, Juli
Item Type: Refine your search to only Thesis or Dissertation
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Differences in Protein Constituents of Some Azotobacter Species

Description: This study used polyacrylamide gel electrophoresis to study the acid-phenol soluble proteins of five strains (A. vinelandii 12837, A. vinelandii 0, A. chroococcum 8004, A. macrocytogenes 8702, A. tumefaciens) of bacteria grown on Burk's nitrogen-free media, Trypticase Soy Broth, and 0.3% butanol medium. The results showed that the protein patterns can be used for the identification and possibly the taxonomic classification of the Azotobacter. The change of phenotype of the bacteria in different… more
Date: August 1975
Creator: Hsu, Li-Chu Yao
Item Type: Refine your search to only Thesis or Dissertation
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Diphenyloxazole Metabolism by Aryl Hydrocarbon Hydroxylase

Description: 2,5-Diphenyloxazole (PPO) was tested as a potential alternate inducer for the aryl hydrocarbon hydroxylase (AHH) system. Its apparent lack. of carcinogenicity and toxicity provide a possible system for investigation of enzyme systems related to chemical carcinogenesis without exposure of the researcher to potent carcinogenic compounds. These studies found PPO to be an inducer of AHH in cultured human lymphocytes. When PPO was utilized as a substrate for the AHH assay system, the major metabolit… more
Date: December 1976
Creator: Abreu, Mary E.
Item Type: Refine your search to only Thesis or Dissertation
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Distribution, Abundance, and Food Habits of Larval Fish in a Cooling Reservoir

Description: Analysis of larval fish collected at four stations in a 330-ha cooling reservoir indicated Dorosoma spp. were most numerous at all stations, followed by Lepomis spp. and Percina Macrolepida. Largest numbers and greatest diversity of larval fish were found at the station least affected by thermal effluent; the mid-lake station provided the smallest numbers and least diversity. The two warmwater stations were intermediate, with similar numbers and diversity. Diversity and abundance of zooplankton… more
Date: December 1978
Creator: Mitterer, Lana Gayle
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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The Distribution of Pathogenic Pseudomonas aeruginosa in Sewage

Description: The purpose of this study was to extend our understanding of the ecological relationships of P. aeruginosa by investigating the differences or similarities between the strains of this organism found in sewage and those found as pathogens in human infections. This research was approached by comparing the serological types of P. aeruginosa isolated from sewage contaminated waters in Argentina (South America) to those isolated from sewage contaminated waters in Texas. They were typed with sera obt… more
Date: May 1974
Creator: Labay, Joseph Edward
Item Type: Refine your search to only Thesis or Dissertation
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Distribution of Phosphates in a Sewage Plant and its Receiving Waters

Description: The purpose of this paper is to detail the distribution and quantity of soluble phosphates in an activated sludge plant, its discharge creek, and receiving reservoir. The resultant analyses and comparison of data should provide some better understanding of the fate of phosphorus in a Southwestern waterway system.
Date: May 1969
Creator: Hansard, John D.
Item Type: Refine your search to only Thesis or Dissertation
Location: None
open access

Distribution, Size, Condition, and Food Habits of Selected Fishes in a Reservoir Receiving Heated Effluent from a Power Plant

Description: This study was undertaken in order to provide further insight into the effects of artificial heating on the fisheries of a small reservoir in the Southwest. The following specific objectives were established: (1) to map the reservoir for the distribution of heated water, (2) to determine the distribution of selected species of sports, rough, and forage fish in areas affected by the effluent and in areas not affected, (3) to compare size and condition of selected species of fish from areas affec… more
Date: December 1972
Creator: McNeely, David L.
Item Type: Refine your search to only Thesis or Dissertation
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