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The Cultural, Physiological, Morphological and Chemical Characteristics of an Actinomycete from Lake Waco, Texas

Description: The purpose then of this paper has been to expand our knowledge of these aquatic forms by investigating the cultural, physiological, morphological, and chemical characteristics of an actinomycete isolated from the water supply, Lake Waco, of Waco, Texas.
Date: January 1954
Creator: McCormick, William C.
Item Type: Refine your search to only Thesis or Dissertation
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Spring Food Habits of Corydalus Cornutus L. in the Brazos River, Texas

Description: The objective of this study was to determine the kinds and numbers of food organisms consumed by Corydalus cornutus, and to investigate its periodicity of feeding during the spring months in the Brazos River, Palo Pinto County, Texas. A total of 468 larvae were collected at two-week intervals from February 29 to May 14, 1971. Larvae were taken at opportunity during three periods of the day, 6am.-12pm., 12pm.-6pm., and 6pm.-12am. A total of 23 different food items was observed in the 121 stomach… more
Date: August 1971
Creator: Friday, Gary P.
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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Examining the Shade/flood Tolerance Tradeoff Hypothesis in Bottomland Herbs Through Field Study and Experimentation

Description: While there is growing evidence that shade/flood tolerance tradeoffs may be important in distributions of bottomland hardwood trees and indications that they should apply to herbs, no studies have definitively explored this possibility. Four years of field data following historic flooding were supplemented with a greenhouse experiment designed to identify interactions congruent with tradeoffs. Fifteen bottomland species were grown in two levels of water availability and three levels of shade ov… more
Date: May 2012
Creator: Sloop, Jordan
Item Type: Refine your search to only Thesis or Dissertation
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Ecology and Recolonization of Benthic Macroinvertebrates in a Groundwater-dependent Stream in North Central Texas During a Supra-seasonal Drought

Description: Extreme climatic events such as droughts are known to eliminate aquatic biota and alter community structure and function. Perennial headwater springs provide important drought refugia to benthic macroinvertebrates and an important source of colonists via drift or aerial adults to intermittent streams post-drought. During a supra-seasonal drought in North-central Texas summer and fall 2006, benthic macroinvertebrates from persistent groundwater-dependent macrohabitats of varying hydrological con… more
Date: May 2012
Creator: Burk, Rosemary A.
Item Type: Refine your search to only Thesis or Dissertation
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Investigating Realistic Scenarios of Biodiversity Loss on Ecosystem Functioning: Extirpation of Rare Species and Food Web Collapse in Tropical Floodplain Lagoons

Description: This thesis investigates the influence of nonrandom species loss on the structure and functioning of trophic floodplain lagoons. Two experiments were conducted based on different realistic scenarios of biodiversity loss using multitrophic fish assemblages derived from long-term survey data. Loss of fish diversity influenced overall ecosystem multifunctionality of these lagoons through complex multitrophic interactions throughout the aquatic food web. These results indicate that biodiversity l… more
Date: May 2012
Creator: Pendleton, Richard McCall
Item Type: Refine your search to only Thesis or Dissertation
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Some Relationships between Certain Aquatic Actinomycetes and Bacillus Cereus

Description: The purpose of this investigation is to determine if there was a metabolic relationship between the actinomycetes and the gram positive, spore-forming becilli in surface waters, and, if such a relationship was evident, to relate the association to the disappearances of typical actinomycete tastes and odors from waters.
Date: August 1963
Creator: Hoehn, Robert Campbell
Item Type: Refine your search to only Thesis or Dissertation
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Effects of pH and Substrate on Growth of Escherichia Coli and Pseudomonas Aeruginosa in Mixed Continuous Culture

Description: The express purpose for doing this project was to develop methods for the continuous culture of E. coli and P. aeruginosa as a mixed population, and to apply these methods in studying the effects of pH and substrate upon the growth of these two organisms in mixed continuous culture.
Date: January 1964
Creator: Cooper, Billy Howard
Item Type: Refine your search to only Thesis or Dissertation
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Some Effects of X-irradiation on the Plasma Corticosterone, Adrenal Weights, and Differential Leukocyte Count in the Rat

Description: The purpose of the present study was twofold: (1) to determine if X-irradiation can be considered a direct stress agent, and if so, to what extent it differs from other stressors; and (2) to further elucidate the role of the adrenal cortex in the radiation syndrome by determining the more immediate responses of this system to X-irradiation.
Date: August 1962
Creator: Gaugl, John F.
Item Type: Refine your search to only Thesis or Dissertation
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An Investigation of Methods for the Concentration of Chemical Compounds Produced by Actinomycetes and Their Relation to Tastes and Odors in Municipal Water Supplies

Description: It is the purpose of this investigation to improve upon techniques to enhance the taste of municipal water and attempt to devise one that could desorb the compounds from carbon in an unaltered state. It was decided that the odor character would be the criterion used to decide if the eluted compounds were the same as those in the raw water.
Date: 1957
Creator: Brown, Jerry H.
Item Type: Refine your search to only Thesis or Dissertation
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A Study of Selected Factors Related to Permanency in Science Teaching

Description: The purpose of this study is to gather information related to some factors which are considered to be characteristic of science teaching; to attempt to identify some elements of permanency in science teaching; and to analyze some relationships between the results of the above two criteria with the view of establishing some factors which may be useful as predictors of permanency, or indicative of patterns of permanency, in science teaching.
Date: August 1958
Creator: Lovelace, Allen J.
Item Type: Refine your search to only Thesis or Dissertation
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