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  Partner: UNT Libraries
 Department: Department of Biological Sciences
Alterations in Fatty Acid Amide Hydrolase (Faah) Transcript Levels and Activity Lead to Changes in the Abiotic Stress Susceptibility of Arabidopsis Thaliana

Alterations in Fatty Acid Amide Hydrolase (Faah) Transcript Levels and Activity Lead to Changes in the Abiotic Stress Susceptibility of Arabidopsis Thaliana

Date: May 2012
Creator: Gonzalez, Gabriel
Description: N-Acylethanolamines (NAEs) are a class of bioactive lipids, and FAAH is one of the enzymes responsible for degrading NAEs in both plants and animals. in plants, FAAH appears to be closely associated with ABA, a phytohormone which has long been associated with plant stress responses, since the overexpression of FAAH in Arabidopsis results in ABA hypersensitivity. Therefore, it is reasonable to speculate that alterations in FAAH transcript levels will result in altered stress responses in plants. to investigate this hypothesis experiments were carried out in which wild type (WT), FAAH-overexpressing (OE), and T-DNA insertional FAAH knockouts of Arabidopsis (faah) were grown in MS media under stress conditions. the stress conditions tested included chilling stress, heavy metal stress induced by cadmium or copper, nutrient limitations induced by low phosphorus or low nitrogen, salt stress induced with NaCl, and osmotic stress induced with mannitol. the OE plants were consistently hypersensitive to all stress conditions in relation to wild type plants. Inactive FAAH overexpressors did not have the hypersensitivity to the salt and osmotic stress of the active OE plants and were instead tolerant to these stresses. FAAH2 (faah2) knockouts and FAAH 1 and 2 double knockouts (faah 1+2) were based on some ...
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Ecology and Recolonization of Benthic Macroinvertebrates in a Groundwater-dependent Stream in North Central Texas During a Supra-seasonal Drought

Ecology and Recolonization of Benthic Macroinvertebrates in a Groundwater-dependent Stream in North Central Texas During a Supra-seasonal Drought

Date: May 2012
Creator: Burk, Rosemary A.
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 connectivity and riparian shading were studied: perennial riffles, connected pools, shaded disconnected pools, and full sun disconnected pools. Riffles were a distinct habitat with significantly higher taxa richness, proportion of lotic taxa, diversity and evenness than other macrohabitats. Macrohabitats were found to be important refugia for 106 benthic macroinvertebrates and 4 microcrustacean taxa. Throughout the extreme drought, perennially flowing habitats were refugia to 19 taxa (17.9% total taxa) not collected in disconnected pools. Shaded disconnected pools contained lotic taxa not previously known to be able to complete their lifecycles in lentic habitats, emphasizing the importance of groundwater effluent and shading. With the resumption of flow at a downstream intermittent site of Ash Creek in mid-October 2006, an annual recolonization study was conducted comparing the perennial headwaters’ benthic macroinvertebrate taxa richness, densities and community ecology with the downstream ...
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Individual, Social, and Seasonal Behavior of the Thirteen-Lined Ground Squirrel (Spermophilus tridecemlineatus)

Individual, Social, and Seasonal Behavior of the Thirteen-Lined Ground Squirrel (Spermophilus tridecemlineatus)

Date: January 1970
Creator: Wistrand, Harry E.
Description: The purpose of this study is to provide a qualitative, detailed description of individual and social behavior in a free-living population of thirteen-lined ground squirrels. Behavioral differences in relation to various periods of the annual cycle are also evaluated.
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Influence of Acclimation and Acclimatization to Seasonal Temperatures on Metabolism and Energetics in the Rusty Lizard Sceloporus Olivaceus

Influence of Acclimation and Acclimatization to Seasonal Temperatures on Metabolism and Energetics in the Rusty Lizard Sceloporus Olivaceus

Date: May 1973
Creator: Dutton, Ronald Hugh
Description: Rates and energy equivalents of consumption (C), egestion+ excretion (FU) , assimilation (A), respiration (R) and production (P) were measured in two groups of Sceloporus olivaceus: 1) a laboratory group acclimated at four seasonally encountered temperatures (15, 20, 25 and 30°C) ; and 2) four acclimatization groups collected at different seasons when ambient temperatures corresponded to 15, 20, 25 and 30°C.
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Experimental Trichinosis in Birds

Experimental Trichinosis in Birds

Date: December 1970
Creator: Poon, Yau-Lun
Description: This work concerns itself with essentially four experiments: (1) the cecum-injective-infection experiment; (2) the anus-injective-infection experiment; (3) the mouth ingestive-infection with larvae, and (4) the mouth ingestive-infection with the flesh of infected rats.
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Mixed Culture of Chlorella Pyrenoidosa TX71105 and a Variant Strain of Bacillus Megaterium

Mixed Culture of Chlorella Pyrenoidosa TX71105 and a Variant Strain of Bacillus Megaterium

Date: August 1970
Creator: Yao, Raymond Che-Fong
Description: Very little work has been done on bacteria capable of significantly inhibiting algal growth. This thesis reports the research on mixed cultures of a high-temperature strain of algae, Chlorella pyrenoidosa TX71105, and an organism isolated from the air and tentatively identified as a variant strain of Bacillus megaterium.
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Obligately Thermophilic Nitrogen-Fixation in Some Soil Bacteria

Obligately Thermophilic Nitrogen-Fixation in Some Soil Bacteria

Date: August 1971
Creator: Milam, Mary
Description: In the work presented here, it is claimed that bacteria have been isolated which are capable of growth at high temperatures utilizing molecular nitrogen as their sole nitrogen source. Soil bacteria were isolated which grew at 55 C in nitrogen-free media. They were found to be obligatory thermophiles in nitrogen-free media and facultative thermophiles in media containing organically bound nitrogen.
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The Larval Lipids of the Chironomid Midge Glyptotendipes Barbipes (Staeger)

The Larval Lipids of the Chironomid Midge Glyptotendipes Barbipes (Staeger)

Date: December 1971
Creator: Talent, John M.
Description: This problem was concerned with determining the total lipid content and individual lipid composition of the larvae of a local chironomid, Glyptotendipes barbipes (Staeger).
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Some Effects of Electrostatic Fields on Brain Activity in Rats

Some Effects of Electrostatic Fields on Brain Activity in Rats

Date: December 1971
Creator: McCain, Harry B.
Description: This study concerned the effects of short-term exposures to continuous (10 kv/meter) and pulsed 20 volts at 640 cps/100 msecs) electrostatic fields on the EEG recorded from external electrodes and hypothalamic activity recorded from implanted electrodes in rats. Each experiment lasted at least 90 minutes. The total energies of the waveforms recorded were integrated and printed out for plotting and analysis. Besides the brain activity, the ECG, respiration, and temperature of the animals were also monitored before, during,and after exposure to the electrostatic fields.
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A Carcinogenic Agent Elaborated by Liver Cells from Lymphosarcoma-Bearing Mice

A Carcinogenic Agent Elaborated by Liver Cells from Lymphosarcoma-Bearing Mice

Date: August 1972
Creator: Blachley, Jon David
Description: Liver cells from lymphosarcoma-bearing DBA/1J mice were shown, by parabiotic culture with normal liver cells from isologous mice, to elaborate an agent which could pass a 25 mu filter and transform the normal cells to a malignant state.
Contributing Partner: UNT Libraries
Effect of Indole-3-Acetic Acid on the Nucleic Acids of Synchronous Cultures of Chlorella Pyrenoidosa

Effect of Indole-3-Acetic Acid on the Nucleic Acids of Synchronous Cultures of Chlorella Pyrenoidosa

Date: May 1972
Creator: Peterson, James Arthur
Description: It was the purpose of this study to investigate the effect of various concentrations of IAA on the nucleic acids of Chlorella pyrenoidosa TX 7-11-05. The time during the life cycle when the greatest effect occurred was investigated by the use of synchronous cultures.
Contributing Partner: UNT Libraries
Effects of 2-Chloroethylphosphonic Acid (Ethephen) on Scenedesmus Quadricauda

Effects of 2-Chloroethylphosphonic Acid (Ethephen) on Scenedesmus Quadricauda

Date: August 1973
Creator: Chapman, Richard W.
Description: The effects of various concentrations of 2-chloroethylphosphcnic acid (Ethephon), an ethylene-releasing compound, on the total protein, deoxyribonucleic acid (DNA), and ribonucleic acid (RNA) levels in Scenedesmus quadricauda IU 614 were investigated.
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Proteomic Responses in the Gill of Zebrafish Following Exposure to Ibuprofen and Naproxen

Proteomic Responses in the Gill of Zebrafish Following Exposure to Ibuprofen and Naproxen

Date: August 2012
Creator: Adhikari, Prem R.
Description: Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most abundant environmental pharmaceutical contaminants. In this study, a proteomic analysis was conducted to identify proteins differentially expressed in gill tissue of zebrafish (Danio rerio) after a 14-day exposure to the NSAIDs ibuprofen or naproxen. A total of 104 proteins with altered expression as indicated by 2-dimensional electrophoresis were analyzed by liquid chromatography with ion trap mass spectrometry (MS/MS). A total of 14 proteins fulfilled our requirements for identification which included consistency among replicate gels as well as successful MS/MS ion searches with the MASCOT database. The most prominent feature of the differential protein expression observed after NSAID exposure was an up-regulation of proteins belonging to the globin family which are involved in the transport of oxygen from gills and availability of heme molecules required for synthesis of cyclooxygenase. Differential expression was observed at exposure concentrations as low as 1-10 µg/L indicating that altered gene expression may occur in fish subjected to environmentally realistic levels of NSAID exposure.
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Modeling the Relationship Between Golden Algae Blooms in Lake Texoma, Usa, Versus Nearby Land Use and Other Physical Variables

Modeling the Relationship Between Golden Algae Blooms in Lake Texoma, Usa, Versus Nearby Land Use and Other Physical Variables

Date: August 2012
Creator: Ware, Trudy M.
Description: Pyrmnesium parvum, commonly known as golden algae, is an algal species that under certain circumstances releases toxins which can lead to fish kills and the death of other economically and ecologically important organisms. One of the major objectives of the study was to investigate whether a relationship exists between land use and Prymnesium parvum abundance in littoral sites of Lake Texoma, USA. Another objective was to investigate whether a relationship exists between other physical variables and counts of P. parvum. Lastly, developing a valid model that predicts P. parvum abundance was an objective of the study. Through stepwise regression, a small but highly significant amount of the variation in P. parvum counts was found to be explained by wetlands, soil erodibility and lake elevation. The developed model provides insight for potential golden algae management plans, such as maintaining wetlands and teaching land owners the relationship between soil erosivity and golden algae blooms.
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A Socio-ecological Assessment of Watershed Ecosystem Services in Southern Patagonia

A Socio-ecological Assessment of Watershed Ecosystem Services in Southern Patagonia

Date: August 2012
Creator: Zagarola, Jean-Paul Aguirre
Description: This thesis utilizes a theoretical framework which links biophysical and social domains of ecosystems via ecosystem services (ES), in order to conduct a socio-ecological assessment of urban watersheds in three communities in Chilean and Argentine regions of southern Patagonia. Results from this study show that expanding urban areas may be undermining the ability of local watersheds to provide for high quality ES posing potential risks to community wellbeing. Secondly, researchers and decision makers influencing regional natural resource management share similar values to general community members but do not capture the diversity of values that exist within the broader community, and dialogue between these groups on management issues is poor. A community-based management structure is recommended for the creation of adaptive and locally relevant management strategies.
Contributing Partner: UNT Libraries
Optimizing Scientific and Social Attributes of Pharmaceutical Take Back Programs to Improve Public and Environmental Health

Optimizing Scientific and Social Attributes of Pharmaceutical Take Back Programs to Improve Public and Environmental Health

Date: August 2012
Creator: Stoddard, Kati Ireland
Description: Research continues to show that pharmaceutical environmental contamination has caused adverse environmental effects, with one of the most studied effects being feminization of fish exposed to pharmaceutical endocrine disruptors. Additionally, there are also public health risks associated with pharmaceuticals because in-home reserves of medications provide opportunities for accidental poisoning and intentional medication abuse. Pharmaceutical take back programs have been seen as a remedy to these concerns; however a thorough review of peer-reviewed literature and publicly available information on these programs indicates limited research has been conducted to validate these programs as a purported solution. Furthermore, there are significant data gaps on key factors relating to take back program participants. The purpose of this dissertation was therefore to address these gaps in knowledge and ultimately determine if take back programs could actually improve public and environmental health. This was accomplished by conducting social and scientific research on a take back program called Denton Drug Disposal Day (D4). Socioeconomic, demographic, and geographic characteristics of D4 participants were investigated using surveys and geographic analysis. Impacts on public health were determined by comparing medications collected at D4 events with medications reported to the North Texas Poison Center as causing adverse drug exposures in Denton ...
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Hypoxia and the Development of Endothermic Capacity in Chickens (Gallus Gallus)

Hypoxia and the Development of Endothermic Capacity in Chickens (Gallus Gallus)

Date: August 2012
Creator: Neely, Aaron Mackallan
Description: Adult chickens employ endothermy – internal generation of heat that maintains a constant body temperature (Tb). Prior to hatching, chicken embryos are ectothermic - controlling Tb by external heat sources. Upon hatching, the hatchling transitions from an ectotherm to an endotherm that has been shown to be delayed by hypoxia. In this study, whole animal oxygen consumption () and liver, heart, and skeletal muscle citrate synthase activity (CSA) and were measured during this transition to endothermy in chickens incubated in normoxia and hypoxia (15% O2). The only significant differences in occurred in 48 hour old hatchlings where was lower in normoxic hatchlings. There were no differences in CS activity between age and incubation oxygen levels. Additionally, preliminary 2-D protein gels of embryo and hatchling liver show changes in the proteome upon hatching. Results suggest that hypoxia had no significant effect on CSA and a minimal effect on .
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Effects of a Methylcholanthrene-Induced Lymphosarcoma on the Blood of DBA/1J Mice

Effects of a Methylcholanthrene-Induced Lymphosarcoma on the Blood of DBA/1J Mice

Date: May 1972
Creator: Lindsey, Jerri Kay
Description: This investigation was concerned with characterizing a tumor line induced and maintained in this laboratory. Various chemical assays, cell counts, and electron microscopy were the methods employed to characterize the blood of mice bearing the tumor at days 3, 6, 9, and 12 after injection of the 1.2 x 10^8 tumor cells.
Contributing Partner: UNT Libraries
Studies on the Morphology and Biology of Cotton Rats (Sigmodon hispidus) from Northern Mexico to Southern Nebraska

Studies on the Morphology and Biology of Cotton Rats (Sigmodon hispidus) from Northern Mexico to Southern Nebraska

Date: December 1971
Creator: Cleveland, Arthur Gordon
Description: This investigation was designed to evaluate the need for retaining both Sigmodon hispidus texianus and Sigmodon hispidus berlandieri as subspecific designations. An attempt was made to demonstrate bioclimatic variation and reproductive seasonality in cotton rats. The validity of applying the results of isolated studies of cotton rat populations to the species as a whole was examined.
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Some Acute Effects of X-Irradiation (LD100) on Plasma and Adrenal Tissue Histamine in Rats

Some Acute Effects of X-Irradiation (LD100) on Plasma and Adrenal Tissue Histamine in Rats

Date: May 1972
Creator: Ferguson, James L.
Description: The effects of a lethal dose (1380 r) of X-irradiation on plasma and adrenal tissue histamine levels of rats were studied. The plasma histamine response was triphasic (increase at 1-3 hours, decrease at 5 and 9 hours and return to control at 24 hours post-irradiation). The adrenal tissue histamine response was found to be biphasic (decrease at 1 to 9 hours and a return to control level at 24 hours post-irradiation).
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A Taxonomic Study of the Family Bacteroidaceae

A Taxonomic Study of the Family Bacteroidaceae

Date: August 1971
Creator: Funderburk, Noel Roger
Description: This study was performed to clarify the taxonomy of the bacteria in the family Bacteroidaceae.
Contributing Partner: UNT Libraries
A Comparative Study of Passive Transfer Mechanisms of Tuberculin and Chemical Contact Delayed Hypersensitivities in the Guiea Pig

A Comparative Study of Passive Transfer Mechanisms of Tuberculin and Chemical Contact Delayed Hypersensitivities in the Guiea Pig

Date: June 1970
Creator: Nunez, William Joseph
Description: This study is concerned with a critical comparison of the passive transfer mechanisms of tuberculin and chemical contact hypersensitivities in the guinea pig by use of a four phase experimental approach.
Contributing Partner: UNT Libraries
Food, Feeding Selectivity, and Ecological Efficiencies of Fundulus notatus (Rafinesque) (Osteichthyes; Cyprinodontidae)

Food, Feeding Selectivity, and Ecological Efficiencies of Fundulus notatus (Rafinesque) (Osteichthyes; Cyprinodontidae)

Date: August 1970
Creator: Atmar, Gerald Legare
Description: This study was made to further define the trophic dynamics of Fundulus notatus by determining its ration composition under natural conditions, measuring feeding selectivity under various laboratory conditions of prey-species composition and availability, and determining the efficiencies with which F. notatus utilizes ingested chironomid larvae.
Contributing Partner: UNT Libraries
Carbon Flux in Reservoir Sediments

Carbon Flux in Reservoir Sediments

Date: May 1973
Creator: Newton, Charles Eugene
Description: The central objective of the study was to fractionate sedimenting organic materials according to their source (allochthonous or autochthonous) and ultimately to determine the degree of biodegradability of contributions from either source with particular reference to activities at the mud-water interface.
Contributing Partner: UNT Libraries