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Molecular-Genetic And Structural Analyses Of The Nifhdkx Proteins Of The Nitrogenase System, Surobhi Lahiri

Theses and Dissertations

The nitrogenase enzyme is the biochemical machiner responsible for the conversion of the largely unavailable nitrogen to the easily assimilable ammonia for living organisms by the process termed as biological nitrogen fixation (BNF). This study was focused on understanding the various structural and functional aspects of the nitrogenase enzyme related to maturation and assembly of the FeMo-cofactor (FeMoco) metallocluster of the MoFe protein (the site for final substrate reduction), development of a dimeric MoFe protein and the structural homology of nitrogenase with other metalloenzymes. This research was specifically directed towards the NifHDKX proteins in which the nifHDK genes are the …

The Osmotic Second Virial Coefficient As A Predictor Of Protein Stability, Kusum S. Verma

Theses and Dissertations

The number of protein containing therapeutic drugs is growing day by day. Lack of proper storage conditions can cause protein degradation or aggregation. The osmotic second virial coefficient, B22, is a thermodynamic parameter, which can predict protein interaction with other proteins and solvent molecules. B22 has been successfully used as predictor of crystallization conditions for a protein in the solution, and in this study an attempt has been made to relate B22 as a predictor of stability of the protein. Static light scattering was used to measure B22 in our studies. B22 and the solubility of three proteins were measured …

The Use Of Dietary Fat Supplementation On Growth, Reproduction And Performance Characteristics Of Replacement Beef Heifers, Alecsandro Rufino Dos Santos

Theses and Dissertations

The purpose of these studies was to evaluate the effects of a dietary fat supplementation on growth, reproduction and performance characteristics of replacement beef heifers reared in different management systems (pasture and dry lot conditions). The objectives were (1) to quantify changes in body composition traits and growth performance of replacement beef heifers fed different levels of fat in the supplemented diet,(2) to determine the reproductive performance of heifers supplemented with dietary fat in either a ryegrass pasture system or a dry lot system, and (3) to determine the value of real-time ultrasound technology (RTU) as an alternative technology to …

Expression And Function Of Alpha3 And Beta2 Neuronal Nicotinic Acetylcholine Receptor Subunits In Hek-293 Cells, Nathan W. Steinhafel

Theses and Dissertations

Single-cell real-time quantitative RT-PCR was used to characterize the mRNA expression of rat neuronal nicotinic acetylcholine receptor (nAChR) subunits α3 and β2 in CA1 hippocampus stratum radiatum and stratum oriens interneurons. α3β2 co-expression was detected in 43% of interneurons analyzed. The nAChR subtype α3β2 was transiently expressed in cells derived from the human embryonic kidney cell line 293 at mRNA levels found in the CA1. The functional properties of α3β2 in HEK-293 cells were characterized by whole-cell patch clamping using acetylcholine (ACh) as an agonist. The kinetics of α3β2 channels were further analyzed by altering the level of α3 DNA …

Brain Stimulation Reward Is Integrated By A Network Of Electrically-Coupled Gaba Neurons, Matthew Brian Lassen

Theses and Dissertations

Although it is well-established that animals will self-stimulate electric current to various diverse brain structures, the neural substrate of brain stimulation reward (BSR) has eluded identification since its discovery more than a half-century ago. We show that GABA neurons in the midbrain, hypothalamus and thalamus express connexin-36 (Cx36) gap junctions and couple electrically with dopamine application or by stimulation of the internal capsule (IC), which also supports self-stimulation. The threshold for responding for self-stimulation of the IC is the threshold for coupling between these GABA neurons, the degree of responding for IC ICSS is proportional to the magnitude of electrical …

Evolution In Neotropical Herpetofauna: Species Boundaries In High Andean Frogs And Evolutionary Genetics In The Lava Lizard Genus Microlophus (Squamata: Tropiduridae): A History Of Colonization And Dispersal, Edgar Benavides

Theses and Dissertations

In this collection of papers I have summarized my investigations into the field of evolutionary genetics and more specifically into patterns of biodiversity and evolutionary processes. The lizards (and frogs) studied here share common features in that they are largely present in unique environments, which are also regions that are biologically understudied. Most of these taxa show high degrees of endemism, interesting natural history characteristics, and each group manifests distinctive adaptations of general evolutionary interest. My work in the genus Telmatobius has been a progressive approach that began in my MS program, and it first focused on alpha taxonomy, morphological …

Analysis Of Near-Infrared Phase Effects On Biometric Iris Data, Brady Roos Stevenson

Theses and Dissertations

The purpose of this research is to ascertain potential iris scan data variations from near infrared waves derived from fluorescent illumination. Prior studies of iris data variances from infrared wave interference of halogen, incandescent, and sunlight with iris cameras suggest that similar changes may exist under near infrared wavelengths from fluorescent light. The concern is that the fluorescent energy emission may interfere with the near infrared detection of an iris camera. An iris camera is used to measure human eye characteristics known as biometrics. If such infrared emission is statistically significant, then it can alter the validity of the iris …

Pilgrimage Narrative: A Pattern For Heavenly Theatre In King Lear, Alexandra Chantal Yvette Mackenzie

Theses and Dissertations

I have always felt personally challenged and invigorated by one line in Peter Brook's canonical text The Empty Stage: “if the need for a true contact with a sacred invisibility through the theatre still exists, then all possible vehicles must be re-examined" (Brook 54). This thesis will endeavour to suggest and explore heavenly theatre, one possible vehicle to find that sacred invisibility. I will argue that heavenly theatre encompasses Peter Brook's understanding of holy theatre, but is more specific and tied to the manifestation of deity in the form of the Holy Spirit as understood and defined within my personal …

Impact Of Wastewater Reuse In Burlington County On Surface Water Quality And Adjacent Wetlands, Crystal L. Mattson

Theses and Dissertations

This study was conducted to assess potential ecological impacts from application of treated wastewater effluent. Indian Springs Golf Course is currently irrigated with reclaimed wastewater. Grab water samples were collected from three (3) ponds located on the golf course over the course of a year and were analyzed for nitrate-nitrogen, total phosphorus, organics, and bacteria. A second golf course, Medford Lakes Country Club is currently irrigated with groundwater. Grab water samples were collected from both locations and analyzed for nutrients and bacteria for comparison purposes.

Results of sample analyses indicate that detriment to the quality of surface water at the …

Forage Adaptability Trials For Forage And Seed Production In Bolivia; Effect Of 5 Herbicides On 7 Native Utah Forbs, Joshua C. Voss

Theses and Dissertations

The harsh environmental and poor economic conditions of the Bolivian Altiplano require intervention to assist many of those that live there to become economically self-sufficient. We attempted to find introduced dry season reserve forage grasses that could produce enough biomass to be useful as feed for livestock, and that could also produce enough seed to distribute to farmers. While some of the grasses produced reasonable amounts of biomass, none produced seed in quantities that would be even close to being economically viable. The most likely cause of this is that the timing of resources that the grasses need to flower …

Synthesis And Optical Properties Of Four Oligothiophene-Ruthenium Complexes And Synthesis Of A Bidentate Ligand For C-F Bond Activation, Joseph S. Bair

Theses and Dissertations

Photovoltaic cells and fluorescence sensing are two important areas of research in chemistry. The combination of photon-activated electron donors with electron acceptors provides a strong platform for the study of optical devices. A series of four oligothiophene-ruthenium complexes has been synthesized. Variation in oligothiophene length and bipyridine substitution allowed comparison of these variables on electronic properties. The longer oligothiophenes display lower energy absorption and emission compared to the shorter ones. Aromatic conjugation appears more complete with para-, rather than meta-, substitution. Oligothiophenes and Ru(bpy)32+ are highly fluorescent individually, but fluorescence is quenched when connected. Bonds of carbon to fluorine are …

Development Of Polymer Monoliths For The Analysis Of Peptides And Proteins, Binghe Gu

Theses and Dissertations

Several novel polymer monoliths for the analysis of peptides and proteins were synthesized using polyethylene glycol diacrylate (PEGDA) as crosslinker. Photo-initiated copolymerization of polyethylene glycol methyl ether acrylate and PEGDA yielded an inert monolith that could be used for size exclusion liquid chromatography of peptides and proteins. This macroscopically uniform monolith did not shrink or swell in either water or tetrahydrofuran. More importantly, it was found to resist adsorption of both acidic and basic proteins in aqueous buffer without any organic solvent additives. A strong cation-exchange polymer monolith was synthesized by copolymerization of 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) and PEGDA. A ternary …

The Role Of Wnt Signaling In Development Of The Ophthalmic Trigeminal Placode., Rhonda Nicole Lassiter

Theses and Dissertations

Cranial placodes are ectodermal regions that contribute extensively to the vertebrate peripheral nervous system. The development of the ophthalmic trigeminal (opV) placode, which gives rise only to sensory neurons of the ophthalmic lobe of the trigeminal ganglion, is a well-studied model of sensory neuron development. While key differentiation processes have been characterized at the tissue and cellular levels, the molecules governing opV placode development have not been well described. This study identifies the canonical Wnt signaling pathway as a regulator of opV trigeminal placode development. Introducing dominant-negative TCF and dominant-active β-catenin expression constructs by in ovo electroporation, we have manipulated …

Phylogenetics Of North American Psoraleeae (Leguminosae): Rates And Dates In A Recent, Rapid Radiation, Ashley N. Egan

Theses and Dissertations

The scientific discipline of phylogenetics involves understanding the diversity of life in the context of history. Technological advances in molecular biology and computational power have created an exponential increase in the number and kind of phylogenetic studies, allowing exploration of all manner of questions concerning the evolutionary history of a group. This dissertation research is focused on phylogenetic theory and applying these methods to the plant tribe Psoraleeae (Leguminosae; Fabaceae) with an emphasis on North American (NAm) members. First, theory of phylogeny estimation is explored in a review chapter focusing on strengths and weaknesses of phylogenetic methodology. Second, methods are …

Computationally Modeling The Effects Of Surface Roughness On Soft X-Ray Multilayer Reflectors, Jedediah Edward Jensen Johnson

Theses and Dissertations

Electromagnetic scattering from a rough two dimensional homogeneous scatterer has been computationally modeled. The scatterer is intended to simulate reflection from a two interface multilayer. The rough scatterer was created from Gaussian random points centered about an ideal interface. The points were connected with a third order spline interpolant which accounts for correlation between neighboring surface atoms. The scalar electric field integral equation (EFIE) and magnetic field integral equation (MFIE) were solved using the Nystrom method to obtain the reflected intensity as a function of observation angle. Verification of the accuracy of the code was obtained by means of comparison …

Effects Of Aspartame Consumption On Cognitive Function, Fang Ye

Theses and Dissertations

The FDA estimates that 35% of Americans regularly consume aspartame, an artificial sweetener used in diet drinks and other sugar-free food items. Some anecdotal reports indicate the substance has been associated with health, behavioral, and cognitive concerns. The FDA and other regulatory agencies indicate it is safe for use up to 50mg/kg/day. They further advise individuals with metabolic phenylalanine disorders not to consume this product. This conflicting advice has caused confusion for consumers and practioners. Therefore, the purpose of this study was to examine the effects of aspartame consumption on cognitive functioning of healthy adults.

Orem's theory of Self-Care guided …

Influential Factors Affecting The Career Success Of Professional Northern Plains Native American Males: A Qualitative Study, Adam J. Guilmino

Theses and Dissertations

The purpose of this study was to better understand successful vocational experiences among Northern Plains Native American males. Most studies completed up to this point have approached the issue of Native American career exploration from a problem-based perspective. This study used a Consensual Qualitative Research (CQR) methodology to examine the experiences of Native Americans who have been nominated by their tribal community as career successful members of their community.

Eight male members of two North Dakota Native American tribes were interviewed using semi-structured qualitative interview protocol. Interviews were transcribed and analyzed for domains and categories. Eight domains emerged from the …

Development And Validation Of The Coping, Alcohol/Drugs, And Trauma Scale (Cats), Patricia J. Hunter

Theses and Dissertations

This study was designed to develop and investigate the validity of a coping scale (Coping, Alcohol/Drugs, and Trauma Scale; CATS), which could be used to predict problematic alcohol and drug (AOD) use patterns among college women, based upon historical stressors. It was predicted that the CATS would have strong convergent validity with the Michigan Alcohol Screening Test-Revised (MAST-R), moderately strong convergent validity with the Coping Response Inventory - Avoidant Scale (CRI- Avoidant), and moderate convergent validity with the Traumatic Events Questionnaire (TEQ). Additionally, the CATS was expected to have strong correlations to binge drinking as measured by the Khavari Alcohol …

Funny Ha-Ha Or Funny Strange: The Structure And Meaning Of Laughter In Conversation, Linda Houts-Smith

Theses and Dissertations

Although laughter has been studied for centuries, the work has occurred in several different fields, and the lack of an interdisciplinary approach has hindered the integration of results. Work in philosophy has focused on why we laugh but has lacked a basis in empirical data, resulting in ungrounded theories. Studies in neuroscience and linguistics rest on empirical data, but stop short of a full description of the phenomenon of laughter, focusing on when and how we laugh, but not why. This study seeks to describe the phenomenon of laughter more fully, to describe both the nature of the laughable and …

Development Of Methods For The Study Of Phosphoproteins, Zhaoyuan Chen

Theses and Dissertations

Characterization of phosphoproteins-including detection, identification of phosphoproteins and identification of phosphorylation sites-is mostly done with radiolabeling and proteomic techniques. Three main topics related to phosphoprotein characterization are included in this dissertation. First, large-scale characterization of the CHO (Chinese hamster ovary) cell phosphoproteome was done using two dimensional gel electrophoresis (2DE) separation, visualization of phosphoproteins by radiolabeling or a phosphoprotein specific dye, followed by MALDI-TOF identification. Because radiolabeling of phosphoproteins is very sensitive and straightforward to quantify, such analysis can give a clear picture of the relative phosphosphorylation of proteins present in a sample. But there are also limitations to this …

Once Upon A Time In A Single-Parent Family: Father And Daughter Relationships In Disney's The Little Mermaid And Beauty And The Beast, Ashli A. Sharp

Theses and Dissertations

Fairy tales are adapted to fit the needs of each generation, reflecting the unique challenges of that society. In the 1980s and 1990s of the United States, issues of what constituted a family circulated as divorce increased and fatherhood was debated. At this time, Disney released two animated films featuring a father and daughter: The Little Mermaid and Beauty and the Beast. Both films are adaptations of fairy tales, and they incorporate changes that specifically reflect concerns of the United States in the late-twentieth century. In the original narrative of "The Little Mermaid" the heroine is primarily raised by her …

North Dakota Dual Credit: Initial Impact 1997-2004, Anita K. Decker

Theses and Dissertations

The purpose of this study was to investigate the impact of enrollment in North Dakota’s dual credit program on the students who had been enrolled from Fall 1997 through Spring 2004. Participants are identified by gender, by year in school, by courses taken for dual credit, and by high school size. Analysis of post-high school college entry data by matriculation, graduation, and grade point average are included.

Dual credit students took over 12,000 courses from the eleven public colleges in the North Dakota University System and from five nonpublic or out-of-state colleges. Students were divided between seniors, who took 9836 …

Predictors Of Change In Health Care Use After Marital And Family Therapy, Scott H. Payne

Theses and Dissertations

The cost of health care continues to increase. Based on the biopsychosocial model of heath care, it has been shown that the treatment of psychological and social problems can have a cost offset effect on the cost of medical care. While this offset effect has been shown in an MFT population, there are no known studies that have looked at predictors of the change in medical use by those that receive marital and family therapy. This study looked at psychological and social measures of individuals who received marital and family therapy. These measures were evaluated based on the change from …

The Influence Of Membrane Lipid Order On Cell Shape And Microvesiculation In Human Erythrocytes, Laurie Jackson Gonzalez

Theses and Dissertations

Exposure of human erythrocytes to elevated intracellular calcium causes alterations in cell shape and stimulates shedding of the cell membrane in the form of microvesicles. We hypothesized that both the shape transition and microvesiculation are influenced by microscopic membrane physical properties such as lipid order. To test this hypothesis, membrane properties were manipulated by varying the experimental temperature, membrane cholesterol content, and the internal ionic environment. Changes in membrane order were assessed using steady-state fluorescence spectroscopy with an environment-sensitive probe, laurdan. Our observations led us to the following conclusions: 1) the modest temperature dependence of membrane structure observed with laurdan …

Fgf4 And Wnt5a/Pcp Signaling Promote Limb Outgrowth By Polarizing Limb Mesenchyme, Keri Lynn Low

Theses and Dissertations

The focus of this study was to elucidate the molecular and cellular mechanisms whereby fibroblast growth factors (FGFs) mediate outgrowth of the limb. Specifically, we examined the epistatic relationship between FGF and Wnt/Planar cell polarity (PCP) signaling in establishing cell polarity as a mechanism for outgrowth. By implanting beads into embryonic limbs and lateral plate mesoderm, we established that FGF activates Wnt5a in a gradient fashion. Once it was established that Wnt5a was expressed at the right time and place to turn on PCP signaling, we investigated the ability of Wnt5a to influence cell migration and/or cell polarity. Our analysis …

Effects Of Cheatgrass Control On Wyoming Big Sagebrush In Southeastern Utah, Daniel Blaine Eddington

Theses and Dissertations

Critical mule deer (Odocoileus hemionus) winter ranges in southeastern Utah dominated by Wyoming big sagebrush (Artemisia tridentata var. wyomingensis [Beetle and A. Young] Welsh) have developed dense cheatgrass (Bromus tectorum L.) understories. These communities are currently characterized by predominately mature to decadent stands of sagebrush with few perennial grasses and forbs. Sagebrush seedlings and perennial grasses compete for limited resources with annual grasses and forbs. To determine the affects of cheatgrass control on sagebrush growth and reproductive characteristics, imazapic (PLATEAU®, AC 263,222) herbicide was sprayed at 438.5 ml/ha with water and methylated seed oil during active fall growth of cheatgrass …

A Comparison Of Microarray Analyses: A Mixed Models Approach Versus The Significance Analysis Of Microarrays, Nathan Wallace Stephens

Theses and Dissertations

DNA microarrays are a relatively new technology for assessing the expression levels of thousands of genes simultaneously. Researchers hope to find genes that are differentially expressed by hybridizing cDNA from known treatment sources with various genes spotted on the microarrays. The large number of tests involved in analyzing microarrays has raised new questions in multiple testing. Several approaches for identifying differentially expressed genes have been proposed. This paper considers two: (1) a mixed models approach, and (2) the Signiffcance Analysis of Microarrays.

A New Spectroscopic Method For The Non-Destructive Characterization Of Weathering Damage In Plastics, Andrew Robert George

Theses and Dissertations

The weathering of plastics and composites is a problem because of the loss of both physical and mechanical properties that it causes in these materials. But this weathering effect has been difficult, and in some cases, impossible to characterize without the destruction of the plastic or composite part. Clearly a rapid, reliable, and non-destructive test for the extent of the weathering damage is critically needed. A recent problem that arose at Superyacht Solutions, a boat repair company in Australia, required a solution to just this problem. Such a test was developed for Superyacht Solutions, and is being applied across a …

The Role Of Boron In The Regulation Of Inflammation: Studies In Vivo And In Vitro, Kelly Ann Durick

Theses and Dissertations

I demonstrated here that the presence of physiological amounts of boron was able to prevent the onset of and ameliorate ongoing collagen-induced arthritis (CIA). I also show a mechanism for boron's anti-inflammatory properties, in that boron was able to down regulate a number of pro-inflammatory mediators, all of which are under transcriptional control of NF-κB. Boron-supplemented diets, 2.0 mg B/kg and 12 mg B/kg, rendered CIA susceptible mice significantly more resistant to the onset of clinical arthritis, compared to mice fed boron-deficient chow, or commercial rodent chow. Dietary boron supplementation was also shown to prevent the onset of experimental autoimmune …

Laboratory -Induced Aggression Among Participants With And Without A History Of Alcohol -Related Aggression, Matthew D. Bailly

Theses and Dissertations

The effects of alcohol-related and mixed alcohol and non-alcohol-related histories of aggression on aggressive responding in the laboratory were investigated using the Point Subtraction Aggression Paradigm (PSAP). Forty-five male college students were selected for participation in the present study using a questionnaire consisting of modified items from the Buss-Durkee Hostility Inventory (BDHI; Buss & Durkee, 1957) and Overt Aggression Scale (OAS; Yudofsky et al., 1986) that allowed for assignment to an alcohol-related, mixed, or no history of aggression control condition. Participants performed four 25-minute PSAP sessions in sequence during one laboratory visit. The short version of the Minnesota Multiphasic Personality …