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Effects Of Altered Superoxide Dismutase Expression On Age-Related Functional Declines And Survival In Drosophila, Ian Martin

Theses and Dissertations

Most organisms experience progressive declines in physiological function as they age. A number of studies in a variety of species support a strong link between oxidative damage, age-related functional declines and life span determination. Here, manipulating the expression levels of superoxide dismutase (SOD) isoenzymes SOD1 and SOD2, resulted in altered functional senescence and survival characteristics in Drosophila. Overexpression of cytosolic Sod1 using the yeast GAL4/UAS system conferred a 30-34% increase in mean life span and resulted in an attenuated senescence of odor avoidance behavior in aging flies. Tissue-specific Sod1 overexpression selectively in the nervous system or muscle failed to reproduce …

The Effect Of Nacl On Akinete Differentiation In The Cyanobacterium Nostoc Punctiforme, Jonathan Heekin

Theses and Dissertations

Nostoc punctiforme is a nitrogen-fixing, symbiotic/free-living cyanobacterium. There has been a great deal of research conducted on the genomic nature of N. punctiforme as it pertains to its ecologically important role in the nitrogen cycle in varied environments around the world. My study concentrated on the dormant cell type known as the akinete. Increasing concentrations of NaCl were used to follow the growth phases from germination to akinete formation (lag phase-logarithmic growth phase-stationary phase). I found that increased salt concentrations caused N. punctiforme to form akinetes faster when compared to the control. Germination rates were not greatly increased or shortened …

Electrical Behavior Of Non-Aqueous Formulations: Role Of Electrostatic Interactions In Pressurized Metered Dose Inhalers (Pmdis), Reshma Kotian

Theses and Dissertations

Aerosol electrostatics is an important property of pharmaceutical aerosols. The electrostatic properties of pMDI aerosols have been shown to be a function of both formulation and packaging components. The modified ELPI enables measurement of aerosol charge as a function of particle size, and the simultaneous determination of the mass distribution using chemical analysis. However, in order to fully assess the cause and effects of aerosol electrostatics in terms of its biological and regulatory implications, it is necessary to understand the basic charging mechanisms inside the pMDI formulation.

Electrical resistivity and zeta potential measurements confirmed the presence of charged species within …

Inflammatory Regulation Of Cysteine Cathepsins, Blaine Creasy

Theses and Dissertations

Cysteine cathepsins B, L and S are endosomal/lysosomal proteases that participate in numerous physiological systems. Cathepsin expression and activity are altered during various inflammatory diseases, including rheumatoid arthritis, atherosclerosis, neurodegenerative diseases and cancers. Early immune responses to microbial pathogens are mediated by pattern-recognition receptors, including Toll-like receptors (TLR). Signaling through TLR causes cell activation and release of inflammatory mediators, which can contribute to the severity of chronic inflammatory diseases. The impact of TLR cell activation on cathepsins B, L and S activities was investigated using live-cell enzymatic assays. Individual ligands of TLR4, TLR2 and TLR3 increased intracellular activities of the …

Effects Of Hemoglobin-Based Oxygen Carriers On The Vasoactivity Of The Spinotrapezius Muscle Of The Rat, Pete Meliagros

Theses and Dissertations

Hemoglobin-based oxygen carriers (HBOCs) offer a safe, more plentiful and long term alternate to blood banks. However, they have been found to increase blood pressure which can be attributed to an increase in total peripheral resistance (TPR). Lumenal nitric oxide (NO) scavenging by these HBOCs seems to be responsible for this hypertensive effect. In addition, it is believed that hemoglobin (Hb) tetramers and dimers may extravasate and consume additional nitric oxide in the perivascular and interstitial space. The purpose of the present study was to elucidate the role of NO scavenging and to confirm extravasation as a contributor to HBOC …

The Ecology Of Fear: Oviposition And Colonization In Aquatic Systems, Leeanna Pletcher

Theses and Dissertations

Amphibians and aquatic invertebrates have complex life histories that link aquatic and terrestrial food webs. It has been suggested that amphibian reproduction is an important source of carbon to some aquatic systems. This process of energy flow may be shaped by shifts in habitat selection in response to predators. We hypothesized that predators decrease colonization and oviposition of prey, reducing active inputs. Thus predation risk is expected to shift the relative amounts of active and passive subsidies. We manipulated the presence of fish predators in aquatic mesocosms. Results suggest hylid treefrog eggs and hydrophilid beetles were less abundant in predator …

Mechanistic Studies On The Electrochemistry Of Glutathione And Homocysteine, Olufemi Oyesanya

Theses and Dissertations

This research work has investigated the electrochemistry of glutathione (GSH)and homocysteine (HCSH) in order to develop sensors for these biological thiols.Ru(bpy)₃³⁺ and IrCl₆²⁻ have been used as mediators for the electrooxidation of GSH andHCSH because direct oxidation of these thiols is slow at most conventional electrodes.The electrochemical detection of GSH and HCSH has been pursued because of their biological roles.

Concerted proton electron transfer (CPET) and stepwise proton electron transfer(PT/ET) pathways have been observed in the electrooxidation of GSH and HCSH.Oxidation of GSH by Ru(bpy)₃³⁺ carried out in deuterated and undeuterated buffered (pH= pD …

Expression Of Nicotinic Acetylcholine Receptor Mrna As A Function Of Age In Whole Hippocampus Preparations From Wistar Rats, Kasey C. Welch

Theses and Dissertations

Whole hippocampus preparations, isolated bilaterally, from untreated Wistar rats at various ages (10-90 days old) were analyzed for the mRNA expression of the alpha 2, alpha 3, alpha 4, alpha 5, alpha 7, beta 2, beta 3, and beta 4 neuronal nicotinic acetylcholine receptor subunits. To do so, RNA was isolated from acutely isolated hippocampal samples, converted to cDNA by means of a reverse transcription reaction, then analyzed with quantitative real-time PCR to determine the relative levels of the mRNAs the cells were expressing at the age when the samples were obtained. The relative expression of the levels of RNA …

Characterization Of Histone Acetylation During Sv40 Transcription, Lata Balakrishnan

Theses and Dissertations

Compaction of DNA by histone proteins helps to package the DNA into the nucleus at the expense of acting as a bather to biological processes that require access to the DNA. Addition and removal of acetyl groups from the histone tails with the help of enzymes known as histone acetyltransferases (HATs) and histone deacetylases (HDACs) appear to play a critical role in maintaining the structure of chromosomes and the regulation of gene expression. In order to better understand the role of histone hyperacetylation in the regulation of gene expression I studied histone hyperacetylation in Simian Virus 40 (SV40) chromosomes during …

Toward A New Perspective In Literary Criticism: Transgenerational Psychoanalysis And Anasemic Procedures, Gustav Arnold

Theses and Dissertations

This dissertation—Toward a New Perspective in Literary Criticism: Transgenerational Psychoanalysis and Anasemic Procedures"—is a contribution to literary criticism. It offers a new perspective in psychoanalytical criticism on how characters in literary narratives can be interpreted. By examining key concepts in psychoanalysis, which have been used in the humanities for decades, the present inquiry draws on transgenerational psychology, as elaborated by German and French theorists, and anasemic interpretations generated by M. Torok and N. Abraham's psychoanalytical approach. Based on the assumption that a character's psychic life is determined by factors that cannot be confined to intrapsychic processes alone, the transgenerational perspective …

Altered Signaling By Fibronectin Fragments Creates A Potent Chondrolytic State, Lei Ding

Theses and Dissertations

It has been shown that fibronectin fragments (Fn-fs) greatly augment cartilage proteoglycan (PG) depletion by up-regulating matrix metalloproteinases (MMPs) and catabolic cytokines. The activities of three different Fn-fs have been studied: an amino terminal 29-kDa which is most potent with a weak affinity to the α5β1, integrin, the receptor for native fibronetin (Fn); a 50-kDa gelatin-binding Fn-f with no known interaction with Fn receptor; and a 140-kDa Fn-f which is the least potent and has a RGDS sequence which can bind to the α5β1 integrin. Confocal studies showed that Fn-fs caused diffusion of α5β 1 integrin clusters which were seen …

Regulation Of Pro-Inflammatory Responses By Ligands Of The Nuclear Receptor Pparγ, Andrew P. Woster

Theses and Dissertations

Inflammation-related neurotoxicity is evident in a number of different models neurodegenerative conditions, including Alzheimer's and Parkinson's diseases, Multiple Sclerosis, and HIV-associated dementia. Peroxisome proliferator-activated receptor gamma (PPARγ) agonists inhibit a number of select pro-inflammatory changes in models of CNS and systemic inflammation. Recent reports suggest that these anti-inflammatory effects are due to mechanisms other than canonical nuclear receptor-mediated transcriptional alteration. Results reported here demonstrate that rosiglitazone, a PPARγ-activating thiazolidinedione, decreases tumor necrosis factor α (TNFα) secretion in both primary microglia and the monocytic cell line, THP-1. Cells were pretreated with various PPARγ ligands, including rosiglitazone, prior to stimulation with lipopolysaccharide …

Light Induced Changes In The Photoreceptor Outer Segments, Vikram Palamalai

Theses and Dissertations

Light induced retinal degeneration in animals has been used to study human retinal degenerative disorders. Apoptosis is the final common pathway for photoreceptor degeneration in both the experimental model and human disease but the mechanism is unknown. Oxidative stress plays a role because antioxidants have been shown to be protective against experimental degeneration. Inhibitors of nitric oxide synthases (NOS) are also protective suggesting a role for nitric oxide. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) a key enzyme in glycolysis was identified as one of the proteins undergoing significant nitration in our studies on light induced retinal degeneration. This study focuses on the changes …

Effects Of Predation Risk, Density And Disease On Energy Efficiency In A Larval Anuran, Sarah Crane

Theses and Dissertations

Predation, density and disease affect behavior, morphology and growth. There is a lack of information on how these changes relate to efficiency of energy transfer in anuran larvae, although previous studies suggest that predation should decrease and competition should increase efficiency. Using a 2 x 2 factorial design, we manipulated predation presence and larval density to test how predation risk and density affect energy efficiency. During the experiment, approximately half of the tadpoles were infected by an unknown disease. Neither predation risk nor density affected assimilation or growth efficiency, despite changes in growth and development. Disease, however, decreased gut length …

A Longitudinal Examination Of The Influences Of Family Processes And Demographic Variables On Adolescent Weight, Jessica Lee Price

Theses and Dissertations

Nationally representative studies estimate that almost one in five adolescents in the United States is overweight. This is a major concern for individuals' physical and psychological health and the overall economy in terms of health care costs and loss of productivity. The approach of this study was to understand adolescent overweight as influenced by family processes including: parent-adolescent relationship, monitoring or parental knowledge, control, family meals, and parenting styles. Race, sex, family structure, income, and mother Body Mass Index (BMI) were also included. A sub-sample of 4,688 adolescents from the National Longitudinal Survey of Youth 1997 was used to address …

Biological Functions Of The Novel Lysophosphatidic Acid (Lpa) Receptor, Lpa4/P2y9/Gpr23, Peilun Lee

Theses and Dissertations

Lysophosphatidic acid (LPA), a naturally occurring phospholipid present in serum and malignant effusions, elicits diverse biological functions through binding and activating specific cell surface G-protein coupled receptors. In addition to the conventional LPA1/Edg2, LPA2/Edg4 and LPA3/Edg7 receptors of the endothelial differentiation gene (Edg) family, LPA4/p2y9/GPR23 of the purinergic receptor family and the related LPA5/GPR92 and LPA6/p2y5 have been identified as novel LPA receptors. These newly identified LPA receptors are structurally distant from the Edg LPA1-3 receptors and couple to Gq, G12/13 and probably Gs subunits. However, the roles of the LPA4-6 receptors in LPA signal transduction and physiology are poorly …

Designing Non-Saccharide Heparin/Heparan Sulfate Mimics, Arjun Raghuraman

Theses and Dissertations

Glycosaminoglycans (GAGs) are complex biopolymers that play important roles in inflammation, coagulation, angiogenesis, cell adhesion and viral invasion by interacting with several different proteins.1,2 Structurally, GAGs are built up of several different sulfated disaccharide units.3 Specific GAG sequences that uniquely recognize their cognate proteins exist. Such specificity typically arises from the binding of unique sulfation patterns on the linear GAG chain to highly electropositive protein domains. Thus, these highly charged, sulfated biopolymers potentially represent a new class of therapeutics. Yet, the major stumbling block to the development to these agents is their extremely complicated and tedious chemical synthesis. We hypothesized …

Increasing Dogma Scaling Through Clustering, Nathan Hyrum Ekstrom

Theses and Dissertations

DOGMA is a distributed computing architecture developed at Brigham Young University. It makes use of idle computers to provide additional computing resources to applications, similar to Seti@home. DOGMA's ability to scale to large numbers of computers is hindered by its strict client-server architecture. Recent research with DOGMA has shown that introducing localized peer-to-peer downloading abilities enhances DOGMA's performance while reducing the amount of network and server usage. This thesis proposes to further extend the peer-to-peer abilities of DOGMA to include peering client server communication by creating dynamic clusters of clients. The client clusters aggregate their communication with only one client …

Health Risks And Academic Performance: Implications For College Students, Faculty And Administration, Mary F.D. Larson

Theses and Dissertations

In order to enter post-secondary education, a student must have demonstrated the ability to do reasonably well in an academic environment. Yet, many students end up stopping out or even dropping out of college, and oftentimes it is due to academic underachievement. There are many reasons why students do not succeed and one of those reasons is health.

The purpose of this study was to examine relationships between physical health, mental health, stressors, sleep, and substance use and abuse variables and academic performance in a sample of 503 students from a small private liberal arts college in the Midwest. The …

Higher Education Policy Punctuations: An Assessment Of Media Attention And Congressional Oversight, Dean Lefor

Theses and Dissertations

Congressional oversight of higher education is vital part of the policy process. However, a compressive study regarding the relationship between higher education oversight and attention has not been conducted. By utilizing McCubbins and Swartz’s Police Patrol and Fire Alarm Oversight Dichotomy, this experiment was able to discover that a relationship exists between fire alarm oversight and the amount of public attention in the higher education policy process.

Congressional hearings in higher education were broken into three sections over a 58-year period. Each section was divided by major policy punctuations such as the Higher Education Act of 1965 and the 1980 …

Using Hierarchical Temporal Memory For Detecting Anomalous Network Activity, Gerod M. Bonhoff

Theses and Dissertations

This thesis explores the nature of cyberspace and forms an argument for it as an intangible world. This research is motivated by the notion of creating intelligently autonomous cybercraft to reside in that environment and maintain domain superiority. Specifically, this paper offers 7 challenges associated with development of intelligent, autonomous cybercraft. The primary focus is an analysis of the claims of a machine learning language called Hierarchical Temporal Memory (HTM). In particular, HTM theory claims to facilitate intelligence in machines via accurate predictions. It further claims to be able to make accurate predictions of unusual worlds, like cyberspace. The research …

What Constitutes An Act Of War In Cyberspace, Kelli S. Kinley

Theses and Dissertations

In December 2005 a new mission statement was released by the Air Force Leadership, "to deliver sovereign options for the defense of the United States of America and its global interests...to fly and fight in Air, Space and Cyberspace." (Wynne & Mosley, 2005) With the stand up of the AFCYBER command and the use of cyberspace to carry out our daily mission the U.S. needs to have a clear understanding of what war in cyberspace looks like and what the laws are governing war in cyberspace. This research and it's resulting data analysis is intended to provide a better understanding …

Neutron Detection Utilizing Gadolinium Doped Hafnium Oxide Films, Bryan D. Blasy

Theses and Dissertations

Gadolinium (Gd) doped hafnium oxide (HfO₂) was deposited onto a silicon substrate using pulsed laser deposition. Synchrotron radiation was used to perform Gd L3-edge extended X-ray absorption fine structure (EXAFS) measurements on 3%, 10%, and 15% doped HfO₂ samples. The interatomic distances determined from Fourier transformation and fitting the data show Gd occupying the hafnium site in the HfO₂ lattice, there was no clustering of Gd atoms, and the Gd ion retains monoclinic local symmetery for all levels of doping. Current as a function of voltage experiments identified the films as having poor diode characteristics with …

An Evaluation And Implementation Guide For Current Groundwater Mass Flux Measurement Practices, Jack G. Wheeldon Iii

Theses and Dissertations

Contaminant mass flux is an important parameter needed for decision making at sites with contaminated groundwater. New and potentially better methods for measuring mass flux are emerging. This study looks at the conventional transect method (TM), and the newer passive flux meter (PFM), modified integral pump test (MIPT), and tandem circulating well (TCW) methods. In order to facilitate transfer and application of these innovative technologies, it is essential that potential technology users have access to credible information that addresses technology capabilities, limitations, and costs. This study provides such information on each of the methods by reviewing implementation practices and comparing …

The Role Of Perceptions Of Female Administrators Regarding The Gender Regimes In Urban Co-Educational Secondary Schools In Uganda, Frances Naluwemba

Theses and Dissertations

Leaders and policy makers in Uganda developed a national strategy of placing female administrators in traditionally male-dominated coeducational secondary schools in the belief that their vision would promote equitable education by changing gender regimes that play in schools. Gender regimes are patterns of gender arrangements that could disadvantage the education of boys or girls (Connell, 2002). The purpose of this study was to discover if female administrators perceived and had developed strategies to change gender regimes in their schools. Participants were 13 female administrators of government-supported coeducational mixed/day secondary schools in Kampala and Wakiso urban districts. Participants ranged in age …

Nano-Mechanical Properties Of Heat Inactivated Bacillus Anthracis And Bacillus Thuringiensis Spores, Jessica L. Poindexter

Theses and Dissertations

B. thuringiensis spores must have similar properties to B. anthracis spores to be a good simulant in counter-proliferation studies. In particular, they must behave in a similar way when exposed to high temperatures for short periods of time as would be caused by an explosion. This research project compares surface elasticities for four different spore sample types, B. anthracis spores, heat inactivated B. anthracis spores, B. thuringiensis spores, and heat inactivated B. thuringiensis spores. Heat inactivated spores were exposed to a temperature just high enough that no spores were observed to germinate. Elasticity values for the spore surfaces were determined …

Three Models Of Anthrax Toxin Effects On The Map-Kinase Pathway And Macrophage Survival, Daniel J. Schneider

Theses and Dissertations

Lethal factor (LF), a component of anthrax toxin, is the primary virulence factor that allows Bacillus anthracis to evade the immune response by blocking the activation of mitogen-activated protein kinase (MAPK) enzymes. This research modifies three published MAPK models to reflect this signal inhibition and to estimate a first-order reaction rate by fitting the models to published viability data for two macrophage cell lines cultured with the LF-producing Bacillus anthracis-Vollum1B strain. One model appears to be ill-suited for this purpose because not all relevant MAPK components could be integrated into the inhibition equations. Despite different underlying parameters and values, the …

Estimation Of The Number Of Microbial Species Comprising A Population, Melanie R. Slattery

Theses and Dissertations

The purpose of this research was to evaluate the appropriateness of using non-parametric estimators, specifically the Chao1, ACES, and Jackknife methods, for estimation of the number of unique species comprising a population. It goes on to develop a parametric method for the above stated problem. This research consisted of creating diverse populations, with known numbers of species, and applying the aforementioned non-parametric and parametric methods to samples drawn from the constructed populations. The parametric fitting of several different distributions to the sample data, including the lognormal, gamma, and Weibull was considered. Both types of methodologies were then applied to sample …

Micro-Etched Platforms For Thermal Inactivation Of Bacillus Anthracis And Bacillus Thuringiensis Spores, Leslie S. Hawkins

Theses and Dissertations

This research developed and applied microlithography techniques to etch microscope slide platforms in order to measure thermal inactivation of Bacillus thuringiensis and Bacillus anthracis spores, two closely related Bacillus species. B.t. is widely used as a surrogate for B.a. in response studies and in some field studies. This work addressed the previously identified problem of measuring both spore growth and spore thermal kill threshold using the traditional method of spreading a diluted spore solution on a plate. The micro-etched platforms forced spore separation thereby preventing neighbor growth from obscuring germination and initial vegetative growth measurements using a microscope. The technique …

Hidden Village (42sa2112): A Basket Maker Iii Community In Montezuma Canyon, Utah, Donald G. Montoya

Theses and Dissertations

ABSTRACT This thesis focuses on the Basketmaker III period of the Ancestral Puebloan culture commonly known as the Anasazi, which means ‘ancient stranger’ or ‘ancient enemy’ in the Navajo language, or as preferred by the Hopi; "Hisatsinom" for "The Ones Who Came Before." I use the terms Anasazi and Ancestral Puebloan interchangeably in this study. My particular focus concentrates on a Basketmaker III settlement (42Sa2112 – Hidden Village) in Montezuma Canyon in southeastern Utah. My thesis presents data and an interpretive hypothesis that village formation and complex social organization emerged earlier than most standard texts (Plog 1997) assume. Analysis of …