Digital Commons Network^™

Silver-Based Microbial Check Valve For Spacecraft Potable Water Systems, Tanner Burns

Chemical Engineering Undergraduate Honors Theses

As human space exploration increases, the development of a more efficient potable water treatment system suited for spacecraft becomes crucial. This Waste-management Education Research Consortium (WERC) challenge was designed to explore the viability of microbial control through the utilization of silver ions as a biocide for possible integration into the Tranquility Node 3 water purification system aboard the International Space Station (ISS). Current systems using iodine risk causing hyperthyroidism from overexposure; however, silver can be safely ingested without this side effect. After researching silver delivery methods including electrochemical ion production, controlled release, or a combination of the two, our team …

The Social Construction Of Black Fatherhood In Responsible Fatherhood Policies, Azaliah B. Israel

Graduate Theses and Dissertations

Responsible fatherhood legislation bridges the gap between two explicit family policies in order to serve fathers: The Personal Responsibility and Work Opportunity Reconciliation Act (PRWORA) of 1996 and the Child Support Enforcement Act of 1975. Historically, these two polices have been racialized and discourse surrounding them may contribute to negative cultural formula stories about the primary targets of responsible fatherhood programs: low-income Black fathers.

The first article addresses the question of whether and how congressional discourse disrupts or legitimizes negative cultural formula stories about Black fatherhood. This study examines congressional discourse during hearings on fatherhood legislation. Members of congress legitimized …

The River Gave And The River Hath Taken Away: How The Arkansas River Shaped The Course Of Arkansas History, Edward N. Andrus

Graduate Theses and Dissertations

The Arkansas River molded the history of Arkansas. It also shaped human to human interactions and human relationships with the physical environment. Since humans first encountered the river their lives have been influenced by it. The river played a significant role in creating the environmental conditions that contributed to a specific existence within the river valley. It affected what types of flora and fauna existed, the quality of the soil, and the climate. The river was a vital component in the evolution of the cultures and societies that developed in the river valley. Conversely, humans affected the river. The ways …

Exploring Convergence Of Snake Skin-Inspired Texture Designs And Additive Manufacturing For Mechanical Traction, Catherine Sue Tiner

Graduate Theses and Dissertations

This research focuses on the understanding, development, and additive manufacture of a 3D printed snake skin-inspired texture pattern. The design functionalities of snake skin were determined through the study of the snake species Python Regius otherwise known as the ball python. Each scale of a snake has hierarchical texture with hexagonal macro-patterns aligned on the ventral surface of the skin with overriding anisotropic micro textured patterns such as denticulations and fibrils. Using a laser-powder bed fusion (L-PBF) process, 420 stainless steel samples were 3D printed which closely resemble the above described directional texture of natural snake skin. This printed surface …

Asymmetric Synthesis Of The C29-C34 Moiety Of Fragment A Of The Antascomicin B & Thermal Azole Based Claisen Rearrangements, Dharma Theja Nannapaneni

Graduate Theses and Dissertations

The dissertation describes asymmetric synthesis towards C29-C34 moiety of fragment A of the Antascomicin B and Thermal azole based Claisen rearrangements. In chapter 1, we describes asymmetric synthesis towards C29-C34 moiety of fragment A of the Antascomicin B. The non-immunosuppressant Rapamycin, Ascomycin, and Tacrolimus (FK506), strongly binds with FKBP12, the ligand FKBP12 complexes responsible for immunosuppressive activity. Antascomicin B structurally related to Rapamycin, Ascomycin, and Tacrolimus (FK506), binds strongly to FKBP12, yet does not shown immunosuppressive activity. The ligand FKBP12 binding complexes shown to have potent neuroprotective and neurogenerative properties in mouse models of Parkinson’s disease. The linear synthesis of …

Coccidiosis Vaccination And Nutrient Utilization In Broiler Chickens, Alyson Elaine Gautier

Graduate Theses and Dissertations

Four experiments were conducted to evaluate the interrelationships among coccidiosis vaccination and nutrient utilization in floor-reared broiler chickens. Experiment 1 longitudinally compared the effects of coccidiosis vaccination and a chemical coccidiostat on broiler performance, nutrient digestibility, and intestinal morphology. Coccidiosis vaccination had no significant impact on morphology, overall body weight gain and feed intake of vaccinated birds, although vaccination impaired overall FCR. Vaccination elicited a transient reduction in digestibility of energy and nutrients, particularly for lipids, but vaccinated birds were able to recover from these reductions by 20 d. Experiment 2 assessed the impact of vaccination in digestibility of different …

Quantitative Analysis Techniques For Assessing Organelle Organization And Dynamics In Individual Cells, Isaac Vargas

Graduate Theses and Dissertations

In biomedical optics and microscopy, the organization and morphology of organelles have been widely studied. In spite of novel imaging techniques, there is still a lack of quantitative tools to easily measure cellular characteristics from image data. Previous studies have explored multiple approaches to assess organelle organization and alignment, resulting in complicated and extensive algorithms that are both subject to multiple steps of image processing and influenced by non-cellular artifacts. In this thesis, a technique called the Modified Blanket Method (MBM) is introduced to quantify organelle organization through measurements of fractal dimension (FD) on a pixel-by-pixel basis. With the use …

Science And Risk Analysis In Cptpp/Sps-Plus: Role Model Or Unbearable Burden?, Kuei-Jung Ni

Journal of Food Law & Policy

Trade in food and agricultural products accounts for a major part of global trade, and the trade continues to alert domestic consumers to the risks associated with modern food processing and production methods. The Trans-Pacific Partnership Agreement (TPP), now rebranded as the Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP), represents a new model of mega-regional trade pacts posed to set higher standards for promoting and streamlining trade liberalization. Because of concerns with national food safety regulations that could constitute forms of non-tariff barriers, the CPTPP, in contrast to the World Trade Organization (WTO), stipulates further rules on parties’ sanitary …

Going Hemp Wild: Understanding The Challenges And Opportunities For Fda Regulation Of Cbd In Food Products, Hannah Catt

Journal of Food Law & Policy

After the passage of the 2018 Farm Bill, champions of hemp began to tout opportunities for farmers and businesses involved with the crop. The industry has rallied around one of hemp’s major byproducts, cannabidiol, or CBD. However, the demand for CBD has left the Food and Drug Administration (“FDA”) playing catch-up. This article explains what CBD is, how it is derived, current FDA-approved uses, and a current path forward for the FDA in creating guidance for industry and consumers.

Species Richness And Ecological Diversity Of Myxomycetes And Myxomycete-Like Organisms In The Tropical Forests Of Brazil, Isadora Lima Coelho

Graduate Theses and Dissertations

Tropical rain forests cover less than two percent of Earth's surface, yet they sustain the greatest diversity of living organisms on the planet. Tropical rain forests cover nearly 73% of the Brazilian territory and besides harboring some of the most biodiverse ecosystems on the planet, this vast area also houses about 83% of the Brazilian population. Approximately 175 million people live in urban and rural areas with fragments of coverage of these biomes which contributes to the loss of biodiversity that rapidly increases over the years. Furthermore, the majority of the taxonomic and ecological efforts to describe and protect the …

Changes In Cortical Processing Following Unilateral Visual Cortex Deafferentation, Matthew Gannon

Graduate Theses and Dissertations

After the loss of inputs, cells in visual cortex adapt and begin representing space beyond their classical receptive fields. This ability for functional reorganization is a phenomenon known as neuroplasticity. Homonymous hemianopia is a unique case of this scenario that results from hemispheric deafferentation, or when all visual inputs in to one hemisphere of the brain are lost. This condition occurs due to unilateral damage of the post-chiasmatic geniculo-striate pathway, the network that carries visual information from one side of visual space to the visual cortex for processing. Damage to this pathway causes perceptual blindness in the side of space …

Social Anxiety Reduction In The Context Of Social Modeling Utilizing A Placebo Alcohol Beverage, Kyle K. Jackson

Graduate Theses and Dissertations

Alcohol misuse and elevated social anxiety are found to be highly comorbid, and being exposed to social models consuming alcohol can increase one’s consumption. Yet no research has thus far examined whether the internal experience of alcohol consumption (e.g., social anxiety reduction) can also be transmitted via social modeling. This bar-lab study examined the impact of social modeling behavioral cues of social anxiety on emerging adult drinkers. It was hypothesized that those exposed to a social model experiencing an apparent social anxiety reduction from drinking would themselves report lessened state social anxiety following a placebo drink, and that this effect …

Functional Importance Of Lipin Phosphorylation, Stephanie Elizabeth Hood

Graduate Theses and Dissertations

Highly conserved throughout evolution, lipins are dual functioning proteins found from yeast to humans. Functioning in the cytoplasm as phosphatidate phosphatase enzymes (PAP), lipins produce diacylglycerol that serves as a precursor for neutral fats and membrane phospholipids. Alternatively, nuclear lipins are responsible for the regulation of metabolic genes. Interestingly, both the mammalian lipin 1 paralog and the single Drosophila Lipin ortholog are highly phosphorylated proteins. Target of rapamycin (TOR) has previously been identified as one of the kinases that controls the subcellular localization of both lipin 1 and Drosophila Lipin. However, other serine and threonine kinases are predicted to be …

Methods To Evaluate Ruminant Animal Production Responses, Jose Manuel Diaz Gomez

Graduate Theses and Dissertations

In experiment 1, 80 steers (197.0 kg initial body weight; BW for fall, 116.9 kg for spring), were stocked at 2.45 and 4.1 calves/ha in fall and spring, respectively in 16 tall fescue pastures [fall ergovaline (EV) = 1,475 ppb and spring EV = 1,173 ppb] under 2 treatments, mineral (MIN) (n = 8) and cumulative management (CM) (n = 8). Forage allowance did not differ (P = 0.76) between CM and MIN during fall but differed during spring (P ≤ 0.05, 2.55 vs. 3.22 kg DM/kg BW, for MIN and CM, respectively). For fall, average daily gain (ADG) resulted …

Natural Variation In Yeast Stress Signaling Reveals Multiple Paths To Similar Phenotypes, Amanda N. Scholes

Graduate Theses and Dissertations

Natural environments are dynamic, and organisms must sense and respond to changing conditions. One common way organisms deal with stressful environments is through gene expression changes, allowing for stress acclimation and resistance. Variation in stress sensing and signaling can potentially play a large role in how individuals with different genetic backgrounds are more or less resilient to stress. However, the mechanisms underlying how gene expression variation affects organismal fitness is often obscure.

To understand connections between gene expression variation and stress defense phenotypes, we have been exploiting natural variation in Saccharomyces cerevisiae stress responses using a unique phenotype called acquired …

Observable Persistent Effects Of Habitat Management Efforts In The Ozark Highlands After 10 Years, Maxwell Carnes-Mason

Graduate Theses and Dissertations

I investigated the lasting impacts of a management plan designed to improve oak regeneration and benefit wildlife in the Ozark Highlands in Madison, Co., AR. To assess the efficacy of the management plan, I used variables relevant to the success and establishment of oak trees. Controlled burns and selective logging were used to thin the canopy, increase ground level productivity, and increase the abundance of small mammals. I used measurements of overstory and understory densities, light availability, and the density of mice in the genus Peromyscus across time to look at the lasting impacts of management. Different treatment plots were …

Recovered Images: Medieval Echoes In C. S. Lewis’S Space Trilogy, Nathan Earl Houston Fayard

Graduate Theses and Dissertations

C. S. Lewis has begun to garner more scholarly attention in the last few decades, but his first novels, his science fiction or Space trilogy, continue to be largely ignored by academia. Yet, these three novels are deserving of more serious study, as they are pioneering works of literary science fiction, and even more surprisingly, of literary medievalism. Though long derided as mere reactionary attacks on Modernism and science, when properly understood, these strange and wonderful tales actually reveal the complexity and nuance of Lewis’s response to his times. In them, the Inkling author creates a unique combination of the …

Establishing An Ideal Inclusion Rate Of Fermented Soybean Meal And Sodium Butyrate On Growth Performance, Complete Blood Cell Count, And Nutrient Utilization In Nursery Pigs, Kristopher A. Bottoms

Graduate Theses and Dissertations

To evaluate increasing levels of sodium butyrate (SB) in nursery diets on growth performance (Experiment 1 & 2), complete blood cell count (Experiment 2), and the optimal level of fermented soybean meal for maximum performance in weanling pigs (Experiment 3), weaned pigs were blocked with initial body weight (BW) and allotted to dietary treatments. Treatments were: 1) Control (C) moderately complex corn-soybean-meal based supplemented with 0.05% benzoic acid (BA), but devoid of SB; C diet supplemented with 0.05%, 0.10%, or 0.15% SB (Experiment 1). Treatments in experiment 2 consisted of 1) a moderately complex corn-soybean-meal based diet devoid of SB …

Toward Understanding The Mechanism Of Protein Targeting In The Chloroplast Signal Recognition Particle Pathway, Mercede Furr

Graduate Theses and Dissertations

Protein targeting is a vital cellular function. The signal recognition particle (SRP) pathway is a universally conserved targeting system present in the cytosol and used to co-translationally target many proteins to the inner membrane of prokaryotes and the endoplasmic reticulum of eukaryotes. The chloroplast has a homologous SRP system which post-translationally targets light harvesting chlorophyll binding proteins (LHCPs) to the thylakoid membrane for integration. The chloroplast SRP (cpSRP) is a heterodimer with a 54 kDa subunit equivalent to SRP54 in the canonical pathway. In addition, cpSRP contains a novel 43 kDa subunit which is a unique and irreplaceable component. cpSRP43 …

Synthesis Of Cellulose Nanocrystal-Gold Nanoparticle Hybrid System For Surface Plasmon-Enhanced Property, Mahshid Iraniparast

Graduate Theses and Dissertations

Gold nanoparticles (AuNPs) have been brought to the forefront of various applications, ranging from theranostics, to organic photovoltaics, to biosensing owing to their localized surface plasmon resonance (LSPR) property. However, this property needs to be improved in order to allow for high sensitivity and quantitative detection of biomolecules. Hybrids of AuNPs with low-dielectric cellulose nanocrystal (CNCs) would yield enhancement of the LSPR property, which is driven by the confinement of electron oscillation at their interfaces. This study proposed a seed-mediated growth method to synthesize hybrids of CNCs-AuNPs. Sulfate groups on the surface of CNCs served as the sites for the …

Detecting Differentially Co-Expressed Gene Modules Via The Edge-Count Test, Anne Gratius Lin

Graduate Theses and Dissertations

Background

Gene expression profiling by microarray has been used to uncover molecular variations in many different diseases. Complementary to conventional differential expression analysis, differential co-expression analysis can identify gene markers from the systematic and granular level. There are three aspects for differential co-expression network analysis, including the network global topological comparison, differential co-expression cluster identification, and differential co-expressed genes and gene pair identification. To date, most of the methods available still rely on Pearson’s correlation coefficient despite its nonlinear insensitivity.

Results

Here we present an approach that is robust to nonlinearity by using the edge-count test for differential co-expression analysis. …

Applications Of Ionic Liquids In Membrane Separation, Mohanad Kamaz

Graduate Theses and Dissertations

Ionic liquids represent an emerging attractive material in membrane technology. The central theme of this doctoral dissertation is to develope novel membranes using ionic liquids. Two different approaches were used to prepare ionic liquid membranes including the immobilization of ionic liquid within the membrane pores or the use of pressure assembly method to deposit a selective ionic liquid layer on the top membrane surface.

In chapter 2, imidazolium ionic liquids with three different alkyl halides were successfully synthesized and used to prepare supported ionic liquid membranes (SILMs). SILMs preraper were tested for aqueous and nonaqueous applications. For nonaqueous applications, the …

Quantitative Study Of The Antimicrobial Effects Of Silver On The Motility Of Escherichia Coli, Benjamin Russell

Graduate Theses and Dissertations

In recent decades, the number of antibiotic-resistant bacterial infections has grown to become a serious global threat. This rise can be attributed to the widespread misuse of antibiotics and the lack of newly developed drugs to fight resistant organisms. Novel bactericidal substances have, therefore, garnered significant research interest. Silver, due to its powerful antimicrobial effects, is one such substance. Silver is typically most effective in cationic form; however, advancements in nanotechnology have paved the way for the controlled fabrication of nano-silver. Silver nanoparticles have been shown to have increased antibacterial potency for a variety of reasons, including the release of …

Serum Myostatin And Igf-1 As Biomarkers Of Sarcopenia: A Proof-Of-Concept Design, Ashley Binns

Graduate Theses and Dissertations

The population comprising older adults is growing exponentially, as are healthcare related costs. Nearly $20 billion is annually expensed by older adults for health-related issues affiliated with age-related decline in skeletal muscle mass. Yet, diagnostic criteria are not readily utilized in clinical practice. PURPOSE: Therefore, the purpose of this study was to provide evidence for use of blood biomarkers (myostatin, IGF-1) to predict appendicular skeletal muscle mass (ASM) among middle-aged and older adults. METHODS: A cross-sectional study was conducted among 106 individuals (n = 68 females; n = 38 males) aged ≥ 40 years of age (60.1 ± 11.1 y) …

The Physicochemical Properties Of Soy Protein Hydrolysate And Its Formulation And Stability With Encapsulated Probiotic, John Stricklin Edwards

Graduate Theses and Dissertations

Soy protein isolate (SPI) and probiotics can serve as a functional ingredient and beneficial supplement, respectively, to food formulations, but few studies focus on the compatibility of these two ingredients. The objective of this study was to prepare soy protein isolate (SPI) from defatted soybean flour and identify an optimal hydrolysis protocol to create soy protein hydrolysates (SPH) with improved solubility and functional properties and achieve an optimum encapsulation technique for probiotics and to determine the in vitro viability of encapsulated probiotic cells with SPH in a gastrointestinal environment. The SPI was prepared using an alkaline extraction procedure for solubility …

Created For Connection: The Impact Of A Faith-Based Christian Marriage Enrichment Program, Chad N. Imhoff

Graduate Theses and Dissertations

The purpose of this study was to explore the effects of Created for Connection (CFC), a faith based marriage enrichment program on relationship satisfaction, adult attachment style and adult attachment behavior. This study further adds to the existing knowledge base related to faith-based programs delivered in an intensive weekend format (Johnson & Sanderfer, 2016). Participants were volunteers from the local community who identified as Christian. To ascertain the effectiveness of CFC, three self-report measures were administered at three different intervals: two weeks before the program, two weeks following the program and a six-week follow-up. I measured attachment anxiety, attachment avoidance, …

Aglycon Modifications Of Ipomoeassin F: Synthetic Route Development And Analog Synthesis To Enable Further Sar Studies, Eric Barber

Graduate Theses and Dissertations

The ipomoeassin family of resin glycosides were discovered to have a high potency against numerous cancer cell line, with ipomoeassin F being the most potent among the family of natural products. Interestingly, one of the few differences between ipomoeassin F and the other compounds is the length of the fatty-acid derived aglycon. As the mechanism of action for this family of resin glycosides is unknown and didn’t have any significant COMPARE correlation with the recorded anticancer agents in the National Cancer Institute (NCI), further SAR studies are needed. Drawing on the differences between ipomoeassin F and the other ipomoeassins, it …

Anti-Inflammatory Effects Of Cruciferous And Apiaceous Vegetables In C57bl/6j Mice Colon, Rosa Moreno Narvaez

Graduate Theses and Dissertations

Previous studies have demonstrated chemo-preventive potential of cruciferous and apiaceous vegetables against colon cancer. Colon inflammation is one condition closely related with colon cancer initiation. Therefore, we wanted to compare if total western diet (TWD) was as pro-inflammatory as died-induced obesity (DIO) and a better dietary model for human conditions, and determine if diet supplementation with cruciferous (broccoli, watercress and cabbage) or apiaceous vegetables (celery and parsnip) could reduce dietary inflammation, and which vegetable was more effective.

Male CBL57/6J mice were fed chow for seven days, on day eight, mice were assigned to one of the following diets: American Institute …

Qtl Mapping Of Panicle Architecture And Yield-Related Traits Between Two U.S. Rice Cultivars 'Lagrue' And 'Lemont', Adam D. Rice

Graduate Theses and Dissertations

Grain yield in rice consists of multiple yield components such as number of panicles/plant, number of tillers/plant, and number of seeds/panicle. Panicle architecture is an important yield trait yield as the number of seeds on a panicle greatly contributes to the overall panicle yield. A QTL analysis and mapping study on panicle architecture and yield-related traits was performed to identify major QTL and candidate genes associated with the traits. The first objective of the project was to do a yield study evaluating 15 agronomic traits between each of the four U.S. rice cultivars, ‘LaGrue’, ‘Lemont’, ‘Bengal’, and ‘Mars’, to determine …

Global Acetylation Dynamics In The Heat Shock Response Of Saccharomyces Cerevisiae, Rebecca E. Hardman

Graduate Theses and Dissertations

All organisms face a constant barrage of environmental stresses. Single-cell organisms such as Saccharomyces cerevisiae, or common Baker’s yeast, must rely solely on cellular responses in order to survive. This response must occur in a rapid and highly coordinated manner to quickly inhibit all unnecessary processes and shuttle all available resources to those necessary for survival. One method that cells utilize for rapid protein regulation is the use of post-translational modifications. Enzymes within the cell add or remove a variety of chemical modifications, thus altering the local chemical environment of a protein. This creates a conformational change in the protein …