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A Molecular And Bioinformatic Investigation Into The Phylogenetic Relationships And Life Cycles Of Amoeboid Protists, Alexander K. Tice

Theses and Dissertations

Eukaryotic organisms that cannot be classified as animals, land plants, or fungi are termed protists. Despite the fact that protists represent the majority of eukaryotic diversity, these organisms have received relatively little attention from biological researchers beyond morphological characterization. Reasons that likely contributed to their neglect include their mostly microscopic nature, that only a few lineages are the causative agents of human disease, that laboratory cultivation can be challenging, and that species concepts for the majority of protists was vague in many lineages. Initial attempts to resolve relationships among eukaryotes produced the five kingdoms model. This model suggested protists were …

Exploring Korean Hand Therapy In Treating Plantar Fasciitis: A Pilot Study, Alice A-Hui Osborn Fetzer

Theses and Dissertations

PF is one of the most common foot and ankle problems. People with PF experience mild to severe pain that interferes moderately with activities of daily living (ADL). Due to chronic pain that interferes with ADL, people with PF often use non-steroidal anti-inflammatory medications and/or acetaminophen. These medications alleviate pain but cannot eliminate it. Additionally, with chronic use, these medications can cause well-known adverse side effects. The purposes of this study were to investigate the effect of Korean Hand Therapy (KHT) in (1) treating the pain experienced in patients with plantar fasciitis (PF), (2) evaluating its impact on functionality, and …

Dairy Milk And Plant-Based Alternative Beverage Purchasing Factors: Consumer Insights, Jeffrey Alan Rime

Theses and Dissertations

From 2000 to 2019, total volume of fluid milk consumption in the USA has steadily fallen. Many factors have played a role in this trend, including competition with plant-based alternative beverages (PBABs). Comparably, sales of PBABs such as almond “milk” have increased over the same duration. Consumer research has identified key beverage characteristics as purchase drivers for both beverage types. This study sought to evaluate the relative importance of these characteristics, investigate the effect of label statements on ratings of their acceptability, and analyze the settings in which and occasions during which consumption of dairy milk and PBABs occurs. This …

Governing Dynamics Of Divalent Copper Binding By Influenza A Matrix Protein 2 His37 Imidazole, Kelly Lewis Mcguire

Theses and Dissertations

Influenza A is involved in hundreds of thousands of deaths globally every year resulting from viral infection-related complications. Previous efforts to subdue the virus by preventing proper function of wild-type (WT) neuraminidase (N), and M2 proteins using oseltamivir and amantadine (AMT) or rimantadine (RMT), respectively, exhibited success initially. Over time, these drugs began exhibiting mixed success as the virus developed drug resistance. M2 is a proton channel responsible for the acidification of the viral interior which facilitates release of the viral RNA into the host. M2 has a His37-tetrad that is the selective filter for protons. This protein has been …

Breaking The Organic Mold: Introducing Copper Into The Influenza A Arena With Neutral And Divalent Complexes, Jonathan D. Lynch

Theses and Dissertations

Influenza A (IVA) continues to pose a growing global threat even as current medications are becoming less effective. One of the main avenues of research into new anti-IVA drugs is its homotetrameric Matrix 2 proton channel (M2A), without which the virus would be unable to release its viral RNA into the host cell. The drug amantadine used to bind and block M2A until near-ubiquitous resistance formed as an M2A-S31N mutation, starting around 1995 and proceeding to 2005 when amantadine was disallowed for use as an anti-IVA drug. The standard organic structure currently being used for M2A inhibitor research comprises an …

Does Immigration Help To Explain Child Stress?, Elizabeth Marie Koch Sigler

Theses and Dissertations

The impacts of childhood stressors are harmful to the emotional and physical well-being of children of all ages. Past research has suggested that children experience increased stress due to change. One subgroup of the United States population that experiences change, is immigrants. Research provides empirical evidence of adolescent immigrant stress but has failed to examine stress experienced by immigrant children at a young age. The present study investigates how immigration status and child immigration generation might impact child stress at a young age using OLS regression. I predict that immigrant children will experience more stress than non-immigrant children and that …

Valproic Acid Leads To An Increase In Ros Generation By Inhibiting The Deacetylation Of Mitochondrial Sod, Stephen Marc Lucas

Theses and Dissertations

Valproic Acid Promotes Acetylation of Superoxide Dismutase-2 During Neurogenesis. Valproic acid (VPA) is a known developmental toxicant associated with a high prevalence of neural tube defects (NTD). The mechanism of VPA-induced NTD is unclear, but oxidative stress may be implicated. To understand how embryotoxic oxidative stress may occur, we measured superoxide dismutase (SOD) activity following VPA treatment in the embryonic pluripotent P19 mouse carcinoma cell line. In undifferentiated P19 cultures treated with VPA (5 mM), dichlorofluorescein fluorescence increased 15% compared to untreated controls over 20 min, indicating a modest, yet statistically significant increase in ROS generation. Undifferentiated P19 cells were …

A Content Analysis Of Sexuality-Related Scholarship For Sexual Minorities, Chelise Fox

Theses and Dissertations

Sexual minority individuals face disparities of treatment from clinical and medical health professionals. In particular, there is a dearth of research and training surrounding human sexuality topics for sexual minorities. Research on sexual minority groups in this area can contribute to reducing treatment disparities. Consequently, the proposed study is a content analysis of social science literature in order to gauge trends in the amount of research focused on the intersection of sexual minorities and sex research. Articles from a database search of relevant keywords were coded for several variables, including overall level of focus on sexual minorities and on human …

Discovery Of A Novel Regulatory Mechanism Of Tnk1 By 14-3-3 And Its Ubiquitin Association Domain Provides A Potential Therapeutic Targeting Opportunity In Cancer, Tsz Yin Chan

Theses and Dissertations

While a relatively limited number of known oncogenes underlie a large percentage of cancers, a variety of new genes have emerged as low-frequency cancer drivers. Each of these new oncogenes represents a frontier for targeted therapy. However, the discovery of low-frequency targetable oncogenic drivers is challenging. This study focuses on the poorly understood Tyrosine kinase non-receptor-1 (TNK1), which has been reported to have both oncogenic and tumor suppressive functions. TNK1 has been identified to promote cancer cells survival and promote chemoresistance in multiple independent studies. On the other hand, whole-body constitutive deletion of TNK1 in mice caused an increase in …

Understanding Relapse In Self-Perceived Problematic Pornography Users, Erin L. Rackham

Theses and Dissertations

This study explored reasons for relapse among a sample of 938 self-identified problematic pornography users. A combination of numeric content analysis and qualitative coding of responses to an open-ended question about pornography relapse revealed six main categories of reasons for relapse. The mental, emotional, and relational categories were then analyzed in detail, and this analysis revealed significant overlap of responses from the emotional and relational categories. Hence, a new category of relational-emotional reasons for relapse was created and analyzed. The findings from this study highlight the complex interactions of different types of factors driving relapse in self-perceived problematic pornography users …

Analyzing Metacommunity Models With Statistical Variance Partitioning: A Review And Meta-Analysis, Kevin Vieira Lamb

Theses and Dissertations

The relative importance of deterministic processes versus chance is one of the most important questions in science. We analyze the success of variance partitioning methods used to explain variation in β-diversity and partition it into environmental, spatial, and spatially structured environmental components. We test the hypotheses that 1) the number of environmental descriptors in a study would be positively correlated with the percentage of β-diversity explained by the environment, and that the environment would explain more variation in β-diversity than spatial or shared factors in VP analyses, 2) increasing the complexity of environmental descriptors would help account for more of …

Relationship Of Posterior Intracranial Venous Structures In Homo Sapiens And Handedness, Brianne Finley

Theses and Dissertations

The transverse sinus spans the endocranial surface of the occipital bone and ultimately transmits deoxygenated blood to the sigmoid sinus and jugular vein en route to the heart. This paired sinus tends to be more defined on either the left or right side in human crania. Left and right dominance, or the use of one side of the body more than the other, leaves traces on the human skeleton. Methods to determine handedness upon examination of various elements of the human skeleton mostly focus on the use of the extremities, while little research exists examining the skull for evidence of …

Resiliency As A Moderating Factor For The Impact Of Adverse Childhood Experiences On Substance Use In American Indian And Caucasian College Students, Emily Sargent

Theses and Dissertations

College students engage in frequent substance use behaviors and experience related consequences. Previous research suggests American Indians (AIs) experience higher rates of substance use and related consequences. Further, AIs may experience negative substance use outcomes given higher rates of adverse childhood experiences (ACEs). However, resiliency (i.e., experiencing positive outcomes despite adversity in one’s life) may be one factor that moderates the relationship between ACEs and substance use to in order to reduce use and negative consequences. The current study examined alcohol and drug use/consequences, ACEs, and resiliency among AI (n = 69) and Caucasian (CA; n= 91) university students via …

A Histopathological Review Of Immune Response In Largemouth Bass To Parasitic Infections Of Soft Tissues, James D. Stephenson

Theses and Dissertations

The immune response can serve as a key indicator of a fish’s overall health and the effect stressors have on the health of the fish. Anthropogenic factors can stress a fish’s immune system and inhibit immune responses. This study investigated the response of eosinophilic cells and macrophage aggregates to parasites in the livers, spleens, and gonads of Largemouth Bass, Micropterus salmoides. Largemouth Bass were sampled from three bodies of water in the Chattahoochee Valley of varying levels of urbanization. Histopathology of the aforementioned organs was conducted to observe both the parasite density and immune response. Eosinophilic cells were shown …

Three Essays On Ceo Activism, Strategic Choices And Firm Performance, Keshab Acharya

Theses and Dissertations

There is a longstanding societal expectation that business leaders refrain from involving in social and political issues and primarily focus on managing their firms. In recent years, however, there is a growing trend of CEOs taking a stance on controversial sociopolitical issues that are not directly related to their company’s core business. This dissertation consists of three essays focusing on this phenomenon of CEO activism.

In my first essay, given that CEO activism represents a nascent phenomenon, I explore the conceptualization of CEO activism. Additionally, I propose three main motives behind CEO activism: intrinsic, instrumental, and stakeholder-focused. In my second …

Development Of Plant Extract-Based Composite Fibers And Aerogels, Raul C. Barbosa

Theses and Dissertations

The aim of this study is to use the solid templating process of pullulan nanofibers in order to produce biocompatible, biodegradable, and antibacterial aerogels. The developed aerogels were produced using cross-linked pullulan nanofibers, which provide a water-stable structure allowing them to be used as wound dressing material. The morphology, thermal properties, water solubility, and thermal and physical properties of the nanofibers and aerogels were characterized. Furthermore, the antibacterial effect against gram-negative bacteria, Escherichia coli, and the biocompatibility using mouse embryonic fibroblasts (NIH 3T3) were investigated.

Examining The Efficacy Of Cover Crops As An Integrated Pest Management Tool In Organic Farms In The Lower Rio Grande Valley, Lili M. Martinez

Theses and Dissertations

The Lower Rio Grande Valley (LRGV) consists of a mix in subtropical and costal habitats, a combination that provides a favorable environment for the animals and plants that inhabit it. This is a problem for organic farmers as they refrain from using synthetic chemicals and therefore led them to seek other methods of dealing with insect herbivory. Of the many alternative methods available, we looked specifically at integrated pest management methods (IPM) to determine their efficacy in reducing insect herbivory among cash crops. Chapter II discusses an experiment performed in an organic farm in Edinburg, Texas consisting of a two-year …

An Experimental And Computational Mechanical Analysis Of Bone Anchors And Substrate Interface, Samantha May Schultz

Theses and Dissertations

Screw loosening is a common concern in orthopedic surgery. Therefore, this study is a computational and experimental evaluation of bone substrate and cortical screw interface. An axial load test was performed in an Instron with titanium alloy screws with 2.7 mm, 3.5 mm, and 4.5mm diameter orthopedic cortical screws inserted into SawBone with densities varying from 10 to 50 pounds per cubic foot (PCF), incrementing in sets of 10 PCF. SawBone was chosen in place of human bone because it has been shown to emulate the same mechanical properties (1). Twelve samples were prepared for each screw size and substrate …

Graphene Surface Plasmon Applications In Designing Novel Nano-Heterostructure Arrays, Seyededriss Mirniaharikandi

Theses and Dissertations

Graphene is the flat monolayer of carbon atoms constructing a two-dimensional honeycomb lattice with an exotic mechanic, electronic, magnetic, and optical properties. Interestingly, the graphene has been experimentally shown its unique properties in photonics, where the first commercial application of graphene has been realized. Graphene possesses intrinsic plasmons that are electronically tunable, adjustable, and have low dissipation. Recently, the combination of graphene with noble metals and semiconductors structures promises a variety of exciting applications for conventional plasmonics and photonics. In this thesis, we present how to efficiently design heterostructure by combining graphene plasmonic metasurface with noble metals and semiconductors. First, …

Optimal Control Of Multiphase Free Boundary Problems For Nonlinear Parabolic Equations, Evan Cosgrove

Theses and Dissertations

Dissertation research is on the optimal control of systems with distributed parameters described by singular nonlinear partial differential equations (PDE) modeling multi-phase Stefan type second order parabolic free boundary problems. This type of free boundary problems arise in various applications, such as biomedical engineering problem on the laser ablation of biological tissues, aerospace engineering problem on the ice accretion in aircrafts mid-flight, biomedical problem on the growth of cancerous tumor, and many other phase transition processes in thermophysics and fluid mechanics. The aim of the optimal control of distributed free boundary systems is two fold: identification of functional parameters of …

A Feature-Based Approach To Function Modeling And Reasoning For Thermal-Fluid Systems Engineering, Lakshmi Narasimhon Athinarayana Venkatanarasimhan

Theses and Dissertations

This research is focused on extending the language of function modeling by developing CAD-like features that are built using primitive functions. These features are reusable units of functions that represent the working principle of a system of higher level of abstraction than the ones of the primitive functions published in prior literature. This approach can be used to also establish an alternate concept/working principle that satisfies the same features, and thus enabling the integration of function models into previously established concept generation programs. It is expected that designers perceive concepts at different levels of abstractions. As a result, the feature-based …

Analysis Of The Role Of Dnaa Recognition Site Position In Directing Assembly Of The Pre-Replicative Complex In Escherichia Coli, Christopher Aaron Czerwonka

Theses and Dissertations

Prior to initiating new rounds of DNA replication, all cells assemble pre-replicative complexes (pre-RC) consisting of initiator proteins and regions of DNA termed origins of replication. In the bacterial model system, E. coli, multiple copies of the initiator protein, DnaA,assemble into a complex with the unique chromosomal replication origin, oriC, to produce a pre-RC that unwinds the DNA helix, preparing the origin for the new replication forks. Nine base pair (bp) low affinity DnaA recognition sites are distinctly arrayed in each half of oriC and both arrays are bounded by high affinity recognition sites. Although it is known that DnaA …

Alternative Material Selection For Oyster Restoration With An Emphasis On Living Docks, Bridgette Soucy

Theses and Dissertations

Oyster restoration efforts, including Living Shoreline and Living Dock projects, utilize aquaculture-grade plastic oyster mats to mitigate the decline of benthic communities. Aquaculture-grade plastic are known for strength, durability, and resilience to degradation in seawater. Over time, plastics break into microscopic segments commonly referred to as microplastics. Microplastics represent a major concern as marine organisms mistake the small particles for food. Plastics bioaccumulate in marine species, which impacts the marine food web and humans. In order to reduce further negative anthropogenic impacts, natural fibers and nature-inspired concrete mixtures were utilized across a series of experiments in order to determine an …

Analysis And Computation Of Polaritonic Systems In Infrared Regime For Sensing Applications, Abdelgader Ahmed Alshiekh Alsalhin

Theses and Dissertations

Generally, the aims of this work tend to focus on introducing novel designs for IR-sensing and a solid related knowledge based on computational analysis and investigations for polaritonic systems. This modern field of nanophotonics has been interested and promising nowadays thanks to the development in nano-fabrications and computing power and speed. Therefore, the theme-work is organized into two main parts along with the goals were addressed initially. The first part provides the necessary concepts for different responses of materials exposed to electromagnetic (EM) intensity which usually known as EM-matter interaction. Also, this part highlights how engineering these interactions in nano-scale …

Unbinding Of Testosterone From The Androgen Receptor And Two Bf-3 Site Mutants, Muniruzzaman Chowdhury

Theses and Dissertations

The androgen receptor (AR) can be activated by molecules binding in the steroid binding pocket. It can also be regulated allosterically by cofactors binding to the AF-2 surface site as well as by exogenous small molecules binding to the BF-3 surface site. Recent data indicated that mutations in the BF-3 site changed the amount of the endogenous steroid needed to activate the receptor, indicating that mutations of BF-3 can cause an allosteric effect. Molecular dynamics and steered molecular dynamics simulations were used to study the allosteric effect of the mutations on AR structure and the unbinding pathways of testosterone (TES) …

Nonwovens Of Ceramic Decorated Cellulose Based Fine Fibers For Leaded Water Purification, Alejandro J. Castillo

Theses and Dissertations

Fine fibers of cellulose acetate were Forcespun and used to make nonwoven mats of cellulose. Nonwovens were activated using a solution combustion synthesis which deposited iron nitride onto fibers. Cellulose and cellulose composite mats were tested as adsorbents for lead ion in water. Cellulose showed slightly higher adsorption capacities (mg/g) up to 1300 mg/g lead loading. Adsorption data were further analyzed using several isotherms, of which the Dubinin-Raduskevich gave the best fits.

Identifying Positive Selection In Multiple Subspecies Of Xylella Fastidiosa, Daniel Doroteo Flores

Theses and Dissertations

For this study, we will be looking to identify positive selection in eight genomes of the bacterial plant pathogen Xylella fastidiosa. A previous study used a branching method that identified 2 genes with positive selection along with a site-specific method identifying 34 genes showing positive selection. This current study focused specifically on the site-specific method, resulting in 28 genes (of 1,039 tested) showing positive selection. Of the 28 genes showing positive selection, 12 of them come from the pathogenicity, virulence and cellular structural categories. The remaining genes are found in the biosynthesis, metabolism, macro metabolism, and cellular process categories. …

Genetic Analysis Of Pi3k And Mtor Inhibition In U87mg Glioblastoma Cell Line, Carl G. Litif

Theses and Dissertations

NVP-BEZ235 is a Glioblastoma Multiform chemotherapeutic dual PI3K/mTOR pathway inhibitor created in 2008 and has since been proven experimentally to induce pluripotentcy in oncological cell populations. The inhibition of PI3K and mTOR has shown to coerce phenotypes associated with stem cell markers, most notably OCT4. It is necessary to understand the genetic composure of how PI3K/mTOR inhibited tumor cells are bypassing the canonical pathway for proliferation and growth and utilizing other parallel sources for tumor invasion into other neural regions. Taking a genetic approach with RNA-sequencing allowed us to gain insight into how glioblastoma interact with cytoskeleton factors MAPK4 and …

Optimizing Species Selection For Forest Restoration In The Lower Rio Grande Valley, Faeqa Mohsin

Theses and Dissertations

Over the past four decades, the Lower Rio Grande Valley has been reforested with over 3.3 million native thornscrub plants in old agricultural land through transplanting native species. However, assessments of LRGV forest restoration efforts are scarce, and to address the knowledge gap, this study examined species-specific responses to restoration interventions (RIs) aimed at minimizing seedling mortality for optimizing species selection. A critical period for forest restoration in old croplands is the seedling stage, where high mortality occurs due to the interactive effects of abiotic stress, compromised soil nutrient status from intensive agriculture, and mammalian herbivory. So, we evaluated seedling …

The Long-Term Persistence And Tissue Tropism Of Brazilian Zika Virus In Monodelphis Domestica, Marisol Morales

Theses and Dissertations

Zika virus (ZIKV) rose as a major public health concern due to the congenital abnormalities of infants born to infected mothers during the 2015 Latin American outbreak. While animal models such as transgenic mice and nonhuman primates are used to study ZIKV pathogenesis, they display various limitations. Additionally, the persistence and tissue distribution of long-term ZIKV infection remains unknown. We describe the laboratory opossum, Monodelphis domestica, as a potential new model for ZIKV pathogenesis research to address these issues. We utilized immunohistochemistry, RT-PCR, and ELISA to show that: infant animals inoculated intracerebrally were susceptible to infection, ZIKV infection persisted …