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Effects Of M6a Dna Methylation By Bacterial Methyltransferase In Colorectal Cancer, Fabian Alejandro Mendoza Galvan

Dissertations and Theses (Open Access)

Effects of m6A DNA methylation by bacterial methyltransferase in colorectal cancer Fabian Alejandro Mendoza Galvan Advisory Professor: Angela H. Ting, Ph.D. Fusobacterium nucleatum animalis (Fna) is found in the human oral cavity and gut. A distinct clade of Fna is primarily enriched in the tumor microenvironment (TME) and within colorectal cancer (CRC) cells. This clade DNA methylation pattern is primarily catalyzed by a cell-cycle regulated methyltransferase (CcrM) ortholog, M.FnI, that targets the GANTC sequence motif through methyl-6-Adenine (m6A) DNA methylation. We hypothesized that M.FnI enzyme can induce m6A methylation abnormalities in CRC cells to promote cancer progression. Evidence for endogenous …

A Tractable Nematode Model For The Emerging Fungal Pathogen, Candida Auris, Melissa Martinez

Dissertations and Theses (Open Access)

Candida auris is an emerging multidrug-resistant opportunistic fungal pathogen. It

poses a significant threat to immunocompromised patients and those with prolonged stays in

healthcare facilities. C. auris spreads rapidly in health care facilities through enhanced

colonization of skin and abiotic surfaces. The genetic factors contributing to this ability and to

the virulence, drug resistance, and stress-tolerant nature of C. auris are largely unknown.

Current animal models of C. auris infections are not well standardized and report conflicting

results. Additional animal models of virulence are needed, especially those amenable to high-

throughput analysis. The nematode Caenorhabditis elegans has been validated as …

Targeting Breast Cancer Brain Metastasis Through Novel Combination Of Fda-Approved Orally Active Blood-Brain Barrier Permeable Ret And Tgli1 Inhibitors, Joshua Cha

Dissertations and Theses (Open Access)

Breast cancer is the most diagnosed cancer in American women, and breast cancer brain metastasis (BCBM) exhibits the worst prognoses with a life-expectancy averaging at 6 months. This short life expectancy is largely attributed to the lack of effective treatment. Many challenges remain unsolved, including the limited number of actionable targets for targeted therapy and effective blood-brain barrier (BBB) permeable drugs that are safe without promoting drug resistance. Therefore, there is an urgent call for identification of novel therapeutic targets and development of BBB-permeable drugs. One of the potential targets identified by our lab for BCBM targeted therapy is the …

Pattern Dynamics And Stochasticity Of Brain Rhythms And Spike Trains In A Tauopathy Mouse Model Of Alzheimer’S Disease, Clarissa M. Hoffman

Dissertations and Theses (Open Access)

Systems neuroscience posits that every aspect of perceived physical reality, every aspect of animal and human behavior, and every cognitive phenomenon emerges from patterns of neuronal activity. While most researchers embrace this idea, there are major difficulties in describing and analyzing these complex neuronal dynamics—spike flows produced by cells ensembles, synchronized extracellular field oscillations, and other patterns—which limits our understanding of how the activity of individual neurons and the whole-animal cognition and behavior might be connected. In particular, we lack the approaches and even the semantics for connecting the individual cell outputs and the integrated results of their activity. Current …

Characterization Of Staphylococcus Aureus Clinical Isolates From Deep Musculoskeletal Infections For An In Vitro Biofilm Model For Phage Therapy, Raquel C. Luna

Dissertations and Theses (Open Access)

The rise of multidrug-resistant (MDR) infections is a growing concern in the treatment of deep musculoskeletal infections (MSKIs) and orthopaedic device-related infections (ODRIs). Staphylococcus aureus is responsible for about one third of these infections due to its strong biofilm forming capacity, presence on human skin, and the large number of antibiotic-resistant variants. Bacteriophage (phage) therapy is now being considered as a treatment for MDR MSKIs/ODRIs. We are investigating the use of phage encapsulated into or adsorbed onto biodegradable microspheres for local delivery to the site of these MDR infections. We determined that the anti-staphylococcal phage K effectively lyses the S. …

From Antigen Presentation To Tumor Control: Mechanisms Of Type I Conventional Dendritic Cell-Based Cancer Vaccines, Josue E. Pineda

Dissertations and Theses (Open Access)

Type 1 conventional dendritic cells (cDC1s) are important for generating and sustaining antitumor immunity. Accordingly, the abundance of cDC1s in human tumors correlates with improved outcomes in cancer. Capitalizing on this role, we previously demonstrated that vaccination with in vitro-derived murine cDC1s elicits durable tumor control in multiple preclinical models; however, the immunological mechanisms underlying the efficacy of cDC1 vaccination remain unclear. Here, we examined whether in vitro-derived cDC1s resemble tumor-infiltrating DC populations and whether MHC-I and MHC-II antigen presentation contribute to cDC1-mediated tumor control following vaccination in melanoma.

As expected, MHC-I- or MHC-II-deficiency had minimal impact on …

Membrane Organization Of Rheb And Rhoa: Roles In Function And Allosteric Druggability, Chase M. Hutchins

Dissertations and Theses (Open Access)

Small GTPases of the Ras superfamily are membrane-bound molecular switches that regulate nearly all major cellular processes, and their dysregulation drives cancers, neurological disorders, and metabolic diseases. While anchored to cellular membranes, the catalytic domains of small GTPases undergo orientation dynamics, adopting distinct configurations that can occlude or expose effector-binding surfaces and modulate signaling output. These dynamics have been characterized in the Ras oncoproteins, but whether they extend across the superfamily and influence allosteric druggability has remained unknown.

In this dissertation, I address these questions through Rheb and RhoA, two small GTPases with complementary differences in subfamily lineage, membrane localization, …

Understanding Epigenomic Landscapes In Cancer Progression And Immunotherapy Response, Jonathan Schulz

Dissertations and Theses (Open Access)

Nonmutational epigenomic reprogramming has emerged as a key hallmark of cancer that plays crucial roles in tumor evolution during its progression and response to therapy. However, the extent and nature of epigenomic reprogramming remains poorly understood. This dissertation examines how epigenetic regulation shapes cancer progression and response to immunotherapy. Working at the intersection of cancer biology and computational genomics, it develops analytical frameworks for characterizing chromatin structure and DNA methylation across diverse tumor contexts and uses these frameworks to address two complementary biological questions: how promoter-associated chromatin organization varies across cancer types, and how epigenetic perturbation modulates tumor immunogenicity in …

Understanding Vaccine Hesitancy In Veterinary Medicine: A Review Of Client Attitudes, Grace Moore

Undergraduate Honors Capstone Projects

Uncertainty toward vaccination, long recognized as a public health concern in human medicine, is increasingly recognized within veterinary contexts, posing risks to both animal and community health. This literature review examines the development, causes, and implications of reduced vaccine confidence in veterinary medicine, with emphasis on small animal and some large animal practices. The review combines historical and current research to explore how vaccination perceptions have evolved among veterinarians and clients, and how factors such as the COVID-19 pandemic have shaped current attitudes.

The literature highlights recurring themes surrounding vaccine reluctance in veterinary settings. Client perceptions of safety, efficacy, and …

Desert Deep: The Great Salt Lake's Evanesce And The Gravity Of Recovery, Avery Truman

Undergraduate Honors Capstone Projects

The Great Salt Lake has been shrinking since the mid-19th century for several reasons, primarily due to a higher evaporation rate caused by climate change and water diversion from the Bear, Weber, and Jordan rivers. This problem will cause mass ecosystem destruction, release toxic chemicals into the air, and strand migrating birds. As an environmental studies and geography major, I’ve spent a lot of time learning about the Great Salt Lake in my courses. I decided to write Desert Deep, a series of essays, after I took my first creative nonfiction writing class. The goal was to tell the …

Refining Treatment Thresholds Of Insect Pests In South Carolina Soybeans Using Simulated Injury And Natural Populations, Adam Whitfield

All Dissertations

Insect pests are a major limiting factor to profitable soybean, Glycine max (L.) Merr., production in South Carolina, yet current economic thresholds are largely based on historical data and may not reflect modern cultivars, production practices, or input costs. Key insect pests in South Carolina can be categorized into three major feeding groups: defoliators, stem feeders, and pod feeders. Defoliating insects include, but are not limited to, soybean looper, Chrysodeixis includens (Walker); velvetbean caterpillar, Anticarsia gemmatalis (Hubner); green cloverworm, Hypena scabra (Fabricius); grasshoppers; and numerous species of beetles. Stem feeders include, but are not limited to, kudzu bug, Megacopta cribraria …

Abnormal Trafficking And Processing Of Multiple Matrix Metalloproteinases Drive Cartilage Defects In Congenital Disorders Of Glycosylation, Chia-Lun Wu

All Dissertations

Congenital Disorders of Glycosylation (CDG) are rare metabolic diseases caused by defects in glycosylation. Despite identification of over 200 CDG types, the mechanisms linking glycosylation defects to diverse clinical phenotypes remain unclear. This dissertation uses zebrafish models of PMM2-CDG and STT3-CDG to redefine CDG pathogenesis, shifting from a simple glycan deficiency model to one involving disrupted cellular spatial organization.

We identify a protease-dependent pathway underlying craniofacial cartilage defects. Specifically, defective proteolytic processing of N-cadherin, a key adhesion molecule in chondrogenesis, is a central driver of pathology. We further uncover an unconventional trafficking mechanism in which ER stress and altered secretory …

The Impact Of Label Material On Perceived Value And Environmental-Friendliness Of Beverages In Returnable Glass Bottles Versus Actual Environmental Impact Via Life Cycle Assessment, Toni Sharp

All Dissertations

With guidance from the EPA to reduce virgin packaging use and alternatively increase reuse, the concept of reusable packaging has re-emerged as a potential sustainable alternative to single-use and recyclable packaging. For businesses, an understanding of the potential environmental benefits of switching from single-use packaging to reusable packaging, along with consumer willingness to pay for sustainable packaging are paramount. Existing literature on willingness to pay (WTP) for ethical or sustainable products typically relies on consumers’ stated preferences found through surveys using hypothetical products and prices. It has been revealed that sustainability claims printed on the label or products in glass …

Diffuse Radiation Controls On Southern Pine Forest Ecosystem Functioning, Jeremy Forsythe

All Dissertations

Diffuse solar radiation, sunlight scattered by atmospheric aerosols and/or clouds, enhances plant photosynthesis through the diffuse fertilization effect (DFE), increasing ecosystem gross primary productivity (GPP) per unit of incoming radiation. Despite this known effect, pine forests of the southeastern United States remain comparatively understudied in the diffuse light literature. This is a critical knowledge gap, as the southeastern United States sequesters more carbon than any other region of the conterminous country (approximately 176 ± 26 Tg C yr⁻¹, or roughly 56% of national forest net carbon exchange), and the region experiences some of the highest biogenic aerosol loads in North …

Neurobiological Mechanisms Of Attention In Adolescents, Virginia Clark

All Dissertations

Adolescence is a transformative developmental period characterized by profound biological, neurological, and behavioral changes. This dissertation investigates the neurobiological underpinnings of attention in adolescents, emphasizing how internal mechanisms influence and individually shape cognitive development through the endosystem. Rooted in the intersection of human development, learning sciences, and cognitive neuroscience, this work argues for a more integrated understanding of attention as a fundamental cognitive function for learning, one that is behaviorally seen but also biologically and neurologically driven. While developmental science has often emphasized external influences such as family, culture, and environment, this work centers on the adolescent’s internal biological systems …

Men’S Preconception Diet Quality Patterns Predict Supportive Food Parenting Practices: Evidence From A Longitudinal Cohort Study, Mariane H. De Oliveira, Brian K. Lo, Matthew M. Lee, Stephanie Armbruster, Natalie Grafft, In Young Park, Alejandra Cantu-Aldana, Katherine W. Bauer, Rebekah Levine Coley, Sebastien Haneuse, Kirsten Davison, Jess Haines

Human Genetics Publications

Background: Food parenting practices play a vital role in shaping children's food intake, yet evidence linking fathers' earlier diet patterns to later parenting is limited. This study examined the association between fathers' diet quality patterns during their adolescence and food parenting practices during fatherhood.

Methods: Data were drawn from Fathers & Families (F&F), a father-based cohort that recruited participants from an ongoing cohort in the United States that has followed participants since adolescence. Participants (n = 584) reported their dietary intake during adolescence (ages 10-18) using a Youth/Adolescent Food Frequency Questionnaire across multiple survey waves (1996-2011), and reported their food …

Developing An Independent Shallow-Water Survey For The Western Rock Lobster Fishery: Tracking Pre-Recruitment Abundance And Habitat Change, Lucy Rudd, Simon De Lestang, Owen Young, Benjamin Hebiton

Fisheries Research Reports

Background

Puerulus settlement has proven to be a good forecaster of legal recruitment of Western Rock Lobster entering into the commercial and recreational fisheries. However, in 2011, this relationship broke down, with average puerulus settlement levels not being reflected in commercial catch rates four years later. Some northern areas showed unexpectedly low catch rates, while other southern areas showed unexpectedly high catch rates. Since this change followed the 2011 marine heatwave, it was assumed that this event changed some component(s) which were important to the growth and survival of juvenile lobsters. It was determined that a better understanding of this …

Effects Of Applying Humic Acid In-Furrow At Potato Planting, Jonathan Tyler Price

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Many products are marketed towards potato farmers that purport to have a positive return on investment for yield and quality. Humic acids, which are comprised of long chained, organic molecules that can be naturally or industrially made, are currently being marketed in this way. The use of these materials is reported to improve nutrient uptake, increase soil health, encourage vigorous growth, and most importantly, increase yields.  From 2023-2025, the in-furrow application of humic acid containing commercial products was evaluated in Pennsylvania on the cultivars ‘Lehigh’ and ‘Waneta’. Black Label Zn, Duo Maxx, Fertiactyl RhiZn, Humi-flex FA, Hydra-Hume, and Monty's Liquid …

Feeding Ecology In Coastal Systems, Randi L. Cannon

Graduate Theses and Dissertations (2019 - present)

Oysters (Crassostrea virginica) are critical foundation species in estuaries, providing numerous ecological and economic benefits. However, oyster populations have diminished worldwide. Effective oyster restoration and aquaculture require a mechanistic understanding of the physiological and environmental factors that govern oyster feeding, growth, and resilience under changing coastal conditions. We investigated how oyster ploidy and environmental conditions influenced oyster feeding and investigated how changes in abiotic conditions affected behavioral performance of oyster drills (Stramonita spp.), a key oyster predator. To better understand feeding responses and behaviors of both predator and prey we 1) used in-situ filter feeding assays to determine if feeding …

Passive Microwave Remote Sensing Of Flash Drought Impacts On Vegetation, Quinton R. Deppert

School of Natural Resources: Dissertations, Theses, and Student Research

In 2002, Dr. Mark Svoboda characterized a new form of drought known as flash drought. Flash drought was defined as a rapid decline in vegetation health caused by severe heat and drought. In recent years, attempts to quantify the impacts of flash drought via precipitation, soil moisture, evapotranspiration, and temperature indicators have proliferated. What has rarely been quantified is what the rapid decline in vegetation health amid flash drought looks like through remote sensing. This is because vegetation health indices like the Normalized Difference Vegetation Index (NDVI) are derived from the visible and infrared regions of the electromagnetic spectrum and …

A Novel Method Of Protein Purification Using Hedgehog Proteins As An Inducible, Self-Cleaving Tag, Antonia Kladias

Undergraduate Honors Theses

Because removing extraneous purification tag sequences from native proteins can be challenging and costly, there is demand for simple all-in-one techniques that directly furnish a tagless, functional protein-of-interest (POI). Current tagless purification systems are based on intein biochemistry; however, intein-based purification requires expensive, specialized resins and the POI often must be fused to the intein’s C-terminus. In this thesis, I present a novel approach for tagless POI purification in which the Drosophila melanogaster hedgehog protein catalytic domain (HhC) is repurposed as a small-molecule inducible, self-cleaving element dubbed Gtag. With Gtag, the POI is fused to the N-terminus of HhC/Gtag with …

Landscape Connectivity And Wildlife Access To Water Across An International Border: Barriers And Opportunities For Facilitating Transboundary Movement, Bogdan Chivoiu, Erin L. Koen, Michael J. Osland, Christopher A. Gabler, Jerald T. Garrett, Ernesto Reyes, Stephanie A. Bilodeau, Mitch A. Sternberg, Jude A. Benavides, James Martinez

School of Earth, Environmental, & Marine Sciences Faculty Publications

Rapid global acceleration in the construction of physical barriers along international borders has greatly influenced biodiversity and animal movement. Physical barriers can fragment landscapes, hinder access to essential resources, impact long-distance migrations, and inhibit dispersal and gene flow. The effects of physical barriers on animal movement and landscape connectivity can be exacerbated in dryland environments where access to water is a limiting factor. In recent decades, the construction of border barrier infrastructure has accelerated along the international boundary between the United States and Mexico. Here, we used a landscape connectivity model to investigate the effects of barriers on wildlife access …

Isolation, Purification, And Characterization Of Α-Galactosidase From Watermelon (Citrullus Lanatus), Christopher Henley Jr.

Chemistry & Biochemistry Undergraduate Honors Theses

The enzyme α-galactosidase is a type of glycosidase that removes galactose sugar units from larger molecules in cells. Compounds that inhibit glycosidases have been useful for understanding the structure and function of the enzymes they inhibit, and some have been used to treat certain diseases. Using inhibitors of α-galactosidase to study its characteristics and mechanisms may provide insights into its role in disease and its general utility. Advances in fields such as agriculture, sustainable fuels, and biomedicine may be facilitated by inhibition studies of α-galactosidase, but the current library of known inhibitors is relatively lacking. Obtaining α-galactosidase enzymes from chemical …

Enrichment Of The Thermophilic Archaea Gearchaeales And Calditenuis In Lab Culture, Walter Saldivar

Electronic Theses, Projects, and Dissertations

Numerous microbes on Earth have yet to be grown in pure cultures and studied in the laboratory. Cultivation-independent genomic methods, such as metagenomics, can help us predict their metabolic capabilities, but cultivation remains valuable for testing these predictions. These uncultivated microbes are very diverse, especially within hot springs. Examples of these uncultivated microbes include the genus Calditenuis (formerly Aigarchaeota Group 1) and the order Gearchaeales; they are often abundant in terrestrial hot springs such as Great Boiling Springs (GBS) in Nevada. Previous work allowed for the establishment of laboratory enrichment cultures inoculated from sediments of GBS containing Calditenuis and …

Understanding The Role Of Toxs As A Bile Sensing Component Of The Toxrs Virulence Regulatory System In Vibrio Spp., Minje Kim

Dartmouth College Ph.D Dissertations

Pathogenic Vibrio bacteria, such as V. cholerae and V. parahaemolyticus, colonize in the human small intestine to cause severe gastrointestinal disease. During the infection, these bacteria encounter bile salts, antimicrobial cholesterol metabolites secreted into the intestine. Pathogenic Vibrio species have evolved to utilize bile salts as signals to regulate virulence. The signaling depends in part on ToxRS, a conserved co-component transmembrane transcription regulator. ToxRS consists of the transcription factor ToxR and its membrane-tethered binding partner ToxS. ToxS is required for ToxR stability and full transcriptional activity. Although bile salts are known to influence ToxRS-dependent virulence gene expression, the molecular …

Comparing Awssi And Traditional Winter Metrics For Predicting Overwinter Survival Of Juvenile Walleye (Sander Vitreus), Camille N. Shifrin

Honors Program: Senior Projects (Public)

Winter conditions are an important driver of recruitment variability in freshwater fishes, yet winter severity is often characterized using single climate metrics. These simplified approaches may not capture the cumulative stress experienced by fishes during winter. The Accumulated Winter Season Severity Index (AWSSI) integrates multiple components of winter climate and may therefore provide a more biologically relevant indicator of overwinter survival. In this study, we compared AWSSI with traditional winter severity metrics to explain interannual variation in overwinter survival of juvenile Walleye (Sander vitreus) in Harlan County Reservoir, Nebraska. Model comparisons using Akaike’s Information Criterion (AIC) indicated that …

Un-Packing The Pantry: Evaluating And Addressing Nutritional Gaps In Full Circle Food Pantry Service, Gweneth J. Keith-Powell

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Arkansas has the highest food insecurity rate in the U.S., and college students are disproportionately food insecure. Food insecure populations tend to have worse nutrition and face poorer health outcomes, exacerbating the economic disparities they already face. The purpose of this study was to analyze specific food pantry usage trends, healthy diet access barriers, and processed food consumption drivers of Full Circle Food Pantry clients at the University of Arkansas as they related to food insecurity and nutrition disparities, as well as design a targeted project to improve nutation in an underserved client demographic. Findings supported existing literature regarding lower …

The Influence Of Additional Zinc Supplementation During Gestation On The Trace Mineral Concentrations Of Tissues, Milk, And Calf Serum At Birth, Hunter Miller

Animal Science Undergraduate Honors Theses

Minerals are known to play a key role in the immune system, growth, and development of animals. An important part of a calf's life is receiving colostrum immediately after birth, which provides the calf with immunoglobulins and necessary nutrients that are required. Furthermore, the gestation period is another very important aspect of the calf's life where they can take in the necessary nutrition. This study compared how two different supplements fed during the gestation period ultimately affected the mineral concentrations of the colostrum, placenta, calf plasma, and cow liver. The supplements that were provided were a 1) control that provided …

Clawing Our Way To Inclusion: Identifying Minority Students’ Barriers To Entering The Veterinary Medicine Profession, Danielle Reeves

Animal Science Undergraduate Honors Theses

Veterinary services are being utilized more each year as pet owners are increasingly viewing and treating their pets like family members. Due to this changing perspective, the veterinary profession has grown significantly. Yet, despite this change, there is a lack of ethnic/racial diversity within the veterinary field. The purpose of this study was to determine the factors and/or barriers associated with minority students' desire or lack of desire to pursue a career in veterinary medicine. This study used an online survey tool to collect qualitative and quantitative data from 423 undergraduate students at the University of Arkansas during the spring …

The Effect Of Blue-Green Light On Behavioral Repertoire And Fear Responses In Broiler Chickens, Addie Walker

Animal Science Undergraduate Honors Theses

The broiler chicken industry has increased the number of birds produced each year,

making the mitigation of stressors that affect broiler health and meat quality increasingly

important. New management strategies, like lighting protocols, could help combat stressors and

promote behavioral indicators of positive welfare. This study compared the effects of blue-green

and white light on broiler fear response using a tonic immobility test and behavioral repertoire in

the home pen using continuous focal sampling. Day-of-hatch male broiler chicks (N=600) were

randomly divided into 12 pens (n=50 chicks/pen). The pens had either a white LED light

(control, n=6) or a blue-green …