Life Sciences Commons^™

Investigating The Role Of Spinal Motoneuron Organization In Human Motor Control, Rachel I. Taitano

Graduate Theses, Dissertations, and Problem Reports (ETD)

Mechanisms of voluntary motor control are complex and require inputs via cortical centers, peripheral sensory systems, and spinal inputs such as central pattern generators. It is hypothesized that control is simplified via utilization of motor primitives, which may rely on structures within the spinal cord, however this remains unknown in both human and non-human primates. The goal of this dissertation is to characterize muscle activity in the upper extremity in relation to the corresponding anatomical organization of spinal motoneurons to provide insight into how primitives are both organized and activated to produce movement.

The first aim of this work was …

Examining The Role Of Microbial Communities In Soil Carbon Cycling Across Levels Of Complexity, Chansotheary Dang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Microorganisms provide the foundation for many ecosystem processes and are important drivers of carbon and nutrient cycling. The advancement of next generation sequencing has allowed researchers to lift open the lid on the ‘black box’ in microbial ecology. While previously unculturable microbes can now be characterized with the 16S rRNA gene, answering ‘who’s there?’ is only part of the challenge. Hidden inside the ‘black box’ remains the question, ‘who’s doing what?’. Recent development in trait-based methods like quantitative stable isotope probing (qSIP) equipped microbial ecologists with the tool to connect taxon-specific traits to ecosystem processes. Despite the growing body of …

Performance And Physiological Impacts Of Branched-Chain Amino Acid And Tryptophan Ratio Variations In Turkey Starter Diets Utilizing Concentrated Corn Proteins, Emily Blair Estanich

Graduate Theses, Dissertations, and Problem Reports (ETD)

In Chapter 2, a study was designed to evaluate the effects of varying dietary branched-chain amino acids (BCAA) ratio in corn and soybean meal-based turkey starter diets. The BCAA leucine, isoleucine, and valine are considered indispensable amino acids needed for energy and stimulation of muscle protein synthesis via the mammalian target of rapamycin (mTOR) pathway. Imbalanced BCAA ratios can lead to antagonism and degradation of limiting BCAA, particularly in diets with excess leucine. Concentrated corn proteins contain high levels of leucine and can alter BCAA requirements; however, crystalline BCAA may be added to correct these ratios. This study aimed to …

The Function Of Protein Glutamylation In Vision, Rawaa Aljammal

Graduate Theses, Dissertations, and Problem Reports (ETD)

Posttranslational glutamylation of protein has emerged as a novel candidate for cellular integrity. In a dynamic process, Tubulin Tyrosine Ligase Like proteins (TTLLs) introduce glutamate groups to their substrates, while Cytosolic Carboxypeptidases members (CCP1-CCP6) remove these glutamate groups. The outcome of this interplay is a wide range of substrates; each is glutamylated to a level crucial for its function.

Protein glutamylation is particularly abundant in neurons and in the axoneme of cilia and flagella. This distribution, along with the correlation between imbalanced glutamylation levels and compromised cellular functions, underscores the significance of protein glutamylation in maintaining cellular viability. However, the …

Structural And Functional Consequences Of Pde6 Prenylation In Rod And Cone Photoreceptors, Faezeh Moakedi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Phosphodiesterase-6 (PDE6) serves as a pivotal component in the phototransduction pathways of both cone and rod photoreceptors. In cones, PDE6 consists of tetrameric subunits: inhibitory (γ') and catalytic (α'). The catalytic subunit, PDE6α', contains a C-terminal prenylation motif. Deletion of this motif is associated with achromatopsia (ACHM), a form of color blindness. The mechanisms underlying the disease and the roles of PDE6 lipidation in vision remain elusive. Meanwhile, rod PDE6 is composed of α and β catalytic subunits and γ inhibitory subunits, with alterations in the C-terminal "prenylation motif" of PDE6β linked to retinitis pigmentosa (RP) pathology. In this comprehensive …

Effects Of Dietary Supplementation Of A Blend Of Saccharomyces Cerevisiae, Multiple Live Probiotic Bacteria, And Their Fermentation Products On Performance, Health, And Rumen Bacterial Community Of Newly Weaned Beef Steers During A 56-D Receiving Period, Emily Treon

Graduate Theses, Dissertations, and Problem Reports (ETD)

We examined the effects of a blend of Saccharomyces cerevisiae, multiple live probiotic bacteria and their fermentation products on performance, health, and the ruminal bacterial community of newly weaned beef steers during a 56-day receiving period. Forty newly weaned Angus crossbred steers (221 ± 25.6 kg BW; 180 ± 17 d of age) were stratified by body weight into four pens (10 steers per pen) such that each pen had a similar average body weight at the beginning of the experiment. The pens were randomly assigned to receive a corn silage basal diet (CON; n = 20) or the …

An Inhibitory Recurrent Network In The Olfactory System, Farzaan Salman

Graduate Theses, Dissertations, and Problem Reports (ETD)

Neuromodulatory circuits are a necessary component of neural flexibility as they are able to act differentially depending on the receptors expressed by their downstream targets. Identifying the synaptic partners of modulatory neurons and determining the neurotransmitter and receptor content of these partners is necessary to identify the rules governing neuromodulatory circuits. In this study, I characterized the circuit of the contralaterally projecting, serotonin-immunoreactive deutocerebral neurons (CSDns), the sole synaptic source of the neuromodulator serotonin in the olfactory circuit of Drosophila melanogaster, by identifying the strongest synaptic partners of the CSDns, and the expression of genes encoding neurotransmitters and receptors of …

A Balancing Act: Microrna Mediated Insect-Bacterial Homeostasis And The Tsetse Fly, Mason Hubbard Lee

Graduate Theses, Dissertations, and Problem Reports (ETD)

Microbial symbioses are ubiquitous across all kingdoms of life with broad and diverse impacts on the evolution of species. The sum of all microbes living in, on, or otherwise in close association with a host form the microbiota. In some cases, the development of a stable microbial association seems to have been necessary for the specialization of diet, as can be observed in numerous insect species, especially wood-eating, sap-feeding, and blood-feeding organisms. For the medically and economically tsetse fly (family Glossinidae), the mutualistic bacteria Wigglesworthia glossinidia is required for proper reproduction and supplementation of nutrients that the fly does not …

Sars-Cov-2 Immunogenicity Models Inform Novel Strategies That Can Improve Mrna Vaccines, Katherine S. Lee

Graduate Theses, Dissertations, and Problem Reports (ETD)

The onset of the 2020 COVID-19 pandemic, caused by the novel coronavirus SARS-CoV-2, issued a call to action in the fields of biomedical science and public health to implement strategies to contain and protect against the viral threat. In record times, pharmaceutical companies produced antiviral therapies and novel mRNA vaccines that were approved by the FDA for human use. With time, these vaccines were able to assist in ending the pandemic. However, time also showed the limits of mRNA vaccine induced immunity. Despite antibody responses being initially robust, titers dramatically wane with time and are limited in cross-neutralizing ability. As …

Exploring Long-Term Patterns: Black Bass Tournament Fishery And Population Trends In West Virginia's Navigable Rivers, Alex J. Benecke

Graduate Theses, Dissertations, and Problem Reports (ETD)

Black bass Micropterus spp. are popular sport fish in West Virginia’s navigable rivers. In recent years, anglers have expressed concerns about a potential decline in fishery quality. To investigate these claims, we evaluated whether fishery quality has declined compared to earlier periods and whether population trends correspond to angler catch rates. Specifically, we aimed to (1) examine changes in species catch over time and during key periods, such as tournament and spawning seasons; (2) describe the distribution of black bass species across pools and habitat types; and (3) assess the outcomes of previous stocking efforts. To address these objectives, we …

Cerebellar Feedback Effects On Responses To Conspecific Signals Of Different Frequencies In The Electrosensory System, Elora K. Shinn

Graduate Theses, Dissertations, and Problem Reports (ETD)

Sensory systems in animals have evolved to translate physical stimuli into neural representations that, in turn, guide behavior. Feedback is critical in these processes, allowing organisms to filter redundant information and respond effectively to relevant stimuli. In humans, for example, the cerebellar flocculus provides feedback to the vestibulo-ocular reflex to stabilize eye movements during body rotation. In bats, the feedback during echolocation helps prioritize essential signals from the environment. In weakly electric fish, cerebellar feedback helps filter out redundant low-frequency modulations caused by conspecifics, enabling them to detect prey and other relevant signals. However, the influence of cerebellar feedback on …

Physical Activity, Anxiety, Depression, And Coping In Turkish Men And Women During The First Wave Of Covid-19, Bijen Filiz, Funda Coşkun Özyol, Bengü Güven, Ezel Nur Korur, Yılmaz Yüksel, Cavit Işık Yavuz, Kele Ding, Jingzhen Yang, J. Larry Durstine Phd, Facsm, Faacvpr, Fnak, Ming-Kai Chin, Gıyasettin Demirhan

Faculty Publications

A need exists to better understand the relationships between COVID-19, coping behaviors, physical activity and stress, and COVID-19’s impact on way of life. A cross-sectional study design was used to examine adult physical activity, hope, depression, anxiety, and coping status by gender during the COVID-19 pandemic, and to determine the impact of these variables on the coping process. The study also examined the effect of gender on the relation between physical activity and dependent variables. A global survey instrument was used in this study, including 1,400 Turkish adults. This study identified significant gender-based differences regarding physical activity, hope, depression, anxiety, …

Atm-/-Ung-/- Mice Present Reduced Levels Of Switched Immunoglobulin Isotypes Igg1 And Igg3, Lyric M. Haughton

Dissertations and Theses

B cells excise and recombine the immunoglobulin heavy chain gene locus during class switch recombination (CSR). CSR is mediated by activation induced cytidine deaminase (AID) and results in a new immunoglobulin isotype that B cells will secrete and present. AID produces mutations that convert cytosines to uracils within the intronic switch regions that precede and follow the target immunoglobulin isotype coding sequence. To resolve the mutations, B cells conduct either base excision repair (BER) or mismatch repair (MMR). Inactivating genetic mutations in BER or MMR reduce CSR. For example, a knock-out of uracil DNA glycosylase (UNG) causes a 50% reduction …

Synthesis Of Novel 5-Aryl 2’-Deoxyuridine And 2’-Deoxycytidine Analogues, Kevin E. Persaud

Dissertations and Theses

Briefly, the following report details a synthetic route to prepare 5-phenyl-2’-deoxycytidine analogues. This multistep synthesis began with silyl protection of the 3’- and 5’-hydroxyl groups of 5-iodo-2’-deoxyuridine. Next, the installation of a phenyl ring at the C5 position of the nucleobase via a Suzuki-Miyaura cross-coupling reaction, yielding 5-phenyl-2’-deoxyuridine (5-PdU). After that, modification of the obtained 5-PdU at the C4 position was performed with benzotriazole-1-yl-oxy-tris-(dimethylamino)-phosphonium hexafluorophosphate (BOP, a peptide-coupling agent) and a base (cesium carbonate) to activate the amide group of the uridine nucleobase for subsequent displacement with a variety of amines. Modification of the C4 position resulted in protected 5-phenyl-2’-deoxycytidine …

The Effect Of Nanoconfined Liquid Properties On The Water-Responsive Behavior Of Bacterial Cell Walls, Seungri Kim

Dissertations and Theses

Water-responsive (WR) materials have the ability to mechanically swell and shrink in response to changes in relative humidity (RH). These WR materials are used by many biological systems to perform essential tasks; for example, pinecones use WR materials to release their seeds in dry environments, and wheat awns open and close to propel seeds into the soil, driven by daily RH changes. The WR actuation of some biomaterials is extremely powerful, for example Bacillus subtilis cell walls display record-high actuation energy and power densities of 72 MJ m^-3 and 9.1 MW m^-3, surpassing those of all existing …

Developing Methods For Analysis Of Chiral Small Molecules And D-Amino Acid Containing Peptides, Joshua I. Putman

Chemistry & Biochemistry Dissertations - Archive

This dissertation covers the development of methods to analyze chiral small molecules and d-amino acid containing peptides. The first section covers the development of liquid chromatographic chiral screening approaches for newly synthesized chiral molecules. The next part of the dissertation covers methodologies for the analysis of d-amino acid containing peptides. Lastly the bacterial degradation of three commonly used pesticides by bacteria harvested from Colorado potato beetles (Leptinotarsa decemliniata) is presented.

Twelve new azole compounds and eleven racemic ethanolamine derivatives were synthesized. These twenty-three compounds were evaluated using eight chiral columns, four macrocylic glycopeptides, a cyclodextrin derivative …

Capture History Data From Hair Snare Sampling Of Wild Pigs In Mississippi, Tyler S. Evans, Eric T. Hileman, Melanie R. Boudreau, Bronson K. Strickland, Raymond B. Iglay

CFR Publications

Capture histories of wild pigs (Sus scrofa) identified using nuclear DNA markers from hair snare samples activated on the Sam D. Hamilton Noxubee National Wildlife Refuge in Mississippi between 2021 and 2022. Hair snares were active for 8 weeks (occassions) with non-grain attractants placed at the center of each snare. Dat includes unique pig identifiers (Pig_ID), capture histories (Capture_Occassion), and associated capture year (Group).

Data From: Phylogenomic Species Delimitation Of Studfishes (Fundulidae: Fundulus): Evidence For Cryptic Species In Agreement With The Central Highlands Vicariance Hypothesis, Kayla M. Fast, Peter J. Hundt, Zachariah D. Alley, Michael W. Sandel

CFR Publications

The Central Highlands ecoregion of the eastern United States represents a hotspot of freshwater biodiversity, with replicated patterns of vicariant speciation east and west of the Mississippi River. Previous phylogeographic investigation of the studfishes (Fundulus subgenus Fundulus) revealed evidence for vicariant speciation in the Central Highlands, but data were limited to a small number of gene sequences generated with Sanger sequencing. We used double digest restriction-site associated DNA sequencing (ddRADseq) to improve resolution of phylogeographic patterns and better characterize population genetic variation. Our sample design included individuals from the Fundulus catenatus species group (F. catenatus, F. bifax, …

Zebrafish Drug Screening Identifies Erlotinib As An Inhibitor Of Wnt/ Β-Catenin Signaling And Self-Renewal In T-Cell Acute Lymphoblastic Leukemia, Majd A. Al-Hamaly, Anna H. Cox, Meghan G. Haney, Wen Zhang, Emma C. Arvin, Shilpa Sampathi, Mary Wimsett, Chunming Liu, Jessica S. Blackburn

Markey Cancer Center Faculty Publications

The Wnt/β-catenin pathway’s significance in cancer initiation, progression, and stem cell biology underscores its therapeutic potential. However, the clinical application of Wnt inhibitors remains limited due to challenges posed by off-target effects and complex cross-talk of Wnt signaling with other pathways. In this study, we leveraged a zebrafish model to perform a robust and rapid drug screening of 773 FDA-approved compounds to identify Wnt/β-catenin inhibitors with minimal toxicity. Utilizing zebrafish expressing a Wnt reporter, we identified several drugs that suppressed Wnt signaling without compromising zebrafish development. The effi- cacy of the top hit, Erlotinib, extended to human cells, where it …

Bacteria Associated With Parthenium Hysterophorus Root Exudate Influence Olfactory Oviposition Responses Of Anopheles Gambiae, Trizah K. Milugo, Baldwyn Torto, David P. Tchouassi

All Peer-Reviewed Publications

Introduction: Previously, we documented that the malaria vector Anopheles gambiae responds to volatile emissions from the root exudate water of the invasive plant, Parthenium hysterophorus. However, the origin of the volatiles remains to be investigated. Here, we isolated bacteria from the root exudate water of the plant, test the influence of their volatiles in gravid An. gambiae oviposition, and examined relationships between volatile profiles and oviposition. Methods: Bacteria from root exudate water of P. hysterophorus were isolated using culture on Luria Bertani medium and identified by sequencing the 16S rRNA gene. Cultures of individual isolates were evaluated for egg laying …

Developmental Stress Signaling And Substance Use: Cortisol Reactivity Moderates The Effect Of Early Life Adversity On Alcohol Misuse Behaviors Among College Students, Keeley Lariviere

CMC Senior Theses

Stress-motivated drinking is common among college students facing increased independence and novel stressors. Early life adversity (ELA) as well as individual variation in neuroendocrine stress signaling significantly increase risk for alcohol misuse. Research on the relationships between ELA and the physiological stress response system, suggest that a dampened stress response may mediate the relations between ELA and alcohol misuse. However, other research has suggested that rather than acting as mediator, stress reactivity may interact (moderate) the relations between ELA and alcohol misuse. This study examined the associations between ELA, cortisol reactivity to an acute stressor, and self-reported alcohol misuse in …

Harnessing Antagonistic Pleiotropy: Tolc-Dependent Coliphages Can Drive Reduced Antibiotic Resistance In E. Coli, Cooper Mckenna

CMC Senior Theses

The rise of multidrug-resistant (MDR) bacterial pathogens has been a growing concern in healthcare around the world, and bacteriophage (phage) therapy is a promising method to combat MDR infections. One defense mechanism of E. coli against antibiotics is the TolC-AcrAB efflux pump. At the same time, some phages use TolC as a surface receptor to infect the cell. This puts TolC at a crossroads in which it is beneficial to the bacteria to protect against antibiotics but harmful by allowing phage infection, creating the potential for evolutionary trade-offs. Previous research has identified only three TolC-dependent phages and shown phage-resistant E. …

Mental Imagery Contributes To Loss Aversion By Amplifying Negative Emotions, Daniel Kroshchuk

CMC Senior Theses

Defined as the experience of sensory information without the presence of external stimuli, mental imagery is thought to play a role in memory, emotional regulation, and decision-making. Recent studies suggest that mental imagery varies widely across the general population, with approximately 2-4% of individuals having a reduction or complete absence of visual imagination, a phenomenon known as aphantasia. Individuals with aphantasia show reduced emotional arousal to fear-inducing imagery, raising the question of how variation in imagery affects cognitive processes that are influenced by emotion. Specifically, in economic decision-making it has been shown that the prospect of loss triggers negative emotions, …

Gut Dysbiosis Correlates With Covid-19 Severity, Ednita Escobar

CMC Senior Theses

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) impacts not only respiratory but also gut and oral microbiomes, influencing the manifestations of COVID-19. Each person’s unique microbiome consists of microorganisms such as bacteria, fungi, and viruses, some of which are symbiotic and others potentially harmful. Alterations in the gut microbiome, specifically, can affect the severity and symptoms of COVID-19. A review of studies indicate a pattern of gut dysbiosis in COVID-19 patients characterized by a decrease in beneficial microbiota and/or an increase in opportunistic pathogens. This gut imbalance correlates with disease severity, suggesting that the gut microbiome plays a significant role …

Bio-Bust: Investigating Biotech Stock Factors Contributing To Abnormal Returns In The Wake Of Silicon Valley Bank's Failure, Spencer Kent

CMC Senior Theses

Following the unprecedented collapse of Silicon Valley Bank (SVB) in March 2023, this study explores abnormal stock price reactions within the biotechnology sector. As the chosen financial institution for countless Silicon Valley-type technology and healthcare firms, SVB's failure had a profound impact on small to mid-sized biotech companies. Analyzing a dataset of 180 biotech firms during a two-day event window over SVB’s collapse, I investigate whether exposure to SVB, or other factors, was the primary contributor to negative abnormal stock price reactions, considering variables such as the percentage of cash held at SVB, whether a firm maintained an active SVB …

C. Compactum Acts As A Comprehensive Climate Archive And Ecological Foundation In The Labrador Sea, Sadie Heckman

CMC Senior Theses

Clathromorphum compactum, a species of crustose coralline algae (CCA), is incredibly valuable for the future of high latitude ocean health, both as a comprehensive archive of changing ocean conditions, and ecologically as a foundational species for promoting biodiversity. Previous work establishes C. compactum as an effective climate proxy, and its life history provides several advantages for this use. C. compactum grow in nongeniculate, generally radial formations on hard substrates, over a wide distribution in mid-to-high latitude oceans and at subtidal depth ranges. Indeterminate growth leads to extreme longevity in C. compactum (Halfar et al., 2008), and growth rates are relatively …

What Are We Most Curious About? Understanding The Relationship Between Curiosity And Marginal Knowledge, Alexis Lee

CMC Senior Theses

There are several competing theories about the relationship between curiosity and metacognitive judgment, or one’s assessment of their own knowledge. Novelty theories say that curiosity is highest for wholly unknown information; complexity theories say that curiosity is highest for moderately unknown information; and the Region of Proximal Learning (RPL) theory says that curiosity is highest for almost-known information. The present study aimed to address how curiosity differs within marginal knowledge (MK), memory content that is available but not accessible, across two experiments. In both experiments, participants responded to 100 short-answer general knowledge questions, selecting a phenomenological category to represent their …

Embryonic Exposure To Sodium Perchlorate Disrupts Organ Development In Mice, Kyle Bouten

All Graduate Theses, Dissertations, and Other Capstone Projects

Perchlorate is an endocrine disrupting compound (EDC) commonly used for its oxidative properties. Perchlorate has been detected in many industrialized countries in drinking water, soil, foods, and breast milk. Perchlorate competitively inhibits the uptake of iodide into the thyroid follicles via the sodium/iodide symporter (NIS), thus reducing thyroid hormone synthesis. Perchlorate has many conflicting results in the toxicological effects that perchlorate has on organ development in model fishes, but much less work has been done on mammals. In the present study, I examined the morphological effects of environmentally relevant concentrations (0, 10, and 100ppm) of sodium perchlorate on the thyroid, …

Mitochondrial Dna Variation In Honey Bee (Apis Mellifera) Colonies From Arkansas, U.S., Allen Szalanski

Entomology and Plant Pathology Faculty Publications and Presentations

This study characterized the mitochondrial DNA (mtDNA) genetic variation in Arkansas honey bee, Apis mellifera L., by sequencing a portion of the mitochondrial cytochrome oxidase (COI-COII) intergenic region). The samples were primarily of hobbyist-managed origin (n=180), as well as 32 feral colonies and two swarms. Of the 214 honey bee colonies and swarms sampled, 23 haplotypes were observed. The haplotypes were from the: A (African) (1.87%); C (South eastern European) (92.52%); M (Northern and Western European) (3.27%); and O (Near East and Middle East) lineages (2.34%). Six C lineage haplotypes were predominantly detected (n=189, 88.31%), all of which are common …

Discovery: The Student Journal Of Dale Bumpers College Of Agricultural, Food And Life Sciences - Volume 25 2024, Several Authors

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.