Life Sciences Commons^™

The Effect Of Conspecific Cues And Neighborhood Effects On Bee Foraging Behavior, Eva Sofia Horna Lowell

Electronic Theses and Dissertations

Foraging bees use social information (e.g. presence of absence of other bees) to assess the quality of flowers when choosing a flower to visit. My research tests how bees choose to visit a particular flower once they have been recruited to a flower patch. I tested if neighborhood effects, or the relative number of bees on neighboring flowers compared to a focal flower, affected to which flower a foraging honey bee visited. I also conducted a meta-analysis to test whether bees in the super-family Apoidae are more likely to visit a flower occupied by a con- or heterospecific bee or …

Characterization Of Vps41 And Its Role In The Regulated Secretory Pathway, Christian Henry Burns

Electronic Theses and Dissertations

Insulin secretory granules (SGs) mediate the regulated secretion of insulin, which is essential for glucose homeostasis. The basic machinery responsible for this regulated exocytosis consists of specific membrane proteins present both at the plasma membrane and on insulin SGs. The protein composition of insulin SGs thus dictates their release properties, yet the mechanisms controlling insulin SG formation, which determines this molecular composition, remain poorly understood. VPS41, a component of the endolysosomal tethering HOPS complex, was recently identified as a cytosolic factor involved in the formation of neuroendocrine/neuronal granules. We now find that a stable pool of VPS41 exists outside of …

Proximate And Ultimate Consequences Of Stressed-Induced Maternal, Paternal, And Joint Parental Effects In A Changing World, Whitley Rayen Lehto

Electronic Theses and Dissertations

Parental experience can alter the developmental and rearing environments of offspring, resulting in parental effects on offspring traits. I addressed the consequences of stress-induced maternal, paternal, and joint parental effects from both ultimate (ecological/evolutionary) and proximate (physiological/epigenetic) perspectives. I used a full-factorial design in which threespine stickleback (Gasterosteus aculeatus) mothers, fathers, both, or neither were exposed to a model predator at developmentally appropriate times to test for predator-induced maternal, paternal, and joint parental effects on daughters’ mating behavior and egg glucocorticoids (stress hormones) and on offspring gene expression. Maternal and paternal predator exposure independently yielded daughters who preferred …

Qualitative And Quantitative Fitness Consequences Of Advanced Maternal Age, Claudia Jean Hallagan

Electronic Theses and Dissertations

Parental age can affect offspring fitness across taxa and through various mechanisms. However, the effect(s) of advanced maternal age on offspring, particularly in insects, has not been comprehensively reviewed making it difficult to draw conclusions about the effects of advanced maternal age on offspring in insects. In my first chapter, I reviewed maternal age literature and found overall negative effects of advanced maternal age on offspring fitness. However, results vary depending on which fitness measures were used, the life stages at which offspring were measured, and the experimental design of the study. In my second chapter, I conducted an experiment …

Development Of A Hek293 Cell Line To Show Inhibition Of Tau Aggregation, Justin Ray Shady

Electronic Theses and Dissertations

Intracellular deposition of aggregated tau is the hallmark of several different tauopathies, the most widespread of these being Alzheimer's disease. Tau is a highly soluble, intrinsically disordered, microtubule associated protein. Tau's native function is to stabilize microtubule formation in the axons of neurons. Post translational modification such as hyperphosphorylation as well as several familial mutations allow tau to nucleate and form fibrils. These fibrils can recruit healthy monomers onto their ends in a fashion described as template-assisted growth. Tau has 6 isoforms that vary by the inclusion or exclusion of two N-terminal repeats and the inclusion or exclusion of the …

Photoassisted Synthesis Of Complex Polyheterocycles Via Esipt-Driven Dearomative Intramolecular Cycloadditions, Dmitry Kuznetsov

Electronic Theses and Dissertations

This research is focused on the development of novel photoassisted synthetic methodologies that provide straightforward access to complex and diverse libraries of polyheterocycles from modularly assembled precursors. All methods are based on the dearomative cycloadditions between two components: (i) o-azaxylylenes, generated by the excited-state intramolecular proton transfer, and (ii) tethered arene groups.

We have demonstrated the synthetic utility of four new photoinduced processes that yield complex products amenable for post-photochemical modifications:

• [4+4] Cycloaddition of o-azaxylylenes to 1,3,4-oxadiazoles with subsequent dinitrogen extrusion. This reaction furnishes compounds outfitted with epoxide fragments, which undergo ring-openings with various nucleophiles; furthermore, the oxidized products …

Mechanistic Insight Into Tau Fibril Cross-Seeding Barriers: Structural Order And Disorder, Hilary Ann Weismiller

Electronic Theses and Dissertations

Filamentous deposition of microtubule-associated protein tau is a hallmark for a number of neurodegenerative diseases collectively termed tauopathies. While tau fibrils are directly linked to the etiology and pathogenesis of these diseases, fibril morphology and their phenotypic presentation can be quite disparate. Alternative splicing of tau results in two main isoform groups, four-repeat (4R) tau and three-repeat (3R), identified by their number of microtubule binding repeats. Some diseases show deposition of both 4R and 3R isoforms, while others show preferential deposition of only one type. The conformational templated growth scheme and trans-synaptic spreading of fibrils is influenced by fibril conformation. …

Translation Of Partially Decayed Messenger Rnas In Yeast, Ana Luisa Franklin

Electronic Theses and Dissertations

Flaviviruses are positive-strand single-stranded RNA viruses that are known to form pseudo-knot RNA structures that halt the progression of 5’→3’ exonuclease Xrn1. We show that these viral Xrn1-resistant structures (xrRNAs) can be used to protect specific homologously-expressed messenger RNAs from 5’→3’ degradation. We investigated the effects of addition of xrRNAs, artificially-installed into the intergenic region of bicistronic mRNA reporters, in the observed levels of protein expression in yeast. The reporters also contain an internal ribosome entry site from the cricket paralysis virus (CrPV IRES) to allow for cap-independent translation of the decay-protected gene, LacZ, encoding the enzyme β-galactosidase. Through …

New Insights Into Mycofactocin Biosynthesis, Structure And Function, Richard Selorm Ayikpoe

Electronic Theses and Dissertations

Mycofactocin is a putative ribosomally synthesized and post-translationally modified peptide (RiPP)-derived redox cofactor. Its biosynthesis is accomplished through the dedicated actions of the products of six conserved genes, mftABCDEF. The mycofactocin pathway is one of the most widely distributed RiPP systems in bacteria however, this distribution is heavily skewed towards the Mycobacteria genus including human pathogenic variants such as M. tuberculosis and M. ulcerans. Gene expression studies have demonstrated the essentiality of the pathway in the ability of M. tuberculosis to utilize the host's cholesterol as sole carbon source during latency. However, the biosynthesis, structure and physiological function …

Characterization Of A Phosphomimetic Mutant Of The Als Associated Protein Tdp-43, Nicole Toro

Electronic Theses and Dissertations

Trans-activation response (TAR) DNA-binding protein 43 (TDP-43) is a natively dimeric 414-residue protein that is encoded by the human TARDBP gene that has important implications in the pathogenesis of the neurodegenerative disorders ALS, FTD, and CTE. TDP-43 has been found hyperphosphorylated and ubiquitinated in the aggregates of the affected neurons of these diseases. The discovery of the presence of TDP-43 positive inclusions in brain matter of patients with CTE has made repetitive brain injury a possible environmental stimulus for aggregation in TDP-43 proteinopathies. We expand upon the hypothesis that TDP-43 readily aggregates under agitation conditions and that the addition of …

Transgenerational Effects Of Maternal Age On Offspring Fitness In Crickets, Jacob D. Wilson

Electronic Theses and Dissertations

Advanced parental age is an important aspect of parental condition that can have both positive and negative effects on offspring fitness, and thus, parental age can be considered a parental effect. As a parental effect, parental age may affect a variety of offspring traits and may cascade to influence several generations of offspring. Given the complexities of studying both paternal and maternal age, we studied the effects of maternal age only. Using the Pacific field cricket, Teleogryllus oceanicus, we asked 1) does maternal age have influences over several generations of offspring and 2) does maternal age influence the reproductive …

A Mechanistic Study Of The Teratogenic Potential Of 4-O-Methylhonokiol (Mh) On Japanese Medaka (Oryzias Latipes), Santu Kumar Singha

Electronic Theses and Dissertations

An additional goal of this project was to characterize the Wnt/β-catenin signaling pathway to unravel the adverse potential of MH on the cardiovascular system (CVS). Our study suggested that MH-mediated cardiovascular injury may be caused due to upregulation of some major components of the Wnt/β-catenin pathway through expression of excessive pro-inflammatory mediators. Moreover MH decreased expression of ErbB3 and NRG-2 suggesting impaired cardiac structure. MH exposure caused a slow heartbeat blood occlusion absence of blood circulation decreased hatching efficiency and increased mortality in medaka embryos in a concentration- and time-dependent manner. MH might cause blood vessel occlusion by increasing the …

Examining The Role Of Reproductive Interference In The Decline Of Native Green Treefrogs Following Cuban Treefrog Invasions, Joseph Kennedy

Electronic Theses and Dissertations

Reproductive interference occurs when the mating behaviors of one species negatively impact the fitness of another species. It is of increasing interest in invasive species biology because the introduction of alien species often leads to novel sexual interactions with native taxa, which can contribute to their decline. I examined whether reproductive interference plays a role in the decline of native green treefrogs (Hyla cinerea) following invasions of Cuban treefrogs (Osteopilus septentrionalis) in the southeastern United States. The impetus for this study revolves around similarities in spectro-temporal features of Cuban treefrog courtship calls and green treefrog aggressive calls. The significance of …

Food Insecurity And Health Of International Students, Jamie Nichole Benefield

Electronic Theses and Dissertations

International college students may be at risk for suffering from food insecurity and poor health. The purposes of this study were to: 1) determine if the household adult food security status (HAFSS) differs between undergraduate and graduate international students (INSTUD) attending the University of Mississippi (UM); 2) establish if a statistically significant relationship exists between health (physical functioning (PF) , role limitations due to physical health (RLPH), role limitations due to emotional problems (RLEP), energy/fatigue (EF), emotional well-being (EWB), social functioning (SF), pain (P), and general health (GH) and HAFSS; 3) assess if health differs between INSTUD living in food …

Safety Assessment And Chemical Fingerprint Analysis Of Medicinal Plants Commonly Consumed As Herbal Teas; Rooibos (Aspalathus Linearis) And Moringa (Moringa Oleifera), Omer I. Fantoukh

Electronic Theses and Dissertations

The first chapter discusses the significance of natural products, safety challenges, and quality issues concisely. Specifically, the impact of herb-drug interaction on consumers and the quest for chemical markers for chemical fingerprinting development are provided. Rooibos tea (Aspalathus linearis) is a popular South African herbal tea enjoyed worldwide. Limited reports indicate the potential of rooibos tea to alter the activity of CYP450 isozymes. In chapter two, the phytochemical investigation of A. linearis resulted in the isolation and characterization of 14 phenolic compounds. Safety assessment of the phytochemicals through interaction with CYP, PXR, and P gp was conducted. The …

Identifying Transcription Co-Regulators Of Gcm/Repo In The Development Of Glia In Drosophila Melanogaster, Glendin Kostantinos Pano

Electronic Theses and Dissertations

The molecular mechanism mediating the differentiation of neural progenitors to either glia or neurons is guided by the gene glial cells missing (gcm), a master regulator of glial cell differentiation. Knockout of this transcription factor (TF) and its homolog gcm2 in the fruit fly Drosophila Melanogaster results in embryos that develop neurons in place of lateral glia. Conversely, overexpression of gcm in those neural progenitors results in embryos that have substantially fewer neurons and excess glia(Jones, et.al, 1995; Hosoya, et.al, 1995; and Vincent, et.al, 1996). Additionally, gcm has also been shown to be involved in the differentiation of blood …

Augmenting Land Cover/Land Use Classification By Incorporating Information From Land Surface Phenology: An Application To Quantify Recent Cropland Expansion In South Dakota, Lan Hoang Nguyen

Electronic Theses and Dissertations

Understanding rapid land change in the U.S. NGP region is not only critical for management and conservation of prairie habitats and ecosystem services, but also for projecting production of crops and biofuels and the impacts of land conversion on water quality and rural transportation infrastructure. Hence, it raises the need for an LCLU dataset with good spatiotemporal coverage as well as consistent accuracy through time to enable change analysis. This dissertation aims (1) to develop a novel classification method, which utilizes time series images from comparable sensors, from the perspective of land surface phenology, and (2) to apply the land …

Metabolic Effects Of 17a-Estradiol Are Growth Hormone Independent And Sex Specific, Silvana Sidhom

Electronic Theses and Dissertations

Aging is a major risk factor for metabolic syndromes and type two diabetes. With growing elderly populations worldwide and increasing incidence of age-related diseases there is a great need to develop pharmacological interventions that would delay aging and protect from age-related diseases. 17-alpha estradiol (17α-E2) is an epimer of the primary female sex hormone estradiol and has been shown to extend lifespan and downregulate markers of age-related metabolic dysfunction in male mice. Because 17α-E2 does not induce feminization in males it holds potential as a novel therapeutic in humans for age-related metabolic dysfunction. Importantly, we have previously shown that 17α-E2 …

Identification And Functional Characterization Of A Long Non-Coding Rna Associated With Prostate Cancer, Md Faqrul Hasan

Electronic Theses and Dissertations

Prostate cancer is the most common cancer in men in the western world. Although early stage prostate cancer is treatable late stage, more specifically, metastatic and drug resistant prostate cancers are mostly incurable. The failure of current treatments obligates the research community to explore novel areas in prostate cancer biology and find better therapeutic targets. Emerging evidences show that non-coding RNAs specifically long non-coding RNAs (lncRNAs) play regulatory roles in various cellular processes and are frequently dysregulated in cancer including prostate cancer. These aberrantly expressed lncRNAs mostly with unexplored genetic information may drive cancer progression. Previous studies done in our …

Development Of A Functional Testing Platform For The Sensory Segment Of The Neuromuscular Reflex Arc, Alisha Colon

Electronic Theses and Dissertations

Investigations of human biology and disease have been hindered by the use of animal models. The information obtained from such studies often results in clinically irrelevant results and drug trial failures. Additionally, several governing bodies have been formulating legislation to move away from animal models and toward more ethical and efficient testing platforms for drug discovery and cosmetic research. As an answer to these issues, "body-on-a-chip" systems have been a rapidly developing field which easily recapitulates in vivo functionality, providing a more relevant, repeatable, and ethical testing platform to better predict biology. These systems can be used as human-based testing …

Filling The Gaps: Common Bottlenose Dolphin (Tursiops Truncatus) Population Dynamics, Structure, And Connectivity Within Florida Panhandle Bays, Sounds, And Estuaries, Christina Toms

Electronic Theses and Dissertations

At the time of the Deepwater Horizon oil spill in 2010, very little was known about the inshore bottlenose dolphin (Tursiops truncatus) populations hit hardest by the spill. Without previous population demographic data impacts were challenging to assess. My dissertation was designed to build research capacity moving forward by helping to fill data gaps in the western Florida Panhandle. The first study presented here resulted in the first system-wide assessment of seasonal abundance, survival, and site fidelity patterns of bottlenose dolphins that inhabit the Pensacola Bay system. In contrast to a previous study that reported only 33 dolphins, results from …

Perceptions Of Health Coaching And Its Associations With Personality Style And Weight Loss In Meal Replacement Program Participants, Bailey Judith Larson

Electronic Theses and Dissertations

Purpose: To determine if personality style is related to perceptions of health coaching and if there is a relationship between perceptions of health coaching and the ability to lose weight. Methods: Data was gathered from approximately 2,000 MR program participants via an electronic survey. The Client Evaluation of Motivational Interviewing scale was used to determine if perceptions of health coaching affect the ability to lose weight. The Ten Item Personality Inventory was used to determine if personality style is associated with the perception of health coaching. Self-reported start weight and current weight were used to calculate percent of starting weight. …

Some Studies On Leaf Spot Of Oats And Triticale, Mohammed Abdullah Lashram

Electronic Theses and Dissertations

Oat is an important cereal crop, and it is considered to be among the highest used in cereal crops. It is considered among the healthiest grains due to the rich source of the soluble fiber, β-glucan that helps in lowering the cholesterol. Oat production and demand have increased considerably in the past few years due to its health benefits. South Dakota is ranked in the top three largest oat-producing states in the USA. Oat is relatively less susceptible to pest and diseases except for leaf diseases such as crown rust, Drechslera avenae leaf spot, and Stagonospora avenae leaf blotch. Leaf …

Development And Evaluation Of Vaccine Candidates For Senecavirus A, Bishwas Sharma

Electronic Theses and Dissertations

Senecavirus A (SVA) has been associated with several outbreaks of vesicular disease (VD) since 2014 in major swine-producing countries around the world. The virus causes VD that is clinically indistinguishable from foot-and-mouth disease (FMD) in pigs. Currently there are no commercial vaccines available for SVA. Here, we developed a live attenuated SVA strain by mutating a wild type SVA strain SD15-26 (wt SVA). The live attenuated virus, rSVA mSacII, replicated less efficiently in cell cultures in vitro and expressed lower amounts of VP1 and VP2 capsid proteins than wt SVA. Most importantly, the rSVA mSacII virus failed to induce clinical …

Influence Of Sporulation And Germination Behavior Of Bacillus Licheniformis On Microbial Quality Of Skim Milk Powder, Nancy Awasti

Electronic Theses and Dissertations

This dissertation includes modeling of sporulation and germination behavior of Bacillus licheniformis strains during raw milk holding, tracking the survival of sporeformers and spores of high sporulating Bacillus strain during skim milk powder manufacturing. In addition, preliminary studies were done to standardize a rapid spore detection technique by using ratiometric fluorescence. To understand the role of strain variability during raw milk holding conditions, population dynamics of two strains of Bacillus licheniformis, ATCC 6634 and 14580, were modeled as a function of temperature (4.0 -12.0˚ C) and duration (0 - 72 h), using regression analysis. Based on initial spiking of vegetative …

Shrimp Production Environment And The Gut Microbiome: Effects Of Aquaculture Practices And Selective Breeding On The Gut Microbiome Of Pacific Whiteleg Shrimp, Litopenaeus Vannamei, Angela Landsman

Electronic Theses and Dissertations

Knowledge of the functional role of the gut microbiome in animal health and nutrition may provide solutions to shrimp aquaculture challenges, such as improving disease resistance and optimizing growth particularly with low cost feeds. Successful manipulation of bacteria found in the gut requires a deeper understanding of shrimp microbial communities and how their compositional structure is influenced by environmental conditions, and inherent host factors such as genetics. The initial research investigated the intestinal bacterial communities of the Pacific whiteleg shrimp (Litopenaeus vannamei) reared in pond systems compared to indoor aquaculture facilities as an exploration of the effects of aquaculture practices …

Novel Hybrid Analogs Of Estrone Origin Exhibits Cytotoxic Effects Against Egfr-Dependent Cancers, Felix Acheampong

Electronic Theses and Dissertations

Cancer is second only to cardiovascular illnesses as the deadliest human disease globally. Currently, non-small cell lung cancer (NSCLC) and triple negative breast carcinoma (TNBC) are the most frequent types of cancer and have the highest mortalities. Epidermal growth factor receptor (EGFR), a central regulator of tumor progression, is frequently overexpressed in both cancers and is a key clinical target for therapeutic intervention. Natural products and their synthetic analogs have been utilized as EGFR tyrosine kinase inhibitors (TKIs) with potent antitumor effects. However, acquired resistance limits the long-term efficacy of these drugs. Estrone has been used as a scaffold in …

Effects Of Resistant Starch Type 4 On Gut Microbiota Derived Medium And Long Chain Fatty Acids And Bile Acids, Elizabeth Nagel

Electronic Theses and Dissertations

The human gastrointestinal tract is populated by a diverse and mutualistic microbial flora that has profound effect on human health. Identification and characterization of microbial-metabolites produced in response to human dietary intakes may provide insights into host-microbiota interactions to better understand the role of the microbiota in human health and diseases. However, much of this interaction is poorly understood as many metabolites remain unidentified or understudied at the present time. Starch is ubiquitously present in human diet and is a major energy source to all living cells. Resistant starch (RS) is the starch portion that is not absorbed in the …

Development And Characterization Of Wheat-Thinopyrum Junceiforme Chromosome Addition Lines, Dilkaran Singh

Electronic Theses and Dissertations

Production of wheat is challenged by dynamic biotic and abiotic stresses. Genetic improvement via alien gene transfer is an effective approach to tackle such challenges. Alien gene transfer played an important role in the history of wheat crop improvement. Sea wheatgrass (SWG; Thinopyrum junceiforme, 2n = 28, genomes J1J1J2J2) is a wild relative of wheat. In our previous work, we have developed a complete amphiploid between cultivated emmer and SWG and shown that SWG is resistant to wheat streak mosaic virus, Fusarium head blight and wheat stem sawflies (due to the solid stem) and tolerant to waterlogging, salinity, heat, and …

Isolation And Identification Of Potential Bioinoculants Based On Phosphate Solubilizing And Plant Growth Promoting Benefits, Rachel Raths

Electronic Theses and Dissertations

Conservative models have shown that as populations rise, food production needs to double by 2050. Population increase and the green revolution have caused fertilizer inputs to increase since the 1960’s, increasing environmental issues and production costs. These intensive practices have led to degraded arable land and there has been an increase in urbanization meaning we need to make best use of the farming land that is available and ensure it is sustainable for future food production. Due to this, there has been a higher demand for research on more environmentally and economically friendly approaches to food production. Plant growth promoting …