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Full-Text Articles in Life Sciences

An Investigation Into Structural Plasticity In Peripheral Taste Neurons Associated With Taste Cell Turnover., Zachary Whiddon May 2023

An Investigation Into Structural Plasticity In Peripheral Taste Neurons Associated With Taste Cell Turnover., Zachary Whiddon

Electronic Theses and Dissertations

The continual replacement of taste cells creates interesting questions regarding how the innervating neurons are impacted during this process. Here we ask how innervation within taste buds is affected when taste cell entry is inhibited and reestablished. Inhibition of sonic hedgehog signaling (Shh) is thought to inhibit taste cell turnover. Consistently, fewer new cells were added to individual taste buds after treatment with a Shh-inhibitor compared to vehicle treatment, and taste bud volume decreased after 16 days of treatment. We next examined how taste nerve fiber extension into the gustatory epithelium is affected by preventing taste cell turnover. Ten days …


Identification Of A Role Beyond Iron Acquisition For Yersiniabactin During Yersinia Pestis Infection., Sarah Price May 2023

Identification Of A Role Beyond Iron Acquisition For Yersiniabactin During Yersinia Pestis Infection., Sarah Price

Electronic Theses and Dissertations

Yersinia pestis is a Gram-negative re-emerging bacterial pathogen that is responsible for bubonic, septicemic, and pneumonic plague. Y. pestis and other bacteria require transition metals, such as iron, zinc, and manganese, to maintain intermediary metabolism, transcriptional regulation, and virulence. To inhibit infection, eukaryotic organisms have developed distinct mechanisms, called nutritional immunity, to sequester these important nutrients from invading bacteria. For pathogens to colonize the vertebrate host, they have evolved dedicated acquisition systems for transition metals. During infection, Y. pestis overcomes iron limitation by secreting the siderophore yersiniabactin. Additionally, Y. pestis requires zinc for infection and utilizes high affinity transporters to …


Transmission And The Evolution Of Diseases Caused By Chlamydia Trachomatis, Sars-Cov-2, And Plasmodium Species., Nathan Steffens May 2023

Transmission And The Evolution Of Diseases Caused By Chlamydia Trachomatis, Sars-Cov-2, And Plasmodium Species., Nathan Steffens

Electronic Theses and Dissertations

Principles of natural selection have proven valuable for explaining why pathogens cause the diseases that they do. In theory, the evolved level of host exploitation should reflect how dependent a pathogen is on host health for transmission. This dependency is shaped by transmission mode and transmission opportunity, which should therefore be predictors of disease manifestations. In this dissertation, I apply these principles to investigations of depression in Chlamydia trachomatis and virulence of SARS-COV-2 and Plasmodium species. This dissertation has five chapters. In chapter I, I describe the theoretical foundation of my dissertation research. I also briefly introduce each study system. …


Small Gtpase Regulated Intracellular Protein Trafficking In Endothelium, Caitlin Francis Mar 2023

Small Gtpase Regulated Intracellular Protein Trafficking In Endothelium, Caitlin Francis

Electronic Theses and Dissertations

Intracellular protein trafficking is the movement of membrane-bound organelles to and from requisite locations within the cell. Small GTPases are a critical component to the spatiotemporal accuracy of intracellular trafficking pathways as they determine the specificity and direction of organelle transport. There exists over 150 small GTPases categorized into 5 sub-families and are employed across all cell types. Despite their universal expression and relevance to cellular function, small GTPases remain incompletely understood across tissue types. In various instances, the trafficking pathway of a particular Rab in one cell type may belong to a completely disparate pathway in another cell type. …


Uncovering Zn2+ And Ca2+ Homeostasis And Crosstalk In Primary Hippocampal Neurons, Chen Zhang Mar 2023

Uncovering Zn2+ And Ca2+ Homeostasis And Crosstalk In Primary Hippocampal Neurons, Chen Zhang

Electronic Theses and Dissertations

Zn2+ has been suggested to act as an intracellular signaling molecule due to its regulatory effects on numerous protein targets including enzymes, transcription factors, ion channels, neurotrophic factors, and postsynaptic scaffolding proteins. However, intracellular Zn2+ concentration is tightly maintained at steady levels under natural physiological conditions. Dynamic changes in intracellular Zn2+ concentration have only been detected in cells exposed to pathologic stimuli or upon receptor ligand binding. In the first project of my dissertation, for the first time, we revealed that developing neurons fire spontaneous and synchronous Zn2+ spikes at a specific time window (from 14 …


A Comparison Of Microsatellites And Single Nucleotide Polymorphisms For The Assessment Of Population Structure In The Amblyomma Maculatum Koch, 1844 Species Complex, Henrey A. Deese Jan 2023

A Comparison Of Microsatellites And Single Nucleotide Polymorphisms For The Assessment Of Population Structure In The Amblyomma Maculatum Koch, 1844 Species Complex, Henrey A. Deese

Electronic Theses and Dissertations

The Gulf Coast tick, Amblyomma maculatum Koch, 1844 is widespread throughout North and Central America and is the primary vector for the emerging pathogen Rickettsia parkeri. In the U.S., the population in the Southwest (A. maculatum morphotype III) is morphologically different from the population east of the Rocky Mountains (A. maculatum morphotype II). This research tests the hypothesis that A. maculatum morphotype II and morphotype III represent distinct species through the analysis and comparison of 6 microsatellite loci and suite of 135,221 Single nucleotide polymorphisms (SNPs) generated from ddRADseq. Population genetic analysis of both microsatellites and SNPs …


Neural And Behavioral Evolution In An Eavesdropper With A Rapidly Evolving Host, Aaron W. Wikle Jan 2023

Neural And Behavioral Evolution In An Eavesdropper With A Rapidly Evolving Host, Aaron W. Wikle

Electronic Theses and Dissertations

The diversification of animal communication systems is driven by many interacting factors. Unintended receivers play an important part in this process, yet little is known about their role in signal evolution. Flies of the genus Ormia are parasitoids of crickets and rely on acoustic cues to locate hosts. In Hawaii, selection imposed by Ormia ochracea has led to recent and rapid diversification in the songs of their host. Here, we compare neural and behavioral responses of Hawaiian flies to those of an ancestral population to understand the role of parasitoid sensory and behavioral variation in the evolution of host songs. …


Surviving The Serenade: How Conflicting Natural And Sexual Selection Drove Rapid Diversification Of Mating Signals In An Insect, James H. Gallagher Jan 2023

Surviving The Serenade: How Conflicting Natural And Sexual Selection Drove Rapid Diversification Of Mating Signals In An Insect, James H. Gallagher

Electronic Theses and Dissertations

Understanding how the early stages of sexual signal diversification proceed is of critical importance because the nature of these microevolutionary dynamics can directly shape species trajectories and macroevolutionary patterns. Unfortunately, studying signal diversification is challenging because signals involve complex interactions between behavioral, morphological, and physiological components, many of which can only be measured in real time. Here we had the opportunity to directly study this process with the recent increase in sexual signal variation in Hawaiian populations of the Pacific field cricket (Teleogryllus oceanicus). In Hawaii, male song attracts both female crickets and a deadly acoustically orienting parasitoid …


Quantification Of Nuclear Dynamics During Epithelial Remodeling, Noah De Leeuw Jan 2023

Quantification Of Nuclear Dynamics During Epithelial Remodeling, Noah De Leeuw

Electronic Theses and Dissertations

The morphogenesis of developing tissues is contingent on an extensive array of rearrangements in cellular shape, position and identity at large and small scales. One commonly used process to reshape tissues is the cell intercalation-driven elongation of a tissue in a common axis, in which rows of epithelial cells undergo oriented intercalation in a directional fashion. In most models of intercalation, cells are treated as homogeneous objects directed in their shape changes by cortical forces localized along cell-cell interfaces or tricellular junctions. However, less attention has been paid to how inhomogeneities in mechanical resistance of their own internal structures affects …


Mechanistic Insights Into Mftr-Dependent Regulation Of The Redox Cofactor Mycofactocin, Aigera Mendauletova Jan 2023

Mechanistic Insights Into Mftr-Dependent Regulation Of The Redox Cofactor Mycofactocin, Aigera Mendauletova

Electronic Theses and Dissertations

Organic redox cofactors are essential for life. While classic flavins and nicotinamides are widely distributed across all domains of life, nature has also evolved niche cofactors in subsets of life domains. For example, in Actinobacteria, coenzyme F420 is commonly used in place of flavin mononucleotide in enzymes associated with carbon fixation and oxidation of secondary alcohols. The importance of niche cofactors has long been recognized however, detailed understanding about their biosynthesis and physiological uses has been lagging. One class of niche cofactors is derived from ribosomally synthesized and posttranslationally modified peptides (RiPPs). To achieve their mature form, the genetically …


Plant Community Response To Control Of A Dominant Invader At Multiple Scales, Alexander R. B. Goetz Jan 2023

Plant Community Response To Control Of A Dominant Invader At Multiple Scales, Alexander R. B. Goetz

Electronic Theses and Dissertations

Control of invasive Tamarix spp. in riparian systems has long been a priority for management in western North America, but questions remain regarding the response of the broader plant community to different treatments. Here we summarize a series of approaches at different scales to quantify the effects of Tamarix control on characteristics of this ecosystem, including provisioning of wildlife habitat. In the first chapter we analyzed findings of the last 20 years using meta-analysis and found that although treatment has been successful in reducing Tamarix and promoting native vegetation to some extent, most literature reports very small effect sizes and …


Developing Red Fluorescent Zn2+ Sensors And Characterizing Zn2+ Homeostasis In Mucolipidosis Type Iv Disease, Anna M. Dischler Jan 2023

Developing Red Fluorescent Zn2+ Sensors And Characterizing Zn2+ Homeostasis In Mucolipidosis Type Iv Disease, Anna M. Dischler

Electronic Theses and Dissertations

Zinc (Zn2+) is a divalent, redox-inert metal that plays a vital role in many cellular processes either by acting as a catalytic cofactor or a labile signaling molecule in the cytoplasm. Cytosolic Zn2+ levels are tightly regulated to stay within a narrow window of concentrations, but fluctuations in Zn2+ signals have been detected in a variety of cells. We developed a genetically encoded, single red fluorescent protein (RFP) based Zn2+ sensor, RZnP1, that can be used alongside green-wavelength sensors for the simultaneous detection of different signaling molecules within the same cells or among different subcellular …


The Evolutionary Causes And Consequences Of Mammalian Hybridization, Kelsie E. Hunnicutt Jan 2023

The Evolutionary Causes And Consequences Of Mammalian Hybridization, Kelsie E. Hunnicutt

Electronic Theses and Dissertations

The natural recombination of divergent genomes within hybrid offspring provides windows through which we can study evolutionary processes and the dynamics of speciation. In this work, I use a combination of comparative and population genomics on both laboratory crosses of divergent rodent lineages and a hybrid zone of cottontail rabbits in the wild to study the causes and consequences of hybridization in mammals. Hybrid sterility is a common reproductive barrier between species that tends to preferentially manifest in the heterogametic sex and frequently genetically maps to the sex chromosomes. Thus, the sex chromosomes appear to play a special role in …


Post-Translational Modification Of Proteins Via Ambient Air Pollutants And Endogenous Reactive Species, Rachel Lauren Davey Jan 2023

Post-Translational Modification Of Proteins Via Ambient Air Pollutants And Endogenous Reactive Species, Rachel Lauren Davey

Electronic Theses and Dissertations

Proteins can react with reactive oxygen species (ROS) and reactive nitrogen species (RNS) to form post-translational modifications (PTMs), which can affect protein structure and function. The formation of 3-nitrotyrosine (NTyr) and dityrosine (DiTyr) upon reaction of proteins with ROS/RNS are two common PTMs studied due to their stability and irreversibility, as well as their ability to enhance the allergenicity of pollen allergens upon formation. Many common techniques used to study the formation of these PTMs can reliably detect the PTMs but can only provide semi-quantitative information due to many assumptions and limitations. In Chapter 2 we present an analysis of …


Identifying The Role Of Phospholipase D1 And Phosphatidic Acid In Exocytosis, Broderick L. Bills Jan 2023

Identifying The Role Of Phospholipase D1 And Phosphatidic Acid In Exocytosis, Broderick L. Bills

Electronic Theses and Dissertations

Exocytosis is an essential process for intercellular communication in eukaryotic cells. This process involves significant changes in membrane curvature, and lipids and curvature-sensing proteins can assist these processes. One protein in particular, phospholipase D1 (PLD1), and its product, the lipid phosphatidic acid (PA), are involved in multiple exocytic processes. However, PLD1 and PA’s role in this process has remained unclear. In this work, PLD1 and the production of PA were visualized during exocytosis, and PA localization to regions of membrane curvature was established. Together, these results support the hypothesis that PLD1 production of PA stabilizes negative curvature during membrane fusion. …


Novel Delivery Systems Of Curcumin And Resveratrol, Mohamed Salem Elfaruk Jan 2023

Novel Delivery Systems Of Curcumin And Resveratrol, Mohamed Salem Elfaruk

Electronic Theses and Dissertations

No abstract provided.


Development Of Probiotic Whipped Cream And Butter Using Whey Protein Hydrolysate-Encapsulated Probiotic Organisms, Kritika Gaba Jan 2023

Development Of Probiotic Whipped Cream And Butter Using Whey Protein Hydrolysate-Encapsulated Probiotic Organisms, Kritika Gaba

Electronic Theses and Dissertations

No abstract provided.


The Impact Of Increasing Dietary Levels Of Hybrid Rye On Growing-Finishing Pig Performance, Carcass Characteristics, And Meat Quality, Caitlyn Sullivan Jan 2023

The Impact Of Increasing Dietary Levels Of Hybrid Rye On Growing-Finishing Pig Performance, Carcass Characteristics, And Meat Quality, Caitlyn Sullivan

Electronic Theses and Dissertations

The objective of this trial was to determine the effects of increasing dietary levels of hybrid rye on growth performance, carcass characteristics, and product quality of growing-finishing pigs. A total of 2,400 barrows and gilts (FAST x PIC 800, initial wt. 44.9 kg) were utilized, as pigs were randomly assigned to one of the four dietary treatments. Diets were corn-soybean based and hybrid rye replaced corn at 0, 40, 70, or 100%. All diets were formulated to meet or exceed the 2012 NRC requirements for all nutrients and fed through a five-phase feeding program (44.9 to 125 kg, respectively). Pigs …


Identifying Optimum Germination Temperatures And Analysis Weights In Seed Testing For Stiff Goldenrod (Solidago Rigida) And River Bulrush (Bolboschoenus Fluviatilis), Rachel Geary Jan 2023

Identifying Optimum Germination Temperatures And Analysis Weights In Seed Testing For Stiff Goldenrod (Solidago Rigida) And River Bulrush (Bolboschoenus Fluviatilis), Rachel Geary

Electronic Theses and Dissertations

Federal and state seed laws require seed lots offered for sale to be tested and labeled with the appropriate information before they can be sold. Those tests are conducted in seed testing labs all around the world. In the United States, accredited seed testing labs follow the Association of Official Seed Analysts (AOSA) Rules for Testing Seeds to provide information for labeling. The rules lack instructions for weights and germination for many native species. Stiff goldenrod (Solidago rigida) and river bulrush (Bolboschoenus fluviatilis) are two species that lack any information required for testing. When seed testing labs use correct weights …


Feeding Strategies To Improve Gastrointestinal Health And Growth Performance Of Confinement Fed Ruminants, Forest Laine Francis Jan 2023

Feeding Strategies To Improve Gastrointestinal Health And Growth Performance Of Confinement Fed Ruminants, Forest Laine Francis

Electronic Theses and Dissertations

The objective of this dissertation was to investigate how feed additives, orally administered direct fed microbials, and dietary management strategies may be beneficial in improving gastrointestinal health and growth performance of confinement fed ruminants. Four studies were conducted using confinement fed steers (n = 3) and wether lambs (n = 1) to determine the effects of the products and management strategies used. The first study was conducted on finishing steers to investigate the effects of increasing doses of an encapsulated butyric acid and zinc supplement (BZ) on growth performance, efficiency of dietary net energy utilization, carcass characteristics, and gastrointestinal health. …


Genome-Wide Association Studies And Advanced Genomic Selection Strategies: Towards The Optimization Of Oat (Avena Sativa L) Breeding, Girma Ayana Jan 2023

Genome-Wide Association Studies And Advanced Genomic Selection Strategies: Towards The Optimization Of Oat (Avena Sativa L) Breeding, Girma Ayana

Electronic Theses and Dissertations

Oats are important cereal crops worldwide, primarily valued for their nutritional and health benefits. The primary goal of oat breeding programs is to accelerate genetic gain to develop oat varieties with the desired product profiles, with the aim of meeting the needs and expectations of growers, processors, and consumers. Achieving this goal involves conducting extensive and resource-intensive field trials, particularly for traits such as crop yield and grain quality, which are strongly influenced by environmental factors. The availability of cost-effective molecular markers and tools like genome-wide association studies (GWAS) and genomic selection have the potential to accelerate the oat breeding …


Characterization Of Parp1-Dependent Poly-Adp-Ribosylation Of Sprtn, Quincee Simonson Jan 2023

Characterization Of Parp1-Dependent Poly-Adp-Ribosylation Of Sprtn, Quincee Simonson

Electronic Theses and Dissertations

DNA-protein crosslinks (DPCs) are a type of DNA lesion that form when proteins become covalently linked to DNA. It is estimated that replicating cells experience approximately 6,000 DPCs per day per genome during exponential growth (Ruggiano & Ramadan, 2021). If left unrepaired, DPCs can be lethal to cells. For this reason, cells have evolved multiple pathways to repair or bypass DPCs to survive. One such pathway involves SPRTN, a nuclear metalloprotease that plays a key role in the repair of DPCs through direct proteolysis (Lopez-Mosqueda et al., 2016; Vaz et al., 2016). Once SPRTN degrades the bulky protein component of …


Seroprevalence Of Sars-Cov-2 Antibodies Among Rural Healthcare Workers, Jordan Neises Jan 2023

Seroprevalence Of Sars-Cov-2 Antibodies Among Rural Healthcare Workers, Jordan Neises

Electronic Theses and Dissertations

The objective of this longitudinal cohort study was to determine the seroprevalence of antibodies to severe acute respiratory syndrome coronavirus-2 (SARSCoV- 2) in healthcare workers employed at healthcare clinics in three rural counties in eastern South Dakota and western Minnesota from May 13, 2020 through December 22, 2020. Three blood draws were performed at five clinical sites and tested for the presence of antibodies against the SARS-CoV-2 virus. Serum samples were tested for the presence of antibodies using a fluorescent microsphere immunoassay (FMIA), neutralization of SARS-CoV-2 Spike-pseudotyped particles (SARS-CoV-2pp) assay, and serum virus neutralization (SVN) assay. The seroprevalence was determined …


Extraction, Characterization, And Utilization Of Yellow Pea Starch, Abdulmalik Albu Tuwaybah Jan 2023

Extraction, Characterization, And Utilization Of Yellow Pea Starch, Abdulmalik Albu Tuwaybah

Electronic Theses and Dissertations

Dry peas, a leguminous crop, are one of the world's oldest crops, accounting for 35–40% of total pulse trade. Pea starch is an inexpensive source of starch since it can be obtained as a by-product of protein extraction. Recovering the starch from protein isolation streams (i.e., before or after) improves the environmental impact of the protein isolation process. The goal of the study was to transform low-value pea starch into highvalue starch through starch extraction and food application. Two methods of starch extraction were used (47.5% ethanol treatment and SC CO2 + EtOH extraction). Starch samples were analyzed for chemical, …


Building No-Tillage Maize Nitrogen Recommendation Algorithm That Considers Improvements In Soil Health, Dwarika Bhattarai Jan 2023

Building No-Tillage Maize Nitrogen Recommendation Algorithm That Considers Improvements In Soil Health, Dwarika Bhattarai

Electronic Theses and Dissertations

In long-term no-till fields, farmers have reported that less N is required to optimize maize (Zea mays L.) yields in long term no-tillage fields than conventional tillage fields. These reductions may be attributed to improved soil health resulting from increasing soil organic matter, higher soil microbial activities, and improved water and nutrient use efficiency. However, the impact of soil health measurements on fertilizer-N requirement has not been determined. The objective of this dissertation was to compare different regional N recommendation models to measured values and develop a maize fertilizer-N recommendation model, using machine learning approaches, that includes adjustments based on …


Impact Of Virtual Fence Technology On Yearling Steer Behavior, Performance, And Energetic Expenditure, Logan Riley Vandermark Jan 2023

Impact Of Virtual Fence Technology On Yearling Steer Behavior, Performance, And Energetic Expenditure, Logan Riley Vandermark

Electronic Theses and Dissertations

Beef cattle production in the U.S. is largely dependent upon extensive rangelands like the Northern Great Plains. Solutions are needed to meet both the demand of animal-based protein products for a growing world population and the desire for producers to manage for several different ecosystem functions. Virtual fencing (VF) is an emerging precision technology that has the potential to revolutionize livestock management on extensive rangeland systems. However, the need to quantify animal behavior and performance differences using emerging precision technologies, like VenceTM, is ever growing. Thus, the objective of this research was to determine the impact of virtual fencing on …


Modulatory Effects Of Deacetylated Sialic Acids (A Sugar Residue) In Nk-Mediated Cytotoxicity And Targeted Therapy By Receptor Tyrosine Kinase Inhibitors, Mathias Tawiah Anim Jan 2023

Modulatory Effects Of Deacetylated Sialic Acids (A Sugar Residue) In Nk-Mediated Cytotoxicity And Targeted Therapy By Receptor Tyrosine Kinase Inhibitors, Mathias Tawiah Anim

Electronic Theses and Dissertations

The complex nature of the biology of cancer is still an unraveling science, yielding several biomarkers that have served as molecular targets for detection and treatment of the disease. How sugars, glycans, play a role has remained relatively uninvestigated. Sialic acid (Sia), a sugar residue on the surface of cells, has been identified as a hallmark of cancer and its progression. Sialic acid can be highly functionalized, but we became interested in acetylated Sias. This functional group is modulated by Sialate O- acetylesterase (encoded by the gene SIAE) and Sialate O-acetyltransferase (encoded by CASD1), enzymes that play a crucial role …


Relating Predator Community Ecology And Duck Nest Survival In Eastern South Dakota, Samantha R. Fino Jan 2023

Relating Predator Community Ecology And Duck Nest Survival In Eastern South Dakota, Samantha R. Fino

Electronic Theses and Dissertations

As conversion of native grasslands and wetlands to croplands continues in the Prairie Pothole Region (PPR), managers are tasked with maintaining sustainable waterfowl populations. Mesopredator community dynamics is a hypothesized mechanism driving spatiotemporal variation of waterfowl nest survival in the PPR, yet studies often lack detailed information on mesopredator species occurrence and abundance. Therefore, understanding spatial and temporal variation in behaviors of mesopredators provides valuable insights for understanding predator-prey interactions between mesopredators and upland duck nests. Further, differences in a predator community resulting from lethal removal of dominant species may influence composition and space use patterns of subordinate and non-target …


Aphid Parasitoid Wasps (Insecta: Hymenoptera: Braconidae, Aphidiinae) Of The Americas: Species Discovery, Key To Genera, Annotated Checklist, And Summary Of Biology, Abigail Paige Martens Jan 2023

Aphid Parasitoid Wasps (Insecta: Hymenoptera: Braconidae, Aphidiinae) Of The Americas: Species Discovery, Key To Genera, Annotated Checklist, And Summary Of Biology, Abigail Paige Martens

Electronic Theses and Dissertations

No abstract provided.


Tracking Nitrogen Mineralization In The Presence Of Biochar Utilizing Complementary-Method Assays In East Central South Dakota, Andrew Calvin Engel Jan 2023

Tracking Nitrogen Mineralization In The Presence Of Biochar Utilizing Complementary-Method Assays In East Central South Dakota, Andrew Calvin Engel

Electronic Theses and Dissertations

Understanding soil N transformations in agricultural systems of the Northern Great Plains is crucial for guiding effective soil and nutrient management of this vital cropland. While the use of biochar in agriculture has attracted great attention recently, little has been reported on the seasonal dynamics of soil nitrogen (N) transformation and its response to biochar application. A field experiment was conducted over 2 seasons, spring (6/3/19-6/24/19) and summer (7/26/19-8/16/19), using four treatments or control soil, urea (224 kg N/ha), biochar (46,250 kg/ha), and urea+biochar (224 kg N/ha and 46,250 kg/ha, respectively). The results for both seasons showed biochar had no …