Life Sciences Commons^™

Multifunctional Regulatory T Cells From Human Umbilical Cord Blood And The Role Of Tumor Necrosis Factor In Immune Homeostasis, Alexander Nelson

Master's Theses

Regulatory T cells (Tregs) are required to suppress inflammation and prevent autoimmunity. During fetal development Tregs are crucial to maintain tolerance between mother and child. After birth, neonates require tolerance to avoid harmful immune responses to foreign antigens in food and allow colonization with commensal microbes. We demonstrate a propensity for T cells in human umbilical cord blood to differentiate into Tregs in response to antigen receptor stimulation ex vivo. Cord blood-derived Tregs potently suppress T cell proliferation, but also produce pro-inflammatory cytokines known to activate innate immune responses. These results suggest that antigen exposure during early life results in …

Dexamethasone Treatment Effects On H3k27me3 Chromatin Organization Is Related To Nk Cell Immune Dysregulation, Michael Sarafeno Misale

Master's Theses

It is well-established that psychological stress reduces natural killer (NK) cell immune function. This reduction is mediated by stress-induced release of glucocorticoids (GC), which can suppress immune function. Associated with suppression of a particular immune function are GC induced histone-epigenetic marks. Histone-epigenetic marks are responsible for the organization and compartmentalization of genomes into transcriptionally active euchromatin domains that are localized to the interior of the nucleus. Transcriptionally silent heterochromatic domains are enriched with methylated epigenetic marks and are localized to the nuclear periphery. The purpose of this investigation was to assess the influence of GC on H3K27me3 chromatin organization by …

Nutrient Removal And Vegetation Recovery Through Successive Harvesting Of The Invasive Hybrid Cattail (Typha X Glauca) In Great Lakes Coastal Wetlands, Kelsey Berke

Master's Theses

Excess nutrient levels have led to invasive hybrid cattail (Typha × glauca) dominance in many Laurentian Great Lakes coastal wetlands. Its ability to alter wetland structure and function has made T. × glauca a target invasive species with respect to Great Lakes coastal wetland

restoration. This study investigated the effect of harvesting invasive T. × glauca biomass on nutrient removal, specifically nitrogen and phosphorus, and plant diversity recovery in Great Lakes coastal wetland ecosystems. This study demonstrated that without considering external nutrient inputs and outputs, a single harvest at Cheboygan Marsh, MI could remove ~2% of the total N and …

Chronic Effects Of Lead Exposure On Atherinops Affinis (Topsmelt): Influence Of Salinity And Organism Age, Erik Joseph Reynolds

Master's Theses

Pb (lead) appears in the environment as a consequence of both natural and anthropogenic processes. Mining, smelting, coal burning, lead acid batteries, and cement manufacturing substantially release Pb into aquatic environments. The goal of this study was to determine the influence of salinity and organism age on chronic toxicity of Pb to Atherinops affinis (topsmelt) in support of development of a species sensitivity distribution (SSD). Species sensitivity distributions assist in ecological risk assessments and establishing quality criteria for contaminants. Three chronic exposure studies were conducted for 28 days in a water flow-through testing system. Survival, standard length, dry weight, and …

Characterization Of Inhibitory Molecules Produced By Lactobacillus Crispatus, Giuseppe Anthony Pistone

Master's Theses

Lactobacillus species are widely accepted as beneficial bacteria of the human microbiota1-8. Lactobacilli spp. are well documented to inhibit pathogens by production and secretion of hydrogen peroxide (H2O2), organic acids, and/or proteinaceous bacteriocins into their environment. Most research attributes bactericidal activity of cell free supernatant (CFS) to H2O2 and/or lactic acid. Here, I demonstrate that CFS from a clinical isolate of Lactobacillus crispatus contains a molecule(s) that inhibits uropathogenic Escherichia coli (UPEC) colony formation independently of H2O2 and organic acids. Physiologic concentrations of H2O2 and organic acids produced by L. crispatus do not inhibit UPEC colony formation. Incubation of UPEC …

Aquatic Insect Community Structure And Secondary Production In Coastal Wetland Ponds Of The Copper River Delta, Alaska: Influence Of Water Temperature And Macrophyte Community Structure, Chantel Caldwell

Master's Theses

The Copper River Delta (CRD), southcentral Alaska, is one of the world’s largest continuous coastal wetlands and is largely composed of sloughs, lakes, and ponds. Due to coastal topography the east side of the Copper River (East Delta) is disproportionately impacted by a cold continental air mass. Wetland communities of the CRD were also impacted by a 9.2 magnitude earthquake in 1964 that shifted the more coastal portion of the CRD from tidally influenced ponds to freshwater ponds.

The West-East temperature gradient across the CRD coupled with landscape type (uplifted marsh (UM) and outwash plain (OP)) creates four regions (West-UM, …

The Role Of Phage Trnas In The Evolution Of Codon Usage Biases In Giant Pseudomonas Phage Phikz And El, Stephanie Steidel

Master's Theses

As the most abundant and diverse biological agents in the biosphere phage have significant roles in microbial ecology, acting both as lethal bacterial parasites and vehicles of horizontal gene transfer. Phage/host coevolution drives optimization of phage codon usage for use of host translational machinery, thus lowered correspondence between phage and host codon usage reduces viral fitness. Some phage may partially bypass host translational selection on their codon usage by encoding their own tRNAs, although the effects of these tRNAs on phage codon usage and translation has not been well examined. This work explores the influence of phage encoded tRNAs on …

West Indian Manatee (Trichechus Manatus) Habitat Characterization Using Side-Scan Sonar, Mindy J. Mclarty

Master's Theses

In this study, the reliability of low cost side-scan sonar to accurately identify soft substrates such as grass and mud was tested. Benthic substrates can be hard to classify from the surface, necessitating an alternative survey approach. A total area of 11.5 km² was surveyed with the sonar in a large, brackish mangrove lagoon system. Individual points were ground-truthed for comparison with the sonar recordings to provide a measure of accuracy. Five substrate types were identified: Dense seagrass, sparse seagrass, mangrove soil, mangrove soil with rock, and silt. A zoned benthic substrate map was created from the sonar recordings. …

Glaucous-Winged Gull Predation On Chicken Eggs Treated With A Uv-Blocking Agent, Athena T. Smith

Master's Theses

Egg cannibalism plays a major role in the life histories of Glaucous-winged Gulls (Larus glaucescens) breeding at Protection Island, Washington. Gulls, along with other birds, visualize reflected ultraviolet (UV) light and I wondered if reflected UV light plays a role in determining which eggs are selected for cannibalization. Motivated by studies showing that tree-nesting bird eggs coated with a UV-blocking agent were less subject to predation than control eggs, I tested whether ground-nesting Glaucous-winged Gulls would preferentially predate control chicken eggs over those coated with a UV-blocking agent. Early during five mornings I formed artificial nests at randomly-determined …

Population Genetics And Distribution Of The Oriental Weatherfish, Misgurnus Anguillicaudatus, In Chicago Area Waterways, John Belcik

Master's Theses

Oriental Weatherfish (Misgurnus anguillicaudatus), native to Southeast Asia, are freshwater fish belonging to the family Cobitidae (loaches). They are benthic fish with the ability to breathe atmospheric air, and exhibit an unusual behavior of swimming vertically in the water column in response to changes in barometric pressure. Oriental Weatherfish appear to be successful invaders to North American waterways. Within the last century they have been sighted in freshwater systems throughout the United States, yet the distribution and source of this invasion are largely unknown. This study investigates the distribution patterns, surveying methods, and population genetics of the Oriental Weatherfish within …

Phylogenetics, Biogeography, And Climate Niche Variation Of South Pacific And Hawaiian Psychotria, Elaine Zhang

Master's Theses

Why do some species have broad geographic distributions, while other species are confined to a narrow distribution? Species age, ecological niche, or dispersal traits may help explain why some insular species are abundant and found on many islands, while others are rare and restricted to one island. In this study, I inferred a robust, time-calibrated phylogeny of the Hawaiian Psychotria, using two nuclear and eight chloroplast loci, sampling 67 individuals. I coupled my phylogenetic hypothesis with climatic data, ecological niche modeling, and morphological dispersal characteristics to explain the variation in number of islands occupied by each species. My inferred phylogeny …

Game Theory Analysis Of Intra-District Water Transfers; Case Study Of The Berrenda Mesa Water District, Harry Riordan Ferdon

Master's Theses

California state officials have continued to warn and encourage preparedness for the growing threats of water scarcity. This puts pressure on water suppliers to develop technological and managerial solutions to alleviate the problems associated with scarcity. A recent popular management strategy for distributing water is encouraging water transfers. While there has been analyses on water transfers between large districts and agencies, little analysis has been completed for smaller scale trades, i.e. between individuals in the same water district. This analysis models an agricultural water district, based on the Berrenda Mesa Water District (BMWD). In the model, the growers in the …

The Response Of A Predatory Fish, Ophiodon Elongatus, To A Marine Protected Area: Variation In Diet, Catch Rates, And Size Composition, Eric S. Anderson

Master's Theses

Marine Protected Areas (MPAs) are a management tool used to protect and sustain many ecologically and economically important fish species from overexploitation by recreational and commercial fishing. Lingcod (Ophiodon elongatus) and some of its prey species, such as rockfish (Sebastes spp.), are species that are protected from fishing in some California MPAs. Lingcod is an apex predator that consumes a variety of fish and invertebrate species. In this study, I sought to assess the effect of an MPA on the abundance, size and diet of Lingcod. I hypothesized that Lingcod in a no-take MPA would be more …

Circadian And Circatidal Rhythms Of Protein Abundance In The Intertidal Mussel Mytilus Californianus, Cory Elowe

Master's Theses

The intertidal zone is a dynamic environment that fluctuates with the 12.4-h tidal and 24-h light/dark cycle to predictably alter food availability, temperature, air exposure, wave action, oxygen partial pressure, and osmotic conditions. Intertidal sessile bivalves exhibit behavioral or physiological changes to minimize the persistent challenges of fluctuating environmental conditions, such as adjusting gaping behavior and heart rate. At the cellular level, transcriptomic studies on mussels’ baseline circadian and circatidal rhythms have determined that the circadian rhythm is the dominant transcriptional rhythm. However, as proteins reflect the basic molecular phenotype of an organism and their abundance may differ greatly from …

The Elasmobranch-Microbe Relationship: Trimethylamine N-Oxide Synthesis, Urea Hydrolysis, And Microbe-Osmolyte Interactions In The Atlantic Stingray, Dasyatis Sabina, Kaitlin Kelly Doucette

Master's Theses

The elasmobranch osmoregulatory strategy is predicated on the accumulation of nitrogenous compounds, primarily urea and trimethylamine n¬-oxide (TMAO). Despite the abundance of these plasma osmolytes, it is notable that elasmobranchs appear to lack urease and TMA oxidase (Tmase), enzymes that scavenge urea-nitrogen and synthesize TMAO, respectively. However, urease and Tmase are found in many species of bacteria. Therefore, I hypothesized that intestinal bacteria are responsible for urease and Tmase activity in elasmobranchs. Absent dietary nitrogen sources, I evaluated the effects of reduced intestinal microbiota on osmoregulation in Atlantic stingray (Dasyatis sabina) in vivo. D. sabina were given …

Fecal Bacterial Communities As An Indicator Of Trophic Interactions Among Anuran Larvae, Steven Jacob Everman

Master's Theses

Anurans are mass spawners, often with multiple females spawning together, resulting in thousands of tadpoles sharing a habitat. Such large numbers of tadpoles with limited dispersal can lead to intense competition for resources. Inter and intra-specific competition for food could have negative impacts on the growth and survival of smaller tadpoles. Fecal bacterial communities have the potential to be used as indicators of changes in diet making it possible to determine if tadpoles in the wild are eating the same food or not. After feeding on two prepared diets that differed in the percentage of complex carbohydrates, the fecal bacterial …

Modern Fair-Weather And Storm Sediment Transport Around Ship Island, Mississippi: Implications For Coastal Habitats And Restoration Efforts, Eve Rettew Eisemann

Master's Theses

The Mississippi – Alabama barrier island chain is experiencing accelerated sea level rise, decreased sediment supply, and frequent hurricane impacts. These three factors drive unprecedented rates of morphology change and ecosystem reduction. All islands in the chain have experienced land loss on the order of hectares per year since records began in the 1840s. In 1969, Hurricane Camille impacted as a Category 5, breaching Ship Island, and significantly reduced viable seagrass habitat. Hurricane Katrina impacted as a Category 3 in 2005, further widening Camille Cut. To better understand the sustainability of these important islands and the ecosystems they support, sediment …

Bloom Or Bust: Retrospective Analysis Of The Giant Jellyfish, Nemopilema Nomurai (Scyphozoa: Rhizostomeae), Ecology In The East Asian Marginal Seas, Naomi Yoder

Master's Theses

The Giant Jellyfish, Nemopilema nomurai, is a large-bodied bloom-forming jellyfish that occurs in the semi-enclosed basins of the East Asian Marginal Seas. N. nomurai has bloomed more frequently in the past 20 years than in any period previously recorded. In Japan, recent N. nomurai blooms were responsible for millions of dollars in lost revenue and equipment damage to commercial fisheries alone. This study statistically analyzed 21 environmental factors in connection with N. nomurai occurrence (using occurrence as a proxy for blooms). Eight factors resulted in a statistically significant or marginally significant (p ≤ 0.10), linear or non-linear relationship with …

Effect Of Fragmentation And Habitat Type On Coastal Nekton In Mississippi, Thomas Bennett Sevick

Master's Theses

Coastal wetlands are extremely productive ecosystems that support an abundance of organisms at higher tropic levels. Coastal wetlands also act as important buffers from storms and help protect major cornerstones of coastal economies, such as tourism and fisheries. Despite the clear need for the protection of these habitats, anthropogenic use of coastal wetlands has increased in frequency and intensity, resulting in the fragmentation of once continuous habitats. A central challenge to assessing the impact of marsh fragmentation is the lack of quantitative distribution and abundance data from specific habitat types. This is especially true for species that are not commercially …

Gulf Sturgeon (Acipenser Oxyrinchus Desotoi) Pre-Restoration Occupancy Patterns On Ship Island, Mississippi Sound With An Evaluation Of Designated Critical Habitat Use By Eastern And Western Population Segments, Page Elizabeth Vick

Master's Theses

Critical spawning and feeding habitat was designated for federally threatened, anadromous Gulf Sturgeon (GS) to aid in population recovery. This study examined GS occupancy, habitat use, and movement through critical habitat monitored by the Ship Island (SI) acoustic array during overwintering periods from 2011 to 2015 prior to MsCIP SI restoration. An occupancy index analyzed patterns of spatial and temporal habitat use of both western and eastern population segments (WPS and EPS, respectively) of GS on the SI array. The ends of SI along with the passes and cuts of the island, especially Dog Keys Pass (DKP), were occupied by …

The Importance Of The Multicomponent Display In Sexual Selection Of Black Morph Girardinus Metallicus (Pisces: Poeciliidae), Erin M. Wojan

Master's Theses

Multicomponent displays are composed of traits, such as coloration, structural ornaments, and behavior, that become integrated and signal information to conspecifics. Estimation of multicomponent displays in fishes often involves measurement of color traits. Fish color measurements are often obtained following immobilization via chemical anesthesia; however, the anesthetics may alter the resulting measurements, for example by darkening the skin. Girardinus metallicus, a poeciliid fish endemic to Cuba, has a multicomponent courtship and aggressive display. Black morph males exhibit black ventral coloration including the gonopodium (copulatory organ) and yellow in the non-black areas of their bodies. I investigated the effects of …

Metabolic Regulation And Cryotolerance Of In Vitro-Produced Holstein Embryos, Melissa Ann Roberts

Master's Theses

In vitro production and transfer of embryos has become a common practice within the dairy industry to efficiently breed superior animals and meet the consumption demand of the growing population. Cyropreservation is necessary for the application of commercialized embryo transfer, however, in vitro-produced embryos show morphological and physiological defects which negatively impact their ability to withstand cryopreservation in comparison to their in vivo counterparts. These artifacts result from culture conditions that cause stress to the embryo during development, leading to an accumulation of intracellular lipids, mitochondrial dysfunction, and ultimately poor ability to withstand freezing and thawing. The objective of …

Effect Of Oxygen-Limiting Tidal Conditions On Muscle Metabolism And Structure In The Giant Acorn Barnacle, Balanus Nubilus, Katie O. Grady

Master's Theses

Crustacean muscle fibers are some of the largest cells in the animal kingdom, with fiber diameters in the giant acorn barnacle (Balanus nubilus) exceeding 3 mm. Sessile animals with extreme muscle sizes and that live in the hypoxia-inducing intertidal zone – like B. nubilus – represent ideal models for probing the effects of oxygen limitation on muscle cells. We investigated changes in metabolism and structure of B. nubilus muscle in response to: normoxic immersion, anoxic immersion, or air emersion, for acute (6h) or chronic (6h exposures twice daily for 2wks) time periods. Following exposure, we immediately measured hemolymph …

Eye Tracking Food Cues In Subjects Who Are Overweight/Obese, Weight Loss Maintainers, And Normal Weight, Carrie A. Petro

Master's Theses

Adult obesity is associated with increased morbidity and mortality. Increasing success in weight loss maintenance will decrease the prevalence of overweight and obesity, and therefore help control the adverse health effects of excess weight. Much is known about the behavioral characteristics of successful long-term weight loss maintenance, but less is known about the cognitive processes behind weight loss maintenance. The purposes of this study were to (1) identify differences in visual attention to high-energy dense foods between individuals who are normal weight, weight loss maintainers, and overweight/obese in a high-risk (food-buffet) situation; (2) to evaluate differences in food choices from …

Physically Effective Fiber Threshold, Apparent Digestibility, And Novel Fecal Microbiome Identification Of The Leopard Tortoise (Stigmochelys Pardalis), Breanna Paige Modica

Master's Theses

Particle size distribution of diet, feces, and change from diet to feces, as well as apparent digestibility (aDig, %) of selected nutrients, and novel fecal microbiome identification of mature female leopard tortoises (Stigmochelys pardalis, n = 16) fed exclusively one of three, nutritionally complete, pelleted diets were evaluated in a blind, complete randomized design study. Two diets included insoluble fiber (powdered cellulose) consisting of either 2.0 mm or 0.2 mm length. Insoluble fiber provides nutritional and physical benefits to both the animal host and the microorganisms that inhabit the gastrointestinal tract. Insoluble fiber length was used as a …

Community Structure And Production Of The Macrobenthos On Four Artificial Reefs In The Mississippi Sound In Relation To Substrate And Profile Type, Patrick Daniel Gillam

Master's Theses

In recent years, the Mississippi Department of Marine Resources (DMR) has made a concerted effort to enhance its coastal fishery resources by creating artificial reefs. Through this effort, 73 nearshore reefs have been created across the MS coast. Different substrate types used to construct MS artificial reefs include oyster shell and cement rubble. Two types of reef architecture used include high profile breakwater and low profile submerged structures. This study compared the benthic biota associated with oyster shell and cement rubble substrates among four artificial reefs representing high and low profile structures in summer 2011. Colonized benthic biota were quantified …

Reconstitution Of Munc18-Dependent Mast Cell Degranulation, Matthew Grant Arnold

Master's Theses

Mast cells are specialized secretory leukocytes that play diverse roles in the body, mediated by release of histamine and other pharmacologically active substances. Although offering essential protection in innate and adaptive immunity, mast cells are also essential to the progression of inflammatory diseases, including allergy and asthma, (Theoharides et al., 2012). Exocytosis of pro-inflammatory mast cell mediators in response to otherwise innocuous antigens relies on evolutionarily-conserved membrane fusion machinery. These proteins, called SNAREs are regulated by the Sec1/Munc18 (SM) protein family (Axle Lorentz, Baumann, Vitte, & Blank, 2012). Mast cells express three mammalian Munc18 isoforms (a, b, and c), which …

Effects Of Fire On Soil Co₂ Efflux In A Mature Longleaf Pine Forest, Knox Lemee Flowers

Master's Theses

This study was conducted from 2012-2013 in a 96 year old longleaf pine at the Lake Thoreau Environmental Center located Lamar County, MS. Measurements of soil CO₂ efflux (i.e., soil respiration or SR) rates (µmol m^-2 sec^-1) were taken across 8 field plots (4 burned, 4 unburned) before and after a prescribed fire on that occurred in May, 2012. These measurements were taken over diurnal cycles using a LICOR LI-8100A automated soil gas flux system with long term chambers. SR rates and soil temperature measurements were collected during 3 sampling periods in 2012 and 1 sampling period …

Growth And Reproduction Of Southern Flounder (Paralichthys Lethostigma) In The North-Central Gulf Of Mexico, Morgan Marie Corey

Master's Theses

Southern Flounder Paralichthys lethostigma is the most commonly harvested flatfish in the north-central Gulf of Mexico (GOM) and supports a major inshore recreational fishery, yet knowledge of the species’ life history is greatly limited. The objective of this research was to describe the growth and reproduction of Southern Flounder in the Mississippi stock. Fish were collected during September 2014 to March 2016 using primarily recreational fishing techniques. Otoliths (n = 313) were sectioned to estimate age, and multiple length-at-age models were fit to total length (TL, mm) and age estimate (y) data. Gonadal tissue samples (n = 221) …

Development Of Genomic Resources For The Evaluation Of Red Snapper, An Emerging Species Candidate For Marine Aquaculture And Stock Enhancement, Adrienne Elise Norrell

Master's Theses

The northern red snapper (Lutjanus campechanus) is a highly targeted reef fish candidate for marine aquaculture and stock enhancement in the southern United States. This work aimed to develop genomic resources for the genetic management of aquaculture programs and to investigate population structure using high-throughput sequencing technologies. Eighty-four new microsatellite markers were developed through screening of Illumina paired-end sequencing reads. Microsatellite loci and Single Nucleotide Polymorphisms (SNPs) generated through Restriction Site Associated DNA (RAD) sequencing were assayed in 5 outbred full-sib families to construct a high-density linkage map of the red snapper genome. The map consists of 7,964 …