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The Regulation Of Epithelial Sodium Channels In Mammalian Taste Receptor Cells, Arian F. Baquero Gonzalez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nutrient recognition is one of the main physiological roles of the gustatory system. In mammals, it is well established that the taste of sodium salts is primarily mediated by sodium influx through the epithelial sodium channel. The epithelial sodium channel is a sodium-specific ion channel that is expressed across a wide range of transporting epithelia such as colon, kidney, and taste. In addition to its role as a salt taste receptor, sodium influx through the epithelial sodium channel is important systemically for maintaining sodium balance and blood pressure. Following our earlier work on the endocrine regulation of salt taste at …

Targeting Fat-Sensitive Pathways In Enteroendocrine Cells Using Nanoparticle-Mediated Drug Delivery, Bhavik P. Shah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The current epidemic of obesity has been linked to an increase in fat intake associated with the Western diet. Nutrient-induced stimulation of enteroendocrine cells in the small intestine leads to the release of hormones that contribute to satiety and the control of food intake. In particular, ingested fat, specifically in the form of free fatty acids, is potent activator of enteroendocrine cells in the proximal small intestine. However, the underlying signaling cascade that free fatty acids initiate in these enteroendocrine cells, which leads to secretion of satiety hormones, is not known. In general, my research is focused on identifying nutrient-responsive …

Inducing A Normal Phenotype In Breast Epithelial Cells Using A Three-Dimensional Basement Membrane Extract Culture System: A Study On The Reversion Of Cancer, Ross H. Booth

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Experimentally, traditional developmental models and transgenic animals consistently underscore the importance of studying cell behavior in the correct tissue context. However, live animal experimentation is inherently complex, and systematic assessment of the effects of individual variables, such as cell shape and matrix compliance on cell behavior, is extremely difficult at best. Two-dimensional monolayer culture of key individual cell types has provided abundant, fundamental information on cell response, but cannot be used to show the normal phenotype of breast epithelial cells. Furthermore, their results often fail to translate into in vivo and clinical studies. It has been previously established that normal …

The Use Of Reverse Genetics To Clone And Rescue Infectious, Recombinant Human Parainfluenza Type 3 Viruses, Jason Peter Roth

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Reverse genetics is a discipline that involves the use of genetic manipulation and modification to study an organism's altered phenotype. In this study, infectious recombinant viruses were rescued from altered cDNA clones encoding the antigenome of human parainfluenza virus type 3 and the resulting phenotypes were examined. In one clone, the gene for the enhanced green fluorescent protein was inserted into the virus antigenome to be expressed during viral replication, resulting in infected cells emitting green fluorescence. Viral titers, mRNA replication, and genomic replication for the virus expressing the enhanced green fluorescent protein were reduced when compared to the human …

Greater Sage-Grouse And Energy Development In Northeastern Utah: Implications For Management, Leah Suzanne Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Concern regarding the effect of energy development on greater sage-grouse (Centrocercus urophasianus) is increasing as the search for fossil fuel intensifies. Sage-grouse may be especially sensitive to energy development because they require large, diverse areas of sagebrush (Artemisia spp.) habitat to complete their life cycle. Additionally, the network of pipelines, roads, and wells required by energy development may fragment sagebrush habitat isolating populations and contributing to genetic drift, inbreeding, local extinction, or rapid divergence.

Seep Ridge, located in northeastern Utah, is one area where sage-grouse habitat and energy development plans overlap. Approved leases call for the construction …

Application Of Electrified Fladry To Decrease Risk Of Livestock Depredation By Wolves (Canis Lupus), Nathan J. Lance

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wolf (Canis lupus) predation on livestock can cause economic and emotional hardships for livestock producers, complicating the balance of wolf conservation with other human interests. New management tools that decrease risk of predation may offer additional flexibility or efficiency for both livestock producers and management agencies. I examined 1) the efficacy of electrified fladry compared to fladry at protecting a food source from wolves in captivity, 2) the efficacy of electrified fladry for reducing wolf use of pastures and preventing depredations, and 3) the applicability of electrified-fladry. In captivity I tested the reaction from 15 groups (46 wolves) …

Evaluation Of Macroinvertebrates As A Food Resource In The Assessment Of Lotic Salmonid Habitat, Nicholas P. Weber

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Criteria used to characterize lotic salmonid habitat are often based on observed correlations between physical habitat characteristics and salmonid abundances. A focus on physical habitat features ignores other habitat components, such as an adequate supply of food that set the physiological limitations on salmonid growth and survival. This study outlines the development of a habitat assessment approach that focuses on how invertebrate food availability interacts with stream temperatures to determine salmonid growth potentials. Abundances of benthic and drifting invertebrate communities, stream temperatures, and juvenile steelhead trout (Onchorhynchus mykiss gairdneri) summer growth rates and abundances were measured within 10 …

Surgical Sterilization Of Coyotes To Reduce Predation On Pronghorn Fawns, Renee Seidler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Coyote (Canis latrans) predation accounts for the majority of neonatal pronghorn (Antilocapra americana) mortality in many areas and may influence local population declines. Current techniques used to manage coyote predation on wildlife species generally focus on lethal control methods. However, these methods may be controversial to the general public. Coyote sterilization is an alternative predation control method which is more acceptable to the public and has been shown to be effective in reducing sheep predation. We hypothesized that surgical sterilization of coyotes may increase pronghorn fawn survival; in the same way it reduces coyote predation on …

Characterization Of The Substrate Specificity And Mechanism Of Protein Arginine Methyltransferase 1, Whitney Lyn Wooderchak

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Protein arginine methyltransferases (PRMTs) posttranslationally modify protein arginine residues. Type I PRMTs catalyze the formation of monomethylarginine (MMA) and asymmetric dimethylarginine (ADMA) via methyl group transfer from S-adenosyl methionine onto protein arginine residues. Type II PRMTs generate MMA and symmetric dimethylarginine. PRMT-methylation affects many biological processes. Although PRMTs are vital to normal development and function, PRMT-methylation is also linked to cardiovascular disease, stroke, multiple sclerosis, and cancer.

Thus far, nine human PRMT isoforms have been identified with orthologues present in yeast, plants, and fish. PRMT1 predominates, performing an estimated 85% of all protein arginine methylation in vivo. Yet, the substrate …

Speciation, Species Concepts, And Biogeography Illustrated By A Buckwheat Complex (Eriogonum Corymbosum), Mark W. Ellis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The focus of this research project is the complex of infraspecific taxa that make up the crisp-leaf buckwheat species Eriogonum corymbosum (Polygonaceae), which is distributed widely across southwestern North America. This complex provides an ideal taxonomic group for research into population relationships and speciation. To avoid unnecessary debates about taxonomic validity or contentious issues regarding appropriate species definitions, the historical evolution of the species concept is first reviewed in detail, demythologizing an often-assumed species problem. Following that review, the E. corymbosum complex is examined specifically.

Although eight varieties of E. corymbosum are currently recognized based on morphological characters, this group …

Linking Space Use And Behavior In Clark's Nutcracker: An Explanation For Seasonal Variation In Space Use, Teresa J. Lorenz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Clark's Nutcrackers (Nucifraga columbiana) are important seed dispersers for at least 10 species of conifer in western North America and are obligate mutualists for the subalpine tree, whitebark pine (Pinus albicaulis). Despite the important role they play in forest regeneration, space use by nutcrackers has not been formally studied. Several hypotheses exist to explain their year-round space use patterns. I tested one hypothesis that Clark's Nutcrackers migrate altitudinally between summer and autumn in one population in the Cascade Range, Washington. In 2006 and 2007, I compared seasonal differences in summer and autumn space use by 26 …

A Study On The Mechanisms Of Mercury Tolerance In The Cyanobacterium, Synechococcus Sp. Iu 625, Winder Bienvenido Perez

Theses, Dissertations and Culminating Projects

Synechococcus sp. IU 625 (Anacystis nidulans) is a freshwater unicellular cyanobacterium and an obligate photoautotroph that readily harbors plasmids. This organism has been used in many studies to assess the effect of heavy metal toxicity as an environmental pollutant. In one of the few studies for strain IU 625, Simon isolated 4.7- MDa and 37-MDa plasmids in 1978. The relationship between these plasmids and the 7.6-kb and 46.6-kb plasmids of strain PCC 7942 is unknown. Primers designed based on the sequence of 46.6-kb plasmid pANL of PCC 7942 exhibited positive priming with isolated plasmid DNA from Syn. …

Spermiogenesis And In Vitro Culture Of Spermatogenic Cysts In Drosophila Pseudoobscura, Monicah Njogu

Seton Hall University Dissertations and Theses (ETDs)

Spennatogenesis is a complex process that involves differentiation and morphological changes of diploid stem cells into highly specialized, haploid, motile germ cells. Many of the transformative processes involved in mammalian spermatogenesis are conserved in flies, and their study would be facilitated by the availability of a reliable in vitro culture system. Culture of Drosophila melanogaster spermatogenic cysts is limited in usefulness because of early degeneration of cysts, low yield of elongated spermatozoa, and rare occurrences of motile sperm. We have developed a culture system for studying fly spermatogenesis using isolated spermatogenic cysts from the testes of Drosophila pseudoobscura. This species …

Distribution And Site Selection Of Le Conte's And Crissal Thrashers In The Mojave Desert: A Multi-Model Approach, Dawn Marie Fletcher

UNLV Theses, Dissertations, Professional Papers, and Capstones

Information on the distribution and habitat requirements of a species are critical components to the development of meaningful conservation plans. Such knowledge, however, is particularly difficult to obtain for species that are elusive and occur at low densities, such as the Le Conte's ( Toxostoma lecontei ) and Crissal (Toxostoma crissale ) thrashers. In association with a regional conservation plan, I evaluated the distribution and habitat selection of these thrashers within Clark County, Nevada in the eastern Mojave Desert. I used a call-broadcast approach to sample 432 stratified random locations, detecting Le Conte's thrashers at 45 locations and Crissal …

Arid Climate Decomposition And Decay: A Taphonomic Study Using Swine, James William Munkres

UNLV Theses, Dissertations, Professional Papers, and Capstones

The present project analyzes the taphonomic processes and variables involved in the decomposition and desiccation of animal remains in an arid/hyper-arid environment. The study and the derived data will assist in determining postmortem intervals for remains in modern contexts, inform judgments made regarding mortuary habits and techniques in archaeological contexts, and will improve our knowledge regarding taphonomic processes. Manner of deposition, the depositional surface/medium and arid-climate specific variables (temperature, water, insect activity, weathering, pH levels, and soil characteristics) were examined in this study. Reported observations are limited to the first ten months following death from early December through early October …

Stress Responses To Salinity In A Native Fresh Water Snake (Nerodia Rhombifer), Joana A. Cordoba

Theses and Dissertations - UTB/UTPA

Salinity stress at 0 ppt, 9 ppt, 18 ppt, and 27 ppt was investigated in Nerodia rhombifer, a fresh water snake. The purpose of this study was to establish if exposure to salinity could elicit a hormonal response in the form of corticosterone. Salinity treatment 27 ppt was lethal for 50% of the snakes. Factors such as population and gender differences were not significant, p=0.748 and p=0.135, respectively. Exposure to the different salinities did not significantly affect the overall mass of the animal, p=0.951. A significant increase in circulating corticosterone was noted in salinity treatments 0 ppt and 18 ppt, …

Transcriptomic Analysis Of The Entomopathogenic Nematode Heterorhabditis Bacteriophora Tto1, Byron J. Adams, Xiaodong Bai, Todd A. Ciche, Sandra Clifton, Randy Gaugler, Parwinder S. Grewal, Saskia A. Hogenhout, John Spieth, Paul W. Sternberg, Richard K. Wilson

Faculty Publications

Background: The entomopathogenic nematode Heterorhabditis bacteriophora and its symbiotic bacterium, Photorhabdus luminescens, are important biological control agents of insect pests. This nematode-bacterium-insect association represents an emerging tripartite model for research on mutualistic and parasitic symbioses. Elucidation of mechanisms underlying these biological processes may serve as a foundation for improving the biological control potential of the nematode-bacterium complex. This large-scale expressed sequence tag (EST) analysis effort enables gene discovery and development of microsatellite markers. These ESTs will also aid in the annotation of the upcoming complete genome sequence of H. bacteriophora. Results: A total of 31,485 high quality ESTs were generated …

Analyzing The Interconnectedness Between Space, Place, And Human Interaction With The Natural Environment: "Ecological Reawakening: Organic Dna And Evolution", Sarah Moos

Scripps Senior Theses

I have organized this paper into four chapters: "The Environmental Situation," "Space and Place," "Art and the Natural Environment," and "Creating Work of My Own." Chapter 1 explains human beings' intrinsic interconnection to the natural environment, outlining why humans should be concerned about the current degraded state of the natural world. Chapter 2 discusses the concepts of space and place. It analyzes how human beings interact with and experience spaces, developing their sense of place - within physical, theoretical, and spiritual realms. It finally illustrates the importance that spaces and places have in humans' lives. Chapter 3 describes the Land …

An Analysis Of The Environmental And Hormonal Effects On The Growth And Development Of The Moss Ceratodon Purpureus, Megan Knight

Undergraduate Honors Thesis Collection

Ceratodon has not been documented in scientific literature as thoroughly as other species of moss such as Funaria or Tortula. Commonly known as fire moss or purple horned moss, Ceratodon is often reddish or yellow-brown and the spore capsules are usually purple (Crum, 1983). A picture of the species growing in its natural habitat is shown in Figure 4. Ceratodon often grows in tufts and is considered a weed, often thriving in polluted or disturbed areas and frequently invading after a fire (Crum 1983). Ceratodon belongs to the class Bryopsida, which also contains the previously mentioned Funaria and Tortula species. …

Lead Bullet Fragments In Venison From Rifle-Killed Deer: Potential For Human Dietary Exposure, W. Grainger Hunt, Richard T. Watson, J. Lindsay Oaks, Chris N. Parish, Kurt K. Burnham, Russell L. Tucker, James R. Belthoff, Garret Hart

Biology Faculty Publications and Presentations

Human consumers of wildlife killed with lead ammunition may be exposed to health risks associated with lead ingestion. This hypothesis is based on published studies showing elevated blood lead concentrations in subsistence hunter populations, retention of ammunition residues in the tissues of hunter-killed animals, and systemic, cognitive, and behavioral disorders associated with human lead body burdens once considered safe. Our objective was to determine the incidence and bioavailability of lead bullet fragments in hunter-killed venison, a widely-eaten food among hunters and their families. We radiographed 30 eviscerated carcasses of White-tailed Deer (Odocoileus virginianus) shot by hunters with standard …

Developmental Changes In Zebrafish Embryos Exposed To Bisphenol A Leeched From Commonly Used Plastics, David L. Ortiz

Senior Honors Theses

Bisphenol A, an estrogen mimicker, is found in the commonly used plastic, polycarbonate. Zebrafish embryos were raised in water that had been heated in polycarbonate water bottles by either microwaving for 5 minutes, or boiling for one hour. Near total mortality was seen in 7 days for the embryos growing in bottle-microwaved water, and 9 days for those raised in bottle-boiled water. Zebrafish embryos were also grown in the following known concentrations of BPA: 2mg/l, 14mg/l, 16mg/l, 50mg/l, 135mg/l, and 235mg/l. A stepwise relationship between concentration of BPA and embryo lifespan was seen, and the lowest observed adverse effect level …

The Presence Of Amphibian Ranavirus In Virginia Warm Water Fish Hatchery Ponds, Elizabeth Nelson

Theses and Dissertations

Amphibian declines have been occurring world wide over the past several decades. Infectious disease and environmental changes have been implicated as the causative agents in these declines. Fish stocking from hatcheries provides a unique opportunity for organisms, including infectious diseases, to travel over long distances. Ranavirus was previously found in two ponds at Harrison Lake National Fish Hatchery in Charles City County, Virginia. Therefore, the primary objective of this study was to determine if ranavirus is present in tadpoles from four warm water fish hatcheries in Virginia. A secondary objective of this study was to determine if there are relationships …

From In-Vitro To In-Vivo: Corporate Development And Efficacy Of A Topical Hair Growth Agent Derived From Natural Extracts, Kelly Michael Glynn

Masters Theses

Androgenetic alopecia (male pattern baldness) affects up to 50% of the world’s population, propelling the development for a possible treatment. The hair follicle is influenced by several genetic and physiologic factors, which, when gone awry, lead to androgenetic alopecia. Vascular endothelial and keratinocyte growth factors are believed to be promoters of hair growth, as is inhibition of the proteasome complex. The cytokine IL-1α is also known to regulate follicle dynamics. The research objective described herein was an attempt to develop a botanical blend, which could mediate the above biomarkers, be successfully incorporated into a safe topical product and be evaluated …

Molecular Systematics Of Spiny Pocket Mice (Subfamily Heteromyinae) Inferred From Mitochondrial And Nuclear Sequence Data, Melina Crystal Williamson

Theses and Dissertations

This study aims to determine species-level relationships within the genus Heteromys, as well as generic-level relationships among members of the subfamily Heteromyinae using a phylogenetic framework. Molecular sequence data were generated from two mitochondrial genes (cytochrome b and cytochrome oxidase I) and three nuclear gene segments (β-fibrinogen, engrailed protein II, and myosin heavy chain II), and analyzed under maximum parsimony, maximum likelihood, and Bayesian optimality criteria to infer relationships. Chapter 1 focuses on the phylogenetic and taxonomic implications for Heteromys from the analyses of sequence data. Phylogenies also provided a framework for delimiting species boundaries within the wide-ranging Heteromys desmarestianus …

The Role Of Mitogen-Activated Protein Kinases In The Regulation Of Plant Development, Erica Satterfield

Theses and Dissertations

Mitogen-activated protein kinases are part of an evolutionarily conserved protein phosphorylation cascade which serves essential regulatory functions in eukaryotic organisms. Although the role of MAPKs in the regulation of a plant’s response to environmental stress and plant defense has been well established, very little is known about their role in the regulation of plant developmental processes. In order to examine the role of MAPKs in plant growth and development, a strong mammalian MAPK phosphatase (MKP-1), which is known to inactivate MAPKs in plants, was introduced into tobacco plants. In tobacco plants, MKP-1 overexpression altered plant responses to the phytohormones, ethylene …

My 20-Year Research Journey For A New Species Of Spiders, Or How To Come To A New Discovery, Vladimir Ovtcharenko

Touchstone

From time to time students ask me whether it is difficult to discover new species of organisms on our planet. To answer this question, I have decided to tell my story of how I discovered a new species of spider that I have dedicated to Eugenio María de Hostos.

Modeling Brain Injury: Expression Of Glial Fibrillary Acidic Protein In Stretch-Injured Astrocytes, Lindsey Cooke

Undergraduate Theses and Capstone Projects

Traumatic brain injury (TBI) is the leading cause of death and disability in individuals under 45. Individuals who survive TBI may be disabled for the rest of their lives and suffer from cognitive, physical, social and financial problems. Following TBI it has been shown that astrocytic gene expression of many proteins, including glial fibrillary acidic protein (GFAP), increases. These “reactive” astrocytes are thought to have both beneficial and detrimental effects on neuronal survival and function. The current study uses an in vitro model of injury which grows astrocytes on deformable silastic membranes to allow for dynamic stretch of cultured cells …

Integrated Fisheries Management. Allocation Report Roe's Abalone Resource Perth Metropolitan Region., Integrated Fisheries Allocation Advisory Committee

Fisheries Management Papers

The introduction of Integrated Fisheries Management (IFM) is a recent development in the management of fisheries in Western Australia. IFM is an initiative aimed at addressing the issue of how fish resources in Western Australia can be best shared between competing users within the broad context of “Ecologically Sustainable Development”, or ESD.

Linking Wildlife Populations With Ecosystem Change: State-Of-The-Art Satellite Ecology For National-Park Science, Mark Hebblewhite

Biological Sciences Faculty Publications

As human impacts increase in national parks and the greater ecosystems surrounding them, the National Park Service faces the difficulty of monitoring ecosystem changes and responses of key wildlife indicator species within parks. Responses of bison to trail grooming in Yellowstone National Park (Wyoming, Montana, and Idaho) and control of the animals once they leave the park (Bruggeman et al. 2007), migration of wildlife across park boundaries (Griffith et al. 2002; Berger 2004), effects of restored wolves on vegetation communities through trophic cascades (Hebblewhite et al. 2005), and responses of wildlife to the use of prescribed fires all represent problems …

Fisheries Occasional Publication No. 67 - Review Of Fisheries Research Report (177), Aldo Steffe, Department Of Fisheries Western Australia

Fisheries Occasional Publications

To provide a review of the Research Report (177) on recreational boat-based fishing in the West Coast Bioregion during 2005/06 including: • The appropriateness of the basic creel survey design used for deriving estimates of catch, effort and catch rates for this type of fishery. • An assessment of whether the assumptions, scope and omissions were suitably identified. • The robustness of the catch estimates, and any conclusions that were included in the report, and total and seasonal recreational catch estimates. These initial terms of reference were expanded to include some discussion on issues raised by (a) the WA Fisheries …