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Watershed-Scale Analysis Of Riparian Buffer Function, Molly Van Appledorn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The ability of riparian buffers to filter undesirable nutrients from upland sources has long been recognized as an important ecosystem service for maintaining or improving water quality, and as a result, many land management strategies have been built around the preservation or restoration of buffer zones. Newly derived flow-path metrics have shown great promise as a way to assess riparian buffer function at the watershed scale but a thorough investigation of metric performance was necessary. The goals of this study were to: 1) test the independence of flow-path metrics from traditional metrics using a spatially extensive, independent sample of watersheds, …

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) …

Social Acceptability Of Conifer Control And Sagebrush Restoration In The Northern Rocky Mountain Region, Cameron G. Nay

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the past two centuries, woody plant species have increased in density and extent throughout the rangelands of North America. This encroachment generally has undesirable effects on hydrological function, forest resources, and plant community composition. Encroachment of Douglas-fir (Pseudotsuga menziesii) and ponderosa pine (Pinus ponderosa) into sagebrush communities is occurring in the Northern Rocky Mountain region. Removal and restoration treatments are often proposed to manage this issue, mainly prescribed fire, mechanical destruction, and/or herbicide use. Several contextual factors may affect public level of acceptability for such treatments. The issue frames used to present this problem to …

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 …

Taste Sensitivity To 6-N-Propylthiouracil (Prop) As A Biological Marker For Vulnerability To Stress In Mothers And Children, Deann Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Some people are genetically more vulnerable to stress than others, leading them towards poorer outcomes following stressful events. Mothers' vulnerability to stress may, in turn, influence their children, leading their children towards poor outcomes as well. A biological marker of vulnerability to stress may indicate mothers who are at greater risk for experiencing parenting stress, depression, and less support of the infant's emotional development, and infants who are at greater risk for development of poor emotion regulation and behavior problems. Taste sensitivity to propylthiouracil (PROP) is proposed as a biological marker of stress vulnerability in mothers and children. This research …

Microbial Growth Inhibition And Decomposition Of Milk Mineral And Sodium Tripolyphosphate Added To Media Or Fresh Ground Beef, Rossarin Tansawat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Milk mineral (MM) is a type II antioxidant (metal chelator) that can bind iron and prevent iron catalysis of lipid oxidation. Thus, MM might have microbial growth inhibition effects on iron-dependent bacteria. Objective 1 was to evaluate effects of MM on growth of non-pathogenic iron-dependent bacterial strains (Listeria innocua, Eschericia coli, Pseudomonas fluorescens). MM (1.5 % w/v) did not significantly inhibit growth of Listeria and E. coli. However, growth of Pseudomonas fluorescens was consistently and significantly reduced by ~1 log colony forming units per ml (CFU/ml) with all levels of MM (0.5, 0.75, 1.5 % …

Evolutionary Consequences Of The Introduction Of Eleutherodactylus Coqui To Hawaii, Eric Michael O'Neill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The introduction of a species to areas outside its native range can result in ecological and genetic changes of evolutionary significance. The frog Eleutherodactylus coqui was introduced to Hawaii, from Puerto Rico, in the late 1980s and has lost genetic variation in mitochondrial DNA. The extent to which founder effects have influenced phenotypic variation in the introduced range is unknown. In this study I compared phenotypic variation in life-history traits, advertisement calls, and stripe patterns among introduced and native populations of the frog Eleutherodactylus coqui. I also conducted laboratory experiments to determine the influence of genetics and temperature on …

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 …

Patch-Scale Effects Of An Invasive Ecosystem Engineer On The Structure And Function Of A Eutrophic Stream, Samuel J. Hochhalter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Recent theoretical and technological advances in ecosystem science have dramatically expanded the ways in which scientists can pursue and explore ecological questions. For my thesis research, I integrated the recent theoretical concept of organisms as ecosystem engineers with the relatively recent development of stable isotope tracer tests to ask the question: how does the invasive common carp affect stream ecosystem structure and function? To investigate the structuring role of carp, I measured autotroph seasonal distribution and abundance and macroinvertebrate seasonal abundance and diversity within two stream reaches in Spring Creek, Utah, USA; one with low carp biomass (LCB) and one …

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 …

Mycorrhizae In Sagebrush-Steppe Community Restoration: Mycorrhizal Dependency Of Invasive And Native Grasses With Intraspecific And Interspecific Competition, Dara S. Scherpenisse

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mycorrhizae have been used in restoration for decades. However, studies assessing the use of mycorrhizae in Bromus tectorum-invaded areas of the Great Basin are limited. Two greenhouse pot experiments were conducted to assess the role of mycorrhizae in sagebrush restoration.

The first objective (Chapter 2) was to determine the response of Pseudoroegneria spicatum, Elymus elymoides, and B. tectorum to mycorrhizal symbiosis by altering phosphorus, density, species, presence of mycorrhizae and water levels in a 5 factor design. To assess the mycorrhizal response, a variety of morphological and physiological traits were measured, such as tissue P concentration, specific …

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 …

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, …

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 …

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 …

Bioinformatic Study Of Snps And Phenotypes In Patients With Smith-Magenis Syndrome, Tyler Andrew Cox

Departmental Honors & Graduate Capstone Projects

Smith-Magenis Syndrome (SMS) is a human genetic disorder that is caused by either a deletion within chromosomal region 17p11.2 or a mutation of a gene in that region –the RAI1 gene. The most prominent phenotypes observed with this disorder are mental retardation, distinctive craniofacial features, and sleep disorders caused by an inverted pattern of serotonin secretion. The current methods for molecular detection of Smith-Magenis Syndrome are reliable for the detection of the deletions within chromosomal region 17p11.2, but are not reliable in detecting mutations with the RAI1 gene. One way to enhance the detection of RAI1 mutations is with the …

Molecular Characterization Of The Human Rai1 Promoter, Rose Irene Salzberg

Departmental Honors & Graduate Capstone Projects

Smith-Magenis syndrome (SMS) is a type of mental retardation disorder associated with a deletion of DNA from chromosome 17p11.2. It affects approximately18,000 individuals in the US alone. Major phenotypes are associated with a mutation in the Retinoic Acid-Inducible gene-1 (RAI1) and include: developmental delay, repetitive behaviors, short stature, and hoarse voice. Studying the molecular mechanisms that lead to SMS will help promote earlier detection of the disorder and will help develop a better treatment plan for patients. The purpose of this project was to characterize the promoter of RAI1. Studying the promoter of RAI1 will help determine the normal expression …

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 …