Digital Commons Network^™

Terrestrial Ecosystem Classification In The Rocky Mountains, Northern Utah, Antonin Kusbach

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Currently, there is no comprehensive terrestrial ecosystem classification for the central Rocky Mountains of the United States. A comprehensive classification of terrestrial ecosystems in a mountainous study area in northern Utah was developed incorporating direct gradient analysis, spatial hierarchy theory, the zonal concept, and concepts of diagnostic species and fidelity, together with the biogeoclimatic ecosystem classification approach used in British Columbia, Canada.

This classification was derived from vegetation and environmental sampling of both forest and non-forest ecosystems. The SNOwpack TELemetry (SNOTEL) and The National Weather Service (NWS) Cooperative Observer Program (COOP) weather station network were used to approximate climate of …

Targeting Fatty Acid-Activated Pathways In The Somatosensory System, Tian Yu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Given the dramatic rise in obesity and the diseases linked with it, it is becoming increasingly important to understand the mechanisms that underlie the body's ability to recognize fat. The chemoreception of dietary fat in the oral cavity has largely been attributed to activation of the somatosensory system that relays the textural properties of fat. However, the ability of fatty acids, which are believed to represent the proximate stimulus for fat taste, to activate trigeminal ganglionic neurons has remained unexplored. In general, my research has provided the first evidence of fatty acids activating the somatosensory system by increasing the intracellular …

Nga Whaiora Tikanga Roanga: Māori Views Of Health In Utah, Sydney H. Davies

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study looked at the health beliefs of Māori who live in Utah, U.S. and examined what ways those beliefs have evolved from traditional Māori health beliefs. It also looked at the conditions and indicators of those conditions that maintain those health beliefs. A New Zealand study found that Māori older than age 45 years were more likely to have traditional health beliefs, whereas Māori younger than age 45 were more likely to have western-based health beliefs. Using grounded theory, the narratives—from two groups, younger or older than 45 years, where each group was composed of eight randomly selected participants—were …

Greater Sage-Grouse Response To Sagebrush Reduction Treatments In Rich County, Utah, Roger Blair Stringham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Management of greater sage-grouse (Centrocercus urophasianus) in the west has changed over the last several decades in response to environmental and anthropogenic causes. Many land and wildlife management agencies have begun manipulating sagebrush with herbicides, machinery, and fire. The intent of these manipulations (treatments) is to reduce sagebrush canopy cover and increase the density of grass and forb species, thus providing higher quality sage-grouse brood-rearing habitat. However, monitoring of sage-grouse response to such manipulations has often been lacking or non-existent. The objective of our study was to determine the response of sage-grouse to sagebrush reduction treatments that have …

Ecology Of Isolated Greater Sage-Grouse Populations Inhabiting The Wildcat Knolls And Horn Mountain, Southcentral Utah, Christopher J. Perkins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Greater sage-grouse (Centrocercus urophasianus) currently inhabit about 56% of pre-settlement distribution of potential habitat. In 2005, the Castle Country Adaptive Resources Management Local Working Group (CaCoARM) was formed to address concerns regarding local sage-grouse populations in Carbon and Emery counties. In 2006-2007, CaCoARM identified the Wildcat Knolls and Horn Mountain as areas of special concern for greater sage-grouse conservation. Both sites selected by the group were inhabited by what appeared to be small isolated sage-grouse populations. Factors limiting small isolated greater sage-grouse populations throughout its range are diverse and largely site-specific.

During 2008-2009, I captured, radio-collared, and monitored …

Natural History And Breeding System Of Maguire Primrose, Jacob B. Davidson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The goal of this thesis was to examine the breeding system and natural history of the Maguire primrose (Primula cusickiana var. maguirei). Maguire primrose is an endemic, threatened subspecies found only along a narrow corridor within Logan Canyon in northern Utah, USA. This plant displays distinct flower distyly, with clear distinction of pin and thrum morphologies (morphs). The timing of Maguire primrose flower blooms was disparate between upper and lower canyon populations, and the flowers experienced cool temperatures occasionally. I captured eight different species of flying insects visiting Maguire primrose flowers, and made 67 observations of insect visitation. …

The Effect Of In-Line Lakes On Dissolved Organic Matter Dynamics In Mountain Streams, Keli J. Goodman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research combines observation, experimentation, and modeling to evaluate the influence of lakes on dissolved organic matter (DOM) quantity, quality and export in subalpine watersheds of the Sawtooth Mountain Lake District, central Idaho.

First, I conducted an empirical study of the hydrologic and biogeochemical controls on DOM dynamics in stream-lake fluvial networks. I hypothesized that lakes would decrease temporal variability (i.e., buffer) and alter the characteristics of DOM from inflow to outflow. I tested these hypotheses by evaluating DOM temporal patterns and measuring annual export in seven-paired lake inflows and outflows. I then evaluated how ultraviolet (UV) exposure affected DOM …

Modeling Bark Beetle Outbreak And Fire Interactions In Western U.S. Forests And The Invasion Potential Of An Invasive Puerto Rican Frog In Hawaii Using Remote Sensing Data, Simon A. Bisrat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I used Moderate-Resolution Imaging Spectroradiometer (MODIS) imagery to answer two ecological questions. In the first project, I investigated the interactions between bark beetle-caused tree mortality and fire occurrence in western U.S. forests. I used remotely sensed fire data detected by MODIS satellite and bark beetle-caused tree mortality data. I tested the hypothesis that there is an increased probability of fire incidence in bark beetle-damaged forests compared to healthy forests using conditional probability modeling across the national forests of the western U.S. regardless of forest type. My results did not show a consistent pattern (increase or decrease of conditional probability of …

Role Of Protein Kinase C Isotypes In 1,25-Dihydroxyvitamin D3 Mediated Signal Transduction Through The 1,25d3 Membrane Associated, Rapid Response Steroid Binding Receptors In Chick Intestinal Cells, Sakara Tunsophon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

It is now accepted that 1,25(OH)2D3 mediates its rapid actions on the control of phosphate and calcium homeostasis through its membrane receptor termed the 1,25D3-MARRS (membrane associated rapid response steroid binding) protein. I determined the various PKC isotypes involved in the rapid regulation of phosphate uptake and calcium extrusion in chick intestinal cells. 1,25(OH)2D3-mediated phosphate uptake was stimulated within 1 min after addition of the hormone. Western blot analyses on isolated intestinal cells treated with steroid hormone resulted in dose-dependent increases in PKC alpha and PKC beta in postnuclear centrifugation fractions, but not in the low speed centrifugation fractions. The …

A Multi-Scale Evaluation Of Pygmy Rabbit Space Use In A Managed Landscape, Tammy L. Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Habitat selection has long been viewed as a multi-scale process. Observed species responses to resource gradients are influenced by variation at the scale of the individual, population, metapopulation, and geographic range. Understanding how species interact with habitat at multiple levels presents a complete picture of an organism and is necessary for conservation of endangered species. The main goal of this dissertation is to evaluate distribution, relative abundance, and habitat selection of a rare species, the pygmy rabbit Brachylagus idahoensis, at multiple scales in order to improve management and conservation for this species.

At the broadest scale, pygmy rabbit occurrence …

Greater Sage-Grouse Seasonal Ecology And Responses To Habitat Manipulations In Northern, Utah, Eric T. Thacker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Declining greater sage-grouse populations (Centrocercus urophasianus; hereafter sage-grouse) have led to increased concern regarding the long-term stability of the species. Previous research has identified factors contributing to the observed population declines. Habitat degradation and loss have been implicated as major factors in population declines. Although much is known about sage-grouse biology, more information is needed about population responses to specific management actions. This research was conducted to document sage-grouse responses to site-specific management actions. Additionally, I evaluated sage-grouse temporal and seasonal habitat-use and the comparability of techniques used by range and wildlife managers to measure vegetation responses of …

Library Synthesis Of Anticancer And Antibacterial Agents Via Azide Chemistry, Jianjun Zhang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Various anticancer and antibacterial agents have been synthesized via azide chemistry by taking advantage of carbohydrate. Starting from the synthesis of 14 glycosyl azides, a library of carbohydrate-oxazolidinone conjugates and a library of carbohydrate-cyclopamine conjugates with biological interests were synthesized based on a highly efficient "click reaction" assisted by sonication. Some of the conjugates have improved solubility and enhanced anticancer activity.

A library of neomycin B derivatives with various modifications at the 5" position has been synthesized. Two leads exhibit prominent activity against both methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). Antibacterial activities were measured when combined with other …

The Influence Of Collective Action And Policy In The Development Of Local Food Systems, Lori Porreca

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The modern global agrifood system has had significant negative impacts on consumers and producers. This has precipitated the rise of local food systems that are purported to improve the health and livelihoods of consumers and producers. High expectations have led to significant public and private resources dedicated to the development of local food systems. Despite this, there has been little systematic research exploring the social and institutional conditions that facilitate or frustrate local food system development.

Using a comparative case study approach, this study explored the ways local structural conditions, collective action, food system policies, and the political context affect …

The Hypericum Perforatum Herb As An Antimycobacterial Agent And Its Implications As An Additional Tuberculosis Medication, Trent W. Mortensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An immediate demand exists for new tuberculosis (TB) antibiotics due to the ever-increasing spread of drug-resistant strains. The drug-development process goes through four phases, the first (Phase 0) of which is to demonstrate and investigate drug effectiveness and toxicity. This research investigated the effectiveness of the Hypericum perforatum herb (commonly St. John's wort (SJW)) in its growth inhibition of mycobacteria and its viability effect on human lung cells.

Organic-solvent SJW extracts were effective at inhibiting every nonpathogenic genetically sequenced Mycobacterium isolate currently available (six isolates) in preliminary studies. Quantitative studies of five Mycobacterium isolates showed an order of concentration sensitivity …

The Evolution And Implementation Of An Integrated Approach To Emotionally Focused Couple Therapy: A Case Study, Heather Thompson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

There are a number of advantages to working within an integrated model framework when doing family therapy; however, few therapists test what they articulate as their model against what they really do. The purpose of this study was to test how well one therapist practiced her explicated theoretical integration in a clinical setting. Quantitative and qualitative data were gathered to answer three research questions: the level of adherence to the integration, client change, and change within the integrated model over the course of the study. The sample included three couples; data from 25 video-coded sessions, the Revised Dyadic Adjustment Scale …

The Influence Of Landscape And Weather On Foraging By Olfactory Meso-Predators In Utah, Rebekah E. Dritz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Predation by olfactory meso-predators has a large impact on avian nest success, particularly for ground-nesting waterfowl. Olfactory predators rely on odors to locate their prey. Weather conditions (e.g. wind speed, humidity, and temperature), vegetation, and landscape features affect the dissipation rate of odors and could affect the foraging efficiency of olfactory predators. I conducted 2 studies to determine if weather and landscape impact predator foraging ability and behavior: a predator survey study and an artificial nest study. The objective of the predator survey was to investigate how landscape and weather conditions interact to influence the distribution of olfactory meso-predators [e.g. …

Asymmetric Interspecific Competition Between Specialist Herbivores That Feed On Tamarisk In Western Colorado, Nina P. Louden

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Four closely related species of leaf beetles (Diorhabda spp.; Coleoptera: Chrysomelidae) have been introduced into the western United States as biocontrol agents for the invasive Eurasian shrub tamarisk (Tamarix spp.; Violales: Tamaricaceae). These beetles have since continued to spread and establish throughout the western United States. Another exotic insect, the tamarisk leafhopper (Opsius stactogalus, Fieber; Hemiptera: Cicadellidae), had previously become established in these areas and now shares tamarisk as a host plant with the beetles. To assess more carefully the potential for interactions between leafhoppers and beetles, field censuses and cage studies were conducted to determine …

Dancing With Heretics: Essays On Orthodoxy, Questioning And Faith, Darren M. Edwards

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

While much has been written about the conflicts, supposed or actual, between logic and faith, science and religion, few accounts of the personal turmoil these conflicts can cause exist. Likewise, many of these nonfiction accounts are written from a distinctly polarized place leaning either to science or faith.

In this thesis, I mix research and history with memoir and a sense of poetry to explore my personal experience with this conflict. At its outset, I hoped for this project to capture my struggle as an orthodox member of The Church of Jesus Christ of Latter-day Saints (LDS) in dealing with …

Survival Of Mycoplasma Species In Recycled Bedding Sand And Possible Implications For Disease Transmission To Ruminants, Anne E. Justice-Allen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mycoplasmas are a group of bacteria which are small in size, lack a cell wall, and have small genomes in comparison to other bacteria. The members of the group that are pathogenic utilize several mechanisms to evade the host's immune system. These processes affect surveillance and control mechanisms such as serologic testing and vaccination. Many of these organisms cause diseases of livestock, which heavily impact production parameters such as weight gain, milk yield, and egg production. Mycoplasmas also cause disease in people.

Mycoplasma spp. can cause mastitis, metritis, pneumonia, and arthritis. The currently documented routes of transmission of Mycoplasma spp. …

A Criterion For Identifying Stressors In Non-Linear Equations Using Gröbner Bases, Elisabeth Marie Palchak

Honors Theses

No abstract provided.

Biological And Mechanical Approaches To Sunscald Management In Bell Pepper Production, Samuel D. Day

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Producing red bell peppers in high temperature and light environments can be challenging because many new semi-indeterminate varieties produce small plant canopies that leave fruit exposed to damage (sunscald) caused by solar radiation. Pepper production in Utah coincides with high air temperatures and solar radiation levels during July, August, and September. Increasing plant canopy size is one way to protect fruit from solar radiation. Low tunnels optimize plant growth by increasing air and soil temperatures. Growing plants under low tunnels early in the season could increase fruit shading later in the season. Another way to protect fruit is by using …

Book Review: Gender And Hiv/Aids: Critical Perspectives From The Developing World, Cassandra R. Warren

Journal of International Women's Studies

Review of Gender and HIV/AIDS: Critical Perspectives from the Developing World, edited by Jelke Boesten amd Nana K. Poku

Farnesol Signaling In Candida Albicans, Melanie L. Langford

School of Biological Sciences: Dissertations, Theses, and Student Research

Candida albicans is a polymorphic fungus that causes a range of disease in humans, from mucosal infections to systemic disease. Its ability to cause disease is linked to conversion between yeast and filamentous forms of growth, and the first quorum-sensing molecule discovered in an eukaryote, farnesol, blocks this transition. In C. albicans, farnesol also kills mating-competent opaque cells, inhibits biofilm formation, protects the cells from oxidative stress, and can be a virulence factor or protective agent in disseminated and mucosal mouse models of infection, respectively. While much emphasis has been placed on determining its effect on C. albicans morphology, …

Ecology And Relationships Of Rhabdias Spp. (Nematoda: Rhabdiasidae) From North American Amphibians And Reptiles, Gabriel J. Langford

School of Biological Sciences: Dissertations, Theses, and Student Research

Lungworms of the cosmopolitan genus Rhabdias (Nematoda: Rhabdiasidae) are among the most common parasites of amphibians and squamate reptiles. The life cycles, life histories, host specificities, and evolutionary relationships of Rhabdias spp. were studied through examination of their free-living and parasitic stages in amphibians and reptiles. This study found free-living development of anuran lungworms was primarily limited to heterogonic reproduction, whereas snake lungworms primarily reproduced homogonically. Infective anuran lungworms penetrated the skin of frogs and toads; in contrast, snake lungworms penetrated snake esophageal tissue during per os infections. Our molecular phylogeny strongly supported separate clades for anuran and snake lungworms, …

A Guide To The Continuing Investigation Of The Relationship Between The Cytoskeleton And Cell Wall In Developing Buds Of Physcomitrella Patens, Derek Brockman

Senior Honors Projects

Persistent questions in biology address the nature of tissue organization and how information encoded in the genome can be manifested as a physical form. While the ‘final’ product of gene expression is a protein, science has yet to elucidate how those proteins are able to interact with other cellular components and external forces to generate a specific cell shape. This complex process is critical in determining not only the shape of an individual cell but also that of an entire organ. In plants, cell shape is controlled by cellulose microfibrils of the cell wall, which are typically oriented perpendicular to …

Citrate Synthase And The Visual Interactions Hypothesis, Kristina Camarena

Senior Honors Projects

It has been shown that the metabolic rates of deep-living species of particular pelagic groups are significantly lower than those that live closer to the surface in the water column. Various theories as to why have been presented, including the visual interactions hypothesis, which states that because there is a greatly minimized ability to visually interact in the light-limited deep, predators have a reduced need for high metabolic rates because they do not actively go after their prey. Citrate synthase is a mitochondrial enzyme found at the beginning of the citric acid cycle, which plays an integral role in cellular …

The Tale Of Mental Causation: Fact Or Fiction?, Chia-Lin Tu

Dissertations

Mental causation is with us all the time. Being a table is different from being a human---although we are composed of physical particles, we have understanding, reason, or perception, which are able to make a difference in the physical world. In this dissertation, I have detail discussions of contemporary substance dualism, the mind-brain identity theory, and Jaegwon Kim's functionalism, and thus conclude that none of them can provide an appropriate account to the problem of mental causation. By distinguishing the mind from the body, substance dualists face the pairing problem: How does this particular mind unite with this particular body …

Genes Involved In Mushroom Body Development And Behavior In Drosophila, Christine Nicole Serway

UNLV Theses, Dissertations, Professional Papers, and Capstones

Mushroom bodies (MBs) are the site of multi modal sensory integration critical for associative conditioning in Drosophila. They have been central to research on the structure function relationship in the brain for over one hundred years due to their unique shape and readily accessible physiology. This dissertation incorporates three different approaches to further elucidate the genetic and molecular nature of this structure function relationship.

First, the suite of genetic and molecular tools available in Drosophila melanogaster, facilitated the molecular mapping of a 25-year old MB structural mutant called mushroom body miniature B (mbmB) to the gene Pendulin [Pen, also known …

An Evaluation Of Lead In Imported Candies Within Clark County, Nevada, Usa, Lee Reuben Ibarra

UNLV Theses, Dissertations, Professional Papers, and Capstones

Imported candies from Latin America pose a danger to children because of the potential for those candies to contain harmful levels of lead. This study sought to identify characteristics of imported candies that typically display higher concentrations of lead. This study also explored the Integrated Exposure Uptake Biokinetic model developed by the EPA. Using lead exposure data specific to Clark County, Nevada, the IEUBK model was used to estimate the amounts of candy a child would have to consume in order to raise his blood lead level to over 10µg/dL (the federal allowable limit).

The results showed that candies with …

Cultural Competence Of Rn To Bsn Students, Dierdre Michelle Riley

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this exploratory research study was to examine the cultural competence of registered nurses returning to school for an RN to BSN program in Nevada. Campinha-Bacote's model, The Process of Cultural Competence in the Delivery of Healthcare Services, was used as a theoretical framework for the study. A secondary analysis of data collected as part of a Health Resources and Services Administration (HRSA) Grant was completed. Fifty-three RN to BSN students voluntarily completed the Inventory for Assessing the Process of Cultural Competency Among Healthcare Professionals- Revised (IAPCC-R) electronically in the learning management system of the first nursing course …