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Lead Risk Hazards In Pre-1978 Childcare Facilities Located In Clark County, Nevada, Usa, Jessica Marie Newberry

UNLV Theses, Dissertations, Professional Papers, and Capstones

The harmful health effects of lead exposure have been known for centuries, yet lead is still produced and utilized in a variety of ways. There have been many movements to rid the environment of this toxic metal in hope to reduce the number of individuals who are and who may potentially be exposed. Lead exposure is responsible for a myriad of negative health effects most notably lowering IQ scores in children. Extensive amounts of data have been collected from areas of the country with known lead hazards, hazards that have been identified through hundreds of thousands of elevated blood lead …

Health Status Of Infants And Children From The Bronze Age Tomb At Tell Abraq, United Arab Emirates, Kathryn Mary Baustian

UNLV Theses, Dissertations, Professional Papers, and Capstones

Tell Abraq is significant because it is the largest prehistoric site on the southern coast of the Arabian Gulf. It was strategically important as an ancient port, regionally surrounded by large political centers. Commingled remains were located in a small tomb (6 m) used for a 200 year period (2200-2000 BC). The site was continually occupied from the 3rd millennium BC up to the 1st century AD. In the tomb were minimally 286 adults and 127 subadults. What is extraordinary is the number of pre-term (3rd trimester) infants (n=28, 22%), neonates (n=12, 9%), and infants under 2 years (n=46, 36%). …

From Main-Travelled Roads To Route 66: Transitions In Prairie Naturalism, Michelle Nicole Munkres

UNLV Theses, Dissertations, Professional Papers, and Capstones

To best represent a people of a specific spatial and historical context, literary texts must necessarily demonstrate a vested interest and familiarity of a region and its inhabitants’ common experiences. In examining one particular aspect of regional naturalism in American literature, this study explores the basic tenets of Prairie Naturalism as defined by three major authors: Hamlin Garland, Willa Cather, and John Steinbeck. The short stories in Hamlin Garland’s Main-Travelled Roads (1891) establish the foundation of Prairie Naturalism with meticulous attention to daily lives on the plains and with political strategies to improve the lives of the oppressed. Willa Cather’s …

Second Language Inner Voice And Identity, Brandon Kenji Shigematsu

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study investigates the phenomena of second language (L2, hereafter) inner voice for three Japanese-American English bilinguals who had long-term exposure to the L2 in naturalistic contexts, that is, by living and/or working or studying in the U.S. American English learners of L2 Japanese were included in the study as well, although only one of them had naturalistic exposure, the other having traveled to Japan in addition to being married to a Japanese national. Data for the study reveals how and when L2 inner voice is utilized, how it appears to develop, how it leads to shifts in identity toward …

Phylogeography Of Two Closely Related Anurans, The Relict Leopard Frog (Rana Onca) And Lowland Leopard Frog (Rana Yavapaiensis), Viktoria Hemmings

UNLV Theses, Dissertations, Professional Papers, and Capstones

I investigate the phylogeography of the relict and lowland leopard frogs (Rana onca; R. yavapaiensis) inhabiting the Mojave and Sonoran deserts. In Chapter 1, I summarize literature describing taxonomy, phylogenetics, and the possible effects of Quaternary climate change on distribution. Examples of phylogeographic patterns from generally co-distributed organisms are provided to develop background for interpreting the structure. In Chapter 2, I investigate the phylogeography of these frogs using mitochondrial DNA data. The analysis supports a previously determined phylogenetic break between taxa however further dividing R. yavapaiensis into two lineages. I estimate a possible Early Pleistocene divergence of R. onca and …

African American And Caucasian Males' Evaluation Of Racialized Female Facial Averages, Rhea M. Watson

UNLV Theses, Dissertations, Professional Papers, and Capstones

The answer to what makes a face attractive has been debated for generations and studied in different disciplines. The current study investigated African American and Caucasian males' evaluation (attraction) to racialized female faces. Faces varied from 100% African American to 100% Caucasian (and included variations that were 25% of either group, or 50% of both groups). Twenty African American and 30 Caucasian men each viewed ten faces, and evaluated them in terms of their appearance and the likelihood that the men would interact with (befriend, date, or marry) the person pictured. Findings revealed that African American men found the 100% …

A Spatio-Temporal Analysis Of Landscape Change Within The Eastern Terai, India: Linking Grassland And Forest Loss To Change In River Course And Land Use, Tanushree Biswas

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Land degradation is one of the most important drivers of landscape change around the globe. This dissertation examines land use-land cover change within a mosaic landscape in Eastern Terai, India, and shows evidence of anthropogenic factors contributing to landscape change. Land use and land cover change were examined within the Alipurduar Subdivision, a representative of the Eastern Terai landscape and the Jaldapara Wildlife Sanctuary, a protected area nested within Alipurduar through the use of multi-temporal satellite data over the past 28 years (1978 – 2006).

This study establishes the potential of remote sensing technology to identify the drivers of landscape …

Perilous Pilgrimage: A Lady’S Flight Into The Rocky Mountain Wilderness, Jane Koerner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

“Perilous Pilgrimage: A Lady’s Flight into the Rocky Mountain Wilderness” is comprised of four thematically linked essays set in the Colorado Rockies. In these essays I probe my fascination with masculinity at an early age, the impact of my rape at age twenty-two, the dependency and resentment that undermined my marriage after the rape, and my quest after my divorce fifteen years later to define myself on my own terms. The link joining these strands is the tension between my drive for independence and my disassociation from my mind and body as a result of the rape.

“Perilous Pilgrimage” revisits …

Fundamentals Of Operation Of The Induced Bed Reactor (Ibr) Anaerobic Digester, Jacob Shaun Dustin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Induced Bed Reactor (IBR) was developed at Utah State University to apply high-rate anaerobic digestion techniques to high solids content substrates. This technology has been successfully implemented at full-scale multiple installations in the United States and Canada as a waste treatment and energy production technology, but the physical processes necessary to further optimize the system were not well understood.

Bench scale IBRs were operated as anaerobic digesters at 35°, 45°, and 55° C under three organic loading rates and three corresponding hydraulic retention times. Reactor performance was monitored at steady state for residence time distribution and substrate reduction.

The …

Mechanisms Of The Extreme Sensitivity Of Turkeys To Aflatoxin B1, Sumit Rawal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The pathogenesis of hepatotoxic and hepatocarcinogenic actions of the mycotoxin aflatoxin B1 (AFB1) involves initial bioactivation by microsomal cytochrome P450s (P450) to a reactive and electrophilic intermediate, exo-aflatoxin B1-8,9-epoxide (exo-AFBO). Poultry, especially turkeys, are extremely sensitive to AFB1, a condition associated with efficient epoxidation by P450s. The purpose of this research was to 1) discover and characterize the P450s in turkey liver responsible for AFB1 bioactivation, and 2) determine the relative importance of these P450s in turkey liver.

Initial investigations led to the discovery of CYP1A5. We then identified CYP3A37, a human CYP3A4 homologue from turkey liver, …

Physiological And Molecular Function Of Hap3b In Flowering Time Regulation And Cold Stress Response, Mingxiang Liang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Heme-activated proteins (HAPs) are transcription factors that have multiple roles in plant growth and development, such as embryogenesis, flowering time control, and drought tolerance.

In the present study I found that HAP3b was also involved in controlling response to cold stress. Transcript profiling and gene expression analyses indicated that HAP3b repressed the CBF3 regulon under normal growth conditions. As a result, plants with HAP3b-overexpressed showed decreased survival rates while plants homozygous for the null allele hap3b showed an improved freezing tolerance compared to wild-type plants.

To understand the mechanism of HAP3b in Arabidopsis, i.e. whether it also acts …

Altering Positive/Negative Interaction Ratios In Relationships Of Mothers And Young Children: A Preliminary Investigation, Andrew B. Armstrong

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Based on classic marital research of John Gottman, a popular notion exists that interpersonal relationships thrive when the number of positive interactions outweighs negative interactions by a ratio of five to one. Though many have given similar advice for parents and caregivers, Gottman's findings and methodology may not generalize to relationships of parents and young children. Were similar ratio findings to be validated for parent-child relationships, explicit ratio advice may be incorporated as a component of clinical practice (e.g., behavioral parent training). To begin investigating potential clinical implications, a project was conducted that examined mothers' ability to achieve prescribed ratios …

Water Allocation Challenges In Rural River Basins: A Case Study From The Walawe River Basin, Sri Lanka, D. K. Neelanga Weragala

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation evaluates the water allocation challenges in the rural river basins of the developing world, where demands are growing and the supply is limited. While many of these basins have yet to reach the state of closure, their water users are already experiencing water shortages. Agricultural crop production in rural river basins of the developing world plays a major role in ensuring food security. However, irrigation as the major water consumer in these basins has low water use efficiency. As water scarcity grows, the need to maximize economic gains by reallocating water to more efficient uses becomes important. …

Field And Smog Chamber Studies Of Agricultural Emissions And Reaction Products, Derek J. Price

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Agricultural emissions are an important contributor to atmospheric aerosol. These emissions include nitrogen containing organic compounds, primarily as amines, which have not been well investigated to date. Although there have been several studies that have looked at the emission of gas phase amines, there are only a few studies that have focused on ambient amine-based aerosol. There have also only been a handful of smog chamber studies that have investigated amine aerosol chemistry. Kinetic studies have looked at the reactions of amines with OH and ozone. However, amine reactions with nitrate radical (NO₃) are not well understood. Several …

Cooperative Remote Sensing And Actuation Using Networked Unmanned Vehicles, Haiyang Chao

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation focuses on how to design and employ networked unmanned vehicles for remote sensing and distributed control purposes in the current information-rich world. The target scenarios are environmental or agricultural applications such as river/reservoir surveillance, wind profiling measurement, and monitoring/control of chemical leaks, etc. AggieAir, a small and low-cost unmanned aircraft system, is designed based on the remote sensing requirements from environmental monitoring missions. The state estimation problem and the advanced lateral flight controller design problem are further attacked focusing on the small unmanned aerial vehicle (UAV) platform. Then the UAV-based remote sensing problem is focused with further flight …

Analysis Of Ammonia And Volatile Organic Amine Emissions In A Confined Poultry Facility, Hanh Hong Thi Dinh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The National Air Emission Monitoring Study (NAEMS) project was funded by the Agricultural Air Research Council (AARC) to evaluate agricultural emissions nationwide. Utah State University (USU) is conducting a parallel study on agricultural emissions at a Cache Valley poultry facility. As part of this parallel study, samples of animal feed, eggs and animal waste were collected weekly from three manure barns (designated: manure barn, barn 4 - manure belt and barn 5 - high rise) from May 2008 to November 2009.

These samples were analyzed to determine ammonia content, total Kjeldahl nitrogen content and ammonia emission. The yearly average calculated …

Reproductive Ecology Of Astragalus Filipes, A Great Basin Restoration Legume, Kristal M. Watrous

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Astragalus filipes Torrey ex. A. Gray (Fabaceae) is being studied and propagated for use in rangeland restoration projects throughout the Great Basin. Restoration forbs often require sufficient pollination services for seed production and persistence in restoration sites. Knowledge of a plant's breeding biology is important in providing pollination for maximal seed set.

Reproductive output from four manual pollination treatments (autogamy, geitonogamy, xenogamy, and distant xenogamy) was examined in a common garden. Pod set, seed set, and seed germination were quantified for each of the treatments. Seed set from four wild populations was compared to that of an openly visited common …

Plastic And Genetic Determination Of Population, Community, And Ecosystem Properties In Freshwater Environments, Leigh C. Latta Iv

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The hierarchy of biological organization, from molecules to ecosystems, describes the relationships among various biological systems. Of particular interest is assessing how the factors that primarily determine the nature of one hierarchical level also have transcendent qualities that affect the ecology and evolution of higher hierarchical levels. The goal of this dissertation was to use a bottom-up approach to examine the transcendent effects of two factors that strongly determine the nature of their associated level of biological organization. The first, phenotypic plasticity, is a primary factor that determines the phenotype of an individual. The second factor, genetic diversity, largely determines …

The Ability Of The Coping Competence Questionnaire To Predict Resilience Against Learned Helplessness Among Undergraduate College Students: An Experimental Study, Cindy L. Ollis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Coping Competence Questionnaire (CCQ), based on the reformulated learned helplessness theory, was designed to assess a general stress resistance versus a propensity towards learned helplessness with a brief, 12-item self-report questionnaire. In this study the CCQ was administered to 247 undergraduate students, who were then paired, in groups of around 24 at a time, and then randomly assigned to either success or failure conditions on the computer game TetraVex. Mood was pretested using the Profile of Mood States (POMS) depression subscale; the experimental condition, success or failure at TetraVex was conducted; then outcome measures including 20 five letter anagrams …

Development Of An Innovative Statewide Population Monitoring Program For Mule Deer, Heather H. Bernales

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Monitoring population trend and estimating vital demographic parameters are essential for effective management of a mule deer (Odocoileus hemionus) population. Because of financial constraints, many wildlife agencies use computer models to obtain indirect indices of population size and trend as an alternative to annual field-based estimates of population size. These models are based primarily on herd composition counts and harvest rates from hunter-harvest surveys, and are rarely field validated. I developed an alternative method for monitoring population dynamics of wintering populations of mule deer. I designed a hybrid monitoring program that combined annual vital rate monitoring to track changes in …

Changes In Hybrid Poplar Endophytic Microbial Diversity In Response To Trichloroethylene Exposure, Jared S. Ervin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Remediation of trichloroethylene (TCE) is a major priority for many contaminated sites all over the industrialized world including Hill Air Force Base, UT (HAFB). Phytoremediation as part of a cleanup strategy is an appealing option, and trees at HAFB have been studied to this end. Trees have also been used to delineate groundwater plumes because the passive uptake of organic contaminants by trees generally results in a direct relationship between tree and groundwater TCE concentrations if the trees are using the contaminated groundwater. However, the concentrations of plant-produced TCE metabolites can vary greatly. It was hypothesized that the endophytic microbial …

Transesterification And Recovery Of Intracellular Lipids Using A Single Step Reactive Extraction, Daniel R. Nelson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A single-step, extractive reaction for extraction of lipids such as biodiesel components, omega-3 fatty acids, or other triglycerides from microbial cells was examined. Conventional methods for lipid extraction use toxic solvents, and require multiple steps and long processing times. When the goal is to produce fatty acid methyl esters or FAMEs, the extracted lipids are subjected to a separate transesterification reaction with simple alcohols in the presence of an acid or base catalyst. A simplified, single-step reactive extraction method can be applied that combines the sequential extraction followed by transesterification using acidified alcohols - a process known as in situ …

Critique Of A Wildlife Habitat Evaluation Method Applied To Residential Open Space, Sarah Rigard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To this date, little research has been done evaluating the quality of wildlife habitat provided by open space in residential areas. Quality wildlife habitat for the purposes of this study is defined as those areas which contain the physical and biological characteristics necessary to support native wildlife species of the region. This thesis critiqued a wildlife habitat assessment method used in a nationwide study of residential open space for the purpose of better understanding the research conducted by the study and to inform similar, future habitat evaluations of landscapes altered by human activity to accommodate residential land use. The methodology …

Maternal Effects In Transmission Of Self-Medicative Behavior From Mother To Offspring In Sheep, Udita Sanga

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mammals begin learning food preferences in utero and maternally mediated influences early in life help offspring develop their feeding habits. Mammals also learn by individual experience to ingest medicinal compounds such as polyethylene glycol (PEG), which attenuates the negative post-ingestive effects of tannins, a group of potentially toxic plant secondary compounds. The objective of this study was to investigate the transmission of acquired self-medicative behavior from mother to offspring using polyethylene glycol (PEG) as a medicine to relieve malaise caused by tannins. I hypothesized that: 1) mothers trained to associate the beneficial effects of PEG while consuming tannins will pass …

Decentralized Coordination Of Multiple Autonomous Vehicles, Yongcan Cao

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation focuses on the study of decentralized coordination algorithms of multiple autonomous vehicles. Here, the term decentralized coordination is used to refer to the behavior that a group of vehicles reaches the desired group behavior via local interaction. Research is conducted towards designing and analyzing distributed coordination algorithms to achieve desired group behavior in the presence of none, one, and multiple group reference states.

Decentralized coordination in the absence of any group reference state is a very active research topic in the systems and controls society. We first focus on studying decentralized coordination problems for both single-integrator kinematics and …

Parents As Partners In Kindergarten And Second Grade Literacy Instruction: A Qualitative Inquiry Into Student-Authored Traveling Books, Dorothy C. Little

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this research was to study a sociocognitive “student/parent/peer authoring community” called Traveling Books (TBks) in kindergarten and second grade in a public elementary school setting. TBks are teacher-made vehicles for involving parents in peer-based literacy environments. The study was based on Epstein's theory that increasing overlap of students' spheres of influence, home, school, and community, creates a greater likelihood that children will learn what the parents want them to learn. The aim was to locate essential elements that triggered learning processes to occur and to discover research-based fundamentals still missing from TBks.

This qualitative inquiry incorporated the …

Genomic Perspectives On Evolution In Bracken Fern, Joshua P. Der

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The fern genus Pteridium comprises a number of closely related species distributed throughout the world. Collectively they are called bracken ferns and have historically been treated as a single species, Pteridium aquilinum. Bracken is notorious as a toxic weed that colonizes open fields and poisons livestock. Bracken is also easily cultured and has become one of the most intensively studied ferns. Bracken has been used as a model system for the study of the fern life cycle, fern gametophyte development, the pheromonal mechanism of sex determination, toxicology, invasion ecology, and climate change. This dissertation places bracken within a global …

Nutrient Utilization From Anaerobic Digester Effluent Through Algae Cultivation, Shantanu Wahal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nutrients present in digested animal waste can be utilized for algae cultivation under suitable conditions. Algal growth, however, depends on the chemical forms and speciation of these nutrients. In this study a chemical equilibrium model was first used to describe nutrient speciation and predict conditions that enhance the solubility of nutrients in anaerobic digester effluent. Dilution with water and separation of large particulates greatly improved nutrient availability and light penetration - conditions favorable for algal cultivation. Algae growth was tested using three strains - Scenedesmus dimorphous (UTEX # 417), Chlorella vulgaris (UTEX# 265), and an algal isolate (designated as LLAI …

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 …