Digital Commons Network^™

Neural Networks And The Natural Gradient, Michael R. Bastian

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Neural network training algorithms have always suffered from the problem of local minima. The advent of natural gradient algorithms promised to overcome this shortcoming by finding better local minima. However, they require additional training parameters and computational overhead. By using a new formulation for the natural gradient, an algorithm is described that uses less memory and processing time than previous algorithms with comparable performance.

Comparison Of Agricultural Area Source Ammonia Gas Concentration And Flux Measurements, Emyrei Reese

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was conducted in order to compare and evaluate a variety of ammonia (NH₃) measurement techniques for determination of ambient gas phase concentration and evaluation of system fluxes. This was accomplished by measuring NH3 emitted from area sources within two dairies, one located in south-central Idaho and another in central California. The measurement techniques utilized included: an array of passive diffusion samplers, a single annular denuder system, a single or paired Fourier transform infrared spectrometer(s) (FTIR), a paired (upwind and downwind) set of differential optical absorption spectrometers (DOAS), and a portable wind tunnel in conjunction with a …

Drivers Of Plant Population Dynamics In Three Arid To Subhumid Ecosystems, Luke J. Zachmann

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding the relative importance of density-dependent and density-independent factors in driving population dynamics is one of the oldest challenges in ecology, and may play a critical role in predicting the effects of climate change on populations. We used long-term observational data to describe patterns in plant population regulation for 57 forb and grass species from three different ecosystems (arid desert grassland, semiarid sagebrush steppe, and subhumid mixed-grass prairie). Using a hierarchical partitioning approach, we (i) quantified the relative influence of conspecific density, heterospecific composition, and climate on temporal variation in population growth rates, and (ii) asked how the relative importance …

Investigation Of The Toxicity And Toxicokinetics Of Selenium From The Accumulator Plant Symphyotrichum Spathulatum (Western Mountain Aster) In Sheep, Amanda Wilhelm

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was designed to observe the effects of selenium from plant material in sheep after a single, oral dose. Purified sodium selenite and selenomethionine were given as positive controls. The plant Symphyotrichum spathulatum (Western Mountain Aster) was collected, analyzed for selenium content, and administered orally to sheep at varying doses according to body weight. Clinical signs were observed for 7 days during which time whole blood, serum, and expired air were collected. Following euthanasia, tissues were collected for histopathological analysis and mineral analysis.

Clinical signs were less apparent than expected and included depression and mild dyspnea in sheep receiving …

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 …

Introduced Sport Fish And Fish Conservation In A Novel Food Web: Evidence Of Predatory Impact, Kevin Lee Landom

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study addressed a fundamental question in applied ecology and conservation; what is the predatory impact of introduced piscivorous sport fish on imperiled native fish populations? More specifically, which of many introduced species and size-classes represent the greatest threats and should be targeted for control? In order to explore this important question, an integrated analysis of stable isotopes, quantified observed diet analysis, and stable isotope mass-balance models were used to quantify trophic interactions. These tools were used to construct food web models that were then compared to draw inferences regarding the relative contribution of prey fish, including rare native fish, …

Learning Ability And Factors Influencing Nest Establishment Of The Solitary Bees Osmia Lignaria And Megachile Rotundata (Hymenoptera: Megachilidae), Cory A. Vorel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Over the last several decades, the use of solitary bees as an alternative to honey bees (Apis mellifera L.) for pollination of commercial crops has increased, in part as a response to ongoing problems faced by commercial honey bee populations. Two solitary bee species have exhibited great commercial potential: the blue orchard bee, Osmia lignaria Say, and the alfalfa leafcutting bee, Megachile rotundata Fabricius (Hymenoptera: Megachilidae). However, growth of O. lignaria and M. rotundata populations is limited in commercial systems, mainly due to low establishment of females at provided nesting sites, possibly due to mortality, dispersal, or other causes. …

Finding, Nurturing, And Instilling Hope In Family Therapy, Joseph Daniel Tschudy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The development of a personal theory of therapy and change is an integral part of the training and educational philosophies of the Marriage and Family Therapy Program at Utah State University. This personal theory attempts to identify and explain each student's beliefs regarding the specific mechanisms by which change occurs, thus providing a therapeutic backbone from which one may integrate various interventions, ideas, concepts, and approaches to therapy. As one engages in the process of integration, it becomes critical for students to evaluate their performances. A thorough self-evaluation that includes the utilization of scientific methods leads to the development of …

The Ecological Influences Of Community Trail Use And Physical Activity Among Female Trail Users, Sarah N. Moulton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Despite great effort to improve physical activity, little success has come to pass. Due to this, some researchers have shifted from individual approaches to promoting physical activity to multilevel environmental approaches. One of these multifaceted environmental approaches is through community trails. A small body of research has suggested that community trails may be a successful ecological approach to promoting physical activity. However, the research is minimal and inconsistent in supporting effectiveness of community trails for promoting physical activity.

This study sought to examine ecological factors to learn if and how they might influence trail use among women. The ecological factors …

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 …

Intercomparison Of Prism And Daymet Temperature Interpolation From 1980 To 2003, Rebecca A. Scully

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As ecosystem modeling becomes increasingly integrated with Geographic Information Systems (GIS) there is a rise in demand for spatially and temporally continuous meteorological data. But in order to justify management decisions or to provide robust scientific insights, the accuracy of meteorological data used as model input must be thoroughly quantified. Current methods to create spatially continuous climate data from discrete weather station data include inverse distance weighting, geostatistical techniques such as kriging and splines, local regression models such as Parameter-Elevation Regression on Independent Slope Model (PRISM) and Daymet, and regional regression models. For the conterminous United States, PRISM and Daymet …

Snowshoe Hare And Forest Structure Relationships In Western Wyoming, Nathan Daniel Berg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Snowshoe hares (Lepus americanus) are a critically important prey species for Canada lynx (Lynx canadensis). Determination of snowshoe hare distribution and abundance is needed in western Wyoming for lynx conservation. We used linear regression to examine the correlations between snowshoe hare density, as determined by mark-recapture estimates, and fecal pellet plot counts on both uncleared and annually cleared plots on the Bridger-Teton National Forest, western Wyoming. We found significant correlations between hare density estimates and fecal pellet counts for both uncleared and annually cleared pellet counts; however the relationship was much stronger for annually cleared pellet …

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 …

Development Of A Laboratory Based System For Selecting Insect Pathogenic Fungi With Greatest Potential For Success In The Field, Chad Alton Keyser

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Many insects are important agricultural pests, and active control is necessary to keep them at abeyance. The naturally occurring entomopathogenic fungus Metarhizium is a promising tool to control pest insects, and its use avoids the well-known harmful side effects of chemical pesticides. Thousands of unique isolates of Metarhizium exist throughout the world. These isolates vary widely in their ability to cause infection and to tolerate stressful habitats. The research reported here tests the THESIS: A laboratory-based system can be devised that identifies, from among many Metarhizium isolates, those isolates with the greatest potential for successful biological control of pest insects …

Quantifying Legacy Effects Of Managed Disturbance On Sagebrush Steppe Resilience And Diversity, Julie Ripplinger

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Land-use legacies can affect landscapes for decades to millennia. A long history of shrub management exists in the sagebrush steppe of the Intermountain West where shrub-removal treatments, a type of managed disturbance, have been implemented for over 50 years to reduce sagebrush cover. The assumption behind managed disturbances is that they will increase forage for domestic livestock and improve wildlife habitat. However, the long-term effects of managed disturbance on plant community composition and diversity are not well understood. We investigated the legacy effects of three common types of managed disturbance (chemical, fire, and mechanical treatments) on plant community diversity and …

Development Of Novel Methods And Their Utilization In The Analysis Of The Effect Of The N-Terminus Of Human Protein Arginine Methyltransferase 1 Variant 1 On Enzymatic Activity, Protein-Protein Interactions, And Substrate Specificity, Brenda Bienka Suh-Lailam

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Protein arginine methyltransferases (PRMTs) are enzymes that catalyze the methylation of protein arginine residues, resulting in the formation of monomethylarginine, and/or asymmetric or symmetric dimethylarginines. Although understanding of the PRMTs has grown rapidly over the last few years, several challenges still remain in the PRMT field. Here, we describe the development of two techniques that will be very useful in investigating PRMT regulation, small molecule inhibition, oligomerization, protein-protein interaction, and substrate specificity, which will ultimately lead to the advancement of the PRMT field. Studies have shown that having an N-terminal tag can influence enzyme activity and substrate specificity. The first …

Effects Of Corn Silage Hybrids And Dietary Nonforage Fiber Sources On Productive Performance In Early Lactating Dairy Cows Fed High Forage Diets, Michael Shane Holt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This experiment was conducted to determine the effects of corn silage hybrids and nonforage fiber sources (NFFS) in high forage diets formulated with high dietary proportion of alfalfa hay (AH) and corn silage (CS) on ruminal fermentation and productive performance by early lactating dairy cows. Eight multiparous Holstein cows (4 ruminally fistulated) averaging 36 ± 6.2 d in milk were used in a duplicated 4 × 4 Latin square design experiment with a 2 × 2 factorial arrangement of treatments. Cows were fed 1 of 4 dietary treatments during each of the four 21-d periods. Treatments were: 1) conventional corn …

Our Mountain Home: The Oscar And Emma Swett Ranch, Carolyn Toone

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In this thesis, I examined the lives of my great-grandparents, Oscar and Emma Swett. Oscar began a homestead in the Uinta Mountains in 1909, which he successfully ran for nearly sixty years. My grandmother was born on the ranch, and my own father spent much of his time there. I look at how land policy changed from encouraging ranching and farming in the early 1900's to tourism and recreation in the 1960's, with the coming of the Flaming Gorge Dam. The lives of my great-grandparents and their children were shaped by these changes and they felt the consequences of the …

Coyote Diet And Movements In Relation To Winter Recreation In Northwestern Wyoming: Implications For Lynx Conservation, Jennifer L. Burghardt Dowd

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Increased snowmobile use in mountainous terrain has been highlighted as a conservation concern for some Canada lynx (Lynx canadensis) populations. Snow compaction resulting from winter recreation may potentially facilitate access by coyotes (Canis latrans) to habitats used by lynx during winter. Increased interactions could result in either exploitation or interference competition between the two species. Two recent, yet geographically distinct, studies showed contrasting findings regarding coyote movements and their use of snow-compacted trails during the winter. These findings suggest coyote association with snow-compacted trails may be regionally specific and dependent upon ecosystem dynamics and snow characteristics. …

"To Drink From Places": Uncovering A Rich Way Of Life Near The Grand Canyon's North Rim, Melinda Snow Rich

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The chapters of this thesis focus on the history and stories of the people who built and traveled down the highways--Highway 89A, Highway 89, and Highway 67--that branch out from the junction in front of Jacob Lake Inn, the Bowman/Rich family's 87-year-old lodge. The family's role in building roads, supporting and encouraging the growing tourist industry in Kanab and the North Rim of the Grand Canyon, and the converging effects of these choices have created the unique family culture and contributed to the history of the Grand Canyon region over time. Ultimately this thesis is about relationships, about the connections, …

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 …

History Steps Off The Page: The Past In The Future, A Case Study Of How The Mormon Battalion Is Making History Interactive, Allyson Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis addresses the presentation of the Mormon Battalion's history in three interactive forms. The Battalion served in the U.S.-Mexican War between 1846 and 1847. In 2008 a group known as Battalion Trek chose to rehike the original trail as closely as possible. The three chapters of this thesis address the reenactors who planned and completed the rehike, the blog they kept as they did so, and a program which allows those interested to learn more about the trail. Analyzing what such presentations have to offer is important as history moves into the hands of the public and as the …

The Effects Of Pedagogical Agents On Mathematics Anxiety And Mathematics Learning, Quan Wei

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to investigate the impact of the mathematics anxiety treatment messages in a computer-based environment on ninth-grade students' mathematics anxiety and mathematics learning. The study also examined whether the impact of the treatment messages would be differentiated by learner's gender and by learner's prior mathematics anxiety levels (High vs. Medium vs. Low). Participants were 161 ninth-grade students, who took a required introductory algebra class in a public high school neighboring Utah State University. The learning environment was integrated with a pedagogical agent (animated human-like character) as a tutor. This study employed a pretest and posttest …

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 …