Digital Commons Network^™

Ungulate Damage To Safflower In San Juan County, Utah, Michael J. Haney

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In Utah, farmers are concerned that ungulates are damaging safflower (Carthamus tinctorius) fields. I examined elk (Cervus elaphus) and mule deer (Odocoileus hemionus) damage to safflower production in San Juan County, Utah during 2009 and 2010. Data on damaged safflower plants were collected within 28 fields, totaling 1,581 ha (13 fields totaling 963 ha during 2009; 15 fields totaling 618 ha during 2010). I compared 3 methods to assess losses: ungulate-proof exclosures, adjacent plant compensation method, and counting the number of damaged plants in 50-m transects (safflower count method). Exclosures were of limited use …

Reducing Reliance On Supplemental Winter Feeding In Elk (Cervus Canadensis): An Applied Management Experiment At Deseret Land And Livestock Ranch, Utah, Dax L. Mangus

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wildlife managers have fed elk in North America for nearly 100 years. Giving winter feed to elk can compensate for a shortage of natural winter range and may boost elk populations while also helping prevent commingling with livestock and depredation of winter feed intended for livestock. In contrast to these benefits of supplemental feeding, there are economic and environmental costs associated with feeding, and elk herds that winter on feeding grounds have a higher risk of contracting and transmitting disease. Brucellosis is of primary concern now, and Chronic Wasting Disease may be in the future. Many see the discontinuation of …

Ecology And Conservation Of Cougars In The Eastern Great Basin: Effects Of Urbanization, Habitat Fragmentation, And Exploitation, David C. Stoner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research was designed to investigate cougar response to urbanization, habitat fragmentation, and exploitation from behavioral, demographic, and landscape perspectives. The source-sink model has been proposed as an alternative framework for the management of exploited cougar populations. I addressed the basic question of whether cougars conform behaviorally to the predictions of the source-sink model, and consequently, the applied question of whether the model could be used for the conservation of this species. To achieve this I evaluated three scale-specific questions using radio-telemetry and hunter-harvest data collected from 1996-2010. At the subpopulation scale, I tested the hypothesis that cougars are wildland …

Examining The Effects Of Reinforcement Context On Relapse Of Observing, Eric A. Thrailkill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Attentional biases occur with various psychological disorders, including drug addiction and anxiety. Conditioned reinforcement likely plays a role in maintaining attentional biases to stimuli associated with reinforcement for unwanted behavior. The observing-response procedure is considered a model of attending as reflected by responding maintained by conditioned reinforcement. Effects of primary reinforcement on the persistence of observing have been studied in the framework of behavioral momentum theory. Studies have shown observing-responses to be more resistant to
change in contexts arranging relatively higher rates of primary reinforcement. Recently, behavioral momentum theory has been extended to describe the effects of primary reinforcement context …

An Evaluation Of State-And-Transition Model Development For Ecological Sites In Northern Utah, Jamin K. Johanson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ecological sites and state-transition models (STMs) have become the preferred means of summarizing plant community dynamics on distinctive types of rangeland. Ecological sites classify rangeland types based on soil-geomorphic and climatic conditions capable of producing a known plant community, while a STM depicts the vegetation dynamics of an ecological site. STMs are usually based on expert opinion rather than site-specific data; however, if they are to gain credibility, STMs must accurately describe the processes that drive plant community dynamics. This study examined three ways of developing process-based STMs using three levels of commonly collected field data. We began by taking …

Investigating The Strategies To Improve The Quality Of Low-Fat Mozzarella And Cheddar Cheeses, Ranjeeta Wadhwani

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ranjeeta Wadhwani in supervision of Dr. D. J. McMahon, has worked on investigating the various strategies to improve three qualities of low-fat cheeses. These three qualities were meltability, color, or feasibilities to incorporate dietary fiber into the low-fat cheese with its simultaneous effect on texture. There has been an ongoing research on improving the quality of low-fat cheese. In our study, low-fat Mozzarella cheese curds of 4 different fat content (1.5, 3.0, 4.5, and 6.0%) were comminuted and externally added with melted butter in the amount to get 6% fat in final cheese for low-fat claim. Addition of melted butter …

Effect Of Heavy Metals Found In Flue Gas On Growth And Lipid Accumulation For Green Algae Scenedesmus Obliquus, Reece Butler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In recent years there has been a growing interest within the United States to replace fossil fuels with biofuels for environmental and national security reasons. Algal feedstocks have the potential of producing significantly higher yields of oil for biofuels than any other source. It is well known that high concentrations of CO₂ can increase algal yields. Flue gas from coal fire power plants is an obvious source of CO₂. The flue gas, however, will contain other chemicals besides CO₂ that may not be beneficial to the algae. The research objectives for this study were to determine …

Exploring The Relationship Between Place Identity And Personalization Of Space In Temporary Student Housing, Joshua H. Rowley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study is to better understand the relationship between the personalization of one’s physical environment and the degree of place identity the person has toward their space, specifically those living in temporary student housing. There have been several studies on peoples’ inherent need to personalize their space. While previous research has identified key factors that help to define place identity in general, this study addresses the fact that not much has been said about how people in temporary housing, specifically student housing, actually go about creating their living spaces.

The key issues this research addressed were the …

Prize-Based Contingency Management: A Vehicle Miles Of Travel Reduction Intervention, Joshua D. Marquit

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During the past 50 years, air pollution has become a growing problem throughout the Intermountain West because of increases in personal vehicle ownership and usage. Scientists continue to design interventions to improve air quality by encouraging people to reduce their personal vehicle miles of travel (VMT). However, results of these interventions have only seen modest reductions in VMT because of some methodological and measurement issues. To address these limitations, a 14-week driving reduction intervention was conducted in Cache County, Utah. This intervention employed a prizebased contingency management system within a single-subject, A-B-A withdrawal research design that rewarded participants with prizes …

Global 4-H Network: Laying The Groundwork Survey, Jennifer Major

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A descriptive study examining 4-H programs in Africa, Asia, and Europe was conducted for the National 4-H Council. Program size, scope, structure, organization, and funding varied greatly by country and few of the programs were connected to a university, but many partnered with other 4-H organizations around the world. Program participants were found to be primarily male with few programs specifically for women. A list of content areas provided by the 4-H programs was also obtained and compared to top agricultural commodities in their country. Very few content areas offered by the country aligned with their major agricultural commodities even …

Quantitative Genetic Analysis Of Reproduction Traits In Ball Pythons, Benson H. Morrill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Although the captive reproduction of non-avian reptiles has increased steadily since the 1970’s, a dearth of information exists on successful management practices for large captive populations of these species. The data reported here come from a captive population of ball pythons (Python regius) maintained by a commercial breeding company, The Snake Keeper, Inc. (Spanish Fork, UT). Reproductive data are available for 6,480 eggs from 937 ball python clutches. The data presented suggest that proper management practices should include the use of palpation and/or ultrasound to ensure breeding occurs during the proper time of the female reproductive cycle, and …

Evaluating The Effects Of Reinforcer Choice And Reinforcer Variation On The Response Rates Of Children With Autism, Alice Ann Keyl Austin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Motivating individuals with autism can be challenging for clinicians and educators seeking to increase skills or decrease problem behaviors. Even when highly preferred reinforcers have been identified, they tend to lose their effectiveness over time. Over the years, several strategies have been developed to maintain the effectiveness of reinforcers. Reinforcer variation has been demonstrated to attenuate decreases in responding associated with repeated exposure to a single reinforcer. Another strategy that has been used to help maintain responding is allowing an individual a choice among reinforcers. Several researchers have suggested that providing choice among several reinforcers may produce the same effects …

Process-Based Management Of Downy Brome In Salt Desert Shrublands: Assessing Pre- And Post- Rehabilitation Soil And Vegetation Attributes, Merilynn Carol Hirsch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As an ecosystem driver, downy brome (Bromus tectorum L.) presents obstacles to land rehabilitation efforts, including restoring desirable species cover. Because damaged ecosystems may have crossed both abiotic and biotic thresholds, ecologically-based control strategies may assist with altering successional trajectories and restoring desirable plant species. My thesis research had three objectives: 1) assess soil and vegetation relationships in degraded salt desert ecosystems prior to implementing downy brome control treatments, 2) determine the effects of control treatments on soil properties and resident plant species, and 3) evaluate the relative importance of shrubland soil type, herbicide type, and herbicide rate on seedling …

Causes, Extent, And Consequences Of Lead-Pellet Ingestion By Chukars (Alectoris Chukar) In Western Utah: Examining Habitat, Search Images, And Toxicology, R. Justin Bingham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lead ingestion adversely affects humans and over 130 species of wildlife. Wild chukars (Alectoris chukar) are documented to ingest lead, but the causes and consequences of this ingestion are poorly understood. The objectives of this research were to 1) examine the influence of habitat use, the hunting season, and seasonal climate on the extent and severity of lead ingestion by chukars in western Utah, 2) assess the effects of habitat use, feeding behaviors, and lead density on the causes of lead-pellet ingestion in captive and wild chukars, and 3) investigate the consequences of lead-pellet ingestion in captive chukars as a …

Temperature Increase Effects On Sagebrush Ecosystem Forbs: Experimental Evidence And Range Manager Perspectives, Hilary Louise Whitcomb

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sagebrush plant communities are among the most threatened in North America. This project had two goals: to test how increased temperature affects native and nonnative forb species common to the Western sagebrush region and to evaluate land manager beliefs about changes in their ecosystems, including those affecting forb species.

Native forbs Sphaeralcea munroana, Crepis acuminata, Linum lewisii, Penstemon palmeri, and Oenothera pallida and non-natives Erodium cicutarium and Lactuca serriola were each subjected to two treatments: experimental warming using open-top chambers and a control. Knowing how forbs used in restoration might respond to future conditions is both …

Microbiological, Thermal Inactivation, And Sensory Characteristics Of Beef Eye-Of-Round Subprimals And Steaks Processed With High-Pressure Needleless Injection, Laura Kahealani Jefferies

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

High-pressure needleless injection (HPNI) is a process where small-diameter, high-velocity burst of liquid, penetrate foods at pressures ≤ 10,000 psi. The potential of HPNI as an enhancing technique for meat was studied. In study 1, HPNI translocated surface E. coli O157 into the interior of beef eye-of-round subprimals with an incidence of 40 (±7), 25 (±8), and 25 (±8)% for meat that had been surface-inoculated with a four-strain cocktail at 0.5, 1, and 2 log₁₀ CFU/cm², respectively. Run-off water contained 2, 2, and 3 log₁₀ CFU/ml and was used for HPNI of additional subprimals, which resulted …

Establishing Weed Prevention Areas And Evaluating Their Impact, Stephanie Christensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The spread of invasive weeds continues to be a serious economic and environmental threat. Weed prevention has the potential to stop weeds before they become well established in an area conserving time, energy, and resources. Unfortunately, weed prevention is often overlooked. Weed Prevention Areas (WPAs) are a relatively new tool developed to help improve the application of weed prevention. They are cooperatively managed areas that focus on implementing prevention and early detection strategies at a community level. The purpose of this research was to establish baseline data that will be used to evaluate the overall effectiveness of the WPA concept, …

Nondrug Reinforcement Loss And Relapse To Alcohol Seeking In Another Context, Adam D. Pyszczynski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Extinguished alcohol-maintained responding has been shown to relapse in a
resurgence preparation when food-reinforced responding is subsequently extinguished within the same context. However, drug and nondrug reinforcers are often specific to different contexts. Accordingly, the present experiments sought to determine whether loss of an alternative source of nondrug reinforcement in one context could produce relapse to drug seeking in a separate context. In one experiment, rats made topographically different responses for food or alcohol in alternating components of a multiple schedule. Both reinforcers were delivered during baseline, alcohol was withheld during the second phase of the experiment, and finally both …

Stratigraphic, Microfossil, And Geochemical Analysis Of The Neoproterozoic Uinta Mountain Group, Utah: Evidence For A Eutrophication Event?, Dawn Schmidli Hayes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Several previous Neoproterozoic microfossil diversity studies yield evidence for a relatively sudden biotic change prior to the first well‐constrained Sturtian glaciations. In an event interpreted as a mass extinction of eukaryotic phytoplankton followed by bacterial dominance, diverse assemblages of complex acritarchs are replaced by more uniform assemblages consisting of simple leiosphaerid acritarchs and bacteria. Recent data from the Chuar Group of the Grand Canyon (770‐742 Ma) suggest this biotic change was caused by eutrophication rather than the direct effects of Sturtian glaciation; evidence includes total organic carbon increases indicative of increasing primary productivity followed by iron speciation values that suggest …

Testing The Efficacy Of Merrill’S First Principles Of Instruction In Improving Student Performance In Introductory Biology Courses, Joel Lee Gardner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

One learning problem is that public understanding of science is limited. Many people blame at least part of the problem on the predominant lecture approach for students' lack of science understanding. Current research indicates that more active instructional approaches can improve student learning in introductory undergraduate biology courses. Active learning may be difficult to implement because methods and strategies, ranging from in-class collaborative problem-solving to out of class multimedia presentations, are diverse, and sometimes difficult to implement. Merrill's First Principles of Instruction (hereafter referred to as "First Principles" or "First Principles of Instruction") provides a framework for implementing active learning …

Comparative Studies On Scale-Up Methods Of Single-Use Bioreactors, Emily B. Stoker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was performed to increase knowledge of oxygen mass transfer (kLa) and mixing times in the scale-up of disposable bioreactors.Results of oxygen mass transfer studies showed kLa to increase with increasing agitation and aeration rates. By maintaining a scale-up constant such as gassed power to volume or shear, an almost constant k_La was achieved during scale-up from 50 to 2000 L. Using the scale-up constant P_g/V resulted in statistically higher kLa values at greater reactor volumes. Mixing times were revealed to be significantly affected by agitation, but not by the aeration rates tested. No pattern …

Understanding Teacher Users Of A Digital Library Service: A Clustering Approach, Beijie Xu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research examined teachers' online behaviors while using a digital library service—the Instructional Architect (IA)—through three consecutive studies. In the first two studies, a statistical model called latent class analysis (LCA) was applied to cluster different groups of IA teachers according to their diverse online behaviors. The third study further examined relationships between teachers' demographic characteristics and their usage patterns. Several user clusters emerged from the LCA results of Study I. These clusters were named isolated islanders, lukewarm teachers, goal-oriented brokers, window shoppers, key brokers, beneficiaries, classroom practitioners, and dedicated sticky users. …

Determining Profitability Strategies For Various Retained Ownership Enterprises In Utah, Matthew H. Hirschi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

With the price of corn now over $6 per bushel, and with feedlot total cost per pound of gain now approaching $1.00 per pound of gain there are new incentives to try and add weight to calves outside of feedlots. The question then arises of how to add weight to a calf in the most economical manner. There are many different feeding programs to consider. However, with few exceptions, the cheapest way to add weight outside of a feedlot usually involves the calf grazing for an extended period of time. Winter pasture grazing, wheat pasture grazing and corn stalk grazing …

Graphshop: An Interactive Software Environment For Graph Theory Research And Applications, Aaron Andersen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Graph Theory is the mathematical study of the structure of abstract relationships between objects. Although these constructions (graphs) are themselves purely theoretical, their ability to model pair-wise relationships in systems of arbitrary complexity yields abundant direct correspondence with numerous important physical and societal systems in the real world. Additionally, the simple discrete nature of fundamental graph structures allows for easy pseudo-geometric visualization of graphs in a wide variety of ways. Taken together, these two properties suggest that graph theory teaching, research, and applications would benefit greatly from the use of a unified software environment for graph construction, interaction, and visualization. …

Stress Response And Pathogenesis Of Salmonella Enterica Serovar Typhimurium, Jigna D. Shah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Salmonella is a food-borne pathogen that leads to substantial illness worldwide. The clinical syndromes associated with Salmonella infection are enteric (typhoid) fever and gastroenteritis, in healthy humans. Typhoid fever is caused by host-adapted S. Typhi and S. Paratyphi. Gastroenteritis is caused by serovars usually referred to as non typhoidal Salmonellae (NTS). In recent years, an increasing number of outbreaks due to NTS, despite increased efforts in food safety, were reported because of persistence of Salmonella in the food chain. Thus I hypothesized that Salmonella is able to withstand stresses in the environment and treatments used during food processing …

Individualistic Response Of Piñon And Juniper Tree Species Distributions To Climate Change In North America's Arid Interior West, Jacob R. Gibson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Piñon and juniper tree species have species-specific climatic requirements, resulting in unique distributions and differential responses to climate change. Piñons and junipers co-dominate the arid woodlands of North America as groups with widespread hybridization. Two piñons, Pinus edulis; P. monophylla, and four junipers, Juniperus deppeana var. deppeana; J. monosperma; J. occidentalis; J. osteosperma, are endemic to the midlatitude interior west and form three groups of hybridizing sister species, P. edulis-P. monophylla; J. deppeana var. deppeana-J. monosperma; J. occidentalis-J. osteosperma. Recent droughts have caused widespread mortality among piñons, but have had less impact on …

Behavioral Responses Of Willow Flycatchers, Empidonax Traillii, To A Heterogeneous Environment, Amanda V. Bakian

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spatial heterogeneity impacts population and community-level dynamics including species-level dispersal patterns, the use and availability of refugia, predator/prey dynamics, and reproductive fitness. Understanding how wild animal populations respond to environmental heterogeneity is essential for their proper management and conservation. In this study, I examine the responses of Willow Flycatchers to spatial heterogeneity in the distribution of their food and habitat resources. Over the course of three breeding seasons, I radio- tracked Willow Flycatchers at Fish Creek in Manti-La Sal National Forest in Utah, recorded detailed behavior data at each radio location, and collected fecal, feather and insect samples. I formulated …

Development Of A Beef Flavor Lexicon And Its Application To Compare Flavor Profiles And Consumer Acceptance Of Grain- And Pasture-Finished Cattle, Curtis A.J. Maughan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Flavor lexicons are used in sensory evaluation to determine the flavor profile of a food product. The objective of this study was to develop a flavor lexicon for cooked beef, which can then be used in various projects relating to beef quality such as studies investigating animal diet, marinating, ageing, or other enhancements. A descriptive panel of 10 people was used to develop a flavor lexicon of 18 attributes, including astringent, barny, bloody, brothy, browned, gamey, grassy, juicy, fatty, livery, metallic, oxidized, roast beef, and the five basic tastes (bitter, salty, sour, sweet, and umami). In contrast to other studies …

Three Essays On The Economic Impact Of Bovine Spongiform Encephalopathy In The United States, Rachna Gollamudi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The first native-born case of Bovine Spongiform Encephalopathy (BSE or commonly known as Mad Cow Disease) in North American continent was reported on 20 May 2003 in central Alberta, Canada. The first case of BSE in the United States was announced on 23 December 2003.

My dissertation is divided into three essays on the economic impact of the outbreak of Bovine Spongiform Encephalopathy (BSE) in the United States in December 2003. The first essay focuses on quantifying the impact of the outbreak of BSE in the United States and Canada on the stock returns of major publicly traded agribusiness firms …

Habitat Characteristics And Occupancy Rates Of Lewis's Woodpecker In Aspen, Amy M. Vande Voort

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lewis‘ woodpeckers (Melanerpes lewis) are generally associated with open ponderosa pine (Pinus ponderosa), open riparian, and burned pine habitats in the West; however, this species has recently been found to nest in aspen (Populus tremuloides) stands in Utah. This study describes the habitat characteristics of Lewis‘ woodpecker nest sites in aspen and investigates how well aspen stand characteristics predict Lewis‘ woodpecker occupancy. I surveyed for Lewis‘ woodpeckers at previously occupied nesting locations in aspen and took habitat measurements at nest sites. In addition, nest-centered Forest Inventory and Analysis (FIA)-type plots provided stand-level habitat characteristics. I used logistic regression to …