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Biogeography, Population Genetics, And Community Structure Of North American Bumble Bees, Jonathan Berenguer Koch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In 2011, several wild North American bumble bee pollinator species were reported to have declined by up to 96% in relative abundance in comparison to historic estimates, and one species was speculated to be extinct. None of these species have yet been documented to have recovered from these declines and additional species are now suggested to be at risk. Imperiled species in particular show increased specificity to narrow climatic envelopes, as opposed to putatively stable species. My dissertation describes patterns of population genetic diversity, structure, and gene flow pathways associated with climate variation and historical biogeography of bumble bees distributed …

The Effects Of Social Norms Feedback On Fruit And Vegetable Consumption And Skin Carotenoids Among College Students, Troy A. Bailey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fruit and vegetable consumption, which has been shown to have a protective effect against chronic diseases, often decreases during the first few years of college. Implementing public health interventions to improve consumption of these foods may be time-consuming, costly and burdensome. The aim of this study was to determine if a social norms intervention, examining the effects of normative and manipulated feedback of participants’ carotenoid scores compared to a no-norm control, could increase fruit and vegetable consumption among college students. Such a strategy could be a cost-effective method for promoting healthy diets in this population.

While self-reported increases in fruit …

Young Widows' Grief: A Descriptive Study Of Personal And Contextual Factors Associated With Conjugal Loss, C. Ryan Dunn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Grief is a natural condition resulting from the death of a loved one, and one of the most grievous experiences a person can endure is the death of a spouse. Grief can be influenced by relationships, the setting, and the survivor’s personal and social resources. Despite many studies on widowhood, young widows have received little attention. This study of 232 young widows between the ages of 18 and 55 in their first 5 years following loss was done to better describe the personal and social factors associated with younger widows’ grief. An online survey was distributed through social network sites …

College Student Perceptions Of Secondary Teacher Influence On The Development Of Mathematical Identity, Kathryn Van Wagoner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Through interviews with college students, this qualitative study explored how the students' experiences with their secondary mathematics teachers affected their relationship with mathematics, known as mathematical identity. The study was rooted in the idea that learning is an experience of identity and in John Dewey's theory that all experiences are inextricably linked to past and future experiences. The eight college students' interview responses were written into biographical narratives and then analyzed within preselected themes related to experiences with secondary teachers and dimensions of mathematical identity. These themes were determined through a review of previously published studies on those topics.

The …

Gorongosa: A History Of An African Landscape, 1921-2014, Domingos João Muala

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Gorongosa: a history of African landscape, 1921-2014, focuses on changes in the Gorongosa ecosystem, in central Mozambique, southeastern Africa. Environmental changes result from natural, non-human causes and from the activities of humans. I describe four socioecological events: African and Portuguese interactions, Gorongosa National Park, the effects of Mozambique's civil war, and the Park's restoration in the aftermath of the civil war. Prior to European partition of Africa in 1884-85, Mozambique did not exist as clearly a demarcated territory as it is now. Today, the sense of Mozambicanhood bears traces of Portuguese colonial era experience. The demarcation of Mozambique's boundaries and …

Development Of Genetic Goat And Hamster Models Of Atrial Fibrillation And Long Qt Syndrome; And Genetic Hamster Models Of Middle East Respiratory Syndrome, Dane A. Rasmussen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Atrial fibrillation (AF) and long QT syndrome (LQTS) are potentially lethal heart rhythm disorders that can be caused by mutations in the potassium channel gene KCNQ1. Middle East Respiratory Syndrome (MERS) is a viral infection with the potential to replicate the devastating effects of the SARS outbreak in 2003. All three of these diseases are in need of genetic animal models.

To address these needs, my thesis project focused on the development of genetic goat and hamster models of AF and LQTS, and genetic hamster models of MERS. Because of the goat’s similar organ size/physiology and the hamster’s similar lipid …

Ego-Identity And Long-Term Moratoria: Associations With College Attendance And Religious Volunteerism, Mark A. Jackson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objective of this study was to examine the extent to which college experiences and participation in religious missionary service for an extended period were associated with ego-identity development, specifically in terms of identity exploration and commitment. A sample of late adolescents (N = 425), all of whom had participated in at least some college and of whom 122 had volunteered as LDS missionaries, provided information about their college/missionary experiences that could be related to identity development and reported levels of identity exploration and commitment.

Results indicated that LDS postmissionaries and LDS non-postmissionaries differed significantly only in the variables …

Scalable Bio-Production Of High Value Products In Bacteria, Yukie Kawasaki

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Natural products are structurally and chemically diverse bioactive compounds produced by living organisms. The complex structures of natural products are often difficult to duplicate synthetically and thus industrial production of natural products most often depends on use of the host organisms. In this dissertation research, scalable production of natural products was pursued in bacterial platforms.

Biliverdin IXα is a natural anti-inflammatory compound which is emerging as a potent cytoprotectant in the medical field. Syringomycin E is a natural fungicide expected to be an effective agrofungicide in organic farming. Both biliverdin IXα and syringomycin E have limited supplies in the market. …

Novel Techniques To Determine Soil Evaporation Rates: Heat Pulse Probe And Automated Microlysimeter, Kashifa Rumana

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Increase in world population rate has augmented the global water use in municipal, industrial, and agricultural sectors, with renewable water resources changing
very little with time. Climate change and variability, degradation of water quality as a result of industrial waste streams, animal manure and waste, application of chemicals, pesticides, pharmaceuticals, heavy metals, etc. have largely influenced the quantity and quality of soil water. Root zone water helps sustain the agricultural industry by providing much of the water needed for irrigation. It is critical to monitor the soil water availability, especially within the plant root zones. The subsurface water tends to …

Direct Electrical Arc Ignition Of Hybrid Rocket Motors, Michael I. Judson Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Hybrid rockets motors provide distinct safety advantages when compared to traditional liquid or solid propellant systems, due to the inherent stability and relative inertness of the propellants prior to established combustion. As a result of this inherent propellant stability, hybrid motors have historically proven difficult to ignite. State of the art hybrid igniter designs continue to require solid or liquid reactants distinct from the main propellants. These ignition methods however, reintroduce to the hybrid propulsion system the safety and complexity disadvantages associated with traditional liquid or solid propellants. The results of this study demonstrate the feasibility of a novel direct …

Transportation Economics And Energy, Ali Soltani Sobh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Transportation is one of the major energy consuming sectors in the United States. The continued growth in fuel consumption not only increases dependency on foreign oil but also causes environmental issues due to the emissions of greenhouse gas (GHG). High gasoline consumption in the US transportation sector not only raises concerns regarding national energy security, but also poses many questions regarding the resulting environmental impacts of greenhouse gases emissions. Improvement in automobile fuel economy, increase the use of natural gas vehicles and electric vehicles have been proven to be as the policies in controlling oil demand and GHG emissions in …

The Effect Of Polydimethylsiloxane Substrate Modification On A549 Human Epithelial Lung Cancer Cell Morphology And Biomechanics, Sherissa A. Ward

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The function of cells is dependent on factors including chemical, physical, and mechanical stimuli. A compilation of these factors make up the cellular niche. Though the impact of chemical stimuli has been a known factor for many years, the impact of mechanical and physical stimuli are areas of recent interest now being studied. Previous studies on mechanical and physical stimuli have shown a large impact on various aspects of cellular function.

The effects of cancer are wide spread throughout the entire population. The majority of cancer research and treatment is regarding intracellular chemical pathways. Yet, many forms of cancer are …

Growth Performance, Ruminal Fermentation Characteristics, And Economic Returns Of Growing Beef Steers Fed Brown Midrib, Corn, Silage-Based Diet, Christopher Scott Saunders

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sustainable beef production is extremely important to the beef cattle industry. Sustainability influences the environment, overall profits, and public concerns. One
factor that influences sustainability is the composition of cattle feed. This study compared conventional corn silage (CCS), which is most commonly used in beef steer feed, to brown midrib corn silage (BMR). Steers fed the two different diets were compared to determine differences in the areas of growth/animal performance, ruminal fermentation (digestion), and economic returns. The study included 24 beef steers randomly assigned to one of two treatment groups. Treatment groups were a total mixed feed ration that included …

An Investigatory Study Of Relationships Among Selected Theoretical Components Of Letter-Writing Fluency, Pamela C. Reutzel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Research that shows the need for letter-writing fluency as a foundation for being able to attend to higher-level thinking skills in writing calls for more research as to what the components of letter-writing fluency actually are and how they are related to writing efficiency. To study the components of letter-writing fluency, four assessments were used to evaluate 49 kindergarten students’ letter writing abilities. These assessments were made in December of their kindergarten year. The first assessed subskill was letter-naming fluency (LNF), which has previously been shown to be predictive of reading ability. The other two subskills that were assessed focus …

Aqueous Solvation Method For Recombinant Spider Silk Proteins, Justin A. Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spider silk is a remarkable material that has recently garnered significant international interest due to its broad applicability and natural composition. Spider silk fibers demonstrate unparalleled mechanical properties and their biocompatability will allow them to replace products currently on the market such as fibers, threads and sutures that are made from traditional polymers. As spiders cannot be farmed, an emphasis in the Lewis lab is being placed on producing recombinant spider silk proteins (rSSP) in a variety of hosts, including alfalfa, goats, silkworms and Escherichia. coli. To this end, alfalfa, goats and silkworms are being generated with unique rSSP's …

A Translational Investigation Of Positive And Negative Behavioral Contrast, Megan A. Boyle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Applied behavior analysts implement research-based techniques to improve behavior. However, research with nonhumans suggests that intervening to improve behavior in one context may result in a worsening of that same behavior in another context (behavioral contrast). Although there are clinical implications of behavioral contrast, the vast majority of research on contrast has been conducted with nonhuman animals. Results from basic research suggest that contrast is influenced differentially depending on whether a change in conditions follows versus precedes a given context. For example, a child might encounter three contexts each day: home, school, and daycare. An intervention to reduce the child’s …

Modeling Transportation Planning Applications Via Path Flow Estimator, Seungkyu Ryu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The current practice for modeling in the field of transportation planning is through a four-step travel demand forecasting procedure (i.e., trip generation, trip distribution, mode choice, and traffic assignment); the practice is commonly referred to as the four-step model. Although such a modeling approach has become standard practice, it is deficient in several areas. Specifically, (1) it lacks capability for modeling non-motorized modes such as bicycles, (2) it is inadequate for modeling multiple vehicle types sharing the same roadway space, and (3) it is difficult to apply to small communities with limited resources. This dissertation recognizes these deficiencies and responds …

Where The Action Is: An Analysis Of Partisan Change In House Of Representatives Open Seat Elections, 2000-2014, Kyle B. Wallace

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this research is to better understand what causes partisan change in House of Representatives open seat elections from 2000-2014. Despite being the source of the majority of freshman entering the House and traditionally having a higher rate of partisan change, open seats receive less attention in the political science literature than seats involving incumbents. The most comprehensive look at open seats came from Ronald Keith Gaddie and Charles S Bullock III in their 2000 book Elections to Open Seats in the U.S. House. Since 2000, very little research has been done to update the ever-changing environment …

Advancement Of Computing On Large Datasets Via Parallel Computing And Cyberinfrastructure, Ahmet Artu Yildirim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Large datasets require high processing power to compute, high-speed network connections to transmit, or high storage capacity to archive. With the advent of the internet, many in the science community and the public at large are faced with a need to manage, store, transmit and process large datasets in an efficient fashion to create value for all concerned. By example, large environmental researchers analyze large map data to extract hydrologic information from topography. However, processing these data and other tasks is hard – sometimes impossible – in minimal resource environments such as desktop systems.

This dissertation demonstrates novel approaches and …

Mechanical Properties Of Kenaf Composites Using Dynamic Mechanical Analysis, Thomas A. Loveless

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Natural fibers show potential to replace glass fibers in thermoset and thermoplastic composites. Kenaf is a bast-type fiber with high specific strength and great potential to compete with glass fibers.

In this research kenaf/epoxy composites were analyzed using Dynamic Mechanical Analysis (DMA). A three-point bend apparatus was used in the DMA testing. The samples were tested at 1 hertz, at a displacement of 10 μm, and at room temperature.

The fiber volume content of the kenaf was varied from 20%-40% in 5% increments. Ten samples of each fiber volume fraction were manufactured and tested. The flexural storage modulus, the flexural …

Representations Of Us Acts Of Extra-Territoriality As Illustrated In Pakistani-English Political Cartoons, Aina S. Niaz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The significance of Pakistan as an international state cannot be downplayed. Not only is Pakistan the first Islamic state to develop its nuclear power, but Pakistan has served as an important geostrategic state to the US on several occasions. The US-Pakistan geopolitical relationship was most vividly highlighted during the final years of the Cold War; and has reemerged again in the Global War on Terror. This thesis will examine Pakistani-English political cartoons to examine the way US extra-territoriality is represented visually. Approximately 2940 political cartoons are collected from four Pakistani-English newspapers: Dawn, The Express Tribune, The Nation, …

Improvement Of Nutrient Utilization Efficiency, Ruminal Fermentation And Lactational Performance Of Dairy Cows By Feeding Birdsfoot Trefoil, Rachael G. Christensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Condensed tannins (CT) are compounds that have shown potential to reduce the environmental impact of dairy farming waste products. In two live animal studies and a continuous culture study, it was hypothesized that feeding birdsfoot trefoil (Lotus corniculatus, BFT), a CT-containing legume, would improve nutrient utilization, milk, and component yield of dairy cows compared with feeding alfalfa hay or grass pasture in two studies, while feeding BFT forage would decrease methane production and improve rumen fermentation in addition to concentrate supplementation was the hypothesis of the third study. Reduction in milk urea nitrogen (MUN) and …

Sources Of Authority For Leadership And Instructional Technology Coaches' Diffusion Of High Access Teaching And Learning, Gregory M. Proffit

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this qualitative study was to use a leadership theory to explore the professional work of three school-based instructional technology coaches. The leadership theory is drawn from Thomas Sergiovanni’s Moral Leadership: Getting to the Heart of School Improvement.

The study used typical qualitative data gathering techniques: participant observations, informal and formal interviews, and the collection of representative workplace professional documents. A single researcher spent two school years in district office meetings and in three secondary schools gathering qualitative data.

The data were analyzed for bureaucratic, psychological, technical rational, professional, and moral sources of authority for leadership. The data …

The Effect Of A Class-Wide Training On Prosocial Bystander Behaviors, Charity Deanne Barnes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to decrease school bullying by teaching defending steps and increasing incentives for bystanders, students who witness bullying but who are not necessarily involved in the violence. An established bullying prevention program was modified to increase the likelihood that bystanders would defend victims of bullying behaviors. The findings of the study suggested that bullying behavior decreased and defending increased. Further, acceptability of the intervention and the skills taught to children were rated as moderately high across all classrooms.

Mitigation Of Medusahead (Taeniatherum Caput-Medusae) Through Grazing And Revegetation On The Channeled Scablands Of Eastern Washington, Clinton A. Stonecipher

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A large portion of the historical steppe and shrub-steppe habitats in eastern Washington have been altered through biotic and abiotic processes resulting in the annual grass medusahead becoming a large component of the altered vegetation. Experiments were conducted to determine: 1) if supplementing cattle with protein would help increase utilization of medusahead, 2) the grass species that could establish in the region, and 3) if mechanical disturbance would aid in such revegetation efforts. Cattle grazing medusahead-infested rangeland increased consumption of medusahead after all forage matured due to a reduction in the quality of forage alternatives. Cattle supplemented with protein increased …

Negative Reinforcement Through Contingent Easy-Task Presentation, Cicely Irene Nickerson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Escape from instructional demands is one of the most common functions of problem behavior. Some research suggests that a switch from difficult to easy tasks may function as a reinforcer for problem behavior. This is of particular concern for situations in which easy tasks are part of the intervention procedure to reduce problem behavior. This project examined the reinforcing effects of a switch from low-probability (low-p) to high-probability (high-p) tasks for individuals whose problem behavior was maintained by escape from demands. It also provided preliminary evidence as to the quality of reinforcement provided by a switch from low- high-p tasks. …

Effectiveness, Facilitator Characteristics, And Predictors Of The Premarital Interpersonal Choices And Knowledge (Pick) Program, J. Wade Stewart

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

There are two studies in this dissertation. Both are about a program called “PICK a Partner.” The first study looked at how the program went for 682 people from the community who were taught PICK. These people ranged in age from 18 to 25. Those in attendance were given questions at the beginning of the program about their thoughts, perceptions, and knowledge regarding dating relationships. They were given these same questions at the end of the program. The scores on the questions at the end of the program were compared with scores on the questions at the beginning of the …

Water Decision-Making Under Uncertainty, Augustina Yaa Oye Odame

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation is made up of three separate studies under the unifying theme of “Water Decision-Making under Uncertainty.” The first study analyzed a farmer’s decision to invest in a more efficient irrigation system given uncertainty about future water supplies and his post-investment efficiency. It found the price at which farmers would no longer produce to be a bigger consideration in irrigation investment than previously thought. It also found support for a careful identification and consideration of all significant sources of uncertainty in order to create better policy incentives for irrigation technology investments.

The second study extended the first to allow …

Two Types Of Conformal Antennas For Small Spacecrafts, Salahuddin Tariq

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spacecraft and vehicular bodies often require antennas that are conformal to their surface. The advantage of this choice is that they do not suffer from air drag or breakage and can be formed into any desirable shape. We can make them to operate at those frequencies at which simple wire antennas will require considerably longer length. Our thesis is about conformal antenna design for two space projects. The first project involves an array of patch antennas placed on multi-layer cylindrical substrate. Four of these antennas are S-band and four of them are GPS-band antennas. The second project deals with the …

Greater Sage-Grouse Seasonal Habitat Models, Response To Juniper Reduction And Effects Of Capture Behavior On Vital Rates, In Northwest Utah, Avery Cook

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The greater sage-grouse (Centrocercus urophasianus; sage-grouse) is a species of conservation concern in Utah and across their range throughout the western US and southern Canada. Sage-grouse decline is primarily a result of declines in sagebrush habitat on which sage-grouse depend for winter, summer, nesting, and brood habitat. Detailed site-specific knowledge of sage-grouse ecology and distribution in needed to effectively conserve the species. To expand knowledge of local populations within the West Box Elder Sage Grouse Management Area (SGMA) in NW Utah and gain insights into the effectiveness of vegetation treatments intended to benefit sage-grouse, I radio marked and …