Digital Commons Network^™

The Interactions Between Drought Tolerant Corn Hybrids And Plant Water-Stress On Weeds And Their Host Capability For Spider Mites, Mercy Adhiambo Odemba

All Graduate Theses and Dissertations, Fall 2023 to Present

With climate change, it is predicted that more frequent high temperatures and drought severity will lead to an increase in damage caused by pests that thrive under these conditions. Spider mite outbreaks, for example, are associated with plant waterstress and there is evidence that some weeds are more resilient and adapted to drought than some crops, leading to major concerns for the management of these two pest types. Weeds directly compete with crops for limited resources, but what is unclear is which weeds harbor spider mites and whether they exacerbate the impact of spider mites on corn crops under water-stressed …

Computational Fluid Dynamics Modeling Of Air Demand For Fixed Cone Valve In Energy Dissipating Structure, Matthew S. Harames

All Graduate Theses and Dissertations, Fall 2023 to Present

Fixed cone valves are commonly installed as low-level outlet devices to discharge water from reservoirs. When discharging water, the fixed cone valves require an air vent to properly operate and maintain the valve. There is a current lack of published information regarding the accuracy of model studies to properly estimate the air demand on the full-size prototype. This research aims to help close that gap by providing data comparison between a model and prototype. Furthermore, computational fluid dynamics (CFD) simulations may be used to estimate the air demand, but the results of such have not been verified nor is information …

Stratigraphic Evidence For Indigenous Use Of Fire As A Dryland Agricultural Landscape Management Tool On The Northern Colorado Plateau, Mariah Walzer

All Graduate Theses and Dissertations, Fall 2023 to Present

While documented in ethnography and traditional ecological knowledge, Indigenous burning practices are rarely recognized in the archaeological record of the Great Basin and Colorado Plateau. I analyzed charcoal from an arroyo wall to understand the relationship between Indigenous farmers and fire at the Cub Creek archaeological site (AD 300-1300) in Dinosaur National Monument. The size, shape, and amount of charcoal in each sediment layer indicates the fuel types (woody or grassy) and relative size and/or intensity of fires. I compared my data to a precipitation reconstruction for the area to evaluate the influence of climate on fire activity. The results …

Implementing General Moment Equations For Parallel Closures In Nimrod, Hankyu Lee

All Graduate Theses and Dissertations, Fall 2023 to Present

Understanding how magnetic fields impact plasma transport is essential for improving the efficiency of thermonuclear fusion power plants. To address the transport problem, both plasma fluid equations and Maxwell’s equations must be solved. To solve these equations, it is necessary to derive closure relations that allow the system to be closed. Previous closure models are useful for describing the behavior of high-collisionality plasma but are not effective at low collisionality. To obtain closure relations valid for low collisionality, the first-order drift kinetic equation must be solved.

This study presents methods for numerically obtaining parallel closures for NIMROD code by deriving …

The Rise And Fall Of Elizabeth Holmes: Investigating Myths Within Media Coverage, Charlotte Emelia Williams

All Graduate Theses and Dissertations, Fall 2023 to Present

When Elizabeth Holmes became the youngest female billionaire in 2014, news media framed her as the next Steve Jobs due to her similarities as a dropout, a passionate industry disruptor, and a visionary. When she was discovered as a fraud in 2018, coverage framed her as a feminine, seductive monster who duped everyone. I analyzed the media coverage in both years to uncover myths that guided these narratives and argue that these news frames contributed to the large interest in her rise and fall while also reinforcing harmful ways of thinking toward success and female leadership.

California Condor Feeding Habitat, Vigilance, And Competition With Avian Scavengers In Southern Utah, Usa, Alex Blanche

All Graduate Theses and Dissertations, Fall 2023 to Present

Independent foraging is needed for the reintroduction of a species to be successful, but it can cause cascades in interconnected ecological communities. California condors (Gymnogyps californianus) were reintroduced to the Colorado Plateau in 1996, and the population has continued to grow with yearly releases of captive individuals. However, little is known about foraging behavior of condors and their potential competitors. Carrion is a risky food source, and there is a tradeoff between vigilance and feeding. Altering behavior can maximize caloric intake while minimizing risk. Here, I investigate habitat selection, vigilance, and interspecific interactions among condors, golden eagles ( …

A Position Allocation Approach To The Battery Electric Bus Charging Problem, Alexander Brown

All Graduate Theses and Dissertations, Fall 2023 to Present

With an increasing adoption of Battery Electric Bus (BEB) fleets, developing a reliable charging schedule is vital to a successful migration from their fossil fuel counterparts. In this work, a BEB charging scheduling framework that considers fixed route schedules, multiple charger types, and battery dynamics is modeled as a Mixed Integer Linear Program (MILP). The MILP is modeled after the Berth Allocation Problem (BAP) in a modified form known as the Position Allocation Problem (PAP). The optimization coordinates BEB charging to ensure that each vehicle remains above a specified charge percentage. The model also minimizes the total number of chargers …

Do Older Siblings Differentiate From Their Younger Siblings? Predictors And Longitudinal Correlates, Iliana Wilkinson

All Graduate Theses and Dissertations, Fall 2023 to Present

Families are a critical part of an individual's development, yet sibling influences on development are rarely studied. Siblings often share the same genetics and live in the same environment, yet many remark that they are nothing like their brothers or sisters. One proposed reason for these differences is sibling differentiation, a process by which individuals become different from their sibling in order to reduce conflict and rivalry as well as increase intimacy in the sibling relationship. To date, this process has been studied from the perspective of the younger sibling; the current study focused on older siblings. Using longitudinal data …

An Xrf Elemental Analysis Of Prosser Molded Beads From Southwest Oregon, Michele Hoferitza

All Graduate Theses and Dissertations, Fall 2023 to Present

Glass beads were brought to the North American continent by European explorers and traders beginning in the 17^th century. Native Americans quickly adopted beads as trade commodities and personal ornaments. Prosser beads were made predominately in France and Bohemia from the 1860’s to the 1970’s and can be found in archaeological contexts from coast to coast. In this study, elemental analysis using X-Ray fluorescence (XRF) technology is used to determine if there is a way to chemically discern where and when the beads were made.

Statistical analysis of three categories of elements was done to determine whether the creation …

Utilizing Bayesian Optimization In Technoeconomic Analyses For Integrated Energy Systems, Anthoney Griffith

All Graduate Theses and Dissertations, Fall 2023 to Present

Technoeconomic analysis is a key element in the study of integrated energy systems. The goal of this analysis is the sizing of technologies resulting in the best economic outcome for the system. The evaluation of this system involves sizing the components and simulating the resulting market to determine an outcome. This simulation incorporates multiple possible values of uncertain parameters like grid price and wind generation. This problem is currently approached with the gradient descent optimization method. An alternative approach, Bayesian optimization, sees success on simple problems of a similar nature to technoeconomic analyses. These results motivate applying Bayesian optimization as …

An Examination Of The Effects Of Prey Density, Mortality, Nutrients, And Foraging Tradeoffs On A System With Inducible Defenses: An Empirical And Theoretical Approach, Benjamin C. Ralston Daniel

All Graduate Theses and Dissertations, Fall 2023 to Present

To grasp the functioning and stability of ecosystems, it is important to understand species interactions. With many ecosystems becoming more imperiled from urbanization and anthropogenic influences it is important to understand ways in which species can adapt to rapid changes in their environment. Phenotypic plasticity is one such tool at nature’s disposal to initiate rapid change, where species with the same genetic makeup can have different expressed traits depending on their environment. Inducible defenses are one such form of phenotypic plasticity in which prey can express different levels and forms of defense depending on the threat of predation present in …

Development Of A High-Throughput Methodology For Vibration-Based Fatigue Tests, Brandon Alexander Furman

All Graduate Theses and Dissertations, Fall 2023 to Present

Global efforts towards the development of additively manufactured materials, biomaterials, metamaterials, self-healing materials, and composites have reached a staggering pace. With new materials being developed on a near-daily basis, it is more important than ever to be able to quickly and precisely quantify their mechanical performance. However, one of the most important mechanical properties, fatigue life, is notoriously time consuming to measure. Consequently, fatigue parameters are often calculated based on small sample sizes, resulting in high uncertainty of the measured parameters. In this dissertation a high-throughput approach to fatigue measurements is developed. This technique allows for multiple samples to accumulate …

Effects Of Winter Ticks (Dermacentor Albipictus) On The Reproduction Of Utah Moose (Alces Alces Shirasi), Samuel D. Robertson

All Graduate Theses and Dissertations, Fall 2023 to Present

Moose (Alces alces) are the largest and only solitary members of the deer family. The species can be found across many northern regions around the world. Moose are considered to have high intrinsic, recreational and ecological value. In recent years, there have been concerns about declining moose populations in portions of the species circumpolar range. Moose in Utah (Alces alces shirasi) belong to the Shiras subspecies, which is the smallest of the four subspecies found in North America. Utah moose are the southernmost naturally occurring moose population in the world. The Utah Division of Wildlife Resources …

Online Act For Caregivers: A Longitudinal Mixed Methods Study, Jacob D. Gossner

All Graduate Theses and Dissertations, Fall 2023 to Present

Family caregivers for people with dementia are a resilient population operating under stressful circumstances that can put them at risk of multiple negative outcomes. Existing interventions may be difficult for family caregivers to access due to time and transportation constraints; an alternative is online, self-guided interventions that caregivers can access from their own homes. The purpose of this dissertation is to evaluate the impact of ACT for Caregivers, a six session online, self-guided program based on the principles of Acceptance and Commitment Therapy. Participants had an average age of 61.93 (SD = 13.69), had been caregiving for an average …

Righting Reproductive Wrongs: A Rhetorical Analysis Of Special Topoi In Alberto Fernández’S Pro-Voluntary Interruption Of Pregnancy Speeches, Kymberlie Crosby

All Graduate Theses and Dissertations, Fall 2023 to Present

The reproductive rights movement argues that abortion rights are fundamental and necessary for women to enjoy their human rights. Politicians opposed to abortion rights around the world have made it clear that they plan to ban abortion both statewide and nationwide. A country that has proven to be successful in defending its reproductive rights is Argentina. In 2020, the Voluntary Interruption of Pregnancy Bill (Interrupción Voluntaria del Embarazo; IVE) democratically passed and legalized abortion throughout Argentina. Argentine President, Alberto Fernández, supported IVE and delivered a series of speeches over four years highlighting IVE and the progress that has succeeded each …

An Examination Of Inclusion Of Secondary Students With Disabilities In One Local School District, Brandon Brown

All Graduate Theses and Dissertations, Fall 2023 to Present

This survey was designed to examine the role of inclusion in a secondary school setting in one school district. The survey attempted to measure the attitudes, and opinions of general education school teachers, special education school teachers, administrators, and the parents of a student with a disability. The survey determined that most opinions agreed that students with disabilities deserved to be included in classes and extracurricular activities but what that would look like was different in all groups. Opinions even varied when looking at what the exact definition of inclusion was. Results from the survey showed opinions that teachers and …

Metal Assisted O2-Dependent Carbon-Carbon Bond Cleavage Of Β-Diketones And Flavonols, Stephen N. Anderson

All Graduate Theses and Dissertations, Fall 2023 to Present

Almost everything we interact with on a daily basis has been synthesized by chemists ranging from plastics, food preservatives, and medications. The diversity of synthetic molecules are achieved by the formation of new bonds between existing molecules and/or through the cleaving of bonds found in a molecule. There are uncountable amount of conditions reported to facilitate chemical reactions which all depend on the nature of molecules being used and the environment it is used in.

In recent years, more attention has been paid to identify chemical reactions that can use more environmentally favorable conditions and reduce the use of limited …

Healing Through Caring And Knowledge-Making In Everyday Food Practices Among Lgbtq+ Black, Indigenous, People Of Colour, Elizabeth Grace Wong

All Graduate Theses and Dissertations, Fall 2023 to Present

Three different models are used in this study to understand how everyday food practices carry healing potential through the interwoven process of caring and knowledge-making. Daily food practices reflect a mixture of tradition and modernity— borne out of our roots and our contexts. Anzaldúa’s (1987) Borderland Theory helps us understand how this mixture is made by people who straddle two borders or worlds and contest those confines. Chavez-Dueñas et al.’s (2019) HEART model names strengthening our cultural and familial traditions and roots as part of the broader processes of building cultural consciousness and connection, and engaging in collective healing. Finally, …

Soil Additives And Alternative Crops For Drought Defense In The Intermountain West, Tina M. Sullivan

All Graduate Theses and Dissertations, Fall 2023 to Present

The Western U.S. looks for water optimization and conservation as agriculture is the largest water diverter, and resources are pressured by urban growth, winter snowpack instability, and drought persistence. Agricultural producers have several potential options to optimize water use with different investments associated with them. Options with varying levels of risks and known management practices include alternative crops, soil wetting agents, and crop biologicals.

An alternative crop that grew incredibly fast in popularity was industrial hemp (Cannabis sativa) despite limited agronomic knowledge for best management practices. Field trials occurred (2020-2022) near Logan, UT to test a total of …

Environmental Physiology Of Medical Cannabis, F. Mitchell Westmoreland

All Graduate Theses and Dissertations, Fall 2023 to Present

Cannabis (Cannabis sativa L.) is increasingly being cultivated for industrial and medical uses. Medical cannabis is grown for cannabinoids and terpenes, compounds that continue to show promising therapeutic potential. Cannabidiol (CBD) and delta-9- tetrahydrocannabinol (Δ9-THC) are the two most common cannabinoids, but more than 150 have been identified in cannabis. The 2018 Farm Bill federally legalized cannabis containing less than 0.3% THC and high-THC medical cannabis is legal in 38 states. There is a need to understand environmental effects on yield and quality to ensure safety and quality for medical use.

The cultivation of medical cannabis is centered around …

Socially Valued, Ecologically In Decline: Place Attachment Influences Support For Management Actions In A Quaking Aspen Forest Impacted By Recreation, Soil Contamination, And Ungulates, Georgie Corkery

All Graduate Theses and Dissertations, Fall 2023 to Present

Quaking aspen (Populus tremuloides Michx.) spark strong emotional attachments among many people, yet they are ecologically in decline across North America. Aspen landscapes are also popular outdoor recreation destinations. Site-specific strategies are required for both managing for healthy aspen landscapes and enhancing the outdoor recreation experience. Our study investigated a highly-recreated and ecologically declining aspen forest in Summit County, Utah facing population decline. There were two distinct phases of data collection. First, we evaluated the condition of the aspen and identified potential management actions that could improve the condition of the aspen. Second, we surveyed people who visited the site …

Dynamics Of Climate And Tectonics On Surface Processes And Their Sedimentary Archives In The Colorado Plateau And Basin And Range, Usa And The Calabrian Forearc, Sicily, Natalie M. Tanski

All Graduate Theses and Dissertations, Fall 2023 to Present

Landscapes change over time in response to movements of the Earth’s crust and the effects of climate. This dissertation examines how these factors shape different landscapes, focusing on erosion of river canyons in elevated plateaus, how the transport history in quartz sand may be encoded in its properties, and how a paleo-delta has formed in response to sea-level change and fault displacement. I use dating techniques, field methods, and topographic analyses to offer insight into erosional patterns and rates in different landscapes.

Rivers can take a long time to adjust to changes in boundary conditions, even after those changes have …

To Pot Or Not To Pot: Understanding Technological Investment In Ceramics And Marine Mammal Oil Rendering In Kodiak, Alaska, Elizabeth Groat

All Graduate Theses and Dissertations, Fall 2023 to Present

Why do groups choose to use certain technologies, but not others? This study focuses on an especially confusing instance of this question: the adoption of pottery in Kodiak, Alaska. This event was strange for two reasons. First, by AD 1500, when Alutiiq ancestors in the Kodiak Archipelago began making pottery, their neighbors on the mainland had already been doing it for centuries—so why did they wait so long? Second, pottery is also only found in the south of the islands—so why did some people use it, but not others? Whale and seal are more abundant in southern Kodiak, so one …

Citizen Science Project On Urban Canids Provides Different Results From Camera Traps But Generates Interest And Revenue, Neville F. Taraporevala

All Graduate Theses and Dissertations, Fall 2023 to Present

As more people live in cities, wildlife increasingly encounters people. Coyotes (Canis latrans) and red foxes (Vulpes vulpes) are two carnivores that have easily adapted to urban environments causing them to come into conflict with people and their pets. Citizen science, where members of the community aid scientists in the collection of data, has emerged as a low-cost method of studying these species that can provide benefits to management agencies but may provide different results than traditional methods. We analyzed data collected by citizen scientists and data collected via motion-triggered camera traps to see how each …

Hydrogen Stable Isotope Constraints On Hydration Of Colorado Plateau Lower Crust From Oligocene-Miocene Navajo Volcanic Field Xenoliths, Shelby Dianne Litton

All Graduate Theses and Dissertations, Fall 2023 to Present

Understanding flat-slab subduction is crucial as it involves the horizontal movement of an oceanic plate beneath a continental margin over a long distance. This tectonic process is widespread yet not fully understood, particularly regarding how it influences the chemical makeup of the continental plate and recycling in the hydrosphere. By analyzing isotopes, which are variations of certain elements found in minerals and water, we can gain insights into the sources of chemicals and geological processes at play. Our study area included six locations within the Navajo volcanic field (NVF), a region in the Colorado Plateau. We analyzed 23 lower crustal …

Sparks, Belonging, And Relationships: High School Teachers' Use Of Developmental Context To Engage Students In Career Pathways, Dave Francis

All Graduate Theses and Dissertations, Fall 2023 to Present

The 4-H Thriving Model outlines how a foundation for youth sparks, belonging, and relationships can lead to short and long-term outcomes. This study explored how high school teachers in Utah integrate the elements of the foundation of the 4-H Thriving Model in environmental science and natural resources management classroom teaching. A mixed method of interviews and surveys was used to understand teaching practices. Teachers described helping students discover their interests (sparks), nurturing these interests, and linking them to careers using methods like guest speakers, field trips, contests, and student presentations. They also worked on creating a sense of belonging in …

The Drivers And Ecological Importance Of Streamflow Permanence For Native Salmonids: Evaluated At Multiple Spatio-Temporal Scales, Skylar Rousseau

All Graduate Theses and Dissertations, Fall 2023 to Present

In freshwater ecosystems, aquatic resources are distributed patchily across both space and time. Non-permanent streams, which go through periodic episodes of drying and rewetting, account for more than half of all streams in North America and help create much of the diversity that defines aquatic ecosystem form and function. While non-permanent streams have become increasingly common under climate change, we have a poor understanding of both their distribution across the landscape as well as how native stream fishes make use of them when they are flowing. I analyzed a large data set that spanned multiple decades across the northern Rocky …

Silica Fault Mirror Development Along The Cordillera Blanca Detachment Fault, Peru, Kayla Michelle Chaudoir

All Graduate Theses and Dissertations, Fall 2023 to Present

Earthquakes occur along planes of geologic weakness called faults. Thin, light-reflective surfaces on faults are called fault mirrors and often considered signatures of previous earthquakes along these faults. The Cordillera Blanca mountain range in the Peruvian Andes provides a natural laboratory to explore meter scale exposures of fault mirrors. Three naturally formed fault mirror samples were collected from the Cordillera Blanca detachment fault which runs along the edge of the Cordillera Blanca mountain range. Prior work on this fault reveals that it is capable of destructive earthquakes every few thousand years and is a significant earthquake hazard to the surrounding …

Informed Intervention Design, Deployment, And Analysis For The Computer Science Classroom, Jaxton J. Winder

All Graduate Theses and Dissertations, Fall 2023 to Present

Improving the teaching of computer science is a challenging task. Educators and computing education researchers devote large amounts of time, energy, and resources towards doing so effectively. One of the ways this is done is through research-informed design, deployment, and analysis of targeted interventions to the classroom. This thesis will detail research conducted at Utah State University targeting classroom interventions: centered around their design, deployment, and analysis.

One of these interventions aims to tackle student procrastination through the offering of “grace points”–forgiving a small amount of mistakes on a student’s assignment–for analyzing a homework assignment early. Through studying this intervention, …

Exploring Peer-Assisted Learning In A High-School-Based Suicide Prevention Intervention, Sterling R. Morris

All Graduate Theses and Dissertations, Fall 2023 to Present

This dissertation evaluated a form of teaching called peer-assisted learning in which people of similar ages and knowledge teach each other a subject. In this dissertation, peer-assisted teaching occurred in a suicide prevention organization called Hope Squad, which operates as individual chapters in high schools. The author first shared details from other researchers' studies on peer-assisted learning, then conducted two studies on this form of instruction in Hope Squad: The first study reported on the experiences peers have from learning from their peers, and the second study reported on peers' experiences teaching their peers. This dissertation may give researchers further …