Digital Commons Network^™

Microbiome Assembly And Function In The Solitary Mason Bee, Osmia Lignaria (Megachilidae), Bailey Crowley

All Graduate Theses and Dissertations, Fall 2023 to Present

Animal-microbe interactions can influence host biology, ecology, and evolution. The assembly and function of microbes found within animal hosts oftentimes depends on which species are involved. Advances in sequencing technologies have permitted the exploration of host-microbe interactions in a variety of animals, including bees. Early research aimed at understanding the microbiomes of social bees, such as honey bees and bumble bees, found that microbes prevent the spoilage of stored pollen, breakdown indigestible nutrients into smaller molecules available for uptake by the host, and also protect the host from pathogens. When environmental stressors, such as increased temperatures, disrupt the microbiome, the …

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 …

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.

Ensemble Machine Learning At The Edge Using The Codec Classifier Structure And Weak Learners Guided By Mutual Information, Aj Beckwith

All Graduate Theses and Dissertations, Fall 2023 to Present

The Codec Classifier is a low-computation, low-memory tree ensemble method that dramatically improves feasibility of image classification on resource-constrained edge devices. It achieves advantages over other tree ensemble methods due the separation of encoder and decoder tasks in the classifier. The encoder partitions feature space, and the decoder labels the regions in the partition. This functional separation of tasks enables the encoder design (partitioning) to be guided by maximizing the mutual information (MI) between class labels and the features (i.e. the encoded representation of the data) without regard to the error performance of the classifier. Experiments show maximizing MI leads …

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 …

Method Development For The Extraction And Analysis Of Per- And Polyfluoroalkyl Substances (Pfas) In Wastewater And Biosolids, Victoria Krull

All Graduate Theses and Dissertations, Fall 2023 to Present

Per and poly-fluorinated alkyl substances (PFAS) are manufactured chemicals that have water and grease repellant properties and do not readily biodegrade. PFAS are present in many consumer products and end up in waste systems and the environment. Studies have shown that PFAS can have adverse health effects on humans and animals.

There are many challenges to processing and analyzing samples containing PFAS including: adsorption of PFAS to equipment, contamination from equipment containing PFAS, and the high sensitivity needed to analyze for PFAS in the parts per trillion detection range. The United States Environmental Protection Agency (EPA) has been developing methods …

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 …

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 …

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 …

Reburns Of High Severity Patches: Effects On Ponderosa Pine Regeneration And Plant Community Composition, Nadav Mouallem

All Graduate Theses and Dissertations, Fall 2023 to Present

The area burned in high severity fire as well as the proportion of fires burning at high severity have been increasing in southwestern ponderosa pine (Pinus ponderosa) forests since the 1980s. These fires often contain large patches (>100 ha) of 100% tree mortality, which are a concern as they can lead to the establishment of nonnative species and conversion to non-forest vegetation. And, with an increasing amount of fire on the landscape, high severity patches are reburning. However, information on the ecological trajectory of reburns of high-severity patches as well as the utility of remotely sensed burn severity metrics …

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, …

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 …

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 …

Anomaly Detection On Wind Turbine Blades Using Aerial Imaging, Image Processing, And Deep Learning, Bridger Kohl Altice

All Graduate Theses and Dissertations, Fall 2023 to Present

In reaction to rising global temperatures and carbon dioxide emissions, many countries are looking to use energy sources other than fossil fuels. One such source of energy is wind energy, which can be harvested by wind turbines. By rotating at high speeds, the blades of these large turbines are able to convert wind energy to kinetic energy, which is then converted to electricity usable by the power grid. Traditional methods for inspecting these turbines for damages are expensive, unsafe, and susceptible to human error. These turbines are so tall and so large that inspectors run the risk of falling from …

Siwa's Influence On Alexander The Great's Self-Presentation, Luke Boardman

All Graduate Theses and Dissertations, Fall 2023 to Present

This thesis analyzes the changes in Alexander the Great’s public image and how his visit to the Oracle of Ammon was a catalyst for these alterations. Examining moments of Alexander in isolation, his adoption of ostentatious habits, and enrobing himself in foreign attire and culture reveals a connection to his time in the Egyptian desert where Alexander was promised eventual authority over all mankind. The post-Siwa Alexander used these tools to leave behind the Hellenistic leader and become the Lord of Asia.

Filter Incidence Narrowband Infrared Spectrometer For Space-Based Methane Measurement And Plume Detection, Bruno Mattos

All Graduate Theses and Dissertations, Fall 2023 to Present

Monitoring methane emissions from space is essential for reducing global warming. This dissertation introduces the Filter Incidence Narrowband Infrared Spectrometer (FINIS), a compact, lightweight instrument designed for nanosatellites to accurately measure methane emissions. FINIS uses two innovative imaging spectrometers to capture the Earth's reflected light, focusing on the strongest methane absorption feature at 1666 nm. By using tiled interference filters, each imager collects detailed spectral data, allowing precise methane detection. FINIS has been significantly improved from its prototype to its space-ready version, set to launch on the ACMES CubeSat in late 2025. The new design includes a binocular optical system …

Evidence For Partitioning? A Comparison Of Thermal Niche In Three Species Of Sympatric Lizards In Northeastern Utah, Kristopher B. Pedersen

All Graduate Theses and Dissertations, Fall 2023 to Present

Lizards actively maintain a narrow range of body temperatures through behavioral thermoregulation and microhabitat selection. Body temperature plays a critical role in many physiological processes. As a result, there is a range of body temperatures at which a lizard’s reproductive success (fitness) is maximized, known as the lizard’s thermal niche. There is strong evidence linking the available temperatures, or thermal properties of a microhabitat, to success in maintaining body temperatures within a preferred set range. Microhabitats have differing thermal properties, and so have different relative quality. Because thermal properties are limited in space and time, competition for high quality microhabitat …

Shedding Light On Past Ice-Free Intervals In Northwest Greenland: Luminescence Dating Of The Base Of The Camp Century Ice Core, Hawke Woznick

All Graduate Theses and Dissertations, Fall 2023 to Present

The goal of this thesis is to provide greater resolution on the age and character of the subglacial sediment recovered from the base of the Camp Century ice core, northwestern Greenland. Geochemical analysis indicated that the upper sub-ice sediments were geochemically different and experienced greater weathering than the basal unit underlying a one-meter silty ice lens. Analysis of feldspars within the very fine sand fraction indicates they are dominated by potassium feldspar. Sediment was dated using luminescence, which provides an age for the last time sediment was exposed to light. Luminescence analysis returned ages around 420 thousand years old, which …

Invasion Potential Of Nonnative Fishes Through A Large Western Dam Into A Prized And Vulnerable Ecosystem, Barrett T. Friesen

All Graduate Theses and Dissertations, Fall 2023 to Present

Native river fish face threats from habitat fragmentation, water overallocation, invasive species establishment, and powerful synergies amongst these factors. In the Colorado River Basin, USA, these threats coalesce at Glen Canyon Dam (GCD), which impounds the Colorado River to create Lake Powell, a reservoir inhabited by nonnative fish species. There is widespread concern low water level in Lake Powell may allow nonnative fish to escape through the dam, adversely affecting native fish species downstream in the Grand Canyon. In this study we characterized the seasonal distribution of nonnative fishes in the vicinity of GCD and identified environmental conditions that may …

Cislunar Optimal Robust Trajectory Design With Corrective Maneuvers, Scott J. Kelly

All Graduate Theses and Dissertations, Fall 2023 to Present

One common method for determining how to get from point A to point B is by finding the most fuel-efficient path. This is a common method for spacecraft trajectory designers also. Without any random or unexpected occurrences this path is called the deterministic optimal trajectory. Sometimes unexpected events happen that result in deviating from the most fuel-efficient path; while driving, you may encounter a detour. Naturally, we tend to return to the original fuel-efficient path and continue the journey. Similar deviations happen in space. The rocket delivering a spacecraft to orbit likely will not deliver exactly to the intended starting …

Herbivore Effects On Litter Quality And Quantity And Influences On Carbon Cycling, Taylor Saunders

All Graduate Theses and Dissertations, Fall 2023 to Present

Plants are responsible for a large amount of the movement of carbon (C) and nitrogen (N) through terrestrial systems. One way that plants affect the movement of C and N is through plant litter inputs to soils. Plant litter highly influences processes such as soil microbial respiration and decomposition. Herbivores, such as geese in the Yukon Delta National Wildlife Refuge, affect these processes by changing litter quality and quantity. These changes cause differences in soil respiration, microbial communities, and nutrient turnover. However, because geese influence litter quality, quantity, and habitat characteristics simultaneously, it is not yet clear which of these …

Shaking Off The Rust: Unraveling The Depositional And Diagenetic History Of Enigmatic Ferroan Dolostones In The Cambrian Bright Angel Formation, Tonto Group, Grand Canyon, Joseph J. Clevenger

All Graduate Theses and Dissertations, Fall 2023 to Present

Within the siliciclastic-sediment-dominated Bright Angel Formation (BAF) of the iconic Cambrian sedimentary strata (Tonto Group) in Grand Canyon National Park, Arizona, workers have identified and named prominent reddish-brown cliffs breaking up the generally slope-forming unit near, but separated from, its upper contact with the limestone-dominated Muav Formation, the "Rusty Brown Dolostones" (RBDs). Previous hypotheses suggest that the RBDs are chemically and physically altered tongues of the Muav Formation intercalated with the BAF at increasingly higher stratigraphic positions from west to east within the Canyon. A genetic association between the Muav Formation and the RBDs, as well as between the RBDs …

Predicting Individual Hiking Trail Intensity Using Statistical Learning, Kelci Hannan

All Graduate Theses and Dissertations, Fall 2023 to Present

Hiking is an increasingly popular choice for people wanting to engage in recreation and physical activity. It not only offers the many benefits of exercise but also the opportunity to explore nature and to socialize. To ensure that new hikers are prepared to hike and remain safe while on the trail, knowledge of a hiking trail's difficulty is important. Trail difficulty information is sometimes available at the trailhead if the trail is well-trafficked and maintained but is nearly always available online or through a hiking-specific mobile application, such as AllTrails. Both trailhead and online sources provide only one difficulty rating …

Trade-Offs In Lighting For Dic Strain Measurements In Vibration-Based Fatigue Testing, Jacob R. Rigby

All Graduate Theses and Dissertations, Fall 2023 to Present

Vibration based fatigue testing offers a fast and efficient method for determining the breaking point of a material. This method often uses a device, called a strain gage, to measure the deformation of a test sample at a single spot on the test sample. However, these strain gages often break before testing is complete. To overcome this premature break, a laser vibrometer is often used to measure the amount of movement or the speed of the test sample throughout the vibration test. The deformation measured by the strain gage is compared against the amount of movement or velocity of the …

Comparative Morphology And Development Of The Trigeminally Innervated Infrared-Imaging System In Boas And Pythons, Helen Bond Plylar

All Graduate Theses and Dissertations, Fall 2023 to Present

Boas and pythons use specialized sense organs called pit organs to detect radiant heat. Pit organs in these lineages occur in paired arrays along the upper and lower jaws and are served by the trigeminal nerve (the fifth cranial nerve and one of the largest). Information from the pit organs travels via branches of the trigeminal to the brain and ultimately is processed in the optic tectum, along with information from the visual system. That means these snakes effectively “see” heat. While studies of the pitviper infrared-imaging system are numerous, very few studies of this system in pythons or boas …

The Influence Of Business Development Areas On Leadership Positions Within Landscape Architecture Professional Practice, Catherine E. Frost

All Graduate Theses and Dissertations, Fall 2023 to Present

Landscape architecture is a discipline that connects natural, physical, and human sciences, and which operates as a professional design practice. While technical skills and design proficiency have historically been the focus of landscape architecture programs, the literature indicates a recognition of the indispensable role of entrepreneurial skills alongside design expertise (Marsh, 1928; Pray, 1911; Rice, 2017; Shepphard et al., 2018). However, there remains a scarcity of research specifically investigating business development skills within landscape architecture practice (Evans & Leccese, 1991; Gobster et al., 2010; Granet, 2021; Littlefield, 2015; Powers & Walker, 2009).

To bridge this gap, this study engaged in …