Digital Commons Network^™

Fish Community Impacts And Conservation Implications Of A Novel Barrier On The San Juan River, Utah, Zachary T. Ahrens

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Stream fragmentation and non-native species introductions are among a suite of anthropogenic disturbances shaping the structure and function of freshwater ecosystems. The impacts of such alterations contribute to the global decline of stream fish biodiversity and may be synergistic in their effects. For example, the Colorado River basin’s unique native fish assemblage is imperiled not only by numerous dams and diversions, but also by threats of predation and competition for limited resources from non-native fish species. On the San Juan River, Utah, a recently formed fish barrier prevents upstream movement of native and non-native fish. The goal of this project …

Habitat Selection By Desert Carnivores: How Water, Intraguild Predation, And Prey Impact Animal Space Use, Nadine A. Pershyn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Across North America large carnivores have lost nearly half of their historic range, creating openings for smaller (< 15 kg) carnivores to take over their ecological roles. Coyotes (Canis latrans) have seen a significant range expansion, including into arid deserts. It was believed that the addition of artificial water sources by humans allowed coyotes to expand into desert ecosystems where they were previously unable to survive. The kit fox (Vulpes macrotis) is a small, desert-adapted carnivore with declining populations that faces threats from coyotes of intraguild predation. This is when carnivores compete over the same prey, and the larger carnivore (intraguild predator) kills the smaller carnivore (intraguild …

Evaluating Methods For Pathogen Spillover Detection And Forecasting In Desert Bighorn Sheep (Ovis Canadensis Nelsoni), Grete E. Wilson-Henjum

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Managers mitigate the effects of disease on wildlife populations by detecting outbreaks and predicting disease transmission. Bighorn sheep (Ovis canadensis) populations face threat from the introduced pathogen Mycoplasma ovipneumoniae (M. ovipneumoniae). In the eastern Mojave Desert, managers detect pathogen outbreaks in desert bighorn (O. c. nelsoni) through aerial population surveys, which produce irregular and coarse population information. Furthermore, managers model the risk of M. ovipneumoniae transmission amongst desert bighorn populations, however these models assume that desert bighorn space use is unchanging across years. Here, I evaluate methods used by managers to detect disease outbreaks …

Probabilistic Verification For Modular Network-On-Chip Systems, Jonah W. Boe

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Modeling physical systems with formal analysis tools can help in the design of more fault-proof systems, by helping to determine if unpredictable or unwanted behavior may occur. Probabilistic verification further advances such processes, by providing quantitative information about the system. More complex systems can especially benefit from formal modeling and verification, as testing the physical system in every possible condition manually, can be extremely complex, and often impossible.

There is a growing interest in the application of Network-on-Chip (NoC) systems. NoCs can help simplify communication between the subsystems of many technologies, including the ever more complex multicore processors being produced. …

A Questionnaire Survey Of Student Engagement Among First-Generation College Students In Engineering, Abigail Lehto

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

First-generation college (FGC) students are defined as students whose parents do not have a bachelor's or graduate degree. FGC students tend to face more overall challenges in the college environment than their continuing-generation counterparts. Often, FGC students have lower grade-point-averages (GPAs) and are less likely to graduate than their peers. In majors like engineering, the struggles that first-generation college students face can be further magnified. This quantitative study examines the activities FGC students in engineering engage in based on the National Survey of Student Engagement (NSSE). Questions from the NSSE cover different educational activities and are categorized into ten educational …

Consequences Of Host Life Cycles For Symbiont Genome Evolution, Ashley Elizabeth Dederich

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Aphids are small insects that feed exclusively on plant sap, a notoriously low source of nutrients due to the high sugar content and low amino acid content. To make up for these deficiencies in nutrition, aphids harbor Buchnera aphidicola, a bacterial endosymbiont that resides in a specialized organ called the bacteriome. B. aphidicola provides essential amino acids and vitamins for the aphid in exchange for a safe place to live. Over the course of the symbiosis (established 160 million years ago), B. aphidicola has lost much of its genome, including essential genes for cell envelope synthesis, DNA replication and …

Social Factors Driving Grouping Dynamics In Bighorn Sheep Ewe, Toni Proescholdt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding and predicting movement is critical for conservation planning and disease risk mitigation, and important environmental drivers of animal movement have received extensive attention in the ecological literature. Social factors surrounding group fission and fusion events also directly affect movement. However, these events are infrequently measured in the wild and rarely linked to underlying mechanisms such as relatedness, agreement in reproductive status, or shared life stage. While some social factors cannot be directly observed in the field, individual animals congregating in groups and moving about a landscape can. In animal societies, groups may merge together in a fusion event, and …

Generative Neural Network Approach To Designing And Optimizing Dynamic Inductive Power Transfer Systems, Andrew Pond Curtis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Electric vehicles (EVs) offer many improvements over traditional combustion engines including increasing efficiency, while decreasing cost of operation and emissions. There is a need for the development of cheap and efficient charging systems for the future success of EVs. Most EVs currently utilize static plug-in charging systems. An alternative charging method of significant interest is dynamic inductive power transfer systems (DIPT). These systems utilize two coils, one placed in the vehicle and one in the roadway to wirelessly charge the vehicle as it passes over. This method removes the current limitations on EVs where they must stop and statically charge …

Using Genome Analysis Methods To Screen Lactococcus Starter Cultures For Bitter‐Related Genes And Establish A Differentiation Method Using Qpcr For Lactococcus Lactis And Lactococcus Cremoris Species In Cheddar Cheese, Brantzen R. Wood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Consumers of Cheddar cheese expect consistent flavor and texture in the cheese they eat. Cheese flavor and texture is highly influenced by the bacteria cheese makers add during cheese production. These bacteria are generally responsible for the flavors and textures consumers associate with Cheddar cheese and are referred to as starters.

Sometimes during cheese manufacture off-flavors and textures can arise that make the cheese unappealing to eat. One such flavor that is off putting is bitterness. The bitter taste in cheese arises while the cheese is aging and is largely due to the same flavor producing starters added to the …

Young Children's Nutrition, Growth, And Cognitive Development In The Ecuadorian Amazon, Kristin N. Murphy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The first few years of life are viewed as a critical period for development. Children who do not grow and develop well in these early years can experience life-long negative implications. Many children under the age of five in Ecuador suffer from high rates of malnutrition, stunting (low height-for-age), and delayed cognitive development. This dissertation aims to better understand why children from Ecuador, specifically from the Amazon region, are experiencing such high rates of delayed development. Fifty children and their mothers living in the Amazon region of Ecuador participated in this research study.

First, interviews were conducted by an Ecuadorian …

Daytime Versus Nighttime Sprinkler Irrigation Of Two Urban Crops In A Semi-Arid Climate At High-Elevation, Samikshya Pyakurel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nighttime irrigation scheduling is a longstanding water conservation approach to reduce evaporative losses in Utah's semi-arid, urban landscapes. However, residential demand now exceeds system capacity, and the efficiency of the practice has come under question. Therefore, the objectives of this study include: 1) quantify whether a water savings exists between day and night irrigation with a water balance and energy balance approach, and 2) analyze microclimate and crop quality effects to determine any changes to evaporative demand or plant stress by irrigation timing. In 2019, we established 12 field plots in North Logan, UT (41.77° N, -111.81° W, 1380 m …

Increasing Production Of Therapeutic Mabs In Cho Cells Through Genetic Engineering, Charles Barentine

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Between 2014 and 2018, the global market for therapeutic monoclonal antibodies (mAbs) rose from $60 billion to $115.2 billion with a projected value of $300 billion by 2025. These molecules are used to effectively treat some of the most challenging illnesses from auto-immune diseases to cancer. While mAbs are highly valuable with potent applications, their production at scale remains an outstanding challenge. These molecules are largely produced in Chinese Hamster Ovary (CHO) cells that require highly specific conditions to produce a useful product.

Genetic engineering presents one solution to overcome productivity limits. With the advent of CRISPR (clustered regularly interspaced …

Avian Species Distribution Models: Using Location Data To Inform Management Decisions, Marilyn E. Wright

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Both state and federal wildlife agencies strive to conserve and protect wildlife and their habitats as an important public resource. Applied management decisions often rely on being able to obtain data that can efficiently and effectively enhance the understanding of these systems for informing management actions. Wildlife managers often focus efforts on a small subset of species from an ecosystem, typically called focal species, who can serve as surrogates for understanding the health and function of the system. Models that consider how these focal species interact with the ecosystem are often used to better understand important aspects of their life …

Bugs, Bullets And Birds: Factors Affecting The Health And Survival Of Ferruginous Hawk Nestlings In The Intermountain West, Ellis A. Juhlin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ferruginous Hawks are a bird of prey species that nest in sagebrush steppe and grassland habitat. These birds are threatened by habitat loss and fragmentation from urbanization, rural development, oil and natural gas extraction, habitat treatment projects, and wildfires, and experiencing widespread population declines across their breeding range. Because of this, Ferruginous Hawks (FEHAs) have been deemed a Species of Greatest Conservation Need by state management agencies in Utah, Idaho, Wyoming and Nevada. The health and survival of Ferruginous Hawk (FEHA) nestlings is crucial to long-term population viability. Understanding the threats these birds are facing as nestlings can provide valuable …

Extreme, Positive Geomorphic Change In A Historically Degraded Desert River: Implications For Imperiled Fishes, Tansy T. Remiszewski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rivers comprise some of the most unique and biodiverse ecosystems on the planet with their waters supporting both human societies as well as the organisms that make these rivers their home. Large rivers like the Colorado are often highly regulated and diverted in order to support human residence in arid regions like the desert Southwest, and these water diversions often have dramatic, negative impacts on the natural flow regime of the river. These impacts leave large reaches of the river dry, reduce the river’s capacity to transport sediment, cause channel and habitat homogenization, and significantly reduce the amount of suitable …

Seed Ecology And Regeneration Processes To Inform Seed-Based Wetland Restoration, Emily E. Tarsa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wetlands provide immense value to wildlife and humans but have been degrading rapidly around the world. One major challenge is the loss of native plant species in wetlands, which limits the ability of wetlands to function as they should. Restoring wetlands requires a combination of removing the cause of degradation (such as invasive plant species) and, in many cases, actively returning native plants to the site especially via seeding. Further, early plant life stages are the most vulnerable for plants and is often the time in which sown species die and fail to establish. Thus, understanding how and why seeds …

Development Of In Situ Second-Order Nonlinear Optical Scatterings For Molecular Behaviors At Aerosol Surfaces, Yuqin Qian

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Aerosol particles are one of the most important components of the atmosphere. During the growth of aerosol particles, they directly or indirectly affect air quality, human health, and environmental chemistry. Therefore, understanding the chemical and physical properties of such particles is an important scientific, engineering, and medical issue. The growth of aerosol particles in the atmosphere is closely related to the chemical structure at its surface, as well as the heterogeneous reactions which take place at and below the particle’s surface. However, there is a lack of suitable surface-specific analytical techniques which directly measure the chemical structure of aerosol particle …

The Relationship Between Bird Species Richness And Human Appropriation Of Net Primary Productivity, Kaeli Mueller

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As humans harvest increasing amounts of biomass, it is crucial to gain an understanding of how much energy is being appropriated and the impact that this could have on ecosystems and biodiversity. The primary way in which humans impact biodiversity loss is through land use change. One way of quantifying the impact of land use change is through human appropriation of net primary production (HANPP). This measurement represents the total amount of energy derived from photosynthesis that humans remove from ecosystems and appropriate for their own use. My research studies the relationship between HANPP and bird species richness at the …

Dust Deposition Changes Production, Chlorophyll-A And Community Composition In Mountain Lakes, Jiahao Wen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Increasing quantities of dust emitted from semi-arid soils, agricultural soils, and urban regions are blown to remote mountain lakes in the American West. Remote mountain lakes lacking local nutrient inputs and presenting simple food webs that are easily affected by climate changes. Dust can carry nutrients (e.g., nitrogen and phosphorus) to mountain lakes and potentially enhance algae growth and change algal communities. However, experimental tests of this hypothesis are lacking. Using in situ experiments, we investigated the effects of dust enrichment on the production, biomass, and primary algal species in three mountain lakes in the American West. We found that …

Nest‐Site Selection, Success, And Response To Predators By Cinnamon Teal And Other Ground‐Nesting Ducks In The Wetlands Of Great Salt Lake, Utah, Mark E. Bell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The wetlands of Great Salt Lake once supported hundreds of thousands of nesting ducks each year. In recent years, the number of nesting ducks in the same area was a fraction of those historic numbers. While many species of ducks do not rely on these wetlands for primary nesting habitat, cinnamon teal (Spatula cyanoptera) do. Great Salt Lake and its associated wetlands are in the heart of the cinnamon teal breeding range, and once supported half of the continental population.

These wetlands are unique from other wetlands where waterfowl nest because they are artificially created using dams to hold …

Functional Characterization Of The Newly Discovered Type V Crispr-Cas Protein Cas12a2, Dylan J. Keiser

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Similarly to people, bacteria are under the treat of infection by viruses. To circumvent these threats, bacteria evolve complex immune systems. Our understanding of some of these immune systems has led to many advancements in the field of Biotechnology including tools that made expressing proteins for study in a lab easier, tools that revolutionized the feasibility of gene editing, and tools that could change the way we think about viral diagnostics and cancer therapeutics. A certain type of immune system that bacteria use to fight virus is called a CRISPR system. Presented here is work to understand the function of …

Investigations Of Prokaryotic Defense Systems, Hannah Domgaard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bacteria are constantly threatened with infection by mobile genetic elements (MGE) such as bacteriophage and plasmids. Bacteriophage and plasmids require the bacteria's cellular infrastructure to replicate their genomes. Rampant replication can lead to cell death which is one reason why bacteria have developed a diverse array of immune systems to prevent or limit infection. This thesis studies three types of bacterial immune systems, type IV-A CRISPR-Cas (Clustered Regularly Interspaced Short Palindromic Repeat –CRISPR associated), type V-A2 CRISPR-Cas systems, and Wadjet systems.

The type IV-A system lies adjacent to a dinG-like helicase gene. Research has shown that this system can target …

Insecticide Susceptibility And Resistance Detection In Phlebotomus Argentipes Sandflies (Diptera: Psychodidae: Phlebotominae), Shawna M. Hennings

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Leishmaniasis is an understudied disease found predominantly in high heat and humidity areas. The disease is transmitted by sandflies which are blood-feeding, biting insects. There is currently no known vaccine for any form of leishmaniasis and treatment imposes a significant economic impact on already poor and marginalized populations, as well as severe, lingering side effects for afflicted individuals. Annually, there are millions of people around the world afflicted with a form of Leishmaniasis that is transmitted by species of sandflies. The primary sandfly population control method for over half a century has been indoor residual spraying using insecticides. The selective …

Immunological Tradeoffs And The Impacts Of Urbanization On The Reproductive Ecology And Physiology Of The Side-Blotched Lizard (Uta Stansburiana), Emily E. Virgin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Investing resources into reproduction can limit energy available to other competing demands, such as fighting off an infection; yet, both processes are necessary for organisms to survive and pass on their genes to the next generation. These strategies often follow patterns associated with lifespan, such that shorter-lived animals are more likely to invest more resources into reproduction over survival, and vice versa in long-lived animals. However, environmental change caused by urbanization can disrupt these relationships, and the within- and transgenerational costs of urbanization on females and offspring are unknown. I address these uncertainties in three research chapters to better understand …

Assessing Post-Fire Revegetation Efforts In Box Elder County, Utah, Using The Rangeland Analysis Platform, Rayce Bryan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

After fires occur in western rangelands, land management agencies commonly perform vegetation treatments and reseeding projects. The West Box Elder Coordinated Resource Management Group expressed concern regarding the difficult process of determining outcomes from the many post-fire revegetation projects undertaken on rangeland of Box Elder County, Utah. This research attempted to compile and clarify the fire and treatment history of the county and produce an assessment of the outcomes from each unique post-fire treatment in West Box Elder County. Also produced was a database of post-fire revegetation outcomes in published literature.

Unique treatment polygons were identified and then subset according …

Approaches To Supplementing Silicon In Soilless Media And The Value Of Silicon In The Mitigation Of Drought Stress, Mackenzie Grace Dey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Silicon (Si) is not considered an essential element for plants to complete their lifecycle, but is known to be beneficial for plants under environmental stress such as drought. Unlike natural soils, Si is minimally bioavailable in soilless media. With indoor agriculture and greenhouse production increasing, the benefits of Si have been seen and Si should be supplemented. This work aimed to characterize and quantify the dissolution of Si from media substrates and additives to achieve a steady-state release of Si in soilless media. Typical media components such as coconut coir, peat moss, perlite, rock wool, sand, and vermiculite minimally released …

Human Appropriation Of Net Primary Production Through Crops, Grazing, And Forestry In The U.S. From 1997 To 2012, Suman Paudel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation conducts a county-level analysis of human appropriation of net primary production (HANPP) harvested from crops, timber and grazing in the conterminous United States in the years 1997, 2002, 2007 and 2012. This study consists of three manuscripts (Chapters 2, 3, and 4). The first study quantifies net primary production in US counties in 1997, 2002, 2007 and 2012. The detailed HANPP study conducted concludes that HANPP is a valuable footprint tool for analyzing land use intensity and agricultural ecosystems. The second manuscript shows how HANPP is an improved or modernized ecological footprint and is a sustainable indicator as …

Low Resource Assay For Tracking Sars-Cov-2 In Wastewater, Julissa Van Renselaar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wastewater based epidemiology (WBE) allows for the tracking of nucleic acid of SARS-CoV-2 in wastewater which gives the opportunity for the public and government officials to be informed about the infectivity of the virus in a community. Advances have been made in WBE that have allowed for higher performance, lower resource use, and faster turnaround time. An adapted concentration method of spin column direct extraction has yielded a proxy virus recovery of 83%, consumable cost of $2.01 per sample, and a turnaround time of 0.33 hour/sample. Other concentration methods have lower proxy virus recoveries, comparable cost, and comparable turnaround time. …

Carbon Sinks And Sources In Great Salt Lake: Consequences Of Declining Lake Levels, Melissa Cobo Arias

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Globally, saline lakes are experiencing declining water level as a consequence of climate change, water diversions for human consumption, and management strategies that do not account for changing climate and drought conditions. Great Salt Lake (GSL) is a large saline lake in Utah, USA, and is, as most saline lakes, experiencing decreasing lake levels which may impact local carbon cycling. It is unknown how lakebed drying affects processes that control carbon sequestration and carbon emissions to the atmosphere. The goal of this research was to measure various biological processes that use, create, and transform carbon in GSL to understand the …

Statistical Challenges And Methods For Missing And Imbalanced Data, Rose Adjei

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Missing data remains a prevalent issue in every area of research. The impact of missing data, if not carefully handled, can be detrimental to any statistical analysis. Some statistical challenges associated with missing data include, loss of information, reduced statistical power and non-generalizability of findings in a study. It is therefore crucial that researchers pay close and particular attention when dealing with missing data. This multi-paper dissertation provides insight into missing data across different fields of study and addresses some of the above mentioned challenges of missing data through simulation studies and application to real datasets. The first paper of …