Life Sciences Commons^™

Development And Application Of A Reverse Genetics System For Zika Virus, Jordan C. Frank

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Zika virus (ZIKV) has emerged in many regions of the world, with infection outcomes spanning from no apparent illness to crippling nervous system disease. ZIKV and its close relatives, West Nile virus, Japanese encephalitis virus, dengue virus, and yellow fever virus are primarily transmitted by mosquitoes. Three ZIKVs were selected: MR-766 (Uganda, 1947), P6-740 (Malaysia, 1966), and PRVABC-59 (Puerto Rico, 2015), whose place of origin and time of isolation differ substantially. Stable, complementary DNA (cDNA) copies of the three ZIKV RNA genomes were cloned to examine the significance of viral and host genetic variations in directing ZIKV infection outcomes. Using …

Interactions Between Fire Severity And Forest Biota In The Central Sierra Nevada: Formation And Impact Of Small-Scale Fire Refugia And The Effect Of Fire On Forest Structure Predictive Of Fisher (Pekania Pennanti) Den Habitat, Erika M. Blomdahl

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fire is a natural and essential component of forests in western North America. Fire maintains biodiversity through the creation of different habitat types, and regular fire rotations reduce the accumulation of woody fuels and thick understory plant densities that give rise to catastrophic fire. The practice of fire exclusion has altered western forests and increased the risk of widespread change under rising temperatures projected for the 21^st century. To manage for the reintroduction of fire it is critical that we understand the interactions between fire and forest biota in recently fire-suppressed forests.

In Chapter 2, I studied the formation …

The Abiotic And Biotic Controls Of Arctic Lake Food Webs: A Multifaceted Approach To Quantifying Trophic Structure And Function, Stephen L. Klobucar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Arctic is warming faster than any other region of the globe. To conserve and manage many thousands of lakes across arctic landscapes, scientists need to understand historic and present conditions within these lakes to predict how the lakes, and the organisms that inhabit them, may respond to a changing climate. The goal of my research was to improve our understanding of what physical, chemical, and biological factors contribute to: 1) how lake food webs are assembled; and, 2) how these food webs may change in the future. First, I used long-term observations and lab experiments to determine how fish …

A Needs Assessment Of Arizona Agricultural Education Equine Science Curriculum, Emily Tobler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Like any other agricultural industry, many different career paths in the equine field are becoming more technologically advanced. To adapt to technological progress, current standards need to be integrated into school-based agricultural education courses to properly train and teach students about current industry standards. In addition to equine science curriculum development, emphasis must also be focused on providing assistance to secondary-school-based agriculture teachers so they can effectively teach industry-based equine science objectives in their programs.

The equine curriculum objectives were measured in terms of perceived importance by equine professionals and post-secondary equine educators as well as Arizona school-based agriculture teachers. …

Comparison Of Methods For Extracting Lactobacillus Wasatchensis Dna From Broth Media, Milk, And Cheese For Subsequent Pcr-Based Analyses, Tyler Allen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Western Dairy Center at Utah State University funded this project as part of its BUILD Dairy program with support from the dairy farmers of Idaho, to investigate the problem of splits that form in cheese during storage. The bacteria, Lactobacillus wasatchensis had previously been identified as a cause of unwanted gas production in cheese and the defects then make the cheese unsuitable for cutting into slices.

The project team proposed a two-year, $150,912 project to investigate methods for determining the presence of this bacterium in cheese by extracting DNA from the cheese and looking for DNA that was specific …

Plant Evolutionary Response To Climate Change: Detecting Adaptation Across Experimental And Natural Precipitation Gradients, Jacqueline J. Peña

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Global climate change is a real-time problem that presents threats to many species. Climate change can alter ecosystems and may lead to species extinction. Species can respond to climate change by moving to a better environment or adapting. Therefore, it is necessary to rely on several approaches and perspectives to anticipate ecological impacts of climate change. A common strategy uses models to understand how populations respond to different climate scenarios. Ecological models have helped us understand population persistence, but they often ignore how populations adapt to environmental stress. Adaptive evolution has been ignored because it was assumed that evolution was …

Interactions Between Biochar And Compost In Organic Winter Wheat Production And Soil Quality Under Dryland Conditions, Phearen Kit Miller

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Organic wheat grown under dryland conditions encounters challenges such as limited nutrients and water. Maintaining organic wheat production requires solutions to these problems in order to retain economic sustainability for the farmers.

Research on biochar and compost have been conducted globally. Despite well known benefits of compost on soil and crop production, few organic farmers apply compost to their fields. Research on biochar is still new. Biochar is charcoal created from pyrolyzing agricultural material under conditions of low oxygen and high heat. Many studies claim that biochar is a valuable soil amendment for improving organic production and reducing environmental pollution …

Identification Of Sperm Chromatin Proteins As Candidate Markers Of Stallion Fertility, Chelsea C. Ketchum

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During spermatogenesis, histones are largely replaced by transition proteins and protamines in normal stallions. Incomplete nucleoprotein exchange results in the abnormal retention of histones and transition proteins, which is an indicator of poor sperm quality. Equine nucleoprotein exchange has not previously been investigated in detail, so that equine sperm chromatin quality problems, which are often responsible for poor breeding performance of stallions, are not well understood. In order to characterize chromatin remodeling events in stallion spermatogenesis and to identify proteins indicative of sperm chromatin defects, such as excessive amounts of histones, we identified antibodies that recognize equine testis-specific proteins of …

A Simple Metabolic Switch May Activate Apomixis In Arabidopsis Thaliana, David Alan Sherwood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Apomixis, asexual or clonal seed production in plants, can decrease the cost of producing hybrid seed and enable currently open pollinated crops to be converted to more vigorous and higher yielding hybrids that can reproduce themselves through their own seed. Sexual reproduction may be triggered by a programmed stress signaling event that occurs in both the meiocyte, just prior to meiosis, and later in the egg just prior to embryo sac maturation. The prevention of stress signaling and the activation of a pro-growth signal prior to meiosis triggered apomeiosis, the first half of apomixis. The same approach was used prior …

An Evaluation Of Bull Trout Movement Dynamics In The Walla Walla River, Courtney Newlon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bull trout are a fish species listed as threatened under the Endangered Species Act. Historically, they ranged from Northern California at the southernmost extent, into Canada at the northern most extent, and east into Nevada and Montana. Bull trout are highly migratory and require large, unfragmented habitats to persist and are thus highly susceptible to human induced land-use practices. The goal of my thesis was to obtain a better understanding of bull trout movement patterns in the Walla Walla River, Washington using complimentary techniques; Passive Integrated Transponder (PIT) technology and otolith microchemistry. PIT tags can be injected into a fish …

Geospatial Modeling Of Land Cover Change In The Chocó-Darien Global Ecoregion Of South America: Assessing Proximate Causes And Underlying Drivers Of Deforestation And Reforestation, José Camilo Fagua

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Chocó-Darien Global Ecoregion (CGE) in South America is one of 25 global biodiversity hotspots prioritized for conservation. I performed the first land-use and land-cover (LULC) change analysis for the entire CGE in this dissertation. There were three main objectives: 1) Select the best available imagery to build annual land-use and land-cover maps from 2001 to 2015 across the CGE. 2) Model LULC across the CGE to assess forest change trends from 2002 to 2015 and identify the effect of proximate causes of deforestation and reforestation. 3) Estimate the effects of underlying drivers on deforestation and reforestation across the CGE …

Investigation Of The Molecular Mechanisms Of The Shigella Type Iii Secretion System Tip Complex, Abram R. Bernard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Shigella are bacteria that are responsible for millions of infections and hundreds of thousands of deaths every year. The emergence of antibiotic resistant Shigella adds to the potentially devastating effect that these bacteria can have on human health. Shigella flexneri utilize specialized molecular machinery called the Type III secretion system to infect humans and cause disease. Research of this machinery promises to provide the knowledge, tools, and direction for the development of new avenues to combat shigellosis. This dissertation presents studies of two Shigella proteins, invasion plasmid antigens C and D (IpaC and IpaD). These proteins are part of a …

Blue And Red Light Effects On Stomatal Oscillations, Trevor R. Ballard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plants absorb CO₂ through pores in their leaves called stomata, which are known to open and close in response to myriad environmental and physiological triggers. We demonstrate that blue light inhibits stomatal aperture oscillations in both the guard cells and surrounding tissue layers, whereas these oscillations continue under the influence of red light. This observation of blue light behavior agrees with recent research and suggests another physiological pathway for oscillations.

The Macroinvertebrate And Fish Communities Of In-Stream Beaver Ponds In Northeastern Utah, Susan Washko

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Beavers were virtually extirpated from North America during the fur trade, but populations have since recovered. Dams built by recolonizing beaver alter stream habitat by forming deep, slow ponds within the streams. Such changes to the habitat is likely to have consequences for organisms such as macroinvertebrates and fish. The objective of this study was to identify the differences in the macroinvertebrate and trout community in beaver ponds and lotic (e.g. flowing reaches of a stream) reaches in tributaries to the Logan River in northeastern Utah. The macroinvertebrate community of beaver ponds had fewer species, fewer numbers, and lower biomass …

Efficacy Of Translocation As A Management Tool For Urban Mule Deer In Utah, Channing R. Howard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An increase in urbanization in the United States has led to an increase in human-wildlife interactions with deer (Odocoileus spp.) which have been able to adapt and thrive in these urban environments. In Utah, urbanization has occurred along the Wasatch Front which was once traditional mule deer (Odocoileus hemionus) winter range habitat. This urban expansion coupled with an increasing use of these urban areas by mule deer, have led to increasing conflicts with deer. Overabundant urban deer have led to increased concerns over safety from deer-vehicle collisions, and damage to personal property including gardens and landscaping. …

Influence Of Environmental Variables On Survival Rates Of Pronghorn (Antilocapra Americana) Neonates Across Idaho, Brett R. Panting

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was completed to better understand pronghorn antelope (Antilocapra americana) populations found throughout Idaho. Antelope were studied in three separate and distinct study areas. The Big Desert, Camas Prairie, and Little Lost and Pahsimeroi valleys were all selected as study sites. Idaho Department of Fish and Game (IDFG) is concerned with current pronghorn populations found throughout Idaho. Pronghorn are a valued big game species found in Idaho. Increasing pronghorn populations in Idaho is a focus of IDFG.

We captured and VHF-collared pronghorn fawns found in our three study areas. Fawns were monitored daily with telemetry equipment for …

Landscape Planning For Climate Change Resilience In The Southern Rockies, Jeffrey D. Haight

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The unique species, ecosystems and landscapes of the Western United States are experiencing unprecedented pressures from climate change, creating new challenges for conservation. As temperatures rise and patterns of precipitation shift, plant and wildlife species have been shifting their ranges to new areas in search of more suitable climates, building groupings of species that are historically unfamiliar. These climate -driven migrations place an additional burden on species that are already threatened from habitat loss and other human-related activities. The impacts of climate change are of particular concern in landscapes that have long been conserved and managed based on the ecological …

Sociodemographic And Climatic Factors Shaping The Development Of Drought Policies In Major U.S. Cities, Riana S. Gayle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In most parts of the world, drought is an inevitable and natural occurrence. However, as the climate continues to warm, and populations grow and expand, the negative impacts of this extreme weather event are predicted to become more pronounced. This leads many communities and stakeholders to question what is being done to prepare society for widespread drought? The following research determines different social and atmospheric characteristics that affect a city’s likelihood of having a drought policy in place.To do this, a thorough search was conducted at the city level to determine where drought policies are currently located in theU.S. The …

Evaluation Of Antioxidant Properties Of Native Utah Berries And Their Potential For Use In Meats, Xiaoxi Wang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In industry, antioxidants are added to prevent changes that affect quality due to oxidation, such as the development of off flavors, unacceptable odors and discoloration. New resources that are familiar to consumers and may work as antioxidants should be studied.

The changes in antioxidant activity were determined for four freeze-dried native wild berry powder species in Utah, including skunkbush (Rhus trilobata), chokecherry (Prunus virginiana), river hawthorn (Crataegus douglasii) and silver buffaloberry (Shepherdia argentea), during cold storage (-20 °C) for 6 months. The total antioxidant activity was stable in most of the berry …

Patterns Of Use Before And After A Labeling Intervention Among Collegiate Division I Athletes At A Fueling Station, Julie A. Buzzard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Fueling Station at Utah State University was created to provide pre-workout fueling and post-workout recovery foods to the Utah State University athletes. The athletes use an online survey to mark what foods they selected after each visit to the Fueling Station.

There is a large amount of research on the lack of sports nutrition knowledge in collegiate athletes, but there is little information on the dietary intake of athletes, the education of athletes, and the education of macronutrient timing in athletes.

A food labeling system named “Gain Your Edge” food labels that targeted the education of timing was created …

Assessing The Ecological Implications Of The Altered Flow And Sediment Regimes Of The Rio Grande Along The West Texas-Mexico Border, Demitra E. Blythe

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Large, exotic (those whose headwaters are in distant places) rivers are some of the most unique and diverse ecosystems on earth. Because they often flow through a multitude of biomes and climates, their waters are a vital resource not only for the organisms that inhabit these rivers, but for human societies as well. Thus, large rivers, like the Rio Grande, that flow through arid and agricultural regions are highly regulated and diverted. Regulation and dewatering upset a river’s natural flow regime (e.g., magnitude, duration, timing of large flood events), subsequently impacting the river’s ability to transport its sediment supply, and …

The Nesting Ecology Of Woodpeckers In The Eastern Cascades And Their Interactions With Nest Competitors And Predators, Samuel D. Cowell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Woodpeckers create nesting cavities for other birds and animals in forests. This creates dynamic interactions between both woodpeckers and these other animals. Using video cameras, we documented direct behavioral interactions between nesting woodpeckers and other animals in the Eastern Washington Cascades during the 2015 and 2016 breeding seasons. Additionally, we offered 937 students in a General Biology laboratory course to participate in this original research opportunity and described and the impact the experience had on the participants as well as the researchers.

In 2015, Western Blubebirds took over two active Black-backed Woodpecker nests by physically attacking the woodpeckers. In 2016, …

Organic Matter Sources, Composition, And Quality In Rivers And Experimental Streams, Julia E. Kelso

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Organic matter (OM) is often considered the “currency” for ecosystem processes, such as respiration and primary production. OM in aquatic ecosystems is derived from multiple sources, and is a complex mixture of thousands of different chemical constituents. Therefore, it is difficult to identify all the sources of OM that enter and exit aquatic ecosystems. As humans develop undisturbed land, the rate at which terrestrial OM (e.g. soil and plants) and associated nutrients (e.g. nitrogen) enters rivers has increased. Increased nutrients may lead to increased primary production from aquatic plants and algae, potentially causing eutrophication and harmful algal blooms. …

The Effects Of Enhanced Flows On Community Structure And Ecosystem Functioning In A Montane Utah River System, Joshua A. Epperly

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Due to growing human demands for freshwater within the last century, manmade flow alterations are now a common characteristic of rivers worldwide. Alterations to the volume and timing of flows in rivers are known to negatively impact aquatic biodiversity, biological productivity and ecosystem functions such as nutrient cycling. While previous research has focused on the effects of flow reductions and spates, there is a lack of knowledge on how high flows across longer timespans (i.e. ‘enhanced flows’) impact the structure of river communities and the integrity of ecosystem functions.

The Utah Reclamation, Mitigation and Conservation Commission has expressed interest in …

Development And Characterization Of Reporter-Expressing Zika Viruses, Michael E. Woolley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In recent years, Zika virus (ZIKV) has garnered worldwide attention due to its epidemic spread throughout the Americas and due to the newly recognized link between ZIKV infection and neurological diseases, including microcephaly and Guillain-Barré syndrome. ZIKV is a mosquito-borne member of the genus Flavivirus, which includes the other prominent human pathogens Japanese encephalitis virus, West Nile virus, dengue virus, and yellow fever virus. Many questions about the biology of ZIKV and how it causes disease remain unanswered. Furthermore, there currently are no vaccines or licensed antiviral drugs available to treat ZIKV infection. The goal of this study was to …

Land Cover And Use Change In Utah: A Comparison Of Field- Vs. Aerial Image-Based Observations, Jennifer Lynn Bakken

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Image-based Change Estimation program (ICE) was developed by the US Forest Service Forest Inventory & Analysis (FIA) program and the Geospatial Technology Applications Center in response to the 2014 Farm Bill calling for more timely and accurate estimates of land cover and use change. ICE monitors change throughout the US on a state by state basis by assessing each FIA plot using high resolution imagery from two dates in time. In the western US, FIA measures 10% of the plots each year to report on status, trends, and sustainability of our Nation’s forests. However, this 10 year cycle misses …

U.S. Consumers’ Perception, Intention, And Purchase Behavior Of Grass-Fed Beef, Elizabeth K. Crandall

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this research study was to compile regional profiles of the consumers who intend to consume grass-fed beef in the U.S. and to create marketing strategies that would assist producers in marketing their product to consumers. The researcher sent an online survey to a panel of 484 consumers across the U.S. to learn about their perceptions of and intention to purchase grass-fed beef.

Respondents had a weak, positive attitude toward purchasing grass-fed beef but had low knowledge of production practices. These consumers had a desire to eat healthier; however, they wanted meat that was priced right and had …

Impacts Of Phragmites Australis Management On Wetland Plant Community Recovery, Seedbank Composition, And The Physical Environment In The Chesapeake Bay, Eric L. G. Hazelton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Biological invasions have adverse economic, cultural, and ecological effects worldwide. Among the most impactful in North America is the invasion of Phragmites australis (Phragmites), a large-scale clonal grass that rapidly colonizes wetlands. Phragmites crowds out native plants and alters habitat for native fauna. In doing so, Phragmites also alters human access to water resources and has adverse economic effects, including decreasing property value, inhibiting recreational use, and limiting populations of game species.

The efforts described in this dissertation are a component of a large, multidisciplinary effort to better understand the anthropogenic stressors to Chesapeake Bay, Maryland, at the …

Effects Of Livestock Grazing Management Practices On Greater Sage-Grouse Nest And Female Survival, Seth J. Dettenmaier

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The decline in greater sage-grouse (Centrocercus urophasianus; sage-grouse) populations across western North America has been primarily attributed to loss and fragmentation of their sagebrush (Artemisia spp.) habitats. This habitat loss is largely the result of increased human activities, with grazing by domestic livestock as the most predominant land use across the sagebrush ecosystem in North America. The goal of my research was to increase our understanding of the effects of livestock on sage-grouse populations. I reviewed the peer-reviewed literature for all published studies that reported potential effects of grazing on grouse species worldwide. I found that there …

Development And Fitness Consequences Of Onshore Behavior Among Polar Bears In The Southern Beaufort Sea Subpopulation, Kate M. Lillie

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Polar bears (Ursus maritimus) are experiencing rapid and substantial changes to their environment due to global climate change. Polar bears of the southern Beaufort Sea (SB) have historically spent most of the year on the sea ice. However, recent reports from Alaska indicate that the proportion of the SB subpopulation observed onshore during late summer and early fall has increased considerably. Previous research suggests that the number of polar bears onshore is linked to sea ice conditions and the availability of subsistence-harvested whale carcasses, which are referred to as bone piles. My objectives were to determine the development …