Life Sciences Commons^™

Constraints On Patterns Of Abundance And Aggregation In Biological Systems, Kenneth J. Locey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding the mechanisms that structure biological systems is a primary goal of biology. My research shows that the biological structure is constrained in important ways by general variables such as the number of base pairs in a genome and the number of individuals and species in a community. I used a combination of macroecology, bioinformatics, statistics, mathematics, and advanced computing to pursue my research and published several peer-reviewed scientific manuscripts and open-source software as a result.

I was funded through a combination of fellowships and scholarships awarded by the Utah State University School of Graduate Studies, College of Science, and …

Optimizing Systems For Cold-Climate Strawberry Production, Tiffany L. Maughan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Producing fruits and vegetables in the Intermountain West can be challenging due a short growing season, extreme temperatures, and limited availability of irrigation water. This is particularly true of strawberries, where commercial production is limited due to late fall and early spring frosts that shorten the growing season. With the increasing demand for local produce as urban populations grow and as consumer buying habits change, growers are looking for ways to overcome these climatic challenges. High tunnels are one option growers can use. High tunnels are similar to greenhouses, but less expensive to construct and to maintain. Another way to …

Winter Waterbird Ecology On The Great Salt Lake, Utah, And Interactions With Commercial Harvest Of Brine Shrimp Cysts, Anthony J. Roberts

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Interactions among commercial fisheries and birds have been studied in open ocean ecosystems and at aquaculture facilities. On the Great Salt Lake (GSL), Utah, USA, a commercial harvest of brine shrimp (Artemia franciscana) eggs (i.e. cysts) occurs annually during fall and winter. Coinciding with commercial harvest is the use of the GSL by millions of waterbirds which has the potential to result in conflict among industry and birds. The objectives of my research were to examine fall and winter ecology of birds using the GSL and interactions with the brine shrimp cyst harvest. I examined the influence of temperature and …

Effect Of Predator Removal On Greater Sage-Grouse (Centrocercus Urophasianus) Ecology In The Bighorn Basin Conservation Area Of Wyoming, Elizabeth Kari Orning

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The decline of greater sage-grouse distribution and population densities across western North America has led conservation, research, and management objectives to focus efforts on understanding sage-grouse populations across their range. The purpose of this study was to gain a better understanding of direct and indirect predation effects on hen survival and nest success of sage-grouse. The project was conducted in Hot Springs and Park Counties in the Bighorn Basin of Wyoming. The study had three main objectives: 1) obtain and quantify the types and impacts of predators on sage-grouse hen survival and nest success, 2) compare the effect predator removals …

Characterization Of The Hydrogen Peroxide Stress Responses Of Bifidobacterium Longum And Bifidobacterium Animalis Subsp. Lactis, Taylor S. Oberg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Probiotics are living organisms which exert a beneficial health effect when consumed in sufficient numbers. Consumer interest in probiotics has increased dramatically in recent years prompting an increase in production and development of functional foods. One major problem is the decreased viability of probiotic bacteria during functional food production and storage and subsequent digestion due to environmental stresses. The most common probiotic strains belong to the genus Lactobacillus or Bifidobacterium. Due to the anaerobic nature of these bacteria, they lack the required defense mechanisms for oxidative stress inherent in aerobic microorganisms. This study examined the oxidative stress responses of …

Influence Of Mountain Pine Beetle On Fuels, Foliar Fuel Moisture Content, And Litter And Volatile Terpenes In Whitebark Pine, Chelsea Toone

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mountain pine beetle (Dendroctonus ponderosae Hopkins) has caused extensive tree mortality in whitebark pine (Pinus albicaulis Engelm) forests. Previous studies conducted in various conifer forests have shown that fine surface fuels are significantly altered during a bark beetle outbreak. Bark beetle activity in conifer stands has also been shown to alter foliar fuel moisture content and chemistry over the course of the bark beetle rotation.

The objective of this study was to evaluate changes to fine surface fuels, foliar fuel moisture and chemistry and litter chemistry in and under whitebark pine trees infested by mountain pine beetle. Fuels …

Determination Of The Expression Patterns Of Bovine Non-Classical Major Histocompatibility Complex (Mhc) Class I Proteins, Parveen Parasar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This project was funded by the United States of Department of Agriculture (USDA), which funds research aimed at improving production and animal health. The aim of this study was to advance knowledge of maternal immune tolerance to the fetus and mechanisms bovine non-classical MHC class I proteins employ to interact with immune cells and render them inert towards the fetus.

A fetus is a tissue graft inside the mother’s uterus yet must be accepted by the mother to maintain a successful pregnancy. Reproductive insufficiency and pregnancy failure are major causes of production loss in cattle, especially in cloned animals. Knowledge …

Climate Change And Plant Demography In The Sagebrush Steppe, Aldo Compagnoni

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We used demographic methods to address one of the main challenges facing ecological science: forecasting the effect of climate change on plant communities. Ecological forecasts will be crucial to inform long-term planning in wildland management and demographic methods are ideal to quantify changes in plant abundance. We carried out our research in the sagebrush steppe, one of the most extensive plant ecosystems of Western North America. Our research intended to inform ecological forecasts on an exotic invader, cheatgrass (Bromus tectorum). Moreover, we investigated the general question asking: to what degree competition among plants influences the outcome of ecological …

Presence And Function Of Tetrodotoxin In Terrestrial Vertebrates And Invertebrates, Amber N. Stokes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tetrodotoxin (TTX) is a potent neurotoxin found in a variety of species. This toxin has long been of concern to human health as it is found in puffer fish, which are a delicacy in Japan. Since the distribution of this toxin is so great, there are many questions regarding the evolution and ecology of organisms that have TTX. My research has focused on further investigating three topics with this research: production, predation, and identification of novel TTX bearing taxa. In order to perform this research I first refined a Competitive Inhibition Enzymatic Immunoassay methodology to quantify levels of TTX in …

Common Raven Density And Greater Sage-Grouse Nesting Success In Southern Wyoming: Potential Conservation And Management Implications, Jonathan B. Dinkins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Declines in the distribution and abundance of greater sage-grouse (Centrocercus urophasianus; hereafter "sage-grouse") in western North America over the past century have been severe. The goal of my research was to increase the understanding of factors influencing where sage-grouse hens placed their nests, how common ravens (Corvus corax: hereafter "raven") impacted sage-grouse nest success, and whether high raptor densities negatively impacted hen survival of sage-grouse. I compared raven and raptor densities at sage-grouse nest and brood locations to available habitat. I also assessed how sage-grouse positioned their nests and broods relative to proximity to man-made structures, …

Assessment Of Consumer Motivations To Attend Farmers' Markets, Their Preferences, And Their Willingness To Pay For Differentiated Fresh Produce: Three Essays, Jean Dominique Gumirakiza

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this public abstract is to present research objectives, societal benefits, and costs associated with this dissertation. This dissertation is one the outcomes of a three-year $155,450.86 project whose number is UTA01008. Kynda Curtis, Associate Professor, Department of Applied Economics proposed the project to assess consumer demand and purchase motivations for differentiated produce across direct marketing outlets. In general, this dissertation seeks to analyze consumer primary motivations for attending farmers’ markets, their preferences, and their willingness to pay for differentiated fresh produce. To accomplish this task, we develop three essays.

Specific objectives for the first essay are to …

Utilizing Remote Sensing And Geospatial Techniques To Determine Detection Probabilities Of Large Mammals, Patricia A. Terletzky-Gese

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Whether a species is rare and requires protection or is overabundant and needs control, an accurate estimate of population size is essential for the development of conservation plans and management goals. Wildlife science has traditionally relied on human observers in airplanes, helicopter, or ground vehicles to count the number of individuals seen during wildlife surveys. However, these traditional surveys of wildlife require significant resources, are difficult to conduct quickly and safely over remote and/or extensive locations, are disruptive to the studied species, and are prone to significant error due to unobserved or missed animals and multiple counts of single animals. …

Modeling Habitat Use Of A Fringe Greater Sage-Grouse Population At Multiple Spatial Scales, Anya Cheyenne Burnett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Greater sage-grouse (Centrocercus urophasianus; hereafter sage-grouse) are a prominent bird species of sagebrush-dominated landscapes across the western United States. Over the past 15 years, sage-grouse have gained international attention due to decreasing population trends despite management efforts. In 2010 the U.S. Fish and Wildlife Service designated this species as warranted for listing under the Endangered Species Act, but the listing was precluded by other species at higher conservation risk. Habitat loss, degradation, and fragmentation have been implicated as primary sources of declines in sage-grouse distribution and abundance. The Bald Hills population in southwestern Utah occupies an area with …

Selected Neuropharmacology Of Resurgence, Adam D. Pyszczynski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The reemergence of problem behavior (i.e., relapse) is a key concern in most behavioral interventions. Resurgence refers to the reappearance of a previously rewarded behavior when reward for an alternative behavior is also discontinued. It is especially relevant to the reappearance of problem behavior because many behavioral interventions discontinue reward for aberrant behavior while simultaneously rewarding an appropriate response.

Understanding the underlying neuropharmacology of behavioral phenomena such as resurgence is important because it helps elucidate the neural processes at the root of such behavior, and also has implications for pharmacotherapies. Existing information about the neuropharmacology of resurgence is scarce, but …

The Ecology And Genetics Of Schoenoplectus Maritimus, An Important Emergent Macrophyte, Across Diverse Hydrologic Conditions—Implications For Restoration, Amanda Clare Sweetman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wetlands in the Intermountain West are typically dominated by large monotypic stands of emergent wetland plants, are highly productive, and support millions of migratory birds as important stops along the Pacific Flyway. In systems with low species diversity, such as these, diversity within a species (intraspecific diversity) can play an important role in population fitness and ecosystem functioning and can impact restoration success. Our research was designed to inform future restoration and management activities by studying the pattern of diversity within and among natural plant populations, and by studying how hydrology and plant materials used in restoration (source and diversity …

The Micronutrient Profile Of The Typical American Diet Enhances Colorectal Carcinogenesis, Stephany Del Carmen Perez Monsanto

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The typical Western dietary pattern is characterized by the consumption of energy-dense, nutrient-poor foods and has been linked to increased risk of colorectal cancer (CRC). Our research group previously developed the total Western diet (TWD) that emulates typical human dietary intakes of macro- (carbohydrates, proteins, and fats) and micronutrients (vitamins and minerals) on an energy density basis for rodents. In the present study, we sought to determine the impact of TWD on biomarkers of metabolic syndrome and obesity in comparison to a commercial 45% fat diet used for models of diet-induced obesity (DIO diet) and the standard basal AIN93G diet, …

Causes And Consequences Of Local Variability In Aroga Websteri Clarke Abundance Over Space And Time, Virginia L.J. Bolshakova

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sagebrush steppe habitat is rapidly declining in the Intermountain West in both quality and quantity. Observed reductions in animal and bird populations associated with sagebrush, invasion of exotic annual grasses such as cheatgrass (Bromus tectorum), and other concerns with climate change have led to a growing awareness of the need to monitor and better understand the rate of habitat loss. Sagebrush lands are subject to periodic loss caused by insect feeding damage, and human activities have the potential to promote unnaturally high levels of such loss. The sagebrush defoliating Aroga moth, Aroga websteri Clarke (Lepidoptera: Gelechiidae), can kill …

The Phosphoramidase Competency Of Prototypical Phosphatase Catalytic Motifs, Mark P. Haney

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Phosphorylation of proteins is ubiquitous. Phosphorylation can activate proteins, deactivate proteins, assist in signaling, or serve other roles depending upon the biochemical pathway. Attaching phosphate to proteins is accomplished by enzymes called kinases; removing phosphate from proteins is accomplished by enzymes called phosphatases. Cells must regulate their biochemical pathways, and the antipodal roles of kinases and phosphatases represent the yin-yang of phosphorylation.

Phosphorylation of proteins is known to occur on serine, threonine, and tyrosine. This creates a phosphoester bond. Phosphoester bonds have a phosphorus-oxygen (P-O) bond. The ability of phosphatases to cleave such phosphoester bonds is well studied. Phosphorylation of …

Small Burnet (Sanguisorba Minor Scop.) Response To Herbicides Applied Postemergence, Ryan Lee Nelson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Small burnet is a relatively unknown plant that is commonly used in North America. It is a hardy, relatively long lived forb native to Eurasia that grows well in most of North America. It is considered to be excellent forage for livestock and wildlife and because of its evergreen nature there is interest in its use to extend grazing of pastures and rangelands into late fall and winter.

Popular sources reference its use in salads, ice drinks, with cream cheese, as a desirable garnish due to its distinct cucumber aroma and flavor. It is also reported to be a superb …

A Multi-Scale Investigation Of Factors Limiting Bull Trout Viability, Tracy Bowerman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Recent declines in many species of aquatic organisms have raised concerns about loss of biodiversity in river systems and the need to protect populations in peril. To conserve endangered species, scientists need to know information about the habitats organisms use throughout their life cycle and how environmental stressors cause populations to grow or decline. The goal of this research was to improve our understanding of the life-cycle requirements for bull trout (Salvelinus confluentus), a threatened freshwater fish species. I assessed environmental factors that affect bull trout egg incubation success and quantified juvenile bull trout movement patterns and survival …

Increased Production And Extraction Efficiency Of Triacylglycerides From Microorganisms And An Enhanced Understanding Of The Pathways Involved In The Production Of Triacylglycerides And Fatty Alcohols, Robert M. Willis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The continued increase in the demand for fossil fuels combined with their ever dwindling supply has prompted the search for a suitable alternative fuel. The research contained within this dissertation seeks to increase the lipid (fat) content of cellular feedstocks, improve extraction efficiencies of lipids, and to understand the pathways involved in the production of fatty alcohols and triacylglycerides, compounds commonly used in many industrial processes, from microbial feedstocks. This work has been done in an attempt to increase the overall economic viability of microbial biofuels production.

The production of biofuels from microalgae used as a feedstock allows for the …

Needs Assessment For Promoting Livestock And Equine Safety For Diné Youth, Karah L. Shumway

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This project was funded through the National Children's Center for Rural and Agricultural Safety and Health as part of the pilot study program for 2011-2012 fiscal year. The project team proposed a one-year, $19,991 project to conduct a formative needs assessment of Diné parents for the prevention of agricultural injuries to children who are helping farm or ranch. The assessment utilized a survey constructed of closed and open ended questions to gauge Diné farmers' and ranchers' perceptions of injury risks to children who live or work on an agricultural operation. Additional questions were asked to gauge Diné acceptance of an …

Roads And The Reproductive Ecology Of Hesperidanthus Suffrutescens, An Endangered Shrub, Matthew B. Lewis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We studied the pollination ecology of the endangered Utah desert shrub, shrubby reed-mustard (Hesperidanthus suffrutescens). We also studied the impacts that dust from unpaved roads has on successful reproduction. In addition, we looked at the relationship between the total number of plants, the spacing of plants, and reproduction. We found that shrubby reed-mustard requires pollinators for successful pollination. Pollinators include many small native bees from the genera Andrena, Dialictus, and Halictus. Additionally, we found that reproduction of shrubby reed-mustard is limited, possibly due to scarcity of these bees. We found that dust from the road …

Diet-Induced Obesity Decreases Liver Iron Stores In Mice Fed Iron Deficient, Adequate, Or Excessive Diets, Brett J. Healy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Epidemiological and observational evidence suggests that obesity is related to poor Fe status. To determine interactions between obesity, dietary Fe intake and Fe status; male, weanling C57BL/6J mice were fed either high fat diets to induce obesity or a standard diet for 16 weeks. Fe concentrations of both the high fat or control diet (4.5 vs 3.8 kcal/g) were set at: 5, 50 or 500 mg Fe/kg diet. Mice fed the high fat diets had significantly higher percentage body fat (17.9%) compared to mice fed control diets (5.3%, P<0.001). Among obese mice, dietary Fe levels did not significantly influence body composition. Conversely among lean mice, mice fed the iron excessive diet had significantly less fat mass when compared to mice fed the iron deficient diet (P<0.05). Obesity and/or dietary Fe concentration did not significantly affect plasma Fe levels. ANOVA analysis showed significant effects of diet-induced obesity, dietary Fe and an interaction between both factors on liver Fe levels (P< 0.05). Obese mice had significantly lowered liver Fe levels compared to lean cohorts fed the same amount of dietary Fe (P<0.05 for all comparisons). Moreover, lean mice fed the Fe deficient diet (5 mg Fe/kg diet) had similar liver Fe levels (127 mg Fe/kg ± 0.04) compared to obese mice fed the 50 mg Fe/kg diet (132 mg Fe/kg ± 0.05). These data suggest that obesity, independent of dietary Fe intake, influences liver Fe stores.

Factors Affecting The Oxidative Stability Of Foods-Interesterified Soybean Oil With High Intensity Ultrasound Treatment And Trona Mineral In Packaged Fresh Meats, Jiwon Lee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Oxidation leads to rancid flavors or odors in oils and meat and causes discoloration in muscle foods. There is a great concern about economic loss when oxidation is not effectively controlled. Novel processing and storage methods such as ultrasound, interesterification, or gas emitter sachet in meat packaging have been studied to provide desirable quality properties of oils and meat products. However, there are not enough studies to explain their effect on oxidative stability. Better understanding of new techniques is required to manage the oxidative stability and even other quality properties.

High intensity ultrasound is an effective method to improve physical …

A Data-Intensive Assessment Of The Species Abundance Distribution, Elita Baldridge

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

One of the most commonly observed patterns in ecology is the fact that at most locations there are a large number of relatively rare species, composed of only a few individuals per species, and a small number of relatively common species. This pattern of commonness and rarity is quantified by the species abundance distribution. As one of the most commonly observed patterns in ecology, it has been studied intensively for over 100 years.

A major emphasis of this research has been developing models to try to understand the forces that generate such a general pattern. As a result, there are …

Evaluating Eriogonum Corymbosum Tolerance To Frequent Irrigation And Evaluating Its Significant Morphological Variations For Potential Cultivars, Graham C. Hunter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Eriogonum corymbosum (Lacy Buckwheat) is an attractive subshrub species native to low rainfall areas of the Colorado Plateau and suitable for low water landscapes in the Intermountain West (IMW). Low water use landscapes can contribute to water conservation in arid climates; developing a palette of plants that are both attractive and drought tolerant can promote the acceptance of low water use landscapes as an alternative to the traditional bluegrass landscapes of the IMW. In 2007 a strip plot design containing four repetitions with four randomly assigned plants each of Eriogonum corymbosum, Eriogonum thompsoniae, and the control species Cornus …

Fatty Acid Induced Insulin Resistance In The Brain, Hyoung Il Oh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The prevalence of obesity is rapidly increasing; it is now one of the most serious public health problems worldwide. Obesity is thought to reflect the interaction between genetics and modern life style. In particular, high fat diets (HFD) are considered as a major contributing factor to the development of obesity and type 2 diabetes as well as other metabolic disorders such as cardiovascular disease, Alzheimer’s disease and some types of cancer. Recently, it has been suggested that insulin actions in the brain are important in the regulation of energy homeostasis and peripheral metabolism.

With the support of USTAR (The Utah …

Peach Fruit Quality Analysis In Relation To Organic And Conventional Cultivation Techniques, Varun Chandra Koneru

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The USA is the third major world producer of peaches but consumption has decreased over the last two decades. Consumers have cited mealy texture, fruit browning and lack of sweetness as some undesirable characteristics in peaches, which may be related to the decline. The focus of this study was to evaluate the effect of farm management practices on fruit quality. Physical parameters (color, firmness and size), volatiles and metabolite data was collected.
Sensory evaluation indicated transitional organic peaches were liked the best and organically grown peaches were least liked. All the treatments were significantly different from each other and consumers …

Effects Of Non-Surface-Disturbing Restoration Treatments On Native Grass Revegetation And Soil Seed Bank Composition In Cheatgrass-Invaded Sagebrush-Steppe Ecosystems, Alexandra D. Reinwald

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The sagebrush-steppe communities of the Great Basin have been dramatically transformed by the invasion of the non-native annual grass cheatgrass. In many areas of the Great Basin, this invasion has resulted in the loss of native plant species and ultimately the conversion to cheatgrass-dominated communities. As healthy sagebrush communities provide multiple ecosystem services such as diverse wildlife habitat, forage for cattle grazing, and water filtration, restoration of these communities is a high priority to landowners and land management agencies. Established perennial grasses can successfully compete with non-native annual grasses and increase the resistance of plant communities to invasion by non-native …