Life Sciences Commons^™

Molecular Interactions Of Salmonella With The Host Epithelium In Presence Of Commensals, Prerak T. Desai

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Food-borne infections are a major source of mortality and morbidity. Salmonella causes the highest number of Food-borne bacterial infections in the US. This work contributes towards developing strategies to control Salmonella by (a) defining receptors used by Salmonella to adhere to and invade the host epithelium; (b) developing a host receptor based rapid detection method for the pathogen in food matrix; (C) and defining mechanisms of how probiotics can help alleviate Salmonella-induced cell death in the host epithelium.

We developed a cell-cell crosslinking method to discover host-microbe receptors, and discovered three new receptor-ligand interactions. Interaction of Salmonella Ef-Tu with …

Effects Of Tannin-Containing Feed On Haemonchous Contortus In Sheep And Its Behavioral Implications, Jessica A. Juhnke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Herbivores prefer foods that supply required nutrients and avoid those with excess nutrients and plant secondary compounds (PSC). Nevertheless, PSC such as condensed tannins can provide beneficial medicinal effects to herbivores. The objectives of this study were to determine: 1) if parasitized lambs increased preference for a tannin-rich food after they experienced the beneficial antiparasitic effects of tannins relative to parasitized lambs that did not experience such benefits, 2) if preference for the tannin-containing food in the former group decreased when parasite burdens subsided, and 3) if the tannin-enriched food decreased parasitic burdens.

Twenty-two lambs were familiarized with beet pulp …

Have Introduced Brown Trout (Salmo Trutta) Affected Native Aquatic Vertebrates In Western United States Streams?, Nora K. Burbank

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The introduction of exotic species to areas outside of their native range is one of the greatest threats to the biodiversity of native freshwater organisms. Exotic species have outcompeted native species for resources such as food and shelter, and in some cases these interactions have resulted in local extinctions or reductions in abundance of those native species. Brown trout are native to Eurasia, but have been introduced to much of the rest of the world, including the United States. In some parts of their introduced range, brown trout have substantially reduced the abundance and home ranges of some native fish …

Characterizing Water And Nitrogen Dynamics In Urban/Suburban Landscapes, Hongyan Sun

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research investigated the water use of different plant types in urban landscapes, nitrogen (N) and water transport in turf, and potential N leaching from urban landscapes to ground water. In the first study, three landscape treatments integrating different types of plants—woody, herbaceous perennial, turf—and putative water use classifications—Mesic, Mixed, Xeric—were grown in large drainage lysimeters. Each landscape plot was divided into woody, turf, and herbaceous perennial plant hydrozones and irrigated for optimum water status over two years, with water use measured using a water balance approach. For woody plants and herbaceous perennials, canopy cover, rather than plant type or …

Isotopic Tracer Reveals Depth-Specific Water Use Patterns Between Two Adjacent Native And Non-Native Plant Communities, Clémence Pascale Warren

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Non-native plants have invaded over 100 millions of acres of western arid land in the US and dramatically altered nutrient cycling rates. Changes in water cycling caused by invasive species are of particular interest because primary production in the Western US is typically limited by water availability and aquifer recharge reflects plant demand. Large-scale invasions can, therefore, be expected to cause large-scale changes in hydrological cycles, but until recently, there have been considerable limitations in the ability to measure the timing, location, and extent of water use. Here we injected a tracer, deuterated water (D₂O), into five soil …

Relative Importance Of Environmental Variables For Spawning Cues And Tributary Use By An Adfluvial Lake Sucker, Brian A. Hines

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The endangered June sucker (Chasmistes liorus mictus), which is only found in Utah Lake, UT, historically spawned in all streams flowing into the lake, but due to human-caused changes their spawning is restricted to the Provo River. The purpose of this study was to gain a better understanding of the spawning and early life-history of the
June sucker for recovery purposes. My specific objectives were to determine:

1. what environmental factors attract or deter June suckers to certain Utah Lake tributaries for spawning,
2. what cues June suckers to migrate upstream to spawn,
3. if June suckers use more than one …

An Assessment Of Vegetation Metrics And Plot Types To Measure Seasonal Variation And Grazing Effects On Riparian Plant Communities, Caroline M. Laine

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Monitoring changes in vegetation is important on public lands. Observing how plant communities respond to changes in land management can give insightful information about which management practices are sustainable. Because water is scarce in the western United States, many land managers focus their monitoring efforts along streams. However, monitoring streamside vegetation is challenging due to a variety of factors and can be confounded by factors such as seasonal climate variation and management activities, like cattle grazing.

In vegetation assessment, there are a variety of measurements that are taken to glean valuable information. Some attributes of interest include how much vegetation …

Analysis Of Food Web Effects Of Non-Native Fishes And Evaluation Of Stream Restoration Potential For The San Rafael River, Utah, Timothy E. Walsworth

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Native fishes of the Colorado River Basin have experienced dramatic reductions in range and abundance as a result of extensive human alterations to the basin’s waterways. Many of these native fishes are federally listed under the Endangered Species Act, while several others are subject to range-wide conservation agreements between state and federal management agencies. Three of the native species subject to range-wide conservation agreements are the flannelmouth sucker, bluehead sucker, and roundtail chub (hereafter, the “three species”). Each of the “three species” is still found in the San Rafael River of southeastern Utah, which has experienced habitat degradation and non-native …

Assessment Of Colorado’S Wilderness Areas: Manager Perceptions And Remoteness Modeling, Gary D. Vaughn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study assessed visitor use levels and resource and social conditions in wilderness areas across the State of Colorado using existing and collected spatial data. This is the first attempt to spatially assess wilderness conditions at the state level. A state-wide assessment of wilderness conditions allows local and regional managers to make informed regional decisions and to prioritize and direct their time and energy efficiently. This assessment clarifies the recreational use and impacts across the state. This study consists of two projects: 1) managers’ perceptions of the location and extent of resource and social condition problems; and 2) a geographic …

Orchard Floor Management, Marc A. Rowley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Managing fruit orchards involves both the management of the orchard trees, and the orchard floor. Orchard floor management is vital to tree health, yield and fruit quality. Current standard management practices include maintaining a vegetation free tree row and a grass-covered alleyway. This system effectively controls weeds and creates a favorable environment for the fruit trees. However, limitations to standard orchard floor practices are that the grass alleyway provides no nutrient benefit, and current practices do not readily lend themselves to organic management. Alternative in-row and alleyway systems are requisite to creating improved orchard floor management systems.

Three different approaches …

Using Species Distribution Models To Assess Invasion Theory And Provide Management Recommendations For Riparian Areas In The Eastern Columbia And Western Missouri River Basins, Diane R. Menuz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Globalization has created opportunities for plant and animal species to be transported to novel ecosystems. A subset of these species become invasive species, which are able to persist and spread rapidly to become influential components in their new ecosystems. Invasive species are often able to out-compete co-occurring native species and can alter fundamental ecosystem properties, such as soil nutrient availability or time between wildfires in a region. The United States is estimated to lose $34 billion per year to invasive plant species through costs to control unwanted species and lowered crop and forage production.

We used statistical models to better …

Reconstructing The Holocene Arroyo History Of The Upper Escalante River, Southern Utah, Using Optically Stimulated Luminescence (Osl) And Radiocarbon Dating, Anne E. Hayden

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Arroyos are steep-walled, entrenched, typically ephemeral streams commonly found in dryland river systems that form when streams incise into previously deposited alluvial fill. Arroyos in the southwestern U.S. have been studied extensively following the historic period of arroyo cutting in the late 1800s and early 1900s A.D. The upper Escalante River in south-central Utah similarly began incising in 1909, and records evidence for past cut and fill cycles in well-exposed walls along the now continuous arroyo.

Establishing robust geochronologies of past arroyo cycles in these fluvial settings has been difficult. Recent improvements in accelerator mass spectrometry (AMS) radiocarbon (^{14 …}

Effect Of Voluntary Exercise And Diet On The Unfolded Protein Response In The Brain Of Mice, Yu Ho Kim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The medical costs for many chronic diseases are increasing dramatically and placing a major financial burden on nations and individuals in both developed and developing countries. A number of chronic diseases, such as obesity, type 2 diabetes and some neurodegenerative diseases are all attenuated by a history of physical activity suggesting that they may be interconnected in some way. It has been suggested that cellular stress is a major factor promoting these chronic diseases.

Cellular stress occurs in a specific compartment within the cell, the endoplasmic reticulum, whose normal function is in the synthesis and folding of proteins into the …

The Biogeography Of Marbled Godwit (Limosa Fedoa) Populations In North America, Bridget E. Olson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The mission of the U.S. Fish and Wildlife Service (USFWS) is working with others to conserve, protect, and enhance fish, wildlife, plants, and their habitats for the continuing benefit of the American people. Toward fulfillment of that mission, a priority of the USFWS is conservation and management of migratory birds. Effective conservation actions to ensure the continued existence of a species on the landscape cannot be designed without first understanding basic life history characteristics of a species. It is common in the case of migratory birds, that we lack understanding of some of their elemental biological traits.

The Marbled Godwit, …

Causes And Consequences Of Plant Spatial Patterns On Natural And Experimental Great Basin (Usa) Plant Communities, Andrew P. Rayburn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The processes by which plant spatial patterns are formed, and the effects of those patterns on plant community dynamics, remain important areas of research in plant ecology. Plant spatial pattern formation has been linked to many ecological processes that act to structure plant communities at different spatiotemporal scales. Past studies of pattern formation are common, but recent methodological advances in data collection and analysis have permitted researchers to conduct more advanced observational studies of pattern formation in space and time. While studies of the effects of plant spatial patterns were formally rare, they have increased in the last decade as …

Rotating Algal Biofilm Reactors: Mathematical Modeling And Lipid Production, Paul A. Woolsey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Harvesting of algal biomass presents a large barrier to the success of biofuels made from algae feedstock. Small cell sizes coupled with dilute concentrations of biomass in lagoon systems make separation an expensive and energy intense-process. The rotating algal biofilm reactor (RABR) has been developed at USU to provide a sustainable technology solution to this issue. Algae cells grown as a biofilm are concentrated in one location for ease of harvesting of high density biomass. A mathematical model of this biofilm system was developed based on data generated from three pilot scale reactors at the City of Logan, Utah wastewater …

Seasonal Transport Of Suspended Solids And Nutrients Between Bear River And Bear Lake, Cody M. Allen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I measured inflows and outflows of nutrients and suspended solid through the wetland complex, known as Dingle Marsh, at the Bear River Migratory Bird Refuge between October 2007 and September 2008. My analysis of changes throughout the year will help Dingle Marsh managers adjust the timing and volume of water movement between Bear River and Bear Lake to meet defined refuge goals, such as improving bird or other animal habitat. These results could also be used to protect Bear Lake’s water quality.

Automated samplers took readings of dissolved oxygen, turbidity, pH and water temperature every 30 minutes. These values were …

Genetic Status Of Isolated Populations Of Colorado River Cutthroat Trout (Oncorhynchus Clarkii Pleuriticus) In The North Fork Little Snake River Drainage, Wyoming, Rachel Van Horne

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Over the last century native cutthroat trout populations have declined in the western United States. Habitat fragmentation is one of the main causes for this decline. Human actions such as the construction of roads, weirs, dams, and water diversions intersect streams and prevent the natural movement of fish. In many cases native cutthroat trout are now confined to headwater streams above human-created barriers. These barriers not only fragment the populations but also increase the risk of individual population extinction.

This study established a baseline genetic structure for nine isolated populations of Colorado River cutthroat trout in the North Fork Little …

Effects Of Supplementing Propionibacteria In Lactation Dairy Diets On Ruminal Fermentation In Continuous Cultures, Karmella Ann Dolecheck

Undergraduate Honors Capstone Projects

The aim of the present study was to assess characteristics of in vitro ruminal fermentation when mixed cultures were offered lactation dairy diets supplemented with the direct-fed microorganism, Propionibacterium P63 in continuous cultures. The design of the experiment was a 2 × 2 factorial with 4 replications. Diets based on corn silage and alfalfa hay as the forage sources were formulated; high forage (HF) or low forage (LF) diet with a forage-to-concentrate ratio of 60:40 or 40:60 (DM basis), respectively, was combined without or with P63 to form 4 treatments: HF without P63, HF with P63, LF without P63, and …

Evaluation Of Levulinic Acid For Topical Decontamination Of Meat Surfaces, Jeffrey V. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Experiments were performed to investigate the effects of wash treatments, consisting of hot water, 2% lactic, 2% acetic, or 2% levulinic acid, for decontamination of pathogenic bacteria previously inoculated onto meat surfaces, to inhibit growth of pathogenic bacteria inoculated onto previously washed meat surfaces, and on the organoleptic quality of sliced turkey roll and beef trim. Acid washes were no more effective at reducing Escherichia coli O157:H7 on beef plate, Listeria monocytogenes on sliced turkey roll, and Salmonella on pork belly than was water wash. Only lactic acid treatment was more effective than water at reducing Salmonella on chicken skin, …

Characterization Of Volatile And Metabolite Compounds Produced By Lactococcus Lactis In Low-Fat And Full-Fat Cheddar Cheese Extract, Michael J. Young

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was conducted to compare and contrast potential aroma compounds in the headspace and small molecule metabolites produced as a result of starter culture metabolism in a full-fat and low-fat cheddar cheese model system. Past studies have indicated differences in the headspace flavor compound profiles between full-fat and low-fat Cheddar cheeses with no indication as to what compounds were produced as a result of starter culture metabolism.

Starter cultures were incubated in a Cheddar cheese extract environment that was made up of the water-soluble portion of Cheddar cheese with environmental conditions mimicking full-fat and low-fat Cheddar cheese by altering …

Studies Of The Distinguishing Features Of Nadph:2-Ketopropyl-Coenzyme M Oxidoreductase/Carboxylase, An Atypical Member Of The Disulfide/ Oxidoreductase Family Of Enzymes, Melissa A. Beighley-Kofoed

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The metabolism of propylene in Xanthobacter autotrophicus occurs via epoxypropane formation and subsequent metabolism by a three-step, four-enzyme pathway, utilizing the atypical cofactor Coenzyme M (CoM) to form acetoacetate. The last step in the epoxide carboxylase pathway is catalyzed by a distinctive member of the disulfide oxidoreductase (DSOR) family of enzymes, NADPH:2-ketopropyl CoM oxidoreductase/carboxylase (2-KPCC). 2-KPCC catalyzes the unorthodox cleavage of a thioether bond and successive carboxylation of the substrate. The focus of the research presented in this dissertation aims to elucidate the details of 2-KPCC that allow it to perform chemistry unconventional for typical DSOR members. Sitedirected mutagenesis was …

Effect Of Adjunct Cultures, Sodium Gluconate, And Ripening Temperature On Low-Fat Cheddar Cheese Flavor, Rebekah M. Lance

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Low-fat Cheddar cheese flavor is different from full-fat Cheddar cheese and is not acceptable to many consumers. This 2-part experiment was designed to examine effects adjunct cultures have on low-fat Cheddar cheese flavor as determined through descriptive analysis and consumer feedback.

In Part 1, low-fat (5%) Cheddar cheese was produced in duplicate, using 6 combinations of DVS850, LH32, CR540, CRL431, Emfour, and CR319 bacterial cultures. Due to a previously observed positive effect by sodium gluconate on low-fat cheese flavor, each replicate was split into treatments of 0.0% and 0.8% sodium gluconate. Each of these treatments was then split into ripening …

Community Level Effects Of Vegetation Architecture And Prey Availability: A Study Of Ground-Dwelling Arthropods In A Shrub-Steppe Ecosystem, Mary E. Pendergast

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Changes to vegetation architecture within a natural habitat can have profound impacts upon ecological community function, but the relative influence of vegetation architecture itself and potential indirect influences of associated food resources are often difficult to disentangle. I present the results of a three-year study designed to address the community level impacts of changes in big sagebrush (Artemisia tridentata) architecture and associated prey availability upon the ground-dwelling arthropod community. Three experimental sagebrush architecture treatments (low, intermediate, and high foliage density) and two levels of prey insect availability treatment (natural and baited/increased prey availability) were imposed in a sage-steppe …

The Decline And Conservation Status Of North American Bumble Bees, Jonathan B. Koch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Several reports of North American bumble bee (Bombus Latreille) decline have been documented across the continent, but no study has fully assessed the geographic scope of decline. In this study I discuss the importance of Natural History Collections (NHC) in estimating historic bumble bee distributions and abundances, as well as in informing current surveys. To estimate changes in distribution and relative abundance I compare historic data assembled from a >73,000 specimen database with a contemporary 3-year survey of North American bumble bees across 382 locations in the contiguous U.S.A. Based on my results, four historically abundant bumble bees, B. …

Effects Of Non‐Surface‐Disturbing Treatments For Native Grass Revegetation On Cheatgrass (Bromus Tectorum L.) Metrics And Soil Ion Availabilities, Jan C.R. Summerhays

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Several restoration methods intended to increase the success of aerially‐seeded perennial grasses were assessed to determine their effects on cheatgrass metrics and soil nutrient bioavailabilities. These methods were: 1) imazapic herbicide application (140 g ai ∙ ha^-1, 210 g ai ∙ ha^-1, and no application [control]), 2) vegetation manipulation treatments (50% sagebrush overstory thinning, 100% sagebrush overstory thinning, sagebrush overstory and/or vegetative thatch burning, and no manipulation [control]), and 3) alternative seeding treatments (aerial seeding with raking, aerial seeding with activated carbon [AC] addition, aerial seeding with sucrose addition, and regular aerial seeding [control]). Treatments were …

A Sensory-Based Multi-Component School-Based Nutrition Intervention Among Fifth-Grade Students, Stacy Lyn Bevan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The nutritional status of children is declining as evidenced by the steady rise in childhood obesity rates over the last three decades. Consuming five servings of fruit and vegetables (FV) daily has shown to help with weight maintenance, but children are consuming far less than the recommended servings. This study was designed to test the efficacy of a sensory-focused multi-component school-based program at increasing vegetable intake among fifth-graders. Classroom, family, and community components allowed children to explore thirteen target vegetables with their senses including taste. Vegetable consumption was measured by digitalized observations of lunchtime vegetable selection and consumption. Vegetable acceptance …

Ungulate Damage To Safflower In San Juan County, Utah, Michael J. Haney

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In Utah, farmers are concerned that ungulates are damaging safflower (Carthamus tinctorius) fields. I examined elk (Cervus elaphus) and mule deer (Odocoileus hemionus) damage to safflower production in San Juan County, Utah during 2009 and 2010. Data on damaged safflower plants were collected within 28 fields, totaling 1,581 ha (13 fields totaling 963 ha during 2009; 15 fields totaling 618 ha during 2010). I compared 3 methods to assess losses: ungulate-proof exclosures, adjacent plant compensation method, and counting the number of damaged plants in 50-m transects (safflower count method). Exclosures were of limited use …

Reducing Reliance On Supplemental Winter Feeding In Elk (Cervus Canadensis): An Applied Management Experiment At Deseret Land And Livestock Ranch, Utah, Dax L. Mangus

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wildlife managers have fed elk in North America for nearly 100 years. Giving winter feed to elk can compensate for a shortage of natural winter range and may boost elk populations while also helping prevent commingling with livestock and depredation of winter feed intended for livestock. In contrast to these benefits of supplemental feeding, there are economic and environmental costs associated with feeding, and elk herds that winter on feeding grounds have a higher risk of contracting and transmitting disease. Brucellosis is of primary concern now, and Chronic Wasting Disease may be in the future. Many see the discontinuation of …

Climate Change And Community Dynamics: A Hierarchical Bayesian Model Of Resource-Driven Changes In A Desert Rodent Community, Glenda M. Yenni

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Predicting effects of climate change on species persistence often assumes that those species are responding to abiotic effects alone. However, biotic interactions between community members may affect species’ ability to respond to abiotic changes. Latent Gaussian models of resource availability using precipitation and NDVI and accounting for spatial autocorrelation and rodent group-level uncertainty in the process are developed to detect differences in seasons, groups, and the experimental removal of one group. Precipitation and NDVI have overall positive effects on rodent energy use as expected, but meaningful differences were detected. Differences in the importance of seasonality when the dominant group was …