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All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

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The Application Of Instructional Design Principles In The Development Of Sportsmanship Education Software And Its Impact On Children’S Acquisition Of Sportsmanlike Attitudes And Behaviors, Michael J. Petersen May 2012

The Application Of Instructional Design Principles In The Development Of Sportsmanship Education Software And Its Impact On Children’S Acquisition Of Sportsmanlike Attitudes And Behaviors, Michael J. Petersen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Millions of people participate in sporting events as either athletes or spectators, or both. The presence or absence of sportsmanship they experience can affect them in both negative and positive ways. The purpose of this study was to determine whether schoolchildren who use a computer-based sportsmanship education program would learn and exhibit more sportsmanship than those who did not use the software. It was determined that younger children were more affected by the software than the older children were.


Assessments Of An Exogenous Proteolytic Enzyme In Beef Steer Diets To Improve Growth Performance And Ruminal Fermentation, Juan Manuel Vera May 2012

Assessments Of An Exogenous Proteolytic Enzyme In Beef Steer Diets To Improve Growth Performance And Ruminal Fermentation, Juan Manuel Vera

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A series of experiments were conducted to investigate the effects of adding an exogenous proteolytic enzyme (EPE) on growth performance and ruminal fermentation characteristics of beef steers fed growing and finishing diets containing 30% dried distillers grains with solubles (DDGS).

In the first experiment, 48 beef steers were divided into two treatments: DDGS diets with and without EPE. Dry matter intake (DMI) was increased (P = 0.02) by the addition of EPE, but neutral detergent fiber (NDF) digestibility was decreased on the growing phase. For the finishing phase, average daily gain ( …


Using Stereo Particle Image Velocimetry To Quantify And Optimize Mixing In An Algae Raceway Using Delta Wings, Blake W. Lance May 2012

Using Stereo Particle Image Velocimetry To Quantify And Optimize Mixing In An Algae Raceway Using Delta Wings, Blake W. Lance

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Biofuel research has been continually growing over the past six decades. Of the potential sources for biofuels, microalgae is the most promising, and circulating (raceway) ponds are the most cost-effective method for growing microalgae in abundance. Nevertheless, biofuel production from algae must be more efficient to be competitive with traditional fuels. Previous studies using several airfoils, triangles, and squares at high angles to the flow direction (angle of attack) show an increase in mixing in raceways and can improve productivity by up to a factor of 2.2. Researchers show that increasing growth by increasing mixing is a repeatable effect that …


The Role Of Fine-Scale Habitat Associations In Structuring Spider Assemblages: Determinants Of Spatial Patterns In Community Composition, Stephanie M. Cobbold May 2012

The Role Of Fine-Scale Habitat Associations In Structuring Spider Assemblages: Determinants Of Spatial Patterns In Community Composition, Stephanie M. Cobbold

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ecologists strive to identify the mechanisms that drive the identity and abundance of species in different locations, because a better understanding of such factors enables them to better predict the effects of habitat modification on organisms, and to identify landscapes in which species are likely to benefit from conservation interventions. However, there is still no consensus on the mechanisms behind geographical variation in species diversity. The primary objective of this dissertation was to focus on spider assemblages to investigate how the fine-scale habitat associations of organisms may drive the composition of their communities at larger scales. Research was conducted in …


The Effects Of 24r, 25-Dihydroxyvitamin D3 And 24s, 25-Dihydroxyvitamin D3 On Phosphate Transport In Vivo, Yu Meng Dec 2011

The Effects Of 24r, 25-Dihydroxyvitamin D3 And 24s, 25-Dihydroxyvitamin D3 On Phosphate Transport In Vivo, Yu Meng

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research studied the effects of the two isomers of 24,25(OH)2D3 on phosphate absorption in vivo to increase our understanding of the effects of 24,25(OH)2D3 on phosphate transport in vivo, and its two isomers. The current work demonstrates that 24R,25(OH)2D3 is capable of decreasing phosphate absorption after a 1h injection in vivo and 24S,25(OH)2D3 can increase phosphate absorption after a 5h injection, but this stimulation disappears at time points after 5h.

Since 24,25(OH)2D3 is made in vitamin D-replete animals, the observation that 24R,25(OH)2D …


Rotating Algal Biofilm Reactors: Mathematical Modeling And Lipid Production, Paul A. Woolsey Dec 2011

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 …


Does Non-Steroidal Anti-Inflammatory Drug (Nsaid) Use Affect Dementia Progression And Survival Rates In Alzheimer's Disease? The Cache County Study, Trevor R. Buckley Dec 2011

Does Non-Steroidal Anti-Inflammatory Drug (Nsaid) Use Affect Dementia Progression And Survival Rates In Alzheimer's Disease? The Cache County Study, Trevor R. Buckley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Alzheimer's disease (AD) has multiple factors that contribute to the disease process. Among these is a state of chronic inflammation that is endured by the brain during the aging process. The use of non-steroidal anti-inflammatory drugs (NSAIDs) decreases the amount of neuroinflammation sustained by the brain, and greater levels of NSAID use have been demonstrated to be associated with decreased probability of developing AD. This study looked at whether greater rates of NSAID use were also associated with decreased rates of cognitive and funtional decline and survival in a population-based sample of persons with AD. Linear mixed models failed to …


Outcomes Of Rotator Cuff Surgery In Utah Workers’ Compensation Patients, Jennifer R. Grewe Dec 2011

Outcomes Of Rotator Cuff Surgery In Utah Workers’ Compensation Patients, Jennifer R. Grewe

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The rotator cuff is responsible for the lifting function of the shoulder and the circular movement of the arm. Rotator cuff injuries are the most common problem for the shoulder and account for approximately 4.1 million annual physicians visits. Approximately 20.7% of the population has at least one rotator cuff tear and more than 75,000 individuals will have rotator cuff surgery each year. Medical and compensation costs associated with a rotator cuff surgery are increasing and current estimated annual costs exceed 2 billion dollars. The increasing prevalence and cost associated with rotator cuff injuries in the United States population represents …


Effects Of Tannin-Containing Feed On Haemonchous Contortus In Sheep And Its Behavioral Implications, Jessica A. Juhnke Dec 2011

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 …


Molecular Interactions Of Salmonella With The Host Epithelium In Presence Of Commensals, Prerak T. Desai Dec 2011

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 …


Have Introduced Brown Trout (Salmo Trutta) Affected Native Aquatic Vertebrates In Western United States Streams?, Nora K. Burbank Dec 2011

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 …


Class-Wide Respect And Social Support Skill Training To Increase Peer Interactions Of Students With Autism Spectrum Disorders, Melanie Orton Dec 2011

Class-Wide Respect And Social Support Skill Training To Increase Peer Interactions Of Students With Autism Spectrum Disorders, Melanie Orton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The demand for effective social skills interventions for children with autism spectrum disorders is a pertinent issue for school-based professionals. One approach to increase appropriate social skills is to involve peer support by training a few socially competent children to positively interact with a student with an ASD. Potentially, training larger groups of children could result in increasing the number of different peers who would actively support positive interactions with their classmates with ASD. Thus, the present study investigated the effect of a class-wide peer-training strategy on the percentage of positive social interaction and number of peer contacts for three …


Fish Passage Through Rehabilitated Culverts Laboratory Study, Amber H. Olsen Dec 2011

Fish Passage Through Rehabilitated Culverts Laboratory Study, Amber H. Olsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Slip lining culverts represent a low-cost technique that can restore life to decaying culverts. However, slip liners are smoother than typical host culverts; therefore, they generate higher flow velocities and lower flow depths within the culvert, which are fish passage barriers. One way to mitigate these barriers is by installing baffles. Unfortunately baffles can jeopardize the flow capacity of the culvert.

The Utah Water Research Laboratory (UWRL) at Utah State University contracted with the Utah Department of Transportation for $85,000 to test the effectiveness of baffles in improving fish passage through culverts. The goal of this project was to identify …


The Potential For Growth In Foreign Direct Investment In The Horticultural Sector Of Armenia, Mikayel Khachatryan Dec 2011

The Potential For Growth In Foreign Direct Investment In The Horticultural Sector Of Armenia, Mikayel Khachatryan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examines why foreign investors choose to invest in companies in Armenia and is specifically attempting to understand how to attract more investment into the fruit and vegetable companies of Armenia. Investment by foreigners in domestic companies is referred to as foreign direct investment of FDI. The research was completed by gathering information from foreign firms that are already investing in companies in Armenia. This was done by conducting a face-to-face questionnaire with business managers of these companies in Yerevan, Armenia during August and December of 2010. The information gathered from these interviews was used in a statistical analysis …


Assessment Of Colorado’S Wilderness Areas: Manager Perceptions And Remoteness Modeling, Gary D. Vaughn Dec 2011

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 …


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 Dec 2011

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 Dec 2011

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 …


Accelerating Production Of Slow-Growing Intermountain West Native Plants By Modifying Their Microclimate, Sam A. Miller Dec 2011

Accelerating Production Of Slow-Growing Intermountain West Native Plants By Modifying Their Microclimate, Sam A. Miller

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Water shortages are a recurring problem in the western US. As much as 70% of yearly municipal water consumption may be used to irrigate urban landscapes. Significant water savings can be realized by installing low water landscapes, where turfgrass is replaced by low water trees, shrubs, grasses, and perennials. Intermountain West (IMW) native trees and shrubs are excellent candidates for low water landscaping. However, due to their slow initial growth, many native trees and shrubs are simply unavailable to consumers, as they are not cost effective for nursery growers to produce. In an effort to accelerate the yearly growth rates …


Effect Of Voluntary Exercise And Diet On The Unfolded Protein Response In The Brain Of Mice, Yu Ho Kim Dec 2011

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 Dec 2011

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, …


Analysis Of The Import, Export, And Bioavailability Of Nitrogen And Phosphorus Within Pineview Reservoir, Brady K. Worwood Dec 2011

Analysis Of The Import, Export, And Bioavailability Of Nitrogen And Phosphorus Within Pineview Reservoir, Brady K. Worwood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was conducted to provide new and useful data about Pineview Reservoir and its watershed, produce water and phosphorus (P) budgets for Pineview Reservoir, test the validity of conclusions made in the Pineview Reservoir Total Maximum Daily Loading (TMDL) document, and create estimates of nitrogen (N) loading to the reservoir from both surface and ground water sources. The production of the water and P budgets, as well as the N loading estimates, was accomplished by measuring flow, nitrate, ammonium, total phosphorus (TP), and soluble reactive phosphorus (SRP) that was entering and exiting the reservoir through surface water sources and …


Seasonal Transport Of Suspended Solids And Nutrients Between Bear River And Bear Lake, Cody M. Allen Dec 2011

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 Dec 2011

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 …


Zeolite‐Based Algae Biofilm Rotating Photobioreactor For Algae And Biomass Production, Ashton M. Young Aug 2011

Zeolite‐Based Algae Biofilm Rotating Photobioreactor For Algae And Biomass Production, Ashton M. Young

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Alkaline conditions induced by algae growth in wastewater stabilization ponds create deprotonated ammonium ions that result in ammonia gas (NH3) volatilization. If algae are utilized to remediate wastewater through uptake of phosphorus, the resulting nitrogen loss will hinder this process because algae generally require a stoichiometric molar ratio of N16P1. Lower ratios of N/P due to loss of ammonia gas will limit the growth and yield of algae, and therefore will reduce phosphorus removal from the water phase into the algae phase. In order to reduce nitrogen loss through volatilization, an ammonium selective zeolite, …


Going Solo With Roald Dahl: Life Rewritten Through Memory, Jeannine Huenemann Aug 2011

Going Solo With Roald Dahl: Life Rewritten Through Memory, Jeannine Huenemann

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Roald Dahl does not easily fit into a category as a writer, contributing fiction and nonfiction to both children and adult audiences. Faced with this ambiguity, the literary community has mostly ignored his contributions since he is mainly viewed as a children‘s author. Late in life, Dahl created two autobiographies, Boy: Tales of Childhood (1984), and Going Solo (1986), as venues for sharing his many embellished, personal stories. This thesis focuses on Going Solo, the second of these two books which explores Dahl‘s three-year departure from England, including his enlistment in the Royal Air Force during World War II. …


Effect Of Adjunct Cultures, Sodium Gluconate, And Ripening Temperature On Low-Fat Cheddar Cheese Flavor, Rebekah M. Lance Aug 2011

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 …


Evaluation Of Levulinic Acid For Topical Decontamination Of Meat Surfaces, Jeffrey V. Smith Aug 2011

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, …


Burmese Muslim Refugee Women: Stories Of Civil War, Refugee Camps And New Americans, Karen Hunt Lambert Aug 2011

Burmese Muslim Refugee Women: Stories Of Civil War, Refugee Camps And New Americans, Karen Hunt Lambert

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis includes the narratives of three Burmese Muslim refugee mothers who made their homes in Logan, Utah, within three years of locating in the United States. Each woman’s life is written about in a different style of writing – journalism, ethnography and creative nonfiction –and is then followed by analysis looking at each piece in terms of representation


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 Aug 2011

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 …


Ecologically-Based Manipulation Practices For Managing Bromus Tectorum-Infested Rangelands, Beth Fowers Aug 2011

Ecologically-Based Manipulation Practices For Managing Bromus Tectorum-Infested Rangelands, Beth Fowers

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Cheatgrass (Bromus tectorum) is an invasive annual grass common in several semiarid plant communities in the western U.S. B. tectorum presence increases fire frequency and size, reducing species diversity, and leading to annual species-dominated systems with inconsistent livestock forage potential and degraded wildlife habitat value. Most efforts to manage B. tectorum-dominated rangelands have focused on controlling the plant itself rather than addressing the causes of vegetation change. An alternative approach, ecologically-based invasive plant management (EBIPM), identifies treatments that can alter factors associated with the causes of succession, leading to a more desirable vegetation state. This study utilized …