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Greater Sage-Grouse And Community Responses To Strategies To Mitigate Environmental Resistance In An Anthropogenic Altered Sagebrush Landscape, Justin R. Small

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sagebrush (Artemisia spp.) ecosystems are diverse habitats found throughout western North America. Anthropogenic disturbances has resulted in the loss of over half of the sagebrush ecosystems impacting sagebrush obligate species such as sage-grouse (Centrocercus spp.). Federal, state, and private land managers have implemented landscape scale mechanical pinyon (Pinus spp.) and juniper (Juniperus spp.; conifer) removal projects in an effort to restore functioning sagebrush communities to benefit sage-grouse. However, few studies have investigated the potential for using large-scale conifer treatments to mitigate factors impeding sage-grouse seasonal movements and space-use in anthropogenic altered landscapes.

To address this management need, I …

Biomethanation And Alkaline Wet Air Oxidation Of Water Hyacinth (Pontederia Crassipes) From Ozama River, Dominican Republic, Yessica A. Castro

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Obtaining valuable products from environmental remediation waste is a sustainable approach that contributes to the ecological well-being of developing countries. In the present work, the feasibility of the water hyacinth anaerobic digestion as a post-weed management practice in the Ozama River (Dominican Republic) was demonstrated. The estimated energy required for harvesting was lower than that produced during digestion. The biomethanation of water hyacinth was improved by Alkaline Wet Air Oxidation (AWAO), a thermochemical pretreatment process that almost doubled the methane production rate and increased the yield by 24% when conducted at high temperatures. At lower temperatures, the methane yield of …

Substance Misuse Transitions Between Adolescence And Young Adulthood: Impacts On Young Adult Self-Sufficiency, Amanda M. Hagman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Substance misuse during the transition to adulthood can be problematic, but it is also socially celebrated. There can be negative short-term impacts associated with intoxication, but are there negative long-term impacts of substance misuse on the transition into adulthood?

Let us pause for a moment. Many individuals may have just glazed over thinking, “Adulthood? I’m not doing that any time soon.” But when you consider what qualifies individuals as adults, this research may seem more pertinent. Adults make their own choices. Adults take responsibility for those choices. Adults are financially independent. So, while the notion of adulthood may conjure images …

Effect Of Dietary Short And Medium Chain Fatty Acids In Murine Lethal Sepsis Model, David Son Dang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sepsis is defined as the presence of an infection in combination with systemic inflammation in a host. One of the detrimental results of sepsis is multiple organ failure which eventually leads to death. Lipopolysaccharide (LPS), an endotoxin that can be found on the outer surface of gram-negative bacteria, can be used as a model for sepsis. LPS present in the circulatory system of hosts can induce symptoms that are seen in patients during septicemia.

Previous studies have suggested that including milk fat in a diet may protect against a lethal dosage of LPS in rodents. Milk fat has a unique …

Raw Depth Image Enhancement Using A Neural Network, Xuan Xie

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The term image is often used to denote a data format that records information about a scene’s color. This dissertation object focuses on a similar format for recording distance information about a scene, “depth images”. Depth images have been used extensively in consumer-level applications, such as Apple’s Face ID, based on depth images for face recognition.

However, depth images suffer from low precision and high errors, and some post-processing techniques need to be utilized to improve their quality. Deep learning, or neural networks, are frameworks that use a series of hierarchically arranged nonlinear networks to process input data. Although each …

Accounting For Critical Attributes And Uncertainty In Flow-Ecology Relationships, Elizabeth Decker Morgan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Environmental flows are used to maintain streamflow for aquatic species in rivers while also sustaining human water requirements. While there are many approaches to develop environmental flows, they all rely on a strong conceptual understanding of flow-ecology relationships, which are often uncertain. Uncertainty in flow-ecology relationships can stem from using limited data to develop or test relationships or an incomplete understanding of the attributes inherent to each relationship, such as climate and land conditions. Accounting for these attributes and uncertainty in flow-ecology relationships is critical given mounting interest to develop and implement environmental flows at large scales, often with limited …

Trends In Us Crop Yields & Water Use, Britta L. Schumacher

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Over half the land in the US is dedicated to agriculture, with the vast majority of all cropland cultivated in corn, wheat, or soybean. Despite continuing advances in agricultural technologies, and consistent yield growth over the twentieth century, research suggests that environmental change is already impacting agricultural yield and future changes are sure to exacerbate challenges to agricultural production. It follows that the future of US agriculture depends on the evolution of the changing climate, the relationship between crop yields and the environment, on-farm management and adaptations, the ecosystems that support agriculture, the political and economic incentives that shape what …

Socioscientific Issues In School-Based Agricultural Education: Describing And Exploring Factors Of Integration, Michelle S. Burrows

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Socioscientific issues (SSI) are complex issues which are scientific in nature and have societal impacts. Many SSI have connections to agriculture and as such should be included in agricultural education curriculum. A clear understanding of what school-based agricultural education (SBAE) teachers know about SSI is needed. The purpose of this research was to explore the knowledge and integration of SSI among SBAE teachers by describing and explaining the factors that influence integration. This quantitative survey research was guided by the SSI-based instruction framework and the three-component model of agricultural education. The population for this study was all SBAE teachers in …

Monitoring Populations And Movement Of Bobcats (Lynx Rufus) On The Eastern Slope Of The Sierra Nevada Mountains Of California, Michael Brown

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Monitoring the spatial ecology and population densities of carnivores is critical for effective management and conservation of these populations and the ecosystems in which they exist. However, effective monitoring of carnivore populations through estimates of space use, habitat selection and densities can be difficult due to their relatively low densities and wide ranging, elusive behaviors. Bobcats (Lynx rufus) are medium sized, top-level predators which are widely distributed across North America. Quantifying space use, habitat selection and developing effective population monitoring strategies for this species will have important implications for wildlife management.

My first objective was to use telemetry …

Invasive Plant Occurrence Across Agency Boundaries: Two Case Studies From California, Natalie Otto

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Non-native invasive species (NNIS) are a major concern confronting land managers in and surrounding protected areas such as national parks. These areas are managed by a variety of entities, all of which have different mandates, management priorities, and resources that are allocated to NNIS programs. These differences can result in ecological divergences at land boundaries and can create barriers to cooperative management. Through interviews and ecological data collection, this research addresses three topics; 1. It identifies disparities in NNIS and disturbance occurrence between jurisdictions and tests the strength of correlations between these variables; 2. It seeks to determine what role …

Short- And Long-Term Mechanisms For Increasing Inputs Of Phosphorus In Mountain Waterbodies Of Northeastern Utah, Usa, Jessica Scholz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Phosphorus is an essential nutrient that allows life in water to flourish, but changes in phosphorus supplies are not well understood in remote watersheds. In mountain environments, remote watersheds contain critical high-quality water supplies and unique ecosystems, but excess phosphorus can diminish water quality by producing unfavorable aquatic species. Therefore, observed trends of increasing phosphorus concentrations in remote lakes and rivers in the US over the last two decades are a significant concern. Using the Uinta Mountains as a case study, we evaluated three different direct and indirect pathways for phosphorus increases in remote mountain watersheds that may explain observed …

Responses Of Pacific Fishers To Habitat Changes As A Result Of Forestry Practices In Southwestern Oregon, Tessa R. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The fisher (Pekania pennanti) is a medium-sized carnivore found in mature forest stands across much of the northern United States. Although historically abundant in the west, fisher populations declined rapidly after fur trapping, extensive logging, and urban development reduced their numbers. Currently, biologists are concerned about the effects timber harvest practices have on fisher tolerance and adaptability when faced with changes to high-quality habitat stands. Tree removal and thinning of understory vegetation are frequently used to alleviate the spread of wildfires in previously dense forest stands with a potential for large-scale habitat loss; yet, a deficit of large …

Remote Ocean Forcing On Interannual-To-Decadal Climate Variability Through Inter-Basin Interactions, Zachary F. Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation explores the connection between ocean basins through the atmosphere by employing observational data analyses and a climate modeling approach. Sea surface temperature changes in the tropical Pacific, known as the El Niño Southern Oscillation, can influence worldwide weather and sea surface temperatures in other ocean basins. For instance, tropical Pacific sea surface temperatures can impact the Atlantic and Indian Oceans through airflow changes along the equator. However, Atlantic and Indian Ocean sea surface temperature changes can also influence the tropical Pacific through similar processes. Therefore, it is challenging to identify the mechanisms of these remote connections between ocean …

The Velvet Ants (Hymenoptera: Mutillidae): Systematics, Biology, And Biogeography Of A Little-Known Family, George Charles Waldren

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Insects are a ubiquitous and species-rich component of the biologically-diverse planet we inhabit. The majority of insects are understudied, with many species awaiting formal description and their natural history yet to be discovered. Members of the family Mutillidae, commonly known as velvet ants, are one of these little-known insect groups. Velvet ants are technically wasps, and the wingless females superficially resemble true ants of the family Formicidae. Further, they frequently have a ‘velvety’ appearance and are often brightly colored to serve as a warning to would-be predators that they have the ability to inflict a painful sting. These insects are …

An Eulerian Perspective On Spring Migration In Mule Deer, Tatum Del Bosco

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Many herbivores travel between low-elevation winter ranges and high-elevation summer sites. These seasonal movements allow them to avoid deep snow cover, ensure access to favorable habitat, and maximize food intake throughout the year. During the spring season, plants at lower elevations green up earlier at lower elevations than at higher elevations. It has been shown that individual animals will track this vegetation growth during their spring migration, which allows them to maximize forage intake coming out of the nutrient scarce winter. This phenomena has previously been studied by monitoring individual movement trajectories, but it is unknown how this pattern scales …

Investigating Routes And Effects Of Pesticide Exposure On The Blue Orchard Bee (Osmia Lignaria), Andi M. Kopit

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

With native pollinator species on the decline and the honey bee (Apis mellifera L.) industry suffering, it is imperative that we understand the impacts of agricultural practices on pollinators. The blue orchard bee, Osmia lignaria (Megachilidae), is an important alternative pollinator of commercial orchards. Osmia lignaria are solitary, cavity nesting bees with a wide distribution across North America. This species and other solitary, cavity nesting bees experience different routes of pesticide exposure than social pollinators, such as colony-dwelling bumble bees and honey bees. Chapter I focuses on routes of pesticide exposure experienced by cavity-nesting bees, incorporating the relative importance …

Recombinant Piriform Spider Silk Production, Cole R. Peterson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spider silks are remarkable biomaterials, possessing a variety of desirable mechanical and material properties. Humans have long-sought to utilize these materials. Spiders produce a range of different types of silks for different purposes, such as web-building, egg casing, and prey swathing. Because spiders are difficult to farm, a synthetic biological approach must be used to produce silk-like proteins. This research is intended to improve the production of piriform, a specific type of spider silk. This was done with targeted-improvements to microbial metabolism and recovery methodologies. The methods developed in this research are useful for other types of silk production and …

Triggerable, Targetable, And Trackable Flavonol-Based Carbon Monoxide-Releasing Molecules, Livia S. Lazarus

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Long known as a toxic gas, carbon monoxide (CO) has been recently redefined as a health beneficial molecule produced endogenously in humans. The biological activity of CO has been extensively examined in inflammatory conditions, vasoprotection, anti-apoptotic and anticancer studies, although the mechanisms of action are still not well defined. Because CO is a gaseous molecule, a straightforward administration would be inhalation. However, this delivery method is limited to use in hospital settings under professional supervision. For improved control over the amount and location of CO delivery, metal-free and light-triggered carbon monoxide-releasing molecules are of particular current interest. Our lab is …

Laboratory Scale Anaerobic Reactors For Bioenergy From Wastes: Materials, Mathematical Models, And Stoichiometry, Yehor Pererva

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Anaerobic processes are being explored for the production of bioenergy in the form of biomethane and biohydrogen in a "waste-to-value" approach that considers wastes as a resource. Laboratory scale Biomethane potential (BMP) tests and Up-Flow Anaerobic Sludge Blanket (UASB) reactors can be used to indicate the potential recovery of bioenergy from industry wastes. The goals of this research were to: (1) conduct a critical review of models for determining biomethane potential, (2) develop a theoretical relationship for stoichiometry for biomethane and biohydrogen from wastes, and (3) develop key design aspects for geometry and infrastructure, including gas-liquid-solid separation in laboratory UASB …

Nodulation And Growth Of Shepherdia × Utahensis ‘Torrey’, Ji-Jhong Chen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Shepherdia ×utahensis ‘Torrey’ (Elaeagnaceae) is a hybrid of two native actinorhizal plants in the Intermountain West, S. argentea (silver buffaloberry) and S. rotundifolia (roundleaf buffaloberry). Due to actinorhizal symbiosis, atmospheric nitrogen (N₂) can be converted to ammonium, a bioavailable form. Actinorhizal plants have great value in sustainable nursery production and urban landscape use. However, nitrogen fertilizer negatively affects the nodulation of actinorhizal plants. As a newly developed hybrid, both the symbiont identity and nodule formation of S. ×utahensis ‘Torrey’ remain largely unknown. Therefore, experiments were conducted to investigate the nodule formation of S. ×utahensis ‘Torrey’ inoculated with field …

Assessment Of Compost On Dryland Wheat Yield And Quality, Soil Fertility And Water Availability In Utah, Kareem A. Adeleke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In 2014-2016 Kareem Adeleke undertook a graduate project under the supervision of Utah State University (USU) Plants, Soils and Climate professors, Drs. Jennifer Reeve, Astrid Jacobson, and Earl Creech. Organic wheat producers face numerous challenges, such as low soil moisture, soil erosion, and low soil fertility. Organic wheat growers generally do not apply fertilizer due to inability to recoup the costs in the short-term. Compost enhances long-term improvement in soil quality, soil fertility and increase yield in low input environments. Understanding of compost carryover effects in dryland wheat systems is necessary for increased yield that will allow adequate supply of …

Influences Of Forest Edges On The Growth And Health Of Old-Growth Coast Redwood Forests, Cody R. Dangerfield

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Coast redwood (Sequoia sempervirens) is the tallest species in the world, frequently attaining heights greater than 300 ft. The unique characteristics of the redwoods has led to the establishment of several preservation areas including national and state parks. However, abrupt forests edges created by previous logging and landcover changes has left the remaining stands exposed to elevated temperature, sunlight, and wind intensities, thereby making redwoods along the forest edge more susceptible to windthrow and drought stress. Despite the rarity of old-growth coast redwood forests and their ecological and cultural significance, very few studies have investigated how forests edges …

Classification And Prediction Models For Natural Streamflow Regimes In The Arid Southwestern Usa, Angela M. Merritt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding how natural variation in flow regimes influences stream ecosystem structure and function is critical to the development of effective stream management policies and actions. Spatial variation in flow regimes is well understood for stream reaches in mesic regions, but a more robust characterization of flow regimes in arid regions is needed, especially to support biological monitoring and assessment programs. Methods are specifically needed that can accurately predict the flow regime expected at ungauged reaches. We used long-term (41 y) records of mean daily flow from 287 stream reaches in the arid western USA to develop and compare several alternative …

Effect Of Biocrust Development On Establishment Of Native Plants In A Salt Desert System, Merran Owen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Salt desert shrublands are semiarid, shrub-dominated ecosystems that inhabit salt- affected soils. In Great Basin salt deserts, exotic annual plants are invading and displacing native plants. Low plant productivity and slow population growth of native plants in these ecosystems makes them vulnerable to invasion and limits their ability to compete with invasive plants and return to a natural state. Active revegetation efforts, such as planting and direct seeding of native plants, are often unsuccessful for the same reasons. Biological soil crusts (communities of cyanobacteria, lichen, moss, microfungi and other microorganisms that live on the surface layer of the soil) are …

Understanding The Microbial Population Of Lactococcus Lactis. Subsp. Strains During Cheese Making And Initial Storage, Rhitika Poudel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Cheddar cheese is manufactured by fermenting milk with lactic acid bacteria added as Lactococcus lactis. The two major subspecies used are lactis and cremoris. Starter culture for this study was prepared and donated by Vivolac Cultures Corporation, Greenfield, Indiana. Cheddar cheese was made in duplicate using two strains of lactis and cremoris. Milled curd was salted with 2.0, 2.4, 2.8, 3.2 and 3.6% salt, pressed for 3 h and stored at 6¬∞C. The curd was sampled during cheese making and after 6d storage. Two different methods of enumeration were employed. One method involved plate counting which only …

Demographics, Accuracy, And Impact Of Feed Laboratories In The United States, Jerald H. Severe

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Feed analysis is very important to modern society. In the United States feed analysis is used to optimize production of food animals. Feed analysis is also used as a tool to place value on crops. As important as feed analysis is to society, little research has been done that describes which feed laboratories are the most popular and why people use them. It has been thought by some patrons that different results from the same feed sample are obtained by different laboratories. Is this true? If so, what is the effect on those that use feed laboratories to produce animals, …

Collaboration And Reflexivity In Wildland Fire Risk Governance In The Western United States, Brett Alan Miller

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation presents both quantitative and qualitative analysis on different aspects of wildland fire risk management in the western United States. Each of these chapters is framed by and examines the sociological concept of reflexivity, which describes a process of individual and/or collective reflection. This reflexivity is needed to identify and enact alternative management strategies that contend with the expected increases in the number and severity of wildland fires in the future due to the combined effects of even-aged forest growth after years of timber extraction, a legacy of fire suppression, climate change, and increasing human development in the wildland-urban …

Rumen Fermentation Responses To Purified Palmitic, Stearic, Or Oleic Fatty Acids And The Impact Of A Palmitic Acid-Enriched Supplement On Animal Performance, Austin Paul Sears

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Our research examined the responses of palmitic, stearic and oleic fatty acids on neutral detergent fiber (NDF) digestibility and rumen fermentation and the impact of a palmitic acid-enriched supplement on animal performance. In the first research chapter, we evaluated the effect of purified palmitic, stearic, and oleic fatty acids on NDF digestibility and rumen fermentation. Palmitic acid increased NDF digestibility and total production of volatile fatty acids (VFA) compared with oleic acid. Bacterial fatty acid composition was altered by palmitic acid, increasing anteiso-C15:0, C18:2n6 and C18:3n3 fatty acids compared with oleic acid. Compared with control, …

A Systematic Review And Meta-Analysis Of Acceptance And Commitment Therapy In South Korea, Woolee An

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Although psychologists have emphasized the importance of considering clients’ various cultural backgrounds and researching various populations, research is still overly focused on participants from English-speaking countries like the United States and Western countries. Numerous studies evaluating Acceptance and Commitment Therapy (ACT) have been published in South Korea. However, most of the studies are still unknown to English-speaking research communities because of language differences. In order to promote cross-cultural communication of study findings, the current study reviewed treatment research from South Korea.

After searching for Korean ACT studies using Korean electronic databases, 62 studies were selected, and each study’s treatment outcome …

Fruit Tree Responses To Water Stress: Automated Physiological Measurements And Rootstock Responses, William D. Wheeler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

New orchard plantings utilize trees grafted to dwarfing rootstocks planted close together to facilitate larger harvests. These dwarfing rootstocks have not been comprehensively studied for their ability to withstand drought. This is of special importance in the Intermountain West which has limited rainfall. Additionally, orchard growers face competition for water from a growing population and increased uncertainty in rainfall from climate change. My research examined the use of dendrometers, which measure changes in trunk diameter, and sap flow sensors, which measure how quickly sap moves, as methods to inform growers about tree water status. I also used a weighing lysimeter …