Life Sciences Commons^™

Identifying And Understanding The Spatial Distribution Of Bobcat And Coyote Behavior, Ryan Radford Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A common observation in animal space use studies is that animals do not use space uniformly, but rather use some areas of their home ranges and territories with much higher intensity than others. Numerous methods have been developed to estimate these "core areas"; however, all of the current methods available are based on arbitrary rules. Additionally, most studies do not attempt to understand what behavioral processes lead to the observed patterns of non-uniform space use. This study has four main objectives: 1) to develop an objective and more precise method for estimating core areas, 2) to understand the processes leading …

Evaluating Native Wheatgrasses For Restoration Of Sagebrush Steppes, Jayanti Ray Mukherjee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pseudoroegneria spicata and Elymus wawawaiensis are two native perennial bunchgrasses of North America's Intermountain West. Frequent drought, past overgrazing practices, subsequent weed invasions, and increased wildfire frequency have combined to severely degrade natural landscapes in the region, leading to a decline in the abundance of native vegetation. Being formerly widespread throughout the region, P. spicata is a favorite for restoration purposes in the Intermountain West. Elymus wawawaiensis, which occupies a more restricted distribution in the Intermountain West, is often used as a restoration surrogate for P. spicata. However, since most restoration sites are outside the native range of …

Genomic Perspectives On Evolution In Bracken Fern, Joshua P. Der

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The fern genus Pteridium comprises a number of closely related species distributed throughout the world. Collectively they are called bracken ferns and have historically been treated as a single species, Pteridium aquilinum. Bracken is notorious as a toxic weed that colonizes open fields and poisons livestock. Bracken is also easily cultured and has become one of the most intensively studied ferns. Bracken has been used as a model system for the study of the fern life cycle, fern gametophyte development, the pheromonal mechanism of sex determination, toxicology, invasion ecology, and climate change. This dissertation places bracken within a global …

A Synthetic Biological Engineering Approach To Secretion- Based Recovery Of Polyhydroxyalkanoates And Other Cellular Products, Elisabeth Linton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The costs associated with cellular product recovery commonly account for as much as 80% of the total production expense. As a specific example, significant recovery costs limit commercial use of polyhydroxyalkanoates (PHA), which comprise a class of microbially-accumulated polyesters. PHAs are biodegradable compounds that are of interest as a sustainable alternative to petrochemically-derived plastics. Secretion-based recovery of PHAs was studied to decrease PHA production costs. Type I and II secretory pathways are commonly used for the translocation of recombinant proteins out of the cytoplasm of E. coli. Proteins were targeted for translocation using four signal peptides (HlyA, TorA, GeneIII, …

Greater Sage-Grouse Response To Sagebrush Reduction Treatments In Rich County, Utah, Roger Blair Stringham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Management of greater sage-grouse (Centrocercus urophasianus) in the west has changed over the last several decades in response to environmental and anthropogenic causes. Many land and wildlife management agencies have begun manipulating sagebrush with herbicides, machinery, and fire. The intent of these manipulations (treatments) is to reduce sagebrush canopy cover and increase the density of grass and forb species, thus providing higher quality sage-grouse brood-rearing habitat. However, monitoring of sage-grouse response to such manipulations has often been lacking or non-existent. The objective of our study was to determine the response of sage-grouse to sagebrush reduction treatments that have …

Natural History And Breeding System Of Maguire Primrose, Jacob B. Davidson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The goal of this thesis was to examine the breeding system and natural history of the Maguire primrose (Primula cusickiana var. maguirei). Maguire primrose is an endemic, threatened subspecies found only along a narrow corridor within Logan Canyon in northern Utah, USA. This plant displays distinct flower distyly, with clear distinction of pin and thrum morphologies (morphs). The timing of Maguire primrose flower blooms was disparate between upper and lower canyon populations, and the flowers experienced cool temperatures occasionally. I captured eight different species of flying insects visiting Maguire primrose flowers, and made 67 observations of insect visitation. …

The Effect Of In-Line Lakes On Dissolved Organic Matter Dynamics In Mountain Streams, Keli J. Goodman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research combines observation, experimentation, and modeling to evaluate the influence of lakes on dissolved organic matter (DOM) quantity, quality and export in subalpine watersheds of the Sawtooth Mountain Lake District, central Idaho.

First, I conducted an empirical study of the hydrologic and biogeochemical controls on DOM dynamics in stream-lake fluvial networks. I hypothesized that lakes would decrease temporal variability (i.e., buffer) and alter the characteristics of DOM from inflow to outflow. I tested these hypotheses by evaluating DOM temporal patterns and measuring annual export in seven-paired lake inflows and outflows. I then evaluated how ultraviolet (UV) exposure affected DOM …

Modeling Bark Beetle Outbreak And Fire Interactions In Western U.S. Forests And The Invasion Potential Of An Invasive Puerto Rican Frog In Hawaii Using Remote Sensing Data, Simon A. Bisrat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I used Moderate-Resolution Imaging Spectroradiometer (MODIS) imagery to answer two ecological questions. In the first project, I investigated the interactions between bark beetle-caused tree mortality and fire occurrence in western U.S. forests. I used remotely sensed fire data detected by MODIS satellite and bark beetle-caused tree mortality data. I tested the hypothesis that there is an increased probability of fire incidence in bark beetle-damaged forests compared to healthy forests using conditional probability modeling across the national forests of the western U.S. regardless of forest type. My results did not show a consistent pattern (increase or decrease of conditional probability of …

A Multi-Scale Evaluation Of Pygmy Rabbit Space Use In A Managed Landscape, Tammy L. Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Habitat selection has long been viewed as a multi-scale process. Observed species responses to resource gradients are influenced by variation at the scale of the individual, population, metapopulation, and geographic range. Understanding how species interact with habitat at multiple levels presents a complete picture of an organism and is necessary for conservation of endangered species. The main goal of this dissertation is to evaluate distribution, relative abundance, and habitat selection of a rare species, the pygmy rabbit Brachylagus idahoensis, at multiple scales in order to improve management and conservation for this species.

At the broadest scale, pygmy rabbit occurrence …

Greater Sage-Grouse Seasonal Ecology And Responses To Habitat Manipulations In Northern, Utah, Eric T. Thacker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Declining greater sage-grouse populations (Centrocercus urophasianus; hereafter sage-grouse) have led to increased concern regarding the long-term stability of the species. Previous research has identified factors contributing to the observed population declines. Habitat degradation and loss have been implicated as major factors in population declines. Although much is known about sage-grouse biology, more information is needed about population responses to specific management actions. This research was conducted to document sage-grouse responses to site-specific management actions. Additionally, I evaluated sage-grouse temporal and seasonal habitat-use and the comparability of techniques used by range and wildlife managers to measure vegetation responses of …

The Influence Of Collective Action And Policy In The Development Of Local Food Systems, Lori Porreca

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The modern global agrifood system has had significant negative impacts on consumers and producers. This has precipitated the rise of local food systems that are purported to improve the health and livelihoods of consumers and producers. High expectations have led to significant public and private resources dedicated to the development of local food systems. Despite this, there has been little systematic research exploring the social and institutional conditions that facilitate or frustrate local food system development.

Using a comparative case study approach, this study explored the ways local structural conditions, collective action, food system policies, and the political context affect …

The Hypericum Perforatum Herb As An Antimycobacterial Agent And Its Implications As An Additional Tuberculosis Medication, Trent W. Mortensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An immediate demand exists for new tuberculosis (TB) antibiotics due to the ever-increasing spread of drug-resistant strains. The drug-development process goes through four phases, the first (Phase 0) of which is to demonstrate and investigate drug effectiveness and toxicity. This research investigated the effectiveness of the Hypericum perforatum herb (commonly St. John's wort (SJW)) in its growth inhibition of mycobacteria and its viability effect on human lung cells.

Organic-solvent SJW extracts were effective at inhibiting every nonpathogenic genetically sequenced Mycobacterium isolate currently available (six isolates) in preliminary studies. Quantitative studies of five Mycobacterium isolates showed an order of concentration sensitivity …

Asymmetric Interspecific Competition Between Specialist Herbivores That Feed On Tamarisk In Western Colorado, Nina P. Louden

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Four closely related species of leaf beetles (Diorhabda spp.; Coleoptera: Chrysomelidae) have been introduced into the western United States as biocontrol agents for the invasive Eurasian shrub tamarisk (Tamarix spp.; Violales: Tamaricaceae). These beetles have since continued to spread and establish throughout the western United States. Another exotic insect, the tamarisk leafhopper (Opsius stactogalus, Fieber; Hemiptera: Cicadellidae), had previously become established in these areas and now shares tamarisk as a host plant with the beetles. To assess more carefully the potential for interactions between leafhoppers and beetles, field censuses and cage studies were conducted to determine …

Survival Of Mycoplasma Species In Recycled Bedding Sand And Possible Implications For Disease Transmission To Ruminants, Anne E. Justice-Allen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mycoplasmas are a group of bacteria which are small in size, lack a cell wall, and have small genomes in comparison to other bacteria. The members of the group that are pathogenic utilize several mechanisms to evade the host's immune system. These processes affect surveillance and control mechanisms such as serologic testing and vaccination. Many of these organisms cause diseases of livestock, which heavily impact production parameters such as weight gain, milk yield, and egg production. Mycoplasmas also cause disease in people.

Mycoplasma spp. can cause mastitis, metritis, pneumonia, and arthritis. The currently documented routes of transmission of Mycoplasma spp. …

Comparative Performance Of Fluorometry And High Performance Liquid Chromatography In The Detection Of Aflatoxin M1 In Two Commercial Cheeses, Gustavo Peña

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Aflatoxin M1 (AFM₁) is frequently found in milk and dairy products. It is a metabolite formed in cows from aflatoxin B1 (AFB₁), contained in animal feeds. In cheese production AFM₁ distributes between curds and whey. In this study, cows were fed 64 µg/AFB₁/d for the high treatment, and 5 µg/AFB₁/d for the low treatment, to obtain milk contaminated with AFM1 over the 0.5 µg/L and under 0.05 µg/L restrictions, respectively. Cheese was manufactured with milk contaminated with AFM₁ at 0.8 and 0.03 ìg/kg by the higher and lower …

Evapotranspiration Of Kentucky Bluegrass, Lynda L. Fenton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rapid population growth in arid regions of the western US is placing increased demand on water resources. Variability in precipitation and common occurrence of drought have promoted scrutiny of water use in urban lawns and gardens. However, few reliable measurements of water use of these landscapes exist. Quantifying the amount of water used vs. required by landscapes such as turfgrass would allow significant water conservation. Evapotranspiration (ET) is affected by biophysical factors such as: available energy, turbulent mixing, saturation deficit, soil water, and stomatal conductance. In order to simulate the water use by turfgrass, the relative importance of these processes …

Financial Feasibility Of High Performance Low Rise Steel Buildings, Yolanda Maria Baez Batista

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Comparative performance evaluation including life cycle cost is currently being conducted on a series of conventional and base-isolated case study buildings. Alternative design approaches and their influence in cost were to be evaluated. This investigation is intended to contribute in the development of isolated structures by allowing engineers to communicate the cost of higher performance systems to their clients. The reported effort is part of a larger cost-benefit study for isolated steel buildings, and the purpose of this thesis is to compare initial investment of 3-story conventional and isolated steel buildings and determine how isolation affects the cost of the …

Introduced Sport Fish And Fish Conservation In A Novel Food Web: Evidence Of Predatory Impact, Kevin Lee Landom

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study addressed a fundamental question in applied ecology and conservation; what is the predatory impact of introduced piscivorous sport fish on imperiled native fish populations? More specifically, which of many introduced species and size-classes represent the greatest threats and should be targeted for control? In order to explore this important question, an integrated analysis of stable isotopes, quantified observed diet analysis, and stable isotope mass-balance models were used to quantify trophic interactions. These tools were used to construct food web models that were then compared to draw inferences regarding the relative contribution of prey fish, including rare native fish, …

Characterizing Ecologically Relevant Variations In Streamflow Regimes, Kiran J. Chinnayakanahalli

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Maintaining the ecological health of streams is vital for sustainable water resources management. Streamflow is a primary factor influencing the structure and function of ecological communities. A quantitative understanding of how stream biota respond to variation in streamflow is required for stream bioassessment. This dissertation focuses on quantifying relationships between streamflow regime and stream macroinvertebrate richness and composition. The contribution comprises statistical models that predict stream macroinvertebrate class from streamflow regime and predict streamflow regime from watershed attributes, and a tool that helps derive watershed attribute variables used in these models.

The dissertation is a collection of three papers. In …

Optimizing The Physical And Nutritional Environment Of Unleached Root-Zones, Curtis B. Adams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Unleached root-zones represent an environmental ideal by eliminating wasteful leaching of nutrients and water. NASA grows plants in space in unleached root-zones, incorporating polymer-coated fertilizer (PCF) into a ceramic media (Turface or Profile). However, lack of growth productivity in space has led to the need for research to improve the nutritional and physical environment of the root-zone, which is the objective of this research. PCF types are diverse in release characteristics and the effects of temperature and substrate water content have not been well characterized. In spite of widespread use, studies on chemical properties and applied studies to verify soil …

Physiological And Molecular Function Of Hap3b In Flowering Time Regulation And Cold Stress Response, Mingxiang Liang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Heme-activated proteins (HAPs) are transcription factors that have multiple roles in plant growth and development, such as embryogenesis, flowering time control, and drought tolerance.

In the present study I found that HAP3b was also involved in controlling response to cold stress. Transcript profiling and gene expression analyses indicated that HAP3b repressed the CBF3 regulon under normal growth conditions. As a result, plants with HAP3b-overexpressed showed decreased survival rates while plants homozygous for the null allele hap3b showed an improved freezing tolerance compared to wild-type plants.

To understand the mechanism of HAP3b in Arabidopsis, i.e. whether it also acts …

Development Of A Laboratory Based System For Selecting Insect Pathogenic Fungi With Greatest Potential For Success In The Field, Chad Alton Keyser

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Many insects are important agricultural pests, and active control is necessary to keep them at abeyance. The naturally occurring entomopathogenic fungus Metarhizium is a promising tool to control pest insects, and its use avoids the well-known harmful side effects of chemical pesticides. Thousands of unique isolates of Metarhizium exist throughout the world. These isolates vary widely in their ability to cause infection and to tolerate stressful habitats. The research reported here tests the THESIS: A laboratory-based system can be devised that identifies, from among many Metarhizium isolates, those isolates with the greatest potential for successful biological control of pest insects …

The Effect Of Irrigation Diversions On The Mountain Whitefish (Prosopium Williamsoni) Population In The Big Lost River, Patrick Allen Kennedy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Management agencies documented a decline in the mountain whitefish (Prosopium williamsoni) population on the Big Lost River, and unscreened diversions were recognized as a potential factor for this decline. Research suggests the Big Lost River mountain whitefish population is genetically unique, and it has been petitioned for protection under the Endangered Species Act. In 2007, a basin-wide synopsis of diversions was conducted to describe relative entrainment and identify diversions that entrained the most mountain whitefish. This larger scaled synopsis facilitated a more precise assessment of entrainment by a subset of diversions in 2008. In 2008, the volume that …

Ecological Effects Of Genotypic Diversity On Community And Ecosystem Function, Megan K. Kanaga

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Genotypic diversity within populations can have important evolutionary consequences, but the ecological effects of intraspecific genetic variation on community and ecosystem function have only been studied in a few systems. I present the results of a three-year study designed to address the ecological impacts of genotypic diversity in quaking aspen (Populus tremuloides Michx.), using aspen genotypes planted across genotypic diversity levels (monoculture and mixture) and watering treatment levels (well-watered and water-limited). First, I demonstrated that significant variation exists among genotypes for a wide range of growth, morphological and physiological traits, and quantified high heritability and coefficient of genetic variation …

The Effects Of Social Status And Learning On Captive Coyote (Canis Latrans) Behavior, Lynne Barbara Gilbert-Norton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Many canids live within hierarchical social systems that could promote differences in learning or in behavior between ranked individuals. Differences in foraging and territorial behavior have been observed between ranked coyotes (Canis latrans), yet effects of learning and social status on coyote behavior are not thoroughly understood. I explored a) coyote response to an artificial scent boundary and whether response differed by status, b) how foraging coyotes tracked temporal resource change, and c) how coyotes find spatially distributed food, and the effect of dominance on foraging behavior. I used male/female pairs of captive coyotes at the National Wildlife Research Center …

Designing An Instrument Based On Native Fluorescence To Determine Soil Microbial Content At A Mars Analog Site, Heather D. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

For this research project we designed an instrument to detect bacteria via biomolecular fluorescence. We introduce the current understanding of astrobiology, our knowledge of life beyond Earth, and the commonality of Earth life as it pertains to the search for life on Mars. We proposed a novel technique for searching for direct evidence of life on the surface of Mars using fluorescence. We use the arid region of the Mojave Desert as an analog of Mars. Results indicate the fluorescence of the biotic component of desert soils is approximately as strong as the fluorescence of the mineral component. Fluorescence laboratory …

Alternative Sampling And Analysis Methods For Digital Soil Mapping In Southwestern Utah, Colby W. Brungard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Digital soil mapping (DSM) relies on quantitative relationships between easily measured environmental covariates and field and laboratory data. We applied innovative sampling and inference techniques to predict the distribution of soil properties, soil attributes, taxonomic classes, and dominant vegetation across a 30,000-ha complex Great Basin landscape in southwestern Utah. This arid rangeland was characterized by rugged topography, diverse vegetation, and intricate geology. Environmental covariates calculated from digital elevation models (DEM) and spectral satellite data were used to represent factors controlling soil development and distribution. We investigated optimal sample size and sampled the environmental covariates using conditioned Latin Hypercube Sampling (cLHS). …

Summer Home Range Fidelity In Adult Female Elk (Cervus Elaphus) In Northwestern Colorado, April M. Brough

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding the degree of spatial fidelity of individuals within a species increases our ability to manage appropriately. Elk (Cervus elaphus) is a highly managed species in the Intermountain West, but there is little research evaluating summer home range fidelity of individual elk. We evaluated fidelity of 72 adult female elk to individual summer-fall home ranges in the White River study area in northwestern Colorado during two consecutive summers. Based on individual kernel-estimated utilization distributions, we used (1) the Volume of Intersection (VI) statistic and (2) interannual distances between centers of mass to compare summer range overlap and distribution. …

Effects Of Coyote Removal On Pronghorn And Mule Deer Populations In Wyoming, Dylan Earl Brown

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I studied the relationship between coyote (Canis latrans) removal and pronghorn (Antilocapra americana) and mule deer (Odocoileus hemionus) density and fawn:doe ratios in southwest Wyoming and northeast Utah in 2007 and 2008. Coyote removal variables studied included the number of coyotes removed, ground hours worked, total hours worked, coyotes removed/aerial gunning hour, coyotes removed/ground work hour, and coyotes removed/total effort hour. None of the variables explained changes observed in fawn:doe ratios of pronghorn or mule deer. The number of coyotes removed, ground hours worked, total hours worked, and coyotes removed/aerial gunning hour were positively …

Effects Of Starch Addition On Low Fat Rennet Curd Properties And Their Partitioning Between Curd And Whey, Kelly Marie Larsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study determined the impact of starches on the properties of low fat rennet curd as measured by microstructural and instrumental analysis. In experiment 1, 17 starches were initially screened for swelling power, impact of curd yield at 5 g/L and 10 g/L in milk, and settling in rennet-induced partially acidified low fat curd.

Starches examined were narrowed down to five in experiment 2; they included: modified waxy corn starch, waxy rice starch, instant tapioca starch, dextrin, and a modified tapioca starch. These starches were added to skim milk to make rennet-induced partially acidified milk gels. Gels were made by …