Digital Commons Network^™

Transmitter Localization Using Autonomous Robotic Swarms, Joshua S. Adams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this research is to design a proof of concept system that is capable of locating a hidden radio transmitter and to investigate methods of multi-agent formation control with a specific interest in the effectiveness of these methods on the overall objective of locating this transmitter. A system is proposed and developed in which autonomous agents work together to locate this transmitter and their responsiveness is analyzed while using formations based both on a behavioral system and a system derived from centroidal Voronoi tessellations. Many software adaptations to the existing MASnet program are required, as well as some …

Applying Information Visualization To Computer Security Applications, Robert Bruce Whitaker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presents two phases of research in applying visualization to network security challenges. The first phase included discovering the most useful and powerful features in existing computer security visualizations and incorporating them into the AdviseAid visualization platform, an existing software package. The incorporation of such a complete feature set required novel resolution of software engineering, human factors, and computer graphics issues. We also designed additional novel features, such as plugin interfaces, allowing for rapid prototyping and experimentation with novel visualization features and capabilities. The second phase of the research focused on the development of novel visualization techniques themselves. These …

Stormwater Monitoring And Resident Behavior In A Semi-Arid Region, Jennifer Abraham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The combined effect of land-use alterations and introduced diffuse anthropogenic pollutants to the earth's surface in suburban/urban zones often sparks a decrease in stormwater quality in the area, and contributes to nonpoint source pollution in receiving waters. The ponds at the Utah Botanical Center (UBC) located in Kaysville, UT, regularly experience algal blooms, which in turn cause low dissolved oxygen levels in the waters, indicating high concentrations of inflowing pollutants. The goal of this thesis paper was to describe the findings from the water quality monitoring implemented at both the inlet and outlet of the UBC ponds in order to …

Development Of An Innovative Statewide Population Monitoring Program For Mule Deer, Heather H. Bernales

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Monitoring population trend and estimating vital demographic parameters are essential for effective management of a mule deer (Odocoileus hemionus) population. Because of financial constraints, many wildlife agencies use computer models to obtain indirect indices of population size and trend as an alternative to annual field-based estimates of population size. These models are based primarily on herd composition counts and harvest rates from hunter-harvest surveys, and are rarely field validated. I developed an alternative method for monitoring population dynamics of wintering populations of mule deer. I designed a hybrid monitoring program that combined annual vital rate monitoring to track changes in …

Changes In Hybrid Poplar Endophytic Microbial Diversity In Response To Trichloroethylene Exposure, Jared S. Ervin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Remediation of trichloroethylene (TCE) is a major priority for many contaminated sites all over the industrialized world including Hill Air Force Base, UT (HAFB). Phytoremediation as part of a cleanup strategy is an appealing option, and trees at HAFB have been studied to this end. Trees have also been used to delineate groundwater plumes because the passive uptake of organic contaminants by trees generally results in a direct relationship between tree and groundwater TCE concentrations if the trees are using the contaminated groundwater. However, the concentrations of plant-produced TCE metabolites can vary greatly. It was hypothesized that the endophytic microbial …

Transesterification And Recovery Of Intracellular Lipids Using A Single Step Reactive Extraction, Daniel R. Nelson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A single-step, extractive reaction for extraction of lipids such as biodiesel components, omega-3 fatty acids, or other triglycerides from microbial cells was examined. Conventional methods for lipid extraction use toxic solvents, and require multiple steps and long processing times. When the goal is to produce fatty acid methyl esters or FAMEs, the extracted lipids are subjected to a separate transesterification reaction with simple alcohols in the presence of an acid or base catalyst. A simplified, single-step reactive extraction method can be applied that combines the sequential extraction followed by transesterification using acidified alcohols - a process known as in situ …

Critique Of A Wildlife Habitat Evaluation Method Applied To Residential Open Space, Sarah Rigard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To this date, little research has been done evaluating the quality of wildlife habitat provided by open space in residential areas. Quality wildlife habitat for the purposes of this study is defined as those areas which contain the physical and biological characteristics necessary to support native wildlife species of the region. This thesis critiqued a wildlife habitat assessment method used in a nationwide study of residential open space for the purpose of better understanding the research conducted by the study and to inform similar, future habitat evaluations of landscapes altered by human activity to accommodate residential land use. The methodology …

Comparative Ecology Of Narrowly Sympatric Horned Lizards Under Variable Climatic Conditions, Kevin V. Young

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We studied the Flat-tailed Horned Lizard, Phrynosoma mcallii, and the Sonoran Horned Lizard, P. goodei, in an area of narrow sympatry near Yuma, Arizona, and found they overlapped broadly in use of available food resources, body size, and growth rates. We compared diet (Chapter 2), growth and reproduction (Chapter 3), and survivorship (Chapter 4) of P. mcallii and P. goodei during two years of drought followed by a year of higher-than-average rainfall. We predicted that P. mcallii would be more tolerant of drought conditions than its congener, since P. mcalliiis found only in an extremely arid region while …

Object-Based Segmentation And Classification Of One Meter Imagery For Use In Forest Management Plans, W. Kevin Wells

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research developed an ArcGIS Python model that extracts polygons from aerial imagery and assigns each polygon a vegetation type based on a modified set of landcover classes from the Southwest Regional Gap Analysis Project. The model showed an ability to generate polygons that accurately represent vegetation community boundaries across a large landscape. The model is for use by the Utah Division of Forestry, Fire, and State Lands to assist in the preparation of forest management plans. The model was judged useful because it was easy to use, it met a designated 50% threshold of useable polygons, and it met …

Decentralized Coordination Of Multiple Autonomous Vehicles, Yongcan Cao

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation focuses on the study of decentralized coordination algorithms of multiple autonomous vehicles. Here, the term decentralized coordination is used to refer to the behavior that a group of vehicles reaches the desired group behavior via local interaction. Research is conducted towards designing and analyzing distributed coordination algorithms to achieve desired group behavior in the presence of none, one, and multiple group reference states.

Decentralized coordination in the absence of any group reference state is a very active research topic in the systems and controls society. We first focus on studying decentralized coordination problems for both single-integrator kinematics and …

Maternal Effects In Transmission Of Self-Medicative Behavior From Mother To Offspring In Sheep, Udita Sanga

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mammals begin learning food preferences in utero and maternally mediated influences early in life help offspring develop their feeding habits. Mammals also learn by individual experience to ingest medicinal compounds such as polyethylene glycol (PEG), which attenuates the negative post-ingestive effects of tannins, a group of potentially toxic plant secondary compounds. The objective of this study was to investigate the transmission of acquired self-medicative behavior from mother to offspring using polyethylene glycol (PEG) as a medicine to relieve malaise caused by tannins. I hypothesized that: 1) mothers trained to associate the beneficial effects of PEG while consuming tannins will pass …

A Comparative Study To Identify Factors Affecting Adoption Of Soil And Water Conservation Practices Among Smallhold Farmers In The Njoro River Watershed Of Kenya, Steven P. Huckett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Natural resource conservation is important for human well-being, especially in fragile environments of developing countries. This study occurred in 2006 among 6,500 smallhold farmers residing along a 25-km segment of a heavily utilized river. Research objectives were to determine use and adoption constraints for 14 soil and water conservation practices (SWCPs). Farms were reportedly contributing to a decline in river water quality via soil erosion. Recent occupation of the upper watershed by immigrants magnified concerns that resource degradation could escalate. A multi-method approach incorporating quantitative surveys, qualitative interviews, and participant observation was used to interpret constraining factors within the biophysical …

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 …

Parents As Partners In Kindergarten And Second Grade Literacy Instruction: A Qualitative Inquiry Into Student-Authored Traveling Books, Dorothy C. Little

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this research was to study a sociocognitive “student/parent/peer authoring community” called Traveling Books (TBks) in kindergarten and second grade in a public elementary school setting. TBks are teacher-made vehicles for involving parents in peer-based literacy environments. The study was based on Epstein's theory that increasing overlap of students' spheres of influence, home, school, and community, creates a greater likelihood that children will learn what the parents want them to learn. The aim was to locate essential elements that triggered learning processes to occur and to discover research-based fundamentals still missing from TBks.

This qualitative inquiry incorporated the …

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 …

Nutrient Utilization From Anaerobic Digester Effluent Through Algae Cultivation, Shantanu Wahal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nutrients present in digested animal waste can be utilized for algae cultivation under suitable conditions. Algal growth, however, depends on the chemical forms and speciation of these nutrients. In this study a chemical equilibrium model was first used to describe nutrient speciation and predict conditions that enhance the solubility of nutrients in anaerobic digester effluent. Dilution with water and separation of large particulates greatly improved nutrient availability and light penetration - conditions favorable for algal cultivation. Algae growth was tested using three strains - Scenedesmus dimorphous (UTEX # 417), Chlorella vulgaris (UTEX# 265), and an algal isolate (designated as LLAI …

Terrestrial Ecosystem Classification In The Rocky Mountains, Northern Utah, Antonin Kusbach

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Currently, there is no comprehensive terrestrial ecosystem classification for the central Rocky Mountains of the United States. A comprehensive classification of terrestrial ecosystems in a mountainous study area in northern Utah was developed incorporating direct gradient analysis, spatial hierarchy theory, the zonal concept, and concepts of diagnostic species and fidelity, together with the biogeoclimatic ecosystem classification approach used in British Columbia, Canada.

This classification was derived from vegetation and environmental sampling of both forest and non-forest ecosystems. The SNOwpack TELemetry (SNOTEL) and The National Weather Service (NWS) Cooperative Observer Program (COOP) weather station network were used to approximate climate of …

Targeting Fatty Acid-Activated Pathways In The Somatosensory System, Tian Yu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Given the dramatic rise in obesity and the diseases linked with it, it is becoming increasingly important to understand the mechanisms that underlie the body's ability to recognize fat. The chemoreception of dietary fat in the oral cavity has largely been attributed to activation of the somatosensory system that relays the textural properties of fat. However, the ability of fatty acids, which are believed to represent the proximate stimulus for fat taste, to activate trigeminal ganglionic neurons has remained unexplored. In general, my research has provided the first evidence of fatty acids activating the somatosensory system by increasing the intracellular …

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 …

Ecology Of Isolated Greater Sage-Grouse Populations Inhabiting The Wildcat Knolls And Horn Mountain, Southcentral Utah, Christopher J. Perkins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Greater sage-grouse (Centrocercus urophasianus) currently inhabit about 56% of pre-settlement distribution of potential habitat. In 2005, the Castle Country Adaptive Resources Management Local Working Group (CaCoARM) was formed to address concerns regarding local sage-grouse populations in Carbon and Emery counties. In 2006-2007, CaCoARM identified the Wildcat Knolls and Horn Mountain as areas of special concern for greater sage-grouse conservation. Both sites selected by the group were inhabited by what appeared to be small isolated sage-grouse populations. Factors limiting small isolated greater sage-grouse populations throughout its range are diverse and largely site-specific.

During 2008-2009, I captured, radio-collared, and monitored …

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 Pursuit Of An Unequivocal Primary Representation, Delroy A. Brinkerhoff

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A chief human characteristic is the desire and ability to change the world. Prior planning is crucial when those changes are complex and extensive, and require the cooperation of many people. To satisfy this need, many disciplines have developed specialized notations for representing the plans. Developers in one discipline, computer-based instruction, are burdened by the current need to use two separate notations. Instructional experts design the instruction and represent the design with a primary representation. The instruction described in a primary representation is easy to see, which makes the representation suitable for evaluation, communication, and enhancement. Programmers translate the primary …

Role Of Protein Kinase C Isotypes In 1,25-Dihydroxyvitamin D3 Mediated Signal Transduction Through The 1,25d3 Membrane Associated, Rapid Response Steroid Binding Receptors In Chick Intestinal Cells, Sakara Tunsophon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

It is now accepted that 1,25(OH)2D3 mediates its rapid actions on the control of phosphate and calcium homeostasis through its membrane receptor termed the 1,25D3-MARRS (membrane associated rapid response steroid binding) protein. I determined the various PKC isotypes involved in the rapid regulation of phosphate uptake and calcium extrusion in chick intestinal cells. 1,25(OH)2D3-mediated phosphate uptake was stimulated within 1 min after addition of the hormone. Western blot analyses on isolated intestinal cells treated with steroid hormone resulted in dose-dependent increases in PKC alpha and PKC beta in postnuclear centrifugation fractions, but not in the low speed centrifugation fractions. The …

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 …

Examination Of Behavioral Momentum With Staff As Contextual Variables In Applied Settings With Children With Autism, Mark P. Groskreutz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Behavioral momentum theory proposes that the persistence of behavior when exposed to disruptors provides an appropriate measure of the strength of behavior. Basic research has consistently demonstrated that behaviors that occurred in a context with higher overall rates of reinforcement (rich contexts) were more persistent than other behaviors that have occurred in a context with relatively lower rates of reinforcement (lean contexts). More surprisingly, behavioral momentum theory goes on to assert that this greater persistence in richer contexts is found even when rate of responding is lower in the rich context, and when the greater richness is due to noncontingent …

Language Brokering In Latino Families: Direct Observations Of Brokering Patterns, Parent-Child Interactions, And Relationship Quality, Kee J. E. Straits

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

With the growing percentage of immigrant families in the USA, language transition is a common immigrant experience and can occur rapidly from generation to generation within a family. Child language brokering appears to occur within minority language families as one way of negotiating language and cultural differences; however, the phenomenon of children translating or mediating language interactions for parents has previously been hypothesized to contribute to negative outcomes for children, such as role-reversals and parentification, emotional distancing and lack of communication, increased parent-child conflict, and increased internalizing/externalizing disorders. The current study used direct observations of 60 Spanish-speaking parent-child dyads (30 …

The Influence Of Landscape And Weather On Foraging By Olfactory Meso-Predators In Utah, Rebekah E. Dritz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Predation by olfactory meso-predators has a large impact on avian nest success, particularly for ground-nesting waterfowl. Olfactory predators rely on odors to locate their prey. Weather conditions (e.g. wind speed, humidity, and temperature), vegetation, and landscape features affect the dissipation rate of odors and could affect the foraging efficiency of olfactory predators. I conducted 2 studies to determine if weather and landscape impact predator foraging ability and behavior: a predator survey study and an artificial nest study. The objective of the predator survey was to investigate how landscape and weather conditions interact to influence the distribution of olfactory meso-predators [e.g. …