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Detecting Organic Molecules On The Surface Of Inorganic Dust Particles Using Aerosol Mass Spectrometry, Sileola B. Akinsiku

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Detection of organic molecules present on the surface of dust particles is important in homeland security, agriculture, and several other applications. The research presented reports the ability of the aerosol mass spectrometer (AMS) to detect molecules on the surface of dust particles without detecting the particle core.

Experiments were carried out to detect semi-volatile organic compounds adsorbed onto the surface of particulates without interference from the dust particle core. Methyl salicylate, oleic acid, and organophosphorus pesticides such as Malathion were detected on the surface of particles representative of dust-type materials. Zeolite powders were used as aerosol support, representative of a …

Speciation, Species Concepts, And Biogeography Illustrated By A Buckwheat Complex (Eriogonum Corymbosum), Mark W. Ellis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The focus of this research project is the complex of infraspecific taxa that make up the crisp-leaf buckwheat species Eriogonum corymbosum (Polygonaceae), which is distributed widely across southwestern North America. This complex provides an ideal taxonomic group for research into population relationships and speciation. To avoid unnecessary debates about taxonomic validity or contentious issues regarding appropriate species definitions, the historical evolution of the species concept is first reviewed in detail, demythologizing an often-assumed species problem. Following that review, the E. corymbosum complex is examined specifically.

Although eight varieties of E. corymbosum are currently recognized based on morphological characters, this group …

Disordered: A Tale Of The Body, Elizabeth M. Benson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

While a body of creative nonfiction writing exists regarding experiences with various psychological disorders, few personal accounts have been written about the physical complications of Generalized Anxiety Disorder. Some memoirs tell a tale of serious illness in a straightforward narrative line. On the opposite end of this spectrum, other memoirs intentionally blur the lines of truth and heighten the confusion of a disorder. This thesis is as much a narrative of my experience with Generalized Anxiety Disorder as it is a response to the void in creative nonfiction surrounding this specific disorder and the narrative forms others have chosen to …

Optimal Candidate Generation In Spatial Co-Location Mining, Zhongshan Lin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Existing spatial co-location algorithms based on levels suffer from generating extra, nonclique candidate instances. Thus, they require cliqueness checking at every level. In this thesis, a novel, spatial co-location mining algorithm that automatically generates co-located spatial features without generating any nonclique candidates at any level is proposed. Subsequently, this algorithm generates fewer candidates than other existing level-wise, co-location algorithms without losing any pertinent information. The benefits of this algorithm have been clearly observed at early stages in the mining process.

Modeling The Evolution Of Insect Phenology With Particular Reference To Mountain Pine Beetle, Brian P. Yurk

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Climate change is likely to disrupt the timing of developmental events (phenology) in insect populations in which development time is largely determined by temperature. Shifting phenology puts insects at risk of being exposed to seasonal weather extremes during sensitive life stages and losing synchrony with biotic resources. Additionally, warming may result in loss of developmental synchronization within a population, making it difficult to find mates or mount mass attacks against well-defended resources at low population densities. It is unknown whether genetic evolution of development time can occur rapidly enough to moderate these effects.

The work presented here is largely motivated …

Exploring The Spawning Dynamics And Identifying Limitations To The Early Life-History Survival Of An Important, Endemic Fish Species, Sara Elizabeth Seidel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

For many native, imperiled salmonid species, the prioritization of recovery and conservation efforts hinges upon the identification of a species most limiting life stage. The early life-history stage can be a limiting life stage for fish, and given the importance of the reproductive stage to overall persistence, there is a need to better understand the spawning ecology and early life history of many salmonids. The Logan River, in northern Utah, contains one of the largest metapopulations of imperiled Bonneville cutthroat trout (BCT) throughout the Bonneville Basin. Little research has evaluated the temporal and spatial distribution of BCT spawning nor quantified …

Linking Space Use And Behavior In Clark's Nutcracker: An Explanation For Seasonal Variation In Space Use, Teresa J. Lorenz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Clark's Nutcrackers (Nucifraga columbiana) are important seed dispersers for at least 10 species of conifer in western North America and are obligate mutualists for the subalpine tree, whitebark pine (Pinus albicaulis). Despite the important role they play in forest regeneration, space use by nutcrackers has not been formally studied. Several hypotheses exist to explain their year-round space use patterns. I tested one hypothesis that Clark's Nutcrackers migrate altitudinally between summer and autumn in one population in the Cascade Range, Washington. In 2006 and 2007, I compared seasonal differences in summer and autumn space use by 26 …

Simulation, Kriging, And Visualization Of Circular-Spatial Data, William James Morphet

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The circular dataimage is defined by displaying direction as the color at the same direction in a color wheel composed of a sequence of two-color gradients with color continuity between gradients. The resulting image of circular-spatial data is continuous with high resolution. Examples include ocean wind direction, Earth's main magnetic field, and rocket nozzle internal combustion flow. The cosineogram is defined as the mean cosine of the angle between random components of direction as a function of distance between observation locations. It expresses the spatial correlation of circular-spatial data. A circular kriging solution is developed based on a model fitted …

Mycorrhizae In Sagebrush-Steppe Community Restoration: Mycorrhizal Dependency Of Invasive And Native Grasses With Intraspecific And Interspecific Competition, Dara S. Scherpenisse

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mycorrhizae have been used in restoration for decades. However, studies assessing the use of mycorrhizae in Bromus tectorum-invaded areas of the Great Basin are limited. Two greenhouse pot experiments were conducted to assess the role of mycorrhizae in sagebrush restoration.

The first objective (Chapter 2) was to determine the response of Pseudoroegneria spicatum, Elymus elymoides, and B. tectorum to mycorrhizal symbiosis by altering phosphorus, density, species, presence of mycorrhizae and water levels in a 5 factor design. To assess the mycorrhizal response, a variety of morphological and physiological traits were measured, such as tissue P concentration, specific …

"Big, Smelly, Salty Lake That I Call Home": Sense Of Place With A Mixed Amenity Setting, Carla Koons Trentelman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Drawing from literature on place, this dissertation studies place dynamics in relationships between people and a mixed amenity place. Using Great Salt Lake (GSL), Utah, as a case study, I use a social constructionist approach to examine the sense of place held by those who live nearest to the lake. I analyze qualitative interview and focus group data as well as quantitative survey data to discern the meanings the lake holds for these nearest neighbors and to examine distinctions between people who see the lake differently.

This study is relatively unique in its examination of relationships with a mixed amenity …

The Regulation Of Epithelial Sodium Channels In Mammalian Taste Receptor Cells, Arian F. Baquero Gonzalez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nutrient recognition is one of the main physiological roles of the gustatory system. In mammals, it is well established that the taste of sodium salts is primarily mediated by sodium influx through the epithelial sodium channel. The epithelial sodium channel is a sodium-specific ion channel that is expressed across a wide range of transporting epithelia such as colon, kidney, and taste. In addition to its role as a salt taste receptor, sodium influx through the epithelial sodium channel is important systemically for maintaining sodium balance and blood pressure. Following our earlier work on the endocrine regulation of salt taste at …

Patterns Of Learning Object Reuse In The Connexions Repository, S. M. Duncan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Since the term learning object was first published, there has been either an explicit or implicit expectation of reuse. There has also been a lot of speculation about why learning objects are, or are not, reused. This study quantitatively examined the actual amount and type of learning object use, to include reuse, modification, and translation, within a single open educational resource repository–Connexions. The results indicate that about a quarter of used objects are subsequently reused, modified, or translated. While these results are repository specific, they represent an important first step in providing an empirical evaluation of the frequency and some …

Empirically Examining Prostitution Through A Feminist Perspective, Shyann Child

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this thesis is to empirically explore prostitution through a feminist perspective. Several background factors are explored on a small sample of women in the northeastern United States. Some of these women have been involved in an act of prostitution in their lifetime; some have not. This research will add to the body of knowledge on prostitution, as well as highlight the unique experiences of women. The goal is to understand whether or not these life experiences have had a hand in women's choices to engage in prostitution.

Targeting Fat-Sensitive Pathways In Enteroendocrine Cells Using Nanoparticle-Mediated Drug Delivery, Bhavik P. Shah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The current epidemic of obesity has been linked to an increase in fat intake associated with the Western diet. Nutrient-induced stimulation of enteroendocrine cells in the small intestine leads to the release of hormones that contribute to satiety and the control of food intake. In particular, ingested fat, specifically in the form of free fatty acids, is potent activator of enteroendocrine cells in the proximal small intestine. However, the underlying signaling cascade that free fatty acids initiate in these enteroendocrine cells, which leads to secretion of satiety hormones, is not known. In general, my research is focused on identifying nutrient-responsive …

Evaluating The Relationship Between Women's Sexual Desire And Satisfaction From A Biopsychosocial Perspective, Katherine J. Chartier

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to evaluate the relationship between women's sexual desire and their reported level of sexual satisfaction. This study evaluated biological, psychological, and social factors of desire that might influence satisfaction. The sample for this study consisted of 77 Caucasian individuals, 45 women and 32 men, in their first marriage, who had been married on average 2 years. Results indicated that sexual desire was positively and significantly correlated with sexual satisfaction and that psychological and social factors most strongly explain women's sexual satisfaction. Further, women's perceptions of their own sexual desire, psychological and social, were more …

Naive Prey Versus Nonnative Predators: A Role For Behavior In Endangered Species Conservation, Stephanie A. Kraft

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fish are one of the most imperiled groups of vertebrates worldwide. Threats to fish fall into one of four general categories: physical habitat loss or degradation, chemical pollution, overfishing, and nonnative species introductions. Nonnative predatory fish often have a devastating impact on native prey, especially with endemic fish, whose restricted distribution and often limited evolutionary history with predators make them particularly susceptible to nonnative predators. One reason nonnative fish are often so efficient predators is that the native fish do not recognize the predator as a threat. Although many studies have examined the role of predator odor recognition, no fish …

Perceived Effectiveness Of Booster Sessions Following A Stepfamily Education Course, John Mitchell Vaterlaus

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The study's purpose was to determine if participants reported that booster sessions following a stepfamily education course were effective. Agencies in northern Utah that provide services to low-income (including minorities) families were used to recruit a sample of 487 males and 560 females. Participants were required to be in a relationship that formed a remarriage or to have children from a previous relationship, forming a stepfamily. Booster sessions were educational meetings that occurred four to six weeks after the completion of the stepfamily education course. Intervention theory states that as protective factors are implemented through prevention education they lessen the …

Inducing A Normal Phenotype In Breast Epithelial Cells Using A Three-Dimensional Basement Membrane Extract Culture System: A Study On The Reversion Of Cancer, Ross H. Booth

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Experimentally, traditional developmental models and transgenic animals consistently underscore the importance of studying cell behavior in the correct tissue context. However, live animal experimentation is inherently complex, and systematic assessment of the effects of individual variables, such as cell shape and matrix compliance on cell behavior, is extremely difficult at best. Two-dimensional monolayer culture of key individual cell types has provided abundant, fundamental information on cell response, but cannot be used to show the normal phenotype of breast epithelial cells. Furthermore, their results often fail to translate into in vivo and clinical studies. It has been previously established that normal …

Nitrogen Transport, Transformation And Cycling Through A Mountain Lake, Bull Trout Lake, Idaho, Usa, Ryan Settle Lockwood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of a mountain lake on nitrogen dynamics in a sub-alpine watershed were examined via watershed monitoring, mesocosm experiments, microcosm experiments, and enzymatic assays during spring and summer of a single year. Our study addressed the questions: (1) How does hydrologic transport through the lake affect the net fluxes of dissolved nitrogen (N) species? (2) What are the net effects of the littoral zone biota on dissolved N fluxes? (3) What are the seston and benthic uptake rates of nitrate? (4) What is the magnitude of N retention in littoral zone sediments? (5) What role does microbial hydrolysis of …

Maladaptive Schemas As A Predictor Of Residential Treatment Outcomes In Females With Eating Disorders, Jodi Leigh Cullum

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The present study aimed to examine the relationship between maladaptive schemas and treatment outcomes of adolescent and adult women with an eating disorder receiving residential treatment. Existing data were obtained from 67 females aged 11 to 47 years (m =18.61) that had entered residential treatment for anorexia nervosa (AN), bulimia nervosa (BN), or eating disorder not otherwise specified (EDNOS) at a Western United States residential eating disorder treatment facility. Pre- and posttreatment data were collected by the personnel at the facility on eating disorder symptomatology, mood, and core beliefs. Three hypotheses were tested: (a) that maladaptive schemas would be …

Greater Sage-Grouse And Energy Development In Northeastern Utah: Implications For Management, Leah Suzanne Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Concern regarding the effect of energy development on greater sage-grouse (Centrocercus urophasianus) is increasing as the search for fossil fuel intensifies. Sage-grouse may be especially sensitive to energy development because they require large, diverse areas of sagebrush (Artemisia spp.) habitat to complete their life cycle. Additionally, the network of pipelines, roads, and wells required by energy development may fragment sagebrush habitat isolating populations and contributing to genetic drift, inbreeding, local extinction, or rapid divergence.

Seep Ridge, located in northeastern Utah, is one area where sage-grouse habitat and energy development plans overlap. Approved leases call for the construction …

Maintaining Population Persistence In The Face Of An Extremely Altered Hydrograph: Implications For Three Sensitive Fishes In A Tributary Of The Green River, Utah, Jared L. Bottcher

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The ability of an organism to disperse to suitable habitats, especially in modified and fragmented systems, determines individual fitness and overall population viability. The bluehead sucker (Catostomus discobolus), flannelmouth sucker (Catostomus latipinnis), and roundtail chub (Gila robusta) are three species native to the upper Colorado River Basin that now occupy only 50% of their historic range. Despite these distributional declines, populations of all three species are present in the San Rafael River, a highly regulated tributary of the Green River, Utah, providing an opportunity for research. Our goal was to determine the timing and …

Soil Organic Carbon And Site Characteristics In Aspen And Evaluation Of The Potential Effects Of Conifer Encroachment On Soil Properties In Northern Utah, Mical K. Woldeselassie

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the Intermountain West, aspen (Populus tremuloides) has declined mainly due to a combination of successional processes, fire suppression and long-term use of ungulates which has led to replacement by conifers, sagebrush or other shrub communities. Conifer encroachment is believed to cause critical changes in the ecosystem properties. In order to understand the impacts of conifer encroachment on soil properties such as soil organic carbon (SOC) storage, soil morphology, and soil chemical properties, and the implications of such changes, it is very important to assess the soil properties under the two vegetation types. The objectives of this study …

On The Applicability Of Genetic Algorithms To Fast Solar Spectropolarimetric Inversions For Vector Magnetography, Brian J. Harker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The measurement of vector magnetic fields on the sun is one of the most important diagnostic tools for characterizing solar activity. The ubiquitous solar wind is guided into interplanetary space by open magnetic field lines in the upper solar atmosphere. Highly-energetic solar flares and Coronal Mass Ejections (CMEs) are triggered in lower layers of the solar atmosphere by the driving forces at the visible ``surface'' of the sun, the photosphere. The driving forces there tangle and interweave the vector magnetic fields, ultimately leading to an unstable field topology with large excess magnetic energy, and this excess energy is suddenly and …

An Empirical Investigation Of The Adaptive Nature Of Shame, Elizabeth Jacqueline Dansie

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Throughout the empirical psychological literature on emotion, the general consensus is that shame is maladaptive, while guilt is the adaptive moral emotion. Conversely, evolutionary psychology concludes that all emotions serve adaptive functions. Specifically, shame serves an appeasement function in social relationships. In order to investigate the true nature of shame, the current study used an experimental design. Specifically, a 2 (high shame, no shame) X 2 (high guilt, no guilt) design with a no-mistakes control group was implemented, and shame and guilt were operationalized through an evolutionary lens (i.e., shame as a nonverbal display, guilt as verbalizations of apology). Participants …

Goatsrue (Galega Officinalis) Seed Biology, Control, And Toxicity, Michelle Oldham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Goatsrue is an introduced perennial plant that has proven to have great invasive potential, leading to its classification as a noxious weed in many states and at the federal level. This research focused on seed biology, herbicide control, and toxic dynamics of goatsrue. Physical dormancy of mature goatsrue seed was tested through scarification using sulfuric acid with exposures of up to 60 minutes resulting in 100% germination. Comparison of dormancy for 26-year-old and 6-month-old goatsrue seed indicated aged seeds had reduced dormancy levels compared to newly harvested seeds, but had similar viability. Goatsrue seedling emergence was inversely related to burial …

A Comparative Study Of The Structural Features And Kinetic Properties Of The Mofe And Vfe Proteins From Azotobacter Vinelandii, Miguel Alejandro Pabon Sanclemente

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Biological nitrogen fixation is accomplished in the bacterium Azotobacter vinelandii by means of three metalloenzymes: The molybdenum, vanadium, and iron-only nitrogenase. The knowledge regarding biological nitrogen fixation has come from studies on the Mo-dependent reaction. However, the V- and Fe-only-dependent reduction of nitrogen remains largely unknown.

By using homology modeling techniques, the protein folds that contain the metal cluster active sites for the V- and Fe-only nitrogenases were constructed. The models uncovered similarities and differences existing among the nitrogenases regarding the identity of the amino acid residues lining pivotal structural features for the correct functioning of the proteins. These differences, …

Modeling Potential Native Plant Species Distributions In Rich County, Utah, Kathryn A. Peterson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Georeferenced field data were used to develop logistic regression models of the geographic distribution of 38 frequently common plant species throughout Rich County, Utah, to assist in the future correlation of Natural Resources Conservation Service Ecological Site Descriptions to soil map units. Field data were collected primarily during the summer of 2007, and augmented with previously existing data collected in 2001 and 2006. Several abiotic parameters and Landsat Thematic Mapper imagery were used to stratify the study area into sampling units prior to the 2007 field season.

Models were initially evaluated using an independent dataset extracted from data collected by …

The Effect Of An Ambient Olfactory Intervention On Time-On-Task And Performance During Participant Interaction With An Electronic Flashcard System, Aaron J. Loewer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to measure the influence of an ambient peppermint aroma on participants' time-on-task and performance while using FACTOR, an open-source e-Learning application. I proposed time-on-task was moderating between olfactory stimulation and performance.

A 2x2 research design measured interaction of group (nonscented, scented) and gender of participants (N = 65). The learning content consisted of 28 African countries. Two methods for measuring time-on-task were employed: participant self-report at six learning intervals, and second, video recordings captured by, and stored on each participant's computer.

Independent samples t tests were used to measure group and gender differences …

An Investigation Of Postzygotic Reproductive Isolation And Phenotypic Divergence In The Bark Beetle Dendroctonus Ponderosae, Ryan R. Bracewell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding reproductive isolation and divergence is the focus of speciation research. Recent evidence suggested that some Dendroctonus ponderosae populations produced hybrids with reproductive incompatibilities, a reproductive boundary undetected by phylogeographic analyses using molecular markers. Additionally, the unique bifurcated distribution of D. ponderosae and the proposed isolation-by-distance gene flow pattern around the Great Basin Desert provided a unique opportunity to investigate the evolution of postmating (postyzygotic) isolation while also understanding phenotypic divergence along latitudinal (climatic) gradients. First, I characterized the strength, biological pattern, and geographic pattern of postzygotic isolation in D. ponderosae by crossing increasingly divergent populations in a common garden …