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Watershed Management To Control Pollution In The Ayuquila River, Jalisco, Mexico, Luis Manuel Martinez Rivera

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Ayuquila River watershed is important to western Mexico because of its biodiversity, physiography, fisheries resources, and water production. However, human activities are continuingly affecting natural resources within the basin. Soil erosion, as result of land use change, agriculture in steep land, extensive grazing activities and forest fires; and water diversion and pollution of the Ayuquila River are two relevant issues that have affected the natural resources of this watershed.

This river system plays an important role in wildlife conservation, containing 29 fish species, of which 12 are found inside the BRSM. The River also contains nine species of crustacean, …

Roles Of Religious Orientation And Health Locus Of Control In An Aging Population, Jennifer A. Fallon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An intrinsic religious orientation has been linked to improved cardiovascular health. Individuals may be protected by their beliefs against anger/hostility, which have been linked to increased cardiovascular reactivity and disease. Health locus of control differentiates between internals, who take responsibility for health, and externals, who attribute responsibility to chance or powerful others. Internal health locus of control has been linked to healthy behaviors, but its relationship to religious orientation is unclear.

Intrinsically held religious beliefs and internally held expectancies for health may, through the mechanism of reactivity, reduce risk for cardiovascular disease. This study explored relationships among health …

The Use Of Stress Management In Combination With Parent Training: An Intervention Study With Parents Of Preschool Children, Theresa L. Gunderson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Many preschool children exhibit a number of problematic, acting-out behaviors. Parents of preschoolers exhibiting behavior problems often experience a great deal of stress associated with these problem behaviors. Consistently robust improvements have been found in the use of stress management for adult stress, pain, and medical wellbeing. Likewise, studies have shown parent training decreases the severity of child behavior problems. However, only a few studies have examined effects of parent training on both child behavior and parent stress. Some studies have found that parents who complete parent training also report lowered stress levels commensurate with improvement of child behavior. It …

Greenstrip Establishment And Management In The Intermountain West, Brenda Kristine Younkin-Kury

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Greenstrips were established at two sites in Utah to determine if seeded, grazed cool-season, perennial grasses would change fire behavior characteristics in areas currently dominated by Bromus tectorum. Frequency data were collected for both grazed and ungrazed seeded species and resident weed species. Moderate spring grazing did not negatively impact the establishment of seeded species at Camp Williams. Grazing at Promontory Point decreased Agropyron desertorum frequency and increased the frequency of Pascopyrum smithii. Biomass data collected for grazed and ungrazed treatments in both years indicated that moderate spring or winter grazing the first two years of establishment did …

Cougar Exploitation Levels In Utah: Implications For Demographic Structure, Metapopulation Dynamics, And Population Recovery, David C. Stoner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Presently, eleven western states and two Canadian provinces utilize sport hunting as the primary mechanism for managing cougar (Puma concolor) populations. However, the impacts of sustained harvest on population dynamics and demographic structure arc not well understood. Additionally, the lack of cost-effective enumeration techniques and strongly conflicting societal values complicate effective management of this species. Given these concerns, the primary goals of this study were (I) to determine the effects of sustained harvest on cougar populations, and (2) estimate the level and extent of cougar harvest statewide.

I monitored cougar populations on Monroe Mountain in south-central Utah, and …

Nest Location And Nest Recognition In Two Solitary Bee Species Osmia Lignaria Say And Megachile Rotundata (F.) (Hymenoptera: Megachilidae), Christelle Guédot

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The visual and olfactory cues used in short-range orientation, specifically nest location and nest recognition, were studied in two solitary bee species Osmia lignaria Say and Megachile rotundata (F.) Osmia lignaria, the blue orchard bee, is an important pollinator of orchard crops, such as apples, cherries, and almonds; and M. rotundata, the alfalfa leafcutting bee, is used in commercial pollination of alfalfa. The general objective was to better understand how these two species locate their nests and how improving nest location could benefit crop pollination.

The use of proximal visual landmarks at the nesting site was investigated with …

Natural History, Demography, And Home Range Characteristics Of A Southern California Population Of Phrynosoma Mcallii Inhabiting Atypical Habitat, Kirk Setser

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Phrynosoma mcallii inhabiting a topographically complex, sparsely vegetated, "mudhill" terrain site in southern California in 1999 and 2000 had low mortality rates, and small clutch sizes compared to previous data from this species. Females likely produced a single clutch of eggs in each year. Although this population occurs near a heavily used OHV trail, I did not detect any mortality due to OHV use.

Lizards did not center home ranges on obvious habitat features. Lizards maintained smaller home ranges and exhibited greater range fidelity than did lizards at other sites in other years. Phrynosoma mcallii share many area-use characters with …

Feeding Behavior Of Sheep In Relation To Kinetics Of Sagebrush Monoterpenes: Implications For Landscape Biodiversity, Luthando E. Dziba

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The sagebrush steppe is one of the most extensive vegetation types in the western US and an important habitat for wild and domestic herbivores. When sagebrush dominates, however, forage and habitat quality decline. Although sagebrush is nutritious, its forage value is reduced by terpenes. A better understanding of how terpenes limit intake is vital for increasing consumption of sagebrush and for enhancing and maintaining biodiversity in the sagebrush-steppe.

To better understand how terpenes in sagebrush limit intake, we studied feeding behavior of sheep in the field, influence of sagebrush monoterpenes on regulation of intake in pens, and the feeding behavior …

Host Shifts In Phytophagous Insects: A Mathematical Modeling Perspective, Meenakshi Venkataraman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I explored changes in predator-prey system stability with the addition of spatial heterogeneity in prey density dependent mortality. The results indicated that this addition led to greater stability for all prey spatial distributions if prey was aggregated or loosely aggregated. These results indicated prey spatial distribution was critical to population stability. I next explored whether predator emigration under the above conditions would lead to a host shift. I used Chesson and Murdoch's templates of host density independent (HDI) aggregation and host density dependent (HDD) aggregation in predators as the basis for my metapopulation models. I varied prey density dependent mortality …

Changes In Child Symptomatology Associated With Animal-Assisted Therapy, Catherine C. Woolley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined the changes in symptoms of anxiety, depression, and social dysfunction associated with a history of child trauma after adding animal-assisted therapy (AAT) to conventional psychotherapy for adolescents living in a residential treatment facility in northern California. Using a quasiexperimental design, participants were followed over a period of nine weeks, with both groups completing the State-Trait Anxiety Inventory, the Beck Depression Inventory, an abbreviated version of the Beck Depression Inventory, and the Youth Self-Report, and residential staff completing the Youth Outcome Questionnaire at three time points. In addition, the treatment group completed state anxiety and depression assessments before …

Rapid Effects Of 25-Hydroxyvitamin D3 On Calcium Uptake In Isolated Chick Enterocytes, Ruta Phadnis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

25-Hydroxyvitamin D₃[25(OH)D₃] is a metabolite of vitamin D₃ that has long been considered to be an inactive precursor of the hormonally active metabolite 1,25- dihydroxyvitamin D₃[l,25(OH)₂D₃]; consequently very few studies have addressed the potential biological activity of 25(OH)₂D₃. However, it is known that 100 nM 25(OH)₂D₃ increases calcium transport in the perfused duodenal loop of the chicken to 200% of controls within 20 minutes. The hypothesis of the current study is that 25(OH)₂D₃ may be a hormonally active metabolite …

Adolescent Peer Perceptions Reflected In The Yearbooks Of Mormon Homosexual And Heterosexual Men, David C. Pruden

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study explored the peer perceptions of adolescent heterosexual males and their homosexual counterparts who had not disclosed their feelings of erotic same-sex attraction to their classmates. The study focused on members of The Church of Jesus Christ of Latter-day Saints, a conservative Christian denomination with clear doctrinal prohibitions against homosexual behavior. The handwritten messages from peers found in the senior high school yearbooks of 30 heterosexual and 30 same-sex attracted adolescent men were content analyzed to examine similarities and differences in the themes that emerged from the data.

The results indicated that there is a difference in the kind …

Rapid Detection Of Listeria Monocytogenes, Wim Lippens

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Listeria monocytogenes is a foodbome pathogen that can cause severe illness and even death. It is found in dairy and meat products. The focus is on rapid detection since conventional methods are time consuming (4-5 days). Pre-enrichment steps, as part of those methods, are time consuming. Our objective was to develop a detection system without a pre-enrichment step, giving a final result within 2 to 4 h.

In the concept of "the need for speed," a detection system with an antibody-based capture technique, followed by polymerase chain reaction (PCR), was developed. Glass beads coated with a Listeria polyclonal antibody were …

An Ecological/Life History Comparison Of Two Whitefish Species In Bear Lake, Utah/Idaho, Brett W. Thompson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ecological traits of the endemic Bear Lake whitefish Prosoopium abyssicola and the Bonneville whitefish prosopium silonotus were investigated. Spatial distributions indicated distinctive differences in depth contour preference. Catch per unit effort data indicated that Bonneville whitefish prefer shallow depths and warmer water temperatures, whereas Bear Lake whitefish prefer deep, cold water.

Diet differences between the two species were large. Differences in both age distribution and growth rate patterns were also observed. The Bonneville whitefish population was predominantly composed of juvenile age classes. Very large adults reached ages of 12-14 years. Bear Lake whitefish exhibited a different population structure with few …

Assessing The Effects Of Myxobolus Cerebralis And Other Environmental Factors On The Dynamics, Abundance, And Distribution Of Trout Populations In The Logan River, Utah, Ernesto A. De La Hoz Franco

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The presence of nonnative trout and the recent introduction of Myxobolus cerebralis in the Logan River drainage pose a threat to the native Bonneville cutthroat trout population (Oncorhynchus clarki Utah). The variability in the response of susceptible trout populations to M. cerebralis, causing agent of whirling disease, suggests that environmental factors may influence the effects of the parasite in infected environments. I investigated the relationship between temperature, discharge, substrate size, nutrient concentration (nitrogen and phosphorus), periphyton (chlorophyll a), and the relative abundance of Tubifex tubifex to the distribution, and prevalence of M. cerebralis in wild salmonid populations and …

Foraging Behavior And Habitat Use Patterns Of Brown Bears (Ursus Arctos) In Relation To Human Activity And Salmon Abundance On A Coastal Alaskan Salmon Stream, Anthony P. Crupi Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Over the past decade, demand for recreation has increased as part of Alaska's doubling growth in tourism. Along the Chilkoot River, near Haines, fishing and bear viewing have become increasingly popular. I investigated the ecological and behavioral interactions there between brown bears, salmon, and humans between 2000 and 2002. My objectives were to: (1) determine if specific human activities differentially influenced bear activity and foraging behavior, (2) identify temporal and spatial habitat use patterns, (3) evaluate brown bear response to natural and human disturbances and quantify related flight distances, (4) investigate changes in bear foraging behaviors in response to prey …

Modeling Habitat Quality For American Martens In Western Newfoundland, Canada, William A. Adair

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The "Den Mother" marten habitat quality models were created to provide insight into American marten habitat selection behavior and to promote the recovery of the Newfoundland marten (Martes americana atrata) population. Although these objectives are typical of most wildlife habitat modeling projects, the marten's idiosyncratic habitat ecology and apparently intractable conflicts associated with timber harvesting motivated a unique, process-oriented approach to appraising landscapes. The Den Mother models used optimal decision-making principles to synthesize critical resources (den sites and foraging opportunities) and constraints (adverse thermal situations and exposure to predations) into a single hierarchical framework. The resulting spatially explicit, …

Determining The Factors That Control Respiration And Carbon Use Efficiency In Crop Plants, Jonathan M. Frantz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the literature on plant respiration, there are two viewpoints concerning the source of respiratory control: supply (photosynthate availability) or demand (temperature dependent) limitations. While different studies indicate the primary dependency for respiration is either the supply or demand side, the two paradigms cannot both be true. The relative importance of each paradigm may depend on a number of factors including period of time during which respiration is measured, phase of plant development, environmental conditions, and species.

Studies were performed using continuous CO₂ gas-exchange instrumentation to monitor short- and long-term changes in whole canopies of lettuce, tomato, soybean, and …

Breeding Bird Communities Of Major Mainland Rivers Of Southeastern Alaska, Jim A. Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Because of the scarcity of information for bird communities at the major mainland rivers of southeastern Alaska, the main objective of this study was to provide baseline information including distribution, status, and habitat associations of breeding birds.

I conducted a meta-analysis of all known reports (including the current study) conducted at major mainland rivers during the breeding season. I described bird species composition, distribution, abundance estimates, status, habitat associations, and guild membership for all birds recorded at 11 major mainland rivers. Based on incidental observations, 170 species were recorded by all studies. Of these, 134 species were known or suspected …

Outcomes And Presurgical Correlates Of Lumbar Interbody Cage Fusion, Rick Lacaille

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rates of lumbar fusion surgery have been increasing with an estimated 192,000 procedures performed annually. However, satisfactory outcomes of lumbar fusion vary considerably and often emphasize technical success, such as arthrodesis, rather than Ill functional and quality of life outcomes. Interbody cage fusion was recently developed and touted as a superior alternative to existing lumbar fusion procedures. There is, however, a paucity of research to support these claims, particularly with regards to functional and quality of life outcomes. Moreover, predictive correlates of outcomes for interbody cage fusion have not been given adequate attention in the literature. The aims of this …

The Foraging Behavior Of A Solitary Bee, Diadasia Nigrifrons (Hymenoptera: Anthophoridae) On Sidalcea Oregana, Ssp. Oregana, Kimberly A. Kuta

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Foraging studies have established that bees typically obey a set of movement rules when foraging on vertical inflorescences: they begin foraging at the bottom of an inflorescence, move upward, visit a fraction of the available flowers, and leave before reaching the top of the inflorescence. These behaviors are purported to maximize bee foraging efficiency by concentrating their efforts on the most rewarding flowers and minimizing flower revisits. Bees also increase their efficiency by selecting inflorescences with many flowers, visiting more flowers per inflorescence, and remaining in resource-rich areas. To test these hypotheses on plants with more complicated flower arrangements, I …

Simulation Of Wind Dispersal Of Tree Seeds, Tree Colonization, And Growth Of Bottomland Hardwood Reforestation Sites Of The Mississippi Alluvial Valley, Timothy James Nuttle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tree community composition in bottomland hardwood reforestation sites is considerably less diverse than natural bottomland hardwood forests. This study sought to understand the mechanisms behind failure to develop diverse tree communities. First, I developed a mechanistic model of seed dispersal by wind in spatially variable environments. Second, I developed a spatially explicit simulation model of forest dynamics that includes this wind-dispersal model to investigate whether diversity is limited by dispersal or interactions among species and individuals. Finally, I performed model experiments to determine if manipulations of stand structure might help improve conditions for colonization of various species, thus enhancing diversity …

Species Pairwise Associations Over Nine Years Of Secondary Succession: Assessing Alternative Explanations And Successional Mechanisms, Lara R. Rozzell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The importance and mechanisms of species interactions are undetermined in most successional systems. I used correlations and null modeling to detect pairwise species associations between 33 plant species in the first nine years of secondary succession after logging and burning in a western Oregon Cascade forest. I tested for correlations between each species and soil nutrients, nonvegetative ground cover, and surrounding vegetation. More positive than negative associations were found at all sampling times. The proportion of positive associations decreased and negative associations increased through time. Up to 42% of associations at a sampling time were explicable by shared positive correlations …

Catastrophic Wildfire Hazard Assessment In Pinyon-Juniper Woodlands Utilizing A Managerial Paradigm, Benjamin D. Baldwin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The impetus for this research was the increasing threat of catastrophic wildfires resulting from the accumulation of fuels across the West. Guided by the priorities, goals, and guiding principles outlined by the national fire plan (NFP), the objective was to identify those areas within a pinyon-juniper woodland-dominated landscape with the highest hazard of catastrophic wildfire. The intent was to help managers prioritize proactive fuels management efforts outside of the wildland urban interface (WUI). Based on a management paradigm, constraints were placed on the data collection, analysis, and model development. A geographic information system (GIS) was used to create a hazard …

Using Immune Modulators To Ameliorate Aleutian Disease In Mink, Kie Hoon Jung

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Aleutian disease of mink (AD) is an immunopathological disorder induced by persistent infection with AD virus. Many breeds of mink seem to have a high susceptibility to AD. Interestingly, the primary feature of AD in susceptible adult mink is a chronic, fatal immune complex-mediated glomerulonephritis comparable to that seen in human diseases such as systemic lupus erythematosus. Because of its comparative aspects to human diseases and the substantial economic loss to the fur industries in the world, classical AD and the nature of the virus has been studied extensively for three decades. Currently no therapies are available and vaccination has …

Nature Writing And Healing: Recovering The Wild Soul, Denice H. Turner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In this study, I explored how nature writing could be seen as healing text. I described some common problems associated with the construction of trauma and grief narratives and examined how nature writers dealt with them. The study began with my frustration at being unable to write a healing narrative for myself and progressed as I integrated research that informed my own writing.

The literature I read included a variety of perspectives, from Jungian and traditional psychotherapy to current writing theory. I used the theory to comment on the nature writing texts as I discovered them. Using the words and …

The Influence Of Predator Exclosures And Livestock Grazing On Duck Production At Bear River Migratory Bird Refuge, Utah, Benjamin C. West

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nest predation is a major factor impacting duck production and recruitment on breeding areas in North America. I surveyed waterfowl managers employed by the U.S. Fish and Wildlife Service and U.S. state wildlife agencies to determine their beliefs about nest predation and its management. Over 64% of respondents believed that rates of nest success on their management units averaged < 30% between 1996-2000. Managers believed habitat management and direct predator control were the most effective techniques to reduce nest predation. The construction of predator ex closures around nesting habitat also has been recommended to reduce nest predation. Between 1999-200 I, I evaluated the effectiveness of 4 predator ex closures to enhance duck nest success at Bear River Migratory Bird Refuge, Utah. During this period, rates of nest success in the exclosures were slightly higher than that within control plots, but still < 15%. Although published guidelines commonly recommend predator fences < 117 cm in height, I observed red foxes jump the 11 4-cm-high fences. Additional research is needed to identify effective predator fence designs.

Wildlife managers have argued that periodic disturbance of vegetation should be a component of management on waterfowl breeding areas. Although many techniques are available to manipulate vegetation, grazing by domestic livestock has been controversial. Some researchers have reported that livestock grazing …

Effects Of Myxobolus Cerebralis On The Population Dynamics Of Kokanee In Porcupine Reservoir, Utah, Arthur E. Butts

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study tracked the chronology and severity of Myxobolus cerebralis infection and related it to survival of age-0 kokanee to determine whether M. cerebralis represented a significant agent of morality in the population. Environmental conditions and losses to predation were identified and linked to age-0 kokanee survival to identify other sources of mortality in the population. We attempted to track survival of age-0 kokanee from the outmigration into the reservoir until the end of the first growing season in September of each year. The number of age-0 kokanee that entered the reservoir was calculated by obtaining estimates of total egg …

Coyote Foraging Ecology, Vigilance, And Behavioral Cascades In Response To Gray Wolf Reintroduction In Yellowstone National Park, T. Adam Switalski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Vigilance behavior can aid in the detection of predators and may also play a role in observation of conspecifics, in food acquisition, and in the prevention of kleptoparasitism. However, in most occasions, vigilance is most important as an antipredator function. Generally, factors that increase the risk of predation also increase the amount of vigilance. We examined whether the reintroduction of the large predator, the wolf, in Yellowstone National Park (YNP) would influence coyote vigilance and foraging ecology. From December 1997 to July 2000, we collected 1743 h of coyote activity budgets. Coyote home ranges occurred within wolf territories (termed high-use …

Concurrent And Construct Validity Of Alternating Verbal Fluency As A Measure Of Executive Function, Gail A. Mason

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Alternating verbal fluency is a combination task that was designed to assess the cognitive constructs of verbal fluency and cognitive shifting, presumably for increased efficiency. Researchers and clinicians have hypothesized about the added diagnostic benefits and more sophisticated discriminability of alternating verbal fluency as compared with singular verbal fluency tasks.

To date there are no standardized forms of alternating verbal fluency tests, normed data, or a guide for differentiating patient populations. In addition, there are no published studies addressing the construct or concurrent validity of alternating verbal fluency with other tests of executive function. Thus, the purpose of the present …