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Aromatic Amino Acid Catabolism By Lactobacillus Spp.: Biochemistry And Contribution To Cheese Flavor Development, Sanjay Gummalla

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Amino acids derived from the degradation of casein in cheese serve as precursors for the generation of desirable and undesirable flavor compounds. Microbial degradation of aromatic amino acids is associated with the formation of aroma compounds that impart putrid-fecal, barny-utensil, and floral off-flavors in cheese, but pathways for their production had not been established. This study investigated Tyr and Phe catabolism by Lactobacillus casei and Lactobacillus helveticus cheese flavor adjuncts under simulated Cheddar cheese-ripening conditions (pH 5.2, 4% NaCl, 15°C, no sugar). Enzyme assays of cell-free extracts and micellar electrokinetic capillary chromatography of supernatants indicated that L. casei and L. …

Rapid Actions Of 1,25-Dihydroxyvitamin D3 On Phosphate Uptake In Isolated Chick Intestinal Cells, Bin Zhao

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

1,25-dihydroxyvitamin D₃ [1,25(OH)₂D₃] has been shown to promote phosphate transport rapidly in the perfused duodenal loop, relative to controls, reaching treated/av basal at T = 40 min = 1.82 ± 0.42 and 1.11 ± 0.21, respectively.

By using isolated chick enterocytes, studies were undertaken to determine whether 1,25(OH)₂D₃ has a direct effect on isolated intestinal cells that is manifested by either enhanced uptake or extrusion of phosphate.

In time course studies, with 4- to 8-wk-old chicks, ³²P uptake in enterocytes at 10 min after addition of test substance was 0%, 130%, …

Dietary Protein Intake As Measured By A Picture-Sort Food Frequency Questionnaire And Risk Of Osteoporotic Hip Fracture In Aging Residents Of Utah, Heidi Jensen Wengreen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Protein is an important component of bone, but the role of dietary protein intake in osteoporosis remains controversial. The Utah picture-sort food frequency questionnaire was found to produce a useful estimation of usual dietary intake in the elderly. This method of dietary assessment was used in a population-based case-control study to examine the relationship between protein intake and risk of osteoporotic hip fracture in elderly Utah residents. Analyses of risk of hip fracture across increasing quartiles of protein intake were stratified by age-group. Higher protein intake was associated with a reduced risk of hip fracture in men and women aged …

Physiological Importance Of 1,25(Oh)2D3 Membrane-Initiated And Nuclear Actions In Chickens As A Function Of Growth, And Maturation In Male And Female Chickens, Birgitta Larsson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

It is well established that l,25(OH)₂D₃ is a major regulator of calcium homeostasis. The steroid exerts its effects on its target organs by two mechanisms, a slow mechanism mediated by nuclear vitamin D receptors (nVDR), and a rapid mechanism mediated by the l,25(OH)₂D₃ membrane-associated rapid response steroid binding protein (l,25D₃-MARRS bp). In this dissertation, the physiological relevance of membrane initiated steroid signaling was investigated by studying the correlation of age in male and female chickens with the magnitude of responses to l,25(OH)₂D₃ in duodena from 7-, 14-, 28-, and …

Factors Affecting The Harvest Vulnerability Of Trumpeter Swans, Heidi L. Tangermann

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two species of swan are regularly found in Utah, tundra swans (Cygnus columbianus) and trumpeter swans (Cygnus buccinator). Tundra swans migrate through Utah. During the fall migration period they are hunted in the state under guidelines established by the United States Fish and Wildlife Service (USFWS). Trumpeter swans are occasional visitors to Utah during the same migration period. Because trumpeter swans are difficult to distinguish from tundra swans in flight, they 11 are at risk of being harvested during the swan hunt. In my thesis, I examine the factors that may influence trumpeter swan vulnerability to …

Application Of Biophysical Data To An Unsupervised Classification To Map Ecoregional Boundaries In The Desert Southwest, Paxton R. Mcclurg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An unsupervised classification was applied to continuous biophysical variables in an attempt to delineate ecoregional boundaries in the desert southwest. Output was then compared with ecoregions delineated by the Natural Resources Conservation Service (NRCS), the Environmental Protection Agency (EPA), and the Forest Service at the national level. An attempt was made to use the same biophysical variables for input into the unsupervised classification as was emphasized by the various agencies with their ecoregional classifications at the desert level. Major constraints included data availability at such a large study area, data resolution, and data that were continuous. This eliminated categorical data …

Effects Of Physical Activity And Religiosity On Psychophysiological Reactivity In An Aging Population, Tera L. Lensegrav Benson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Physical activity is known to offer health benefits. Additionally, research has linked religious involvement with health. Psychophysiological reactivity has links to coronary heart disease. This study examines the relationship between physical activity and religiosity in light of psychophysiological reactivity. The sample included 75 subjects, with a mean age of 71. 7 (SD = 6.11 ), with no history of cardiac incident. Religiosity was measured with the Religious Orientation Scale (ROS). Physical activity was assessed utilizing the Typical Week Physical Activity Scale. Psychophysiological reactivity was measured by blood pressure, heart rate, and self-report anger ratings in response to interpersonal challenge. …

Identifying The Bases For Gender Differences In Guilt And Shame, R. Shawn Edmondson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Gender differences are frequently revealed on the popular TOSCA-2 measure of guilt- and shame-proneness. These gender differences could reflect biases in the eliciting conditions that participants evaluate and confounds between them. A new instrument, the Gender Relevant Test of Self-Conscious Affect (GR-TOSCA), was developed to eliminate these confounds, thereby introducing a gender-sensitive, and therefore more valid, measure of guilt and shame proneness. The psychometric integrity of the new instrument, hypotheses regarding condition-specific gender differences in the two emotions, and relationships of guilt- and shame-proneness scores to gender role endorsement were examined in a sample of undergraduate students (93 men and …

Stratigraphy And Paleoecology Of The Morrison Formation, Como Bluff, Wyoming, Melissa V. Connely

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Morrison Formation at Como Bluff, Wyoming, has been historically known for containing a rich source of Late Jurassic vertebrate fossils. However, when collected, most of these fossils were not positioned into a stratigraphic or sedimentologic framework. Research shows that the Morrison Formation at Como Bluff can be divided into three members. These members can be identified by lithologic and paleontological characteristics. The lower Morrison members include the Windy Hill Member and the recently described Lake Como Member. The Windy Hill Member primarily contains near-shore marine sandstone. Megavertebrate fauna is lacking. The Lake Como Member contains illitic clay in red …

A Conceptual Model To Characterize Internal Structure Of Plant Communities Based On Functional Traits In Camp Williams, Utah, And Camp Grayling, Michigan, Patricia Hernandez De La Rosa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

How plants from a common species pool form community has been considered from a variety of approaches. A promising approach involves the search for assembly rules based on plant functional traits. This approach has potential to provide insight into community and ecosystem processes In this research. a general and simple conceptual model based on life forms and independent of species is used as a framework for assessing the internal structure of plant communities. Plant functional traits are used to identify patterns within and between plant communities in the contrasting environments of Camp Williams, Utah, and Camp Grayling, Michigan.

The conceptual …

Analyses Of Diet And Geographic Variation In Leaf-Nosed Snakes, Phyllorhynchus, Stephanie A. Gardner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study revealed that P. decurtatus primarily eat squamate eggs, and that the diet of P. browni appears to consist entirely of squamate eggs; gecko tails constitute a very small proportion of the diet of P. decurtatus. Feeding in both species occurred throughout their active seasons and both species increased prey consumption in August. The sexes of P. browni, but not P. decurtatus showed different monthly feeding patterns. Desert-of-collection did not affect P. decurtatus monthly feeding patterns. Phyllorhynchus decurtatus collected from the Sonoran Desert and P. browni, which is found only in the Sonoran Desert, showed similar …

Patterns And Processes Of Population Differentiation In The Chuckwalla (Sauromalus Obesus) In Southern Nevada, Paul C. Ustach

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I examined both present-day and historical patterns in the herbivorous desert lizard, Sauromalus obesus (chuckwalla), within the Mojave Desert ecoregion in Nevada. My goal was to determine the process or processes that led to their present-day distribution. I expected to recover distinct haplotypes unique to each mountain range. These unique haplotypes were expected to reveal a pattern of geographic partitioning with sequence divergence among populations increasing as a function of distance. I characterized the distribution of chuckwallas in Nevada by means of a simple model using a geographic information system (GIS). This simple model was used to enhance sampling efficiency …

The Role Of Brown Bears (Ursus Arctos) In Nutrient Transport Into Forests Near A Salmon Stream In Coastal British Columbia, Canada, Arthur Morris

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nutrients from spawned salmon contribute to the fertility of rivers and riparian areas. Adjacent forests, even far from rivers, could receive substantial amounts of nitrogen and other nutrients from salmon. Since brown bears feed heavily on spawning salmon, bears probably influence the movement of nutrients from salmon into surrounding forests. Because salmon-derived nitrogen is high in ¹⁵N, increased isotopic enrichment is expected in forest soils and vegetation if this transport is occurring. Based on relative ¹⁵N enrichment of spawning areas, a quantitative estimate of marine-derived nitrogen (MDN) can be obtained using a linear two-source mixing model. To evaluate …

The Role Of The Arabidopsis Phosphatidylinositol 3-Kinase In Vacuolar Protein Transport, Christopher A. Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In all eukaryotic organisms vesicle-mediated protein transport is crucial for maintaining cellular homeostasis. Over the past decade significant strides have been made in elucidating the molecular mechanisms governing this complex process. Both genetic and biochemical studies have demonstrated the unequivocal involvement of class III phospatidylinositol 3-kinases (PtdIns 3-kinases) in regulating vesicle transport. While PtdIns 3-kinases have been well studied in both yeast and mammalian systems, the role of these enzymes in plants is poorly understood. In the present study, we demonstrate that the Arabidopsis Ptdlns 3-kinase is localized to the cytoplasm, and perhaps the Golgi apparatus. Moreover, we show that …

The Development Of A Bluetongue Virus Diagnostic Assay Using Peptides Derived From The Structural Protein Vp7 And Nonstructural Protein Ns2, Yi Lu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Several peptides derived from viral proteins, VP7 and NS2 of bluetongue virus (BTV), were synthesized for an immunologic detection assay: distinguishing between bluetongue virus infected, vaccinated, and noninfected animals (ruminants) with dot blot analysis. The School of Veterinary Medicine, University of California, Davis, supplied the serum samples from 24 bovine, 18 caprine, 23 ovine. Another 205 bison serum samples were obtained in Utah. The serum samples of BTV-infected animals revealed detectable antibodies to both VP7 and NS2 peptides, whereas vaccinated animals only exhibited antibodies against VP7. Noninfected animals did not display antibody against either viral peptide. These data confirmed the …

Movement Patterns Of Phrynosoma Mcallii And Phrynosoma Platyrhinos In Response To Substrate Texture, Daniel H. Foley Iii

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During the summers of 1999 and 2000 the apparent habitat partitioning of two species of sympatric horned lizards was investigated at the Barry M. Goldwater Bombing Range near Yuma, Arizona. The flat-tailed horned lizard, Phrynosoma mcallii, and the desert horned lizard, P. platyrhinos, overlap in range in portions of the Sonora desert in the southwestern United States. However, upon finer scale examination, it appeared that these horned lizards were partitioning the available habitat according to soil substrate texture. Phrynosoma mcallii appeared to be exclusively found in areas of fine, loose, wind-blown sands, in contrast to P. platyrhinos, …

Adoption Of Range Management Innovations By Utah Livestock Producers, Elizabeth Anne Didier

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Recent years have seen changes in ecological conditions, ownership patterns, and political-legal forces that affect the sustainability of Western range livestock production. Enterprise diversification and implementation of improvements are advocated as ways for ranchers to cope with marginal returns from ranching while better managing resources. However, relatively few ranchers make such substantive changes in their operations, and previous research suggests that rates of adoption may be especially low in Utah.

Using a qualitative approach, this study explored innovation adoption among Utah ranchers. During preliminary interviews with 13 key informants, commitment to traditional ranching lifestyles, the state's settlement pattern, and availability …

Ecology Of Treeline Whitebark Pine (Pinus Albicaulis) Populations In Central Idaho: Successional Status, Recruitment, And Mortality, And A Spring Temperature Reconstruction From Whitebark Pine Tree Rings, Dana Lee Perkins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research investigated the successional status of treeline whitebark pine (Pinus albicaulis) populations on 14 stands in central Idaho and used empirical statistical models to determine the principal factors affecting recruitment and mortality. The longest lived whitebark pines from four additional high-elevation sites were used to develop a tree-ring chronology to reconstruct over 1,000 years of average April-May temperature.

The assessment of stand structures using size-frequency distributions generally provides evidence that treeline whitebark pine populations are currently self-sustaining in areas of low to nonexistent incidence of white pine blister rust (Cronartium ribicola). However the presence of …

Recreation, Livestock Grazing, And Protected Resource Values In The Grand Staircase-Escalante National Monument, Lael Palmer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis reports the results of a project which identified differences in characteristics of Grand Staircase-Escalante National Monument user groups as they related to their perceptions of how they experience the Monument as recreationists. It explored opinions of four groups: hikers vs. hunters and pre-designation users vs. post-designation users. Responses of these groups were compared for attribution of perceived resource damage, feelings of crowding, acceptability of management action, and importance of identified monument values to their visit. In addition, characteristics of the users were examined to determine if demographic characteristics accounted for differences in perception toward the resources. Finally, how …

Development Of A Bird-Avoidance Model For Naval Air Facility El Centro, California, Edward J. Zakrajsek

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bird strikes (collisions between birds and aircraft) pose a significant threat to aviation safety. For example, Naval Air Facility El Centro, California, lost an F-18 jet to a bird strike in October 1995. To help combat the bird-strike threat at Naval Air Facility El Centro, I developed a bird-avoidance model as a risk-management tool for the installation. It can be used to schedule flights at NAF El Centro and its two associated practice-bombing ranges during times of low-bird activity. I calculated bird-strike risks and published them in web-page format on both the installation's server and the USGS/Utah State University, College …

Juvenile Females Who Sexually Offend: A Beginning Typology, Jason M. Nelson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was broken into two sections, the first being a comprehensive meta-analysis describing a profile of the juvenile female who sexually offends. The second section was the collection of data of juvenile females who sexually offend in the State of Utah. After the data were collected, a profile was described and compared to that found in the Review of the Literature and a typology was presented.

Ecosystemic legacies were shown to be passed down from one generation to the next. The juveniles were found to come from highly chaotic homes, and subject to maltreatment. Diagnostically, they show symptoms of …

Benthic Invertebrate Assemblage Structure In Mountain Streams: The Influence Of Spatial Scale Of Observation And Organism Size On Relationships With Environmental Factors, James N. Hogue

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The description of pattern in nature depends on the size and scale of both the observer and the phenomena being observed. The relative influence that different environmental factors have on organism distributions depends not only on scales of variation inherent to each factor, but also on the size and scale of the organisms. 

I used data from 649 sites within 45 mountain streams in California to quantify relationships between environmental factors and organism distribution. I compared these relationships across analyses conducted at different spatial and biotic scales of resolution. I also examined relationships between environmental variation and assemblage size structure …

Energy, Fractal Movement Patterns, And Scale-Dependent Habitat Relationships Of Urban And Rural Mule Deer, Mark F. Mcclure

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I studied the behaviors, movement dynamics, habitat relationships, and population characteristics of Rocky Mountain mule deer (Odocoileus hemionus) using urban and rural winter ranges in Cache Valley, Utah, from January 1994 to February 1998. There were 2 goals to my research endeavors. The first was to assess how and why the behaviors and demographic characteristics of urban deer differed from those of rural deer. The second was to assess the scale-dependent responses to habitat and the scale-dependent patterns of habitat use by deer living in each area. To accomplish the first goal, I compared the prevalence of migration, the spatial …

Reproductive Allocation And Survival In Grasshoppers: Effects Of Resource Availability, Grasshopper Density, And Parasitism, David Heath Branson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A major challenge in ecology is to understand intraspecific variation in life histories. Variation in resource availability can lead to differences in reproductive allocation and life histories. Grasshoppers are a good organism for the study of variation in life histories, since they exhibit life history plasticity in response to biotic and environmental factors. An optimality model for grasshoppers was developed that predicts optimal total allocation to reproduction and optimal effort-per-offspring as functions of resource availability and mortality. Relative allocation to reproduction is predicted to increase with resource availability, while relative allocation to survival declines. A resource-based trade-off between egg size …

Rangeland Resources Monitoring: Concepts And Practical Applications, Benny R. Bobwski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

How does one person manage and monitor a half million acres of rangelands towards a sustainable future? Through a journey that begins with the understanding of sustainability, I explore the monitoring concept, two of its applications, and summarize with an emphasis on the art and science of management. Sustainability is a concept that confuses many managers because it is so complex. However, if one considers adaptability as the complement to sustainability, and realizes that an adaptable organism is a sustainable organism, then a manager can relate because the emphasis shifts from that of stability for the future to that of …

The Efficacy Of Plant Residue Degradation Products On Phosphorus, Iron, Iodine, And Fluorine Bioavailability To Plants, Cheryl L. Mackowiak

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plant and animal wastes degrade in soils to form relatively stable humified compounds, which form ion complexes that affect the bioavailability of elements in the soil solution. Hydroponic studies with wheat and rice were conducted to characterize the effect of humic acid (HA) on phosphorus (P), iron (Fe), fluorine (F), and iodine (I) bioavailability. Ferrihydrite [Fe(OH)₃] precipitation was greater on root surfaces without HA or synthetic chelates. Oxides such as ferrihydrite strongly adsorb P and provide exchange sites for metals. HA reduced this precipitate and increased P and Fe uptake.

Humic acid had no effect on F toxicity …

Establishing Reinforcing Properties In Neutral Stimuli Through Observational Learning With Children, Andrew Waine Gardner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to observe and analyze the factors that lead to a child's increase in responding to a previously neutral stimulus after observing another child's behavior and consequences in the same setting. The effects of five video presentations on rate of button-pressing responses were observed across four students. Rates of button-pressing behavior on an FR3 schedule of reinforcement were collected for each student using a computer and a metal apparatus with two flat push buttons. Each student completed two baseline phases to establish neutrality of stimuli, and viewed a total of five video presentations. Each video …

Psychosocial Factors And Their Relationship To Type-2 Diabetes Mellitus Outcome Among The Strong Heart Study Cohort, Brian O'Leary

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Diabetes mellitus is a serious problem that affects 15.7 million individuals in the United States. The complications of this disease are catastrophic and can lead to blindness, kidney disease, lower limb amputations, nerve damage, increased risk of heart disease, stroke, and death. Among Native Americans, diabetes has reached epidemic proportions. A variety of psychosocial variables has demonstrated relationships to diabetic outcome. Past research has shown a relationship between psychological variables and glucose control. The current study of Native Americans shows a similar pattern using the psychosocial instruments to measure the constructs of depression, anger, hostility, social support, and perceived stress. …

A Longitudinal Study Of Attention-Deficit/Hyperactivity Disorder Symptoms In Preschool-Age Children, Jessica Nicole Greenson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Attention-deficit hyperactivity disorder (ADHD) is among the most common reasons for referral to children's mental health clinics, with an estimated prevalence of 3% to 5% in the general population of school-age children. Children who exhibit the requisite behaviors may obtain a diagnosis of ADHD at any age; however, symptom onset must occur before age 7 and persist for at least 6 months. Despite these temporal requirements for diagnosis, little empirical information about the manifestation and stability of ADHD symptoms in preschool children exists. This study provides information about the initial presence and stability over one academic year of ADHD behaviors …

Effectiveness Of Earthen Escape Ramps In Reducing Big Game Mortality In Utah, Mary L. Hammer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

One-way escape gates and earthen escape ramps are structures used to enable deer to exit the highway right-of-way along fenced roads. I compared the use of one-way escape gates and earthen escape ramps by mule deer on two highways in Utah to determine if deer exhibited a preference for either structure. Results showed that earthen escape ramps were used by mule deer 8-11 times more frequently than one-way gates. Highway mortality data suggest that the installation of the escape ramps likely reduced mortality of mule deer in both study locations, because we could not attribute reductions in mortality to decreased …