Life Sciences Commons^™

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 …

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, …

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 …

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 …

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 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 …

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 …

Seasonal Movements Of Fluvial Bonneville Cutthroat Trout In The Thomas Fork Of The Bear River, Idaho-Wyoming, Warren Colyer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The majority of interior cutthroat trout (Oncorhynchus clarki) subspecies have been extirpated from large rivers by anthropogenic activities that have fragmented habitats and introduced non-native competitors. Selective pressures against migratory behaviors and mainstream river occupation and conservation schemes that isolate genetically pure populations above barriers have restricted gene flow and prevented the expression of fluvial life history traits in many populations. Existing knowledge about the movements and home range requirements of fluvial cutthroat trout is therefore limited. We implanted a total of 55 Bonneville cutthroat trout (BCT) in the Thomas Fork River, Idaho, with radio transmitters and located …

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 …

Evapotranspiration Using A Satellite-Based Surface Energy Balance With Standardized Ground Control, Ricardo Trezza

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study evaluated the potential of using the Surface Energy Balance Algorithm for Land (SEBAL) as a means for estimating evapotranspiration (ET) for local and regional scales in Southern Idaho. The original SEBAL model was refined during this study to provide better estimation of ET in agricultural areas and to make more reliable estimates of ET from other surfaces as well, including mountainous terrain. The modified version of SEBAL used in this study, termed as SEBAL_ID (lD stands for Idaho) includes standardization of the two SEBAL "anchor" pixels, the use of a water balance …

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 …

Affinity Purification And Characterization Of E. Coli Molecular Chaperones, Seung-Hee Nam

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The molecular chaperones are a group of proteins that are effective in vitro and in vivo folding aids and show a well documented affinity for proteins lacking tertiary structure.

Heat-induced Escherichia coli BL21 cell lysate (10 mg protein) was applied to immobilized ɑ-casein (45 mg/g beads) or β-casein (30 mg/g beads) column. After removing a majority of nonspecifically bound proteins with 1 M NaCl, the molecular chaperones were eluted with cold water, 1 mM Mg-ATP, or 6 M urea. Western analysis identified five Escherichia coli molecular chaperones including DnaK, DnaJ, GrpE, GroEL, and GroES. Among samples, ATP eluates showed the …

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 …

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 …

Effect Of Chemical Parameters On Structure-Function Relationships Of Cheese, Andres J. Pastorino

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effect of chemical parameters on cheese structure and functionality was studied by modifying the calcium, salt content, and pH of cheese. Cheese blocks were high-pressure injected from zero to five times with water, solutions of different salts, or an acid solution 14 d after manufacture. Successive injections were performed 24 h apart. After 40-42 d of refrigerated storage, cheese structure was studied by using scanning electron microscopy and digital image analysis, and cheese functionality was characterized by texture profile analysis and melting test.

Increased salt content of cheese (2.7 versus 0.1%) caused the protein matrix to become more hydrated …

Statmod: A Tool For Interfacing Arcview® Gis With Statistical Software To Facilitate Predictive Ecological Modeling, Christine M. Garrard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As geographical information systems and spatial data become more accessible, predictive spatial modeling in ecology is becoming more common. Unfortunately, not all ecologists possess the necessary skills to successfully combine statistical models and geographical information systems. In response to this problem, I wrote an extension for ArcView^® GIS called StatMod. This extension interfaces ArcView GIS with SAS^® and S-PLUS^® statistical software and walks the user through creating and mapping logistic regression and classification and regression tree models.

StatMod was then used to run a series of analyses that would have been difficult without such a tool. A …

The Effect Of Lactobacillus Helveticus And Propionibacterium Freudenreichii Ssp. Shermanii Combinations On Propensity For Split Defect In Swiss Cheese, Steven R. White

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

One of the least controlled defects in Swiss cheese is development of splits. Split defect is characterized by fissures or cracks in the body of the cheese that can be as short as 1 cm in length or long enough to span a 90-kg block. This defect appears during refrigerated storage after the cheese is removed from the warm room. Swiss cheese with splits is downgraded because it is unsuitable for use on high-speed slicing equipment (up to 1,000 slices per minute).

A 2x2x2 factorial experiment was used to determine the effect of different commercial Lactobacillus helveticus starters combined with …

Tryptophan Catabolism In Brevibacterium Linens Bl2, Madhavi Ummadi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Recent studies suggest aromatic amino acid catabolism by starter lactococci and flavor adjunct bacteria have a significant impact on off-flavor development during Cheddar cheese ripening. We hypothesized that a flavor adjunct bacterium, Brevibacterium linens BL2, produces off-flavor compounds from aromatic amino acid metabolism that will have a detrimental impact on cheese flavor.

The mechanism of tryptophan (Trp) catabolism in Brevibacterium linens BL2, was investigated in a chemically defined medium during incubation in laboratory conditions (no carbohydrate, pH 6.50, 220 rpm, 25°C) and cheese-like conditions (no carbohydrate, 4% NaCl, static incubation, l5°C). In laboratory conditions, metabolic studies and enzyme assays confirmed …