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Using Immune Modulators To Ameliorate Aleutian Disease In Mink, Kie Hoon Jung May 2003

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 …


The Foraging Behavior Of A Solitary Bee, Diadasia Nigrifrons (Hymenoptera: Anthophoridae) On Sidalcea Oregana, Ssp. Oregana, Kimberly A. Kuta May 2003

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 …


Phylogenetic Position Of Pterocommatinae And Cavariella, And Implications For The Origins Of Host Alternation In Aphids, Carol A. Rowe May 2003

Phylogenetic Position Of Pterocommatinae And Cavariella, And Implications For The Origins Of Host Alternation In Aphids, Carol A. Rowe

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Aphids are morphologically simple. Their numerous hypothesized convergent reductions, such as reduced siphunculi length in association with ant attendance, have made it difficult to define morphological synapomorphies that are necessary for phylogenetic studies. Thus, I used molecular characters both to reexamine the phylogenetic relationships of Cavariella and Pterocommatinae within Aphididae, and to further map host associations and life cycles onto these phylogenies to better understand the evolutionary lability of host alternation within Aphididae. Independent and combined analyses were performed under unweighted parsimony and maximum likelihood criteria for sequences of mitochondrial cytochrome oxidase II plus tRNA-Leucine plus partial cytochrome oxidase I …


Species Pairwise Associations Over Nine Years Of Secondary Succession: Assessing Alternative Explanations And Successional Mechanisms, Lara R. Rozzell May 2003

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 …


Determining The Factors That Control Respiration And Carbon Use Efficiency In Crop Plants, Jonathan M. Frantz May 2003

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 …


Modeling Habitat Quality For American Martens In Western Newfoundland, Canada, William A. Adair May 2003

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, …


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 May 2003

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 …


An Ecological/Life History Comparison Of Two Whitefish Species In Bear Lake, Utah/Idaho, Brett W. Thompson May 2003

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 …


Production Of Volatile Sulfur Compounds From Inorganic Sulfur By Lactococci, Supriyo Ghosh May 2003

Production Of Volatile Sulfur Compounds From Inorganic Sulfur By Lactococci, Supriyo Ghosh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Production of volatile sulfur compounds in cheese is associated with desirable flavors. The direct source of these compounds has been assumed to arise from the metabolism of methionine and cysteine. However, the methionine concentration in cheese rises above the amount found in casein during aging, suggesting that alternative sulfur sources are present in milk. This led us to hypothesize that lactococci may acquire sulfur from the inorganic sulfur pool of milk, in addition to methionine and cysteine, to generate volatile sulfur compounds during cheese ripening.

A turbidimetric method to determine total sulfate content in milk samples was developed. The average …


Factors Affecting Spawning And Survival Of Bear Lake Bonneville Cutthroat Trout In St. Charles Creek, Idaho, Paul Burnett May 2003

Factors Affecting Spawning And Survival Of Bear Lake Bonneville Cutthroat Trout In St. Charles Creek, Idaho, Paul Burnett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I described the spawning ecology of the Bear Lake Bonneville cutthroat trout (BLBCT) in St. Charles Creek. I tracked cutthroat trout with used radio telemetry. I conducted redd counts to describe spawning conditions. Most cutthroat trout in the Big Arm strayed into the Bear River. Cutthroat trout migrations in the Little Arm and main fork were very limited (< 4 km). Redd distributions showed very similar patterns between 1989, 2000 and 2001 with most redds being built in the lowest kilometer of stream. Artificial fish transportation changed the redd distribution in 2002. More redds were built in the main fork and redds were distributed throughout the stream. Redds built in the main fork were characterized by lower levels of fine sediment and higher water velocities as compared to the redds built on the Little Arm. The results of this research will be used to aid resource managers in developing a management plan for wild BLBCT.


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. May 2003

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 …


Catastrophic Wildfire Hazard Assessment In Pinyon-Juniper Woodlands Utilizing A Managerial Paradigm, Benjamin D. Baldwin May 2003

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 …


Rapid Detection Of Listeria Monocytogenes, Wim Lippens May 2003

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 …


The Influence Of Fat And Water On The Melted Cheese Characteristics Of Mozzarella Cheese, Robert Lloyd Fife May 2003

The Influence Of Fat And Water On The Melted Cheese Characteristics Of Mozzarella Cheese, Robert Lloyd Fife

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effect of reducing the fat content of low-moisture part-skim Mozzarella cheese from 19% to less than 5% on melted cheese properties, i.e., apparent viscosity, cheese melt, and cook color, was investigated. Functional properties of melt and stretch and cook color were evaluated at d 1, 7, 14, and 28. A rapid microwave oven method underestimated the moisture content of the low fat cheeses by approximately 10%. Low fat cheese did not melt as well as did the low-moisture part-skim Mozzarella cheese although the moisture content of the low fat cheese (moisture content ranged from 62.5% to 63.6%) was greater …


Rapid Effects Of 25-Hydroxyvitamin D3 On Calcium Uptake In Isolated Chick Enterocytes, Ruta Phadnis May 2003

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 …


Determining The Influence Of The Extracellular Proteinase From Brevibacterium Linens On The Metabolism Of Lactococcus Lactis Spp. Lactis Using Functional Genomics, Yi Xie May 2003

Determining The Influence Of The Extracellular Proteinase From Brevibacterium Linens On The Metabolism Of Lactococcus Lactis Spp. Lactis Using Functional Genomics, Yi Xie

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Since the catabolism of amino acids in cheese results in the formation of most volatile flavor compounds, a proper intracellular pool of amino acids must be established in order to produce a desirable flavor production in cheese. Generation of this pool of amino acids requires complex interactions among casein and its derivatives, proteolytic enzymes, and transport systems in the associated bacteria, including lactococci. In this project, we hypothesized that casein hydrolysis by the extracellular proteinases of Brevibacterium linens BL2 modulates the expression profile of proteolytic related genes in Lactococcus lactis spp. lactis IL1403.

In order to monitor the …


Restoration Of Aspen In Different Stages Of Mortality In Southern Utah, Seth Ray Ohms May 2003

Restoration Of Aspen In Different Stages Of Mortality In Southern Utah, Seth Ray Ohms

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Aspen clones of an aspen-dominated community in Southwestern Utah are declining, some having experienced high mortality coupled with in sufficient regeneration. The objectives of this study were to (I) determine if decadent, non-regenerating mature aspen stands could be regenerated through disturbance of the 111 auxin/cytokinin hormone relationship by clearcutting; (2) determine the extent of ungulate use of regenerating aspen ramets. Clearcuts were made in late summer of 2001 in 10 different clones that exhibited various levels of decline on a continuum from relatively healthy to extremely deteriorated. Nested wildlife/livestock exclosures were constructed in each clearcut plot, as well as in …


Simulation Of Wind Dispersal Of Tree Seeds, Tree Colonization, And Growth Of Bottomland Hardwood Reforestation Sites Of The Mississippi Alluvial Valley, Timothy James Nuttle May 2003

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 …


Physiological And Biochemical Aspects Of Agrobacterium-Wheat (Triticum Aestivum L.) Interactions, David L. Parrott Jr. May 2003

Physiological And Biochemical Aspects Of Agrobacterium-Wheat (Triticum Aestivum L.) Interactions, David L. Parrott Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Agrobacterium tumefaciens and A. rhizogenes are the causal agents of gall or hairy root disease, but normally the bacteria do not cause disease in wheat. However, both bacteria grew without inhibition when exposed to intact or wounded wheat roots or embryos, and they colonized wheat root surfaces to levels similar to dicotyledonous plants. A. tumefaciens and A. rhizogenes induced 23% cell death after a 1-h exposure to wheat embryo cells grown in 7.4 mM O2, while the extent of cell death at 2.1 mM O2 was 8%. Contact with A. tumefaciens or A. rhizogenes caused cultured wheat …


Breeding Bird Communities Of Major Mainland Rivers Of Southeastern Alaska, Jim A. Johnson May 2003

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 …


Influence Of Storage Duration, Temperature, And Oxygen On Quality Of Stored Dehydrated Foods, Omima Ali Darag May 2003

Influence Of Storage Duration, Temperature, And Oxygen On Quality Of Stored Dehydrated Foods, Omima Ali Darag

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was undertaken to determine the effect of oxygen absorber packets (OAP) (AGELESS Z.300 E) in improving the shelf-life of selected dried food products, including dried potato pearls, dried sliced apple, dried carrot, white rice, nonfat dry milk, all purpose flour, rolled oats, and wheat. Items were stored at four different temperatures (-20, 10, 21, and 29.5°C) over a period of 24 months with observations at 6-month intervals. Hunter colorimeter, thiobarbituric acid reactive substance (TBARS) germination rate, gluten weight, and volume were parameters used as quality indicators of various dried foods.

Statistical analysis indicated a significant time and temperature …


Correlation Between The Usu Stretch Test And The Pizza Fork Test, Bryce L. Moyes May 2003

Correlation Between The Usu Stretch Test And The Pizza Fork Test, Bryce L. Moyes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A correlation between the USU stretch test and the pizza fork test would allow the stretch properties of Mozzarella cheese to be measured objectively. The Utah State University (USU) Stretch Test uses a modified texture-profile analyzer to pull strands of cheese from a melted reservoir, measuring the load exerted on the probe during stretching. Parameters measured by the USU stretch test include Melt Strength (FM), which is the maximum load exerted on the probe, Stretch Load (SL), which is the load exerted on the probe at any specified point following FM, and Stretch Extension (SE), which …


Use Of Ground-Based Canopy Reflectance To Determine Radiation Capture, Nitrogen And Water Status, And Final Yield In Wheat, Glen L. Ritchie May 2003

Use Of Ground-Based Canopy Reflectance To Determine Radiation Capture, Nitrogen And Water Status, And Final Yield In Wheat, Glen L. Ritchie

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ground-based spectral imaging devices offer an important supplement to satellite imagery. Hand-held, ground-based sensors allow rapid, inexpensive measurements that are not affected by the earth’s atmosphere. They also provide a basis for high altitude spectral indices.

We quantified the spectral reflectance characteristics of hard red spring wheat (Triticum aestivum cv. Westbred 936) in research plots subjected to either nitrogen or water stress in a two year study. Both types of stress reduced ground cover, which was evaluated by digital photography and compared with ten spectral reflectance indices. On plots with a similar soil background, simple indices such as the …


Effect Of Drought, Flooding, And Potassium Stress On The Quantity And Composition Of Root Exudates In Axenic Culture, Amelia Henry May 2003

Effect Of Drought, Flooding, And Potassium Stress On The Quantity And Composition Of Root Exudates In Axenic Culture, Amelia Henry

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Root exudates include important chelating compounds and can change the rhizosphere pH by several units. These changes are essential for nutrient uptake and can also alter solubility of soil contaminants and increase plant uptake. Mild root-zone stress may increase exudation and more severe stress can damage membranes and increase root turnover, all of which increase root-zone carbon. Increased carbon from this rhizodeposition can increase microbial activity, which might help degrade contaminants. We studied the effect of three types of stress on root exudation of crested wheatgrass (Agropyron cristatum): low K+, drought, and flooding. These stresses were …


The Effects Of Alternative-Site Blood Glucose Monitoring On Testing Frequency, Pain Rating, And Glycosylated Hemoglobin, Nancy Bennion May 2003

The Effects Of Alternative-Site Blood Glucose Monitoring On Testing Frequency, Pain Rating, And Glycosylated Hemoglobin, Nancy Bennion

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A crossover design study was conducted to determine if reducing pain, by using alternative sites off the finger tip, would increase testing frequency and improve clinical outcome as measured by glycosylated hemoglobin. Subjects with type 1 and type 2 diabetes tested with the FreeStyle alternative-site meter (group 1) or tested with their original meter (group 2). After 3 months the subjects used the alternate meter. Testing frequency and blood glucose concentrations were recorded for the month before the study began and monthly thereafter. Glycosylated hemoglobin was tested initially, at the crossover point, and at study conclusion. Insulin users increased testing …