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Isolation And Biochemical Characterization Of Acid- And Bile- Tolerant Strains Of Lactobacillus Acidophilus And Bifidobacterium Bifidum, Lan-Szu Chou May 1997

Isolation And Biochemical Characterization Of Acid- And Bile- Tolerant Strains Of Lactobacillus Acidophilus And Bifidobacterium Bifidum, Lan-Szu Chou

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lactic acid bacteria have been reported to be used as a health adjunct in food for u many years. However, these health benefits have not been proven. and how these bacteria pass through the digestion process and remain viable in the human intestinal tract is still not clear. The aim of this work was to isolate mutants from Lactobacillus acidophilus or Bifidobacterium bifidum that could tolerate the conditions of the digestion process (low pH and bile conduction) and to characterize these isolated mutants.

Acid- and bile-tolerant mutants of L. acidophilus were isolated from parental strains successfully using natural selection techniques. …


Use Of A Self-Administered Food Frequency Questionnaire In A Population 65 Years And Older, Karri Lynn Hoyt May 1997

Use Of A Self-Administered Food Frequency Questionnaire In A Population 65 Years And Older, Karri Lynn Hoyt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Little is known of the elderly's ability to use a food frequency questionnaire to describe their dietary intake. This study examines the elderly's ability to reliably describe their diets and how age, education, cognitive status, and gender may affect their ability to complete and return a food frequency questionnaire. The reproducibility of the questionnaire was tested by a repeated administration among 85 participants 65 years of age and older from the Preston, Idaho, area. Correlation coefficients between nutrient scores from the first and second administration ranged from 0.48-0.79 (total population), 0.44-0.88 (males), and 0.39-0.86 (females). Median values for the correlation …


Relationship Between Taste And Smell Sensitivity To Preference Of A Milk-Based Beverage: Young Versus Elderly Adults, Sally Donahoo Johnson May 1997

Relationship Between Taste And Smell Sensitivity To Preference Of A Milk-Based Beverage: Young Versus Elderly Adults, Sally Donahoo Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

With aging, there is a putative loss of taste and smell that may lead to decreased food enjoyment. We determined the relationships among age, detection, and recognition thresholds for taste and smell, and preference for flavored milk.

Ninety young (20-40 years) and 90 elderly (over 64 years) subjects evaluated chocolate mint-, lemon-, or strawberry-flavored milk. Detection and recognition thresholds were determined for sucrose and for the assigned flavor in milk systems. Sucrose was dissolved in milk, and flavors were dispersed in milk with flavor identification. Preference was determined using a 9-point hedonic scale to evaluate all combinations of five sucrose …


Relative Absorption Of Iron And Magnesium From Sulfate Salts, Amino Acid Chelates Complexed And/Or Mixed With Vegetables, And Taste-Free Supplements, Jennifer A. Bowden May 1997

Relative Absorption Of Iron And Magnesium From Sulfate Salts, Amino Acid Chelates Complexed And/Or Mixed With Vegetables, And Taste-Free Supplements, Jennifer A. Bowden

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Common methods for determining mineral absorption by the body are invasive and frequently utilize radioisotopes. In experiment one. rats were given a dose of radiolabeled ferrous sulfate. Relative absorption was estimated by changes in serum iron and by appearance of the radiotracer in the serum. There were no differences in relative absorption determined by the methods, although the low overall absorptions by the iron-replete rats may have decreased the sensitivity.

In experiments two and three. iron and magnesium supplements were given orally to 12 women age 19-25. Each subject received iron and magnesium supplements once each week for 5 weeks. …


Bark Beetle Activity In Douglas-Fir, Pseudotsuga Menziesii Var. Glauca Mirb. (Franco), Following The 1994 Beaver Mountain Fire, Catherine A. Cunningham May 1997

Bark Beetle Activity In Douglas-Fir, Pseudotsuga Menziesii Var. Glauca Mirb. (Franco), Following The 1994 Beaver Mountain Fire, Catherine A. Cunningham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The 1994 Beaver Mountain fire ignited the canopies of subalpine fir, Abies lasiocarpa, and spread ground fire into adjacent Douglas-fir forests, Pseudotsuga menziesii var. glauca. Despite shorter flight seasons due to lower annual temperatures and persistent snow, the Douglas-fir bark beetle, Dendroctonus pseudotsugae Hopkins, attacked a range of moderately fire-injured host conifers. Logistic regression models illustrated that in 1995 associated bark beetles selected large diameter Douglas-fir with 60-80% bole char, 60-80% crown volume scorch, and 50-70% probability of mortality due to fire. In 1996 beetle preference shifted to smaller diameter trees with lighter fire injury. Tree size was …


A Study Of The Interactions Between Milk Proteins And Soy Proteins, Venkatachalam Narayanaswamy May 1997

A Study Of The Interactions Between Milk Proteins And Soy Proteins, Venkatachalam Narayanaswamy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research investigates the protein interactions that occur when soy protein is added to milk and subjected to renneting or heating. Milk was fortified with 20% soy protein and enzymic coagulation studied at 35°C at various pH's and CaCl2 levels. The first part deals with the interaction between milk and soy proteins during rennet-induced milk coagulation. The first goal was to determine how soy proteins affected milk coagulation. The effects of native versus heat-denatured soy proteins on rennet coagulation time and curd firmness were compared. lmmunogold labeling along with transmission electron microscopy was used to identify and localfze soy …


Evaluation Of Methods Used In Meat Iron Analyses And Iron Content Of Raw, Cooked, And Cured Meats, Eldred Merlyn Clark May 1997

Evaluation Of Methods Used In Meat Iron Analyses And Iron Content Of Raw, Cooked, And Cured Meats, Eldred Merlyn Clark

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research project was divided into three parts. In the first part, heme, nonheme, and total iron methodologies for meats were evaluated. The accuracy, precision, and specificity of each method were determined by spike recoveries of heme and nonheme iron, and by analysis of National Institute of Science and Technology standard reference materials. The most reliable and practical methods were then used to determine the total, nonheme, and heme iron contents of various meats before and after cooking. The meats analyzed were beef, pork, lamb, chicken, and turkey. The wet-ashing technique was a novel procedure in which nitric acid was …


Effect Of Ph, Fat Level, And Various Browning Agents On Composition, Color, Texture, And Sensory Characteristics Of Dark-Cutting Beef Patties, Igor V. Moiseev May 1997

Effect Of Ph, Fat Level, And Various Browning Agents On Composition, Color, Texture, And Sensory Characteristics Of Dark-Cutting Beef Patties, Igor V. Moiseev

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Extra lean (3.3% fat) and lean (20.0% fat) hamburgers in three pH groups (≤ 6.0; 6.01-6.49; 6.50-6.92) were evaluated for cooking-temperature profile, total process lethality, and physical properties after cooking to 71°C by double-side frying on an electric grill. Neither cooking-temperature profile nor cooking time was affected by hamburger fat content or pH. Double-side frying to 71.1°C internal temperature was adequate for more than 6-log destruction of viable E. coli O157:H7 and Salmonella at the geometrical center of extra lean and lean hamburgers. The coldest spot was on the circumferential surface, as indicated by the presence of a red ring …


Physiological Effects Of Chitosan And Chitorichtm On Rats Fed At Two Levels Of Lipid And Fiber, Hyung-Suk Lee May 1997

Physiological Effects Of Chitosan And Chitorichtm On Rats Fed At Two Levels Of Lipid And Fiber, Hyung-Suk Lee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Chitin is a polysaccharide derived from the shell of crustaceans. Chitosan is a deacylated chitin derivative and ChitoRich™ is a chitosan-based formulation. Chitosan is known to inhibit dietary fat absorption. ChitoRich™ and chitosan were evaluated for their ability to control fat absorption in growing rats.

Forty-eight rats (about 150 g) were fed for 4 weeks on 12 different diets containing two levels of vegetable shortening (15 and 5%) and fiber (5 and 2.5%) with cellulose, chitosan, or ChitoRich™ as the dietary fiber sources.

Rats fed ChitoRich™ ate less and gained less body weight than rats fed the other fiber sources. …


Quantitation Of Bovine Serum Albumin In Cow's-Milk-Based Infant Formulas And Removal Of Bovine Serum Albumin From Cow's Milk And Whey Protein Isolates, Patricia Z. Marincic May 1997

Quantitation Of Bovine Serum Albumin In Cow's-Milk-Based Infant Formulas And Removal Of Bovine Serum Albumin From Cow's Milk And Whey Protein Isolates, Patricia Z. Marincic

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Early introduction of cow's-milk-based infant formulas, in particular the ABBOS epitope of bovine serum albumin (BSA), has been implicated as an autoimmune trigger in the pathogenesis of insulin dependent diabetes mellitus (IDDM). A direct enzyme-linked immunosorbant assay (ELISA), using polyclonal anti-BSA antibodies, was developed to determine the BSA content of cow's milk and 15 infant formulas. Powdered high-whey (60%) formulas averaged 41 mg BSA/100 ml; 2% milk contained 52 mg BSA/100 ml; and the high-casein formulas averaged 13 mg/100 ml. BSA content of powdered polymeric formulas and cow's milk varied directly with the whey protein concentration (correlation coefficient = 0.8445, …


Evolutionary Genetics Of Canyon Treefrogs (Hyla Arenicolor), Roy A. Murray May 1997

Evolutionary Genetics Of Canyon Treefrogs (Hyla Arenicolor), Roy A. Murray

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Population genetics is the study of the mechanisms that cause genetic change in populations over time. Genetic changes may lead to both adaptive evolution and speciation. While the former process is fairly well understood, many questions remain unanswered with regard to the process of speciation. How important is population isolation in the process of speciation? How long must populations be isolated before speciation is complete? Are the genetic changes that take place during speciation caused mainly by natural selection or does genetic drift play a substantial role? Can genetic drift alone lead to reproductive isolation? These types of questions have …


The Economic Role Of Range Livestock Production In Kasungu Agricultural Development Division (Kadd), Malawi, Phillip H. W. Phiri May 1997

The Economic Role Of Range Livestock Production In Kasungu Agricultural Development Division (Kadd), Malawi, Phillip H. W. Phiri

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was conducted to determine the effects of season and auction and produce marketing systems on prices received by farmers for livestock sales and the effect of price on cattle numbers sold in KADD. Livestock population, carrying capacity, and stocking rate were estimated. Data were analyzed using pie charts, regression methods, and analysis of variance.

There was no significant difference (P=.06) between cattle prices per kilogram during the wet season and after harvest. During the wet season, significantly more cattle were sold than after harvest (P< .001) to purchase food and farm inputs, and pay school fees and medical bills. Market price was only a secondary factor.

Carrying capacity and stocking rate were estimated at 15.00 kg …


Delineation Of Ecological Units For The Ashley National Forest, At The Landscape Level, Using Classification Tree Modeling, Teresa H. Swiatek May 1997

Delineation Of Ecological Units For The Ashley National Forest, At The Landscape Level, Using Classification Tree Modeling, Teresa H. Swiatek

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study integrated remotely sensed data, geographic information system (GIS), and classification tree-based modeling to delineate ecological units for the Ashley National Forest. Data points, provided by the Ashley National Forest, with a known location and dominant vegetation type, were related to data layers that were determined to be helpful in a landtype classification. These layers included elevation, slope, aspect, potential solar irradiation, precipitation, geology, basins, Landsat thematic mapper (TM) bands 3, 4, 5, and 6, and basic land cover. These points, with their related information, were then used to train the tree-based model for landtype classification. This resulted in …


Wetland Delineation Of Camp Ripley In Minnesota, Richard A. Spencer May 1997

Wetland Delineation Of Camp Ripley In Minnesota, Richard A. Spencer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Department of Defense (DoD) maintains approximately 25 million acres of land that is used for military training in the continental United States. Currently, federal and state laws and regulations require that the DoD land be managed so that any activity, including training, will have a minimal effect on the natural environment.


Development Of Super-Dwarf Wheat Under Stress Conditions Simulating Those On The Space Station Mir, Liming Jiang May 1997

Development Of Super-Dwarf Wheat Under Stress Conditions Simulating Those On The Space Station Mir, Liming Jiang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Super-Dwarf wheat plants were grown in simulation growth chambers under 12 treatments with three photoperiods (18 h, 21 h, 24 h) and four carbon-dioxide levels (360, 1200, 3000, and 7000 μmol/mol). Carbon-dioxide concentrations affected flower initiation rates of Super-Dwarf wheat. The optimum CO2 level for flower initiation and development was 1200 μmol•mol-1. Super-optimum CO2 levels delayed flower initiation, but did not decrease final flower bud number per head. Longer photoperiods not only accelerated flower initiation rates, but also decreased deleterious effects of super-optimum C02. Flower bud size and head length at the same developmental …


A Quantitative Analysis Of Potassium Loss As A Result Of Different Processing Methods, Patricia M. Klefbeck May 1997

A Quantitative Analysis Of Potassium Loss As A Result Of Different Processing Methods, Patricia M. Klefbeck

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Compliance with the strict dietary regimen for the dialysis patient can be very challenging. Many foods are limited from the diet of a renal patient because of the high potassium content. The physiological consequences of failure to follow a diet prescription can be fatal for the dialysis patient. In an effort to improve patient compliance with nutritional protocols, several potato cooking methods and centrifugation of tomato sauce were investigated for their effects in reducing potassium content.

All methods with a 24-hour soak were found to be significant in reducing potassium content of potatoes (P < 0.05). However, some of the methods in which the potatoes were not soaked were also found to be effective in reducing potassium content. Slice thickness and volume of cooking water used were found to be two important factors in determining potassium loss. The 4-mm sliced potatoes, which had a mean potassium value of 84 mg/100 g, lost more potassium than the 8-mm potatoes with a mean potassium value of 182 mg/100 g (P < 0.05). Furthermore, the potatoes cooked in 10 times the amount of water lost more potassium (124 mg/100 g) than those cooked in only 5 times the amount of water (148 mg/100 g) (P < .005). Soaking in cold versus hot water, agitation of the soak water, or the addition of chemical chelators to the soak water were not shown to be any more effective in reducing the potassium content than the other methods. Sensory data indicated that participants did not have a strong taste preference for potatoes cooked by any one particular method (P < 0.05).

Centrifugation of …


Effectiveness Of Grid Systems For Pheromone-Trapping Sparse Gypsy Moth Populations In Mountainous Terrain In The Intermountain West, Colleen Keyes May 1997

Effectiveness Of Grid Systems For Pheromone-Trapping Sparse Gypsy Moth Populations In Mountainous Terrain In The Intermountain West, Colleen Keyes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two field experiments determined an effective intertrap distance (ITD) for early detection and delimitation sparse gypsy moth (Lepidoptera: Lymantriidae, Lymantria dispar L.) populations in mountainous terrain. This study found that current Animal and Plant Health Inspection Service trapping guidelines are not sufficient for early detection of small gypsy moth populations in mountainous terrain. Detection trapping in mountainous terrain should have an ITD of not more than 804 m. Delimiting trapping should use a grid design with an ITD of 152 m.

A related study determined natural adult male mortality in the climate of the intermountain West, which includes Utah, Nevada, …


Evaluation Of Physical And Behavioral Traits Of Llamas (Lama Glama) Associated With Aggressiveness Toward Sheep-Threatening Canids, Sandra M. C. Cavalcanti May 1997

Evaluation Of Physical And Behavioral Traits Of Llamas (Lama Glama) Associated With Aggressiveness Toward Sheep-Threatening Canids, Sandra M. C. Cavalcanti

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Canid predation poses a serious threat to the sheep industry in the United States. Llamas are becoming popular among livestock producers as part of their predation management programs but there is little information on the factors associated with llama guarding behavior. This study examined several physical and behavioral attributes of individual llamas to assess whether they might predict the aggressiveness llamas display coward canids. The study was conducted in three phases. The first involved determining some physical and behavioral traits of individual llamas. Twenty individuals were randomly assigned to one of four groups (n = 5/group) and frequencies with which …


Merits Of Using Tranquilizer Trap Devices On Leg-Hold Traps Used To Capture Gray Wolves (Canis Lupus), Duane P. Sahr May 1997

Merits Of Using Tranquilizer Trap Devices On Leg-Hold Traps Used To Capture Gray Wolves (Canis Lupus), Duane P. Sahr

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Gray wolves (Canis lupus) are frequently captured with leg-hold traps for reintroduction, relocation to reduce depredations on livestock, or as subjects for research projects. Wolves captured with leg-hold traps often sustain injuries to their feet, legs, and teeth during struggles to escape. Other studies have shown that the use of tranquilizer devices on leg-hold traps reduces such injuries to coyotes. This study (1) assessed whether use of tranquilizer trap devices (TTDs) on leg-hold traps reduced the severity of injuries sustained by captured wolves, and (2) examined the effects TTDs have on nontarget species caught during wolf capture operations. Data were …


Identification Of Belowground Woody Structures Using Molecular Biomarkers, Benny R. Bobowski May 1997

Identification Of Belowground Woody Structures Using Molecular Biomarkers, Benny R. Bobowski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Within the last two decades substantial progress has been made in understanding seed bank dynamics and the contribution of the soil seed bank to a post-disturbance plant community. There has been relatively little progress, however, in understanding perennial bud bank dynamics and the contribution of the soil bud bank to secondary succession. This lack of information is due primarily to the inability to reliably identify roots, rhizomes, and lignotubers that lie dormant beneath the soil surface. This scientific investigation, therefore, addressed the issue of identification of belowground woody structures.

The first objective was to develop a methodology that utilizes molecular …


Evaluation Of Translocation Criteria For Trumpeter Swans Reintroduced To Northern Utah: Habitat Quality And Interactions With Tundra Swans, Katharina A. M. Engelhardt May 1997

Evaluation Of Translocation Criteria For Trumpeter Swans Reintroduced To Northern Utah: Habitat Quality And Interactions With Tundra Swans, Katharina A. M. Engelhardt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fifty-seven Trumpeter swans (Cygnus buccinator) were translocated to the Bear River Migratory Bird Refuge and the Bear River Club Company in northern Utah. The purpose of this effort was to encourage dispersal of the Rocky Mountain population of Trumpeter swans during the winter, and to reestablish a migratory route to southern wintering grounds. I assessed the success of the translocation by evaluating 13 translocation criteria proposed in the literature. In this study I addressed two of these criteria in detail by evaluating habitat quality at the translocation sites and by analyzing potential competitive interactions with Tundra swans ( …


The Effects Of Temperature Regime And Food Availability On Growth Rates Of Young-Of-The-Year Colorado Squawfish (Ptychocheilus Lucius) In The Green River, Utah, Craig J. Schaugaard May 1997

The Effects Of Temperature Regime And Food Availability On Growth Rates Of Young-Of-The-Year Colorado Squawfish (Ptychocheilus Lucius) In The Green River, Utah, Craig J. Schaugaard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of different daily temperature regimes and food availability on growth rates of Colorado squawfish (Ptychocheilus lucius) were determined using field and laboratory experiments. Daily temperature and food gradients were observed in river backwaters (important nursery habitat for juvenile Colorado squawfish). High fluctuating temperatures (± 5-8° C) were observed daily in the shallow, terminal ends of backwaters. Where backwaters were in contact with the river (mouth), daily temperature fluctuations decreased (± 2° C). Food availability also varied spatially between the mouth and end of each backwater. To test whether Colorado squawfish growth rates varied in different areas …


Interaction Of The Human Serine Protease Inhibitor Alpha-1-Antitrypsin With Cryptosporidium Parvum, John Russell Forney May 1997

Interaction Of The Human Serine Protease Inhibitor Alpha-1-Antitrypsin With Cryptosporidium Parvum, John Russell Forney

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The human serine protease inhibitor (serpin) alpha-1-antitrypsin (AAT) was studied for potential interaction with components of the protozoan parasite Cryptosporidium parvum. A homogenate prepared from C. parvum oocysts was incubated with purified human AAT, and complexes formed between the serpin and components of the homogenate were detected using an enzyme-linked immunosorbent assay (ELISA). Serpin:parasite infections were effectively blocked by preincubating AAT with a cognate target enzyme, porcine pancreatic elastase, prior to performing the ELISA on the homogenate. Incubation of a mixture of C. parvum oocysts and sporozoites with AAT demonstrated preferential fluorescence labeling of the sporozoite surface membrane by indirect …


Preventive Predation Management: An Evaluation Using Winter Aerial Coyote Hunting In Utah And Idaho, Kimberly Kessler Wagner May 1997

Preventive Predation Management: An Evaluation Using Winter Aerial Coyote Hunting In Utah And Idaho, Kimberly Kessler Wagner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To evaluate preventive aerial coyote hunting as a depredation management technique, I compared sheep losses to coyote (Canis latrans) predation and the hours of corrective predation management required on summer grazing areas with and without hunting the prior winter from helicopters. Correlations were used to test for relationships between the extent, intensity, and timing of aerial hunting and lamb losses to coyote predation. Data on the age, sex, and reproductive status of coyotes killed using aerial hunting on coyote populations.

Winter aerial hunting reduced confirmed and estimated lamb losses to coyote predation and the hours of effort required …


The Role Of Cold Acclimatization On The Biogeography Of The Mountain Chickadee (Parus Gambeli) And The Juniper Titmouse (Parus Ridgwayi), Sheldon J. Cooper May 1997

The Role Of Cold Acclimatization On The Biogeography Of The Mountain Chickadee (Parus Gambeli) And The Juniper Titmouse (Parus Ridgwayi), Sheldon J. Cooper

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Biogeographic patterns of animals are shaped by biotic interactions, such as competition, and by abiotic factors, such as climate. Mountain Chickadees (Parus gambeli) and Juniper Titmice (Parus ridgway) are permanent residents of regions of western North America and are ecologically similar, but have different northern range limits. l measured several physiological variables, including basal metabolic rate (BMR), peak metabolic rate (PMR = maximal thermogenic capacity), metabolic response to varying environmental temperature (MRT), evaporative water loss (EWL), and daily energy expenditure (DEE) for summer-and winter-acclimatized Mountain Chickadees and Juniper Titmice to determine if seasonal and interspecific variation in cold tolerance and …