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All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

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Non-Clinical Risk Factors Of Hysterectomy, Chung-Won Lee May 2001

Non-Clinical Risk Factors Of Hysterectomy, Chung-Won Lee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the United States, hysterectomy is one of the most commonly performed operations for women that is not related with pregnancy. However, not enough attention has been paid to how women's exposure to the surgery differs according to their social characteristics as well attitudinal/behavioral factors. Using cohort data from the National Longitudinal Surveys of Mature Women, this study investigated two aspects: (1) the association between socioeconomic status and hysterectomy and (2) the impact of women's attitudinal/behavioral characteristics on hysterectomy. With Cox proportional hazards analyses, this study found that women's exposure to hysterectomy significantly differs according to their social and attitudinal …


The Relationship Of Milk Urea Nitrogen And Dhia Production Variables In Western Commercial Dairy Herds, Rachael G. Johnson May 2001

The Relationship Of Milk Urea Nitrogen And Dhia Production Variables In Western Commercial Dairy Herds, Rachael G. Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Monthly individual cow DHIA test records (approximately 90,000) from 96 Holstein and Jersey herds from Utah, Idaho, and Montana were analyzed used the Mixed procedure in SAS to determine the relationships of milk production parameters to milk urea N (MUN). Records spanned two consecutive years ending December 2000. Means for Holsteins were 34.1 kg/d milk yield, 15.2 mg/dl MUN, 3.18% milk protein, 3.5% milk fat, and 280,000 somatic cell count. Mean MUN for Holsteins was lowest in fall (Oct.-Dec) and highest in winter and spring. Cows with highest milk protein percent (≥ 3.2%) had lowest MUN over all levels of …


The Effect Of Exopolysaccharide-Producing Cultures On The Moisture Retention And Functional Properties Of Low Fat Mozzarella Cheese, David B. Perry May 2000

The Effect Of Exopolysaccharide-Producing Cultures On The Moisture Retention And Functional Properties Of Low Fat Mozzarella Cheese, David B. Perry

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Low fat Mozzarella cheese was made using exopolysaccharide-producing starter cultures consisting of single strains of Streptococcus thermophilus MR-1C and Lactobacillus delbrueckii ssp. bulgaricus MR-1R with or without the addition of mesophilic exopolysaccharide-producing adjunct mixed culture consisting of Lactococcus lactis ssp. lactis and Lactococcus lactis ssp. cremoris. A control cheese was made using a non-exopolysaccharide-producing starter culture consisting of S. thermophilus TA061 and Lactobacillus helveticus LH100. Cheeses were analyzed for moisture, melt, fat, and protein. Cheeses made with the addition of the mesophilic exopolysaccharide-producing adjunct culture showed significant differences in moisture, but not in melting properties when compared to cheeses …


Affinity Purification Of Bovine Lactoferrin And Bovine Transferrin From Using Immobilized Gangliosides, Seung-Hee Nam May 2000

Affinity Purification Of Bovine Lactoferrin And Bovine Transferrin From Using Immobilized Gangliosides, Seung-Hee Nam

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bovine lactoferrin (BLF) and bovine transferrin (BTF) are major-iron transport and regulation proteins found in bovine whey. BLF and BTF must interact with the eukaryotic cell surface to mediate their biological function of iron delivery and cellular functions of inflammatory and immunological modulation. As common components of the eukaryotic cell surface, gangliosides were used for affinity purification of BLF and BTF.

Bovine gangliosides were isolated from fresh buttermilk and covalently immobilized onto controlled-pore glass beads (66 μg/g beads). After the matrix was loaded with whey protein (WPI or WPC), lactoferrin was eluted with 1 M NaCl and identified by N-terminal …


Influence Of Limited Proteolysis, Heat Treatment, And Ph On The Whiteness Of Skim Milk, Xiaoshan Li May 2000

Influence Of Limited Proteolysis, Heat Treatment, And Ph On The Whiteness Of Skim Milk, Xiaoshan Li

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Health consciousness drives people to drink skim milk. Yet, improving the blue-white appearance and watery texture of skim milk is necessary to make consumers happy with skim milk. In this study, the influence of limited proteolysis with soluble or immobilized proteases, heat treatment, and pH on the whiteness of skim milk were examined to meet this goal.

Limited proteolysis with milk-clotting enzymes increased the whiteness of skim milk. the proteases porcine pepsin and chymosin were immobilized onto nonporous ceramic, glass, and controlled pore glass (CPG) beads. The enzymes were coupled to beads either directly or via crosslinker proteins. Pepsin, immobilized …


Health And Lifestyle Among Ute Native American Elders, Laura L. Prestwich May 2000

Health And Lifestyle Among Ute Native American Elders, Laura L. Prestwich

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A basic health and lifestyle questionnaire was given to a convenience sample of 103 Ute elders, age 50 and older. Fifty-three percent reported being diagnosed with diabetes. The mean BMI (body mass index) was 33.31 (SD=8.72). For descriptive purposes, BMI was divided into three categories: less than 25, 25-29.99, 30 or above. Eleven percent were in the BMI category of less than 25. Thirty percent of Ute elders reported a BMI between 25-29.99. Fifty two percent had a BMI of 30 or above. Diabetes rates among this Ute elder sample were significantly lower with a lower income, lower education level, …


The Effect Of Buttermilk Fraction Concentrates On Growth And Iron Uptake And Transport By Caco-2 Cell Cultures, Yoo-Hyun Lee May 2000

The Effect Of Buttermilk Fraction Concentrates On Growth And Iron Uptake And Transport By Caco-2 Cell Cultures, Yoo-Hyun Lee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To examine the effect of buttermilk fractions on growth, iron transport, and uptake, Caco-2 cells (human colon adenocarcinoma) were grown in a bicameral chamber. The Caco-2 cell culture system is a useful model to study micronutrient utilization in the human enterocyte, because Caco-2 cells continuously differentiate and form a monolayer, which has high polarity, a well-developed brush border, and a tight junction.

Iron bioavailabilty in various milks is very different depending upon milk composition. The fat fraction especially is known to be associated with iron absorption, because the fat fraction has milk fat globule membrane (MFGM), which contains bioactive molecules …


Effects Of Ph And Calcium Level On Extrusion-Textured Whey Protein Products, Andrea B. Hale May 2000

Effects Of Ph And Calcium Level On Extrusion-Textured Whey Protein Products, Andrea B. Hale

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of altering pH and calcium level during whey protein extrusion were assessed by measuring the protein solubility and WHC of the textured whey protein (TWP). TWP samples were produced by extruding dry mixtures of 2/3 WPC 80 (80% protein) and 1/3 cornstarch using screw speed of 200 rpms, feed rate of 23 g/min, water flow rate of 11 g/min, and product temperature of 150°C. The levels of acid and base were adjusted by adding concentrated HCl or NaOH, respectively, to the water source. Calcium was added to the raw mix in the form of calcium chloride dihydrate before …


Returns To Public Agricultural Expenditure Under Uncertainty, Sanjeev Misra May 2000

Returns To Public Agricultural Expenditure Under Uncertainty, Sanjeev Misra

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A vast literature has investigated the returns to investment in agriculture research and generally found extremely high rates of return. These results suggest policymakers would do well to maintain or increase resource allocation to public agricultural research. Remarkably little attention has been paid, however, to the issue of how best to allocate public agricultural research funding between competing research areas and organizations. This paper considers the relative returns to alternative uses of public agricultural research funds committed to the agricultural experiment stations of 10 western states of the United States over the years 1967-91. A model of expected utility maximization …


An Investigation Of The Cone And Seed Insects Of Whitebark Pine And Alpine Larch Emphasizing The Western Conifer Seed Bug (Hemiptera: Coreidae) And The Larch Cone Fly (Diptera: Anthomyiidae), Laurel K. Anderton May 2000

An Investigation Of The Cone And Seed Insects Of Whitebark Pine And Alpine Larch Emphasizing The Western Conifer Seed Bug (Hemiptera: Coreidae) And The Larch Cone Fly (Diptera: Anthomyiidae), Laurel K. Anderton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Laboratory and field feeding tests with Leptoglossus occidentalis Heidemann proved that both immature and mature seed bugs can use cones and foliage of whitebark pine, Pinus albicaulis Engelmann, as a food source for 1- to 2-week periods. Damage to unprotected whitebark pine cones by seed bugs ranged from 0.3 to 2.1 % of seeds per cone, and for bagged cones averaged 0.7% of seeds per cone. Total insect damage ranged from 0.4 to 7.2% of seeds per cone. A seed chalcid, Megastigmus sp., was documented for the first time on whitebark pine and damaged 4.7% of examined seeds at one …


Prevalence And Possible Causes Of Vitamin B-6 Deficiency Among Women In The Philippines, Siew Sun Wong May 1999

Prevalence And Possible Causes Of Vitamin B-6 Deficiency Among Women In The Philippines, Siew Sun Wong

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Recently maternal intake of multivitamins has been associated with a reduced risk of orofacial clefts (OFC) in human epidemiologic studies. In the Philippines, vitamin B-6 deficiency was found to be associated with increased risk of OFCs. The birth prevalence of OFCs in the Philippines is among the highest known, but Filipino emigrants in the United States have lower rates, indicating that environmental factors may play an important role in causing OFCs in the Philippines.

The prevalence and possible causes of vitamin B-6 deficiency were investigated through dietary and biochemical assessments in case-control study in Negros Occidental, Philippines. Mothers with OFC …


The Relationships Among Body Satisfaction, Self-Esteem, And Social Support In Undergraduate Men And Women, Sarah Murray Hodson May 1999

The Relationships Among Body Satisfaction, Self-Esteem, And Social Support In Undergraduate Men And Women, Sarah Murray Hodson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Significant levels of body dissatisfaction exist among college women. Research has also shown levels of body dissatisfaction among college men. Numerous studies have been conducted to investigate the relationship between body dissatisfaction and self-esteem as well as the relationship between self-esteem and social support. Past research, however, has neglected to determine if a relationship exists between body dissatisfaction and social support.

This study sought to determine if this relationship exists for college men and women. The present study was also developed to test the relationships that have been found between social support and self-esteem as well as between self-esteem and …


Growth Of Clostridium Sporogenes Pa3679 In A Vacuum-Packaged Meat-Vegetable Product, Julie M. Racz May 1999

Growth Of Clostridium Sporogenes Pa3679 In A Vacuum-Packaged Meat-Vegetable Product, Julie M. Racz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Clostridium sporogenes PA 3679 spores were inoculated into a meat-vegetable mixture before extrusion, cooking, and vacuum packaging into "stewsticks" to simulate Clostridium botulinum growth. The experiment was a 3 x 5 x 2 x 3 factorial which determined the influence of pH, water activity, initial spore load, and storage period on spore survival. Spore levels decreased throughout storage for all treatments. Spore levels decreased linearly (P = 0.02) as water activity increased, in samples that were heated to kill vegetative cells and activate spores. Other significant interactions of heat-treated samples were observed with inoculum level (P < 0.01) and storage time (P < 0.01). Spore levels in stored products were also significantly affected by water activity * inoculum level (P = 0.03), pH * time, water activity * time (P = 0.01), inoculum level * time (P < 0.01), and water activity * inoculum levels * time (P < 0.01). The interaction between pH * water activity * time tended towards significance (P = 0.06). Most probable number estimates in nonheated samples accounted for naturally occurring viable cells and spores, and added spores and were significantly affected by the main effects of inoculum level (P < 0.01) and time (P < 0.01). The two-way interactions of water activity * inoculum level (P = 0.04), pH * inoculum level (P < 0.01), water activity * time (P < 0.01), and three-way interaction of pH * inoculum level * time (P = 0.03) were significant. Spore levels approached 102, or less …


Influence Of Carbohydrate Starvation On The Culturability And Amino Acid Utilization Of Lactococcus Lactis, Mark R. Stuart May 1999

Influence Of Carbohydrate Starvation On The Culturability And Amino Acid Utilization Of Lactococcus Lactis, Mark R. Stuart

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lactococci are widely used in the cheese industry as a starter culture. Starter cultures face carbohydrate starvation due to the absence of a fermentable carbohydrate in the cheese curd after pressing. Starvation leads to a decreased ability to synthesize ATP, generate a proton motive force, and accumulate nutrients necessary to maintain viability. The aim of this work was to investigate the culturability of lactococci grown with and without lactose in a chemically defined medium, and to define the metabolic changes that occur during carbohydrate starvation.

Lactose metabolism provided energy for logarithmic phase growth and greater cell density in L. lactis …


Influence Of Commercial Starter Media On Biochemical Characteristics Of Lactococcus Lactus, Norman Bart Devries May 1999

Influence Of Commercial Starter Media On Biochemical Characteristics Of Lactococcus Lactus, Norman Bart Devries

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Five strains of Lactococcus lactis were inoculated individually into six commercial bulk set growth media, 11% non-fat dry milk (NDM), and Elliker's broth. After growth in each medium the strains were tested for rate of acid production, and activities of proteinase, aminopeptidase, and lipase/esterase. Growth in commercial starter media significantly influenced acid production rate (P = 0.040), aminopeptidase activity (P < 0.0001), and lipase/esterase activity (P < 0.0001) .

For selected strain/media combinations, the duration of induced aminopeptidase and lipase/esterase activity was followed. The chosen strains were grown in selected commercial bulk set media, reinoculated into 11% NDM, and enzyme activity was examined for five successive …


In Vitro Growth Of Muscle Satellite Cells Isolated From Normal And Callipyge Lambs, Beatriz T. Rodriguez May 1999

In Vitro Growth Of Muscle Satellite Cells Isolated From Normal And Callipyge Lambs, Beatriz T. Rodriguez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The muscle hypertrophy of lambs expressing the Callipyge phenotype is possibly linked to characteristics of their muscle satellite cells. Therefore, characteristics (proliferation, fusion %, and protein accretion) of cultured satellite cells isolated from the longissimus muscle of Callipyge (n = 3) and normal (n = 3) lambs were compared in this study. In the first experiment, we tested whether or not the lll proliferation rates differ for satellite cells isolated from Callipyge or normal sheep when cultured in the presence of different serum types (horse, normal lamb, or Callipyge lamb). The average population doubling time (PDT, h) during log phase …


Studies On The Utilization Of Deboned Trout (Oncorhynchus Mykiss) Frames In Fish Snack, S. Muralidharan May 1999

Studies On The Utilization Of Deboned Trout (Oncorhynchus Mykiss) Frames In Fish Snack, S. Muralidharan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Snack food development studies were conducted to iii utilize trout (Oncorhynchus mykiss) frames, a by-product of the filleting operation, using extrusion and conventional technology. Twin screw extrusion studies were conducted to study the effect of fish mince, non-fat dry milk, process temperature, and moisture content on the physicochemical properties of the extruded snack food. Response surfaces were plotted to understand the effects of the independent variables on dependent variables such as bulk density, expansion ratio, shear strength, and water absorption index. Quadratic models expressed the relationship between the dependent and independent variables.

Based on the extrusion studies, conditions …


The Development Of Pediococcus Species As Starters For Mozzarella Cheese, Shelby L. Caldwell May 1999

The Development Of Pediococcus Species As Starters For Mozzarella Cheese, Shelby L. Caldwell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bacteriophage infection of Streptococcus thermophilus is a growing concern in the mozzarella cheese industry. One method to control this problem may be to replace S. thermophilus with a starter coccus from a different genus of lactic acid bacteria. This work evaluated the possibility of using genetically modified Pediococcus spp. for this approach. Electroporation was used to introduce genes for lactose utilization from Lactococcus lactis into strains of P. acidilactici and P. pentosaceus. The resulting lactose-positive transformants, P. acidilactici SAL and P. pentosaceus SPL-2, rapidly reduced the pH of lactose broth, accumulated [14C]lactose at a rate higher than …


Methanethiol And Cheddar Cheese Flavor, Benjamin Dias May 1999

Methanethiol And Cheddar Cheese Flavor, Benjamin Dias

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The use of slower acid-producing starter bacteria for the production of lower fat Cheddar cheese has lead to milder flavor Cheddar cheeses that lack intense Cheddar notes. The metabolism of methionine leads to the production of methanethiol, which is one of the desirable Cheddar cheese flavor compounds. The influence of NaCl and reduced pH was determined for aminopeptidase, lipase/esterase, and methanethiol-producing capability in selected lactic acid bacteria and brevibacteria in simulated cheese-like conditions. The activity of each enzyme decreased with NaCl addition and pH reduction to approximate a Cheddar cheese environment (5% NaCl and pH 5.2).

The mechanism for methanethiol …


Heat-Induced Gelation Of Ultrafiltered Whole Milk Concentrate And Product Applications, Hector Alejandro Solorio May 1999

Heat-Induced Gelation Of Ultrafiltered Whole Milk Concentrate And Product Applications, Hector Alejandro Solorio

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The heat-induced gelation properties of ultrafiltered (UF) whole milk concentrate were studied under different physical and chemical conditions. total solids concentration, homogenization pressures, heating temperatures, and heating times were found to have a positive correlation with gel strength. The addition of calcium chloride, sodium chloride, or trisodium citrate produced gels of higher strengths and textural properties than the gels obtained with non-salt-treated concentrate. Calcium chloride produced the strongest gels with a cheese-like texture and poor spreadability. Sodium chloride produced gels of intermediate strength with a firm, elastic texture and poor spreadability. Trisodium citrate produced the softest gels with a smooth, …


A Study Of The Effects Of Proteolytic Adjunct Culture On The Physical And Functional Properties Of Low-Fat Mozzarella Cheese, Roxanne Stone May 1999

A Study Of The Effects Of Proteolytic Adjunct Culture On The Physical And Functional Properties Of Low-Fat Mozzarella Cheese, Roxanne Stone

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As fat is removed from Mozzarella cheese, the resulting increase in protein content causes the cheese to become tough, thus decreasing the desired physical characteristics of meltability and stretch. Low-fat (6% fat) Mozzarella cheese was manufactured with the addition of several levels of a Lactococcus lactis adjunct culture that was proteinase positive and lactose deficient in an attempt to improve these physical properties. During cheese manufacture, milk was acidified to pH 6.0, then inoculated with Lactobacillus helveticus and Streptococcus thermophilus. Experimental vats were also inoculated with either 0.25, 0.50, or 1.0% of the adjunct culture. Cheeses made with the …


Heat-Stable Extracellular Enzymes Of Pseudomonas, Ramarathna Koka May 1999

Heat-Stable Extracellular Enzymes Of Pseudomonas, Ramarathna Koka

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Psychotrophic bacteria produce heat-stable lipase, protease, and phospholipase. Pervious studies indicate the production of multiple enzymes in several strains of Pseudomonas fluorescens, but conclusive evidence is lacking.

The influence of culture conditions on the production and thermostability of phospholipase, protease, and lipase was investigated in 17 raw milk and environmental isolates. Production and thermostability of the enzymes were influenced by strain, stage of growth, and the culture medium. Cross-reactivity of antibodies raised to a purified protease and a commercial lipase indicated the immunological diversity of the enzymes.

Protease purification was undertaken to investigate the production of multiple proteases within a …


A Product Development Study: Rainbow Trout Bologna, Marshall Dean Smith May 1999

A Product Development Study: Rainbow Trout Bologna, Marshall Dean Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mechanically deboned rainbow trout (Oncorhynchus mykiss) was analyzed and then used in texture studies. The meat contained a moderately low amount of fat (10% ± 2%, x ± SD). Pre-deboned meat had more calcium than deboned meat (P < 0.001). Sausages were made of fish and various non-meat ingredients including egg whites, collagen, soy protein isolate, starch, cellulose, and wheat gluten. Adhesiveness, cohesiveness, hardness, shear and springiness of the cooked sausages were measured to describe texture. The data were fit to linear and quadratic models. Adhesiveness data did not fit the model (F(6,50)=1.1, P > {F{=0.37). A combined response model predicted formulations for fish sausage that would closely duplicate the texture of commercially available processed meats. A thermal model was developed that helped verify the thermal properties of rainbow trout. Thermal conductivity was measured (k == 0.48 W/m·K) and specific heat was calculated (Cp= 3200 J/kg·K).


Fathers And Sons: An Examination Of Distancing Patterns During Adolescence, Mark Ogletree May 1999

Fathers And Sons: An Examination Of Distancing Patterns During Adolescence, Mark Ogletree

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Although there has been a new wave of research on fathering, little has focused specifically on the father and son relationship during adolescence. Previous research has documented that fathers and their daughters tend to distance themselves and disengage at the onset of menarche; however, the study and analysis of what happens to fathers and sons during the onset of puberty has been practically neglected. Several studies through the mid 80s and early 90s documented that parents and children tend to separate during adolescence, but only scant research has been conducted since that time. The goal of this study was to …


Influence Of Type Of Supplemental Carbohydrate On Ruminal Responses And Methane Output From Ruminants Consuming Low-Quality Forage, Raul J. Lira May 1999

Influence Of Type Of Supplemental Carbohydrate On Ruminal Responses And Methane Output From Ruminants Consuming Low-Quality Forage, Raul J. Lira

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In a completely randomized design with a factorial arrangement, three energy supplements and two species (cows and ewes) were evaluated in two identical experimental periods: gestation and lactation. The three supplement treatments were a control, barley, and sugar beet pulp (SBP). The basal diet was tall wheatgrass straw (5.52% CP).

Forage and total dry matter intake (FDMI and TDMI, respectively) interacted (P=.04) with species, supplements, and physiological stages.

An interaction of physiological stage and sampling time occurred for pH. Supplement and sampling time interacted for butyric acid proportion and total VFA concentration.

Diet digestibility displayed an interaction between …


The Impact Of The Ideal Thin Body Image On Women, Nicole Hawkins May 1999

The Impact Of The Ideal Thin Body Image On Women, Nicole Hawkins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Researchers and clinicians have postulated that the thin-ideal image portrayed in the media leads to body dissatisfaction and negative self-appraisals among women; however, there is little research that has directly examined the effects of these images on women. The purpose of this research investigation was to experimentally examine the effects of exposure to the thin-ideal on women's affect, self-esteem, body satisfaction, and level of internalization of the thin body image. This study also assessed how the thin-ideal image differentially impacted women with a diagnosed eating disorder. College women (N = 145) were randomly exposed to photographs from popular magazines …


Navajo Adolescent Pregnancy: Identifying Ecocultural Factors Among Adolescent Mothers And Their Infants, Jessiline Anderson May 1999

Navajo Adolescent Pregnancy: Identifying Ecocultural Factors Among Adolescent Mothers And Their Infants, Jessiline Anderson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding the adaptational responses and ecocultural niche of the Navajo adolescent mother from her perspective provides a richness of information about a little-studied population. The overall purpose of this study was to explore the ecocultural factors determined to be significant in the decision of a Navajo adolescent mother to remain in high school or drop out of high school. Thirty Navajo adolescent mothers recruited from two small reservation towns in eastern Arizona participated in the study. Navajo adolescent mothers in the study participated in a one and one half hour semistructured accommodations interview, and completed a Family Resource Scale and …


Effects Of Perceived Sugar Or Chocolate Intake On Self-Reported Food Cravings, Mood States, And Food Intake: A Double-Blind, Placebo-Controlled Study, Lara J. Schultz May 1999

Effects Of Perceived Sugar Or Chocolate Intake On Self-Reported Food Cravings, Mood States, And Food Intake: A Double-Blind, Placebo-Controlled Study, Lara J. Schultz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Many dieters and compulsive overeaters report that sugar and chocolate are the most commonly craved foods. Further, many individuals have proclaimed themselves to be "addicted" to sugar or chocolate. It remains unclear, however, what factors lead to report of specific food addictions. A number of researchers have suggested that highly repetitive consumption of sugar and chocolate may result from various physiological processes (e.g., neurochemical imbalances, glucose/insulin malfunctioning). However, there is also considerable evidence that psychosocial factors (i.e., expectancies, classical, and operant conditioning) play the major role in the development and maintenance of excessive sugar/chocolate intake. Empirical studies examining factors that …


Nest Success Of Dabbling Ducks In A Human-Modified Prairie: Effects Of Predation And Habitat Variables At Different Spatial Scales, Jaime E. Jimenez May 1999

Nest Success Of Dabbling Ducks In A Human-Modified Prairie: Effects Of Predation And Habitat Variables At Different Spatial Scales, Jaime E. Jimenez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nest success of dabbling ducks in the Prairie Pothole region of North America has been declining for the past 40 years in parallel with declines in duck populations. Low nest success seems to result from the combination of an extremely fragmented breeding ground in a human-dominated landscape with an abundant and expanding community of generalist nest predators. Studies that examined variables associated with nest vulnerability to predation have produced contradictory results, likely because of simplistic approaches, lack of spatio-temporal replication, use of artificial nests, and the effect of confounding variables. I attempted to clarify the equivocal findings of previous studies …


Influence Of Grazing, Fire, And Rainfall Regime On Plant Species Dynamics In An Ethiopian Perennial Grassland, Michael J. Jacobs May 1999

Influence Of Grazing, Fire, And Rainfall Regime On Plant Species Dynamics In An Ethiopian Perennial Grassland, Michael J. Jacobs

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The dominant habitat-type of Omo National Park (ONP), Ethiopia, is grassland. This grassland supports a variety of wild herbivores and indigenous people; the latter hunt large herbivores for subsistence or graze their domestic livestock in the Park. Therefore, an understanding of grassland dynamics is a high priority for ONP management. Grazing and fire are major factors influencing species composition and vegetation change in East African grasslands. Rainfall regime, in turn, can influence both grassland response to grazing and fire. The ONP grasslands occur along a rainfall gradient ranging from subhumid to semiarid. Research objectives were to: (1) test the Milchunas, …