Life Sciences Commons^™

The Feasibility Of Concurrent Enrollment Of High School Students In College-Level Introductory Plant Science, Gregory H. Egan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to test the feasibility of allowing concurrent enrollment in the College of Agriculture to selected high schools in the state of Utah. "Introduction to Agricultural Plant Science" (Plant Science 100) was the course being tested. A purposive sampling technique was used to identify four vocational agriculture programs to participate. There were 86 high school students in the study and 38 college students who took the course on campus at Utah State University.

In this study, 47.7% of the high school students passed the course with a 70% average or above. Comparisons between high school …

The Influence Of Embryo Cell Culture Systems On Pretransfer Development Of Early Ovine Embryos, Pablo Gabriel Daniel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The complete requirements for early embryo development in vitro of the ovine and other domestic species remain unknown. Many studies have concentrated on new media, supplementation, and gas atmosphere formulations.

A newer approach is to coculture early embryos with different cell types to provide the physico-chemical requirements for their development.

In this study, oviduct epithelial (OEC) and dissociated embryo cell (DEC) growth were tested in minimum essential media (MEM) and RPMI. Media were supplemented with fetal calf serum (FCS) and equine derived serum (EDS). Fetal calf serum supported maximum cell confluence in OEC collected on day 3 and day 13 …

Seasonal Variation In The Species Composition, Abundance, And Size-Frequency Distribution Of Zooplankton In Bear Lake, Utah-Idaho, Edmundo G. Moreno

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bear Lake, a large oligotrophic lake (282 km²), was studied from October 1986 to December 1987 to determine the temporal changes in the zooplankton assemblage at one site in the pelagic zone and one in the littoral area. In this study, species composition, abundance, biomass, and size frequency distribution were determined. Additionally, chlorophyll a, water transparency, and temperature and oxygen profiles were measured to help interpret zooplankton changes during the study.

The zooplankton species assemblage comprised eight species of cladocera, seven species of copepods, and five species of rotifers. The abundance and biomass of the zooplankton assemblage, particularly …

Utilization Of Poultry Waste (Composted Caged-Layer) As A Supplement For Sheep Fed Straw During Late Pregnancy, Raul Meneses R.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The utilization of composed caged-layer waste (CCLW) in diets for pregnant ewes fed cereal straw was evaluated. Five sheep were assigned to five diets containing, 0, 5.72, 11.37, 23.80, and 32.69% CCLW in a 5x5 Latin square design. Water intake, feed intake and feces output were measured. Feed and feces were analyzed for dry matter, crude protein, acid detergent fiber (ADF), neutral detergent fiber (NDF), organic matter, hemicellulose and minerals. Thus, nutrient digestibility and nitrogen balance could be calculated. Forty dry, pregnant ewes in the last third of generation were assigned to four dietary treatments contained 0, 11.25, 22.08 and …

Immunologic, Hematologic, And Endocrine Responses To Subacute And Subchronic Exposures To Graded, Subanesthetic Levels Of Nitrous Oxide In Cd-1 Mice, Charles E. Healy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrous oxide (N₂O) oxidizes vitamin B12. disrupting deoxyribonucleic acid (DNA) synthesis. Occupational exposures to subanesthetic levels of the gas have been documented that may result in suppressed proliferative cell activities. Male CD-I mice were exposed to 0, 50, 500, and 5000 parts of N₂O per million parts of air (ppm) for 6 hr/day, 5 days/week for 2 and 13 weeks. Splenic lymphocytes were assayed for responsiveness to mitogens and for the ability to produce interleukin-2 (lL-2) . Tritiated-thymidine ([³H]-TdR) uptake was measured in CD-I splenic lymphocytes cultured in a mixed-lymphocyte culture (MLC). Cytolytic cell …

Some Factors Affecting The Postpartum Interval In Sheep, Jose Pedro Cannas Simoes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effect of genotype on the occurrence of ovulation and estrus during the interval from lambing to ovulation accompanied by estrus (postpartum interval) was measured in White-Face and Black-Face ewes that lambed during the breeding season in 1986 and 1987. A group of St. Croix ewes was added to the study in 1987. The influence of lactation on the events of the postpartum interval was measured by comparing intact and mastectomized White-Face and Black-Face ewes. The effect of prolactin on postpartum interval was measured in these two genotypes and in a group of bromocriptine-treated Black-Face ewes that lambed in 1986. …

Diel Vertical Migration And Feeding Of Underyearling Bear Lake Sculpin Cottus Extensus (Pisces, Cottidae), Darcy Neverman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Underyearling Bear Lake sculpin exhibit a diel pattern of vertical migration throughout the pelagic region of Bear Lake (Utah-Idaho) until they are approximately 22 mm standard length. Individuals move from the bottom of the lake (5° C) during the day into the water column (13-16° C) at night. The migration, however, is not related to feeding. Although the dominant copepod in the water column, Epischura nevadensis, do undergo a similar diel vertical migration, stomach analysis of juvenile sculpin captured by trawling shows that they do not feed in the water column. Instead, from July through October, their diet is dominated …

Chemical Evaluation And Biological Vitamin A Activity Of The Major Carotenoids In The Hybrid Carrot Beta Iii, Cynthia M. Schweitzer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Genetically enhanced high-carotene Beta III hybrid carrot was compared to a commercial carrot cultivar, Nantes Coreless, for carotene content and macronutrient composition. Beta III contained more than twice the total carotene content of Nantes Coreless, with α-carotene/β-carotene ratios higher in Beta III. Total solids from protein, lipids, and carbohydrate were greater in Beta III than in Nantes Coreless. Beta III contained about five times the amount of sucrose and one-fifth the amount of glucose and fructose than Nantes Coreless or reported literature values.

Comparison of the bioavailability of carotenes in Beta III and Nantes Coreless to purified β-carotene and retinyl …

Effects Of Methylene Chloride On Immune Function In Mice And The In Vitro Effect Of Methylene Chloride In Immunologic Assays, Man-Ping Wang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A number of toxicities associated with methylene chloride have been found in both human subjects and mice. However, relatively few studies have probed immunotoxicities of methylene chloride. In order to examine possible immunotoxicities or immunomodulating effects of methylene chloride, several tests of cellular immune function were performed using both human in in vitro studies and a mouse model.

Body weights and specific organ weights of thymus, spleen, liver, and kidney were normal in CD-1 mice given various concentrations of methylenechloride. However, a significantly reduced mitogenic response to phytohemagglutinin (PHA} and reduced interleukin-2 (IL-2} production was found in these methylene-chloride-treated mice. …

Purification And Characterization Of A Chemically Induced Epstein-Barr Virus-Associated Deoxyribonuclease, Guang-Yuh Hwang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Purification of Epstein-Barr virus-associated deoxyribonuclease (EBV-DNase) from Raji and P₃HR-1 cells treated with 12-0-tetradecanoylphorbol-13-acetate and sodium butyrate was performed by sequential ion-exchange column chromatography and fast protein liquid chromatography. The enzyme activity, protein concentration, yield, specific activity, purification profiles, and polypeptide patterns by electrophoretic analysis in each column purification step were determined. The characteristics of the partially isolated EBV-DNase were demonstrated by the enzyme activity, DNA binding affinity, and inhibition by the nasopharyngeal carcinoma patient sera and rabbit polyclonal antibodies against the partially purified EBV-DNase. A nonisotopic assay was developed as a new method in detecting the nuclease. …

Effects Of Exchange Rate Changes On Sugar And Rice Trade Of The Dominican Republic, Gertrudys Brito

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The present research measures the role of exchange rate changes in explaining variations of sugar and rice trade. As background for this research, monetary, fiscal, and exchange rate policies of the Dominican Republic since 1970 are reviewed.

The theoretical framework describing the relationship between exchange rate changes and sugar and rice trade has been tested empirically using the Dominican Republic's annual data for the period of 1970-1987. Regression analyses on the import of rice and export of sugar are estimated.

The regression results conform with the expectation that exchange rate variance is most influential for rice import demand and less …

A Procedure For Developing A Carcass Merit Program For The Pork Industry, James Allen Burrow

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A stratified sample of 420 market hogs representing the seven 10- pound incremental carcass weight classes from 140 lbs. to 210 lbs., and the nine last rib back fat classes from less than .8 inches to 1.5 inches, or greater, within each weight class were analyzed to determine carcass value and yield of wholesale cuts. Simple correlation coefficients were calculated between each of the carcass measurements. The carcass yield data were manipulated by multiple regression procedures to achieve a series of equations for predicting the weights of the primal cuts. The benefits of being able to predict the weights of …

Development Of A Management Plan For Grey Goral: Lessons From Blackbuck And Cheer Pheasant Reintroduction Attempts, Maqsood Anwar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A study of grey goral (Nemorhaedus goral) in the Margalla Hills National Park, Pakistan, was conducted to develop a management plan for this animal. Goral are listed as endangered in Pakistan and elsewhere. They are confined to the steep slopes and difficult terrain that cover 28 percent of the total park area. Another 21 percent of the park area has similar habitat, but currently no goral occur there. Forty to 60 animals are estimated to be living in the park. Groups of two to three animals are common. During observation, goral spent most of their time in feeding, …

Fee Hunting Opportunities On Private Land In Utah: An Economic And Policy Analysis, Lucy A. Jordan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Objectives of this research were (1) to describe fee hunting as it is currently practiced in Utah and (2) to assess the adequacy of fee hunting efforts in addressing the problems of wildlife habitat and hunter access on private land. To collect information, Utah landowners who charged for deer (Odocoileus hemionus) or elk (Cervus elaphus) hunting in 1986 were surveyed by telephone and mail.

Compared to the average Utah livestock rancher, those involved in fee hunting have larger livestock operations and have owned their property longer. They are Utah natives. Fee hunting is concentrated in northern …

Bluetongue Virus Evolution: Sequence Analyses Of The Gene Coding For The Major Serogroup Antigen, Timothy F. Kowalik

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A study was undertaken to better understand the genetic relationship of five United States prototype bluetongue virus serotypes. Genomic double-stranded RNA segment S1, which encodes the major core protein and serogroup antigen, VP7, was used as a marker gene for the sequence analyses. The S1 segments from BTV-2, 11, 13, and 17 were cloned and sequenced by methods developed during the course of this investigation. These results were compared with previously published sequence data from segment S1 of BTV-10. The Sl segments are 1156 base pairs long and contain a common open reading frame capable of coding for a protein …

Impact Of Root Competition On Survival And Growth Of Seedlings Of Important Great Basin Species, Günther Reichenberger

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Belowground competition is pronounced in the arid Great Basin sagebrush ecosystem. Plant demographic and root exclusion approaches were used to examine the influence of roots of adult Artemisia tridentata, Agropyron desertorum, and Agropyron spicatum individuals on seedling survival of Ar. tridentata, Ag. desertorum, Ag. spicatum, and Bromus tectorum. Furthermore, growth rates of Ar. tridentata seedlings and seed production of B. tectorum were assessed.

The probability of a seedling being alive versus dead significantly depended on the seedling species, the neighboring adult species, and on the depth to which root competition was excluded. As seedlings, …

A Study Of Denitrosation Of N-Nitroso Compounds By Irradiation With Long-Wavelength Uv Light, Zhenyu J. Wang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

N-Nitrosamines and N-nitrosamides have been reported to be mutagenic. N-Nitrosamides are direct mutagens that need no activation to be mutagenic, whereas N-nitrosamines need to be enzymatically activated to exert their mutagenicity. Oxidative demethylation of nitrosamines is a commonly accepted activation mechanism. Another pathway of nitroso compounds, denitrosation, has recently been proposed. The mechanism of denitrosation, however, is still unknown.

The purpose of this study was to use a photo -reaction model to explore the possible denitrosation mechanism of N-nitroso compounds. An N-nitrosamine, N-nitrosomorpholi ne (NMOR), and an N-nitrosamide, N-methyl-N'-nitrosoguanidine (MMNG), were irradiated with long-wavelength UV light in the presence of …

Characterization Of Anti-Pichinde Virus Monoclonal Antibodies For The Directed Delivery Of Antiviral Drugs And Toxins, Noah Jefferson Burns Iii

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mouse monoclonal antibodies directed against Pichinde virus (PCV) were produced to evaluate their application as vehicles for the delivery of antiviral drugs or toxins to virus-infected cells. Four monoclonal antibodies, PC4.9A6, PC4.9D3, PC4.7C2, and PC4.8D3, were of the IgG2a subisotype and reacted with acetone-fixed and live PCV-infected Vero-76 cells. In vivo stained splenic macrophages derived from PCV-infected hamsters that had been injected with fluorescein-labeled PC4.9A6 (FITC9A6) demonstrated a 400% increase in total fluorescence over similarly treated, non-infected cells when analyzed by flow cytometry. This is an indication that FITC-9A6 does have some ability to specifically target PCV infected cells in …

Change In Serum Iron As A Measure Of Bioavailability Of Dietary Iron, Mary Beth Wright

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Methods currently used to determine iron bioavailability have disadvantages for both the subjects and researchers involved. One safe and simple method that needs further evaluation, the serum iron absorption method, involves an initial blood drawing, dosages of iron, and blood drawings taken at intervals thereafter. Generally, the rise in serum iron or area under the curve is used to determine iron uptake. Two experiments were conducted using the serum iron absorption method in an effort to improve the utility of this method for the measurement of iron bioavailability. With this effort in mind, an equation adjusting for dose of iron …

Plasmin In Milk: Activity Measurement, Effect Of Environmental Factors, And Correlation With Milk Coagulation, Eric D. Bastian

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bovine plasmin activity was measured on H-D-valyl-L-leucyl-L-lysyl-4-nitroanilide by following absorbance changes at 405 nm. Steady-state kinetic parameters V_max, K_m, K_I, and K_I' were estimated. Bovine plasmin is competitively inhibited by casein and has a K_cat of .0158 ΔA₄₀₅/min/nM, K_m of .107 mM substrate, and K_I of .86 mg/ml casein. Bovine plasmin can be measured directly in bovine milk without interference from casein.

A total of 380 milk samples from nineteen Holstein (one herd) and nineteen Jersey (one herd) cows was collected monthly during one lactation period. Samples …

Influence Of Processing Parameters On Nutrient Recovery During Ultrafiltration Of Milk And Meltability Of Pasteurized Process Cheese Food Made From The Retentate, Susan Kay Fortier Collinge

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Three batches of milk were ultrafiltered to 60, 65, or 70% volume reduction before diafiltration. Starting diafiltration at 70% volume reduction took less time and water without affecting nutrient recovery.

Whole milk was heated to 60, 72, and 82°C for 16 s. Milk representing each heat treatment was divided into three batches, one unacidified (pH 6.6), the others acidified to pH 6.2 and 5.8. The milk was ultrafiltered, diafiltered, and concentrated to 5x (80% volume reduction). Retentate was inoculated with .5% lactic culture and incubated at 28°C to pH 5.1. Each lot of fermented retentate was evaporated under 76 kPa …

Modeling Forest Dynamics Based On Stand Level Resource Allocation, Geoffrey Candler Poole

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An ecologically based model of forest succession is presented. In the model, trees compete for a share of limited growth resources available from their environment. Competition is reflected by each tree's effect on the resource pool and is not explicitly modeled. Model parameters were fit to field data from subalpine forests of the Rocky Mountains. A technique for estimating model parameters from understory-tolerance rankings and silvical characteristics of each species is also presented. The model's output was consistent with our current understanding of forest dynamics. Emergent properties of the model also mimicked natural processes such as self-thinning, release, and maximum …

Using Computer Imaging To Assess Visual Impacts Of Forest Insect And Disease Pests, Daniel Rabin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Forest insect and disease pests alter the appearance of trees, thereby impacting visual resources. Because of the complexity of most forest landscapes, the degree of visual impact of pest-infested forest stands is difficult to quantify.

This paper describes a method of measuring visual impacts of pest-infested forest stands. Photographs of healthy Ponderosa pine trees were entered into a computer video-image-processing system. Using this system, images of trees were altered to simulate different degrees of infestation by limb rust, a forest pathogen.

The altered and unaltered images were shown to groups of observers who rated the scenes in terms of "scenic …

Management, Foraging Behavior, Diet Composition And Forage Quality Of Free-Ranging But Herded Camels In Ceeldheer District, Central Somalia, Ahmed A. Elmi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In Somalia, camel (Camelus dromedarius) survivability and milk production has been higher than for other domestic livestock and contributes substantially to the subsistence of Somali pastoralists. The objective of this research was to study management, foraging behavior and nutrition of camels in their natural habitat to determine how production continues under seasonal nutritional stress.

Management systems of Ceeldheer pastoralists are based on available natural pasture and water. The natural rotation grazing system maintained an ecological equilibrium in the District.

Pastoralists manipulate their herds to suit existing environmental conditions, family needs and labor availability for herding. In herd management, …

Production Of Monoclonal Antibodies Specific For The Gamonts Of Eimeria Tenella, Nancy Carol Larsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Cecal coccidiosis, caused by the protozoan Eimeria tenella, may manifest as a devastating disease in young chickens and result in substantial economic loss for producers. The parasite progresses through a complex life cycle, exhibiting both asexual and sexual (gamont) stages of development. The purpose of this study was to produce a panel of monoclonal antibodies (MoAbs) against epitopes contained on surface antigens (Ags) of the gamonts of E. tenella with the intent of blocking the fertilization process. Gamonts were harvested from infected ceca, partially purified by differential centrifugation throught a discontinuous 5050% Percoll density gradient and used as a …

In Vitro Identification Of The Effect Of Serotonin On Lymphocyte Dna Synthesis And Natural Killer Cell Activity, Kim Kartchener Kane

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to identify the effects of the neurotransmitter, serotonin (SE), on the immune function of peripheral blood mononuclear cells (PBMC) of normal, healthy subjects. This was done as a preliminary investigation to studies on the association of SE with immune changes in autistic subjects.

The PBMC isolated from normal male subjects were treated with various concentrations of SE for 48 hrs. Their incubation in SE at a concentration of 10^-3 M induced about a 35% decrease in DNA synthesis. However, incubation of the cells in lower concentrations (10^-4 to 10^-10) of …

An Apple Rest Model For Mild Winter Conditions, Jose Ignacio Del Real Laborde

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two areas of research are reported: an experiment on the effects of warm temperature prestratification treatments on seed dormancy and a new chill unit model.

Crabapple seeds (Malus sargentii Rehd.) were allowed to imbibe water and were given warm pretreatments at temperatures of 16, 20, 24 and 28C for periods of 3, 10, 20 or 30 days before cold stratification at 4C for 20, 40, 60, 80 or 100 days. Pretreatments resulted in increased chilling requirements for seedling emergence. A short chilling period (20 days) also altered the leaf area, shoot length, internodal length and root/shoot ratio of the …

Phenotypic Characterization Of Actinobacillus And Actinobacillus-Like Species Isolated From Ram Lambs With Epididymitis, Yen-Bou Liu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to characterize phenotypically Actinobacillus and Actinobacillus-like species cultured from ram lambs with epididymitis (lamb epididymitis), so as to better understand the species and strains of Actinobacillus responsible for causing the disease. Two American Type Culture Collection (ATCC) type species of Actinobacillus (A actinomycetemcomitans and A seminis) and 24 field isolates were tested in this study. The field isolates were cultured from either lesions or semen of ram lambs with clinical epididymitis and had been identified as members of the genus Actinobacillus, based on cultural and morphological criteria. When analyzed by …

Root Exploitation Of Fertile Soil Microsites, Robert B. Jackson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Root exploitation of enriched soil microsites was examined for the tussock grasses Agropyron desertorum and Agropyron spicatum and the shrub Artemisia tridentata. Two mechanisms of exploitation of the microsites were examined: root proliferation and changes in nutrient uptake capacity. One day after nutrient solution was applied to small soil patches, the mean relative growth rate of Agropyron desertorum roots in enriched patches was two to four times greater than for roots of the same plants in soil patches treated with distilled water. This rapid and striking root proliferation occurred in response to N-P-K enrichment as well as to P or …

Effect Of Proteolytic Activity Of The Lactic Cultures On Mozzarella Cheese Quality, Wen-Hsu Amos Wang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Mozzarella cheese market is growing rapidly. Major concerns with cheese meltability and color have arisen in the fast food industry. Pre starter culture was used in this study to improve the physical properties of Mozzarella cheese. Three tests (stretch test, melt test, and browning test) were modified to evaluate the quality of cheese.

A stretch test using the Brookfield helipath viscometer to stretch the cheese sample at 60°C was successful in distinguishing cheeses from different make procedures and from different proteolytic strains. A melt test using a glass tube to hold the cheese flow at 110°C for 60 min …