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Factors Affecting Seeds In A Sagebrush-Steppe Ecosystem And Implications For The Dispersion Of An Annual Plant Species, Cheatgrass (Bromus Tectorum L.), Michael Ira Kelrick

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I investigated how shrub-induced spatial heterogeneity influenced and was manifested by a representative ground-story plant species at a sagebrush-steppe site in southwestern Wyoming. The dispersion of cheatgrass (Bromus tectorum) reflected differences between undershrub (higher plant densities) and interspace (between shrubs, supporting lower densities) microenvironments, hence the population ecology of this annual species served as a biological probe of shrub-associated patch structure in this community. Since cheatgrass is an annual, factors affecting the seed portion of its life cycle were of special interest. First, attributes of the above- and below-ground seed pool were characterized. The environment-wide seed depositional pattern …

Reproductive Strategies Of Northern Goshawks And Cooper's Hawks In North-Central New Mexico, Patricia L. Kennedy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I assumed that the reproductive strategies of the two Accipiter species investigated in this study, the northern Goshawk (A. gentilis) and the Cooper's hawk (A. cooperii), would be similar to the strategies of other monogamous raptors with sex role partitioning. Any differences in the species' reproductive strategies, particularly hunting strategies, were expected to be a function of their size differences. Contrary to predictions, results indicated that, in north-central New Mexico during brood rearing, both species had similar hunting strategies and utilized similar prey species. These results also indicated that the reproductive strategies of the Cooper's hawk …

The Play Of Visually Impaired Preschoolers With Their Mothers, Claudia Weber

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis answers the following questions: (a) Is the Play Assessment Scale a true measure of development? (b) Does the mother have a significant, positive influence on the child's level of development? (c) Does the mother's interactional style influence the child's development as measured by the Play Assessment Scale and the Battelle Developmental Inventory? The subjects were 13 visually impaired preschoolers. Development was measured with the Play Assessment Scale and the Battelle Developmental Inventory. Maternal interactional style was assessed with the Parent/Caregiver Involvement Scale. The study indicated that the Play Assessment Scale is a valid, reliable measure of development in …

Creating Ethnicity In The Hydraulic Village Of The Mormon West, Charles M. Hatch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study has looked behind the mask of nineteenth-century theocracy to see Mormons in the Great Basin creating a democratic society of regionally concentrated kin groups where obligations and rewards for individuals were increasingly determined by age and life cycle position. As generations of young adults acted together in self-interest dispersing their villages on receding frontiers, they forged a balance between competition and cooperation which merged the immediate need of individuals to establish and support families with the collective memory of their Mormon past. In so doing, they created an identity for themselves which was unique in the arid West. …

Economic Strategies For White-Tailed Deer And Livestock Production On Central And South Texas Ranches, Will E. Cohen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Recently, hunting and associated recreation have become an important business for Texas landowners. Most ranchers want to realize maximum net return from their investments. This study's objectives were to develop white-tailed deer (Odocoileus virginianus) and livestock enterprise budgets and to determine optimal economic combinations and levels of deer and livestock enterprises to maximize net returns. Questionnaires were mailed to landowners in the Edwards Plateau and South Texas Plains who purchased shooting preserve licenses in 1985. Five hundred and twenty-four ranchers responded (23.4%). Respondents were segregated by enterprises (deer, cattle, sheep, and Angora and Spanish goats) and a 5% …

Development And Evaluation Of An Expert System For Use As An Aid In Culling Dairy Cattle, Max L. Checketts

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An expert system for identifying cows to be culled, MAXCULL, was programmed to run on an IBM or compatible personal computer. It was designed to be used with Dairy Herd Improvement (DHI) records as an aid in decision making. MAXCULL used fifty-two health, seventeen reproduction, and thirty-nine production rules in the analysis.

MAXCULL was initially developed using two expert system tools. VP-Expert and Super Expert both had inductive abilities and were reasonably priced. VP-Expert was selected to continue the development of the MAXCULL system. The program used a rule-based method of storing knowledge, which was obtained from literature reviewed in …

Identification Of Potential Adhesins Shared Among Isolates Of Actinobacillus Species And Actinobacillus-Like Bacteria Cultured From Ram Lambs With Clinical Epididymitis, Yu-Wen Liu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ram lamb epididymitis, a serious reproductive disease of sheep, is caused principally by bacteria belonging to the genera Haemophilus and Actinobacillus. Six bacteria were studied: the American Type Culture Collection (ATCC) of Actinobacillus seminis (ATCC 15768), ATCC of Actinobacillus actinomycetemcomitans (ATCC 29522), field isolates of A seminis (86722 and 4101) and field isolates of Actin obacillus- like bacteria (Y136 and D107). The objectives of this study were to quantitate the adhesion of these 6 bacteria to bovine kidney epithelial cells (BKECs) and ram epididymal epithelial cells (REECs), evaluate the effect of rabbit polyclonal antibody prepared against ATCC 15768 …

Evaluation Of Antiviral Compounds Against Avian Influenza, Evan W. Call

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tests in vitro for antiviral activity against avian influenza viruses, A/Turkey/Sanpete/85 (H6N8) and A/Turkey/Sanpete/86 (H10N9), isolated in Sanpete County, Utah, utilized known antiviral agents, amantadine⋅HCl (adamantanamine hydrochloride) and ribavirin (1-β-D ribofuranosyl-1,2,4-triazole-3-carboxamide). The testing involved evaluation of seven drug concentrations. Maximum tolerated dose, minimum inhibitory concentration and therapeutic indexes were determined for each drug used. Both drugs demonstrated reasonable antiviral activity. Then they were tested against the H10N9 strain in 10-day-old Broad White turkey poults. Large- and small-particle aerosol delivery systems were the delivery methods utilized. Various parameters, including water and feed consumption, health score (based on visible signs), recoverable lung …

Ethical Beliefs And Practices: Do Psychologists Differ From Other Health-Care Professionals, Gary Percival

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ethical codes and principles, and laws govern the behavior of health-care professionals. Yet, the impact that ethical codes and laws have on the actual moral behaviors of health-care professionals is relatively unknown. A survey on the ethical beliefs and practices of health-care professionals was sent to the United States membership of the Association for Applied Psychophysiology and Biofeedback. AAPB's heterogeneous membership offers a unique opportunity to compare the ethical beliefs and behaviors of professionals across various health-care professions, educational levels, licensure and certification statuses, age, years in practice, and gender. The survey examined the respondents' ethical beliefs and practices in …

Meat Effects On Nonheme Iron Absorption, Yunji Kim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Studies were undertaken to investigate if gastric acidity and iron chelation to a meat component enhance nonheme iron absorption. Cereal meals, with and without added proteins, were gavaged into iron-deficient rats. The role of iron chelation was investigated by adding sodium phytate, an iron chelator implicated with decreased iron absorption, to the meals. The role of gastric acidity was investigated by treating the rats with cimetidine, which inhibits gastric acid production. In rats with normal acid production, beef, pork and chicken enhanced iron absorption when phytate had been added to the meals, suggesting a role for chelation in meat enhancement …

Determining The Validity Of Methods Used In Meat Iron Analysis, Padmashri Ummadi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The validity of the Homsey method for heme iron, modified Schricker and sodium pyrophosphate extraction methods for nonheme iron and atomic absorption spectrophotometry (AAS) and ferrozine methods for total iron were determined using spikes of hemoglobin, ground beef baked to different degrees of doneness, proportional beef liver:catfish mixtures and National Institute of Science and Technology reference materials.

The mean spike recoveries of 0.01g and 0.02g Hb in raw beef and raw chicken samples were 96.7% of the heme iron for the Homsey method, 97.9% of the total iron for the ferrozine method, and 85.7% of the total iron for the …

Changes In The Vulvular And Vestibular Tissue Of The Bovine During The Estrous Cycle As Determined By The Use Of Near Infrared Interactance, Robert Alan Kunzler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Near infrared reflectance spectroscopy is routinely used for the analysis of quality components of feedstuffs. Near infrared spectrophotometers, coupled with a fiber optic probe, could enable direct measurements of the live animal. This study was conducted to characterize changes in the vulva and vestibule during the bovine estrous cycle using near infrared (NI) spectroscopy. Sixteen cycling Holstein cows were observed for estrus twice daily from 40 days postpartum for three estrous cycles or until conception was verified. In addition, weekly rectal palpations, cowside milk progesterone tests, and tailhead chalk were used to aid in estrous detection. Near infrared spectra of …

Potassium And Sodium Interrelations In Alfalfa Phenotypes Grown On Calcareous Soil, Suresh S. Dhumal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Three greenhouse experiments were conducted with three phenotypes of alfalfa (Medicago sativa L.) obtained from a potassium (K)-deficient field and with their diallel crosses grown on low K soil. The first experiment was conducted to study the partitioning and broad-sense heritability of K and sodium (Na) between leaves and stems of the three phenotypes which were deficient in K and exhibited normal (N), marginal chlorotic (M), and white spot chlorotic (W) leaflets. The second experiment was conducted to study the partitioning of K and Na in leaves, stems, and roots as influenced by 32 alfalfa crosses obtained from diallel …

Hydrogen Uptake Genes And Nitrogen Fixation Efficiency Of Rhizobium Species In Symbiosis With Alfalfa, Chickpea And Pigeonpea, G. Mustafa Sajid

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The plasmids pDN211 and pDNll, isolated from the gene bank of the Rhizobium japonicum strain I-110, have been reported to complement two different Nif⁺ Hup^· (nitrogen fixation positive and hydrogen uptake negative) mutants. A 5.9-kb Hindiii DNA fragment of the cosmid pHU52, isolated from the gene bank of R. japonicum strain 122DES, has been reported to code for the two polypeptide subunits of uptake hydrogenase. To determine homology between the structural genes of uptake hydrogenase of the two strains, a Southern blot of the Hindiii restriction fragments of the plasmids pDN211 and pDN11 was hybridized to the 5.9-kb …

Winter Habitat Selection Of Cutthroat Trout (Oncorhynchus Clarki) In A Large Regulated River, Ronald A. Englund

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Microhabitat use by cutthroat trout and macrohabitat use by both cutthroat and rainbow trout were studied i n the Green River below Flaming Gorge Dam during the winters of 1988 and 1989. Microhabitat parameters used by cutthroat trout, such as focal velocity, depth, and fish elevation, differed significantly in eddies, runs, and riffles. Mean focal velocities in runs were 0.79 body lengths/seconds (bl/s), in riffles 0.66 bl/s, and in eddies 0.24 bl/s. Cutthroat trout size also varied significantly with macrohabitat; larger fish were found in riffles.

Macrohabitat use by cutthroat trout and rainbow trout differed significantly among species, macrohabitat types, …

Mathematical Programming Applications In Agroforestry Planning, Laurence H. Reeves

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Agroforestry as a sustainable production system has been recognized as a land use system with the potential to slow encroachment of agriculture onto forested lands in developing countries. However, the acceptance of nontraditional agroforestry systems has been hampered in some areas due to the risk-averse nature of rural agriculturalists. By explicitly recognizing risk in agroforestry planning, a wider acceptance of agroforestry is possible. This thesis consists of a collection of three papers that explore the potential of modern stock portfolio theory to reduce financial risk in agroforestry planning.

The first paper presents a theoretical framework that incorporates modern stock portfolio …

Is Rainbow Trout Condition Influenced By Invertebrate-Drift Density?, Randall B. Filbert

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Users of the Instream Flow Incremental Methodology CTFIM) commonly assume that there is a positive linear relationship between available habitat (WUA) and stream fish biomass. However, several studies have shown a lack cf correlation between WUA and biomass. Such poor relationships may occur if other factors limit fish abundance. Food availability is a potentially important factor limiting abundance of stream fishes and can affect blomass by influencing fish condition (individual weight). I collected rainbow trout (Oncorhynchus mykiss) exposed to different levels of invertebrate-drift density to determine if condition was greater where food was more abundant. I also examined …

A Comparison Of Estimation Procedures For The Beta Distribution, Huey Yan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The beta distribution may be used as a stochastic model for continuous proportions in many situations in applied statistics. This thesis was concerned with estimation of the parameters of the beta distribution in three different situations.

Three different estimation procedures-the method of moments, maximum likelihood, and a hybrid of these two methods, which we call the one-step improvement-were compared by computer simulation, for beta data and beta data contaminated by zeros and ones. We also evaluated maximum likelihood estimation in the context of censored data, and Newton's method as a numerical procedure for solving the likelihood equations …

The Swett Homestead: An Oral History 1909-1970, Eric G. Swedin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Making extensive use of oral interviews with the surviving children, this thesis is an biography of Oscar and Emma Swett and their children, who lived on a homestead in Greendale, Utah, (near Flaming Gorge Reservoir) from 1909 to 1970. The family is representative of a group of families who moved to Greendale and engaged in small-scale cattle ranching. The introduction of new technology changed their lifestyles and homestead economics, while simultaneously Greendale evolved from a rural agricultural environment to become part of a National Recreation Area.

Study Of Ferredoxin And Flavodoxin From Tobacco Leaves And Roots Under Normal And Iron-Stressed Conditions, I-Jen Huang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I purified tobacco leaf ferredoxin from normal and iron-stressed leaves. The oxidized form of ferredoxin from normal leaves had absorption maxima at 268, 327, and 422 nm and a shoulder at 463 nm. The oxidized form of ferredoxin from iron-stressed leaves had absorption maxima at 268 and 329 nm but no absorption maxima in the 400-nm range. Higher ferredoxin content was found with higher chlorophyll content in leaves of the same age.

A protein in tobacco root extract was isolated and found to serve as an electron carrier for ferredoxin-requiring nitrite reduction. This protein had a molecular weight and antigenic …

An Ecological Test Of The Tragedy Of The Commons On Communal Rangeland In The Moroccan Western High Atlas, Lloyd Mendes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I empirically tested an hypothesis derived from a popularized version of Garrett Hardin's "Tragedy of the Commons" paradigm. Some range-development authors predict overgrazing and ecological abuse on all traditional communal rangelands. I estimated forage production, consumption, and season of use on one traditional agdal or intertribal common in the Moroccan Western High Atlas Mountains. Results from 1984-85 do not support the overgrazing predicted by "tragedy" proponents. I argue that the lack of overgrazing is not coincidental but is due to the traditional communal mechanism of controlling season of use.

Heterologous Expression And Characterization Of Three Active Recombinant Fungal Peroxidases From Phanerochaete Chrysosporium Using Baculovirus, Todd M. Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In a collaborative effort with Dr. Steven D. Aust's group at Utah State University, this research is the first to describe the heterologous expression of active peroxidases from the filamentous fungus Panerochaete chrysosporium. The cDNA clones λML-1, λML-6, λML-5 and λMP-1, which had been tentatively identified as fungal peroxidase clones, were subcloned into baculovirus transfer vectors and recombinant Autographa californica nuclear polyhedrosis viruses were constructed which contained copies of these potential peroxidase genes. The recombinant baculovirus clones were used to infect insect cells for the heterologous production of active recombinant enzymes. Three recombinant lignin peroxidases (H2, H6 and H8) …

Comparative Foraging Ecology Of Sheep And Goats In Caatinga Woodland In Northeastern Brazil, Scott L. Kronberg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Small-ruminant production is an important part of the agricultural economy of northeastern Brazil. However, mild-to-severe undernutrition of livestock is an annual occurrence. Goats can tolerate the marginal forage conditions better than sheep, but the mechanisms underlying their superior tolerance are not understood.

An analysis of animal liveweights at the end of the year-long study indicated that reproducing mixed-race goats gained nearly twice (P<.05) the weight of reproducing hair-sheep of the Santa Ynez breed, and non-reproducing goats gained about 1.2 times more (P<.05) weight than non-reproducing sheep. Daily weight gains of lambs were less (P<.10) than those of kids for their first 80 days of life.

In the wet season, reproducing sheep and goats gained similar (P>.05) weight, while non-reproducing sheep gained more (P≤.05) than non-reproducing goats. Non-reproducing goats had greater (P<.05) forage organic matter intake (OMI) than the corresponding sheep in the two wet periods. In the late-wet period, non-reproducing goats had greater (P<.05) digestible energy intake (DEI) than corresponding sheep did but had similar (P>.05) digestible protein intake (DPI) as sheep.

In the dry …

The Effects Of Conditioned Reinforcers On Extinction When Delivered On Schedules Of Extinction, Linda L. Barnard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of the present research was to examine extinction of responding with regard to the rapidity and thoroughness of the process when conditioned reinforcement was available on one of five schedules during extinction. Forty-five mixed-breed pigeons served as subjects with 15 in each of three experiments. Reinforcement training schedules were as follows: Experiment 1, continuous; Experiment 2, fixed ratio 15; Experiment 3, variable-interval one-minute. After training, subjects experienced one of five extinction procedures (here called schedules of extinction) which were as follows: traditional schedule without keylight did not provide conditioned reinforcement; traditional with keylight had the keylight on continuously …

The Importance Of Cover For Juvenile Rainbow Trout In Lentic Systems: Field Observations And An Experimental Study On Predation, Roger Allen Tabor

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Juvenile rainbow trout Oncorhynchus mykiss stocked into mid-elevation reservoirs in Utah are vulnerable to predation from piscivorous fish and birds. I determined how effectively juvenile trout used cover to avoid these predators by (1) direct observations (snorkel transects) of habitat selection in two reservoirs and (2) measurements of survival and growth rates in a pond experiment where adult brown trout Salmo trutta were predators. Observations of juvenile trout were conducted within five weeks of stocking in 1988 and 1989. During the day, juvenile trout were abundant in complex inshore habitats and avoided simple habitats such as sand and gravel. Measurements …

Effects Of Ketoconazole On Uterine Weight And On Unbound Serum Estradiol Relative To Vaginal Cornification In Rats, Leonard L. Hall

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ketoconazole is a broad-spectrum antifungal with oral activity and is documented to block steroid biosynthesis in fungi and mammals.

Estradiol-primed ovariectomized rats lose the estradiol-induced, cornified layer of the vaginal epithelium as a result of ketoconazole treatment. This effect is not explained by current knowledge of ketoconazole's mechanism of action.

Ketoconazole's effect on estradiol's binding to either receptors in target tissues (target-cell receptors) or serum-estradiol-carrying proteins in the aforementioned rats was investigated.

The uterus is responsive to estradiol treatment, which causes an increase in uterine size and weight. This tissue is a sensitive means of studying the effects of ketoconazole …

An Experimental Analysis Of Higher-Order Stimulus Control In Humans, Michael B. Gatch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation explored sane effects of context on the development of stimulus classes and the transfer of stimulus functions to novel stimuli. The research was also intended to demonstrate the utility of current behavioral theories for prediction and control of contextual effects on class formation. In Experiment lA, contextual control of stimulus classes was established successfully in all six college-student subjects. Matching-to-sample training successfully transferred the function of the contextual stimuli to four novel stimuli, whim resulted in the formation of two three-member classes of contextual stimuli. The first portion of Experiment 1B replicated Experiment 1A with three additional subjects. …

The Response Of Coyotes To Novel And Familiar Visual And Olfactory Stimuli, Yiting Zhang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to explore the response v of coyotes (Canis latrans) to certain olfactory and visual stimuli. It was assumed that the findings would be of value in refining techniques used in sampling and controlling coyotes. The specific objectives were to determine (1) if coyotes were more likely to approach and remain in the vicinity of a familiar than unfamiliar scent, (2) if the response to olfactory and visual stimuli differed, (3) if positively reinforcing an approach to the stimuli differentially altered the response to visual and olfactory stimuli, and (4) if the response …

The Effect Of Seasonal Cattle Grazing On California Bighorn Sheep Habitat Use, Melanie J. Steinkamp

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effect of seasonal cattle grazing on a newly reintroduced population of California bighorn sheep (Ovis canadensis californiana) in Big Cottonwood Canyon, Idaho, was studied. The hypothesis that bighorn sheep avoid cattle was tested. The issue of avoidance between bighorn sheep and livestock is arguable. Some studies have found that bighorn sheep avoid cattle while others have found no response of bighorn sheep to cattle.

Evidence was found to document the avoidance of cattle by bighorn sheep. The size of the bighorn's home range and core area decreased with the movement of cattle into areas of high bighorn …

Purification And Immunological Reactivity Of Commercial Microbial Milk Clotting Enzyme Preparations, Chima I. Osuala

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Commercial microbial milk clotting enzyme preparations were purified by immunoaffinity chromatography using purified antibody covalently coupled to porous glass beads as the column matrix. Commercial enzyme preparation diluted in 1 mM sodium acetate buffer at pH 5.0 was then biospecifically adsorbed to the column matrix by end-over-end mixing of the glass-antibody complex in the enzyme solution for 12 h at 5°C. The antibody bound enzyme adsorbed glass beads were soaked in .2 M glycine or ethanolarnine at pH 7.0 to block uncoupled reactive sites on the matrix. Following this, the column was washed with 1 mM sodium acetate …