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The Paleoecology And Geomorphology Of Holocene Deposits Of The Southern Malad River, Box Elder County, Utah, Ann Schaffer Elder

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Widespread Lake Bonneville sediments have been modified by river aggradation and degradation associated with Holocene fluctuations in the Great Salt Lake. Exposures of exceptionally abundant and well-preserved molluscan deposits in the Bear River Valley, Utah, allow detailed paleoenvironmental reconstruction of Holocene environments. The exposed basal unit consists of largely unfossiliferous deltaic silts and clays deposited during Lake Bonneville time (roughly 11,000 - 13,000 yr B. P.). An unconformity representing at least 2000 yr separates the deltaic material from overlying highly fossiliferous stream sands. Eight species of molluscs, comprising a single community, occupied this low energy stream environment at 7690 ± …

A Comparison Of Two Linear Nonparametric Regression Techniques, Sylvain Sardy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presented a useful tool in regression. Nonparametric linear regression techniques were described in the general context of regression. A comparison of two of these techniques, kernel regression and iterative regression, showed various aspects of nonparametric linear regressors.

Effects Of Knowledge Of Accountability In Mastery Learning Programs On Academic Achievement, Goal Setting Characteristics, And Locus-Of-Control Orientation, Donn C. Ritchie

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During the past quarter century, over 1000 articles have documented changes in student behaviors related to participation in mastery learning programs. Although the results have been generally positive, a debate continues as to the cause for increased student performance: Are results due to changes in how students attend to the information, or simply due to increased study time as a result of remediation?

In this study, a videodisc-based program in fractions was used with fifth-grade students. The videodisc-based instruction was chosen to help minimize differences in instructional materials, instructional time, and instructional delivery. A pretest-posttest, control-group design was used to …

Factors That Explain Changes In The Level Of Human Capital Of Children With Disabilities, Linda D. Goetze

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation combines concepts from the human capital and early intervention literature to develop a theoretical and empirical model of child development relationships. This model is empirically estimated using data from the Early Intervention Research Institute's Longitudinal Study on the effects of intervention for young children with disabilities. The model is estimated using Ordinary Least Squares (OLS) relating the Battelle Developmental Inventory (BDI) scores to child, family, and early intervention variables. These relationships are also examined using a type of Sequential Method of Moments (SMM) estimation strategy that accounts for data and other problems such as endogeneity, censoring, and selectivity. …

An Embedded Ring Approach To The Vibrational Dynamics Of Disordered Two-Dimensional Materials, Timothy Edwin Doyle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A theoretical approach was developed to model the vibrational dynamics of amorphous, two-dimensional materials. The materials were modeled as continuous random networks (CRN's) comprising an assemblage of planar rings of diverse size. In-plane vibrational modes for symmetric 4-, 5-, 6-, 7-, and 8-membered rings were examined. Vibrational states of isolated rings were modified by coupling the rings to a continuous network to represent rings embedded in a CRN. An effective force constant was used to couple the ring vibrations to the network's collective motions. Potentials were approximated with the use of a central force model (bond-stretching force constant) and a …

Economic Analysis Of Dryland Wheat Tillage Practices In Box Elder County, Utah, Michael Dale Bond

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to determine the economic viability of various dryland wheat tillage systems, many of which were developed from years of cooperative research efforts.

In the study three conventional tillage methods were analyzed along with ten conservation tillage practices. The study farm consisted of 2000 acres, of which 1000 acres are classified as land 1 and its wheat yield is assumed to be 35 bushels per acre for non-continuous tillage methods and 23 bushels per acre for continuous tillage methods. The remaining 1000 acres are classed as land 2 and its assumed wheat yield is 30 …

Optimization Of Ranch Management Alternatives In Utah, Scott G. Evans

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to determine the optimum combination of various cattle production, range forage, and crop harvesting alternatives available to ranch owners and managers in Utah. While many promising alternatives are available, determining which alternatives to implement is difficult because the total ranch operation must be considered.

Linear programming (LP) is a tool available to ranch managers which allows the profit maximizing combination of improvements to be easily determined. LP allows ranchers to examine the entire ranch operation and to reduce the amount of risk and uncertainty involved in the decision making process.

The typical Utah ranch …

Validation Of The Use Of The Rapid Speech Transmission Index (Rasti) In Elementary School Classrooms, Aparna Rao

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The aim of this study was to assess the validity of an objective method of speech intelligibility, the Rapid Speech Transmission Index (RASTI), in elementary school classrooms, The RASTI can be obtained more quickly than subjective measures of speech intelligibility and has been shown to be highly valid with adult listeners in auditoriums. In this study RASTI values were correlated with scores on a subjective test of speech intelligibility, the word intelligibility by Picture Identification (WIPI) test, for 45 students in two elementary classrooms (grades 1 through 3 and grade5). Results indicated that the RASTI value is a poor predictor …

New Syntheses Of Diaryl Ethers, Tyrosinols, B-Hydroxytyrosinols, L,L-Isodityrosinol And L,L-Isodityrosine-Derived Agents Via The Diels-Alder Reaction, Xianqi Feng

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Syntheses of diaryl ethers were approached by use of a Diels-Alder reaction employing a new type of diene attached with an aryloxy group. Thus, 2-methyl-3-phenoxybutadiene (90b ), 2- methoxy-3-phenoxybutadiene (92b) and (4S)-3-(t- butyloxycarbony1)-2 ,2-dimethyl-4-( 4-(3-methoxy-1,3 -butadienyl-2- oxy )phenylmethyl]oxazolidine (93b) were synthesized in ~65% yields by methylenation of the carbonyl function in the corresponding 2- substituted acrylate aryl ester using Tebbe's reagent. The 1,3- bis[(trimethylsilyl)oxy ]-2-phenoxybutadiene (105) was made from 1-phenoxy-2-propanone (101) by a sequence of formylation and enolsilylation. Methyl propiolate (107) and dimethyl acetylenedicarboxylate (113) were heated at reflux with diene 9 0 b and 92b in toluene to provide …

Effects Of Stabilizers And Ph Adjustments On Milk Proteins In Uht-Treated Citrus Juice/Skim Milk Blend Drink, Sandra M. Newman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A UHT-processed skim milk (85%)/orange juice (15%) drink was developed. Product integrity and stability were maintained by two methods. Proper homogenization of the blend before UHT processing stabilized a drink formulation containing .25% carboxymethyl cellulose and .025% carrageenan. Adjusting the pH of the blend (pH 6.3 and 6.5) resulted in a different stabilization. After 28 days at room temperature, settling of milk solids was 5.2% of volume height in the prehomogenized sample and 86.9% of volume height in the same blend that had not been homogenized prior to UHT processing. After storage, the two treatments were analyzed to verify that …

A New Method For Measuring Macroparticulate Systems Applied To Measuring Syneresis Of Renneted Milk Gels, Jonathan R. Maynes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Syneresis is an integral part of cheese manufacture. The rate and extent of syneresis affect the properties of cheese. There are many factors that affect syneresis, but measured results vary because of inaccuracies in measuring techniques. To better control syneresis, an accurate mathematical description must be developed. Current mathematical models describing syneresis are limited because of inherent error in measuring techniques used to develop them. Developing an accurate model requires an accurate way to measure syneresis.

The curd becomes a particle in a whey suspension when the coagulum is cut. The most effective technique to measure particle size, without interference, …

Groundwater Flow In Closed Desert Basins: Insights From Numerical Experiments, Ying Fan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research examines density driven groundwater flow (free convection) in closed desert basins as controlled by various physical factors. It addresses three issues. The occurrence of free convection under field conditions is first examined, based on an extensive literature review of field investigations. It discusses the evidence for or against the hypothesis of free convection and the various physiographic factors that determine the conditions for free convection. The research then turns to a more quantitative and systematic investigation of the closed basin hydrogeologic system. With dimensional analysis, the numerous variables in the system are transformed into fewer dimensionless and physically …

The Effect Of Dyad Interaction And Marital Adjustment On Cognitive Performance In Everyday Logical Problem Solving, Donna R. B. Rogers

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The theory of formal operations as a final stage of adult development has come under criticism for various reasons, primarily the overemphasis on logical thought processes which are based on invariant and absolute rules within a closed system. Everyday problems, in contrast, are typically "open-ended" and are defined by the context in which they are embedded.

The purpose of this study was to investigate cognitive behaviors that occurred between two individuals as they cooperatively worked together to solve logical problems. Of interest were the effects of marital adjustment on cognitive performance, the relation between social behaviors, marital adjustment, and cognition, …

Effects Of Polyacrylamide On Rangeland Soils And Plants, Saud Leily R. Al-Rowaily

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objectives of this study were to determine the effects of two forms of polyacrylamide (PAM) conditioners (Cross-linked and Non-cross-linked PAM) on evaporation, saturated hydraulic conductivity, water retention, crust and crack formation of soils, seed germination, and seedling and tubeling growth.

The two PAM conditioners, 0.2% concentration by weight, were mixed with seven soils of different textures (sandy loam, silt, silty clay loam, silt loam, fine sand, medium sand, and coarse sand) to investigate the effects on evaporation, saturated hydraulic conductivity, and water retention. Soil samples of different textures were brought to field capacity and placed in a growth chamber …

The Influence Of Redd Distribution And Microhabitat Availability On The Distribution And Abundance Of Young-Of-The-Year Trout In The Green River, Utah, Michael J. Buntjer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Redd distribution, redd density, and physical habitat were used to explain the distribution and abundance of young-of-the-year (YOY) brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss) in the Green River, Utah. The importance of variables at both a microhabitat and macrohabitat scale were assessed using stepwise regression analysis. Availability of cover (rock and vegetation) and proximity to spawning sites were the most important variables used to explain the distribution and abundance of YOY brown trout and rainbow trout. In addition, YOY brown trout and rainbow trout occupied specific microhabitats and showed patterns of use for …

Dynamic Multi-Species Animal Habitat Modeling With Forest Succession Models, Stephen A. Compton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research determines and demonstrates the ability to simulate dynamic multi-species animal habitat suitability with forest succession models. A literature review of dynamic animal habitat models is presented. The structure of an existing forest simulation model (MASS10) was modified from a basal area-based model to a volume-based model (DYNAM10). The forest model was calibrated using data from permanent-plot growth and vegetation samples collected by USDA Forest Service Forest Survey procedures. The theoretical growth parameters used to simulate stand development were validated. Predictions of DBH and height growth, as well as stand-level behavior, were verified. A subroutine, VEGDYN, was added to …

Soil Heterogeneity And Its Exploitation By Plants, Robert B. Jackson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In this dissertation I first examine the ability of individual plants in the field to garner localized soil nutrients. I then measure actual soil variability around perennial plants and use various statistics to quantify the scale and degree of that variability.

Soil patches on opposite sides of Pseudoroegneria spicata tussocks were treated with distilled water or a nutrient solution containing N, P, or K in three field experiments. When P was augmented in the enriched soil patches, rates of P uptake increased significantly for roots from enriched patches compared with roots in control patches. Rates of ammonium and potassium uptake …

Sedimentology And Community Structure Of Reefs Of The Yucatan Peninsula, Mexico, Matthew J. Novak

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Holocene carbonate sediments from Mexican reefs in the Caribbean and Gulf of Mexico display variations in constituent composition, texture and mineralogy which are related to their locations on the reefs. Samples were collected at barrier reef environments at Akumal and Chemuyil, on the northeast coast of the Yucatan Peninsula; at the oceanic atoll of Chinchorro, off the southeast coast of the peninsula; and at the shelf atoll of Alacranes, in the Gulf of Mexico. Samples were collected through a depth range of 0-40 m, which encompasses back reef, shallow fore reef, and deeper fore reef environments.

Constituent-particle analysis of reef …

Spatial And Temporal Variations Of The Pilot Valley Playa Interpreted From Remotely Sensed Images, Llyn Doremus

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the Basin and Range Province, the geologic regime of the Pilot Valley, linear trending block faults have isolated many valleys both topographically and hydrologically. Discharge from these arid, closed basins occurs only as evaporation. Minerals dissolved in discharging fluid are precipitated at the valley floor as the liquid evaporates. The resulting salt flats and high density brines are known as playas.

The Pilot Valley Playa surface was sampled concurrently with the recording of a Thematic Mapper remotely sensed image to define the surface conditions that correspond to image data. An association was found between the band 7 (infrared wavelength …

A Maple Package For The Variational Calculus, Cinnamon Hillyard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The HELMHOLTZ package, written in Maple V, is a collection of commands to support research in the variational calculus. These commands include the standard operators on differential forms, Euler-Lagrange operators, homotopy operators, Lie bracket, Lie derivatives, and the prolongation of a vector field. We give a brief introduction to the variational calculus. We describe each of the commands in the HELMHOLTZ package completely along with numerous examples of each. Applications of the package include verification of symmetry groups for differential equations, solving the inverse problem of the calculus of variations, computing generalized symmetries, and finding variational integrating factors. A complete …

Inverse Problem In Porous Medium Using Homogenization, Helen Alkes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The problem under consideration is that of obtaining a representation of the permeability of a porous medium which is heterogeneous and anisotropic from limited information. To solve this inverse problem we propose the use of two different pieces that work together. A simulated annealing algorithm is presented and coupled with an homogenization technique; together these solve the problem which was posed. Further, numerical simulation results are presented illustrating the use of the simulated annealing algorithm as well as a coupling with the homoginization technique. This study illustrates that the performance of the annealing algorithm is enhanced with usage of homogenization.

Disconjugacy And Oscillation Theory Of Linear Differential And Difference Equations, Yuhua Xu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation is both a literature survey and a presentation of new and independent results.

The survey gives an overview of disconjugacy and oscillation theory for linear differential and difference equations with an emphasis on comparing the theory of difference equations to the theory of differential equations. Second order scalar equations, higher order scalar equations, matrix equations (systems) and Hamiltonian systems are discussed. A chapter on three-term recurrences of systems is also included. Both similarities and differences between differential and difference equations are described.

The new and independent results are for Hamiltonian systems of difference equations. Those results include the …

Hopf Bifurcation In A Parabolic Free Boundary Problem, Yoon-Mee Lee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We deal with a free boundary problem for a nonlinear parabolic equation, which includes a parameter in the free boundary condition. This type of system has been used in models of ecological systems, in chemical reactor theory and other kinds of propagation phenomena involving reactions and diffusion.

The main purpose of this dissertation is to show the global existence, uniqueness of solutions and that a Hopf bifurcation occurs at a critical value of the parameter r. The existence and uniqueness of the solution for this problem are shown by finding an equivalent regular free boundary problem to which existence …

Mobilization Of Iron Enhances The Iron-Dependent Biochemical Reactivity Of Asbestos In Vitro And Contributes To The Cytotoxicity Of Asbestos In Cultured Cells, Loren Glen Lund

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Asbestos related research began approximately 60 years ago, yet, the mechanism(s) by which asbestos exerts its biological effects is not well understood. The hypothesis upon which this dissertation is based is that mobilization of iron from asbestos enhances the iron-dependent biochemical reactivity of asbestos in vitro and contributes to asbestos-dependent cytotoxicity. The specific aims for this hypothesis were, 1) to determine whether iron was responsible for the biochemical reactivity of asbestos in vitro and asbestos-induced cytotoxicity in cultured cells, and 2) to determine whether mobilization of iron from asbestos enhanced the reactions catalyzed by asbestos in vitro and contributes to …

Desert Bighorn Sheep And Riverboat Interactions In Cataract Canyon, Utah, Mark C. Stanger

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I studied desert bighorn sheep (Ovis canadensis nelsoni) behavior and habitat use in response to boating activities during 1985. The percent of total observed time in attention behavior before the boating season, during the boating season, and while riverboats were< 0.8 km from bighorn sheep groups was 1, 1.4, and 12.2, respectively. Estimated energy expenditure did not significantly differ for high riverboat pressures (2 > 0.2) or seasonal comparisons (2 > 0.1). Habitat use significantly differed for proximity to the river, which was probably related to the summer use of the river for drinking. Moderate, minor, and no responses to passing riverboats were observed 3, 39, and 58%, respectively. Responses to riverboats did not significantly differ according to time of day (2 > 0.15) or …

After Prayer And Praise: The Record Book Of The Alexandria Baptist Church: 1803-1816, Jennifer Jaquelyn Ione Fasy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As the earliest surviving record of an urban Tidewater Baptist church, the Alexandria minute book offers historians insight on the leadership and concerns of urban Baptists around 1800. This congregation, largely white women, middle class white men, and black people, slave and free, offered its members a greater equality than they could find elsewhere. This thesis explored these strains of equality and found that the members, especially the women, exercised power within the Church greater than they could command without. The second half of this project provided an accurate transcript of this record book. Any information available on members who …

Relationship Between Villous Shape And Mural Structure In Neutron Irradiated Small Intestine, K. E. Carr, J. S. Mccullough, A. C. Nelson, S. P. Hume, S. Nunn, H. H. M. Kamel

Scanning Microscopy

Previous work on irradiation of mouse small intestine has assessed the changes produced by counting crypts/microcolonies, scoring villous shape or examining morphological changes in specific parts of the wall.

This paper used scanning and transmission electron microscopy to study the effects of whole body irradiation with 5 Gy neutrons on the surface and internal features of the intestinal wall of CFLP mice, 1 day, 3 days and 7 days after treatment.

Empirical scores from the ultrastructural findings were inserted into a Morphological Index display calculated from analytical data based on cell counts and area measurements obtained from resin histology sections. …

Bulk And Surface Singularity Indices In The Alkali Metals, G. K. Wertheim, D. Mark Riffe, P. H. Citrin

All Physics Faculty Publications

Photoemission data from (110) films of Li, Na, and Rb, in which the signal from the first atomic layer is well resolved, show that the core-hole-screening singularity index is ∼40% larger at the surface than in the bulk for all three metals. This result, which is indicative of the more atomiclike character of metal surface atoms, in general, is particularly large for the alkali metals because their conduction-electron screening is mainly s-like. In addition to quantifying the difference in screening at the surface, the data provide bulk singularity indices of 0.22, 0.16, and 0.14 for Li, Na, and Rb, respectively. …

The Interpretation Of X-Ray And Electron Signals Generated In Thin Or Layered Targets, R. H. Packwood, G. Remond

Scanning Microscopy

This work outlines the development of a comprehensive theory for the electron probe microanalyser and scanning electron microscope or SEM, that is intended to serve as a framework of understanding for those employing electron beam methods and as a basis for improved correction procedures. There is particular emphasis on applications to layered and non-uniform specimens. Starting from a simple Gaussian depth distribution of electrons and making assumptions about the X-ray production, a series of predictions of X-ray and electron signals are made for various target configurations. When compared with experimental measurements a series of interesting discoveries follow, which, taken altogether, …

Thermal And Surface Core-Electron Binding-Energy Shifts In Metals, D. Mark Riffe, G. K. Wertheim, D. N. E. Buchanan, P. H. Citrin

All Physics Faculty Publications

High-resolution photoemission spectra from the shallow core levels of alkali metals and of In have been obtained between 78 K and room temperature. The data yield values for the alkali-metal surface-atom core-level shift and show thermal shifts of comparable size for bulk and surface. The positive surface shifts are due to the spill-out of conduction-electron charge, which is responsible for the surface dipole layer. The surface shifts are in good agreement with values obtained from a Born-Haber cycle expressed in terms of surface energies. The thermal shifts are proportional to the lattice expansion, and arise from both initial-state and final-state …