Digital Commons Network^™

Optimal Fractional Order Proportional And Integral Controller For Processes With Random Time Delays, Varsha Bhambhani

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis developed a new practical tuning method for fractional order proportional and integral controllers (FO-PI / PI^α) for varying time-delay systems like networked control systems (NCS), sensor networks, etc. Based on previously proposed FO-PI controller tuning rules using fractional Ms constrained integral gain optimization (F-MIGO), simultaneous maximization of the jitter margin and integrated time weighted absolute error (ITAE) performance for a set of hundred gain delay time-constant (KLT) systems having different time-constants and time-delay values are achieved. A multi-objective optimization algorithm is used to simultaneously maximize the ITAE factor and jitter margin of the plants at initial …

Seed Banks Of Sagebrush Communities Seeded With Crested Wheatgrass, Kevin L. Gunnell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Crested wheatgrass (Agropyron cristatum [L.] Gaertn.) is one of the most commonly seeded exotic species in the western United States. Although many degraded Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis) plant communities have been seeded with crested wheatgrass during rehabilitation efforts, seed banks of these communities have not been characterized. I sought to characterize and explain the variation among 33 seeded communities in the northeastern Great Basin. Hierarchical clustering and principal components analysis identified four possible seed bank categories in these communities. Seed bank categories varied from high to low crested wheatgrass dominance. The crested wheatgrass-dominated category …

The Correlation Between A Pre-Engineering Student's Spatial Ability And Achievement In An Electronics Fundamentals Course, Mark E. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Though there is ample evidence showing a positive relationship between a student's spatial ability and achievement in many fields of science, technology, and engineering, this study was seeking evidence that a relationship exists between a pre-engineering student's spatial ability and achievement in an electronics fundamentals course.

The importance of spatial ability to mentally design, develop, and manipulate images has been linked to measures of practical and mechanical abilities that are quite useful in technical occupations. Spatial abilities are frequently attributed to creative and higher order thinking skills in science and mathematics. Spatial imagery is tremendously important in art and creative …

Effects Of Targeted Grazing And Prescribed Burning On Fire Behavior And Community Dynamics Of A Cheatgrass (Bromus Tectorum)-Dominated Landscape, Joel M. Diamond

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Studies were conducted to determine the effectiveness of using targeted grazing and prescribed burning as tools to reduce fire hazards and cheatgrass (Bromus tectorum) dominance on rangelands in the northern Great Basin. A field study, with four grazing-burning treatments (graze and no-burn, graze and burn, no-graze and burn, and no-graze and no-burn), was conducted on a B. tectorum-dominated site near McDermitt, Nevada from 2005-2007. Cattle removed 80-90% of standing biomass in grazed plots in May 2005 and 2006 when B. tectorum was in the boot (phenological) stage. Grazed and ungrazed plots were burned in October 2005 and …

Predicting The Growth Potential Of A Shallow, Warm-Water Sport Fishery: A Spatially Explicit Bioenergetics Approach, Samuel Kirk Dahle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Capturing the range of fish consumption and growth potential of large, heterogeneous lentic systems can be challenging due to strong gradients in productivity, the diversity of habits types present, and in some cases, site-specific water quality issues. Cutler Reservoir (Utah, USA) displays a high degree of spatial and temporal variation in physical conditions and potential water quality limitations for fish, including high summertime water temperature and large, diel fluctuations in dissolved oxygen concentrations. The combination of bioenergetics modeling and GIS spatial analysis offers a promising interface for quantifying the fish consumptive and growth potential across a spatially and temporally heterogeneous …

Prediction Of Protein Function And Functional Sites From Protein Sequences, Jing Hu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

High-throughput genomics projects have resulted in a rapid accumulation of protein sequences. Therefore, computational methods that can predict protein functions and functional sites efficiently and accurately are in high demand. In addition, prediction methods utilizing only sequence information are of particular interest because for most proteins, 3-dimensional structures are not available. However, there are several key challenges in developing methods for predicting protein function and functional sites. These challenges include the following: the construction of representative datasets to train and evaluate the method, the collection of features related to the protein functions, the selection of the most useful features, and …

Carbohydrate Derivatives In Antibiotics Research, Yi Liang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In this study, we investigated the potential applications of carbohydrates in the development of new antibiotics. To tackle the problem of multidrug-resistant variants of M. tuberculosis (MDR-TB), we investigated the biosynthesis pathways of trehalose, which has contributed to significant drug resistance. Some new methods were developed for the synthesis of potential inhibitors (6-azido-trehalose and 6,6'-diazido-trehalose) that have been designed to imitate the intermediate molecule (trehalose 6-phosphate, TPP) of OtsA-OtsB pathway. At the same time, some new antibacterial agents based on trehalose have been synthesized. Members of the 1,2,3-triazole family have shown interesting biological properties. Steroid derivatives have been developed in …

Evolutionary Consequences Of The Introduction Of Eleutherodactylus Coqui To Hawaii, Eric Michael O'Neill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The introduction of a species to areas outside its native range can result in ecological and genetic changes of evolutionary significance. The frog Eleutherodactylus coqui was introduced to Hawaii, from Puerto Rico, in the late 1980s and has lost genetic variation in mitochondrial DNA. The extent to which founder effects have influenced phenotypic variation in the introduced range is unknown. In this study I compared phenotypic variation in life-history traits, advertisement calls, and stripe patterns among introduced and native populations of the frog Eleutherodactylus coqui. I also conducted laboratory experiments to determine the influence of genetics and temperature on …

Characterizing Subsurface Textural Properties Using Electromagnetic Induction Mapping And Geostatistics, Hiruy Abdu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Knowledge of the spatial distribution of soil textural properties at the watershed scale is important for understanding spatial patterns of water movement, and in determining soil moisture storage and soil hydraulic transport properties. Capturing the heterogeneous nature of the subsurface without exhaustive and costly sampling presents a significant challenge. Soil scientists and geologists have adapted geophysical methods that measure a surrogate property related to the vital underlying process. Apparent electrical conductivity (EC_a) is such a proxy, providing a measure of charge mobility due to application of an electric field, and is highly correlated to the electrical conductivity of …

Surgical Sterilization Of Coyotes To Reduce Predation On Pronghorn Fawns, Renee Seidler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Coyote (Canis latrans) predation accounts for the majority of neonatal pronghorn (Antilocapra americana) mortality in many areas and may influence local population declines. Current techniques used to manage coyote predation on wildlife species generally focus on lethal control methods. However, these methods may be controversial to the general public. Coyote sterilization is an alternative predation control method which is more acceptable to the public and has been shown to be effective in reducing sheep predation. We hypothesized that surgical sterilization of coyotes may increase pronghorn fawn survival; in the same way it reduces coyote predation on …

Patch-Scale Effects Of An Invasive Ecosystem Engineer On The Structure And Function Of A Eutrophic Stream, Samuel J. Hochhalter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Recent theoretical and technological advances in ecosystem science have dramatically expanded the ways in which scientists can pursue and explore ecological questions. For my thesis research, I integrated the recent theoretical concept of organisms as ecosystem engineers with the relatively recent development of stable isotope tracer tests to ask the question: how does the invasive common carp affect stream ecosystem structure and function? To investigate the structuring role of carp, I measured autotroph seasonal distribution and abundance and macroinvertebrate seasonal abundance and diversity within two stream reaches in Spring Creek, Utah, USA; one with low carp biomass (LCB) and one …

Status And Slaughter: The Psycho-Social Factors That Influence Public Mass Murder, Stephen G. Van Geem

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Even though public mass shootings are relatively rare, they represent an atypical form of violence that is both sudden and yields an unprecedented amount of carnage; for these reasons, an inordinate amount of scholarship has been produced in order to isolate both the causes and effects of these rampages. As there is no clear cut and universal cause, over the past forty years numerous factors have been offered to account for these types of shootings, including bullying, peer relations, family problems, cultural conflict, demographic change, mental illness, gun culture, copycatting, and the media. While there appears to be an element …

Microbial Growth Inhibition And Decomposition Of Milk Mineral And Sodium Tripolyphosphate Added To Media Or Fresh Ground Beef, Rossarin Tansawat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Milk mineral (MM) is a type II antioxidant (metal chelator) that can bind iron and prevent iron catalysis of lipid oxidation. Thus, MM might have microbial growth inhibition effects on iron-dependent bacteria. Objective 1 was to evaluate effects of MM on growth of non-pathogenic iron-dependent bacterial strains (Listeria innocua, Eschericia coli, Pseudomonas fluorescens). MM (1.5 % w/v) did not significantly inhibit growth of Listeria and E. coli. However, growth of Pseudomonas fluorescens was consistently and significantly reduced by ~1 log colony forming units per ml (CFU/ml) with all levels of MM (0.5, 0.75, 1.5 % …

Terrestrial Small Mammals From The Gamba Complex In Gabon: Distribution Patterns And Landscape Influences, Carrie J. O'Brien

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The small mammal communities of central Africa are not well understood, and the southwestern section of Gabon has not been previously surveyed except for some recent work in Monts Doudou. At five sites within the Gamba Complex we set out to 1) document the species of terrestrial rodents (Muridae) and shrews (Soricidae) weighing less than 100 g, 2) compare the community composition between inland and coastal sites, and 3) evaluate our sampling protocols. Using a combination of pitfall lines, Sherman live traps, and snap traps we captured 721 individuals of 12 rodent and 10 shrew species in 15,792 trap-nights. The …

Grandparents As Adult Mentors On Reported Adolescent Risk-Taking Behaviors, Thane R. Goodrich

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Adolescent risk-taking behaviors, both negative and positive, continue to be a point of interest for researchers and of concern for society. Negative risk-taking behaviors threaten healthy adolescent development and may have deleterious effects on the remainder of the adolescent's life. Positive risk-taking behaviors promote healthy development and can aid in pro-social outcomes. Mentoring has been an established means of assisting adolescents through this sometimes difficult stage of life. Researchers have identified those elements which tend to make the greatest impact in mentoring programs. Among those known elements are adults who are found in "naturally" occurring settings. Teachers in schools, religious …

Patterns Of Psychosocial Functioning And Mental Health Service Utilization In Children And Adolescents With Chronic Health Conditions Or Physical Disabilities, Sara M. Hunt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was designed to further understand the psychosocial functioning of youth with chronic health conditions or physical disabilities, their need for and use of mental health services, and possible barriers to receiving needed services. Previous research has suggested these youth experience poorer psychosocial functioning compared to peers without special health care needs, and they also underutilize needed mental health services. A mixed-methods design was implemented consisting of a quantitative parent survey and a qualitative semistructured interview with young adults with special health care needs.

Children demonstrating poorer psychosocial adjustment in this study experienced more problems related to social functioning …

Cascade Lake: A Novel, Camille Marian Pack

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Twenty-two-year-old Macy Oman narrates the book in retrospect from Cascade, Oregon, where she is visiting her mother. Macy's father moved with her to Portland shortly after the accidental death of her brother, Nick, seven years before the narration begins. Macy's mother stayed behind in Cascade. Thematically the work centers on the emotional repercussions of these losses. Macy's, and her older lover Jason's, involvement with Nick's death is unknown to everyone. Her guilt and her mother's perceived betrayal are disabling. Taking her longing for closeness to nature and to her reclusive friend Celia, Macy discovers folklore that inspires a vision quest …

Consequences Of Vegetation Change On The Dynamics Of Labile Organic Matter And Soil Nitrogen Cycling In A Semiarid Ecosystem, Toby D. Hooker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sagebrush-dominated ecosystems are being transformed by wildfire, rangeland improvement techniques, and exotic plant invasions. These disturbances have substantial effects on the composition and structure of native vegetation, but the effects on ecosystem C and N dynamics are poorly understood. To examine whether differences in dominant vegetation affect the quantity and quality of plant organic matter inputs to soil, ecosystem C and N pools and rates of plant turnover were compared among historically grazed Wyoming big sagebrush, introduced perennial crested wheatgrass, and invasive annual cheatgrass communities. Since low soil moisture during the summer may inhibit the microbial colonization of plant detrital …

An Epistemological Checkup: The Explication, Application, And Evolution Of An Integrated Theory Of Couples Therapy, Mckenzie Leigh Christensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

When clinicians practice therapy without a clear theoretical foundation, they lack direction and purpose. When training to be a marriage and family therapist, understanding and clarifying one's integrated theory and practice of therapy is essential. This mixed methods study was designed to elucidate and apply my theory of therapy in order to identify fidelity to my model as well as understand the effects it has on clients. This study also focused on how experiences in each session of therapy influenced the next session.

Three couples who presented for therapeutic services at the Utah State University Marriage and Family Therapy clinic …

Consumer-Driven Nutrient Recycling In Arctic Alaskan Lakes: Controls, Importance For Primary Productivity, And Influence On Nutirient Limitation, Cody R. Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In lakes, fish and zooplankton can be both sources and sinks of nitrogen (N) and phosphorus (P) through the consumption of organic N and P, and subsequent excretion of bioavailable inorganic forms. These source/sink dynamics, known as consumer-driven nutrient recycling (CNR), may, in turn, control the availability of potentially limiting nutrients for algal primary production. In this dissertation I investigate the importance and controls of CNR as a source of inorganic N and P for primary production (Chapter 2). I then examine zooplankton CNR as a mechanism for increasing nutrient mean resident time (MRT) in the mixed layer of lakes …

Watershed-Scale Analysis Of Riparian Buffer Function, Molly Van Appledorn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The ability of riparian buffers to filter undesirable nutrients from upland sources has long been recognized as an important ecosystem service for maintaining or improving water quality, and as a result, many land management strategies have been built around the preservation or restoration of buffer zones. Newly derived flow-path metrics have shown great promise as a way to assess riparian buffer function at the watershed scale but a thorough investigation of metric performance was necessary. The goals of this study were to: 1) test the independence of flow-path metrics from traditional metrics using a spatially extensive, independent sample of watersheds, …

The Relationship Between Education About Dress Practices And Change In Perception Of Self-Concept Related To Dress, Jennifer L. Nielson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The influence of an individual's dress practices on his/her sense of self has been studied for many years. Courses such as the Dress and Humanity course at Utah State University have been developed to educate students on the impact of dress on society. In this study, students in the Dress and Humanity course were given a pre-course and post-course survey to determine if self-perceptions related to dress practices underwent a change over the duration of the semester. Significant differences were found in the categories of body image, evaluating self-esteem, and communication of self to others. A relationship was found between …

Making Healthy Choices: Adolescent Preference Ratings Of School-Based Health Interventions, Nicholas Glover Baird

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study investigated the effect of a Making Healthy Choices lesson on junior high school students' preference rankings of items used to motivate students to increase academic performance. Results indicated that the lesson resulted in increased ranking scores on healthy items. This study used an assessment procedure that may be used to identify healthy rewards that may motivate students to increase academic performance as well as practice healthy decision making to prevent obesity.

Optimization Of Strongly Nonlinear Dynamical Systems Using A Modified Genetic Algorithm With Micro-Movement (Mgam), Xing Wei

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The genetic algorithm (GA) is a popular random search and optimization method inspired by the concepts of crossover, random mutation, and natural selection from evolutionary biology. The real-valued genetic algorithm (RGA) is an improved version of the genetic algorithm designed for direct operation on real-valued variables. In this work, a modified version of a genetic algorithm is introduced, which is called a modified genetic algorithm with micro-movement (MGAM). It implements a particle swarm optimization (PSO)-inspired micro-movement phase that helps to improve the convergence rate, while employing the efficient GA mechanism for maintaining population diversity. In order to test the capability …

Synthetic Studies Of Laulimalide Analogues, Ian Addison Mcalexander

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Chapter 1 provides some background information on the disease area of cancer and current modes of treatment. Chemotherapy treatment is discussed with a focus on the major cellular targets for these drugs: DNA and microtubules. For each target, classes of active compounds are described along with their mode of action. The microtubule stabilizing agent laulimalide is introduced and a case is made for analogue synthesis.

Chapter 2 describes our first generation efforts toward synthesis of des-methyl laulimalide. The target compound is divided into a northern and southern fragment with the synthesis of each fragment described. The preparation of landmark intermediates …

The Bioactive Properties Of Syringomycin E-Rhamnolipid Mixtures And Syringopeptins, Mekki F. Bensaci

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The need for new antimicrobial agents has become important in the last decade due to emerging resistance to a number of conventional antimicrobial agents. New approaches and sources are needed to generate novel and effective antimicrobials. For example, synergistic combinations between two or more agents may lead to new antimicrobial therapies. Furthermore, the increase in health problems caused by the exposure to agricultural crop pesticides and synthetic fungicides and the emerging development of organic farming has increased the necessity to develop natural products than can be used safely in controlling crop diseases.

In this work, I present the first studies …

Sonication Assisted Synthesis Of Oligomannosides, Christabel Tomla Tanifum

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Oligomannosides prevalently exist as cell surface antigens. They play important roles in diseases such as viral infection and cancer, and they have been shown to be useful as candidates for vaccines. HIV, one of the most devastating modern diseases, has a high content of mannose sugars on its envelope glycoprotein gp120. Oligomannosides of the HIV virus, also called Man9, which are found on the glycoprotein gp120, have been shown to play a protective role for the HIV virus, shielding highly conserved protein domains of gp120 from proteolytic attacks. Thus gp120 plays an important role in HIV infection of cells, being …

Hydraulics Of Ideal Drip Irrigation Systems, Evan J. Thompson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The hydraulics of IDEal drip irrigation system components were analyzed under controlled laboratory conditions and the results can be applied to the design of IDEal systems. The hydraulic loss coefficient for the lateral-submain connector valves was determined based on laboratory measurements. It was found that the hydraulic loss due to friction in the lay-flat laterals can be accurately estimated with standard friction loss equations using a smaller effective diameter based on the wall thickness and inlet pressure head. The equivalent length barb loss, expressed as an equivalent length of lateral, was calculated for button emitters, as well as for micro-tubes …

Characterization Of The Substrate Specificity And Mechanism Of Protein Arginine Methyltransferase 1, Whitney Lyn Wooderchak

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Protein arginine methyltransferases (PRMTs) posttranslationally modify protein arginine residues. Type I PRMTs catalyze the formation of monomethylarginine (MMA) and asymmetric dimethylarginine (ADMA) via methyl group transfer from S-adenosyl methionine onto protein arginine residues. Type II PRMTs generate MMA and symmetric dimethylarginine. PRMT-methylation affects many biological processes. Although PRMTs are vital to normal development and function, PRMT-methylation is also linked to cardiovascular disease, stroke, multiple sclerosis, and cancer.

Thus far, nine human PRMT isoforms have been identified with orthologues present in yeast, plants, and fish. PRMT1 predominates, performing an estimated 85% of all protein arginine methylation in vivo. Yet, the substrate …

Feasibility Analysis Of Seed Production For Use In Re-Seeding Land Burned In Wildfires In The Great Basin Region Of The United States, Benjamin Jay Young

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Native and introduced grass and shrub species are grown for seed production in the Great Basin region of the United States. The purpose of this research is to evaluate the profitability and risk associated with the production of five different species of grasses and shrubs which are used in rehabilitation following wildfires. Enterprise budgets are constructed for both the establishment and production years. Returns above operating costs are compared to other crops produced in the same region. Production and market risks are discussed. Returns and risks are evaluated using an expected value model which compares risk and return between species, …