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Does Non-Steroidal Anti-Inflammatory Drug (Nsaid) Use Affect Dementia Progression And Survival Rates In Alzheimer's Disease? The Cache County Study, Trevor R. Buckley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Alzheimer's disease (AD) has multiple factors that contribute to the disease process. Among these is a state of chronic inflammation that is endured by the brain during the aging process. The use of non-steroidal anti-inflammatory drugs (NSAIDs) decreases the amount of neuroinflammation sustained by the brain, and greater levels of NSAID use have been demonstrated to be associated with decreased probability of developing AD. This study looked at whether greater rates of NSAID use were also associated with decreased rates of cognitive and funtional decline and survival in a population-based sample of persons with AD. Linear mixed models failed to …

Environmental Sensor Anomaly Detection Using Learning Machines, Erick F. Conde

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The search for improvements in the quality assurance/quality control (QA/QC) of real-time environmental measurements has been a field well exploited in recent years. These measurements describe actual environmental conditions and processes that provide relevant information upon which water quality management decisions are based. In situ sensors (located at the site of interest) are commonly used for such real-time measurement purposes. However, the performance of these types of sensors can be affected by such things as human factors, lack of necessary maintenance, flaws on the transmission line or any part of the sensor, and unexpected changes in the sensors surrounding conditions. …

Effects Of Tannin-Containing Feed On Haemonchous Contortus In Sheep And Its Behavioral Implications, Jessica A. Juhnke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Herbivores prefer foods that supply required nutrients and avoid those with excess nutrients and plant secondary compounds (PSC). Nevertheless, PSC such as condensed tannins can provide beneficial medicinal effects to herbivores. The objectives of this study were to determine: 1) if parasitized lambs increased preference for a tannin-rich food after they experienced the beneficial antiparasitic effects of tannins relative to parasitized lambs that did not experience such benefits, 2) if preference for the tannin-containing food in the former group decreased when parasite burdens subsided, and 3) if the tannin-enriched food decreased parasitic burdens.

Twenty-two lambs were familiarized with beet pulp …

Molecular Interactions Of Salmonella With The Host Epithelium In Presence Of Commensals, Prerak T. Desai

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Food-borne infections are a major source of mortality and morbidity. Salmonella causes the highest number of Food-borne bacterial infections in the US. This work contributes towards developing strategies to control Salmonella by (a) defining receptors used by Salmonella to adhere to and invade the host epithelium; (b) developing a host receptor based rapid detection method for the pathogen in food matrix; (C) and defining mechanisms of how probiotics can help alleviate Salmonella-induced cell death in the host epithelium.

We developed a cell-cell crosslinking method to discover host-microbe receptors, and discovered three new receptor-ligand interactions. Interaction of Salmonella Ef-Tu with …

Have Introduced Brown Trout (Salmo Trutta) Affected Native Aquatic Vertebrates In Western United States Streams?, Nora K. Burbank

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The introduction of exotic species to areas outside of their native range is one of the greatest threats to the biodiversity of native freshwater organisms. Exotic species have outcompeted native species for resources such as food and shelter, and in some cases these interactions have resulted in local extinctions or reductions in abundance of those native species. Brown trout are native to Eurasia, but have been introduced to much of the rest of the world, including the United States. In some parts of their introduced range, brown trout have substantially reduced the abundance and home ranges of some native fish …

Optimization Of Dissolved Air Flotation For Algal Harvesting At The Logan, Utah Wastewater Treatment Plant, Andrew R. Elder

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Research being completed at the Logan, UT wastewater treatment plant could provide a locally-sourced gasoline replacement by collecting algae that grows naturally. This process would also provide the City of Logan with a method to meet certain standards set by the state of Utah.

Problem and proposed solution:

The water leaving Logan’s wastewater treatment plant has high levels of phosphorus and nitrogen, two elements that are found in all wastewater treatment plants. These two substances need to be controlled, because they kill fish and cause pond scum to grow in recreational reservoirs downstream. A unique method has been found to …

An Assessment Of Vegetation Metrics And Plot Types To Measure Seasonal Variation And Grazing Effects On Riparian Plant Communities, Caroline M. Laine

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Monitoring changes in vegetation is important on public lands. Observing how plant communities respond to changes in land management can give insightful information about which management practices are sustainable. Because water is scarce in the western United States, many land managers focus their monitoring efforts along streams. However, monitoring streamside vegetation is challenging due to a variety of factors and can be confounded by factors such as seasonal climate variation and management activities, like cattle grazing.

In vegetation assessment, there are a variety of measurements that are taken to glean valuable information. Some attributes of interest include how much vegetation …

The Effects Of Early Identification And Intervention On Language Outcomes Of Children Born With Hearing Loss, Catherine A. Callow-Heusser

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study included a comprehensive review of the literature in which the effects of early identification of hearing loss and intervention on language outcomes were investigated. Previous reviews of studies were not comprehensive in their coverage and did not include a common measure for comparing results across studies. Without a more rigorous analysis of the primary research, conclusions drawn from these reviews are tenuous. The review of primary studies showed they exhibit many methodological problems including weak experimental designs, small sample sizes, attrition or questionable sample selection methods, differences in length of treatment and characteristics of the participants, and inadequate …

Assessment Of Colorado’S Wilderness Areas: Manager Perceptions And Remoteness Modeling, Gary D. Vaughn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study assessed visitor use levels and resource and social conditions in wilderness areas across the State of Colorado using existing and collected spatial data. This is the first attempt to spatially assess wilderness conditions at the state level. A state-wide assessment of wilderness conditions allows local and regional managers to make informed regional decisions and to prioritize and direct their time and energy efficiently. This assessment clarifies the recreational use and impacts across the state. This study consists of two projects: 1) managers’ perceptions of the location and extent of resource and social condition problems; and 2) a geographic …

A Dynamic State Metabolic Journey: From Mass Spectrometry To Network Analysis Via Estimation Of Kinetic Parameters, Arockia Ranjitha Dhanasekaran

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The term "metabolism" refers to the chemical processes occurring in a living organism to convert the food consumed into the energy needed to maintain a living state. Metabolism consists of two states, namely, a dynamic state and a steady state. In the dynamic state, the rate of chemical conversion of a substance is proportional to the amount of substance available, whereas in the steady state this rate is constant and independent of the amount of substance present (Chapter 4 Figure 1). Like all other fields of engineering, metabolic engineering involves the analysis and synthesis of metabolism. Molecular biological tools for …

Orchard Floor Management, Marc A. Rowley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Managing fruit orchards involves both the management of the orchard trees, and the orchard floor. Orchard floor management is vital to tree health, yield and fruit quality. Current standard management practices include maintaining a vegetation free tree row and a grass-covered alleyway. This system effectively controls weeds and creates a favorable environment for the fruit trees. However, limitations to standard orchard floor practices are that the grass alleyway provides no nutrient benefit, and current practices do not readily lend themselves to organic management. Alternative in-row and alleyway systems are requisite to creating improved orchard floor management systems.

Three different approaches …

Effect Of Voluntary Exercise And Diet On The Unfolded Protein Response In The Brain Of Mice, Yu Ho Kim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The medical costs for many chronic diseases are increasing dramatically and placing a major financial burden on nations and individuals in both developed and developing countries. A number of chronic diseases, such as obesity, type 2 diabetes and some neurodegenerative diseases are all attenuated by a history of physical activity suggesting that they may be interconnected in some way. It has been suggested that cellular stress is a major factor promoting these chronic diseases.

Cellular stress occurs in a specific compartment within the cell, the endoplasmic reticulum, whose normal function is in the synthesis and folding of proteins into the …

The Relationship Of Acculturation And Acculturative Stress In Latina/O Youths’ Psychosocial Functioning, Marsha Tafoya

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was conducted to better understand how acculturation and acculturative stress are related to self-esteem, depression, substance use, and substance use problems in 206 Latina/o youth. Acculturation is the social and psychological process of change that occurs when an individual or group comes in contact with a different culture. The acculturation process can be positive, improving one’s life chances in the new culture, or it could be negative due to the challenging nature of change and adaptation to new cultural and social expectations. This difficulty creates a type of stress, called acculturative stress that has been found to be …

The Effects Of 24r, 25-Dihydroxyvitamin D3 And 24s, 25-Dihydroxyvitamin D3 On Phosphate Transport In Vivo, Yu Meng

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research studied the effects of the two isomers of 24,25(OH)₂D₃ on phosphate absorption in vivo to increase our understanding of the effects of 24,25(OH)₂D₃ on phosphate transport in vivo, and its two isomers. The current work demonstrates that 24R,25(OH)₂D₃ is capable of decreasing phosphate absorption after a 1h injection in vivo and 24S,25(OH)₂D₃ can increase phosphate absorption after a 5h injection, but this stimulation disappears at time points after 5h.

Since 24,25(OH)₂D₃ is made in vitamin D-replete animals, the observation that 24R,25(OH)₂D …

The Biogeography Of Marbled Godwit (Limosa Fedoa) Populations In North America, Bridget E. Olson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The mission of the U.S. Fish and Wildlife Service (USFWS) is working with others to conserve, protect, and enhance fish, wildlife, plants, and their habitats for the continuing benefit of the American people. Toward fulfillment of that mission, a priority of the USFWS is conservation and management of migratory birds. Effective conservation actions to ensure the continued existence of a species on the landscape cannot be designed without first understanding basic life history characteristics of a species. It is common in the case of migratory birds, that we lack understanding of some of their elemental biological traits.

The Marbled Godwit, …

Causes And Consequences Of Plant Spatial Patterns On Natural And Experimental Great Basin (Usa) Plant Communities, Andrew P. Rayburn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The processes by which plant spatial patterns are formed, and the effects of those patterns on plant community dynamics, remain important areas of research in plant ecology. Plant spatial pattern formation has been linked to many ecological processes that act to structure plant communities at different spatiotemporal scales. Past studies of pattern formation are common, but recent methodological advances in data collection and analysis have permitted researchers to conduct more advanced observational studies of pattern formation in space and time. While studies of the effects of plant spatial patterns were formally rare, they have increased in the last decade as …

Analysis Of The Import, Export, And Bioavailability Of Nitrogen And Phosphorus Within Pineview Reservoir, Brady K. Worwood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was conducted to provide new and useful data about Pineview Reservoir and its watershed, produce water and phosphorus (P) budgets for Pineview Reservoir, test the validity of conclusions made in the Pineview Reservoir Total Maximum Daily Loading (TMDL) document, and create estimates of nitrogen (N) loading to the reservoir from both surface and ground water sources. The production of the water and P budgets, as well as the N loading estimates, was accomplished by measuring flow, nitrate, ammonium, total phosphorus (TP), and soluble reactive phosphorus (SRP) that was entering and exiting the reservoir through surface water sources and …

Optimization Of A Low Reynold's Number 2-D Inflatable Airfoil Section, Todd A. Johansen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A stand-alone genetic algorithm (GA) and an surrogate-based optimization (SBO) combined with a GA were compared for accuracy and performance. Comparisons took place using the Ackley Function and Rastrigin's Function, two functions with multiple local maxima and minima that could cause problems for more traditional optimization methods, such as a gradient-based method. The GA and SBO with GA were applied to the functions through a fortran interface and it was found that the SBO could use the same number of function evaluations as the GA and achieve at least 5 orders of magnitude greater accuracy through the use of surrogate …

Seasonal Transport Of Suspended Solids And Nutrients Between Bear River And Bear Lake, Cody M. Allen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I measured inflows and outflows of nutrients and suspended solid through the wetland complex, known as Dingle Marsh, at the Bear River Migratory Bird Refuge between October 2007 and September 2008. My analysis of changes throughout the year will help Dingle Marsh managers adjust the timing and volume of water movement between Bear River and Bear Lake to meet defined refuge goals, such as improving bird or other animal habitat. These results could also be used to protect Bear Lake’s water quality.

Automated samplers took readings of dissolved oxygen, turbidity, pH and water temperature every 30 minutes. These values were …

A Case Study Of Organizational Change: College Restructuring In Response To Mandated Department Eliminations, Brandy Dyan Smith

UNLV Theses, Dissertations, Professional Papers, and Capstones

Faced with unprecedented budget cuts, Western University had implemented vertical cuts in the Spring of 2010 resulting in the elimination of two departments within their College of Education. Western University was not alone in its struggle. Institutions nationwide were coping with similar financial constraints, with freezes, consolidations, and eliminations becoming commonplace and threatening institutional quality.

The issue of how colleges and the leaders, groups, and individuals within them cope, process, and reorganize following eliminations has quickly gained importance, although there are few empirical studies to guide such changes. The existing literature on restructuring, particularly adaptability and change processes, has focused …

A Polymerase Chain Reaction Method For The Detection Of Selenomonas Noxia, Arthuro Mehretu

UNLV Theses, Dissertations, Professional Papers, and Capstones

In recent studies, periodontal health has been linked to being overweight and/or obese. Among common oral bacteria, Selenomonas noxia has been implicated in converting periodontal health to disease. Selenomonas spp. have also been found in gastric ulcers, and were misdiagnosed as Helicobacter -like organisms, but no further studies were conducted. The increasing clinical and epidemiological importance of S. noxia necessitates the development of a rapid detection method. In this study, a TaqMan 16S rRNA based real-time Polymerase Chain Reaction (PCR) method was developed, optimized and evaluated for the rapid and specific detection of S. noxia . The 16S PCR assay …

Retrospective Evaluation Of Microbial Presence In Existing Saliva Repository: A Pcr Based Molecular Survey Of Oral Microbial Populations From Existing Saliva Samples, Jay Ericksen Davis

UNLV Theses, Dissertations, Professional Papers, and Capstones

The overall purpose of this research project is to explore the link between oral health and disease in the University of Nevada, Las Vegas - School of Dental Medicine (UNLV-SDM) clinic patient population. More specifically, the population of interest is the UNLV-SDM orthodontic clinic patient population, which is mostly composed of adults, females, and minorities. The University of Nevada, Las Vegas, School of Dental Medicine, with more than 70,000 active patients and a post-graduate specialty program in Orthodontics is uniquely positioned to perform this type of oral health epidemiology survey, as well as targeted oral microbial testing among populations within …

Automating Construction And Selection Of A Neural Network Using Stochastic Optimization, Jason Lee Hurt

UNLV Theses, Dissertations, Professional Papers, and Capstones

An artificial neural network can be used to solve various statistical problems by approximating a function that provides a mapping from input to output data. No universal method exists for architecting an optimal neural network. Training one with a low error rate is often a manual process requiring the programmer to have specialized knowledge of the domain for the problem at hand.

A distributed architecture is proposed and implemented for generating a neural network capable of solving a particular problem without specialized knowledge of the problem domain. The only knowledge the application needs is a training set that the network …

Evaluating A Social Skills Training Protocol In A Private Setting: Outcomes And Issues, Judi Davis

UNLV Theses, Dissertations, Professional Papers, and Capstones

Society is dealing with a trend of aggressive and destructive behavior among children and adolescence. Children with social, emotional, and conduct problems are at high risk for academic failure, peer rejection, conduct disorder, school dropout, delinquency, and drug and alcohol problems (Webster-Stratton, Reid, & Stoollmiller, 2008). A high priority for the United States public health and crime prevention is the prevention of aggressive and delinquent behavior during childhood and adolescence (Taylor, Eddy, & Biglan 1999).

Social skills trainings aim to increase the performance of key social behaviors that are important for children to succeed in social situations. Solutions may be …

Bryoecology In The American Southwest: Patterns Of Biodiversity And Responses To Global Change, John Carroll Brinda

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation combines investigation of the large-scale responses of bryophyte species diversity and distribution with small-scale physiological adaptations to global change. These two areas of inquiry are linked because one way to predict plant species responses to global change is to examine their distribution across current ecological gradients produced by factors such as latitude and elevation. By examining these biogeographic patterns one can identify those species that have a narrow tolerance and therefore are most sensitive to change. Selected bryophytes might then be used as indicator species in long-term monitoring programs. Where historical data exist, these can be used to …

Spectroscopic Methods Of Process Monitoring For Safeguards Of Used Nuclear Fuel Separations, Jamie Lee Warburton

UNLV Theses, Dissertations, Professional Papers, and Capstones

To support the demonstration of a more proliferation-resistant nuclear fuel processing plant, techniques and instrumentation to allow the real-time, online determination of special nuclear material concentrations in-process must be developed. An ideal materials accountability technique for proliferation resistance should provide nondestructive, realtime, on-line information of metal and ligand concentrations in separations streams without perturbing the process. UV-Visible spectroscopy can be adapted for this precise purpose in solvent extraction-based separations.

The primary goal of this project is to understand fundamental URanium EXtraction (UREX) and Plutonium-URanium EXtraction (PUREX) reprocessing chemistry and corresponding UV-Visible spectroscopy for application in process monitoring for safeguards. By …

The Role Of Metrical Structure In Tonal Knowledge Acquisition, Matthew Rosenthal

UNLV Theses, Dissertations, Professional Papers, and Capstones

Experienced listeners possess a working knowledge of pitch structure in Western music, such as scale, key, harmony, and tonality, which develops gradually throughout childhood. It is commonly assumed that tonal representations are acquired through exposure to the statistics of music, but few studies have investigated potential learning mechanisms directly. In Western tonal music, tonally stable pitches not only have a higher overall frequency of occurrence, but they may occur more frequently at strong than weak metrical positions, providing two potential avenues for tonal learning. Two experiments employed an artificial grammar learning paradigm to examine tonal learning mechanisms. During a familiarization …

A Diffusion Tensor Imaging Software Comparison And Between Control Subjects And Subjects With Known Anatomical Diagnosis, Michael C. Moore

UNLV Theses, Dissertations, Professional Papers, and Capstones

Diffusion weighted imaging (DWI) is a magnetic resonance imaging (MRI) method that produces in vivo images of biological tissues weighted with the local micro-structural characteristics of water diffusion. Diffusion tensor imaging (DTI), a form of DWI, is useful when a tissue, such as the neural axons of white matter in the brain, has an internal fibrous structure that allows water to diffuse more rapidly in alignment with the fibers. Changes in the water diffusion pattern indicate changes in the fiber structure which can result from damage to the fibers. Measurements of the water diffusion patterns include overall diffusivity, Apparent Diffusion …

Association Between Childhood Demographics And Blood Lead Screening---Nevada Kindergarten Health Survey 2010, Lina Zhang

UNLV Theses, Dissertations, Professional Papers, and Capstones

Lead, as a toxic substance, invades the human body, and gradually damages the organs. Oftentimes, elevated blood lead levels are not recognized until serious health issues are found. In the United States, approximately 250,000 children aged 1-5 years have elevated blood lead levels greater than 10 micrograms of lead per deciliter of blood (Centers for Disease Control and Prevention, 2004).

However, there is no effective treatment for lead poisoning. Chelation can merely decrease the blood lead levels but cannot reverse the existing damage. To prevent and control childhood lead poisoning, many studies have been conducted to investigate the sources of …

Bacterial Adherence Of Streptococcus Mutans And Lactobacillus Acidophilus On Poly-Methyl Methacrylate And Thermoplastic Polypropene Used In Orthodontic Retention, Lindsay Ann Pfepper

UNLV Theses, Dissertations, Professional Papers, and Capstones

Retention is required in the majority of orthodontic patients throughout the remainder of their life. The two primary removable appliances are known as the traditional Hawley retainer or the vacuum formed retainer. These appliances were developed to maintain the position of the dentition without sacrificing oral health. The orthodontic population is at a higher risk for caries due to plaque accumulation from poor diet, suboptimal oral hygiene and often lack of motivation. These two retainers occupy different niches and are comprised of different materials; therefore the retainers' effect on oral health could be very different. An understanding of which bacteria …