Digital Commons Network^™

The Reliability Of Parafoveal Cone Density Measurements, Benjamin S. Liu, Sergey Tarima, Alexis D. Visotcky, Alex Pechauer, Robert F. Cooper, Leah Landsem, Melissa A. Wilk, Pooja Godara, Vikram Makhijani, Yusufu N. Sulai, Najia Syed, Galen Yasumura, Anupam K. Garg, Mark E. Pennesi, Brandon J. Lujan, Alfredo Dubra, Jacque L. Duncan, Joseph Carroll

Biomedical Engineering Faculty Research and Publications

Background Adaptive optics scanning light ophthalmoscopy (AOSLO) enables direct visualisation of the cone mosaic, with metrics such as cone density and cell spacing used to assess the integrity or health of the mosaic. Here we examined the interobserver and inter-instrument reliability of cone density measurements.

Methods For the interobserver reliability study, 30 subjects with no vision-limiting pathology were imaged. Three image sequences were acquired at a single parafoveal location and aligned to ensure that the three images were from the same retinal location. Ten observers used a semiautomated algorithm to identify the cones in each image, and this was repeated …

Pathway Pioneer: Heterogeneous Server Architecture For Scientific Visualization And Pathway Search In Metabolic Network Using Informed Search, Vipul Kantilal Oswal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

PathwayPioneer is a website to visualize the biological models. The complex metabolic models are hard to perceive when read through text format. It is even more difficult to understand the flow of network and different subsystem or pathways. PathwayPioneer organizes different subsystems into simple graphical representation. We simplify the complex network based on subsystem and compartment. Users can do computation (flux balance analysis) through the user interface and perceive the changed model visually. Our system is one of its kind to handle large model files with quick response time.

Biologists are often interested in knowing different alternative pathways targeting a …

An Exploration Of Object And Scientific Skills-Based Strategies For Teaching Archaeology In A Museum Setting, Candice L. Cravins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A pilot study conducted at the Utah State University Museum of Anthropology explores the most engaging strategies for teaching archaeology to children in a museum setting. During a week-long summer workshop event in June 2013, two styles or modes of teaching archaeology were contrasted and evaluated: object-based teaching and scientific-skills based teaching. The teaching styles are evaluated based on third and fourth grade students' level of excitement and engagement with various archaeology activities - which activities are the most interesting and engaging to children while they are in the museum? The first mode of teaching archaeology focuses on object-based learning. …

Multi-Scale Modeling Of Microbial Defection In The Presence Of Antibiotics, Darshan Dilip Nahar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Limited environmental resources push life into competition. In terms of microbes, we assume that the only goal is to grow and competition means to grow faster than the peers. Organisms tend to adapt to their environmental conditions and improve their efficiency in using the common resources to grow faster. While different organisms compete they engage into various social behaviors like cooperation to work together towards a common goal, e.g., production of public goods that benefits the entire population. Hence a part of the resources at hand is dedicated to participate in cooperative activities if the cost-to-benefit ratio is less than …

Effects Of Contaminated St. Lucie River Saltwater Sediments On An Amphipod (Ampelisca Abdita) And A Hard-Shell Clam (Mercenaria Mercenaria), Tham C. Hoang, Gary M. Rand

School of Environmental Sustainability: Faculty Publications and Other Works

The St. Lucie estuary (SLE) ecosystem in South Florida has been shown to be contaminated with metals and pesticides. Our earlier studies also showed that aquatic organisms, especially benthic species in the SLE ecosystem, might be potentially at high risk from copper (Cu) exposure. The objectives of this study were to conduct studies with separate groups of organisms exposed to seven field-collected sediment samples from the St. Lucie River according to standard procedures to evaluate toxicity and tissue concentrations of Cu and zinc (Zn). Short term and longer term whole sediment acute toxicity studies were performed with Ampelisca abdita and …

Problems In The Theory Of Convergence Spaces, Daniel R. Patten

Dissertations - ALL

We investigate several problems in the theory of convergence spaces: generalization of Kolmogorov separation from topological spaces to convergence spaces, representation of reflexive digraphs as convergence spaces, construction of differential calculi on convergence spaces, mereology on convergence spaces, and construction of a universal homogeneous pretopological space. First, we generalize Kolmogorov separation from topological spaces to convergence spaces; we then study properties of Kolmogorov spaces. Second, we develop a theory of reflexive digraphs as convergence spaces, which we then specialize to Cayley graphs. Third, we conservatively extend the concept of differential from the spaces of classical analysis to arbitrary convergence spaces; …

Development And Application Of Explicitly Correlated Wave Function Based Methods For The Investigation Of Optical Properties Of Semiconductor Nanomaterials, Jennifer Mary Elward

Dissertations - ALL

Semiconductor nanoparticles, or quantum dots (QDs), are well known to have very unique optical and electronic properties. These properties can be controlled and tailored as a function of several influential factors, including but not limited to the particle size and shape, effect of composition and heterojunction as well as the effect of ligand on the particle surface. This customizable nature leads to extensive experimental and theoretical research on the capabilities of these quantum dots for many application purposes.

However, in order to be able to understand and thus further the development of these materials, one must first understand the fundamental …

Transforming Management Of Tropical Coastal Seas To Cope With Challenges Of The 21st Century, Peter F. Sale, Tundi Agardy, Cameron H. Ainsworth, Blake E. Feist, Johann D. Bell, Patrick Christie, Ove Hoegh-Guldberg, Peter J. Mumby, David A. Feary, Megan I. Saunders, Tim M. Daw, Simon J. Foale, Phillip S. Levin, Kenyon C. Lindeman, Kai Lorenzen, Robert S. Pomeroy, Edward H. Allison, R. H. Bradbury, Jennifer Corrin, Alasdair J. Edwards, David O. Obura, Yvonne J. Sadovy De Mitcheson, Melita A. Samoilys, Charles R.C. Sheppard

Marine Science Faculty Publications

Over 1.3 billion people live on tropical coasts, primarily in developing countries. Many depend on adjacent coastal seas for food, and livelihoods. We show how trends in demography and in several local and global anthropogenic stressors are progressively degrading capacity of coastal waters to sustain these people. Far more effective approaches to environmental management are needed if the loss in provision of ecosystem goods and services is to be stemmed. We propose expanded use of marine spatial planning as a framework for more effective, pragmatic management based on ocean zones to accommodate conflicting uses. This would force the holistic, regional-scale …

Real‐Time Oceanographic Data: From Safety To Science, Steven D. Meyers, Jeffrey Scudder, Mark E. Luther

Marine Science Faculty Publications

Coastal areas such as bays and estuaries host 30%–50% of the global human population and shipping ports that handle 80% of world trade. These areas are increasingly vulnerable to chemical and biological contamination and to storm surge in the short term and to sea level rise in the long term.

The Percussionist Bodybuilder: Optimizing Performance Through Exercise And Nutrition, Anthony Joseph Merlino

UNLV Theses, Dissertations, Professional Papers, and Capstones

Do preventive therapies have the potential to help avoid common injuries among percussionists? This document investigates physiological therapy and nutrition in relation to percussion performance. My interest in this subject matter is derived from my personal experiences with injuries related to the performance of percussion. Although I have studied and played percussion professionally for more than a decade, I was unaware of certain methods of rehabilitation that were available to me prior to my injuries. As I learned about the rehabilitation process through first hand experience, I discovered that my injuries were very common among percussionists. This raised the question: …

The Effect Of Acute Lps-Induced Immune Activation And Brain Insulin Signaling Disruption In A Diabetic Model Of Alzheimer's Disease, Andrew Scott Murtishaw

UNLV Theses, Dissertations, Professional Papers, and Capstones

Alzheimer's disease (AD) is a neurodegenerative disorder marked by progressive cognitive impairments and pathological hallmarks that include amyloid plaques, neurofibrillary tangles, and neuronal loss. Several well-known mutations exist that lead to early-onset familial AD (fAD). However, these cases only account for a small percentage of total AD cases. The vast majority of AD cases are sporadic in origin (sAD) and are less clearly influenced by a single mutation but rather some combination of genetic and environmental risk.

The etiology of sAD remains unclear but numerous risk factors have been identified that increase the chance of developing AD. Among these risk …

Implicit Theories Of Intelligence And Learning A Novel Mathematics Task, Nathan Oehme Rudig

UNLV Theses, Dissertations, Professional Papers, and Capstones

The social-cognitive model of motivation states that students adopt a theory of the nature of intelligence that guides their goals in academia and their responses to academic setbacks. Students who believe intelligence is an unchanging entity within them are more likely to adopt goals to display high ability, hide low ability, and respond helplessly to failed schoolwork. Conversely, a student who believes intelligence is a measure of effort and persistence will be motivated to gather knowledge and acquire new skills. The current study investigated the role theories of intelligence play in the field of mathematics understanding. In two experiments, participants …

Metabolic Remodeling Of White Adipose Tissue In Obesity, Timothy D. Cummins, Candice R. Holden, Brian E. Sansbury, Andrew A. Gibb, Jasmit Shah, Nagma Zafar, Yunan Tang, Jason Hellmann, Shesh N. Rai, Matthew Spite

Brain and Mind Institute

Adipose tissue metabolism is a critical regulator of adiposity and whole body energy expenditure; however, metabolic changes that occur in white adipose tissue (WAT) with obesity remain unclear. The purpose of this study was to understand the metabolic and bioenergetic changes occurring in WAT with obesity. Wild-type (C57BL/6J) mice fed a high-fat diet (HFD) showed significant increases in whole body adiposity, had significantly lower V̇o2, V̇co2, and respiratory exchange ratios, and demonstrated worsened glucose and insulin tolerance compared with low-fat-fed mice. Metabolomic analysis of WAT showed marked changes in lipid, amino acid, carbohydrate, nucleotide, and energy metabolism. Tissue levels of …

Construction Of 3d Biomimetic Tissue Niches For Directing Pancreatic Lineage Differentiation Of Human Embryonic Stem Cells, Weiwei Wang

Graduate Theses and Dissertations

The potential of human embryonic stem cells (hESCs) to differentiate into insulin producing beta cells offers great hope for cell-based therapy for diabetes treatment. However, in vitro pancreatic differentiation of hESCs remains challenging. In the past decade, most protocols for differentiating pancreatic cells have been focused on the use of signaling molecule cocktails on 2D substrates. Studies on embryonic development biology strongly suggest that extracellular matrix (ECM) plays a critical role on hESCs behavior. In this work, we first established a 3D collagen scaffold culture system for hESCs differentiating into definitive endoderm (DE), which is the first and most important …

Biology, Ecology, And Control Of Doveweed (Murdannia Nudiflora [L.] Brenan), Jeffrey Atkinson

All Dissertations

Doveweed (Murdannia nudiflora [L.] Brenan) is a summer annual in the Southeastern United States with an expanding geographic range. The light green color and texture of doveweed is problematic for turfgrass managers as it contrasts with the color and texture of desirable turfgrasses. Limited research is available concerning the biology, ecology, and herbicide control options for doveweed. Therefore, experiments were conducted to improve the understanding of how environmental conditions effect doveweed germination, how cultural practices and environmental resource availability effect doveweed growth and development, to identify pre- and postemergence herbicides with efficacy for doveweed control, and to improve the understanding …

Encouraging The Appropriate Use Of High Beam Headlamps: An Application Of The Theory Of Planned Behavior, Stephanie Whetsel Borzendowski

All Dissertations

Drivers typically underuse their high beam headlamps at night even under ideal conditions (i.e., no leading, following, or oncoming vehicles). One explanation for this is a lack of knowledge regarding both the magnitude of visibility problems at night and the benefits that high beams provide. The purpose of the present study was to design and evaluate an educational intervention based on the Theory of Planned Behavior (TPB) that targeted a more appropriate reliance on high beams. The results of Study 1 indicated that attitudes toward high beams best predicted intentions to use high beams. This information informed the design of …

Passivation And Functionalization Of Conjugated Polymer Nanoparticles With Head Group Modified Phospholipids And Proteins, Prakash Kandel

All Dissertations

Conjugated polymer nanoparticles (CPNs) possess important characteristics such as high fluorescence brightness, reasonable photostability, and non-toxicity. These properties allow the use of CPNs in fluorescence based cellular and biological applications including cellular labeling, imaging, biosensing, and single particle tracking. To realize the broad applications of CPNs, it is required that CPNs possess functionality to conjugate a recognition moiety and maintain colloidal stability in biological media. In the following Dissertation, we have prepared functionalized CPNs by surface passivation with head group- functionalized poly (ethylene glycol) lipids and proteins. We studied the colloidal stability of CPNs in biological media and investigated their …

Evaluation Of A Mycorrhizal-Like Fungus, Piriformospora Indica, On Floriculture Crops, Allison Justice

All Dissertations

Piriformospora indica is a fungal endophyte, often called an arbuscular mycorrhizal-like fungus, that has been shown to provide benefits to plant symbionts by increasing nutrient uptake, biomass production, flower number, and disease resistance in a wide range of plant hosts. Research was carried out to investigate the ability of P. indica to improve plant production in floriculture crops. The first objective was to determine the optimal environmental conditions for growing P. indica in pure culture. Environmental conditions were optimized to produce the maximum chlamydospores for inoculum preparation (Chapter 1). These findings were used in the remaining chapters to prepare inocula …

Mechanisms And Reversal Of Elastin Specific Medial Arterial Calcification, Yang Lei

All Dissertations

There are two distinctive types of vascular calcification: atherosclerotic intimal calcification (AIC) and elastin specific medial arterial calcification (MAC). AIC occurs in the context of atherosclerosis, associated with lipids, macrophages, and vascular smooth muscle cells; whereas, MAC can exist independently of atherosclerosis and is associated with elastin and vascular smooth muscle cells. The work presented here focuses on the mechanisms and reversal of MAC. MAC, termed as Monckeberg's sclerosis, is a type of vascular calcification disease mostly occurs as linear deposits along elastic lamellae. Vascular calcification, including medial calcification, is a strong predictor of cardiovascular morbidity and mortality. Currently the …

The Effects Of Amine Structure, Chloramine Species And Oxidation Strategies On The Formation Of N-Nitrosodimethylamine, Meric Selbes

All Dissertations

To comply with the increasingly stringent disinfection by-product (DBP) regulations in the United States, many water treatment plants have been switching from chlorination to chloramination in the last decade. Although chloramination reduces the formation of regulated DBPs such as trihalomethanes and haloacetic acids, it causes the formation of nitrosamines. Nitrosamines are a class of compounds that are probable human carcinogens, mutagens and teratogens at concentrations as low as 0.2 ng/L. In particular, N-nitrosodimethylamine (NDMA) is the most frequently detected nitrosamine in distribution systems in the United States. Although, nitrosamines are currently not regulated by the USEPA, they have been recently …

Electrostatic And Electrical Transport Analysis Of Nanomaterials And Numerical Methods Development, Hua Li

All Dissertations

The nanotechnology today is continuously boosting the application of nanostructured materials in the development and innovation of electronic devices, such as Nano &ndash Electromechanical Systems (NEMS), electrical transistors, thermoelectric devices, and solar cells. Due to the size miniaturization, quantum mechanical effects play important roles in the performance of such devices. To correctly capture the quantum mechanical effects and understand how these effects influence the electrostatic and electrical transport properties of nanomaterials, efficient and accurate computational models are highly desirable. Currently, the commonly used model for electrostatic analysis of nanoscale devices is based on self &ndash consistent solution of the effective …

Processing-Structure-Property Relationships Of Meat And Bone Meal Derived Bioplastics, Sam Lukubira

All Dissertations

Sustainability concerns arising from over-use of fossil-derived materials have prompted renewed interest in developing and use of products from renewable biomass. Agricultural materials like soy, starches, cellulose esters and co-products like lignin, soybean meal, feather meal, blood meal and others are being investigated for bioplastic applications. Unlike fossil-based plastics, most of these materials are biodegradable and obtained from renewable precursors, hence sustainable.

Zinc Oxide Nanostructures For Flexible And Transparent Electronics, Do Yeob Kim

All Dissertations

As a multifunctional material, ZnO possesses remarkable and unique properties and has attracted much research interest for use in a variety of applications. Especially, it has been regarded as a leading material for flexible and transparent electronics, which is a promising emerging technology in electronics. This dissertation studies doping behavior of Ga in ZnO for transparent electrode applications and presents new approaches to ZnO nanostructures for next-generation flexible and transparent electronics. These approaches include developing techniques that enable multiple stacked ZnO nanoflowers and thermal treatment processes at high temperature.

Transparent conductive oxides have been extensively studied for the use as …

Motivational Factors Contributing To The Choice Of Agriculturally Related Careers, Lacey J. Sims

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study examined the motivational factors of college students who have chosen to study in an agriculturally related field. A descriptive research design using an online questionnaire was used for this study to determine factors which influenced career choice. Likert scale items were used to determine how motivating certain factors were for respondents in influencing their decision to study in an agriculturally related field. The Likert items were divided into five constructs: family influence, self-motivation, experience, use of skills, and career opportunities. Items within the five constructs were further analyzed to discover the top five motivational factors identified in each …

Vying For Relevancy In Stockholm: American Environmental Nongovernmental Organizations And The 1972 Un Conference On The Human Environment, Andrew Brown

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis examines the roles, ideologies, strategies, and behavior of American environmental nongovernmental organizations (ENGOs) during the 1972 United Nations Conference on the Human Environment. This conference was the first major international conference to address environmental issues. The Stockholm Conference was a meeting for delegates representing national governments to dictate the direction of international environmental regulation. The conference focused on the participation of nations but ENGOs found venues through which to participate in the discussion on the human environment. In this thesis, I argue that even though the official conference limited the participation of ENGOs, these groups functioned as informal …

Changes In Body Condition From Prepartum To Postpartum On Health And Reproduction In Dairy Cattle, Keli Ann Akers

Graduate Theses, Dissertations, and Problem Reports (ETD)

The aim of this study were to body condition score, 72 Holstein-Friesian dairy cows at prepartum, compare lean, moderate, and over-conditioned categories, and relate any changes associated with the various time points with reproductive success by measuring body condition score, hematocrit, total white blood cell (WBC) differential, haptoglobin (Hp) concentrations, milk yield and monitoring health status. The body condition score changed significantly with time with the greatest unit loss being in the over-conditioned cattle from d -30 to d 35 postpartum. The BCS losses for each category did not have a significant effect on reproductive success at any time. Health …

Faster Evolutionary Multi-Objective Optimization Via Gale, The Geometric Active Learner, Joseph Krall

Graduate Theses, Dissertations, and Problem Reports (ETD)

Goal optimization has long been a topic of great interest in computer science. The literature contains many thousands of papers that discuss methods for the search of optimal solutions to complex problems. In the case of multi-objective optimization, such a search yields iteratively improved approximations to the Pareto frontier, i.e. the set of best solutions contained along a trade-off curve of competing objectives.;To approximate the Pareto frontier, one method that is ubiquitous throughout the field of optimization is stochastic search. Stochastic search engines explore solution spaces by randomly mutating candidate guesses to generate new solutions. This mutation policy is employed …

The Evaluation Of Emotion Regulation In Caregivers Referred To A Parent-Training Program, Nancy M. Wallace

Graduate Theses, Dissertations, and Problem Reports (ETD)

In recent years, emotion regulation has become a topic of particular interest to both clinicians and researchers and has been shown to play a significant role in a variety of behavioral and psychological difficulties in both adults and children (Gratz & Tull, in press). However, parents of children referred for parent training may experience significant difficulty regulating their emotions as they attempt to cope with and control their children's misbehavior. The present study explored the role of caregiver emotion regulation in parent training by attempting to understand if (1) parents and children who are referred for parent training have difficulty …

Inorganic Nanoparticle Nucleation On Polymer Matrices, Adrian John Kosteleski

Graduate Theses, Dissertations, and Problem Reports (ETD)

The introduction of inorganic nanoparticles into organic materials enhances both the mechanical and chemical properties of the material. Metallic nanoparticles, like silver and gold, have been introduced into polymers for use as antimicrobial coatings or dielectric materials, respectively. The challenge in creating these materials currently is the difficulty to homogeneously disperse the particles throughout the polymer matrix. The uneven dispersion of nanoparticles can lead to less than optimal quality and undesired properties. By creating a polymer nanocomposite material with well-controlled size inorganic materials that are evenly dispersed throughout the polymer matrix; we can improve the materials performance and properties. The …

An Automated Framework For Problem Report Triage In Large-Scale Open Source Problem Repositories, Sean K. Banerjee

Graduate Theses, Dissertations, and Problem Reports (ETD)

Issue tracking systems play a critical role in the management and maintenance of software. Developers and users are allowed to submit reports pertaining to observed problems. A human triager must read through each newly submitted report, and determine if it describes an unreported issue (Primary) or an existing issue (Duplicate). If the quality of the report is deemed to be poor (Incomplete), describing an issue with a different software (Invalid), irreproducible (Worksforme), or beyond the scope of the project (Wontfix) it is annotated with the appropriate label. If the report is deemed to describe a new problem, it is assigned …