Digital Commons Network^™

Studies On Kernels Of Simple Polygons, Jason Mark

UNLV Theses, Dissertations, Professional Papers, and Capstones

The kernel of a simple polygon is the set of points in its interior from which all points inside the polygon are visible. We formally establish that for a given convex polygon Q we can always construct a larger simple polygon with many reflex vertices such that Q is the kernel of P. We present algorithms for decomposing a strongly monotone polygon into star-polygons. This decomposition is applied for developing an efficient algorithm for placing a small number of vertical towers to cover the entire given 1.5D terrain. We also present an experimental investigation of the proposed algorithm. The implementation …

Advanced Arbitrary Lagrangian-Eulerian Finite Element Methods For Unsteady Multiphysics Problems Involving Moving Interfaces/Boundaries, Rihui Lan

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this dissertation, two kinds of arbitrary Lagrangian-Eulerian (ALE)-finite element methods (FEM) within the monolithic approach are studied for unsteady multiphysics coupling problems involving the moving interfaces/boundaries. For the classical affine-type ALE mapping that is studied in the first part of this dissertation, we develop the monolithic ALE-FEM and conduct stability and optimal convergence analyses in the energy norm for the transient Stokes/parabolic interface problem with jump coefficients, and more realistically, for the dynamic fluid-structure interaction (FSI) problems by taking the discrete ALE mapping and the discrete mesh velocity into a careful consideration of our numerical analyses and computations, where …

Numerical And Experimental Analysis Of Air-Cooled Condensers, Kaipo Kekaula

UNLV Theses, Dissertations, Professional Papers, and Capstones

The scope of this project is to numerically and experimentally dry cooling process in air-cooled condensers (ACCs) designed for concentrated solar power (CSP) applications. This effort is driven by the growing economic and political pressure to reduce water consumption during power generation due to limited water resources in the arid geographic climate of the southwestern United States. A computational approach is used in conjunction with experimental validation to gain a more complete understanding of these systems.

Traditionally research into ACCs have been largely limited to air-side heat transfer modelling as it accounts for a large portion of the total thermal …

Increasing Nurses' Knowledge Of Advance Care Planning, Jocelyn K. Allen

UNLV Theses, Dissertations, Professional Papers, and Capstones

Advance care planning (ACP) is a process that seeks to ensure patients receive medical care that is consistent with their values and preferences. The process has proven benefits for patients and their loved ones but is under-utilized in clinical practice. Nurses are capable of successfully supporting patients through ACP; however, they encounter barriers that prevent their engagement in the process. These barriers include a lack of knowledge regarding ACP, poor understanding of their role in the process, and a lack of confidence to embrace the practice.

The purpose of this DNP Project was to create an evidence-based educational intervention to …

The Impact Of Electrostatic Correlations On The Electrokinetics, Elaheh Alidoosti

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this project we are interested in electrokinetics phenomenon (i.e., study of electrical charges in a liquid matter) and focus on three families of this phenomenon, dielectrophoresis, electro-osmosis and streaming current. For the first work, at concentrated electrolytes, the ion-ion electrostatic correlations effect is considered as an important factor in electrokinetics. In this project, we compute, in theory and simulation, the dipole moment for a spherical particle (charged, dielectric) under the presence of an alternating electric field using the modified continuum Poisson-Nernst-Planck (PNP) model by Bazant et al. (Phys. Rev. Lett. 106, 2011) [25]. We investigate the dependency of the …

Motivational Predictors Of Academic Risk-Taking, Danette Dee Barber

UNLV Theses, Dissertations, Professional Papers, and Capstones

Students benefit when they are willing to engage in optimal challenges (Clifford, 1991). Engagement in challenges, however, comes with academic risks, as failure may be a result. This study investigated motivational factors, including expectancy, subjective task value, mastery goal orientation, and performance avoidance goal orientation as predictors of achievement-related outcomes, including course grade and academic risk-taking. Data were collected from 317 university students enrolled in education classes. Students were given a reading passage and asked to choose questions to answer based on the passage. Students who chose harder questions were categorized as taking more risk. Students also answered questions about …

The Influence Of G4 Dna Structures On Stationary Phase Mutagenesis In Bacillus Subtilis, Tatiana Ermi

UNLV Theses, Dissertations, Professional Papers, and Capstones

Until the late 1980’s it was widely understood that bacterial variance emerges randomly during growth. Research that followed has convincingly shown evidence for mutations arising in non-growing conditions, a phenomenon known as stationary-phase mutagenesis. In Bacillus subtilis, an elegant mutagenic mechanism has been elucidated in non-growing cells that biases mutations to transcribed regions of a subpopulation. One interesting possibility is that mutations can be further biased to hotspots within genes through alternate DNA structures known as non-B DNA. Non-B DNA have been linked to genomic instability and disease in humans, lesser is known about its role in bacteria. Here we …

A Machine Learning Approach To Predict Retention Of Computer Science Students At University Of Nevada, Las Vegas, Sudhir Deshmukh

UNLV Theses, Dissertations, Professional Papers, and Capstones

Student retention is an important measure when in determining student success. Retention refers to the first-time full-time student from previous fall term who returned to the same university for the following fall term. Decline in retention rate have adverse effect on stakeholders, parents, and students view about the institution, revenue generated from tuition cost and obtaining outside funds. In an effort to increase retention rates, universities have started analyzing the factors that correlate with students dropping out. Many universities have identified some of these factors and are working on developing intervention programs to help students to elevate their academic performance …

Toward Productivity Improvements In Programming Languages Through Behavioral Analytics, Patrick Daleiden

UNLV Theses, Dissertations, Professional Papers, and Capstones

Computer science knowledge and skills have become foundational for success in virtually every professional field. As such, productivity in programming and computer science education is of paramount economic and strategic importance for innovation, employment and economic growth. Much of the research around productivity and computer science education has centered around improving notoriously difficult compiler error messages, with a noted surge in new studies in the last decade. In developing an original research plan for this area, this dissertation begins with an examination of the Case for New Instrumentation, draw- ing inspiration from automated data mining innovations and corporate marketing techniques …

Radiology Students' Attitude Toward Learning Communication Skills: Impact Of Clinical Education, Chad Hensley

UNLV Theses, Dissertations, Professional Papers, and Capstones

The effect communication has on a patient’s healthcare experience has received increased attention in the past few decades. As a result, a larger emphasis on communication training is being incorporated into the curriculum of healthcare education programs. A student’s attitude toward learning communication skills largely determines the adoption of those skills. The radiologic technologist is a vital member of the healthcare team, yet little research has been done on their attitude toward learning communication skills. A quantitative cross-sectional study was conducted to determine the impact clinical education has on the attitude radiology students have toward learning communication skills. A total …

Discrete Vortex Modeling Of Aerodynamic Flutter Of A Flat Plate With Damped Oscillations, Emma Chao

UNLV Theses, Dissertations, Professional Papers, and Capstones

Aerodynamic flutter is the unstable oscillation of a body caused by the interaction of aerodynamic forces, structural elasticity, and inertial effects induced by vortex shedding. Current models of this phenomenon require finite element analysis and extensive computational power and processing time. The purpose of this study was to develop and validate a program that is faster and more efficient than existing approaches by using the discrete vortex method (DVM). By reducing the complexities of flutter to the shedding of vortices in an inviscid model of a two-dimensional flat plate with a torsional spring constant at its center, this phenomenon can …

Globalization: A Veto Player Perspective, Alec Brown

UNLV Theses, Dissertations, Professional Papers, and Capstones

Different countries have varying levels of globalization. Many features, such as size, play a part in determining the level of globalization in countries. I argue that globalization is influenced by veto players in systematically different ways. To understand these different relationships, globalization must be broken apart into three dimensions (political, economic, and social). Political globalization is negatively affected by veto players. Economic globalization is not affected by veto players directly but is influenced by related phenomena. Social globalization is positively affected by veto players. To test my arguments, I employ a Time Series Cross Section (TSCS) method to analyze a …

The Impact Of Culturally-Tailored Education On Knowledge And Behavior Related To Screening And Lifestyle Management Of Blood Pressure In African Immigrants, Sarah Erskine

UNLV Theses, Dissertations, Professional Papers, and Capstones

The number of African Immigrants in the United States is increasing. The prevalence of hypertension among Blacks, including African Immigrants are high. In addition to the increased susceptibility to hypertension, lack of disease awareness and unhealthy lifestyle are documented barriers to achieving adequate blood pressure control. The purpose of this project was to determine the impact of implementing a 30-minute, culturally-tailored, evidence based educational session on hypertension to promote knowledge and initiate behavior change in African Immigrants. This was a descriptive, cross-sectional study. Blood pressures were measured and survey instruments such as the Hypertension Evaluation of Lifestyle and Management scale …

Improving Type 2 Diabetes Mellitus In The Older Adult Population Utilizing Shared Medical Appointments In Primary Care Setting, Mailo Brantner

UNLV Theses, Dissertations, Professional Papers, and Capstones

The overall management of Type 2 diabetes mellitus (T2DM) and its comorbidities is complex and costly. The American Diabetes Association (ADA, 2019c) recommends the use of team-based care and self-management tools to optimize the management of T2DM. Unfortunately, there is a national shortage of endocrinologists and certified diabetes educators (Stewart, 2008) along with a primary care provider shortage (Simmons & Kapustin, 2011). Thus, it is essential to implement a care model to increase efficiency while also promoting patient knowledge and self-management of T2DM to improve health outcomes. An example of an innovative care model is the shared medical appointment (SMA), …

How Consumers Assess Multiple Cues: The Role Of Dual Processing System On Hotel Booking Decisions, Eun Joo Kim

UNLV Theses, Dissertations, Professional Papers, and Capstones

An online travel agency (OTA) is an important channel for hotels to generate new reservations. To make booking decisions, people collect and evaluate available information. Hotels try to provide effective information to persuade customers to book their hotel deals; however, not all information is manageable by the hotels. This research evaluates the effects of information on OTA websites with an approach based on the origins of the information. Depending on the origin, multiple cues can be categorized by two types, controllable and uncontrollable cues. A controllable cue is information that hotels can maintain, whereas an uncontrollable cue is not manageable …

Material Characterization Of Fiber-Reinforced Composite Materials Under Dynamic Loading Condition, Abu Iqbal

UNLV Theses, Dissertations, Professional Papers, and Capstones

Fiber reinforced composites are light materials which exhibits great strength and stiffness. They also have good dimensional stability and impact resistance. They reduce mass and improve structural performance, so the demand for fiber reinforced composite materials increases day by day in various industries such as aeronautical, automobile and military. The analysis, design, and optimization of polymer composite materials under static loading conditions are mature fields of study. Many sources are available to find material properties and predict structural response. However, composite materials are often used in extreme environments where they are subject to shock, impact, and blast loading. Efficient computational …

Shattering The Glass: Will Gen Z Bring Us Closer To Gender Equality In Us Hospitality Leadership?, Denise Holly Ramirez Molintas

UNLV Theses, Dissertations, Professional Papers, and Capstones

The continued underrepresentation of women in senior leadership positions has impaired the hospitality industry’s capacity to achieve the fifth UN Sustainable Development Goal of Gender Equality. Although the industry has initiated programs to establish gender parity, the innate gendering through traditional leadership prototypes and gender-role stratification requires investigation. Scholars have noted the limited focus on gender-aware issues in hospitality research. Further, as gender is a socialized construct, historical shifts in gender ideologies have enabled changes in gendering at the individual, interactional, and institutional dimensions of society. Grounded in gender as a social structure theory and role congruity theory, this dissertation …

Thatcherism In The Contemporary British Novel, 1978-2012, David Mowatt

UNLV Theses, Dissertations, Professional Papers, and Capstones

Thatcherism in the Contemporary British Novel, 1978-2012

This dissertation reveals a nuance to contemporary British texts that have thus far been almost homogenously categorized as contributing to a negative portrayal of the political, cultural, and social policies of the 1980s. A study of texts and criticism of the contemporary British novel highlights the disproportionate number of depictions that could be considered anti-1980s and, as a representation of that decade, in turn anti-Thatcherite. There is an apparent consensus in the damaging effects on almost all aspects of British society during the decade because of the many policies enacted by the Thatcher …

Interwoven Worlds? A Mixed Methods Study Of Student Engagement And Student Belonging Within The University Classroom When Courses Use Social Networking Sites, Christie Gardner

UNLV Theses, Dissertations, Professional Papers, and Capstones

The recent decade of technological advancements has shaped an increasingly digital experience in the everyday lives of people around the globe. One popular digital landscape for people is social networking sites (SNSs). Facebook, Twitter, Snapchat and Instagram in particular, have a large following of users from the adolescent and college-age demographic (Pew Research Center, 2019). In response, educators are integrating SNSs into classrooms to increase student engagement (Carpenter & Krutka, 2014). This raises concerns from all involved stakeholders as the social and psychological impacts of SNSs are still largely debated (Verduyn et al., 2017). This study confronts research lacunae across …

A Hybrid Experimental-Numerical Study On The Flow Topology In The Confluence Hydrodynamics Zone Of An Open Channel With Lateral Drainage Pipe Discharge, Mohammad Nazari-Sharabian

UNLV Theses, Dissertations, Professional Papers, and Capstones

To avoid disrupting the flow in flood control channels with lateral drainage pipes, or impact channel capacity, confluences are constructed at small angles (Maximum 30○). These small angles are costly to construct, since they require more real estate than greater angles.

By performing several laboratory experiments in the Fluid Dynamics Laboratory of the University of Nevada, Las Vegas (UNLV) and utilizing a numerical model (FLOW-3D), this study investigated the impact of submerged lateral drainage pipe discharges into rectangular open channels, on flow topology in the confluence hydrodynamics zone (CHZ). This was done across a range of channel widths, flow rates, …

Rapid Detection Of Toxin-Producing Cyanobacteria, Timothy Alba

UNLV Theses, Dissertations, Professional Papers, and Capstones

Lake Mead provides drinking water to millions of people in Nevada, California, and Arizona. In 2015, the Southern Nevada Water Authority detected the cyanobacteria-produced toxin microcystin in the lake for the very first time. This toxin is lethal in large doses, and in small doses it causes a myriad of serious health effects. Detecting microcystin directly is a time-consuming and expensive process that requires liquid chromatography tandem mass spectrometry or immunological analyses, which require a full day or more to process samples. In order to provide water managers with the methodology for a toxin monitoring plan, this work developed a …

Exploring The Attitudes Of Students Enrolled In A Teacher Certification Program Through A Disability Awareness Documentary Film Intervention, Eunhye Choi

UNLV Theses, Dissertations, Professional Papers, and Capstones

Negative attitudes towards individuals with disabilities can lead to a lack of opportunities in society as well as educational settings. Therefore, it is essential to promote positive attitudes to provide equal opportunities and rights to individuals with disabilities. However, there have been insufficient attempts to explore the attitudes of students enrolled in teacher certification programs. Diverse disability awareness programs have been utilized to enhance positive attitudes, and documentary films are frequently used to deliver such interventions. The current study implemented a series of documentary films as an intervention tool and examined the effects of the disability awareness documentary film intervention …

Acoustic Sonolysis Of Antibiotics In Water, Natalie Pinon

UNLV Theses, Dissertations, Professional Papers, and Capstones

Antibiotic resistance is a prominent issue in the world today. It is said by the Centers for Disease Control and Prevention that it is one of the major public health challenges we face today. Predominantly, antibiotic resistance is growing because conventional wastewater treatment processes are not able to completely break down antibiotics. As bacteria are exposed to such antibiotics, which don’t kill them due to selective pressure, they become immune and develop resistance which is a huge health concern. To prevent this from occurring, antibiotics need to be removed from hospital wastewater. Sonication is a promising technology that can be …

From Fighting Wasting To Shedding Excess: An Explanatory Sequential Mixed-Method Study Of Obesity Among People Living With Hiv In Nigeria, John Olajide Olawepo

UNLV Theses, Dissertations, Professional Papers, and Capstones

The human immunodeficiency virus (HIV) infection is a global epidemic, with initial high mortality rates since the first diagnosis over three and a half decades ago. However, the use of antiretroviral therapy (ART) has led to longer, healthier lives for many people living with HIV (PLHIV). Accordingly, aging comes with associated co-morbidities like obesity, diabetes, and cardiovascular diseases. The purpose of this mixed-methods study was to further understand the emergent phenomenon of obesity and overweight among PLHIV who are on treatment with ART, using Nigeria as a case study.

An explanatory sequential mixed-method design was used that involved the analysis …

Depressive Symptoms As A Moderator Of Diurnal Trends In Reward Seeking, Erick Albert William Rogers

UNLV Theses, Dissertations, Professional Papers, and Capstones

Anhedonia, a cardinal symptom of a major depressive episode, is the decreased motivation to seek rewards. Individuals with depressive symptoms tend to report reduced positive affect, a distal measure of reward motivation, and engage in less reward-motivated behavior (i.e., reward seeking). However, diurnal rhythms may also influence reward-seeking. Both self-reported positive affect and behavioral measures of reward-seeking increase from the morning to the afternoon and then decreased in the evening. Therefore, the aim of this study was to examine whether reward-seeking varied across time of day and whether anhedonia moderated variation. Overall, reward-seeking did not vary across time of day. …

The Significance Of Mfd And Oxidative Damage In Stationary-Phase Mutagenesis In Bacillus Subtilis, Holly Anne Martin

UNLV Theses, Dissertations, Professional Papers, and Capstones

The process of stationary-phase mutagenesis, also known as adaptative or stress-induced mutagenesis, is a phenomenon where bacterial cells accumulate mutations in non-replicative conditions. This process has mainly been studied in Escherichia coli and Bacillus subtilis; however, the underlying mechanisms found in each of these systems differ. Here, I use B.msubtilis to study previously understudied aspects of stationary-phase mutagenesis. In this dissertation, I describe work that has led to three major discoveries which are described below.

First in B. subtilis, Mfd is important for stationary-phase mutagenesis and its mutagenic function at regions of the genome that are transcriptionally upregulated has been …

Implementation Of A Training Program In The Use Of The Electronic Medical Record To Improve Performance On Quality Measures And Reduce Burnout Among Healthcare Providers, Mary Monica Nara

UNLV Theses, Dissertations, Professional Papers, and Capstones

Rapid adoption and implementation of the electronic medical record (EMR) in health care has contributed to worsening burnout among healthcare providers (HCPs), particularly primary care physicians. Other HCPs such as nurse practitioners (NPs) and physician assistants (PAs) who provide primary care have been equally affected by the increased clerical burden related to the increasing documentation requirements from payers and are at risk for burnout. Rates of burnout in NPs are currently not well known. Burnout has been linked to decreased quality of care for patients. Inadequate training and lack of skills in the use of the EMR have contributed to …

Seniors And Sexual Health: A Profile Of Sexual Behaviors And Perceptions Of Sexual Risks In Southern Nevada’S Older Adult Population, Amanda Elizabeth Morgan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Background: Older adults, 65 and older, are one of the largest growing unique population groups in the United States, comprising 15% of the population of Southern Nevada. Medical advances have allowed people to live longer, experience improved sexual health outcomes, and maintain a better quality of life. Medicare provides healthcare for most people over 65, but some people may not feel comfortable talking with their doctor or are not aware that Medicare-covered these services.

Objective: The purpose of this study is to explore the sexual behaviors of older adults age 65 years or older in Southern Nevada, examine the protective …

Abiotic, Biotic, And Bio-Enhanced Reduction Of Hexavalent Chromium, Chloroform And Co-Contaminants Using Nano-Scale Zero Valent Iron In Highly Contaminated Groundwater, Eduardo Robleto Martinez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Investigations of groundwater in a former industrial perchlorate manufacturing site have shown high contamination with perchlorate, chlorate, nitrate, hexavalent chromium (Cr (VI)), and chloroform (CF) with levels greater than 3,000, 30,000, 300, 100, and 4 mg/L, respectively. Remediation efforts using biological reduction to desired contaminant levels at this site has been challenging due to high contaminant concentrations, and high total dissolved solids (TDS). Furthermore, removal of Cr(VI) and CF in the presence of nitrate, chlorate, and perchlorate has not been examined at the contaminated site. Nano-scale Zero-Valent-Iron (NZVI) has been effective at reducing groundwater contamination both with and without bacterial …

Exploration Of The Intersection Of Social Identities Of Female Leaders In Postsecondary Education: A Phenomenological Approach, Sara Shaw

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to explore the lived experiences of female leaders currently in leadership roles in postsecondary education. This hermeneutic phenomenological study was conducted to explore intersecting identities and how the identities affected female leaders’ leadership experiences and decision-making processes. Through the theoretical framework of intersectionality, I explored the relationships among females, leadership, career decision-making, and other categorical social identities. Data gathered from semi-structured one-on-one interviews and demographic surveys with 11 female postsecondary leaders sought to understand how gender and selected social identities affect career decision-making of women in postsecondary leadership positions. The researcher identified seven themes: …