Digital Commons Network^™

Establishing A Comprehensive Framework For Sfrt Lattice Treatments: Optimization, Planning, And Clinical Evaluation, Gregory M. Gill

UNLV Theses, Dissertations, Professional Papers, and Capstones

Spatially fractionated radiation therapy (SFRT) using lattice radiotherapy (LRT) has emerged as a promising treatment technique for bulky, nonresectable tumors by delivering spatially heterogeneous dose distributions consisting of high-dose vertices embedded within lower-dose regions. Although early clinical experiences have demonstrated potential therapeutic benefit, widespread clinical implementation of LRT remains limited due to the absence of standardized treatment planning workflows, consistent optimization strategies, and clearly defined evaluation metrics for heterogeneous dose distributions. The objective of this study is to develop and evaluate a structured framework to support efficient, reproducible, and safe clinical implementation of LRT.

To address these challenges, a comprehensive …

A Modified Maximum Likelihood Estimation Algorithm For Modeling Threshold Exceedances With The Generalized Pareto Distribution, Jeffrey Harkness

UNLV Theses, Dissertations, Professional Papers, and Capstones

A modified maximum likelihood estimation (MLE) algorithm is proposed for modeling threshold exceedances with the generalized Pareto distribution (GPD). The algorithm addresses multiple issues with an approach originally published in the Journal Computational Statistics and Data Analysis (Castillo and Serra, 2015). The modified algorithm is intended to be comparatively simple to understand and implement, accurate in the handling of boundary conditions, relatively fast and reliable for most data sets, and relatively easy to transfer between computer languages by leveraging existing optimization routines.

A reproducibility study of work in recent literature published in the journal Extremes (Belzile, et al., 2023) is …

The Effect Of Dialogic Reading With An Adapted Reader On Narrative Reading Comprehension Of High School Students With Autism Spectrum Disorder, Ramella Lee

UNLV Theses, Dissertations, Professional Papers, and Capstones

Reading comprehension is essential for accessing grade-level content; however, students with autism spectrum disorder (ASD) often demonstrate narrative comprehension difficulties related to language inferencing and self-regulation (Constable, 2013; Duke & Cartwright, 2021). Dialogic reading is an evidence-based shared reading practice that uses systematic prompts and contingent consequences to strengthen verbal behavior (Whitehurst et al., 1988; IES, 2007). Despite demonstrated effectiveness with young children with ASD, experimental research on dialogic reading with secondary school-aged students, particularly those requiring adapted instructional materials, remains limited (Hudson & Test, 2011; Spooner et al., 2012). The purpose of this study was to evaluate the effects …

Prepulse Inhibition And Emotion: A Systematic Review, Jennifer U. Le

UNLV Theses, Dissertations, Professional Papers, and Capstones

Prepulse inhibition is a neurological pre-conscious sensorimotor gating mechanism by which a softer auditory sound (or prepulse) preceding a startle probe (or pulse) and subsequently reduce the magnitude of the startle blink reflex. Prepulse inhibition is deficient in many psychological disorders where emotion is a central component; however, emotion has been scarcely examined with prepulse inhibition in human studies. The current study is a systematic review that examines three databases (APA PSYCInfo, Pub Med, and CINAHL) to examine how state and trait emotion (such as happiness, sadness, anger, disgust) is related to prepulse inhibition within human subjects. The initial search …

Exploring The Impacts Of Contextualized Learning In An Engineering-Specific Corequisite Precalculus Course On Student Achievement, Motivation, And Belongingness, Amy Mathis-Leonard

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study examines the design and implementation of a contextualized engineering-specific corequisite Precalculus I course and its impacts on student achievement, motivation, and sense of belonging. This study was conducted in response to decreasing national rates of mathematical readiness, the elimination of stand-alone developmental mathematics courses across multiple states and systems, and the demand for research related to effective corequisite models in mathematics coursework. The intervention created an experimental section of corequisite Precalculus I in which all the students were engineering majors who did not demonstrate readiness for a college-level precalculus course. Unit lessons incorporated engineering-specific topics and career-oriented discussions. …

Exact Solution Of Steady Seepage In An Asymmetrical Domain Underneath A Cofferdam, Tan Nguyen

UNLV Theses, Dissertations, Professional Papers, and Capstones

For decades, the evaluation of steady state seepage beneath asymmetrical cofferdams has relied on numerical methods, such as Finite Element Methods (FEM), Finite Difference Method (FDM), Finite Volume Method (FVM), Mesh Reduction Method (MRM), Meshless Method (MM), Boundary Element Method (BEM), or geometric idealizations, most notably Griffiths' vertical Method of Fragments assumption. While exact closed form solutions via Schwarz-Christoffel (SC) conformal mapping have been well established for symmetrical geometries (Banerjee and Muleshkov), the generalized asymmetrical case has historically remained an intractable mathematical frontier. The primary barrier to an exact analytical solution has been the "crowding problem," a numerical phenomenon where …

Methylation-Dependent Regulatory Pathway That Governs The Stability Of The Sox Family Proteins And Related Developmental Regulators, Keshari Gayathri Rajawasam

UNLV Theses, Dissertations, Professional Papers, and Capstones

The SRY (Sex-determining Region Y) protein is a transcription factor encoded on the Y chromosome and is the key regulator responsible for initiating male sex determination in mammals. During early embryonic development, SRY activates the genetic program that leads to testis formation by promoting the expression of downstream genes involved in male gonadal differentiation. Mutations or dysregulation of SRY can lead to disorders of sex development such as male-to-female sex conversion and hermaphroditism, highlighting its critical role in sex determination.

SRY belongs to the SOX (SRY-related HMG-box) family of transcription factors, which includes the proteins SOX1, SOX2 and SOX3. These …

Fast Radio Bursts And Long Period Radio Transients: Radiation Mechanisms And Propagation Effects, Yuanhong Qu

UNLV Theses, Dissertations, Professional Papers, and Capstones

Fast Radio Bursts (FRBs) are bright radio bursts with the highest brightness temperatures in the radio sky. In this thesis, we investigate the trigger mechanisms, radiation mechanisms, and propagation effects of FRBs. Two general classes of coherent radiation mechanisms are considered in two categories: pulsar-like models invoking emission originating within the magnetar magnetosphere, and GRB-like models, which attribute the emission to relativistic magnetized shocks occurring far away from the central engine. We use the general observed properties (polarization features and spectra bandwidths) of repeating FRBs to constrain the physical conditions needed for these two mechanisms. We propose that crust quakes …

Who Am I As An Elementary Cs Teacher? The Identity Development And Struggles Of Elementary Teachers As Computer Science Teachers, Burak Sahin

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study investigates how elementary teachers develop and negotiate their identities as computer science (CS) teachers within the expanding presence of CS in early K–12 education. As CS is increasingly integrated into early grades, many teachers are expected to teach it without formal preparation. It positions them to simultaneously learn, teach, and construct a professional identity in an unfamiliar domain. Using an interpretive phenomenological approach, this study examines teachers’ lived experiences of identity development by drawing on identity theory (Gee, 2000) and the performance, recognition, and competence framework (Carlone & Johnson,2007) to understand how identity is shaped through practice, institutional …

Examining The Relationships Among Collaborative Teaching Practices, Self-Efficacy, And Teachers' Self-Regulation In Charter School Culture, Melissa J. Seltenreich

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation examined the relationships among collaborative teaching practices, teacher selfefficacy, and self-regulation among 226 in-service K–12 teachers in Southern Nevada public charter schools. Teaching is a demanding profession that requires strong self-regulation (goal setting, monitoring, reflection, and adaptive strategies) and self-efficacy to sustain effective instruction, teacher well-being, and professional longevity. Collaborative teaching practices, which emphasize teamwork, shared planning, and peer support, were hypothesized to strengthen these psychological capacities within charter environments characterized by high autonomy and accountability. This research study focuses on 3 questions including demographic and situational variables that contribute to differences in teachers’ self-regulation, teachers with higher …

From Culture To Classroom: The Influence Of Professional Learning Communities On The Learning Organization And High-Cognitive Demand Instruction, Rebecca J. Tschinkel

UNLV Theses, Dissertations, Professional Papers, and Capstones

As schools face increasing pressure to prepare students for the complexities of the 21st century, the role of job-embedded professional learning has become paramount to school improvement. This study investigated the relationships among teacher perceptions of the characteristics of Professional Learning Communities (PLCs), the dimensions of the school as a Learning Organization (LO), and the frequency of high-cognitive-demand instructional practices. Grounded in Learning Organization Theory and the concept of evidence-based PLCs, this research sought to determine whether collaborative teacher structures could serve as a predictive lever for instructional rigor, regardless of school demographics, and to examine their influence on the …

Visual Interpretability Of Multimodal Tissue Perfusion Classification Using Grad-Cam And Saliency Maps, Metehan Zorluoglu

UNLV Theses, Dissertations, Professional Papers, and Capstones

Accurate identification of the tissue perfusion phase from hand images can aid doctors in decision-making with non-invasive techniques. The present study proposes a multimodal deep learning model for classifying the tissue perfusion phase using infrared, thermal, and visible spectrum images of the human hand. The proposed model consists of various preprocessing techniques such as manipulation, homography alignments, and masking. The significant contribution of this thesis is the interpretability analysis of deep learning models, achieved through the analysis of saliency maps and the Gradient-weighted Class Activation Mapping (Grad-CAM) methods. The purpose of this method is to find out how the convolutional …

Digital Literacy And Language Proficiency As Factors Of Accessible Digital Training In The Hospitality Industry: Employee Perspectives Of Training And Working In A Diverse Industry, Gillian Bowden

UNLV Theses, Dissertations, Professional Papers, and Capstones

This explanatory sequential mixed methods study explored how digital literacy and language proficiency impact employees’ access to and engagement with digital training, as well as how these experiences influence their perceptions of training and the organization. In the quantitative phase, survey data were collected from hourly employees at a large foodservice corporation (n=67). Four constructs were assessed: digital literacy, language proficiency, accessibility, and engagement. Results indicated strong, statistically significant relationships with higher levels of digital literacy and language proficiency associated with greater accessibility and increased engagement with digital training materials. The large effect sizes suggest these competencies play a meaningful …

A Technical Analysis Of Ground Stone From The Group Iv Neighborhood At Palenque, Mexico, Alexandra Castillo Espinoza

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ground stone tools (manos and metates used to grind food) are among the most recovered yet least studied artifacts in Classic Period Maya archaeology. Their consistent association with women's domestic labor has contributed to their analytical neglect, producing a gap in what is known about daily food production, household organization, and the lives of the people most responsible for both. This thesis addresses that gap through a technical analysis of 211 ground stone artifacts recovered from the Group IV neighborhood at Palenque, Chiapas, Mexico, by the Proyecto Regional de Palenque (PREP) between 2016 and 2025. It is the first systematic …

Iterative Silver-Label Refinement For Temporal Information Extraction In Biomedical Literature, Chan Lee

UNLV Theses, Dissertations, Professional Papers, and Capstones

Temporal information extraction plays a critical role in the biomedical domain, where the ability to identify events and their temporal relationships is central to interpreting research findings. However, annotated corpora for this task remain scarce and costly to produce and the existing models developed for clinical text do not transfer well. This work bridges that gap through iterative silver-label refinement. A temporal model originally trained on news-domain data is adapted to biomedical text through cycles of automatic labeling, targeted correction, and retraining without the need for comprehensive manual annotation.

Key contributions include a practical iterative refinement methodology demonstrating that the …

From Flight To Hatching: Adult Sexual Dimorphism, Life History, And Egg-Stage Ecology Of Pseudocotalpa Giulianii, Mandylene Mountain

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Nevada endemic dune beetle Pseudocotalpa giulianii is currently known only from two dune systems in Amargosa Valley, Nevada, yet much of its life cycle occurs below the sand surface and remains poorly documented. This thesis addresses key gaps in adult-stage biology and egg-stage development that are relevant to understanding reproduction, vulnerability, and habitat requirements in this dunerestricted species.

To characterize adult sexual dimorphism and life history, I quantified morphological differences between males and females and measured sex-specific adult survival under laboratory conditions relative to the aboveground flight season. Males and females overlapped broadly in external body size, but tarsal …

Skin Of Frog And Scale Of Dragon: Nutritional Cues, Life Cycle Kinetics, And Secretome Dynamics In Batrachochytrium Dendrobatidis, Naomi C. Okada

UNLV Theses, Dissertations, Professional Papers, and Capstones

Nearly 50% of amphibian species are at risk of extinction, making them the most threatened group of vertebrates on the planet. A major driver of these declines is the pathogenic chytrid fungus Batrachochytrium dendrobatidis (Bd), which causes the fatal skin disease chytridiomycosis. Since its discovery in the late 1990s, Bd has been directly implicated in the extinction of 90 species of amphibians and the declines of hundreds more. Despite this devastating ecological impact, relatively little is known about its basic cellular biology.

Bd has a multi-stage asexual life cycle consisting of a motile and infectious zoospore, which encysts (into a …

Effect Of The Sava Syndemic On Hiv Viral Suppression Among People Living With Hiv In The United States: A Scoping Review And Meta-Analysis, Jacquelyn Rodriguez

UNLV Theses, Dissertations, Professional Papers, and Capstones

The SAVA syndemic highlights the interconnected and mutually reinforcing nature of substance use, violence victimization, and HIV/AIDS. The synergistic interaction of these conditions creates structural and behavioral barriers that disrupt the HIV care continuum and contribute to significant health inequities. Achieving a suppressed viral load is a critical clinical outcome for people living with HIV, while viral non-suppression can be an indicator of poor health, elevated transmission risk, and disease progression. Still, the association between SAVA factors and viral suppression/non-suppression outcomes within U.S. populations remains inconsistently characterized due to heterogeneous methodologies and variable inclusion of high-risk groups. This mixed-methods study …

At The Crossroads Of Traditional And Nuclear Forensics: Decontaminating Radiologically Contaminated Dna Evidence Using Magnetic Beads, Rin Nyx Ruby

UNLV Theses, Dissertations, Professional Papers, and Capstones

Known for its impressive discriminatory power, deoxyribonucleic acid (DNA) fingerprinting stands as the “gold standard” of forensic investigation. However, complications arise when such evidence is contaminated with radioactive material. Though biological samples exposed to ionizing radiation can still yield comprehensive DNA profiles, most forensic laboratories lack the facilities which meet the safety and security requirements necessary for handling radioactive material. While nuclear facilities can decontaminate samples prior to forensic analysis, conventional methods for radiological decontamination – such as mechanical cleaning and chemical washes – may degrade the quality of the forensic evidence. The purpose of this study is to evaluate …

2d And 3d Insights Into The Formation And Emplacement Of Martian Meteorites, Sierra Rhaye Ramsey

UNLV Theses, Dissertations, Professional Papers, and Capstones

Martian meteorites are the only samples currently available from Mars, making their study critical for understanding martian igneous processes. Despite extensive study over the last five decades, the formation (e.g., mantle sources, crystallization pressures), emplacement (e.g., intrusive versus extrusive), and shock histories of these rocks remain uncertain due to their innate lack of geologic context and limited petrologic tools calibrated for martian conditions. This dissertation analyzes a large suite of 22 igneous martian meteorites using complementary 2D and 3D analytical methods to better constrain the magmatic, emplacement, and shock processes responsible for their formation and ejection from Mars.

Chapters 2 …

Evaluating An Educational Intervention On Screen-Time And Behavior Change: A Pilot Study, Kayla L. Sweeney

UNLV Theses, Dissertations, Professional Papers, and Capstones

Background: Excessive screen time among adolescents has been associated with negative health outcomes, including sleep disturbances, anxiety, and depression. Despite growing awareness, many parents lack sufficient understanding of these risks and their impact on adolescent well-being. This project evaluated whether a brief educational intervention improved parents’ knowledge of the health effects of excessive screen time. Methods: A pre-and post-survey design was used to assess changes in parents’ understanding following an educational video intervention. The educational intervention consisted of evidence-based content highlighting the impact of screen time on mental health and sleep. The survey measured knowledge, beliefs, behavioral intentions, and strategies …

An Ex Post Facto Study: The Social Validity Of Two Evidence-Based Instructional Practices, K. Ryan Wennerlind

UNLV Theses, Dissertations, Professional Papers, and Capstones

For over 15 years, the opportunity for individuals with intellectual disabilities to continue education in inclusive postsecondary education programs has steadily risen (Baker et. al, 2018). Poor employment trends for these individuals has motivated institutions to provide more educational opportunities by increasing the number of such programs. Education is consistently linked to greater employment opportunities and the potential for greater earnings as more education is achieved (BLS, 2023). Research attests this connection by studying individuals’ experiences in education after high school. In addition to greater employment opportunities, those individuals receiving postsecondary education services are also earning wages at a higher …

Navigating The Unknown: Understanding The Impact Of Mentorship For First-Generation Students In Stem, Shanika Roshanie Wickramarachchi

UNLV Theses, Dissertations, Professional Papers, and Capstones

First-generation students often encounter systemic barriers and inequities in academic pursuits related to science, technology, engineering, and math (STEM). Many institutions implement mentoring programs to mitigate these challenges; however, the effectiveness of STEM mentoring relationships for first-generation college students has been underexplored in the empirical literature. The current study centers the voices of first-generation college students to explore how mentors and institutions can better support their success through STEM mentoring relationships. In addition, this study examines how mentors’ generational status informs how they approach mentoring relationships with first-generation mentees. Participants included mentors and first-generation mentees in STEM research mentoring relationships …

Shelters In Motion, Erin Nicole Vallido Trasmano

Hospitality Design Graduate Student Capstones

Shelters in Motion is a modular temporary shelter system for festival and outdoor events that replaces disposable tents with reusable, durable design. Overall reducing environmental impact while significantly improving comfort and user experience.

The Origins Of Chondrite Families, Isabelle M. Perron

UNLV Theses, Dissertations, Professional Papers, and Capstones

Chondrites, a type of primitive asteroid, are thought to have formed from dust and gas early in the life of our Solar System. These chondrites have remained unchanged since their formation, avoiding being melted or differentiated like other rocky bodies have. Due to this unique characteristic, chondrites can give us useful insight into how asteroids, planetesimals, and even the terrestrial planets formed. In order to study chondrites and their formation, I used code developed by Li et al. (2020), which utilizes thermodynamic code GRAINS (Petaev 2009), to see what conditions the chondrites may have originated from. GRAINS uses a variety …

Principal Perceptions Of Autonomy And Its Relationship To Job Satisfaction, Kay H. Barlow

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study examined the relationship between principal perceived job autonomy and principal job satisfaction through the lens of Self-Determination Theory. Specifically, it addresses the research question: What is the relationship between principal autonomy and principal job satisfaction? Using bivariate correlations and Ordinary Least Squares regression analyses, the study investigated overall and domain-specific autonomy, including human resources, instructional leadership, facilities, and finance, and their association with overall and subscale measures of job satisfaction including salary, promotion, supervision, benefits, contingent rewards, working conditions, coworkers, the work itself, and communication. Findings indicate a positive and statistically significant correlation between perceived job autonomy and …

Preservation Of Sedimentary Rubidium Isotopic Signatures In Subduction Zones: Insights From The Schistes Lustrés Hp-Uhp Metasediments, Western Alps, Mary Clarich

UNLV Theses, Dissertations, Professional Papers, and Capstones

When oceanic plates bend and sink into the mantle at subduction zones, they carry sediments from the surface down into the mantle. The recycled sediments contain elements, that are depleted in the mantle, thereby influencing the composition of the mantle wedge and the formation of arc magmas, which are the building blocks of juvenile continental crust. However, it remains poorly constrained how much these elements, particularly fluid-mobile elements such as rubidium (Rb), are lost into fluids during metamorphic dehydration, and how much is transported to sub-arc depths where arc magmas are generated. Rubidium in subducting sediments is mainly hosted in …

Harnessing Backcasting To Identify Drivers Of Critical Warming At Hoover Dam Using Hydrodynamic And Machine Learning Models, Eunice Ledres

UNLV Theses, Dissertations, Professional Papers, and Capstones

Elevated water temperatures can pose a significant threat to dam infrastructure, potentially damaging turbines, overheating internal components, and forcing generator shutdowns. This study uses a backcasting framework to evaluate how future scenarios may result in elevated water temperatures. Backcasting defines undesirable outcomes and works backward to identify the conditions that lead to them. The developed backcasting framework integrates 3D physics-based simulations with a Long-Short Term Memory (LSTM)surrogate model and SHapely Additive exPlanations (SHAP) interpretation. The combination captures temporal water temperature dynamics and quantifies the contributions of different drivers to elevated water temperature releases. As proof of concept, these methods are …

Constructing A Laser Stabilization System For Frequency Metrology, Stephanie Letourneau

UNLV Theses, Dissertations, Professional Papers, and Capstones

Frequency metrology and quantum control, which uses light as a tool for measurement and manipulation, relies on spectrally narrow, stable lasers. Often thought of as being perfectly monochromatic and coherent, in reality, the free-running instantaneous linewidth of lasers can be on the order of hundreds of kHz in the millisecond time-frame and drift on the order of tens of MHz over hours. To correct for these instabilities in real-time, a variety of laser stabilization methods have been implemented, including the Pound-Drever-Hall (PDH) method, saturation absorption spectroscopy (SAS), and dichroic atomic vapor laser locking (DAVLL). All of these methods rely on …

Thermal Physiological Ecology Of The Relict Leopard Frog At Hot And Cold Springs, Robert P. Pelletier Iii

UNLV Theses, Dissertations, Professional Papers, and Capstones

The relict leopard frog (Rana onca) once ranged across drainages in southern Nevada, northwestern Arizona, and southwestern Utah. Following a decline, the species only persisted in a few geothermally influenced hot springs, which led to the perspective that hot springs were high-quality habitat. Rana onca has been under intensive, multiagency management and the species has been translocated to establish additional populations, including at cold-water sites. Three research studies are presented into the thermal physiological ecology of R. onca with the aim of informing conservation strategy. The research was focused at a thermally influenced hot spring and a cold-water spring to …