Digital Commons Network^™

Achieving More Accurate And Interpretable Fraud Detection With Double Machine Learning, Jeremy Andrew Berry

Theses and Dissertations

Fraud detection remains a critical challenge across industries such as insurance, healthcare, finance, and government. Global losses from fraud and financial crime are estimated in the trillions annually, including billions in healthcare and insurance fraud alone. While effective for prediction, traditional machine learning methods often lack causal interpretability and struggle to adapt to evolving fraud tactics. This dissertation investigates the application of Double Machine Learning (DML), an emerging causal inference technique, to enhance both the accuracy and interpretability of fraud analytics. The research compares DML against established causal inference approaches, leveraging a meta-learning framework to evaluate model performance on accuracy, …

Applied Research For Corn Production In Indiana, 2023, Daniel Quinn

Purdue University Press Books

The 2023 edition of Applied Research for Corn Production in Indiana offers accessible, research-based tips for farmers who want to improve corn production practices by using applied field-research trials. Daniel Quinn and the Purdue University Corn Agronomy team reveal practical ways to boost yields, reduce costs, and improve sustainability on the farm. Their findings are derived from applied research trials across the state and relate to important topics such as planting practices, fertilizer use, crop nutrition, cover crops, and new technologies. Applied Research for Corn Production in Indiana distills complex research into clear insights and supplies corn producers with effective …

The Effects Of Educational Materials On Knowledge And Attitudes Toward Psilocybin, Lindsey Elise Wade

Master's Theses

Depression is one of the most prevalent and burdensome mental health conditions worldwide, affecting millions and contributing to over 700,000 deaths by suicide annually. Nearly half of patients with major depressive disorder fail to respond adequately to standard antidepressant treatments such as selective serotonin reuptake inhibitors (SSRIs). Psilocybin-assisted therapy (PAT) has emerged as a promising alternative for treatment-resistant depression (TRD), yet public understanding of this therapy remains limited. The present study examined whether a brief psychoeducational intervention could affect knowledge and attitudes toward PAT among members of the general public in the United States. Participants were randomly assigned to read …

Suicidal Intentions Among Divorced Women In Wasit Province, Khitam Abbas Fadhel, Hassan Aii Ai-Sayed

Alustath Journal for Human and Social Sciences

The current research aims to: Identifying Suicidal Intentions Among Divorced Women Marriage is viewed as a social institution that includes a set of norms regulating the relationship between spouses. The strength of this structure relies on solid foundations such as proper selection and compatibility in social aspects. Marriage imposes on spouses a set of mutual obligations and rights ensuring the continuity of marital life and enabling the family to fulfill its basic functions Despite the psychological, health and social significance marriage, offers to individuals and society, the phenomenon of divorce has been increasingly prevalent in recent times across various communities …

Low-Dimensional Signatures Of Neuronal Activity Associated With Long-Term Operant Conditioning In Aplysia, Sara Vanaki, Nicholas O Gonzalez, Curtis L Neveu, Yuto Momohara, Behnaam Aazhang, John H Byrne

Faculty, Staff and Student Publications

Operant conditioning is a form of learning in which a behavior is reinforced by reward. Operant conditioning has multiple temporal domains, ranging from short-term, lasting a few minutes, to long-term, persisting for at least 24 h. The extent to which short- and long-term operant conditioning memories rely on shared or separate neural mechanisms is poorly understood. Voltage-sensitive dye (VSD) imaging has been used previously to record the activity of a large number of neurons simultaneously in the buccal ganglion to measure changes in neuronal activity during short-term operant conditioning. We examined neuronal activity using VSD 24 h after operant conditioning …

Enviromental Dna (Edna) Tools For Invasive Mosquitofish (Gambusia Affinis) Surveillance At The Shoshone Pupfish (Cyprinidon Nevadensis Shoshone) Refugium, Yusuf Olamilekan Umar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Spring-fed aquatic ecosystems of the North American Southwest and U.S. Great Basin hosts a plethora of endemic fish species due to the effects of hydrologic fragmentation that resulted from Pleistocene aridification. Threats to endemic fishes worldwide include human intentional or unintentional release of exotic species into their habitats. Early detection of invasive species, while corrective actions are still possible, is critical for management, yet traditional survey methods are often disruptive to sensitive ecosystems, costly, and limited in sensitivity. The recent development of environmental DNA (eDNA) approaches offers powerful alternatives for invasive species monitoring in aquatic systems. In this study, a …

Targeting Kinesin Family Member 20a Sensitizes Stem-Like Triple-Negative Breast Cancer Cells To Standard Chemotherapy, Yayoi Adachi, Weilong Chen, Cheng Zhang, Tao Wang, Nina Gildor, Rachel Shi, Haoyong Fu, Masashi Takeda, Qian Liang, Fangzhou Zhao, Hongyi Liu, Jun Fang, Jin Zhou, Hongwei Yao, Lianxin Hu, Shina Li, Lei Guo, Lin Xu, Ling Xie, Xian Chen, Chengheng Liao, Qing Zhang

Faculty, Staff and Student Publications

Triple-negative breast cancer (TNBC), being both aggressive and highly lethal, poses a major clinical challenge in terms of treatment. Its heterogeneity and lack of hormone receptors or HER2 expression further restrict the availability of targeted therapy. Breast cancer stem cells (BCSCs), known to fuel TNBC malignancy, are now being exploited as a vulnerability for TNBC treatment. Here, we dissected the transcriptome of BCSCs and identified kinesin family member 20A (KIF20A) as a key regulator of BCSC survival and TNBC tumorigenesis. Genetic depletion or pharmacological inhibition of KIF20A impairs BCSC viability and tumor initiation and development in vitro and in vivo. …

Protocol For Isolation Of Lipid Droplets And Mitochondria From Acute Myeloid Leukemia Cells For Lipidomic Analysis, Ran Zhao, Liang Zhang, Shuxin Dong, Kazuharu Kamachi, Saurabh Kumar Gupta, Hiroki Akiyama, Jalen Nguyen, G Lavender Hackman, Michael Andreeff, Alessia Lodi, Jo Ishizawa

Faculty, Staff and Student Publications

Lipid droplets (LDs) are dynamic organelles critical for lipid and energy homeostasis. LD dysregulation is implicated in various diseases, including acute myeloid leukemia (AML), which exhibits aberrant lipid metabolism and chemoresistance. Here, we describe an effective protocol for the co-isolation of LDs and mitochondria from lipid-deficient cell types, e.g., AML cells. We detail procedures for the isolation, quality verification, and results from mass spectrometry-based lipidomic analysis. This protocol enables the functional study of organellar lipidomic regulation in AML.

Elucidating The Role Of Pbaf Chromatin Remodeling Subunit Arid2 In B Cell Development, Rachel Paolini

Arts & Sciences Graduate Student Theses and Dissertations

B cells are key components of the adaptive immune system that mediate humoral immunity through the production of antigen-specific antibodies. The generation of functional B cells involves multiple stages of differentiation across distinct anatomical niches, requiring precise regulation of microenvironmental signals and intrinsic transcriptional networks. SWI/SNF chromatin remodeling complexes have emerged as key regulators of B cell lineage commitment by modulating the accessibility of transcriptional programs required for differentiation and maturation. However, the specific roles of individual SWI/SNF subunits and distinct complexes within early B cell differentiation remain poorly understood. In this thesis, I investigated the function of Arid2, an …

Meta-Analysis Of The Spatial Distribution And Composition Of Plastic Macro-Debris In Indonesia, Max R. Kelly, Muhammad Reza Cordova, Susan Jobling, Richard C. Thompson

School of Biological and Marine Sciences

Plastic pollution is recognised as a global environmental problem with Indonesia identified as a major contributing source. However, a comprehensive understanding of pollution patterns remains hindered by fragmented data and methodological inconsistencies across studies. This study synthesises data from 44 peer-reviewed publications, spanning 68 field locations and 328 individual study sites across 19 provinces, to map the spatial distribution and composition of plastic macro-debris in Indonesia. We identified plastic bags, plastic food packaging, and plastic bottles as the three most prevalent item types, occurring as top three ranked items in 65 %, 63 %, and 40 % of field locations, …

Beyond Additive Risk: Longitudinal Associations Between Discrimination And Positive Affect Development Among Adolescents With Single And Multiple Marginalized Identities, Vanni Jefferson V. Arcaina

UNLV Theses, Dissertations, Professional Papers, and Capstones

Adolescents with marginalized identities often face chronic exposure to discrimination, a social stressor linked to a range of negative mental health outcomes. While much of the existing literature focuses on internalizing symptoms, fewer studies have explored how discrimination may disrupt the development of positive affect (POA), which is a core dimension of emotional well-being linked to resilience, identity formation, and long-term health. The present study examined how overall, race/ethnicity-based, and sexual minority (SM)-based discrimination affects longitudinal patterns of POA among adolescents with single or multiple marginalized identities. Drawing on four waves of data from the Adolescent Brain Cognitive Development Study, …

Automated Spectrum Analysis And Radionuclide Identification For Robot-Based Gamma Probes, Kennedy Ochieng Mengoh Alila

UNLV Theses, Dissertations, Professional Papers, and Capstones

Gamma spectroscopy is a technique used for the detection and identification of nuclear materials. Gamma-ray emission by radio nuclides is detected using scintillation detectors or semiconductor detectors such as NaI and CZT. Robot-based gamma probes enable radiation measurements in large areas and hard-to-reach cluttered hazardous environments, which significantly reduces radiation risks to personnel. The robotic probes require automated on-board gamma spectrum analysis and capabilities with platforms (unmanned aerial vehicles and unmanned ground vehicle systems) which use Robot Operating System (ROS). The aim of this thesis was to develop a method of an automated spectral analysis and isotope identification for robot-based …

Acute And Chronic Effects Of Neuroinflammation On Hippocampus And Anterior Cingulate Cortex Network Dynamics, Lauren A. Crew

UNLV Theses, Dissertations, Professional Papers, and Capstones

Neuroinflammation has emerged as a critical modulator of cognitive function and neural circuit dynamics, yet the distinct contributions of acute and chronic neuroinflammation to brain function remain poorly defined. This dissertation examines how inflammation independently alters large-scale neural activity and behavior, focusing on interactions between the hippocampus (HPC) and anterior cingulate cortex (ACC), regions essential for memory and executive processes. Using in vivo electrophysiological techniques in a rodent model, this study compares the effects of short-term (acute) and prolonged (chronic) neuroinflammatory states, induced via Poly I:C, on neural oscillations, regional coherence, and spatial coding. Findings reveal that even transient inflammation …

Mitochondrial Complex Ii Orchestrates Divergent Effects In Cd4+ And Cd8+ T Cells, Keisuke Seike, Shih-Chun A Chu, Yuichi Sumii, Takashi Ikeda, Meng-Chih Wu, Laure Maneix, Dongchang Zhao, Yaping Sun, Marcin Cieslik, Pavan Reddy

Faculty, Staff and Students Publications

Mitochondrial metabolism orchestrates T cell functions, yet the role of specific mitochondrial components in distinct T cell subsets remains poorly understood. Here, we explored the role of mitochondrial complex II (MC II), the only complex from the electron transport chain (ETC) that plays a role in both ETC and metabolism, in regulating T cell functions. Surprisingly, MC II exerts divergent effects on CD4+ and CD8+ T cell activation and function. Using T cell-specific MC II subunit, succinate dehydrogenase A-deficient (SDHA-deficient) mice, we integrated single-cell RNA-seq and metabolic profiling, with in vitro and in vivo T cell functional assays to illuminate …

Loss Of Mfap5 And Its Effect On Skin Homeostasis And Wound Healing, Chen Han, Heidi Yuan, Timothy J Koh, Lin Chen, Robert P Mecham, Luisa A Dipietro

2020-Current year OA Pubs

MFAP5, also known as microfibrillar-associated glycoprotein-2 (MAGP2), may influence parameters of skin wound healing related to scar formation. To further elucidate its role in skin wound healing, we assessed skin wound repair in Mfap5

Facts And Hopes Of Chimeric Antigen Receptor-Redirected Nk T Cells, Amy N Courtney, Xin Zhou, Gengwen Tian, Ying Wang, Leonid S Metelitsa, Gianpietro Dotti

Faculty, Staff and Students Publications

Chimeric antigen receptor (CAR)-engineered invariant NK T cells (CAR-NKT) are a novel cell platform for cancer immunotherapy. Unlike conventional T cells, NKTs are characterized by innate antitumor properties, minimal alloreactivity, and a unique ability to modulate the tumor microenvironment. This article provides a comprehensive overview of preclinical and early clinical studies evaluating CAR-NKTs in both autologous and allogeneic clinical settings. We discuss the contributions of CAR signaling domains, cytokine coexpression, and other functional measures that correlate with CAR-NKT persistence, function, and metabolic fitness. We also discuss the critical role of immunocompetent animal models in elucidating the interactions of CAR-NKTs with …

A Long Non-Coding Rna Leat1 Mediates The Hormone Responsiveness Of Efnb2 During Male Urogenital Development, Deidre Mattiske, Pascal Bernard, Paul E Gradie, Richard R Behringer, Paul A Overbeek, Rachel J O'Neill, Tiffany Phillips, Melanie Stewart, Neil Youngson, Gerard Tarulli, Andrew J Pask

Faculty, Staff and Students Publications

The novel long non-coding RNA (lncRNA) Leat1 is extraordinarily conserved in both its location (syntenic with EfnB2, an essential gene in anogenital patterning) and sequence. Here we show that Leat1 is upregulated following the production of testosterone from the developing testis in mice and interacts with EfnB2, positively regulating its expression. Leat1 expression is suppressed by estrogen, which in turn suppresses the expression of EfnB2. Moreover, the loss of Leat1 leads to reduced EfnB2, resulting in a severe hypospadias phenotype. The human LEAT1 gene is also co-expressed with EFNB2 in the developing human penis, suggesting a conserved function for this …

Transdiagnostic Links Of Reward Processing In Obsessive-Compulsive Disorder And Depression, Kevin M Wagner, Matti Cervin, Jessica S C Cheng, Jasmine Arriaga, Vanessa Zavala Cruz, Dayan Berrones, Josselyn S Muñoz, Renee M Frederick, Jacey L Anderberg, Belinda E Núñez Bracho, Victor R Adorno, Leonardo F Fontenelle, Andrew D Wiese, Latin American Trans-Ancestry Initiative For Ocd Genomics (Latino), Brazilian Obsessive-Compulsive Spectrum Disorder Working Group (Gttoc), James J Crowley, Eric A Storch

Faculty, Staff and Students Publications

Objectives: Transdiagnostic models aim to uncover shared mechanisms across mental disorders. Reward responsiveness (the ability to experience pleasure from rewarding stimuli) is a plausible, yet underexplored, transdiagnostic mechanism linking obsessive-compulsive disorder (OCD) and depression. This study used network analysis to (1) examine how key reward responsiveness domains are interlinked in individuals with OCD and (2) explore how each domain is uniquely associated with OCD and depression.

Methods: A total of 1345 individuals with a history of OCD symptoms (ages 18-88, 71 % women) from Latino communities in the United States (including Puerto Rico) and nine Latin American countries completed validated …

Methylation-Based Signature To Distinguish Indolent And Aggressive Prostate Cancer, Muheng Liao, Jace Webster, Amy Ly, Emily Rozycki, Christopher A Maher

2020-Current year OA Pubs

Prostate cancer management faces significant challenges in distinguishing indolent from aggressive disease, particularly since most patients are intermediate-risk and therefore hinders the ability to recommend standardized treatment recommendations. Moreover, current prognostic tools including Gleason scoring and tumor staging demonstrate limited accuracy for predicting disease progression and tumor recurrence. DNA methylation serves as a stable epigenetic modification that directly regulates gene expression, making it an ideal biomarker for cancer prognosis. Therefore, this study leveraged whole-genome enzymatic methylation sequencing on 120 patients to develop a novel prognostic signature for aggressive prostate cancer progression. We analyzed 20,849 differentially methylated regions (DMRs) and employed …

Functional And Microbial Consequences Of Experimental Evolution Under Starvation In Drosophila Melanogaster, Kristal Marie Aguilar-Conger

UNLV Theses, Dissertations, Professional Papers, and Capstones

Previous studies in the Gibbs lab have shown that starvation resistant Drosophila melanogaster flies have increased lipid content, lower metabolic rates, and poor physiological health. Historically, many evolutionary studies end at the phenotypic level, leaving the genomic basis largely unresolved. Using Evolve and Resequence (E&R) study, we can map genome-wide allele-frequency trajectories under selection, linking phenotypic shifts to their genomic underpinnings. This study utilized the E&R approach to identify enriched biological processes and pathways underlying starvation adaptation in Drosophila melanogaster. Five replicate restart populations (RS A–E) selected for starvation resistance, along with a control (RC), were resequenced at Generations 1, …

Computational Study Of Cavitation In An Inducer Pump, Jaylen Leonard

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cavitation is ubiquitous in liquid-handling turbomachines. Cavitation bubbles form when the local pressure drops below a fluid’s vapor pressure, and their subsequent collapse causes implosions that generate shockwaves and microjets. These effects lead to fluid instability and structural damage to the blades and casing in turbomachines. This thesis investigates this cavitation phenomenon in turbomachines using Computational Fluid Dynamics (CFD). The cavitation model built in ANSYS Fluent® is first validated in a venturi tube model and then applied to an inducer pump. The geometry of the pump is derived from the Space Shuttle Main Engine (SSME) Low Pressure Oxidizer Pump (LPOP) …

Geometric And Proximity Based Substrate Targeting By Cullin-Ring Ligases, Jerry Li

UNLV Theses, Dissertations, Professional Papers, and Capstones

Homeostasis, the process of maintaining stable biochemical and biophysical conditions, is a fundamental facet of cellular viability. Biochemical homeostasis is critical to support the biological functions that sustain living organisms. Protein ubiquitylation is one of the primary cellular pathways that regulate protein homeostasis and turnover. Ubiquitylation is initiated through the conjugation of a small globular protein known as ubiquitin, onto a given substrate. There exists a myriad of cellular fates that ubiquitylated proteins may undergo, but the most widely studied pathway is protein degradation, whereby a ubiquitylated protein substrate is shunted to a large macromolecular protease known as the proteasome, …

Gaming: An Untapped Resource For Women In Computer Science Careers?, Claudia Quynh Luu

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research focused on women who identify as gamers (i.e., an individual who regularly plays video games) with the goal of better understanding how being a gamer might help or hinder women’s interest in computer science careers. In particular, I examined the connection between interest in computer science careers, gaming, sexual harassment experiences, coping strategies, and allyship for women in gaming using a mixed-methods approach. The sample (N = 166) included women identifying as previous or current gamers. Participants were recruited from a psychology participant pool and gaming communities on Discord. We conducted a series of analyses to examine whether …

Quantifying Biocrust Evaporation In Arid Lands By Combining Thermal Imaging And Lysimeter Measurements, Rebekah C. Magness

UNLV Theses, Dissertations, Professional Papers, and Capstones

Biological soil crusts (biocrusts) are miniature ecosystems of living organisms incorporated within the soil matrix and established in the topmost millimeters of the soil surface. Biocrust plays a critical role in the hydrologic processes in arid lands, yet the extent to which it increases or decreases evaporation remains unclear. To gain a better understanding of the impact of biocrust on evaporation compared to bare soil, I studied a cyanobacteria-dominated biocrust patch surrounded by bare soil atop a lysimeter in the Mojave Desert near Las Vegas, Nevada. Using high-resolution thermal imaging, and the known latent heat flux from the lysimeter, I …

Characterization Of The Electronic Structure Of Metal–Organic Framework Mil-125 And Its Derivatives Using Soft X-Ray Spectroscopies, Jennifer Alexia Napoles

UNLV Theses, Dissertations, Professional Papers, and Capstones

Metal–organic frameworks (MOFs) are highly porous, three-dimensional networks composed of coordinated metal clusters and organic ligand subunits. While tens of thousands of MOFs have been synthesized, the Ti(IV)-based MOF MIL-125 has garnered scientific interest due to the observed changes to its optical and photocatalytic properties upon chemical modification. For example, upon UV irradiation in the presence of an alcohol, MIL-125 undergoes a photochromic color change to a photodoped state that has been associated with the storage of charge in the form of Ti(III) sites. Another example is exemplified by the amine group functionalization of the 1,4-benzenedicarboxylate (BDC) linker of MIL-125 …

Design And Development Of Biomimetic Hydrogel Interfaces For Enhanced Bioelectrical Signal Acquisition, Daniela Nikoloska

UNLV Theses, Dissertations, Professional Papers, and Capstones

Every second, human skin processes over one million sensory signals while maintaining properties such as electrical conductivity, mechanical adaptability, and regenerative capability that surpass all synthetic materials. Contemporary bioelectronic devices prove inadequate when contacting skin surfaces due to poor adhesion and electrical contact issues that prevent effective sensing. Despite advancements in wearable and bioelectronic technologies, current devices face major drawbacks when interfacing with human skin, particularly in maintaining firm adhesion, conformability, and low-noise electrical signal acquisition.

This research focuses on the development of a biomimetic hydrogel-based interface for bioelectronic sensing. Specifically, a hybrid hydrogel system composed of polydopamine (PDA)- doped …

Deciphering The Crl Code: Novel Mechanisms Of Canonical And Non-Canonical Ubiquitylation, Nicholas Wayne Purser

UNLV Theses, Dissertations, Professional Papers, and Capstones

Protein degradation is a fundamental process required for maintaining cellular homeostasis in eukaryotic organisms. In humans, distinct cell types exhibit unique proteomic landscapes that are dynamically balanced by the continual synthesis and degradation of proteins. The timely removal of damaged, misfolded, or old proteins is essential to permit new protein synthesis and to ensure proper cellular function.

Central to this regulatory network is ubiquitylation, a highly conserved posttranslational modification system that governs protein stability and function across all eukaryotic cells. Through the covalent attachment of ubiquitin molecules to protein substrates, this system modulates a broad range of biological processes, including …

First-Principles Insights Into Binary Oxide Systems Under Extreme Pressure, Daniel Schacher

UNLV Theses, Dissertations, Professional Papers, and Capstones

Pressure is powerful tool by which one can manipulate the properties of materials. In this work we utilize pressure to explore binary oxide systems and characterize their structural and electronic properties. The observation of anomalous structural and electronic behavior in the rutile to CaCl2 phase transition in SnO2 led to the prediction that such behavior is inherent to all oxides experiencing such a phase transition sequence.[1] Here, the ultra-wide band gap semiconductor GeO2 is confirmed to exhibit anomalous behavior during the rutile to CaCl2 phase transition. A phase pure rutile GeO2 sample synthesized under high-pressure, high-temperature, conditions is probed using …

Quantum Sensing Of Magnetic And Thermal Fields Using Nitrogen-Vacancy Centers On Spoof Surface Plasmon Waveguides, Maxwell Stonham

UNLV Theses, Dissertations, Professional Papers, and Capstones

Nitrogen-vacancy (NV) centers in nanodiamonds are solid-state quantum defects capable of detecting magnetic fields and temperature at the nanoscale with high spatial resolution and optical addressability at room temperature. Their spin-dependent fluorescence enables optically detected magnetic resonance (ODMR), a technique widely used for quantum sensing. However, enhancing optical readout efficiency remains a critical challenge for scalable integration and various methods can be used to improve this.

This thesis explores a hybrid quantum sensing platform that integrates NV-based sensing with spoof surface plasmon waveguides designed to enhance optical excitation and emission efficiency through localized spoof plasmon modes supported by subwavelength corrugated …

Modeling The Mojave: A Multiphase, Mixed Methods Phenomenological Investigation Of Novice Understanding Of A Complex Ecological System, Nicole Juliana Thomas

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research explores early college science majors’ conceptions of the Mojave Desert ecosystem as a complex system. A multi-level, explanatory sequential mixed methods design was employed to study college science majors’ understanding of the Mojave Desert ecosystem to better inform science pedagogy. The first level, the quantitative phase of the study, consisted of developing a mathematical representation of twelve ecosystem variables present within the Mojave Desert. The second level, the qualitative phase of the study, consisted of phenomenological semi-structured interviews with 23 early college science majors. The findings of this research suggest that the Mojave Desert operates as a complex, …