Physical Sciences and Mathematics Commons^™

Play-Based Assessment Of The Cardinal Principle, Allyssa Sonnefeld Leavitt

Theses and Dissertations

Gelman and Gallistel (1986) determined five counting principles that are essential for successful counting, including the cardinal principle where children understand that the last number counted represents the quantity of a set of objects. The traditional How many? task and the Give-n task are the most common tasks that have been used to assess whether children understand the cardinal principle. However, many researchers claim that these tasks either overestimate or underestimate children's understanding of the cardinal principle. Some researchers (Baroody & Pellegrino, 2023) suggest that embedding the traditional How many? task in a game may improve its validity. In this …

The Mechanics And Consequences Of The Löwenheim-Skolem And Compactness Theorems, Adam Murphy

Honors Program Theses and Projects

The compactness theorem for first-order logic says that for a set of first-order sen-tences to be satisfiable, it’s enough for every finite subset to be satisfiable. We’ll see how the compactness theorem arises from two methods of model construction: first by ultraproducts, and second by Henkin’s method of constructing models from constant symbols. We’ll explore several representative applications of compactness, such as how it can be used to demonstrate that a property is not expressible, establishing limitations on first-order expressibility. The Löwenheim-Skolem theorem says that if an infinite set Γ of first-order sentences has an infinite model, then for all …

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 …

Ankimedbench: Evaluating Hierarchical Medical Knowledge In Language Model Embeddings, Neel Patel

UNLV Theses, Dissertations, Professional Papers, and Capstones

Despite achieving over 90% accuracy on medical benchmarks, recent studies show physicians cannot effectively leverage language models to improve clinical reasoning. Current benchmarks test isolated factual recall, but clinical practice requires hierarchical navigation through diagnostic categories—starting broad and narrowing systematically from chest pain to cardiovascular pathology to myocardial infarction to specific STEMI types. Existing evaluations cannot measure whether models preserve this taxonomic structure essential for clinical reasoning.

We introduce AnkiMedBench, built from 16,512 medical flashcards used by students preparing for licensing exams. Cards are organized across six hierarchy levels spanning 16 broad medical specialties to 672 specific diseases and conditions. …

Re: Approval Letter For The Revised Draft Final Annual Operations And Maintenance (O&M) Report: Butte Treatment Lagoon (Btl) System - 2023 (Dated October 29, 2025), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Stability Analysis Of Thermohaline Convection With A Time-Varying Shear Flow Using The Lyapunov Method, Kalin Kochnev

Honors Scholar Theses

This work applies the Lyapunov method to identify instabilities and compute the growth rate of a linear time-varying system. The linear system studied describes cold fresh water on top of hot salty water with a periodically time-varying background shear flow. A time-dependent weighting matrix is employed to construct a Lyapunov function candidate. The resulting linear matrix inequalities are discretized in time using the forward Euler method. As the number of temporal discretization points increases, the growth rate predicted by the Lyapunov method or Floquet theory, used for comparison, will converge to the same value obtained from numerical simulations. Furthermore, the …

Analysis Of Leakage In Nearshore Pipelines Using Fitness For Service Method To Ensure Mechanical Integrity Based On Api-579 Level 3, Elriandri Elriandri, Dedi Priadi

Journal of Materials Exploration and Findings

The Fitness for Service (FFS) analysis is performed as a quantitative assessment to evaluate the integrity condition of a pipeline. Essentially, FFS assessment helps determine whether equipment components can operate safely despite existing deficiencies. This evaluation is carried out using the Finite Element Method (FEM). In the case of an underwater pipeline that experiences leak due to anchor pull at the flange connection, it undergoes plastic deformation and is lifted approximately 1 meter. As a mitigation step, inspection and repairs have been carried out by the company. Subsequently, modeling is performed to reconstruct the deformation process of the pipeline. Then, …

An Analysis Of Student Performance In Elementary Linear Algebra At Brigham Young University, Adrienne Irene Christensen

Theses and Dissertations

This study investigates different factors that influence performance in the Elementary Linear Algebra (ELA) course taught at Brigham Young University. These factors include student characteristics such as true freshman status and college enrollment, and content-specific factors such as how performance on essential topics affects overall performance in the course. To analyze the various research questions posed in the study, I used robust linear mixed effects models with random effects controlling for the hierarchical structure of the data. The statistically significant results from these models indicate that (i) true freshmen perform better than other students on exams and in the ELA …

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, …

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 …

Ultrafast Dynamics Of Two-Dimensional Electron Systems, Randy Michael Sterbentz

UNLV Theses, Dissertations, Professional Papers, and Capstones

On-chip terahertz time-domain spectroscopy (THz-TDS) is a technique useful for measuring the ultrafast electrodynamics of two-dimensional (2D) electronic systems. Charge carrier collisions occur on the sub-picosecond time scale, and strongly correlated electron interactions (such as superconductivity) typically have energies on the order of milli-electron-volts. These phenomena fall within the terahertz bandwidth, which has historically been difficult to access. Commercial electronics operate with transistors capable of switching rates of around 100 GHz, while small band gap semiconductors (like InGaAs) can detect light down to 0.75 eV (180 THz). When combined with the difficulty of measuring 2D layered materials, with lateral sizes …

Shallow Groundwater Extraction Strategies In The Las Vegas Valley, Nevada, Teryl Stacey

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Las Vegas Valley faces severe water scarcity due to Nevada’s limited Colorado River allocation and an arid climate. Population growth and prolonged drought have intensified these constraints, necessitating alternative resource strategies. This project evaluated a strategy to make use of brackish, shallow groundwater (from the top 30 feet below ground surface) located in the central and east-central parts of the valley. Its objective was to extract lower quality shallow groundwater for use as an alternative to fresh water currently being used for some applications that require little to no treatment. Dust suppression is among the most promising of such …

Mapping Climatic And Environmental Determinants Of Parasitic Helminth Prevalence In Southeast Asia, Angelica Avisado

UNLV Theses, Dissertations, Professional Papers, and Capstones

Climate change is reshaping environmental conditions across Southeast Asia (SEA) through rising temperatures, altered precipitation patterns, and increased droughts. These changes alter transmission dynamics of neglected tropical diseases (NTDs) by shifting spatial distribution, increasing larval development rates, faster pathogen growth development, and increasing transmission rates. NTDs are a group of preventable and treatable infections that disproportionately affect more than 1 billion people globally, specifically in tropical and subtropical regions. A subgroup of NTDs, parasitic helminth infections (PHIs) - particularly schistosomiasis, soil-transmitted helminths, and lymphatic filariasis remains a public health concern in the Southeast Asian region. PHIs and their ecological responses …

Towards Spatial Inversion Of Aerial Gamma-Ray Survey Data For Measurement Of Naturally Occurring Radioactivity, Daniel A. Haber

UNLV Theses, Dissertations, Professional Papers, and Capstones

Aerial gamma-ray surveying (AGRS) is used in geologic and environmental contexts to provide data on the surface spatial distribution of naturally occurring radioactive material (NORM) or other gamma-ray-emitting isotopes. The standard data reduction workflow for AGRS data involves a process whereby pointwise gamma-ray spectral data are denoised, corrected for numerous sources of background radiation and aircraft height, and are finally converted to physical values by empirical conversion factors. The reduced pointwise data are then typically spatially interpolated to form a continuous surface map.

This dissertation introduces and explores a novel spatial inversion method for reduced AGRS data that considers aircraft …

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, …

Reconstructing Central American Hydroclimate Changes Across Time From Isotopic Signatures In Modern And Paleo-Rainfall Records, Giuseppe Lucia

UNLV Theses, Dissertations, Professional Papers, and Capstones

Tropical monsoon rainfall is a key component of Earth’s climate system and supports the livelihood and economy of billions of people. Yet, projections of future monsoons remain highly uncertain, particularly in regions with distinct physiography and complex land-ocean-atmosphere interactions like Central America, where long and continuous high-resolution paleoclimate data to test climate model simulations are still limited. This series of studies aims to reconstruct monsoon dynamics and underlying forcing controls in Central America on multiple timescales by the analysis and integration of stable isotope data in modern and paleo-rainfall records from Guatemala.

In Chapter 2, I present a daily-resolution, two-year-long …

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 …

Integrating Post-Quantum Cryptography Into A Cdn-Style Pki: Tls And Quic Performance Across Pqc Suites, Katrina Mary Parsom

UNLV Theses, Dissertations, Professional Papers, and Capstones

Post-quantum cryptography (PQC) adds larger certificates and extra workload to the Transport Layer Security (TLS) handshake. In order to analyze the effect of that change on content delivery, a controlled testbed with conditions replicating a Content Delivery Network (CDN) is used. The system uses a standard X.509 certificate chain over TLS 1.3. It compares RSA with classical key exchange, RSA with hybrid key encapsulation mechanism (KEM), and Module Lattice-based Digital Signature Algorithm (ML-DSA) with hybrid KEM. The test harness generates and provides certificates and establishes TLS parameters. The test harness also supports mixed web workloads and records key metrics, including …

A Comparison Of Airborne Tree Pollen In The Las Vegas Valley From 2017 – 2021, Asma Tahir

UNLV Theses, Dissertations, Professional Papers, and Capstones

Airborne pollen are a predominant cause of asthma, allergic disease, and respiratory infections. The strong allergenic potential of tree pollen is of a public health concern. Several allergenic trees grow in the Mojave Desert, but not all are native to the region. Concentrations of airborne tree pollen are affected by atmospheric, environmental, ecological, and geospatial factors. Previous research has reported high tree pollen concentrations in the Las Vegas Valley, but long-term comparison studies are lacking. This study measured and compared tree pollen concentrations from five different collection stations in Las Vegas. Pollen samples collected from January 1, 2017, to December …

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, …

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 …

Patterns Of Llm Weaponization: A Comparative Analysis Of Exploitation Incidents Across Commercial Ai Systems, George Antoniou

Faculty and Staff Publications & Presentations

This comparative study examines patterns of Large Language Model (LLM) weaponization through systematic analysis of four major exploitation incidents spanning 2023-2025. While existing research focuses on isolated incidents or theoretical vulnerabilities, this study provides the first comprehensive comparative framework analyzing exploitation patterns across state-sponsored cyber-espionage (Anthropic Claude incident), academic security research (GPT-4 autonomous privilege escalation), social engineering platforms (SpearBot phishing framework), and underground criminal commoditization (WormGPT/FraudGPT ecosystem). Through comparative analysis across eight dimensions—adversary sophistication, target selection, exploitation techniques, autonomy levels, detection evasion, attribution challenges, defensive gaps, and capability democratization—this research identifies critical cross-case patterns informing defensive prioritization. Findings reveal three …

Testing For Dice Control At Craps, Stewart N. Ethier

UNLV Gaming Research & Review Journal

Dice control involves “setting” the dice and then throwing them carefully, in the hope of influencing the outcomes and gaining an advantage at craps. How does one test for this ability? To specify the alternative hypothesis, we need a statistical model of dice control. Two have been suggested in the gambling literature, namely the Smith–Scott model and the Wong–Shackleford model. Both models are parameterized by θ ∈ [0, 1], which measures the shooter’s level of control. We propose and compare four test statistics: (a) the sample proportion of 7s; (b) the sample proportion of pass-line wins; (c) the sample mean …

Gpu-Accelerated Effective Hamiltonian Calculator, Abhishek Chakraborty, Taylor L. Patti, Brucek Khailany, Andrew N. Jordan, Anima Anandkumar

Mathematics, Physics, and Computer Science Faculty Articles and Research

Effective Hamiltonian calculations for large quantum systems can be both analytically intractable and numerically expensive using standard techniques. In this manuscript, we present numerical techniques inspired by Nonperturbative Analytical Diagonalization (NPAD) and the Magnus expansion for the efficient calculation of effective Hamiltonians. While these tools are appropriate for a wide array of applications, we here demonstrate their utility for models that can be realized in circuit-QED settings. Our numerical techniques are available as an opensource Python package, qCHeff, which is available on GitHub (https://github.com/ NVlabs/qCHeff) and PyPI (https://pypi.org/ project/qcheff/). We use the CuPy library for GPU-acceleration …

There Is No Obstruction To A Euclidean Proof For The Fourth Postulate, José Gil-Férez, Piotr Błaszczyk, M. Andrew Moshier, Alberto Naibo, Jean-Michel Salanskis

Mathematics, Physics, and Computer Science Faculty Articles and Research

In Gil-Férez et al. (2025), we presented a proof of Postulate 4 using purely Euclidean techniques, against which Blåsjö (2025) raised several objections. In this note, we offer linguistic, textual, historical, and mathematical evidence that demonstrate that all these objections are baseless.

Fault Structure, Deformation Mechanisms, And Why Fault Zones Matter To Society, Elizabeth S. Petrie, David A. Ferrill, Kelly K. Bradbury, James P. Evans

Geosciences Faculty Publications

Faults are widespread geologic structures that form in sediment and all rock types, occur in all tectonic regimes, and can be a blessing or a curse to society. Faults and fault zones act as conduits for underground movement of water and as plumbing systems for aquifers and springs essential for human habitation in many semi-arid and arid regions worldwide. Faults also provide pathways for natural oil and gas migration and high-permeability zones in hydrocarbon reservoirs, as well as barriers contributing to trapping and reservoir compartmentalization. By enhancing permeability in many geothermal energy systems, faults can be essential for fluid circulation …

The Effect Of Phosphate Fertilizer And Organic Matter On Phosphorus Status, Ph, And Cabbage Yield In Andisols, Mahfud Arifin, Emma Trinurani Sofyan, Anni Yuniarti, Rina Devnita, Sastrika Anindita

Jurnal Kultivasi

Andisols are characterized by high phosphorus (P) retention, which often limits P availability for crops. This study aimed to analyze the independent and interactive effects of P fertilizer and organic matter (i.e. manure and rice straw compost) on P retention, total P, available P, P uptake, soil pH, and cabbage yield. This research was conducted in pot experiments in plastic house, applying P fertilizer (0, 90, 180, 270 kg ha-1) and organic matter (20 kg ha-1 of chicken, sheep, cow manures and rice straw compost) on Andisols planted with cabbage. The experiment used a factorial randomized design. The results showed …

A Comprehensive Study Of Clique Graphs And Clique Regular Graphs, Connor Phillips

Senior Honors Projects, 2020-current

If Γ is a graph for which every edge is in exactly one clique of order ω, then one can form a new graph with vertex set equal to these cliques.  This is a generalization of the line graph of Γ.  We discover many general results and classifications related to these clique graphs that will be useful to researchers studying graphs with this property. In particular, we find bounds on the spectrum of Γ (with exact results when Γ is k-regular) and some complete classifications when Γ is strongly regular. We apply our results to derive novel information about the …

Contemporary Martian Geomorphic Processes And The Suitability Characterization Of Terrestrial Analogues, Daniel Paul Mason

Earth and Planetary Sciences ETDs

Both historical and contemporary evidence for geomorphic activity on the surface of Mars is apparent. This evidence is showcased by features including a) well-preserved deltaic remnants in an otherwise cold and arid environment, present along the western flank of Jezero Crater, and b) the seasonal appearance of candidate recurring slope lineae throughout Martian equatorial, lower, and mid-latitudes as seen within both the Eos Chasma region and on the walls of Raga, Lohse, Rauna, and Tivat Craters. In this dissertation, I elucidate the role that geomorphic processes, whether aqueous or dry, have played in shaping both the ancient and contemporary Martian …

Assessment Of Fish Community Dynamics, Movement, And Morphology In Relation To Stream Barriers In The Upper Illinois Bayou Watershed, Risa Mccollough

ATU Theses and Dissertations 2021 - Present

Intermittent streams are increasingly recognized as vital components of river networks by supporting dynamic fish communities shaped by variable hydrology and habitat connectivity. They are becoming increasingly vulnerable to fragmentation by anthropogenic activities, namely road crossings, dams, and climate shifts that intensify seasonal drying. In response, I conducted two studies in the Illinois Bayou watershed in Arkansas to assess the effects of fragmentation on fish community dynamics and morphology in intermittent streams.

In the first study, I examined temporal fish community dynamics across two barriers: a natural waterfall in Dare Creek and a low-water crossing in Dry Creek. Simultaneously, I …