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Full-Text Articles in Physical Sciences and Mathematics

Mathematical Modeling Suggests Cooperation Of Plant-Infecting Viruses, Joshua Miller, Vitaly V. Ganusov, Tessa Burch-Smith May 2022

Mathematical Modeling Suggests Cooperation Of Plant-Infecting Viruses, Joshua Miller, Vitaly V. Ganusov, Tessa Burch-Smith

Chancellor’s Honors Program Projects

No abstract provided.


Agent-Based Dynamics Of A Spahr Opioid Model On Social Network Structures, Owen Queen, W. C. Strickland, Leigh B. Pearcy May 2022

Agent-Based Dynamics Of A Spahr Opioid Model On Social Network Structures, Owen Queen, W. C. Strickland, Leigh B. Pearcy

Chancellor’s Honors Program Projects

No abstract provided.


Vermont Global Warming Solutions Act: The Costs Of Inaction From Land Conversions, Grayson L. Younts May 2022

Vermont Global Warming Solutions Act: The Costs Of Inaction From Land Conversions, Grayson L. Younts

All Theses

The Vermont (VT) Global Warming Solutions Act (GWSA, 2020) sets greenhouse gas (GHG) emissions reduction targets as 26% below 2005 by 2025, 40% below 1990 by 2030 and 80% below 1990 by 2050 for energy-related emissions only. Vermont’s omission of GHG emissions from land conversions can result in significant costs of inaction (COI), which can hinder state’s mitigation and adaptation plans and result in a climate crisis-related risks (e.g., credit downgrade). Science-based spatio-temporal data of GHG emissions from soils as a result of land conversions can be integrated into the conceptual framework of “action” versus “inaction” to prevent GHG emissions. …


2d Materials Based Heterostructure For Quantum Tunneling: A Lithography Free Technique., Ali Alzahrani May 2022

2d Materials Based Heterostructure For Quantum Tunneling: A Lithography Free Technique., Ali Alzahrani

Electronic Theses and Dissertations

Two-dimensional electron gas (2DEG) systems have played a vital role in the development of superior electronic devices including tunnel junctions consisting of two such 2DEG systems. With the advent of the new 2D electronic material systems, it has opened a new route for 2D–2D tunneling in such extended systems. In this study, we have utilized a plasma enhanced chemical vapor deposition (PECVD) technique to directly deposit graphene (nanowalls) and h-BN on Si/SiO2 substrates to construct two-dimensional material based, vertically stacked electron tunneling devices free of expensive and cumbersome microfabrication steps. In the first study, we fabricated direct quantum tunneling …


Dataset Evaluation For Data Trading Using Expected Loss And Homomorphic Encryption, Minsung Joo May 2022

Dataset Evaluation For Data Trading Using Expected Loss And Homomorphic Encryption, Minsung Joo

Senior Honors Papers / Undergraduate Theses

Supervised machine learning suffers from the ``garbage-in garbage-out" phenomenon where the performance of a model is limited by the quality of the data. While a myriad of data is collected every second, there is no general rigorous method of evaluating the quality of a given dataset. This hinders fair pricing of data in scenarios where a buyer may look to buy data for use with machine learning. In this work, I propose using the expected loss corresponding to a dataset as a measure of its quality, relying on Bayesian methods for uncertainty quantification. Furthermore, I present a secure multi-party computation …


Driving Under The Influence Of Drugs: Status In New York City And Development Of New Analytical Tools, Kayla Marschke May 2022

Driving Under The Influence Of Drugs: Status In New York City And Development Of New Analytical Tools, Kayla Marschke

Student Theses

Driving under the influence of drugs (DUID) cases have increased in recent years. According to NHTSA, drug use among fatally injured drivers who were tested for drugs rose from 25% in 2007 to 61.4% in 2020. Knowing what drugs are used by the drivers and developing new analytical tools to detect them are essential to prevent this type of cases. The goals of this study were two-fold: 1) To investigate the prevalence of drugs and drug combinations in New York City based on data provided by the Office Chief Medical Examiner (2018-2019); 2) To develop and validate an analytical method …


Development And Novel Applications Of Halogenating Agents., Sagar Ravso Mudshinge May 2022

Development And Novel Applications Of Halogenating Agents., Sagar Ravso Mudshinge

Electronic Theses and Dissertations

Organic halides are extensively utilized as synthetic intermediates in areas such as pharmaceuticals, agrochemicals, and material polymers. While many halogenating agents have been developed, they continue to have low efficiency or selectivity, are difficult to handle, and often have limited substrate scope. To address this issue, our laboratory has developed novel halogenating agents with improved stability and efficiency. In these studies, we demonstrated a novel application of halogenating reagent, HCl·DMPU, in the nitrile synthesis. We developed a novel method for C−SCF3/SeCF3 cross-coupling reactions using gold redox catalysis. We developed a novel trifluoromethylating agent in a cost-effective and …


Small-Scale Variability In Warm Season, Precipitation Around An Urban Area: A Case Study Of Louisville-Jefferson County, Ky., Isaiah I. Kingsberry May 2022

Small-Scale Variability In Warm Season, Precipitation Around An Urban Area: A Case Study Of Louisville-Jefferson County, Ky., Isaiah I. Kingsberry

Electronic Theses and Dissertations

Numerous studies have detected anomalous precipitation patterns occurring up to 50 km downwind of major cities, providing major evidence that cities inadvertently modify precipitation and atmospheric circulations. Louisville is one such major city with a growing body of evidence of inadvertent precipitation modification. Despite these efforts, the physical mechanisms driving small-scale and unintentional changes in urban precipitation are little understood, being rooted largely in theory rather than in physical observations. This study seeks to build upon previous research by analyzing ground-based precipitation observations recorded by a high-density gauge network located within approximately 40 km of Louisville’s urban center. The results …


The Impact Of Sea-Level Rise In Numerically Modeled Landfalling Hurricanes: Katrina And The Gulf Coast., Serenity Nadirah Mercuri May 2022

The Impact Of Sea-Level Rise In Numerically Modeled Landfalling Hurricanes: Katrina And The Gulf Coast., Serenity Nadirah Mercuri

Electronic Theses and Dissertations

With climate change, landfalling hurricanes become an increasing threat to coastal regions. However, the interactions between the coastal landscape and landfalling hurricanes are often overlooked when addressing sea-level rise outside of inundation and independent of sea surface temperature. This study analyzed the potential impacts regarding structure and intensity as a result of sea-level rise in the Gulf of Mexico using the WRF-ARW numerical model coupled with a 1D ocean model. Analysis showed that 10 m windspeed from landfall forward was higher in modified coastlines, and minimum sea-level pressure post-landfall was consistently lower for modified runs where storms maintain a higher …


The Iwar Range + 21 Years: Cyber Defense Education In 2022, Joseph H. Schafer, Chris Morrell, Ray Blaine May 2022

The Iwar Range + 21 Years: Cyber Defense Education In 2022, Joseph H. Schafer, Chris Morrell, Ray Blaine

Military Cyber Affairs

Twenty-one years ago, The IWAR Range paper published by CCSC described nascent information assurance (now cybersecurity[1]) education programs and the inspiration and details for constructing cyber ranges and facilitating cyber exercises. This paper updates the previously published work by highlighting the dramatic evolution of the cyber curricula, exercise networks and ranges, influences, and environments over the past twenty years.

[1] In 2014, DoD adopted “cybersecurity” instead of “information assurance.” [34:1]


Hypergaming For Cyber: Strategy For Gaming A Wicked Problem, Joshua A. Sipper May 2022

Hypergaming For Cyber: Strategy For Gaming A Wicked Problem, Joshua A. Sipper

Military Cyber Affairs

Cyber as a domain and battlespace coincides with the defined attributes of a “wicked problem” with complexity and inter-domain interactions to spare. Since its elevation to domain status, cyber has continued to defy many attempts to explain its reach, importance, and fundamental definition. Corresponding to these intricacies, cyber also presents many interlaced attributes with other information related capabilities (IRCs), namely electromagnetic warfare (EW), information operations (IO), and intelligence, surveillance, and reconnaissance (ISR), within an information warfare (IW) construct that serves to add to its multifaceted nature. In this cyber analysis, the concept of hypergaming will be defined and discussed in …


Development Of A Novel Telemanipulation Framework For Human-Robot Collaboration Using Ptc Thingworx And Vuforia Studio, Preet Parag Modi May 2022

Development Of A Novel Telemanipulation Framework For Human-Robot Collaboration Using Ptc Thingworx And Vuforia Studio, Preet Parag Modi

Theses and Dissertations

Significant advancements in contemporary telehealth care applications are enforcing the demand for effective and intuitive telerehabilitation tools. The current techniques for observing live process parameters of robots frequently require complex and inefficient methods, which fundamentally limits the human administrator's ability to settle on the most educated decisions possible. Telemanipulation can minimize the distance and costs in varieties of robot applications, including industry for object manipulation and robot-aided rehabilitation. This research aims to develop a novel telemanipulation framework to deliver robot-assisted rehabilitation using PTC ThingWorx’s Industrial Internet of Things (IIoT), and Vuforia Studio’s Augmented Reality (AR) platforms. This communication architecture is …


Phytoplankton Mortality In An Urban Pond: Understanding The Roles Of Abiotic Factors, Grazing Pressure And Allelopathy, Lauren J. Simmons May 2022

Phytoplankton Mortality In An Urban Pond: Understanding The Roles Of Abiotic Factors, Grazing Pressure And Allelopathy, Lauren J. Simmons

Theses and Dissertations

Phytoplankton are found in dynamic aquatic environments, subjected to variations in abiotic (i.e., light, temperature, nutrients) and biotic (i.e., grazing, species interactions) conditions. Phytoplankton responses to these environmental variations are typically observed as changes in chlorophyll a (a surrogate for biomass), but such measurements do not provide information about individual taxa and cannot provide information about cell condition, for example, whether phytoplankton are living or dead. Furthermore, in examining the dynamics of phytoplankton, emphasis is placed on growth, but consideration of loss processes is usually limited to grazing and sedimentation, and not cell death The present study examined cell death …


The Butterfly Effect Of Fractals, Cody Watkins May 2022

The Butterfly Effect Of Fractals, Cody Watkins

Honors College Theses

This thesis applies concepts in fractal geometry to the relatively new field of mathematics known as chaos theory, with emphasis on the underlying foundation of the field: the butterfly effect. We begin by reviewing concepts useful for an introduction to chaos theory by defining terms such as fractals, transformations, affine transformations, and contraction mappings, as well as proving and demonstrating the contraction mapping theorem. We also show that each fractal produced by the contraction mapping theorem is unique in its fractal dimension, another term we define. We then show and demonstrate iterated function systems and take a closer look at …


An Agent-Based Exploration Of The Hurricane Forecast-Evacuation System Dynamics, Austin Reed Harris May 2022

An Agent-Based Exploration Of The Hurricane Forecast-Evacuation System Dynamics, Austin Reed Harris

Theses and Dissertations

In the mainland US, the hurricane-forecast-evacuation system is uncertain, dynamic, and complex. As a result, it is difficult to know whether to issue warnings, implement evacuation management strategies, or how to make forecasts more useful for evacuations. This dissertation helps address these needs, by holistically exploring the system’s complex dynamics from a new perspective. Specifically, by developing – and using – an empirically informed, agent-based modeling framework called FLEE (Forecasting Laboratory for Exploring the Evacuation-system). The framework represents the key, interwoven elements to hurricane evacuations: the natural hazard (hurricane), the human system (information flow, evacuation decisions), the built environment (road …


Guest Host Chemistry Part I: The Synthesis Of Metal Selective Sensors Part Ii: The Synthesis Of Antibiotic Precursors And Intermediates, Trevor Moss Hagemann May 2022

Guest Host Chemistry Part I: The Synthesis Of Metal Selective Sensors Part Ii: The Synthesis Of Antibiotic Precursors And Intermediates, Trevor Moss Hagemann

Theses and Dissertations

Part 1: Metal Selective Sensors

The work herein describes the creation of a library of sensors for the detection of metal ions in aqueous systems. The solid support these dyes are attached to facilitates a continuous measurement of metal ion concentrations in aqueous systems. The sensors are based on an azo dye core structure wherein detection of metal ions is observed by the change in absorbance of the dye upon binding. These sensors are capable of detecting metal ions in the ppb range, specific dyes interacting with specific metal ions cause distinct spectral changes, providing substantial information. the aggregate response …


Design And Synthesis Of Chiral And Achiral Benzodiazepines And Imidazodiazepines As Α–Subtype Selective Gabaar Positive Modulators To Treat Schistosomiasis, Epilepsy, Asthma And Some Mental Disorders, Md Yeunus Mian May 2022

Design And Synthesis Of Chiral And Achiral Benzodiazepines And Imidazodiazepines As Α–Subtype Selective Gabaar Positive Modulators To Treat Schistosomiasis, Epilepsy, Asthma And Some Mental Disorders, Md Yeunus Mian

Theses and Dissertations

Part I: Design, synthesis, and biological evaluation of non-sedating anti-schistosomal agents

Schistosomiasis is a parasitic flatworm infection with only one drug therapy currently on the market, praziquantel. An old lead identified by Roche, meclonazepam (US Patent 4031078A) displayed antiparasitic efficacy but was not pursued due to dose-limiting sedation in human clinical trials (S. Afr. Med J. 1979 Apr 14;55(16):617-8, PMID: 380021). However, given the superior spectrum of activity meclonazepam displays relative to praziquantel (which is unable to cure immature parasites within the host) and advances in the understanding of benzodiazepine SAR at human GABAARs, the study of this benzodiazepine was …


Understanding The Transition From General To Organic Chemistry, Hannah Chan May 2022

Understanding The Transition From General To Organic Chemistry, Hannah Chan

Student Scholar Symposium Abstracts and Posters

Organic chemistry is commonly known to have high failure rates and regarded as one of the most difficult courses offered in undergrad. This study assessed whether a modified general chemistry curriculum allowing for more time focused on foundational organic chemistry concepts in general chemistry can improve students’ grade outcome and/or self efficacy when transitioning from general to organic chemistry courses. Two separate variables were tested: grade outcome and self efficacy. Using an independent sample t-test, a comparison of the two groups (modified versus traditional general chemistry) was performed. Grades were assessed by giving students four questions (out of 4 points …


Changes In Western U.S. Streamflow Extremes Under Climate Change, Rama Bedri May 2022

Changes In Western U.S. Streamflow Extremes Under Climate Change, Rama Bedri

Student Scholar Symposium Abstracts and Posters

We are analyzing streamflow extremes in Western U.S. rivers due to climate change. Global warming causes natural disasters to reach extreme points and affects river volumes, snowfall, and precipitation amounts. We analyze the data for 17 stations in the Colorado River Basin, whose rivers provide Southern California’s drinking water supply. Disruptions in streamflow due to climate change affect the region’s water availability and make it difficult to predict future trends. We compared historical streamflow data to eight possible climate scenarios. The different scenarios are Warm Dry, Cool Wet, Average, and Other at emission levels of RCP 4.5 and 8.5. First, …


The One Who Won, Jeanna Polisini May 2022

The One Who Won, Jeanna Polisini

Student Scholar Symposium Abstracts and Posters

I am an adopted Asian American with an Italian last name who was raised in the Jewish faith. While I am one of the lucky ones, the One-Child Policy is responsible for how my life turned out. My intention is to confront the inhumanity of this horrific policy with my adoption story. Until policies personally affect someone’s life, many people do not think twice about the other country’s problems and their repercussions on a global level. For my senior exhibition, I created an autobiographical installation to explore my adoption story and how China’s inhumane dictatorship. The full immersive installation will …


Black Carbon Dominated Dust In Recent Radiative Forcing On Rocky Mountain Snowpacks, Kelly E. Gleason, Joseph R. Mcconnell, Monica M. Arienzo, Graham Sexstone, Stefan Rahimi May 2022

Black Carbon Dominated Dust In Recent Radiative Forcing On Rocky Mountain Snowpacks, Kelly E. Gleason, Joseph R. Mcconnell, Monica M. Arienzo, Graham Sexstone, Stefan Rahimi

Environmental Science and Management Faculty Publications and Presentations

The vast majority of surface water resources in the semi-arid western United States start as winter snowpack. Solar radiation is a primary driver of snowmelt, making snowpack water resources especially sensitive to even small increases in concentrations of light absorbing particles such as mineral dust and combustion-related black carbon (BC). Here we show, using fresh snow measurements and snowpack modeling at 51 widely distributed sites in the Rocky Mountain region, that BC dominated impurity-driven radiative forcing in 2018. BC contributed three times more radiative forcing on average than dust, and up to 17 times more at individual locations. Evaluation of …


Near-Inertial Wave Energetics Modulated By Background Flows In A Global Model Simulation, Keshav J. Raja, Maarten J. Buijsman, Jay F. Shriver, Brian K. Arbic, Oladeji Siyanbola May 2022

Near-Inertial Wave Energetics Modulated By Background Flows In A Global Model Simulation, Keshav J. Raja, Maarten J. Buijsman, Jay F. Shriver, Brian K. Arbic, Oladeji Siyanbola

Faculty Publications

We study the generation, propagation, and dissipation of wind-generated near-inertial waves (NIWs) in a global 1/25° Hybrid Coordinate Ocean Model (HYCOM) simulation with realistic atmospheric forcing and background circulation during 30 days in May–June 2019. The time-mean near-inertial wind power input and depth-integrated energy balance terms are computed for the total fields and the fields decomposed into vertical modes to differentiate between the radiative and (locally) dissipative components of NIW energy. Only 30.3% of the near-inertial wind input projects onto the first five modes, whereas the sum of the NIW energy in the first five modes adds up to 58% …


A Socio-Ecological Model To Assess Tuberculosis In Migrant Farmworkers In The Us-Mexico Border Region, Amit U. Raysoni May 2022

A Socio-Ecological Model To Assess Tuberculosis In Migrant Farmworkers In The Us-Mexico Border Region, Amit U. Raysoni

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The migrant and seasonal farmworker toiling in the fields and orchards of the United States of America surmounts innumerable problems daily. Some of these problems pertain to the overall health of the farmworker in addition to the various occupational hazards that he or she faces. This research paper focuses on Tuberculosis infection—both latent and active—in the migrant farmworkers in the United States with a special focus on the US-Mexico border. Using the Socio-Ecological Model as a theoretical framework, the TB health issues faced by this group are studied. The various determinants of health at every level of the Socio-Ecological Model …


Understanding Biogeochemical And Physical Controls On Methane Air-Sea Exchange Fluxes In The Pacific Ocean, Sarah Raney May 2022

Understanding Biogeochemical And Physical Controls On Methane Air-Sea Exchange Fluxes In The Pacific Ocean, Sarah Raney

Master's Theses

Methane and trace element samples were collected on GEOTRACES GP15 Pacific Meridional Transect (PMT) cruise conducted between the Aleutian Islands (57 °N) and Tahiti (20 °S) from September to November 2018. Uncertainty in methane air-sea exchange fluxes was determined using a propagation of errors approach. Fluxes ranged from -0.88 to 4.9 µmol CH4 m-2 d-1. Average CH4 flux along the Alaskan margin was 2.2 ± 2.9 µmol CH4 m-2 d-1. Methane fluxes decreased moving southward and increased to their open ocean maximum around 20 °N before declining in equatorial waters. Near …


Physics Of Electromagnetic Counterparts Of Binary-Neutron-Star Mergers, Shunke Ai May 2022

Physics Of Electromagnetic Counterparts Of Binary-Neutron-Star Mergers, Shunke Ai

UNLV Theses, Dissertations, Professional Papers, and Capstones

Binary neutron star (BNS) mergers are supposed to be the sources of a variety of astrophysical transients, including both gravitational wave (GW) and electromagnetic (EM) signals. The types and properties of the post-merger central product contain crucial information for many unsolved physical problems. Since the current GW detectors are not sensitive enough in kHz, only GWs from the inspiral phase can be detected, so that one cannot directly study the central products from GWs. EM signals can serve as probes to infer the type and properties of the central product. When a long-lived neutron star (NS) is formed after the …


Dust-Gas Dynamics Driven By The Streaming Instability With Various Pressure Gradients, Stanley Antedio Baronett May 2022

Dust-Gas Dynamics Driven By The Streaming Instability With Various Pressure Gradients, Stanley Antedio Baronett

UNLV Theses, Dissertations, Professional Papers, and Capstones

The radial pressure gradient (RPG), along the midplane of gaseous protoplanetary disks (PPD) – planetary nurseries – poses a severe obstacle to planet formation. Micron-sized dust grains, embedded in the disc, must quickly grow to kilometer-sized planetesimals – the building blocks of planets – before fatally drifting inwards, by RPG-induced gas drag, into a central host star. However, the RPG simultaneously powers one of the most robust processes to overcome this radial-drift barrier: the streaming instability (SI). Spontaneously triggered, the SI aerodynamically concentrates drifting dust via drag-induced, coupled interactions and feedback with the surrounding gas. In particular, the non-linear phase …


The Effects Of Winds On Accretion Disks And Spectra Of X-Ray Binaries And Active Galactic Nuclei, Shalini Ganguly May 2022

The Effects Of Winds On Accretion Disks And Spectra Of X-Ray Binaries And Active Galactic Nuclei, Shalini Ganguly

UNLV Theses, Dissertations, Professional Papers, and Capstones

Active galactic nuclei (AGNs) and X-ray binaries (XRBs) contain at their cores supermassive black holes (SMBH), and stellar mass black holes or neutron stars, respectively. These objects bind matter gravitationally, leading to the formation of accretion disks. The accretion of matter leads to efficient conversion of gravitational potential energy into radiation. When the force and/or energy imparted by this radiation on matter exceeds the attractive force due to the local gravitational field, it leads to the launching of matter in the form of outflows or winds. These outflows produce blueshifted (and occasionally redshifted) emission or absorption components in the spectra …


The Dissolution And Recovery Of Critical Materials (Li2co3 And Uf6) From Ionic Liquid, Cassara Higgins May 2022

The Dissolution And Recovery Of Critical Materials (Li2co3 And Uf6) From Ionic Liquid, Cassara Higgins

UNLV Theses, Dissertations, Professional Papers, and Capstones

Lithium and uranium are critical materials in both the energy industry and for national security. Lithium is necessary for the next generation of batteries and 6Li is valuable for the production of tritium necessary for both fusion energy and to maintain our nuclear stockpiles. Uranium is a fuel source or precursor fuel source for commercially operating nuclear fission power. The monitoring of uranium hexafluoride (UF6) enrichment at foreign facilities is important for the monitoring of nuclear safeguards and enforcement of non-proliferation treaties. Recovery methods for lithium at the end of life of batteries are necessary to ensure abundance of the …


A Survey Of The Br´Ezis-Nirenberg Problem And Related Theorems, Edward Huynh May 2022

A Survey Of The Br´Ezis-Nirenberg Problem And Related Theorems, Edward Huynh

UNLV Theses, Dissertations, Professional Papers, and Capstones

Nonlinear elliptic partial differential equations on bounded domains arise in several different areas of mathematics that include geometry, mathematical physics, and the calculus of variations. The Br ́ezis-Nirenberg problem is concerned with a boundary-value problem that is intimately connected to the existence of positive solutions of the Yamabe problem, of non-minimal solutions to Yang-Mills functionals, and of extremal functions to several important inequalities. Results on existence and uniqueness have been obtained in cases when the exponent is sub-critical, but such results have not been obtained when the exponent is critical due to a lack of compactness. The earliest results obtained …


Positive Solutions To Semilinear Elliptic Equations With Logistic-Type Nonlinearities And Harvesting In Exterior Domains, Eric Jameson May 2022

Positive Solutions To Semilinear Elliptic Equations With Logistic-Type Nonlinearities And Harvesting In Exterior Domains, Eric Jameson

UNLV Theses, Dissertations, Professional Papers, and Capstones

Existing results provide the existence of positive solutions to a class of semilinear elliptic PDEs with logistic-type nonlinearities and harvesting terms both in RN and in bounded domains U ⊂ RN with N ≥ 3, when the carrying capacity of the environment is not constant. We consider these same equations in the exterior domain Ω, defined as the complement of the closed unit ball in RN , N ≥ 3, now with a Dirichlet boundary condition. We first show that the existing techniques forsolving these equations in the whole space RN can be applied to the exterior domain with some …