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Full-Text Articles in Physical Sciences and Mathematics

Are Gender And Social Disparities Associated With Stem Persistence In Kentucky Colleges?, Riley E. Hicks, Wilson Gonzalez-Espada Apr 2023

Are Gender And Social Disparities Associated With Stem Persistence In Kentucky Colleges?, Riley E. Hicks, Wilson Gonzalez-Espada

2023 Celebration of Student Scholarship - Poster Presentations

Children have the right to receive a quality education, but concerns about county disparities in school funding, facilities, and resources exist. This is known as the "zip code effect". Because high school STEM classes require lab space, materials, equipment, and specialized teachers, disparities in school funding can impact students who want STEM careers.


Visual Pollution Classification Using Convolutional Neural Networks, Jacob Vogelpohl, Heba Elgazzar Apr 2023

Visual Pollution Classification Using Convolutional Neural Networks, Jacob Vogelpohl, Heba Elgazzar

2023 Celebration of Student Scholarship - Poster Presentations

Visual pollution is an impairment on an individual's ability to enjoy their surroundings. It usually takes the form of a messy and chaotic environment that can cause overstimulation of the visual senses. This includes trash, advertisements, construction, electric cables, and similar objects. Convolutional Neural Networks (CNNs) are a form of artificial intelligence that use supervised learning to process and classify images. In this research, a CNN processed images of city streets and classified them as polluted or not polluted based on the visual characteristics that it learned from during its training period. The CNN achieved a training accuracy of 98% …


Predicting The Mechanism And Products Of Cs2 Capture By Nh3 - An Exemplar Benchmark Study, Shelbie A. Black, David A. Dixon, Zachary R. Lee Apr 2023

Predicting The Mechanism And Products Of Cs2 Capture By Nh3 - An Exemplar Benchmark Study, Shelbie A. Black, David A. Dixon, Zachary R. Lee

2023 Celebration of Student Scholarship - Poster Presentations

Carbon disulfide is a toxic gas emitted from industrial plants and a common greenhouse gas. Acute poisonings from carbon disulfide are rare, but recurring exposure to low doses can have long term health effects. Currently, there are two approaches being considered for the removal of acid gas pollutants: (1) sequester these gases from the atmosphere or (2) remove these gases directly upon combustion (post-combustion). Potential energy surfaces (PES) for a series of CS2 capture reactions by NH3 in the presence H2O were calculated at the MP2/a(D+d) evel in the gas phase. G3(MP2) and FPD calculations are in progress. Extensive thermodynamic …


A Targeted Study On The Match Between Cybersecurity Higher Education Offerings And Workforce Needs, Diane Murphy, Nektaria Tryfona, Andrew M. Marshall Apr 2023

A Targeted Study On The Match Between Cybersecurity Higher Education Offerings And Workforce Needs, Diane Murphy, Nektaria Tryfona, Andrew M. Marshall

Virginia Journal of Science

The Cybersecurity Workforce Gap is a call to action on a two-fold problem: the worldwide shortage of qualified cybersecurity workers and the need to develop a growing highly-knowledgeable, agile, well-trained cybersecurity workforce. This paper presents a methodological approach to achieve this goal in the Northern Virginia area. The area is characterized by an abundance of cyber-related industries, government agencies, and large businesses with high demand of skilled cybersecurity workers; at the same time, academic institutions offer cutting edge education and training access to highly capable students. Central to this methodology is the collaboration between local academia and industry and it …


On Electric Vehicles And Environmental Policies For Innovation, A Book Review Of The Global Rise Of The Modern Plug-In Electric Vehicle: Public Policy, Innovation, And Strategy, By John Graham, Shi-Ling Hsu Apr 2023

On Electric Vehicles And Environmental Policies For Innovation, A Book Review Of The Global Rise Of The Modern Plug-In Electric Vehicle: Public Policy, Innovation, And Strategy, By John Graham, Shi-Ling Hsu

Scholarly Publications

Electric vehicles have been in existence for over a century. Impetus and progress towards commercialization have been uneven. For the most part, government policy on electric vehicle development has consisted of government funding and other support for research and development. The long, meandering path that has now resulted in the emergence of Tesla as an industry leader has been documented carefully in John Graham's The Global Rise of the Modern Plug-in Electric Vehicle. Graham's account is remarkably broad and thorough, leaving few stones unturned, and comprehensively detailing the history of electric vehicle policy in a number of countries, and often …


Classification Of Seven-Dimensional Solvable Lie Algebras With A5,2 And A5,3 Nilradicals, Robert Dolan Apr 2023

Classification Of Seven-Dimensional Solvable Lie Algebras With A5,2 And A5,3 Nilradicals, Robert Dolan

Honors Projects

This paper provides a classification of seven-dimensional indecomposable solvable Lie algebras over the reals for which the nilradical is isomorphic to A5,2 and A5,3. We follow a technique that was first introduced by Mubarakzyanov.


Modeling Immune System Dynamics During Hiv Infection And Treatment With Differential Equations, Nicole Rychagov Apr 2023

Modeling Immune System Dynamics During Hiv Infection And Treatment With Differential Equations, Nicole Rychagov

CODEE Journal

An inquiry-based project that discusses immune system dynamics during HIV infection using differential equations is presented. The complex interactions between healthy T-cells, latently infected T-cells, actively infected T-cells, and the HIV virus are modeled using four nonlinear differential equations. The model is adapted to simulate long term HIV dynamics, including the AIDS state, and is used to simulate the long term effects of the traditional antiretroviral therapy (ART). The model is also used to test viral rebound over time of combined application of ART and a new drug that blocks the reactivation of the viral genome in the infected cells …


Longitudinal Changes In Alzheimer’S-Related Plasma Biomarkers And Brain Amyloid, Murat Bilgel, Abhay Moghekar, Henrik Zetterberg, Bruno Jedynak, Multiple Additional Authors Apr 2023

Longitudinal Changes In Alzheimer’S-Related Plasma Biomarkers And Brain Amyloid, Murat Bilgel, Abhay Moghekar, Henrik Zetterberg, Bruno Jedynak, Multiple Additional Authors

Mathematics and Statistics Faculty Publications and Presentations

Introduction Understanding longitudinal plasma biomarker trajectories relative to brain amyloid changes can help devise Alzheimer’s progression assessment strategies.

Methods We examined the temporal order of changes in plasma amyloid-β ratio (Aβ42/Aβ40), glial fibrillary acidic protein (GFAP), neurofilament light chain (NfL), and phosphorylated tau ratios (p-tau181/Aβ42, p-tau231/Aβ42) relative to 11C-Pittsburgh compound B (PiB) positron emission tomography (PET) cortical amyloid burden (PiB−/+). Participants (n = 199) were cognitively normal at index visit with a median 6.1-year follow-up.

Results PiB groups exhibited different rates of longitudinal change in Aβ42/Aβ40 (β = 5.41 × 10-4, SE = 1.95 × 10-4, p = 0.0073). …


A Novel Near-Surface Wave-Coherent Instantaneous Profiling System For Atmospheric Measurements, Mathew J. Stanek, Douglas M. Pastore, Erin E. Hackett Apr 2023

A Novel Near-Surface Wave-Coherent Instantaneous Profiling System For Atmospheric Measurements, Mathew J. Stanek, Douglas M. Pastore, Erin E. Hackett

Marine Science

Large knowledge gaps concerning the effect of ocean surface waves on near-surface vertical distributions of temperature and humidity exist due to practical limitations and sensor fidelity challenges of direct measurements. Measurements of temperature and humidity are classically made using rocket- or radiosondes and fixed weather stations and can utilize a tethered profiling system. However, these measurement systems have limitations when obtaining wave-coherent measurements near the sea surface. Consequently, boundary layer similarity models are commonly employed to fill in near-surface measurement gaps despite the documented shortcomings of the models in this region. Thus, this manuscript presents a near-surface wave-coherent measurement platform …


Computational Design Of Fiber-Optic Probes For Biosensing, Suwarna Karna Apr 2023

Computational Design Of Fiber-Optic Probes For Biosensing, Suwarna Karna

Electrical Engineering Theses

This thesis presents a study on the optical characteristics of hollow-core photonic crystal fibers (HC-PCFs) with a band gap cladding structure and their applications in optical fiber sensing. This 800B HC-PCF exhibited excellent optical properties and has a flexible structure, which makes them suitable for a wide range of industrial applications. Finite element simulations and structural optimization designs were conducted using the surface plasmon resonance (SPR) technique to determine the optimal performance parameters of the 800B HC-PCF. The fiber was further modified using the SPR technique to improve its practical detection capabilities. The performance of the modified fiber was observed …


Extraction And Analytical Method For N-Nitrosoatrazine Using Liquid Chromatography Paired With Tandem Mass Spectrometry, Carolyn Billings Apr 2023

Extraction And Analytical Method For N-Nitrosoatrazine Using Liquid Chromatography Paired With Tandem Mass Spectrometry, Carolyn Billings

Honors Program: Senior Projects (Public)

Atrazine is an herbicide used in the United States to control weeds. When combined with nitrite, atrazine can be nitrosated to form N-nitrosoatrazine (NNAT) in vivo and in vitro under acidic conditions. Atrazine can also be metabolized to atrazine mercapturate, deethylatrazine (DEA), didealkylatrazine (DDA), and deisopropylatrazine (DIA). Atrazine is monitored in drinking water due to its possible carcinogenicity. The objective of this study was to develop extraction and analytical methods for NNAT, atrazine, and atrazine metabolites. An instrument detection limit, extraction methods comparison, and extraction method detection limit were determined. To compare methods, Fischer 344 rat tissue samples were …


An Analysis Of Energy Production And Efficiency In Various Longbow Archery Models, Hannah Mcpherson Apr 2023

An Analysis Of Energy Production And Efficiency In Various Longbow Archery Models, Hannah Mcpherson

Honors Projects

An analysis of the energy production and efficiency of three lab-tested longbow models is undertaken. The first model, which is constructed to not allow flexing of limbs and which uses a frictionless cart and track in place of an arrow, demonstrated an efficiency of 50% +/- 40%. The second model, which is constructed similarly to the first with the exception of a wooden dowel now being used as an arrow-like object, demonstrated an efficiency of 13% +/- 3%. The last model, a 3D printed longbow with flexible limbs using the wooden dowel as an arrow-like object, demonstrated an efficiency of …


Statistical Clustering Of Networks With Additional Information, Paul Atandoh Apr 2023

Statistical Clustering Of Networks With Additional Information, Paul Atandoh

Dissertations

As the online market grows rapidly, many companies and researchers are interested in analyzing product review dataset which includes ratings and text review data. In the first project, we mainly focus on analyzing the text review data. In the current literature, it is common to use only text analysis tools to analyze review dataset. But in our work, we propose a method that utilizes both a text analysis method such as topic modeling and a statistical network model to build network among individuals and find interesting communities. We introduce a promising framework that incorporates topic modeling technique to define the …


Using Visual Imagery To Develop Multiplication Fact Strategies, Gina Kling Apr 2023

Using Visual Imagery To Develop Multiplication Fact Strategies, Gina Kling

Dissertations

The learning of basic facts, or the sums and products of numbers 0–10 and their related differences and quotients, has always been a high priority for elementary school teachers. While memorization of basic facts has been a hallmark of elementary school, current recommendations focus on a more nuanced development of fluency with these facts. Fluency is characterized by the ability to demonstrate flexibility, accuracy, efficiency, and appropriate strategy use. Despite recommendations to focus on strategy use, there is insufficient information on instructional approaches that are effective for developing strategies, particularly for multiplication facts. Using visual imagery with dot patterns has …


Irregular Domination In Graphs, Caryn Mays Apr 2023

Irregular Domination In Graphs, Caryn Mays

Dissertations

Domination in graphs has been a popular area of study due in large degree to its applications to modern society as well as the mathematical beauty of the topic. While this area evidently began with the work of Claude Berge in 1958 and Oystein Ore in 1962, domination did not become an active area of research until 1977 with the appearance of a survey paper by Ernest Cockayne and Stephen Hedetniemi. Since then, a large number of variations of domination have surfaced and provided numerous applications to different areas of science and real-life problems. Among these variations are domination parameters …


Design And Implementation Of An Efficient Priority Queue Data Structure, James A. Rhodes Apr 2023

Design And Implementation Of An Efficient Priority Queue Data Structure, James A. Rhodes

Dissertations

Priority queues are one of the most useful data structures. Research to improve the efficiency of priority queues is on-going in the field of Computer Science. We have designed and implemented a priority queue based on buckets that improves the performance of applications that utilize min/max heaps. The data structure improves an application’s insertion time and deletion time, and thus its overall execution time. We demonstrate the performance improvements in a wide variety of applications. Every one of the applications that we implemented is well-known, and important in the Computer Science field. We also demonstrate that the performance gains over …


Development And Validation Of A Liquid Chromatography-Tandem Mass Spectrometry Method For The Determination Of Temozolomide In Mouse Brain Tissue, Raghavi Kakarla, Kimberly Yacoub, Rebecca L. Bearden, Aimin Zhou, Sanjib Mukherjee, Frank Y. Shan, Baochuan Guo Apr 2023

Development And Validation Of A Liquid Chromatography-Tandem Mass Spectrometry Method For The Determination Of Temozolomide In Mouse Brain Tissue, Raghavi Kakarla, Kimberly Yacoub, Rebecca L. Bearden, Aimin Zhou, Sanjib Mukherjee, Frank Y. Shan, Baochuan Guo

Chemistry Faculty Publications

Temozolomide is a Food and Drug Administration-approved anticancer drug that has poor drug delivery via oral or intravenous routes. A potential strategy to combat this problem is investigating alternative routes of administration, requiring quantitation of the drug in the brain tissues by liquid chromatography-mass spectrometry. However, current methods used to extract the drug from brain tissues resulted in poor recovery and substantial matrix effects. Herein, we reported a new two-step extraction method that involves the use of Proteinase K to lyse tumor tissues to efficiently release the drug, followed by ethanol protein precipitation. The extracts were then separated on a …


Comprehensive Planning For The Promotion Of Sustainable Development In Georgetown County., Michael Meagher Apr 2023

Comprehensive Planning For The Promotion Of Sustainable Development In Georgetown County., Michael Meagher

Goal 11: Sustainable Cities and Communities

No abstract provided.


The Importance Of Accessible Government Data In Advancing Environmental Justice, Frank D. Lomonte, Daniel Delgado Apr 2023

The Importance Of Accessible Government Data In Advancing Environmental Justice, Frank D. Lomonte, Daniel Delgado

William & Mary Environmental Law and Policy Review

Part I of this Article sets forth the history and animating principles of the environmental justice movement in the United States during the 1970s, which developed as an adjunct to the larger civil rights movement. Part II then turns to the role of documents and data in exposing where toxins present a risk to public health and where documentation habitually falls short. It discusses how freedom of information laws can unlock access to the documents and data that quantify environmental hazards but also how those laws fail to produce reliable results because of the influence of regulated industries. Part III …


Defining Safe Training Datasets For Machine Learning Models Using Ontologies, Lynn C. Vonder Haar Apr 2023

Defining Safe Training Datasets For Machine Learning Models Using Ontologies, Lynn C. Vonder Haar

Doctoral Dissertations and Master's Theses

Machine Learning (ML) models have been gaining popularity in recent years in a wide variety of domains, including safety-critical domains. While ML models have shown high accuracy in their predictions, they are still considered black boxes, meaning that developers and users do not know how the models make their decisions. While this is simply a nuisance in some domains, in safetycritical domains, this makes ML models difficult to trust. To fully utilize ML models in safetycritical domains, there needs to be a method to improve trust in their safety and accuracy without human experts checking each decision. This research proposes …


Socially Aware Natural Language Processing With Commonsense Reasoning And Fairness In Intelligent Systems, Sirwe Saeedi Apr 2023

Socially Aware Natural Language Processing With Commonsense Reasoning And Fairness In Intelligent Systems, Sirwe Saeedi

Dissertations

Although Artificial Intelligence (AI) promises to deliver ever more user-friendly consumer applications, recent mishaps involving fake information and biased treatment serve as vivid reminders of the pitfalls of AI. AI can harbor latent biases and flaws that can cause harm in diverse and unexpected ways. It is crucial to understand the reasons for, mechanisms behind, and circumstances under which AI can fail. For instance, a lack of commonsense reasoning can lead to biased or unfair decisions made by Machine Learning (ML) systems. For example, if an ML system is trained on data that is biased or unrepresentative of the real …


That’S My Deity: An Examination Of Online Lokean Cultures Through Log-Linear Modeling, Mary Bernstein Apr 2023

That’S My Deity: An Examination Of Online Lokean Cultures Through Log-Linear Modeling, Mary Bernstein

Senior Theses

A rise in online religious communities and the growth of so-called ‘Old World’ religions are reflected in the internet’s subcultures of Neopaganism, a growing religious movement that has been documented in America since the 1960s. The religions under this umbrella movement vary drastically and include belief systems such as Wicca, Druidry, and deity worship. Belief systems under this movement lack the traditional hierarchy found in structured religion and lack a singular sacred text. As such, believers usually find and support one another not through a physical sacred place of meeting, but through an online community that acts as sacred space. …


A Short Solution Of The Kissing Number Problem In Dimension Three, Alexey Glazyrin Apr 2023

A Short Solution Of The Kissing Number Problem In Dimension Three, Alexey Glazyrin

School of Mathematical & Statistical Sciences Faculty Publications

We give a short solution of the kissing number problem in dimension three.


Ramanujan–Sato Series For 1/Π, Timothy Huber, Daniel Schultz, Dongxi Ye Apr 2023

Ramanujan–Sato Series For 1/Π, Timothy Huber, Daniel Schultz, Dongxi Ye

School of Mathematical & Statistical Sciences Faculty Publications

We compute Ramanujan–Sato series systematically in terms of Thompson series and their modular equations. A complete list of rational and quadratic series corresponding to singular values of the parameters is derived.


P-Adic Cellular Neural Networks: Applications To Image Processing, B. A. Zambrano-Luna, Wilson A. Zuniga-Galindo Apr 2023

P-Adic Cellular Neural Networks: Applications To Image Processing, B. A. Zambrano-Luna, Wilson A. Zuniga-Galindo

School of Mathematical & Statistical Sciences Faculty Publications

The p-adic cellular neural networks (CNNs) are mathematical generalizations of the neural networks introduced by Chua and Yang in the 80s. In this work we present two new types of -adic CNNs that can perform computations with real data, and whose dynamics can be understood almost completely. The first type of networks are edge detectors for grayscale images. The stationary states of these networks are organized hierarchically in a lattice structure. The dynamics of any of these networks consists of transitions toward some minimal state in the lattice. The second type is a new class of reaction–diffusion networks. We investigate …


Nano-Supported Biocatalysts For Efficient Wastewater Remediation, Khadega Abobaker Al-Maqdi Apr 2023

Nano-Supported Biocatalysts For Efficient Wastewater Remediation, Khadega Abobaker Al-Maqdi

Dissertations

The existence of various bioactive organic pollutants in wastewater and municipal water sources has raised concerns regarding their potential effects on human health. As a result, different techniques are being explored to effectively break down these persistent organic pollutants. Peroxidases have recently emerged as a new approach to remediation that may have advantages over traditional methods. However, evaluating the effectiveness of different peroxidases in breaking down various emerging pollutants can be time-consuming and difficult. In this study, a quick and reliable method was developed to test the degradability of 21 emerging pollutants by five different peroxidases (soybean peroxidase, chloroperoxidase, lactoperoxidase, …


Interactive Emirate Sign Language E-Dictionary Based On Deep Learning Recognition Models, Ahmed Abdelhadi Abdelhadi Apr 2023

Interactive Emirate Sign Language E-Dictionary Based On Deep Learning Recognition Models, Ahmed Abdelhadi Abdelhadi

Theses

According to the ministry of community development database in the United Arab Emirates (UAE) about 3065 people with disabilities are hearing disabled (Emirates News Agency - Ministry of Community Development). Hearing-impaired people find it difficult to communicate with the rest of society. They usually need Sign Language (SL) interpreters but as the number of hearing-impaired individuals grows the number of Sign Language interpreters can almost be non-existent. In addition, specialized schools lack a unified Sign Language (SL) dictionary, which can be linked to the Arabic language being of a diglossia nature, hence many dialects of the language co-exist. Moreover, there …


Valuation Of Asian Options In A High Volatility Market With Jumps, Zeeshan Khalid Apr 2023

Valuation Of Asian Options In A High Volatility Market With Jumps, Zeeshan Khalid

Theses

The evaluation of financial derivatives represents a central part of financial risk management. There are many types of derivatives among other path-dependent options. In this study, we aim at valuing Asian options. They are path dependent and have several benefits. For instance, their values are habitually lower than European options. Also, an Asian option on a commodity drops the risk value close to maturity. Though, the disadvantage is that they are in general difficult to value since the distribution of the payoff is usually unknown. It is agreed in the literature that a stochastic process with a jumps model for …


Highly Pathogenic Avian Influenza A(H5n1) Virus Outbreak In New England Seals, United States, Wendy Puryear, Kaitlin Sawatzki, Nichola Hill, Alexa Foss, Jonathon J. Stone, Lynda Doughty, Dominique Walk, Katie Gilbert, Maureen Murray, Elena Cox, Priya Patel, Zak Mertz, Stephanie Ellis, Jennifer Taylor, Deborah Fauquier, Ainsley Smith, Robert A. Digiovanni, Adriana Van De Guchte, Ana Silvia Gonzalez-Reiche, Zain Khalil, Harm Van Bakel, Mia K. Torchetti, Kristina Lantz, Julianna B. Lenoch, Jonathan Runstadler Apr 2023

Highly Pathogenic Avian Influenza A(H5n1) Virus Outbreak In New England Seals, United States, Wendy Puryear, Kaitlin Sawatzki, Nichola Hill, Alexa Foss, Jonathon J. Stone, Lynda Doughty, Dominique Walk, Katie Gilbert, Maureen Murray, Elena Cox, Priya Patel, Zak Mertz, Stephanie Ellis, Jennifer Taylor, Deborah Fauquier, Ainsley Smith, Robert A. Digiovanni, Adriana Van De Guchte, Ana Silvia Gonzalez-Reiche, Zain Khalil, Harm Van Bakel, Mia K. Torchetti, Kristina Lantz, Julianna B. Lenoch, Jonathan Runstadler

United States Department of Agriculture Wildlife Services: Staff Publications

We report the spillover of highly pathogenic avian influenza A(H5N1) into marine mammals in the northeastern United States, coincident with H5N1 in sympatric wild birds. Our data indicate monitoring both wild coastal birds and marine mammals will be critical to determine pandemic potential of influenza A viruses.


Survival Models With Background Mortality, Shujie Chen Apr 2023

Survival Models With Background Mortality, Shujie Chen

Theses and Dissertations

In this dissertation, we focus on studying three mixture cure models with background mortality. With the development of treatment, patients may be cured and suffer from other cause of death. The cure model with background mortality can measure the population cure which refers to the patients with comparable mortality with their counterpart in general population. Three types of survival models are investigated, including generalized odds rate (GOR) model, cure model with background mortality for right censoring and interval censoring, and extended illness death model via incorporating “cure” fraction. All methods are validated via comprehensive simulation studies and real data application. …