Physical Sciences and Mathematics Commons^™

An Investigative Study Of Potential Factors That Contribute To High Under-Five Mortality Rate In Africa, David Banahene

Theses and Dissertations

Under-Five Mortality remains a significant challenge in developing countries, especially in Africa. The United Nations has implemented various measures, such as the Millennium Development Goals (MDGs) and Sustainable Development Goals (SDGs), to combat this issue. However, the success of these initiatives is uncertain. Our study investigates the social, economic, and environmental factors contributing to high Under-Five Mortality rates in African countries, using data from 1985 to 2020.We analyzed 53 African countries, partitioning them into training (45 countries) and testing data (8 countries). We conducted Multiple Linear Regression analysis and assessed the model performance using R-squared values and Root-Mean-Squared-Error (RMSE) values. …

Creation Of A College Math Club For High School Students, Lilian N. Chavez

Theses and Dissertations

This study aimed to investigate the variables that contribute to high school students' desire to join a math club, specifically the FMiM VIP Club, which is an extension of UTRGV's Follow Me into Math research project. The research utilized multiple questionnaire s to examine the combination of factors that contribute to the students' attitudes toward the math club. The participants were high school Algebra 2 students from two different schools, and the study was conducted in two stages. The first stage was conducted in the Spring of 2022, focusing on girls' math identity and their interactions with the FMiM VIP …

Effect Of Elevated Temperature And Roundup Exposure On Oxidative Stress And Antioxidant Status In The American Oyster, Afsana Chowdhury

Theses and Dissertations

Aquatic organisms are frequently exposed to various environmental stressors. In this study, we observed the short-term (1-week) combined dose-dependent effect of Roundup, a glyphosate-based herbicide, and high temperature (30°C) on the morphology of gills and digestive glands, expression of heat shock protein-70 (HSP70), dinitrophenyl protein (DNP), nitrotyrosine protein (NTP), antioxidant enzymes such as catalase (CAT) and superoxidase dismutase (SOD) in tissues of American oyster (Crassostrea virginica). Histological analyses showed an increase in mucous production in the gills and digestive glands, hemocyte aggregation in the connective tissues as well as structural change of the lumen in the digestive glands …

Analysis Of Post-Translational Modifications (Ptm) Crosstalk, Amit Das

Theses and Dissertations

Mass spectrometry-based proteomics is a powerful tool for identifying post-translational modifications (PTMs) across the proteome. O-GlcNAcylation and phosphorylation are two PTMs that play crucial roles in regulating cellular processes, including cardiac contractile function. Dysregulation of these PTMs has been implicated in the development and progression of diabetic cardiomyopathy. In this study, we aimed to investigate the interplay between O-GlcNAcylation and phosphorylation in healthy and type 2 diabetic hearts, with a specific focus on the functional relationships between these PTMs and their potential therapeutic implications.

Utilizing mass spectrometry data, we identified and quantified specific PTMs on myofilament proteins, uncovering 1354 O-GlcNAcylated …

Microwave-Assisted Depolymerization Of Poly (Ethylene Terephthalate) Via Ethanolysis, Mayra Alejandra Gomez Cortez

Theses and Dissertations

In the search of providing an alternative form of combating the complex environmental concerns rising from the rapid growth of poly (ethylene terephthalate) waste in the world, this research focused on investigating the chemical recycling of PET via ethanolysis. Parameters such as temperature, reaction time, catalyst usage and concentration were investigated to promote depolymerization.

In this work, ethanolysis of waste PET under microwave irradiation was investigated using organocatalysts 1,5,7-Triazabicyclo [4.4.0] dec5-ene (TBD) and 1,8-Diazabicyclo [5.4.0] underc-7-ene (DBU). We evaluated the effectiveness of reaction conditions through a series of experiments and determined the optimum conditions as follows: 0.5 g of PET, …

Determination Of Effective Index Of Refraction Of Structured Materials (Photonic Crystals), Md Arafat Hossain

Theses and Dissertations

Photonic crystals have been widely studied by researchers due to their ability to control light propagation in all spatial directions. For example, 2D photonic crystals can be made of dielectric rods arranged in a square lattice. When light propagates through 2D photonic crystals, it experiences multiple scatterings by the crystal centers. The superposition of all scattered waves forms the transmitted field largely dependent upon the effective index of refraction of the structured material. We propose a method to determine the effective index of refraction through such materials with the Finite-Difference Time-Domain (FDTD) model. We set up the interface of two …

Flow Monitoring And Tidal Exchange Ratio Estimation For The Bahia Grande After Widening Of The Carl Joe Gayman Pilot Channel: Bahia Grande, Cameron County, Tx, Sabas Lopez Iii

Theses and Dissertations

The Bahia Grande (BG) is an 8,500-acre set of coastal bays and wetlands located between Brownsville and Port Isabel, Tx, near the Gulf of Mexico (GOM) coastline. In 2005, the Carl Joe Gayman Pilot Channel was constructed to address hypersalinity concerns that resulted from natural and anthropogenically-caused tidal isolation since the early 1940’s. In 2022, the Texas General Land Office (GLO) increased the channel’s width and depth in anticipation of increasing tidal exchange ratios by a factor of two to three. Once the channel widening was complete, two SL-1500-3G side-looking acoustic doppler current profilers (ADCPs) were periodically deployed beneath the …

Evaluation Of Black Holes In An Evolving Universe, John P. Naan

Theses and Dissertations

There are various solutions to the Einstein field equations that represent different physical assumptions, but how to represent multiple black holes within an expanding universe remains an area of open interest. The first step to resolving this question involves evaluating spacetime models that contain a single black hole in an expanding universe. Here, we are primarily interested in understanding the energy distribution of black hole models by solving Einstein's equations using the associated spacetime metric and comparing the propagation of waves within the model against other known spacetime models. Specifically, we will evaluate the combined Schwarschild-de Sitter solution under a …

Effects Of Missing Data Imputation Methods On Univariate Time Series Forecasting With Arima And Lstm, Nicholas Niako

Theses and Dissertations

Missing data are common in real-life studies and missing observations within the univariate time series cause analytical problems in the flow of the analysis. Imputation of missing values is an inevitable step in the analysis of every incomplete univariate time series data. The reviewed literature has shown that the focus of existing studies is on comparing the distribution of imputed data. There is a gap of knowledge on how different imputation methods for univariate time series data affect the fit and prediction performance of time series models. In this work, we evaluated the predictive performance of autoregressive integrated moving average …

Problems In Algorithmic Self-Assembly And A Genetic Approach To Patterns, Andrew Rodriguez

Theses and Dissertations

As it becomes increasingly harder to make transistors smaller, replacements for traditional silicon computers become sought after. To study the computing power of these potential computers, various theoretical models have been proposed, such as the abstract Tile Assembly Model (aTAM) and chemical reaction networks (CRNs). This thesis compiles research in various models such as the aTAM, Tile Automata, and CRNs. This work shows an investigation of covert computation in the aTAM and an evolutionary algorithm to approximate solutions to the pattern self-assembly tile set synthesis (PATS) problem. Next, optimal state complexity for building squares in Tile Automata is shown along …

The Effect Of Cybersecurity Training On Government Employee’S Knowledge Of Cybersecurity Issues And Practices, Juan Jaime Saldana Ii

Theses and Dissertations

There is an ever-pressing need for cybersecurity awareness and implementation of learning strategies in the workplace to mitigate the increased threat posed by cyber-attacks and exacerbated by an untrained workforce. The lack of cybersecurity knowledge amongst government employees has increased to critical levels due to the amount of sensitive information their agencies are responsible for. The digital compromise of a government entity often leads to a compromise of constituent data along with the disruption of public services (Axelrod, 2019; Yazdanpanahi, 2021). The need for awareness is further complicated by agencies looking to cater to a digital culture looking for a …

A Machine Learning Approach To Obese-Inflammatory Phenotyping, Tania Mayleth Vargas

Theses and Dissertations

Obesity is the accumulation of an abnormal, or excessive, amount of fat in the body, which can have negative effects on overall health. This excess accumulation of macronutrients in adipose tissue can cause the release of inflammatory mediators, leading to a proinflammatory state. Inflammation is a known risk factor for various health conditions, including cardiovascular diseases, metabolic syndrome, and diabetes. This study sought to examine the use of data mining methods, particularly clustering algorithms, to identify inflammatory biomarker phenotypes and their association with obesity in a local adolescent population. The algorithms evaluated in this study included: k-means, Ward's hierarchical …

Modeling User Behavior For Cyber Security With Formal Methods And Agent Based Simulation, Hamdah Albalawi

Theses and Dissertations

Despite society’s positive outlook, technology poses real cyber security threats. Technology’s benefits can sometimes make it difficult to believe that potential threats lurk behind every device and platform. As cybercrime rises, we have come to rely increasingly on flawed devices and services. As cyberattacks become more prevalent, security professionals are committed to developing more robust and dependable security solutions. In cyber security, human error is regarded as the weakest link since all technical security solutions are vulnerable to human error. Among other human characteristics, risk-taking, logical decision-making, extraversion, and gender can significantly affect cyber security. However, there still is the …

Towards Explainable Ai: Predicting Linear And Nonlinear Feature Relations Of Datasets, Nimmy Chhaganbhai Patel

Theses and Dissertations

Artificial Intelligence (AI) makes critical decisions in an opaque way without explaining the reasoning behind them. Decision support systems are often built as black boxes. This has generated interest in Explainable AI (XAI), an area of research that explains AI algorithms and provides more insight into their internal decision-making process. Advancements in XAI have enhanced machine learning (ML) models’ interpretability, explainability, and transparency. Additionally, there has been speculation on whether it is possible to predict the type of dataset used in the model by analyzing the results. In this research, we proposed a methodology for determining the linearity or non-linearity …

Design And Synthesis Of Novel Peptide-Metal Organic Frameworks, Moustafa Mahmoud Abdel Wahid Hamaad

Theses and Dissertations

Metal-organic frameworks (MOFs) are a class of crystalline porous materials with extended network structures formed through the reticular assembly of inorganic and organic molecular building blocks through strong coordination bonds. Compared to other porous materials, MOFs offer a high degree of structural diversity as their shape and pore size as well as functionality can tuned by the precise selection and design of their metal centers and organic struts. Due to their high surface areas, pore volumes, and the possibility of introduction of a myriad of chemical functionalities in their structures, MOFs have gained popularity for applications in many fields such …

Anti-Doping Crisis In Sports, What's Next? Ion Mobility-Mass Spectrometry For The Study Of Anabolic Androgenic Steroids, Diana Constanza Velosa

Theses and Dissertations

The main objective of this work is to augment both qualitative and quantitative measures of anabolic androgenic steroids (AAS) with ion mobility-mass spectrometry (IM-MS), laying the foundation for implementation into analytical drug testing laboratories. AAS testing requires high sensitivity and specificity. IM-MS is presented as an emerging technology workflow capable of targeted quantification of AAS and structural elucidation for potential unknowns, allowing ions to be separated and characterized based on their rotationally averaged collision cross section (CCS). Chapter 1 provides a background of the basic principles of IMS and the different types of analytical methods used for doping analysis currently …

Global Upper Bounds For The Landau Equation Of Plasma Physics In The Very Soft Potentials Case, Caleb Solomon

Theses and Dissertations

This paper explores global upper bounds for solutions of the Landau equation in the soft potentials case (γ < −2). In particular, this paper explores the case of γ ∈ [−3,−2). Working with a classical solution to the Landau equation weighted by a cut-off function χ and using the Moser iteration, an upper bound for the L∞v norm of the solution to the Landau equation f is obtained proportianally to the L2 v norm of f with the assumptions of positive, essentially bounded coefficients. The supremum of f for t ∈ [0, T], x ∈ R3, v ∈ BR for some large radius R is shown to be bounded polynomially in R.

Analysis Of Steroid Hormone Isomers Using Ion Mobility-Mass Spectrometry, Shon Paul Neal

Theses and Dissertations

This dissertation presents a comprehensive study on the analysis of steroid hormone isomers using liquid chromatography-ion mobility-mass spectrometry (LC-IM-MS). The dissertation is divided into three main parts: the first part focuses on research using different drift gases and ion adducts to modify the mobility separations allowing for resolution between the isomers. The second part focuses on research exploring derivatization reactions that target structural differences between the steroid hormone isomers to amplify the differences and resolve the isomers in the ion mobility region. The final part covers a proposal on future study directions to include simultaneous derivatization reactions, mass spectrometry fragmentation, …

Assessing The Effect Of Atmospheric Turbulence On Long-Range Face Recognition Accuracy, Muskan Jain

Theses and Dissertations

Recent investigations have demonstrated that it might be challenging to identify faces in the images taken using a long-distance camera. A face seems blurry in these images because of the presence of atmospheric turbulence. To examine how atmospheric turbulence impacts face biometrics, we establish a simulated environment that exhibits different degrees of turbulence. We employed the Rytov Variance, which relies on the distance and refractive index, C2 n, to get various turbulence levels. We used the LRFID dataset to carry out the study, which is a collection of photos and videos taken in the field and in a controlled setting. …

Towards Privacy-Preserving Social Media Networks: Protecting The Facial Privacy Of Images Uploaded On Social Media, Ahsi Lo

Theses and Dissertations

Since the 2000s, social media has allowed individuals the ability to communicate online. As the popularity of social media increased, the sharing of information such as pictures increased as well. Recently, there have been privacy concerns about the information shared online such as cases where third parties were able to gain access to users’ information without being given explicit access through scraping or other means. When user images are scraped from social media, there is a risk that these individuals can be identified o✏ine. Bystanders, who may be captured in images also run this risk of identification. This research investigates …

1. Influence Of Metal Ions And Solvents On The Photo-Generation Of Reactive Oxygen Species In Mesoporous Silicate Embedded Porphyrins 2.Water-Soluble Rhodium(Iii) Porphyrin Complex For The Biological Inactivation Of Fentanyl, Hemant Pal

Theses and Dissertations

Porphyrins are differentiated π-conjugated compounds with unique photochemical and redox properties. The tetrapyrrole macrocycle core of porphyrins is extremely favorable for the complexation of metal ions, resulting in hybrid metal-organic molecules with good catalytic properties. Porphyrin-based systems are known for their oxidative properties and are frequently utilized as bio-mimicking catalysts and environmental remediation agents. My current research aims at both of these aspects. One of the most efficient methods to create photocatalytic systems with outstanding features and applicability is the use of porphyrins on supported solid materials. A series of novel mesoporous silicate-embedded metalloporphyrins were prepared via conjugation of novel …

Modeling And Simulation Of Ion-Induced Volume Phase Transitions In Chemically-Active Polyelectrolyte Gels, Bindi Mahesh Nagda

Theses and Dissertations

Ion-induced volume phase transitions in polyelectrolyte gels play an important role in physiological processes such as mucus storage and secretion in the gut, nerve tissue excitation, and DNA packaging. Biological experiments show that polyelectrolyte gels may swell or collapse rapidly due to changes in external conditions such as ionic composition. The volume phase transition is accompanied by a monovalent/ divalent ion exchange between the polymer network and the solvent that make up the gel. We propose a 2D computational method for simulating mucus swelling and deswelling with a two-fluid mixture model. The model includes electro-diffusive transport of ionic species, the …

A Comparison Of Automated Bolide Detection Methods, Maxine Thembi Khumalo

Theses and Dissertations

Bolide recording and analysis are crucial so meteoroid fragments can be found, a lightcurve analyzed, and its trajectory calculated. The Spalding Allsky Camera Network (SACN) generates videos and composite images of the night sky that are potential meteors based on changes in brightness. The best way to ensure quick identification is to automate the detection of bolides (and all meteors) using computational techniques. This project tested three algorithms to sort events between those with and without meteors - a Traditional Hough Detection Method, Convolutional Neural Network (CNN), and YOLOv5 against the previous technique from 2018 by Elena Botella. All the …

Water-Soluble Iron Porphyrin Complex For The Catalytic N-Dealkylation Of Fentanyl, Amanda Pitt

Theses and Dissertations

An increase in the misuse of opioids in the United States and the increasing potency of analogs necessitates novel treatments of opioid overdose. The chemical structure of synthetic opioids, such as fentanyl, carfentanil, and morphine possess a trialkyl amine functional group (-NR3) which makes for a promising target for potential catalysts. Iron (III)-tetrasulfonatophenyl porphyrin (complex 9) was synthesized as a potential catalyst for degradation of fentanyl. Complex 9a was prepared from the direct reaction of the free porphyrin and FeSO4. Complex 9b was prepared from the direct reaction of the free porphyrin and FeCl2 in refluxing DMF. The complexes were …

Propuesta De Un Modelo De Enseñanza En Las Matemáticas Enfocado En La Solución De Problemas En El Nivel Secundario En Puerto Rico, Carlos J. Colon Rivera

Theses and Dissertations

El propósito del estudio fue proponer un modelo educativo enfocado en la solución de problemas matemáticos en el nivel secundario, y se realizó la revisión sistemática para evaluarlo. El marco teórico incluyó teorías heurísticas y modelos educativos. La metodología de seis fases que se empleó en este estudio, incluyendo la formulación de preguntas investigativas, búsqueda de literatura, selección de investigaciones, levantamiento de información, análisis y resumen de resultados y exposición y discusión de estos. Se siguieron guías para revisiones sistemáticas y criterios de inclusión y exclusión para evaluar la efectividad de modelos didácticos en la disciplina de matemáticas con énfasis …

Popr: Probabilistic Offline Policy Ranking With Expert Data, Trevor F. Schwantes

Theses and Dissertations

While existing off-policy evaluation (OPE) methods typically estimate the value of a policy, in real-world applications, OPE is often used to compare and rank policies before deploying them in the real world. This is also known as the offline policy ranking problem. While one can rank the policies based on point estimates from OPE, it is beneficial to estimate the full distribution of outcomes for policy ranking and selection. This paper introduces Probabilistic Offline Policy Ranking that works with expert trajectories. It introduces rigorous statistical inference capabilities to offline evaluation, which facilitates probabilistic comparisons of candidate policies before they are …

Introducing Stochastic Time Delays In Gradient Optimization As A Method For Complex Loss Surface Navigation In High-Dimensional Settings, Eric Benson Manner

Theses and Dissertations

Time delays are an inherent part of real-world systems. Besides the apparent slowing of the system, these time delays often cause destabilization in otherwise stable systems, and perhaps even more unexpectedly, can stabilize an unstable system. Here, we propose the Stochastic Time-Delayed Adaptation as a method for improving optimization on certain high-dimensional surfaces, which simply wraps a known optimizer --such as the Adam optimizer-- and is able to add a variety of time-delays. We begin by exploring time delays on certain gradient-based optimization methods and their affect on the optimizer's convergence properties. These optimizers include the standard gradient descent method …

Zero And Few-Shot Concept Learning With Pre-Trained Embeddings, Jamison M. Moody

Theses and Dissertations

Neural networks typically struggle with reasoning tasks on out of domain data, something that humans can more easily adapt to. Humans come with prior knowledge of concepts and can segment their environment into building blocks (such as objects) that allow them to reason effectively in unfamiliar situations. Using this intuition, we train a network that utilizes fixed embeddings from the CLIP (Contrastive Language--Image Pre-training) model to do a simple task that the original CLIP model struggles with. The network learns concepts (such as "collide" and "avoid") in a supervised source domain in such a way that the network can adapt …

Bacterial-Mediated Photocatalytic Organic Oxidation, Peter J. Pellegrinelli

Theses and Dissertations

Bacteria, though well-known and widespread in scientific application, have plenty more opportunity to grow in the field of organic synthesis. The primary objective of this project was to apply the use of bioluminescent bacteria in an organic photoredox reaction intending to use the bacteria as a renewable source of light. This sustainable method, as opposed to high wattage bulbs, paves a green pathway for organic photocatalytic reactions. Using bioluminescent E. coli, the focus was on performing organic oxidation reactions with a recyclable photocatalyst. When using bacteria in conjunction with chemicals like nitromethane, it was an obstacle to keep the E. …

Rigorous Computation Of The Evans Function, Devin Mcghie

Theses and Dissertations

We develop computer-assisted methods of proof for rigorous computation of the Evans function in order to prove stability of traveling waves. We use the parameterization method, series solutions, and the Newton-Kantorovich Theorem to obtain precise, rigorous error bounds for the numerical solution of the ODE used in the construction of the Evans function. We demonstrate these methods on a scalar reaction-diffusion model and on the Gray-Scott model.