Digital Commons Network^™

Using The Schism Model And Hf Radar Data To Study Surface Currents In Texas Bays: A Case Study Of Sabine Lake (Sl) And Galveston Bay (Gb)., Cletus Ozoemena Ogbodo

Open Access Theses & Dissertations

Surface currents study provides invaluable understanding into the physical dynamics of oceans, bays, estuaries, and nearshore environments, offering critical insights about water movement and related coastal processes. These currents play a fundamental role in understanding the state of estuarine and marine systems, such as their effects on sediment transport, heat distribution and climate change, nutrient distribution, and pollutant dispersal. In addition, surface current data provides significant economic and ecological implications for coastal communities essential for managing resources effectively and ensuring the resilience of coastal regions against environmental and anthropogenic pressures. This study was driven by the need to address the …

Monitoring Of Laser Soldering Process In Hybrid Additive Manufacturing, Alexander P. Pustinger

Open Access Theses & Dissertations

Additive manufacturing (AM) has been a maturing technology that has expanded over the course of the last decade in major advancements especially in accessibility, process monitoring, modeling, and stock material design. As its industry use is growing, the demand for added improvements such as multi-functionality increases, such as with a hybrid system that allows for modification of printed parts with different electrical components like the Foundry Multi-3D system. The system's purpose is to create AM parts with multifunctional electrical components with the vision to expand to other areas of interest in manufacturing such as ISAM. This work explores the use …

Computational Investigation Of Boundary-Layer Transition Mechanisms In A Blunt Cone, Arturo Rodriguez

Open Access Theses & Dissertations

In this study, we have performed two-dimensional steady-state hypersonic CFD and one-and-two-dimensional steady-state heat conduction numerical simulations. We are using them to guide and study hypersonic boundary-layer transition ground testing physical experiments to be performed at Holloman High-Speed Test Track. We use surface heat transfer and fluid flow spot signatures to identify fluid flow regimes using laminar and turbulent numerical simulation solvers to understand boundary-layer transition thermocouple temperatures and fluid flow-forming structures. We have also analyzed the fluid flow in the geometries to be inviscid. We passed the CFD solution into the boundary-layer Harris code developed by NASA to explore …

Intrinsic, Doped And Alloyed Gallium Oxide Films For Optoelectronics, Francelia Sanchez Escobar

Open Access Theses & Dissertations

Due to the impressive advancement of present technology and increasing energy consumption, there is increasing demand for energy-efficient multifunctional devices based on low-cost, eco-friendly material systems. Gallium oxide (Ga2O3) is an emerging semiconductor with potential for the next generation of power electronics and optoelectronic devices due to its ultra-wide bandgap of 4.8 eV and high theoretical breakdown voltage of 8 MV/cm among other intrinsic properties. Some of the possible applications of β-Ga2O3 include ultra-violet (UV) solar blind photodetectors, field effect transistors, solar cells, and chemical sensors. However, to utilize its full potential, understanding the mechanistic aspects of thin film growth …

Enhanced Redox Storage And Diverse Intercalation In Layered Metal Organic Frameworks With A Staggered Stacking Mode, Satya Prakash Suman

Open Access Theses & Dissertations

Two-dimensional metal organic frameworks (2D MOFs) with honeycomb-like porous sheets are of growing interest for applications in electrochemical energy storage and electrocatalysis. Notably, 2D MOFs that host their porous sheets in eclipsed or slipped-parallel stacking modes possess continuous one-dimensional pores (1D) and have been widely studied. In contrast, related 2D MOFs with a staggered stacking mode have reduced porosity, are relatively rare, and are largely unexplored for applications. Here we report 2-fold enhanced redox storage and intercalation of diverse ions in a staggered-stacked, nonporous 2D MOF over its eclipsed-stacked, porous counterpart. Interestingly, both MOFs, despite undergoing similar ligand-centered redox processes, …

Tracking - Uh - Attention: Examining The Influence Of Filled Pauses During Speech Comprehension, Rachel Lynn Williams

Open Access Theses & Dissertations

In this study, we investigated the temporal dynamics of attention during comprehension and the subsequent effects of changes in attention on speech production manipulated via the filled pause uh. Participants orally described a series of pictures (pretest description phase), then listened to a short informational passage and answered comprehension questions about the passage, and then orally described another series of pictures (posttest description phase). Participants completed this twice: the first passage included a dative structure alternation, and the second passage included a passive structure alternation. For each passage, half of the participants heard a passage with filled pauses included (present) …

An Exploration Of K-3 Teachers’ Beliefs, Attitudes, And Instructional Technology Use Pre-, During, And Post-Covid-19, Patience Mensah-Bonsu Aggrey

Electronic Theses and Dissertations

This qualitative multiple case study explores kindergarten to third-grade teachers use of instructional technology across three different periods: pre-COVID-19, during COVID-19, and post-COVID-19. This research investigates teachers’ attitudes, the use of technological tools by teachers, and the internal (second order) and external (first order) barriers that informed their use of instructional technology before and during the COVID-19 pandemic and continue to influence their use in the post-pandemic phase. Data were collected through questionnaires, interviews, and checklists from eight kindergarten third-grade teachers using a qualitative multiple case study approach. The findings suggest that there was a shift in teachers’ instructional technology …

Demonstrating Feasibility Of Ultrasound-Sensitive Microbubbles Delivery To Treat Disruptions In The Blood Brain Barrier Endothelium, Rubens Jourdain

Theses and Dissertations

Vascular cognitive impairment and dementia (VCID) is one of the main causes of dementia. VCID is caused by age and other genetic factors that lead to disruptions in the blood brain barrier (BBB) and allow blood components to enter the brain. The currently available treatments of VCID include opening the BBB with high-frequency-ultrasound to deliver drugs to the brain. However, this only treats the already developed disease. Consequently, we developed a new drug delivery system whose goal is to restore the brain capillary endothelial cells (BCEC) lining the blood vessel. The objective of this study was to demonstrate the feasibility …

Synthesis Of Photocleavable Molecules For Neurological Applications, Nishal Madujith Egodawaththa Arachchilage Don

Theses and Dissertations

In recent biomedical research, the precise control of molecular dynamics through light activation has emerged as a powerful tool, particularly in the field of neurobiology. This approach involves the use of photocleavable cages or photoprotective groups (PPGs) that are chemically tethered to biologically active molecules such as neurotransmitters or calcium chelators. These cages remain inert until exposed to specific wavelengths of light, typically in the visible range, triggering the release of the active compound with high spatiotemporal precision.

For neurotransmitter systems, such as glutamate (Glu), which plays a critical role in synaptic transmission and memory formation, researchers have developed novel …

A Machine Learning Approach For Survival Analysis Of Transplanted Kidneys Based On Donors’ And Recipients’ Factors., Alain Edward Despeignes

Theses and Dissertations

Over seven thousand people on average die each year in the United States waiting for an organ transplant due to the shortage of donated organs. With this alarming concern, efforts from the health organizations like the United Network Organ Sharing (UNOS) and government officials have considered avenues to remedy this distress, one of which is to investigate the characteristics among donors and recipients that affects the longevity of donated organs. The goal of this project is to investigate the survival time of transplanted kidneys from 1987 to 2018 with regards to the donors’ and the recipients’ characteristics including gender, ethnicity, …

Novel, Ultra-Fast Electrochemical Sensors For The Enhanced Detection Of Neurotransmitters And Toxic Heavy Metals In Aqueous Solutions, Noel Manring

Theses and Dissertations

Neurodegenerative diseases (NDDs) are a growing global health concern, affecting millions of people worldwide. NDDs arise from the progressive loss of neuronal cell function, ultimately leading to cell death. Abnormal levels of neurotransmitters, the chemical messengers in the brain, have also been linked to NDDs. Despite various treatments and medications aimed at alleviating physical and mental symptoms, there is currently no cure or means to halt disease progression. While the exact pathogenesis of NDDs remain poorly understood, cognitive decline is largely attributed to brain volume reduction, particularly in the hippocampus. Clinical studies suggest that environmental factors, such as exposure to …

Adsorption Of Harmful Algal Bloom Toxins Using Biochar, Cadianne Chambers

Theses and Dissertations

Harmful Algal Bloom (HAB) events involve the proliferation of microalgae which discharge lethal toxins into fresh and brackish water bodies due to anthropogenic and climatic activities. Common examples of HABs include causative organisms such as Cyanobacteria, Pyrodinium bahamense and more. These genera are known to release potent toxins including Microcystins, and Saxitoxins, respectively, which can seriously endanger human and marine health. Ingestion of these toxins can result in several health problems, such as nausea, vomiting, gastroenteritis, skin irritation, liver damage, paralysis, and respiratory arrest. The Great Lakes, Gulf of Maine, Florida’s coasts, Lake Erie, and Lake Okeechobee have all been …

Heterogeneous Collaborative Robotics: Multi-Robot Navigation In Dynamic Environments, Tyler Nicholas Raettig

Theses and Dissertations

Abstract: The challenges of multi-robot navigation in dynamic environments, focusing on uncertainties in obstacle complexities, partial observation, and the transition of policies from simulations to the real world. The proposed approach utilizes a deep reinforcement learning (DRL) framework enabling a Light Detection and Ranging (LiDAR)-equipped robot to communicate with a camera-equipped robot to achieve optimal paths despite their different sensors. The key contributions include the development of a cooperative architecture for information exchange between robots, a DRL-based framework for learning navigation policies, and a training mechanism based on dynamic randomization for enhanced real-world adaptability. Experimental validation using Gazebo simulations demonstrates …

Advancing Biofabrication Methodologies To Develop Biomimetic Tissue Scaffolds For Musculoskeletal Applications, Nashaita Yezdi Patrawalla

Theses and Dissertations

Musculoskeletal injuries impose a significant global burden, affecting millions and generating an economic toll exceeding $14 billion. Tissue engineering has gained traction as a promising strategy offering potential for functional restoration of damaged musculoskeletal tissues. This research aims to advance biofabrication techniques for generation of biomimetic tissue scaffolds, by optimizing scaffold design and modulating fabrication process parameters to generate scaffolds for musculoskeletal regeneration with application-specific tailored properties. In this realm, collagen-based biomaterials have been extensively investigated for tendon and ligamentous applications, and in combination with bioceramics incorporated into the collagen framework to produce composite scaffolds that better recapitulate the native …

Theoretical Advancements In Hawkes Processes And Their Practical Applications, Xi Zhang

Theses and Dissertations

Hawkes self-exciting point processes have been widely used in fields such as seismology, finance and social media analysis. Despite decades of research focusing on these processes, several key aspects remain under-explored. These include broadly applicable methods for model evaluation and selection, intuitive nonparametric inference approaches akin to kernel density estimation for probability density functions, and strategies to enhance the performance of generative point process models in predictive tasks. In this dissertation, first, we extend the time-rescaling theorem, which is traditionally limited to non-terminating processes with complete observations, to accommodate terminating processes and incomplete observations as well. This extension allows for …

Impact Of State-Level Family Policies On Female Labor Force Participation And Entrepreneurship, Kathryn Staczek Rudloff

Theses and Dissertations

This dissertation aims to investigate the impact of state-level family policies on women's participation in the labor force in the United States, focusing specifically on the rise of self-employment and solopreneurship among women. The research seeks to answer the following question: "How do family policies at the state level impact participation of American women in the labor force?"

The study utilized a convergent parallel mixed-methods design. A composite index of state level family policies was created to conduct cross-sectional exploratory data analysis of female labor force participation. Additionally, a qualitative phenomenological study of solopreneurs provided a deeper understanding of the …

Decoding Neural Networks: An Information-Theoretic Guide To Interpretability, Error Analysis And Efficiency, Mackenzie J. Meni

Theses and Dissertations

This dissertation addresses critical challenges in neural network design by leveraging entropy-based techniques to improve model efficiency, interpretability, and bias reduction. Focusing on the unique demands of computer vision applications, particularly object detection and classification for real-time systems, this work introduces a series of innovative methods centered on information theory. At the core of these methods is the Probabilistic Explanations of Entropic Knowledge (PEEK) framework, a tool developed to analyze and visualize entropy distributions across feature maps. PEEK offers insights into information flow within neural networks, making it possible to pinpoint layers that contribute meaningfully to decision-making or identify those …

Improving Robustness Of Learning-Based Approaches In Autonomous Systems And Engineering Education, Godwyll Aikins

Theses and Dissertations

This dissertation advances the development of robust learning-based approaches across two complementary domains: engineering education and autonomous systems. Through four studies, this research addresses critical challenges in preparing data-proficient engineers and developing reliable autonomous systems that can operate under uncertainty and incomplete information. The engineering education study examines how mechanical and aerospace engineering undergraduates conceptualize and develop data proficiency skills essential for modern engineering practice. Through interviews with 27 students, the research employs the How People Learn framework to analyze student perspectives on information literacy, data interpretation, and computational thinking. The findings inform pedagogical strategies for developing data proficiency in …

Breaking The Procrastination Barrier, Bianca Ebanks

Theses and Dissertations

Procrastination is a common barrier to productivity, impacting individuals' ability to achieve goals, especially in academic and professional settings. This study investigates a mixed-methods online intervention combining Behavioral Analysis (BA) principles with mindfulness exercises to reduce procrastination. The aim was to develop a human-centered, personalized intervention that utilizes behavioral reminders and mindfulness techniques to address procrastination in 43 participants. Participants' procrastination levels were assessed using the Irrational Procrastination Scale (IPS), and interventions were tailored based on individual procrastination tendencies. Reminders were sent via email or text, with timing adjusted to participants’ specific needs. The intervention also included mindfulness exercises designed …

Assessing General Propulsion Architectures For Fast Transit Times To Mars For Crewed Missions, Vivek Bhatt

Doctoral Dissertations and Master's Theses

As NASA and commercial contractors, such as SpaceX, continue to develop their programs with Artemis and Starship, respectively, it is becoming more and more apparent that the program developments are ultimately for finding a way to put humans onto Mars. However, when we approach the current timeline of going to Mars, it usually involves a 6-9 month one way trip. Due to this, human spaceflight to Mars becomes more dangerous as exposure to affects such as solar radiation, long exposure to low gravity fields, and isolation. These are some of the many hazards that come with interplanetary space travel for …

Transplantation And Immortality: A Selective History Of Boston University’S Center For Health Law, Ethics & Human Rights, George J. Annas

Faculty Scholarship

The celebration of the anniversary of the Center for Health Law, Ethics & Human Rights (the “Center”) provides an opportunity to reflect on what defines the field of health law, as well as its conjoined twins of bioethics and human rights. The related fields are vast, and the subjects they encompass are ever-expanding. It is probably impossible to lay out a summary that does justice to their expansive, interdisciplinary scope. Instead, my discussion of the Center examines a subject that barely existed when the Center was formed in 19581 and that continues to make headlines more than sixty–six years later …

Designing A Robust Lab Scale Electrocoagulation Reactor For Removal Of Micro- And Nanoplastics From Drinking Water, Emmanuel Louis Aduhene

All Graduate Reports and Creative Projects, Fall 2023 to Present

The widespread occurrence of micro and nanoplastics in drinking water sources could cause serious public health issues. These plastics particles, products of industrial operations and weathering of larger plastics, can interact with other contaminants in the environment, leading to more severe environmental pollution. Present drinking water treatment technologies were designed to remove suspended colloids. However, due to the distinct chemical and physical properties of micro and nanoplastics from conventional colloids, it is challenging for traditional chemical coagulation/flocculation/sedimentation process to achieve satisfying removal performance. This report investigates a design of a lab-scale electrocoagulation reactor for the removal of nanoplastics from drinking …

Quantitative Analysis Of Protective Effect Of Resveratrol Against Nanoplastic-Induced Oxidative Stress, Bryan Gustafson

All Graduate Reports and Creative Projects, Fall 2023 to Present

Nanoplastics and microplastics are a growing ecological and health concern due to their widespread prevalence. The effects of these microscopic particles in biological systems primarily relate to their potential to produce reactive oxygen species and interactive effects with other cytotoxic agents. Of particular interest in this work is the effect on mammalian intestinal cells, due to the regular unintentional ingestion of micro- and nanoplastics in the normal western diet. In this study, Caco-2 cells were cultured and exposed to polystyrene particles in vitro as a simple model of the human digestive endothelium.

Resveratrol, a naturally occurring polyphenolic compound, has been …

Professional Portfolio: Assessment Of And Strategies For Improving A Middle School Student’S Mathematics Performance, Gwenyth O. Falck

All Graduate Reports and Creative Projects, Fall 2023 to Present

This project explores strategies to help secondary students with disabilities improve their mathematics performance. With eighth-grade math scores trending downward and algebra serving as a critical gateway to higher education, target interventions are needed. The literature review highlights two main instructional methods: the Explicit Inquiry Routine (EIR) and the Concrete-Representational-Abstract Integration (CRA-I). Both incorporate physical and virtual manipulatives. These approaches have been shown to help students grasp algebraic concepts, retain what they have learned and apply the skills to new types of problems.

In addition to the research review, this paper includes assessment and intervention reports for a seventh-grade student …

Developing A Bilingual Health Education Program To Identify And Address Healthcare Misinformation In A Border Community, Sara Mansour, Nathan Holland, Sergio Saucedo, Amadeus Ramirez, Mariela Lane, Joshua Salisbury, Komal Marwaha, Lorena Fernandez, Jesse Allen, Ricardo Belmares

School of Medicine Publications

El Paso Health Education and Awareness Team (EP-HEAT®) is a bilingual program focused on increasing health awareness and dispelling health-related misinformation in the U.S.-Mexico border region. EP-HEAT® consists of students, faculty, staff, and Promotoras. The primary objective of EP-HEAT® is to empower the community with healthcare resources in a culturally acceptable way. EP-HEAT® established the bilingual “In the Hot Seat with EP-HEAT®: Dispelling Myths in Healthcare” series commonly referred to as Myth Busters events. Community members were surveyed following the events. Our results showed the majority of EP-HEAT® event attendees identified as Hispanic and were older than 46 years …

Impact Of Delphi-Developed Rubrics On Rater Consistency In 14 Cfr 141 Flight Training Assessment Environments, Lewis Robert James Archer

Theses and Dissertations

Pilot schools operating in accordance with 14 CFR 141 provide a substantial supply of pilots to the aviation industry. Recent high industry demand for pilots has created turnover among the flight instructor workforce, often considered an entry-level position used by aspiring aviators to build flight experience. This in turn means that check instructors, evaluators who are often selected from the more senior flight instructor population at a pilot school, are generally less experienced than in the past. Anecdotal evidence suggests that there is low consistency among these check instructors when conducting performance-based assessments. This study sought to determine the existing …

The Catalytic Conversion Of Corn Stover Sugars Into Lactic Acid, Ahmed Essam

Theses and Dissertations

The rising global demand for addressing global warming necessitates the development of renewable-based alternatives to current fossil fuel-based chemicals and fuels. Lignocellulosic biomass is the most abundant energy source following fossil fuels. As a result, agricultural residues such as corn stover have attracted substantial interest for utilization as a potential feedstock for renewable chemicals.Previous research work at the University of North Dakota showed promising results in converting corn stover sugars into chemical building blocks. The most crucial of these chemicals is lactic acid, which can be used in multiple applications including food, pharmaceuticals, and biodegradable plastics. Traditionally, lactic acid is …

Exploring The Potential Of Hybrid Wind-Solar Energy Systems For Residential Applications In North Dakota, Toluwase Testimony Omojiba

Theses and Dissertations

North Dakota's high residential energy consumption, driven by extreme weather, is largely met by fossil fuels, contributing significantly to CO₂ emissions. This study evaluates the technical performance, environmental benefits, and economic viability of hybrid wind-solar-energy systems for residential applications in the state.

Using HOMER modeling, two scenarios were analyzed: homes using a combination of utility gas and electricity, and homes relying solely on electricity. Simulations for Grand Forks, Bismarck, and Dickinson showed that hybrid systems reliably met residential energy demand, covering 100% of the annual load in the gas-electric scenario across all locations. In the all-electric scenario, systems achieved at …

An Analysis Of Curricular Complexity Patterns In Undergraduate Mechanical Engineering Programs Using Federally Reported Data, Shane Schellpfeffer

Theses and Dissertations

With the recent development of curricular analytics tools designed to quantify the structure of a curriculum (Heileman, Abdallah, et al., 2018), some institutions of higher education are examining their curricula to find ways that these pathways to graduation can be improved (McMurtrie, 2021). The tools used to analyze curricula were created to address an issue of importance in the field of undergraduate engineering, that issue being the decreasing enrollment trend over the past two decades. The decrease in undergraduate engineering graduates in programs across the United States led to conversations in both academia and industry regarding potential solutions for this …

Observational Analyses Of Aerosol Radiative Impacts On Weather And Climate Scales, Blake Thomas Sorenson

Theses and Dissertations

With the enhanced Arctic warming and sea ice melting in recent decades, this study seeks to expand our understanding of how atmospheric aerosols affect the Arctic radiative budget, on both weather and climate scales. On climate scales, the study of the impact of atmospheric aerosols on Arctic radiative budget, through observation-based methods, remains challenging due to the complicated surface conditions including sea ice, open oceans, and land surfaces. Using satellite observations from the Ozone Monitoring Instrument (OMI), the Moderate Resolution Imaging Spectroradiometer (MODIS), the Cloud and the Earth Radiant Energy System (CERES), and the Special Sensor Microwave Imager / Sounder …