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Uniquely Tailored Ionic Materials For Implementation In Energy, Imagining, And Antibacterial Applications, Amanda Jalihal Dec 2023

Uniquely Tailored Ionic Materials For Implementation In Energy, Imagining, And Antibacterial Applications, Amanda Jalihal

Theses and Dissertations

In this dissertation, the novel class of ionic materials is explored. Ionic materials are easily tuned and tailored to fit a wide variety of applications. The synthesis of ionic materials is extremely simple and prompt. Briefly, two ionic moieties are joined electrostatically through a double displacement resulting in a new compound without complicated synthesis. This process leads to a close proximity of the ions which allows for enhancement of the FRET mechanism between a fluorophore and chromophore. A potential application of a FRET active ionic material is explored as a photosensitizer using IR820 and Nile Blue A. The ionic material, …


Economic Governance And Violence: A Cross-National Analysis, Steven Mccain Dec 2023

Economic Governance And Violence: A Cross-National Analysis, Steven Mccain

Theses and Dissertations

Understanding how economic governance influences routine activities is crucial within the field of criminology to better understand how grounds for violence emerge. Literature of cross-national studies concerning the effects of economic governance has recently developed to study its relationship with violence, specifically homicide. However, there is a deficit of frameworks related to criminological theory in this literature. Using a routine activity framework, the current dissertation seeks understand how different degrees of economic governance in general and, more specifically, the five areas of economic governance – size of government, legal system and property rights, sound money, freedom to international trade, and …


A Hybrid Cognitive Model For Machine Agents In Project And Action Teams, Joshua A. Lapso Dec 2023

A Hybrid Cognitive Model For Machine Agents In Project And Action Teams, Joshua A. Lapso

Theses and Dissertations

High performing human teams transcend complex domain uncertainty by achieving an emergent state of shared cognition, in which knowledge is organized, represented, and distributed to team members for rapid execution. However, this requires that individuals emit perceivable qualities upon which other members can make inferences about intent. In pursuit of future human and machine team studies, this research presents a hybrid cognitive model for machine agents in fully cooperative and semi-cooperative action and project teams. The hybrid cognitive model unifies the characteristics of the shared mental model and transactive memory system. The resultant model facilitates anytime selection over the two …


Waterbody Size Influences Chemical And Community Characteristics Of North Dakota Prairie Wetlands And Lakes, Julia Renee Hampton Dec 2023

Waterbody Size Influences Chemical And Community Characteristics Of North Dakota Prairie Wetlands And Lakes, Julia Renee Hampton

Theses and Dissertations

The Prairie Pothole Region (PPR) of North America is home to dynamic glacier-formed lakes and wetlands that range in size from small intermittent wetlands to large permanently filled basins. Predicting water-related shifts in environmental conditions and biological community responses within these systems has been challenging due to non-linear, scale-specific changes. Furthermore, landscape-level changes in the quantity and distribution of surface water are becoming more frequent. This thesis contributes to our understanding of how waterbody size, and potential size fluctuations, influence chemical and community dynamics of complex PPR glacial lakes and wetlands. We paired remote sensing and discontinuity methods with US …


Process-Structure-Property Relationships Of Nanofibers For Biomedical Applications, Dipasree Bhowmick Dec 2023

Process-Structure-Property Relationships Of Nanofibers For Biomedical Applications, Dipasree Bhowmick

Theses and Dissertations

This thesis explores the fabrication, characterization, and applications of nanofiber membranes utilizing Forcespinning® technology. Two distinct nanofiber systems were developed and evaluated, one focusing on pH-responsive Eudragit-baicalin loaded nanofibrous membranes for wound healing and the second one on thermo-responsive nanofiber-hydrogel (PNIPAAm) systems for biosensing applications, specifically dopamine detection. In the first project, nanofiber membranes loaded with Eudragit and baicalin demonstrated superior antibacterial properties against both gram-negative (E. coli) and gram-positive (B. meg) bacteria. Additionally, these membranes exhibited antioxidant properties and enhanced cell proliferation of 3TT cells, making them promising candidates for wound healing dressings. In the second project, a …


Monitoring The Effectiveness Of Wildlife Exits And Bobcat Use Along A South Texas Highway, Jamie E. Langbein Dec 2023

Monitoring The Effectiveness Of Wildlife Exits And Bobcat Use Along A South Texas Highway, Jamie E. Langbein

Theses and Dissertations

Roadside exclusion fencing is commonly used to mitigate wildlife road mortalities and property damages caused by wildlife-vehicle collisions. A potential consequence is that animals may become trapped on the road by fencing. On State Highway 100 in South Texas, the Texas Department of Transportation installed ten wildlife exits (WE) allowing animals to exit the roadway through a modified opening in the fence. However, some individuals used the WE to access the roadway. In this study, a new design was implemented, with narrower openings, a ramp and a clear plastic one-way door. While the updated design prevented road access for wildlife, …


Examining Social Factors Influencing Latino Students' Academic Learning In Rio Grande Valley Via A Quantitative Design, David T. Smith Dec 2023

Examining Social Factors Influencing Latino Students' Academic Learning In Rio Grande Valley Via A Quantitative Design, David T. Smith

Theses and Dissertations

This research study aimed to examine the social factors that could influence the academic learning experiences of Latino college students. Hispanic students are pursuing post-secondary degrees at a higher rate than in previous years. Many Hispanics represent their respective family members as the first members of their respective families to attend college (Trevino & DeFreitas, 2014). The academic achievement of Latino college students is becoming a major concern in the United States due to their growing population and special needs (Trevino & DeFreitas, 2014).

It is imperative to examine the social factors that could affect the academic learning experiences of …


Overexpression Of Ubtf Correlates With Aggressive Phenotypes Of Prostate Cancer Cells, Guillermo Andres Saldana Dec 2023

Overexpression Of Ubtf Correlates With Aggressive Phenotypes Of Prostate Cancer Cells, Guillermo Andres Saldana

Theses and Dissertations

Prostate cancer (PrCa) is one of the most common malignancies in men globally and the second leading cause of cancer associated deaths in developed countries. Accumulating evidence have demonstrated involvement of various molecular and cellular factors in the development, progression and chemoresistance of PrCa and many of them were successfully established as potential molecular targets for therapy. Despite these advancements, the underlying mechanisms of PrCa occurrence is still unclear, which limits the diagnosis and therapy. Therefore, it is an urgent need to discover potential molecular targets which can be used in rational design of new strategies for the prevention and …


Aedes Aegypti Host Preference On Canines Versus Human Volatile Skin Compounds, Melissa Bernadette Rosalez Dec 2023

Aedes Aegypti Host Preference On Canines Versus Human Volatile Skin Compounds, Melissa Bernadette Rosalez

Theses and Dissertations

It is critical to understand how Aedes aegypti mosquitoes detect hosts through cues such as volatile skin compounds. In South Texas, evidence suggests that this mosquito is showing a feeding preference for canines over humans. This shift may impact the transmission of Dirofilaria immitis, canine heart worms, in local dog populations. Our study is set to explore Ae. Aegypti attraction to hosts using canine and human volatile compounds. Volatile skin compounds will be collected using a volatile collection system. Compounds will be analyzed using gas chromatography/mass spectrometry. It is anticipated that the main volatile skin compounds amongst humans are nonanal, …


Growth Rates, Morphology, And Potential For Mariculture Of The Southern Population Of Crassostrea Virginica In The Lower Laguna Madre, Texas, Jerad Lee Fuelling Dec 2023

Growth Rates, Morphology, And Potential For Mariculture Of The Southern Population Of Crassostrea Virginica In The Lower Laguna Madre, Texas, Jerad Lee Fuelling

Theses and Dissertations

The Eastern Oyster also known as Crassostrea virginica, is an important resource here in the United States. Historically, this species has been overfished, poorly managed, and plagued by disease. Oyster mariculture is a growing industry here in the United States and is a sustainable solution to producing oysters. Texas has become the last coastal state to legalize oyster mariculture which means there is now a vast coastline with many unique bay systems that are open to this industry. One bay system that is particularly unique is the Lower Laguna Madre which is a hypersaline lagoon. Little is known about …


Electrolysis Degradation Of Cyanuric Acid In Wastewater At Cu/Go Cathodes, Chioma Chinwe Nwakanobi Dec 2023

Electrolysis Degradation Of Cyanuric Acid In Wastewater At Cu/Go Cathodes, Chioma Chinwe Nwakanobi

Theses and Dissertations

This work evaluates the development of electrochemical processes for the oxidative degradation of persistent organic chemicals in waste waters, specifically the oxidation of cyanuric acid in the presence of NaCl at Cu/GO cathodes and Ti anodes. The experiment used a graphene oxide doped copper mesh cathode to examine different concentrations of cyanuric acid (30 mg/L, 40 mg/L, and 50 mg/L) and various concentrations of NaCl electrolyte (0.007mol/L, 0.03mol/L, 0.07mol/L, 0.1mol/L, and 0.2mol/L). In addition, the effect of pH (2, 4, 6, and 8), and applied current (0.200A, 0.150A and 0.100A) were studied. The Cu/GO electrode played a central role in …


Intellibeehive, Christian Ivan Narcia-Macias Dec 2023

Intellibeehive, Christian Ivan Narcia-Macias

Theses and Dissertations

Utilizing computer vision and the latest technological advancements, in this study, we developed a honey bee monitoring system that aims to enhance our understanding of Colony Collapse Disorder, honey bee behavior, population decline, and overall hive health. The system is positioned at the hive entrance providing real-time data, enabling beekeepers to closely monitor the hive's activity and health through an account-based website. Using machine learning, our monitoring system can accurately track honey bees, monitor pollen-gathering activity, and detect Varroa mites, all without causing any disruption to the honey bees. Moreover, we have ensured that the development of this monitoring system …


Robust And Uncertainty-Aware Image Classification Using Bayesian Vision Transformer Model, Fazlur Rahman Bin Karim Dec 2023

Robust And Uncertainty-Aware Image Classification Using Bayesian Vision Transformer Model, Fazlur Rahman Bin Karim

Theses and Dissertations

Transformer Neural Networks have emerged as the predominant architecture for addressing a wide range of Natural Language Processing (NLP) applications such as machine translation, speech recognition, sentiment analysis, text anomaly detection, etc. This noteworthy achievement of Transformer Neural Networks in the NLP field has sparked a growing interest in integrating and utilizing Transformer models in computer vision tasks. The Vision Transformer (ViT) model efficiently captures long-range dependencies by employing a self-attention mechanism to transform different image data into meaningful, significant representations. Recently, the Vision Transformer (ViT) has exhibited incredible performance in solving image classification problems by utilizing ViT models, thereby …


Using Statistical Clustering Of Trajectory Data To Support Analysis Of Subject Movement In A Virtual Environment, Martín Alejandro Galicia Avila Dec 2023

Using Statistical Clustering Of Trajectory Data To Support Analysis Of Subject Movement In A Virtual Environment, Martín Alejandro Galicia Avila

Theses and Dissertations

The rising use of virtual reality software requires new methods of spatiotemporal analysis to enhance the user experience. This investigation is focused on forming clusters from spatiotemporal trajectories within a virtual environment and analyzing them in search of human immersion and behavior insights. The cluster centroids are plotted and analyzed to identify associations with the trajectories and user demographics.


Gaze Tracking Embedded Collaborative Robots For Automated Metrology And Reverse Engineering, Sachithra H. Karunathilake Dec 2023

Gaze Tracking Embedded Collaborative Robots For Automated Metrology And Reverse Engineering, Sachithra H. Karunathilake

Theses and Dissertations

Conventional geometric metrology, or three-dimensional (3D) scanning, and reverse engineering heavily rely on the experience of the operators. With an increasing need for automation, robot arms have been adopted for this task. However, due to the large variety of parts and designs, automated path planning could provide a scanning solution that may overlook the critical area, which could potentially deteriorate the scan results. This study explores the integration of collaborative robotics (cobots) with eye tracking technology to improve the autonomous 3D scanning process. The primary objective of this study is to enhance the accuracy and efficiency of cobots in …


Rhythmic Ritual: Hand Papermaking As A Transformative Process, Keatan Mckeever Dec 2023

Rhythmic Ritual: Hand Papermaking As A Transformative Process, Keatan Mckeever

Theses and Dissertations

This thesis is an exploration of the transformative processes of hand papermaking, both personally and materially, through various artworks situated between two- and three-dimensional forms. The conceptual motivations supporting my practice are informed by intuition, locally sourced materials, human connection, material structure, and low-tech approaches to the papermaking process. In the first portion of this thesis, I discuss how I chose paper as my artistic medium, and the transformational process of hand papermaking through a historical lens. The second half follows the experimentation and limitations that informed my practice, the content of my work regarding material and structural qualities, and …


An Automatic Solver For Optimal Control Problems, Marcel Efren Benitez Dec 2023

An Automatic Solver For Optimal Control Problems, Marcel Efren Benitez

Theses and Dissertations

Optimal control theory is a study that is used to find a control for a dynamical system over a period of time such that a objection function is optimized. In this study we will be looking at optimal control problems for ordinary differential equations or ODEs and see that we can use an automatic solver using the forward-backward sweep using Matlab to solve for them from an 1 dimension to bounded cases and to nth dimension cases.


Effects Of Short-Term Pesticides Exposure On Swimming Behavior, Tissue Morphology, Oxidative-Nitrative Stress, Antioxidant Expression, And Cellular Apoptosis In Kidneys Of Goldfish, Esmirna Cantú Dec 2023

Effects Of Short-Term Pesticides Exposure On Swimming Behavior, Tissue Morphology, Oxidative-Nitrative Stress, Antioxidant Expression, And Cellular Apoptosis In Kidneys Of Goldfish, Esmirna Cantú

Theses and Dissertations

The prevalence of pesticides in the aquatic environment continues to increase due to anthropogenic activities and poses a threat to aquatic organisms. The aim of this study was to determine the short-term exposure (one-week) of pesticide mixtures (metolachlor, linuron, isoproturon, tebucanazole, alconifen, atrazine, pendimethalin; azinphos-methyl) on swimming behaviors, kidney morphology, and expression of nitrotyrosine protein (NTP), dinitrophenyl protein (DNP), superoxide dismutase (SOD), catalase (CAT), renin, and cellular apoptosis in goldfish (Carassius auratus). Results indicated that both low- and high-dose pesticide mixtures decreased the distance swimming behavior. Histological analysis showed pesticide exposure alters kidney morphology. DNP, NTP, and renin expressions, and …


The Impacts Of Caregiving And Social Support On Stress For Multiple Sclerosis: A Study On Informal Caregivers, Jacqueline Mercado Dec 2023

The Impacts Of Caregiving And Social Support On Stress For Multiple Sclerosis: A Study On Informal Caregivers, Jacqueline Mercado

Theses and Dissertations

The purpose of the present quantitative study was to gain an increased understanding of the impacts of caregiving and social support on stress for unpaid informal caregivers of persons with Multiple Sclerosis. Caregiving for MS can be rewarding yet stressful. Informal caregivers are the primary source of ongoing home care for family members or friends with MS. Due to the complexity of care, caregivers are especially vulnerable to higher strain as they often feel unprepared for this role. This study examined perceived social support and demographic variables on caregivers' stress to gain insight into mediating caregiver psychosocial challenges. …


Examining Factors Among People With Opioid Use Disorder And Comorbid Mental Health Disorders, Tori Denae Livingston Dec 2023

Examining Factors Among People With Opioid Use Disorder And Comorbid Mental Health Disorders, Tori Denae Livingston

Theses and Dissertations

Opioid use disorder (OUD) affects over two million Americans, and over 42,000 Americans perished of opioid overdoses in 2016 (Volkow et al., 2019). During the initial years of the opioid crisis, overdose deaths were primarily attributed to prescription analgesics, heroin, and synthetic opioids. However, it was illicit prescription opioid painkiller use that ranked highest in terms of fatalities (Volkow et al., 2019). The increasing prevalence of opioid use among individuals with mental health disorders is in stark contrast to the ongoing opioid crisis (Prince, 2019). Additionally, there is evidence that individuals undergoing substance use treatment and concurrently suffering from a …


Being A Trafficked Teacher: An Asiancrit Autoethnography Exploring The Exploitation Of Filipino Migrant Teachers In Louisiana, Christopher R. Jose Dec 2023

Being A Trafficked Teacher: An Asiancrit Autoethnography Exploring The Exploitation Of Filipino Migrant Teachers In Louisiana, Christopher R. Jose

Theses and Dissertations

The purpose of this autoethnographic study is to critically explore the lived curriculum of Filipino migrant teachers trafficked by a Louisiana school district using the theoretical lens of AsianCrit. Using the different tenets of AsianCrit, this study wrestles with the injustices of this lived curriculum as connected to a broader set of hegemonic curricular experiences and demonstrates the ways such injustice still permeates the lived curriculum of migrant teachers. It explores its discussion on critical race theory in education, migrant teachers and human trafficking in the United States. This study shares the effects of human trafficking of teachers and the …


Chemical Investigation Of Dichloromethane Extract Of Aloe Vera Peels: An Agricultural Waste, Nazmul Huda Dec 2023

Chemical Investigation Of Dichloromethane Extract Of Aloe Vera Peels: An Agricultural Waste, Nazmul Huda

Theses and Dissertations

Aloe barbadensis Miller, commonly called Aloe Vera, is a widely popular succulent plant species cultivated across subtropical regions worldwide from India to the Tex-Mex border. Besides its historical uses, Aloe juice has garnered attention as a potential remedy for various ailments, particularly in treating various skin conditions and facilitating wound recovery, including obesity, diabetes, hepatitis, Crohn's disease, and ulcerative colitis. Regrettably, the agricultural practice following sap extraction involves discarding Aloe vera peels, constituting agricultural waste. As part of our continuous research on extraction, isolation, separation, and spectral characterization of value-added chemicals present in waste botanicals herein, …


Age-Related Oligodendrocyte Lineage And Learning Abnormalities Driven By Nf1 Mutation In Mice, Saul Lopez Dec 2023

Age-Related Oligodendrocyte Lineage And Learning Abnormalities Driven By Nf1 Mutation In Mice, Saul Lopez

Theses and Dissertations

Neurofibromatosis Type 1 (NF1) is an autosomal dominant disease caused by mutations in the NF1 gene, on chromosome 17. NF1 patients suffer from a number of neurological issues including learning deficits and increased risk of age-related dementia. Additionally, NF1 patients present with multiple white matter and myelin abnormalities. Whether and how myelin abnormalities impact learning in NF1 is not known; therefore, we aimed to gain insights on potential links between Nf1 mutation and learning issues Unpublished data indicate that NF1 female-but not male- mice with Nf1+/- germline mutation show defects in a myelin-regulated learning/memory test (the complex wheel; CW) at …


Human-Centric Smart Cities: A Digital Twin-Oriented Design Of Interactive Autonomous Vehicles, Oscar G. De Leon-Vazquez Dec 2023

Human-Centric Smart Cities: A Digital Twin-Oriented Design Of Interactive Autonomous Vehicles, Oscar G. De Leon-Vazquez

Theses and Dissertations

Autonomous vehicle (AV) technology is introduced as a solution to improve transportation safety by eliminating traffic accidents caused by human error, which is the leading cause of 90% of accidents. One key feature of AVs is sensing and perceiving their surrounding environment through processing observations collected from the environment. The perception system is essential for an AV to make informed decisions and safely navigate the environment. This study presents an image semantic segmentation algorithm developed in the area of computer vision to improve AV perception. The U-Net-based algorithm is trained and validated using a synthetically generated dataset in a simulation …


The Private Pilot Check Ride: Applying The Spacing Effect Theory To Predict Time To Proficiency For The Practical Test, Michael Scott Harwin Dec 2023

The Private Pilot Check Ride: Applying The Spacing Effect Theory To Predict Time To Proficiency For The Practical Test, Michael Scott Harwin

Theses and Dissertations

This study examined the relationship between a set of targeted factors and the total flight time students needed to become ready to take the private pilot check ride. The study was grounded in Ebbinghaus’s (1885/1913/2013) forgetting curve theory and spacing effect, and Ausubel’s (1963) theory of meaningful learning. The research factors included (a) training time to proficiency, which represented the number of training days needed to become check-ride ready; (b) flight training program (Part 61 vs. Part 141); (c) organization offering the training program (2- or 4-year college/university vs. FBO); (d) scheduling policy (mandated vs. student-driven); and demographical variables, which …


Climate Change And The Shifting Geography Of Coral-Reef Development, Victor Rodriguez-Ruano Dec 2023

Climate Change And The Shifting Geography Of Coral-Reef Development, Victor Rodriguez-Ruano

Theses and Dissertations

Coral-reef development is modulated by growth processes that deposit calcium carbonate onto the reef, such as calcification, and destructive processes that remove calcium carbonate from the reef, such as bioerosion. Wherever calcification rates exceed bioerosion rates, there is a net accretion of the reef through time, but where bioerosion rates exceed calcification rates, there is a net destruction of the reef through time. A reef’s framework is the legacy of the interaction of these processes throughout a reef’s history. Studying the fossil frameworks of reefs can shed light on the environmental factors that have controlled reef development in the past, …


The Relationship Between Biofouling Adhesion And Frequency Of Mechanical Cleaning To Control The Recruitment To Clear Coatings, Dylan Thomas Eggers Dec 2023

The Relationship Between Biofouling Adhesion And Frequency Of Mechanical Cleaning To Control The Recruitment To Clear Coatings, Dylan Thomas Eggers

Theses and Dissertations

There is a need to control biofouling on sensors and transparent windows in the marine environment. Clear silicone coatings offer a method to reduce the adhesion strength of marine organisms to the surface, however, these also require mechanical cleaning to maintain the surfaces free of fouling. This research evaluated the performance of eighty seven formulations and took the top two candidates to investigate a) the frequencies of wiping required by a brush to maintain two coatings and uncoated glass surfaces free of fouling and b) the effects of clear silicone coatings fouling release properties on required frequencies. The panels were …


Underwater Image Enhancement: A Pipeline For Underwater Computer Visions, Humberto Lebron Rivera Dec 2023

Underwater Image Enhancement: A Pipeline For Underwater Computer Visions, Humberto Lebron Rivera

Theses and Dissertations

Ocean exploration has surged in popularity and significance in recent years, including diverse areas like maritime archeology, underwater resources, and submerged structure inspection. The activities mentioned above heavily depend on vision and imagery, a challenge in the unpredictable marine world. This thesis presents a conditional generative adversarial network model for image-to-image translation problems. We designed and trained the model with the end goal of enhancing underwater images. Five metrics were employed for validation to quantify our model’s resulting enhanced images. By doing so, we aim to establish a pipeline that can leverage aerial computer vision algorithms for marine applications.

Our …


Investigating The Effects Of Collagen Alignment And Tricalcium Phosphate Incorporation On Osteoblast Cell Response, Kathryn Elizabeth Bock Dec 2023

Investigating The Effects Of Collagen Alignment And Tricalcium Phosphate Incorporation On Osteoblast Cell Response, Kathryn Elizabeth Bock

Theses and Dissertations

Every year, over 20 million people globally are affected by bone tissue loss due to disease or trauma. Bone tissue engineering (BTE) is touted as a promising approach to promote bone tissue repair and regeneration. In this realm, development of collagen-based scaffolds incorporated with a bioceramic is often attempted to generate tissue scaffolds that resemble the organic and inorganic composition of native bone. In addition, a variety of different collagen processing techniques have been employed to produce anisotropically aligned scaffolds that can provide the essential biochemical and structural cues to guide cell response. While there have been numerous studies on …


How Students Learn: Examining The Differences In Learning Strategies Between Flight And Nonflight Students, Jennifer A. Torres Dec 2023

How Students Learn: Examining The Differences In Learning Strategies Between Flight And Nonflight Students, Jennifer A. Torres

Theses and Dissertations

The purpose of this study was to determine if there were any differences in learning strategies between undergraduate flight and nonflight students attending a 4-year university that offered a Part 141 flight training program. Learning strategies were measured using Panadero et al.’s (2021) 30-item Deep Learning Strategies Questionnaire and its four subscales—Basic Learning Self-Regulation Strategies, Visual Elaboration and Summarizing Strategies, Deep Information Processing Strategies, and Social Learning Self-Regulation Strategies—all of which were the dependent variables. The primary independent variable was group membership, but the study also incorporated two covariates—self-efficacy and intrinsic value—which were measured using the respective subscales of Pintrich …