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Development Of A Wearable Biosensor For Cortisol Detection In Human Sweat Utilizing Pani/Peo Polymer Blend And Nitrogen-Doped Graphene Quantum Dots, Cesar Sanchez

Theses and Dissertations

Since the development of the first biosensor in 1962, the evolution of commercially available wearable biosensors has been driven by an increasing consumer interest in real-time health tracking. However, challenges related to sensor sensitivity and cost have hindered progress. Deploying a novel approach, the biosensor integrates a blend of Polyaniline (PANi) and Polyethylene Oxide (PEO) along with Nitrogen-doped Graphene Quantum Dots (N-GQDs) to enhance sensitivity and electroactivity, crucial for cortisol detection. To optimize performance, three distinct synthesis methods for N-GQDs; hydrothermal, microwave, and hot plate synthesis were compared employing a bottom-up approach utilizing citric acid (CA) as the primary reactant …

Primary And Parametric Resonances Of Angled Mems And Nems Cantilever Resonators, Benjamin Matthew Huerta

Theses and Dissertations

This work investigates the resonances of electrostatically actuated micro- and nano-electromechanical systems (MEMS/NEMS) uniform cantilever resonators positioned at an angle relative to a ground plate. The resonances considered in this work include primary and parametric resonance. For each resonance, the amplitude-frequency and amplitude-voltage responses are presented. The model is constructed using Euler-Bernoulli beam theory. Results are obtained by construction of a Reduced Order Model considering up to the first five modes of vibration. The Method of Multiple Scales is used when considering only the first mode shape, and the software AUTO 07p is used for higher terms. Two models are …

Low-Dimensional Learning For Remaining Useful Life Prediction Of Batteries Operating Under Various Environments, Rodrigo Benavides

Theses and Dissertations

In reliability, we typically define the standard operating conditions under which a component operates. However, the differences in battery operating conditions cause variability in the degradation patterns of identically manufactured batteries, rendering remaining useful life prediction a major challenge. To aid this task, several sensors are utilized to monitor battery state-of-health. However, traditional prognostics algorithms do not scale well to the volume of data generated. Furthermore, several authors do not explicitly consider operating environments in their prediction models. Therefore, we present a high-dimensional data analytics framework that integrates operating environment information for battery prognostics. This framework combines Multilinear Principal Component …

A Diminished Alliance: The Effects Of French American Relations On The Leadership Of Washington, Adams, And Jefferson 1789-1809, Eric Christopher Carlson

Theses and Dissertations

This research examines the relationship between the United States and France during the first three presidencies and how it influenced the leadership and decision-making of Washington, Adams, and Jefferson. Throughout the thesis, it is argued that the most critical developments in the United States during these presidencies were connected to diplomatic relations with the French along with each leaders own private, but often public, perceptions of the French. The two decades that these three leaders were in office witnessed significant transformation in U.S.-French relations, especially as the French Revolution spiraled into a full-scale European conflict that threatened American neutrality. In …

Multi-Theoretic Perspective Of Backer Decision-Making In Crowdfunding: Interplay Of Backer, Founder And Ai, Maliha Alam

Theses and Dissertations

Crowdfunding has become a transformative mechanism for financing innovation, connecting creators directly with backers while bypassing traditional funding barriers. Despite its rapid global growth, only about 33.7% of campaigns succeed, largely due to ineffective communication of value propositions and lack of backer engagement. This dissertation investigates the complex interplay between project founders, backers, and emerging AI technologies to understand the factors influencing donation intention and to enhance crowdfunding success prediction.

Adopting the behavioral decision-making framework, I draw on multiple theoretical perspectives- signaling theory, the dual-process model of persuasion, and the cognitive-affective trust framework to examine founder- backer interactions. Using a …

The Impact Of Positive Psychology Use Upon Gls Outcomes For People With Chronic Pain Syndromes, Timothy Michael Curtis

Theses and Dissertations

The essence of being human is realized by our discovery of meaningful purpose throughout each important stage of our lives. If we perceive that we lack this meaningful purpose in our lives, it could become a distressful source of suffering to our sense of well-being emotionally, cognitively and perhaps, spiritually. A strong indicator of well-being comes from a good evaluation we ascertain as to how well we believe outcomes in our lives are consistent with our goals and values, which is also known as satisfaction with life. Research findings indicate that the more someone experiences repeated negative life events, the …

Arginine Vasotocin And Corticosterone In Nesting And Non-Nesting Loggerhead Sea Turtles In X’Cacel-X’Cacelito Sanctuary, Krista Blair Reed

Theses and Dissertations

Sea turtles exhibit distinct behaviors before and after egg laying, however, not all individuals successfully oviposit. Some females display disruptions in their typical nesting behavior, returning to the water without laying eggs, which is referred to as a non-nesting emergence (NNE). NNEs can be due to external disturbances on the beach, but why they occur is often unclear. Arginine vasotocin (AVT) is a neuropeptide involved in various physiological processes, including stimulating smooth muscle contraction of the oviduct to facilitate egg deposition in nesting sea turtles. On the other hand, corticosterone is the primary stress hormone in sea turtles and is …

Computational And Experimental Analysis Of Knee Kinematics And Gait Variability: The Effects Of Load, Speed, And Fatigue On Human Motion, Alfirio Trejo Jr.

Theses and Dissertations

This thesis investigates the biomechanical behavior of the human knee under varying conditions of motion, load, and fatigue, with a focus on clinical angle analysis and gait stability. Four studies were conducted using motion capture data and a modified Grood and Suntay Joint Coordinate System (JCS) to evaluate knee joint kinematics—specifically flexion-extension, abduction-adduction, and internal-external rotation. The first study examined the effects of incremental weight loads during isolated knee extension exercises, revealing dose-dependent increases in abduction and internal rotation that may contribute to joint stress. The second study assessed the impact of walking speed and asymmetric loading on gait, showing …

Comparative Analysis Of Sequential And Non-Sequential Modeling Techniques For Ddos Attack Detection With Explainable Ai, Vincent Agbenyeavu

Theses and Dissertations

Cybersecurity is known today as one of the greatest challenges of the modern era. Among the various types of cyber-attacks that threaten our security, the Distributed Denial of Service (DDoS) attack is among some of the most common, effective, and well-recognized attack strategies. Since this form of attack is meant to disrupt the availability factor covertly, it can be detrimental to the targeted machines and difficult to discover. Because of that, there have been several approaches, as well as solutions that have been devised to detect it as accurately and efficiently as possible. In this study, four sequential data modeling …

Exploring Transcriptional Stress Responses In Sorghum And Evolutionary Insights Into Yth Domain Proteins Across Plants, Shikha Bharti

Theses and Dissertations

Understanding how plants respond to abiotic stress is crucial for enhancing crop resilience in the face of climate change. This thesis explores plant stress adaptation mechanisms through two interlinked studies that address different aspects of gene regulation. The first study investigates the transcriptional dynamics of Sorghum bicolor under drought and heat stress at 1-hour and 6-hour time points. By employing 3'-end RNA sequencing, this study provides a comprehensive temporal view of gene expression changes, revealing stress-responsive transcription factors, hormone-associated pathways, and chromatin regulators. The comparative analysis highlights both common and distinct molecular responses between drought and heat stress, providing insights …

Biological, Histological, And Immunohistochemical Responses To Heat Stress In Common Goldfish, Carassius Auratus, Ngozichukwu Francis Ngozichukwu

Theses and Dissertations

Global climate change has led to rising temperatures, posing significant challenges to aquatic ecosystems and the health of ectothermic species such as goldfish (Carassius auratus) This thesis investigated the effects of heat stress on growth performance, histological alterations, and molecular stress responses in the gill and kidney tissues of goldfish Fish were exposed to control (24°C), medium (28°C), and high (32°C) temperatures for two weeks Growth parameters, including instantaneous growth rate (IGR), absolute growth rate (AGR), body value gain (BVG), and condition factor, were evaluated alongside histological and immunohistochemical markers of stress Results revealed that high temperature significantly reduced AGR …

Analyzing How Taste And Nutrition Impact Learning And Memory In Honey Bees Through Olfactory Associative Conditioning, Alessandra Elizabeth Perry

Theses and Dissertations

Honey bees detect sweet nectar, but not all sweet-tasting sugars provide nutrition. Unlike fruit flies, which can learn to avoid non-nutritious sweet foods, bees may lack this ability. To test if bees form caloric frustration memory (CFM), we conditioned them using odors paired with L-glucose (sweet but non-nutritious) or D-glucose (sweet and nutritious). Bees rewarded with L-glucose showed lower learning and long-term memory compared to D-glucose. Bees cannot differentiate between an odor associated with rewards containing malaise-causing compounds and an odor associated with a reward alone during differential conditioning. Therefore, we used differential conditioning to determine if lower acquisition in …

Transcriptomic Study On The Effect Of Salt Stress In Sorghum Bicolor Seedlings, Joshwa A. Gandy

Theses and Dissertations

The global impact and reliance on cereal crops, and sorghum in particular, is paramount for worldwide food security and for the livelihood of hundreds of millions of people. The detrimental effects of salt stress on crop plants and the huge economic losses it causes by affecting agricultural output worldwide is a devastating issue with huge impacts, which have prompted research to combat salinity in numerous ways. Understanding how cereals respond to the negative effects of salt stress is crucial for enhancing their salt tolerance. In this study of sorghum, we used a 3’-end RNA sequencing approach to elucidate major salt …

Interdigitated Gear-Shaped Screen-Printed Electrode Using G-Pani Ink For Sensitive Electrochemical Detection Of Stress Related Hormones Dopamine And Cortisol, Pritu Parna Sarkar

Theses and Dissertations

This research introduces a novel interdigitated gear-shaped graphene-based electrochemical biosensor for the simultaneous detection of dopamine (DA) and cortisol. Modified with graphene–polyaniline (G–PANI) conductive ink, the sensor increased active surface area—94.52% and 57% higher than Metrohm DropSens 110 and circular printed sensors, respectively. Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR) Spectroscopy and X-ray diffraction (XRD) were employed for physicochemical characterization. The sensor detects dopamine and cortisol over a linear range of 0.1–100 µM, with limits of detection of 0.043 µM (R² = 0.98) and 0.0577 µg/mL (R² = 0.976), respectively, in phosphate-buffered saline (PBS) using redox probe. Electrochemical performance …

Chronic Lower Extremity Anomalies: Impact Of Diabetic Induced Foot Amputations On Human Locomotion, Anthony Arnoldo Melgar

Theses and Dissertations

This research aims to understand the physiological changes that the human body undergoes post partial foot amputation (PFA). A total of three studies were conducted to fully comprehend biomechanical changes and adjustments that occur during locomotion for affected individuals. The first study of this thesis focuses on obtaining kinematic data for both the ankle joint angle and ankle joint torque for the healthy population, as well as for the affected PFA population. Results were compared, and notable differences were present between the two. The second study of this thesis dealt with individual muscle forces. To obtain the muscle force data, …

Opa1-Mediated Mitochondrial Dynamics In Myogenic Differentiation Of C2c12 Myoblasts, Daniel Eloy Bazan

Theses and Dissertations

Mitochondria play a pivotal role in metabolic energy production, cellular signaling, and apoptosis. To carry out these key cellular roles, mitochondria dynamically balance their organization through opposing including fusion and fission processes. The balance between mitochondrial fusion and fission is regulated by key proteins such as OPA1 (optic atrophy 1) and OMA1 (overlapping activity with metalloprotease). More recently, mitochondria have been increasingly revealed to play key roles in cellular differentiation, where metabolic demands are reprogrammed. This study aims to elucidate the specific roles of OPA1 and OMA1 in the differentiation of C2C12 myoblast cells into myotubes.

Our data demonstrates that …

Machine Learning Applications For Evaporation Predictions From Small Reservoirs: Potential Water Savings For Lower Rio Grande Valley, Texas, Syed Muhammad Fahad Abdullah

Theses and Dissertations

Local-scale reservoirs are important to regional water balance, but these are often overlooked. This study presents a robust machine learning (ML) approach leveraging reanalysis datasets to estimate daily evaporation for local-scale reservoirs in semi-arid South Texas. Selected models were trained with daily lake evaporation model (DLEM) estimates and used climatic and reservoir-specific properties as feature input variables. The multi-reservoirs training approach ensured applicable model generalization. Results show promising predictive performance with R² values ranging from 0.55–0.67 (testing) and 0.64–0.78 (validation), NSE values ranged from 0.54 0.67 (testing) and 0.64–0.78 (validation), and RMSE values ranged between 1.52–1.80 mm/day (testing) and 1.22–1.58 …

Low-Cost Monitoring And Fingerprinting Of High-Powered Electric Systems, Kwabena Buamono Aboagye-Otchere

Theses and Dissertations

Electric motors are vital to industry, transport, and energy, yet their maintenance challenges persist. While traditional reactive maintenance leads to costly downtime and safety risks, predictive maintenance, especially through IoT and machine learning offers early fault detection and operational efficiency. However, this shift introduces security concerns due to unintended magnetic emissions from motors. These emissions, though useful for non-intrusive monitoring, can be exploited to eavesdrop on sensitive industrial processes. This dissertation explores the dual nature of magnetic emissions: their value in motor diagnostics and their potential as a security vulnerability. It demonstrates how emissions can identify motors, monitor health, and …

Computational Calculations On Zno (0001) And Zno (1010) Surfaces With And Without Pd Adatoms, Amit Aich

Theses and Dissertations

In this research work, first-principles density functional theory (DFT) was used to study O-terminated, Zn-terminated ZnO (0001) surfaces and non-polar ZnO (1010) surfaces. Both clean surfaces and those with Pd or PdO adatoms were examined. Adsorption was considered at O, Zn and hollow sites. After structural relaxation, we analyzed the electronic, optical and adsorption properties. The O-terminated ZnO (0001) surface has a larger band gap of 0.76 eV and p-type conduction. The Zn-terminated surface has a smaller band gap of 0.15 eV and shows n-type behavior. Pd adsorption modifies ZnO’s electronic structure in a site-dependent manner. On O-terminated surfaces, it …

Comparison Of Recovery Methods After Resistance Exercise For Power Performance, Isaac D. Huerta

Theses and Dissertations

Elite athletes engage in intense training to secure marginal performance advantages, placing considerable physical strain on their bodies. Effective recovery techniques are critical to rapidly restore physical function. Conventional methods like ice baths, hydrotherapy, and massages are often impractical due to cost and logistical barriers. This study examined the efficacy of voluntary deep slow breathing (VDSB) as a cost-effective recovery method compared to static stretching (SS) and no recovery method (control) in untrained male athletes aged 18–26. Using a within-subjects, randomized crossover design over four weeks, participants visited the lab seven times to complete a standardized full-body workout involving plyometric …

Phenotypic Plasticity In Response To Abiotic Factors In Silverleaf Nightshade (Solanum Elaeagnifolium), And The Effectiveness Of North American Lacebug (Gargaphia Arizonica Drake And Calvo) As A Biocontrol, Marco Andre Silguero

Theses and Dissertations

Silverleaf nightshade (Solanum elaeagnifolium) is a widespread invasive weed in South Texas and other arid regions, where it reduces crop productivity, competes with native vegetation, and resists conventional control methods. Its ability to thrive across different environments is linked to phenotypic plasticity, allowing it to adjust growth and physiology in response to light and water availability. In this thesis, I examine the role of plasticity in S. elaeagnifolium under field conditions and evaluate the potential of the North American lacebug (Gargaphia arizonica) as a biological control agent. Field observations were used to measure plant traits such as height, stem thickness, …

The Abduction Of Juan Manuel Fangio And Its Impact On The Cuban Revolution, Shalom Nissi Ramirez

Theses and Dissertations

On February 23, 1958, Juan Manuel Fangio, the five-time Formula One Champion, was kidnapped by the 26th of July Movement (M-26) in Havana, Cuba, during the Cuban Revolution. The kidnapping took place on the eve of the Havana Grand Prix as an act of sabotage against Fulgencio Batista's government. Fangio's abduction became a symbol of political resistance, challenging Batista's authority and raising the profile of M-26 as a revolutionary group. This thesis examines how the incident, amplified by worldwide media coverage, influenced international perceptions of the Cuban Revolution. It argues that using Fangio’s fame strategically helped accelerate awareness of the …

The Effects Of A Tier 2 Intervention On The Behavior Of Elementary School Students Participating In Second Step: Enhancing A Schoolwide Social-Emotional Learning Curriculum, Charlotte Annalee Kennington

Theses and Dissertations

After reviewing the current research literature on the effects of social-emotional learning (SEL) on the behavior of elementary-age children, it was clear that there was limited research data on the effects of Tier 2 interventions designed to augment the effects of schoolwide SEL programs. Specifically, to what extent could a brief, group-delivered intervention improve the academic engagement, problem behavior, and socially appropriate comments of fifth-grade students receiving schoolwide SEL through Second Step in a traditional public school? Three fifth-grade students were recruited to participate in this study who all engaged in frequent problem behavior during Second Step lessons and throughout …

Molecular And Clinical Insights Into Role Of Gper In Hepatocellular Carcinoma (Hcc), Hossain Ahmed

Theses and Dissertations

Metabolic dysfunction–associated steatotic liver disease (MASLD), encompassing stages from steatosis (MASLD) to steatohepatitis (MASH), cirrhosis, and hepatocellular carcinoma (HCC), is the most prevalent chronic liver disease worldwide, yet molecular markers of progression remain limited. The G protein–coupled estrogen receptor (GPER), a non-genomic estrogen receptor with metabolic and anti-inflammatory roles, emerges as a candidate regulator in hepatic pathophysiology. In this Dissertation thesis, we have delineated for the first time clinicopathological assessment of liver biopsies across MASLD stages revealing a robust inverse correlation between GPER expression and disease severity. Higher GPER levels in early MASLD associated with favorable metabolic and biochemical profiles, …

Insights Gained From Applying Molecular Techniques To Gray Triggerfish (Balistes Capriscus Gmelin, 1789) In The Mexican Caribbean, The Southern And Northwestern Gulf Of Mexico, Geaceli G. Orive

Theses and Dissertations

This study focuses on Balistes capriscus (Gray Triggerfish), a reef-associated species dependent on hard-bottom habitats in the Gulf of Mexico (GOM). Using mitochondrial DNA barcoding and phylogenetic analyses, genetic structure across four sites was assessed: Rio Grande Valley (RGV), Veracruz, Chinchorro Bank, and Xahuayxol. Samples from RGV and Veracruz exhibited limited haplotype diversity, minimal nucleotide divergence, and weak genetic differentiation-patterns consistent with recent population expansion and ongoing connectivity within the GOM. While the study centered on B. capriscus, all individuals from Chinchorro and Xahuayxol unexpectedly grouped with Canthidermis maculata (Spotted Oceanic Triggerfish), suggesting misidentification, cryptic diversity, or taxonomic uncertainty in …

Advancing Real-World Implementation Of The Well Optimized Linear Finder (Wolf) High-Speed Atmospheric Turbulence Compensation Method, Timothy Evan Coon

Theses and Dissertations

This dissertation advances the real-world implementation of the Well Optimized Linear Finder (WOLF) method for high-speed Atmospheric Turbulence Compensation (ATC). Atmospheric turbulence introduces phase aberrations into optical wavefronts and degrades image quality in terrestrial imaging systems. Traditional phase diversity methods are computationally intensive and poorly suited to real-time operation. The WOLF method addresses these limitations through a novel, point-wise formulation of the optical transfer function (OTF) as a structured autocorrelation of the generalized pupil function (GPF). This formulation enables the estimation of phase aberrations at individual spatial coordinates with distributed computational complexity.

The research begins by developing a MATLAB-based simulation …

Commitment And Betrayal In Intimate Relationships: A Grounded Theory Analysis, Megan Van Alfen Brown

Theses and Dissertations

Commitment and betrayal are key aspects of a relationship that have impact on the quality or health of the relationship. The purpose of this paper was to use qualitative grounded theory methods to explore how commitment and betrayal are experienced in intimate relationships and to explore the outcomes of both. The data were taken from a larger project on healthy and unhealthy relationships where participants were recruited through convenience and theoretical sampling. Semi-structured interviews were conducted and constructivist grounded theory methods were used to code, generate, and refine prominent categories in the data. Findings revealed that commitment is experienced through …

Characterizing Host And Viral Factors Relevant To Turkey Hemorrhagic Enteritis Virus-Induced Immunosuppression, Abraham Quaye

Theses and Dissertations

Turkey hemorrhagic enteritis virus (THEV) is an adenovirus (AdV) that causes hemorrhagic enteritis (HE) in turkeys, a debilitating disease affecting predominantly 6-12-week-old turkey poults characterized by immunosuppression (IMS) and intestinal lesions leading to bloody diarrhea. Although a naturally-occurring avirulent THEV strain has been adopted as live vaccine and has proven effective at preventing HE in turkeys, it still retains its immunosuppressive ability. Thus, vaccinated birds are rendered more susceptible to opportunistic infections and death than unvaccinated cohorts, leading to substantial economic losses. This dissertation focuses on elucidating both host and viral factors mediating THEV-induced IMS in turkeys. As THEV gene …

Characterizing Gastric Cancer Tumor Immune Microenvironment Through Extracellular Vesicles, Claire Elizabeth Bruno

Theses and Dissertations

The tumor immune microenvironment (TIME) critically influences cancer progression and determining therapeutic response. As immunotherapies continue to improve and reshape cancer treatments, there is a need for tools that can more efficiently and accurately assess and monitor the TIME. Extracellular vesicles (EVs), especially small EVs (sEVs), are lipid-bound nanoparticles that carry proteins, DNA, and RNA reflective of their cell of origin, offering a novel, non-invasive biomarker of the TIME. This makes them a promising candidate for immune profiling and treatment monitoring in cancer. This thesis investigates the potential of EVs as biomarkers for TIME composition and immune activity. An analysis …

Modeling Steady-State Navier-Stokes Flow Using Structure-Preserving Truncated Hierarchical B-Splines, Daira Sofia Velasco Vega

Theses and Dissertations

Accurate simulation of incompressible steady-state fluid flow is critical for engineering applications where mass conservation, numerical stability, and geometric fidelity are essential. This thesis develops and analyzes a structure-preserving isogeometric framework for steady-state incompressible Navier"“Stokes simulations using truncated hierarchical B-splines (THB-splines). By leveraging divergence-conforming spline spaces designed to keep the fluid's divergence exactly zero based on the mathematical de Rham complex, this method ensures the fluid remains incompressible everywhere without needing extra stabilization techniques. The use of THB-splines allows the mesh to be refined locally in areas where the flow changes sharply. It still keeps the solution smooth and ensures …