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At-Home Stroke Neurorehabilitation: Early Findings with the NeuroExo BCI System
No full textBackground: Democratized access to safe and effective robotic neurorehabilitation for stroke survivors requires innovative, affordable solutions that can be used not only in clinics but also at home. This requires the high usability of the devices involved to minimize costs associated with support from physical therapists or technicians. Methods: This paper describes the early findings of the NeuroExo brain&ndash;machine interface (BMI) with an upper-limb robotic exoskeleton for stroke neurorehabilitation. This early feasibility study consisted of a six-week protocol, with an initial training and BMI calibration phase at the clinic followed by 60 sessions of neuromotor therapy at the homes of the participants. Pre- and post-assessments were used to assess users&rsquo; compliance and system performance. Results: Participants achieved a compliance rate between <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>21</mn><mo>%</mo></mrow></semantics></math></inline-formula> and <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>100</mn><mo>%</mo></mrow></semantics></math></inline-formula>, with an average of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>69</mn><mo>%</mo></mrow></semantics></math></inline-formula>, while maintaining adequate signal quality and a positive perceived BMI performance during home usage with an average Likert scale score of four out of five. Moreover, adequate signal quality was maintained for four out of five participants throughout the protocol. These findings provide valuable insights into essential components for comprehensive rehabilitation therapy for stroke survivors. Furthermore, linear mixed-effects statistical models showed a significant reduction in trial duration (<i>p</i>-value &lt; 0.02) and concomitant changes in brain patterns (<i>p</i>-value &lt; 0.02). Conclusions: the analysis of these findings suggests that a low-cost, safe, simple-to-use BMI system for at-home stroke rehabilitation is feasible
Virtual Reality as a Stress Measurement Platform: Real-Time Behavioral Analysis with Minimal Hardware
No full textWith the growing use of digital technologies and interactive games, there is rising interest in how people respond to challenges, stress, and decision-making in virtual environments. Studying human behavior in such settings helps to improve design, training, and user experience. Instead of relying on complex devices, Virtual Reality (VR) creates new ways to observe and understand these responses in a simple and engaging format. This study introduces a lightweight method for monitoring stress levels that uses VR as the primary sensing platform. Detection relies on behavioral signals from VR. A minimal sensor such as Galvanic Skin Response (GSR), which measures skin conductance as a sign of physiological body response, supports the Sensor-Assisted Unity Architecture. The proposed Sensor-Assisted Unity Architecture focuses on analyzing the user&rsquo;s behavior inside the virtual environment along with physical sensory measurements. Most existing systems rely on physiological wearables, which add both cost and complexity. The Sensor-Assisted Unity Architecture shifts the focus to behavioral analysis in VR supplemented by minimal physiological input. Behavioral cues captured within the VR environment are analyzed in real time by an embedded processor, which then triggers simple physical feedback. Results show that combining VR behavioral data with a minimal sensor can improve detection in cases where behavioral or physiological signals alone may be insufficient. While this study does not quantitatively compare the Sensor-Assisted Unity Architecture to multi-sensor setups, it highlights VR as the main platform, with sensor input offering targeted enhancements without significantly increasing system complexity
Staged Effective Medium Modeling And Experimentalvalidation of Rock Thermal Conductivity
No full textThis thesis investigates the thermal conductivity of porous rocks under varying pressure and fluid saturation, integrating laboratory experiments with an effective medium modeling framework. It examines how thermal conductivity and wave velocity evolve with confining pressure and saturation state. Laboratory measurements show that both properties increase systematically with higher pressure and with water saturation. A staged differential effective medium (SDEM) approach successfully captures the nonlinear evolution of thermal conductivity and velocity with pressure and saturation, matching the experimental trends, which provides superior predictive accuracy and physical realism by accounting for pressure-dependent microstructural changes. The results demonstrate a unified link between thermal and elastic properties in granular rocks and offer a versatile modeling framework for multi-physics rock characterization. Practically, this research enables more reliable subsurface thermal modeling – for example, improving geothermal reservoir simulations – and informs geophysical evaluations by linking changes in seismic velocity to changes in heat transport properties
Prebiotics Improve Blood Pressure Control by Modulating Gut Microbiome Composition and Function: A Systematic Review and Meta-Analysis
No full text<b>Background:</b> Ingestion of dietary fibers (DFs) is a safe and accessible intervention associated with reductions in blood pressure (BP) and cardiovascular mortality. However, the mechanisms underlying the antihypertensive effects of DFs remain poorly defined. This systematic review and meta-analysis evaluates how DFs influence BP regulation by modulating gut microbial composition and enhancing short-chain fatty acid (SCFA) production. <b>Methods:</b> MEDLINE and EMBASE were systematically searched for interventional studies published between January 2014 and December 2024. Eligible studies assessed the effects of DFs or other prebiotics on systolic BP (SBP) and diastolic BP (DBP) in addition to changes in gut microbial or SCFA composition. <b>Results:</b> Of the 3010 records screened, nineteen studies met the inclusion criteria (seven human, twelve animal). A random-effects meta-analysis was conducted on six human trials reporting post-intervention BP values. Prebiotics were the primary intervention. In hypertensive cohorts, prebiotics significantly reduced SBP (&minus;8.5 mmHg; 95% CI: &minus;13.9, &minus;3.1) and DBP (&minus;5.2 mmHg; 95% CI: &minus;8.5, &minus;2.0). A pooled analysis of hypertensive and non-hypertensive patients showed non-significant reductions in SBP (&minus;4.5 mmHg; 95% CI: &minus;9.3, 0.3) and DBP (&minus;2.5 mmHg; 95% CI: &minus;5.4, 0.4). Animal studies consistently showed BP-lowering effects across diverse etiologies. Prebiotic interventions restored bacterial genera known to metabolize DFs to SCFAs (e.g., <i>Bifidobacteria</i>, <i>Akkermansia</i>, and <i>Coprococcus</i>) and increased SCFA levels. Mechanistically, SCFAs act along gut&ndash;organ axes to modulate immune, vascular, and neurohormonal pathways involved in BP regulation. <b>Conclusions:</b> Prebiotic supplementation is a promising strategy to reestablish BP homeostasis in hypertensive patients. Benefits are likely mediated through modulation of the gut microbiota and enhanced SCFA production
Investigating the Role of Copper During Neural Development
No full textCopper is essential to the health of mammalian biological systems, participating in vital metabolic and developmental processes. However, copper imbalances have proved to lead to higher rates of embryonic lethality and developmental defects. To maintain homeostasis, several proteins contribute to regulating copper levels, including CTR1, SOD1, and ATOX1. Nerve systems have shown profound changes when these proteins are functionally impaired, though it is unclear how copper levels specifically affect this process. To better understand the correlation between copper abundance and neurogenesis, we introduced stem cells to various copper environments and observed its effects on relevant protein expression, as well as differentiation and proliferation rates of the cell. Our findings show that copper deficient environments hinder cell proliferation, and excess copper has little effect. However, gene expression levels for our copper handling proteins of interest were affected in varying amounts based on the specific protein and the stage of development of the cell. These findings shed light on how copper imbalances ultimately affect neural cell development and differentiation.Chemistry, Department ofHonors Colleg
From AmplifyHER to AmplifyALL: Boys in an All-Girls Program and its Effects
No full textDuring the Fall 2024 semester, AmplifyHER, an all-girl CARE project, decided to add boys for the first time into the project. The project aims to increase self-confidence and self-advocacy in middle school students through one-on-one mentoring in public speaking. Through the addition of boys, we aim to compare results of pre and post-confidence surveys regarding public speaking to notice any gender differences that occur through mentor interviews. This program was implemented due to the gender biases that students experience in classrooms. For example, male students experience more attention from educators compared to female students. These gender biases in education have the power to shape girls' self-esteem, academic performance, and even career choices. The conditioning of girls to be passive in the classroom is what AmplifyHER attempts to combat. Finally, the program aimed to include boys to continue to minimize gender biases by mindfully interacting with mentees in a way that encouraged self-confidence in boys as well.Honors Colleg
A Comparison of Control Methods for Spacecraft Maneuvering With Run Time Assurance
No full textIn the vast subject of aerospace systems, safety is a critical factor in mission completion within the controls field. Controllers designed using data-based approaches like artificial intelligence must uphold the same levels of safety expected from modern controllers, such as Linear Quadratic Regulators. This is accomplished with the application of Run Time Assurance, which ensures the system states will remain within a predefined safe set of values, no matter the potentially dangerous control actions from the primary controller. This research compares control approaches for a deputy spacecraft conducting proximity operations to safely egress from near a chief spacecraft to a predefined relative parking orbit. This trajectory is described in a linearized relative motion reference frame and is calculated from a variety of modern control methods: Linear Quadratic Regulation, Linear Quadratic Integration, and Linear Quadratic Tracking. The initial conditions are chosen to force an unsafe trajectory to demonstrate how the use of Run Time Assurance ensures the system remains within the set of safe states. The two Run Time Assurance methods utilized are an active set invariance filter and a switching backup controller, both of which use a control barrier function to determine the safe set of values for the affected outputs with differing approaches of implementation. Three different scenarios are investigated to prove the safety bounds are not violated, each with a new situation addressed complete with new specific initial conditions. The results demonstrate that each modern controller is fully capable of implementing Run Time Assurance methods, while displaying varying levels of success based on the calculation-based values of the summation of control output and the rendezvous time
Evaluating Self-Efficacy, Expectation of Future Success, and Skill Perception in the Writing to Inspire Successful Education (WISE) Mentorship Program
No full textThe Writing to Inspire Successful Education (WISE) program, affiliated with the University of Houston Honors College, is a student-led initiative providing tutoring to fourth-grade students at the Raul Yzaguirre Schools for Success (P-STEM) in Houston. With a focus on supporting predominantly Spanish-speaking students with varying English proficiency levels, WISE aims to foster academic growth through personalized reading and writing mentorship while also developing leadership skills in undergraduate mentors. This study evaluates the program's impact on both mentors and mentees through surveys assessing three psychological constructs: self-efficacy, expectancy of future success, and perceived skill value. Self-efficacy, or the belief in one's ability to succeed, is a crucial factor influencing motivation and resilience. Expectancy-value theory suggests that students are more engaged when they anticipate meaningful outcomes from their efforts. By measuring these constructs, the study ensures that WISE effectively supports both mentees' literacy development and mentors' professional growth. Survey results indicate consistently high self-efficacy and positive skill perception among participants, reinforcing the program's effectiveness. While variations in survey timing due to organizational changes may have impacted longitudinal trends, results suggest that WISE successfully cultivates confidence and academic motivation. Future research should incorporate quantitative academic performance measures to further explore the relationship between self-efficacy and skill development. WISE continues to empower underserved students and mentors, fostering a commitment to education and long-term success.Psychological, Health, and Learning Sciences, Department ofHonors Colleg
The Role of Team Identification in Fans’ Adoption of Officiating Technology: A Study on the Impact of Video Assistant Referee
No full textOfficiating technology serves as a technological tool to assist officials (e.g., referee, umpire, judge) in improving the accuracy and fairness of sport officiating decisions. However, controversies surrounding its adoption of officiating technology remain uncertain, particularly regarding its impact on fan experience with potential drawbacks such as time delays and interruption of game flow. To understand sport fans’ perspectives, this study employed a concept of team identification developed by Social Identity Theory (SIT), which indicates the psychological connection and emotional attachment with a particular sport team. The main purpose of this study was to investigate the impact of the moderating role of team identification on performance expectations of officiating technology (PEOT), flow experience, and technology adoption regarding the Video Assistant Referee (VAR) system in soccer. Using SPSS AMOS 29, Structural Equation Modeling (SEM) and Confirmatory Factor Analysis (CFA) were employed to analyze the relationships among PEOT, flow experience, and technology adoption and to explore the moderation effects of team identification impacting other variables. Data (N = 607) was collected by Qualtrics and Prolific. The results of the model fit of both CFA and SEM were acceptable. The findings of this study indicated significant positive relationships between performance expectancy of officiating technology, flow experience, and technology adoption. More importantly, team identification negatively moderated the relationship between performance expectancy and flow experience, indicating that higher team identification weakens this positive relationship. However, team identification positively moderated the relationship between flow experience and technology adoption. The findings emphasize the critical role of performance expectancy and flow experience in technology adoption and highlight the moderating effect of team identification. Overall, the current study provides valuable insights into how soccer fans perceive the VAR system, emphasizing the need to balance technological advancements with fans' expectations and experiences to enhance their overall engagement and satisfaction
Synthetic Exploration of a New Yttrium Borate-Based Solid Solution, (K7-XNax)SrY2B15O30, for Deep UV Nonlinear Optical Applications
No full textThe general principles of second harmonic generation and structural properties of related compounds previously reported in the literature are examined and discussed. The synthesis of a solid solution of Yttrium Borates is reported and confirmed by powder X-ray diffraction (PXRD). The linear and nonlinear optical properties of these compounds are analyzed and a calculated crystal structure representative of these compounds is presented. Methods for further investigation of this family's properties are proposed for future studies.Chemistry, Department ofHonors CollegePhysics, Department o