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Understanding Structure-property relationship of Novel Solid Materials for Rational Design of Direct Air Capture Processes
No full textDirect air capture (DAC) of CO2, as one of the promising negative emission technologies, has been received extensive attentions from both academic and industrial communities in the recent years, aiming on mitigating increasing trend of atmospheric CO2 concentration and global temperature. Adsorption-based DAC using solid adsorbents is more attractive from its great potential in dropping the currently high cost of DAC process. The optimization of existing classes of solid sorbent materials and development of new solid sorbents are pivotal for moving adsorption-based DAC to next stage of affordable large-scale deployments. In this dissertation, we focus on understanding structure-property relationships of various solid materials for guiding design of next-generation materials for affordable DAC, and integrated DAC and in-situ CO2 conversion processes. In the first study, we performed a mechanistic study on amine-impregnated silica, highlighting the significance of aminopolymer morphology in DAC performances, which can be controlled by co-impregnation of hydroxyl-containing additives or surface modification of silica. We then move our focus from existing sorbent system to discovery of new class DAC sorbents based on porous transition metal hydroxides (PTMHs). In the second study, we successfully designed cost-effective sorbents with very competitive key DAC metrics including adsorption capacity, water-tolerance, oxidative stability and adsorption kinetics. The optimization strategies of pore engineering and metal doping are very effective to enhance its CO2 binding characteristics, supporting PTMHs act as a new prospective DAC platform. In the third project, a new class of single-component dual function materials (DFMs) based on porous nickel oxides was developed for integrated DAC and methanation (DACM) process. The new DFMs utilize metal-oxygen sites for CO2 binding and partially reduced metal center for hydrogenation. DACM performances of PTMOs (CH4 productivity and cycle stability) are remarkably enhanced from Ce incorporation, which rationally regulates electronic structures of pristine nickel oxides. The last project reported the first example of moisture swing adsorption (MSA) for DAC over metal-oxygen interfaces with comparable performances with traditional MSA sorbents. This example can expand the library of moisture swing adsorbents for advanced non-thermal driven DAC process design. Overall, the results presented in this dissertation serve to significantly enhance the fundamental understanding of novel solid materials that are of relevance to DAC and related applications, remarkably contributing toward affordable DAC
Do Discrimination and Adversity Drive the Inflammatory Basis of Suicidal Ideation in Black and Latinx Young Adults?
No full textIn recent years, the prevalence of suicidal ideation (SI) among young Black and Latinx individuals has been on the rise with racial/ethnic discrimination and adverse childhood events (ACEs) thought to partially explain this health disparity. Systemic inflammation—a product of over-activation of the body’s stress response system—has been hypothesized to play a unique predictive role in SI development. Experiencing racial/ethnic discrimination and ACEs can lead to systemic inflammation—possibly accounting for SI’s growing prevalence among young racial/ethnic minorities who experience ACEs and discrimination at disproportionate rates. Conversely, secure attachment relationships have been associated with a reduction in systemic inflammation and a lower risk for SI. The current study sought to test biological and relational mechanisms explaining SI among racial/ethnic marginalized young adults, specifically examining ACEs and racial/ethnic discrimination as risk factors, the mediating role of systemic inflammation, and the protective effects of close relationships. Undergraduate students at the University of Houston (UH) ages 18+ who identified as either Black, Latinx, or both were recruited to participate. Results only partially supported hypotheses, as greater attachment relationship anxiety and avoidance among Black participants was largely associated with greater SI severity and, in some cases, moderated the relation between attachment and IL-6. However, observed moderation effects were inverse to hypotheses, such that SI severity decreased with greater IL-6 concentration, suggesting IL-6 may not be unique to the investigated pathway model as predicted. No evidence was observed in support of proposed hypotheses among Latinx participants, and no evidence was observed supporting mediation effects of IL-6 in either subgroup. Potential methodological and contextual factors that may have contributed to the absence of significant findings are discussed herein, along with considerations for future research and clinical implications
Plasma microRNAs to Select Optimal Patients for Antibody Production from Anti-Addiction Vaccines
No full text<b>Background</b>: Cocaine and illicit amphetamines (disguised as &ldquo;Adderall&rdquo;) are being laced with fentanyl and producing accidental and intentional fatal overdoses. Vaccines can prevent these overdoses, but 33% of humans generate insufficient anti-drug antibody (AB) levels. Plasma microRNAs (miRs) can be used to predict non-responders. We have plasma stored from 152 cocaine vaccine trial participants following three vaccinations over 9 weeks and examined miRs as potential response biomarkers. <b>Methods</b>: We compared 2517 miRs before anti-cocaine vaccination in participants with the highest (n = 25) to the lowest (n = 23) antibody levels. False Discovery Rates (FDRs) were applied to identify differentially expressed (DE) miRs. We used miR target prediction pipelines to identify the miR-regulated genes. <b>Results</b>: Using a DE-FDR &lt; 0.05 and a &gt;3-fold difference between high- and low-AB responders yielded 12 miRs down and 3 miRs up compared to low-AB patients. Furthermore, 11 among 1673 genes were targeted by 3 or more of the 12 down DE-miRs. <b>Conclusions</b>: A significant DE-miR for identifying optimal antibody responders replicated previous vaccine study predictors (miR-150), and several more miRs appear to be strong candidates for future consideration in replications based upon significance of individual DE-miRs and upon multiple miRs converging on individual genes
Gender, Network Composition and Career Outcomes: An Analysis of Collaborative Ties
No full textCould a key to career success be who you know? Utilizing open-sourced data and computer science based data scraping methodologies, this study examined whether gender differences in network compositions exist, and if two network composition qualities of interest, the strength of ties and the proportion of ties to men, impact career success outcomes. Path analysis with bootstrapping was conducted using the lavaan package in R (Rosseel, 2012) for a sample of 480 academics and the co-author network they built within the first six years of their career. Although results do not support gender differences in network characteristics, nor an impact on compensation, average tie strength was positively related to productivity. As well, contrary to predictions, the proportion of ties to men was negatively related to a researcher’s current cumulative productivity. These findings add to current network theory and may help to better understand how co-authoring habits impact career success for those in academia
Negative Weight Attitudes and Disordered Eating Behaviors in Hispanic Adolescents: A Descriptive Study of Gender and Weight Status Associations
No full text<b>Background/Objectives</b>: Hispanic adolescents experience elevated rates of disordered eating behaviors and body dissatisfaction, yet limited research has examined how gender and weight status interact to shape these risks within this population. <b>Methods</b>: A cross-sectional survey was conducted among 680 Hispanic adolescents (ages 9&ndash;15) from a predominantly Mexican-American middle school. Participants completed the Modified Kids Eating Disorder Survey (M-KEDS), and height and weight were objectively measured to determine BMI-for-age percentile. Chi-square tests, Mann&ndash;Whitney U tests, and logistic regression were used to assess differences by gender and weight status, including interaction effects. Bonferroni correction was applied for multiple comparisons. Effect sizes (Cram&eacute;r&rsquo;s V, odds ratios with 95% CI) were reported. <b>Results</b>: Approximately 73% of participants reported body dissatisfaction, with significant differences observed by gender and weight status. Adolescents with overweight/obesity reported significantly higher negative weight attitudes and extreme weight control behaviors than healthy-weight peers (<i>p</i> &lt; 0.001), with large effect sizes. Females endorsed more disordered attitudes and behaviors, except for exercise to lose weight, which was more common among overweight/obese males. <b>Conclusions</b>: These findings underscore the high prevalence and significance of disordered eating behaviors in Hispanic adolescents, including those at a healthy weight. Results highlight the importance of culturally tailored, gender-sensitive screening and prevention strategies. Schools serve as critical settings for early identification, and tools like the M-KEDS can help address disparities in care access and improve outcomes among Hispanic youth
Mitochondrial Reactive Oxygen Species: A Unifying Mechanism in Long COVID and Spike Protein-Associated Injury: A Narrative Review
No full textPost-acute sequelae of SARS-CoV-2 infection (long COVID) present with persistent fatigue, cognitive impairment, and autonomic and multisystem dysfunctions that often go unnoticed by standard diagnostic tests. Increasing evidence suggests that mitochondrial dysfunction and oxidative stress are central drivers of these post-viral sequelae. Viral infections, particularly SARS-CoV-2, disrupt mitochondrial bioenergetics by altering membrane integrity, increasing mitochondrial reactive oxygen species (mtROS), and impairing mitophagy, leading to sustained immune activation and metabolic imbalance. This review synthesizes an understanding of how mitochondrial redox signaling and impaired clearance of damaged mitochondria contribute to chronic inflammation and multisystem organ symptoms in both long COVID and post-vaccine injury. We discuss translational biomarkers and non-invasive techniques, exploring therapeutic strategies that include pharmacological, non-pharmacological, and nutritional approaches, as well as imaging modalities aimed at assessing and restoring mitochondrial health. Recognizing long COVID as a mitochondrial disorder that stems from redox imbalance will open new options for personalized treatment and management guided by biomarkers. Future clinical trials are essential to validate these approaches and translate mitochondrial resuscitation into effective care for patients suffering from long COVID and related post-viral syndromes
Narrative Insights into the Transition from Clinical Fellow to Practicing Physicians
No full textBackground: The transition from fellowship to independent practice is a critical phase in a physician's career, involving new roles, administrative tasks, and expanded patient care. For those in academic medicine, balancing research, teaching, and clinical duties adds complexity, often leading to stress and burnout. Challenges such as physician shortages and an aging population compound these issues, yet this transitional period remains underexplored. Purpose: This study investigated the experiences of pathologists transitioning from fellowship to early-career practice, aiming to identify themes related to challenges, coping strategies, and support systems, with the intent to inform institutional practices for smoother adjustments. Methods: A qualitative narrative inquiry was conducted at a large academic institution in the Texas Medical Center. Six pathologists in their first two years of practice were selected via purposeful sampling. Data were gathered through in-depth, semi-structured interviews and analyzed using Charmaz's constructivist grounded theory, involving initial, focused, and selective coding alongside reflexive memo writing. Results: The analysis identified three primary categories of themes: Personal Challenges, Institutional Factors, and Professional Development. Within Personal Challenges, Work-Life Balance and Emotional Stress were frequently discussed, highlighting the importance of resilience in adapting to independent practice. Under Institutional Factors, the Importance of Support Systems emerged as a prominent theme, emphasizing the critical role of organizational support. Professional Development themes, including Cultural Integration and Communication Barriers, were less frequently mentioned, likely reflecting that most participants completed primary training within the United States. However, these challenges remain crucial, as foreign medical graduates often face additional cultural and communication adjustments. Addressing these gaps in onboarding support could foster a more inclusive and supportive environment. Conclusion: This study highlights the need for structured support systems, including mentorship programs and communication training, to ease the transition for new physicians. It advocates for healthcare organizations to develop frameworks addressing cultural competency, professional support, and guidance, especially amid a physician shortage. Implementing these recommendations may improve new physicians' well-being, retention, and healthcare outcomes. Future research should explore the long-term effects of these supports on physician transitions across specialties
Spectral Analysis of Aposematic Coloration Across Mimetic Populations of the Peruvian Ranitomeya
No full textAnimal coloration is under selection by a variety of factors such as mate choice, predation, and environmental stressors. Understanding the mechanisms by which different species produce colors and patterns, especially the same phenotypes, can detail how labile mechanisms of color production are. The species Ranitomeya imitator is a unique study system, as they have evolved various aposematic morphologies within Northern Peru that mimic species such as Ranitomeya variabilis and Ranitomeya fantascica (Symula et al. 2001). These species utilize Mullerian mimicry, which is characterized by a noxious species undergoing adaptive radiation to mimic previously established poison frogs in their environment. By quantifying the variations in coloration along and these transects, we can begin to identify evolutionary drivers of divergence and further our understanding of genetic mechanisms encoding color phenotypes (Stuckert et al. 2021).Biology and Biochemistry, Department ofHonors Colleg
Life in Transit: Realistic View on Starship-Housed Habitat for Mars Exploration
No full textThe sustainable habitation of spacecraft during extended interplanetary missions represents a critical frontier in space architecture that demands robust solutions. This research examines the architectural and systems integration challenges inherent in adapting SpaceX's Starship vehicle to accommodate an eight-person crew during a nine-month Mars transit. Through computational modeling and comparative analysis of existing space habitation systems, this study addresses the volumetric constraints that impact storage optimization and resource allocation. Particular attention is given to the integration of hydrogen fuel cells as primary power generators, with emphasis on their thermodynamic efficiency and operational longevity in closed-loop environments. The research methodology incorporates both quantitative assessment of critical life support parameters and qualitative evaluation of human factors considerations, resulting in a comprehensive habitat framework. Findings indicate that successful long-duration habitation requires not merely isolated technological solutions but rather an integrated approach where power generation systems and resource management operate symbiotically. This work contributes to the emerging field of deep space habitat design by establishing evidence-based parameters for life support system redundancy and storage accessibility that balance engineering constraints with human physiological and psychological requirements. These insights may inform future spacecraft architecture decisions as humanity advances toward establishing a sustained presence beyond Earth orbit
Correlational Study Between "Attention" and "Delayed Recall" Sections of MoCA Test Across Age, Gender, and Education
No full textCognitive decline is a significant concern for everyone. However, cognitive health is not often explored, especially in the Vietnamese community. Houston is the 2nd largest Vietnamese-populated metropolitan area in the United States and over 10% of Houston's Vietnamese community consists of Vietnamese people 65 years and older. Yet, hardly anyone checks their cognitive health during their annual checkup. To address this gap, the Cougar Cognitive Health Initiative (CHAIN) program was established and started offering free cognitive assessments to older Vietnamese people in Houston. This study aimed to examine the relationship between age, gender, and educational attainment and the Delayed Recall and Attention scores on the Montreal Cognitive Assessment (MoCA). Using T-test and Chi-Squared test, the results suggested that age-related correlations to both Delayed Recall and Attention were weak, gender did not have much impact on scores from both respective areas, while education showed a more significant impact on Attention than Delayed Recall. Future studies could also enhance cognitive assessments by integrating MoCA with other tools, such as eye movement tracking, to improve the detection of cognitive impairment while controlling for factors like education and age.Social Work, Graduate College ofHonors Colleg