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A Novel DRL-Transformer Framework for Maximizing the Sum Rate in Reconfigurable Intelligent Surface-Assisted THz Communication Systems
No full textTerahertz (THz) communication is a key technology for sixth-generation (6G) networks, offering ultra-high data rates, low latency, and massive connectivity. However, the THz band faces significant propagation challenges, including high path loss, molecular absorption, and susceptibility to blockage. Reconfigurable intelligent surfaces (RISs) have emerged as an effective solution to overcome these limitations by reconfiguring the wireless environment through passive beam steering. In this work, we propose a novel framework, namely the optimized deep reinforcement learning transformer (ODRL-Transformer), to maximize the sum rate in RIS-assisted THz systems. The framework integrates a Transformer encoder for extracting temporal and contextual features from sequential channel observations, a DRL agent for adaptive beamforming and phase shift control, and a hybrid biogeography-based optimization (HBBO) algorithm for tuning the hyperparameters of both modules. This design enables efficient long-term decisionmaking and improved convergence. Extensive simulations of dynamic THz channel models demonstrate that ODRL-Transformer outperforms other optimization baselines in terms of the sum rate, convergence speed, stability, and generalization. The proposed model achieved an error rate of 0.03, strong robustness, and fast convergence, highlighting its potential for intelligent resource allocation in next-generation RIS-assisted THz networks
Cigarette and Smokeless Tobacco Product Use Among South Asian Americans and Health: The Role of Gender and Acculturation
No full textBackground: The use of tobacco products among South Asians is relatively high. Moreover, there is a high prevalence of oral smokeless tobacco products (SLT), particularly products containing Dypsis Lutescens plant, a central nervous system stimulant designated as a carcinogen. The use of SLT products among South Asians Americans is embedded within practices that can be influenced by gender and acculturation. Few studies have focused on the co-use of cigarettes and SLT products among South Asian Americans. Purpose: This study examined the co-use of cigarettes and SLT products among South Asian American adults and investigated the associations between distinct user groupings on variables such as gender, acculturation, physical health, marital status, and nicotine dependence. Methods: Data from a sample of 276 South Asian Americans were analyzed using multinomial logistic regression (MLR) which compared four cigarette and SLT user status groups: (1) Non-Users; (2) Exclusive SLT Users; (3) Exclusive Cigarette Users; and (4) Dual Users. Results: The overall model was significant compared to the null model [χ2 (15) = 107.1, p < 0.001]. With the Non-Users as the reference category in the MLR model, acculturation, physical health, and marital status were significant predictors of cigarette & SLT user status group membership with unique distinctions based on use and co-use. There were also statistically significant differences in nicotine dependence scores between the Exclusive Cigarette Users and the Dual Users (F(1,144) = [5.28], p = 0.023). The Exclusive Cigarette Users demonstrated significantly higher mean nicotine dependence score (M = 2.2, SD = 0.84) relative to the mean score (M = 1.9, SD = 0.93) among the Dual Users. Conclusions: The use of exclusive SLT products, as well as the dual use of cigarettes and SLT products, was found to be higher in this study compared to previous studies of South Asian Americans and oral tobacco product use in the general US population. These findings support the need for greater assessment of the use of such products in both the context of clinical practice and future research with South Asian Americans
First-Generation Status and Negative Mental Health Outcomes as Moderated by Familial Basic Psychological Need Frustration
No full textAmong minority populations, Latinx women have a disproportionate risk of major depressive disorders (Lopez et al., 2018). Self-determination theory's basic psychological needs theory (Deci & Ryan, 2000) asserts that satisfaction is instrumental to optimal well-being (Vansteenkiste et al., 2020). BPN frustration satisfaction, therefore, may exacerbate (or buffer) 1st generation status among Latina American women. We propose that basic psychological need satisfaction within the family can buffer 1st-generation effects on depression, anxiety, and stress (DASS-21; Henry & Crawford) and negative mental health (MHI-5; Berwick et al., 1991). Hypotheses were tested using a secondary dataset with a sample of 318 Latina American women recruited from the Greater Houston community and UH undergraduate pools (62 first generation, 257 second generation and greater). Moderation tests indicated that there was no significant interaction between generation status and need satisfaction on any of the mental health outcomes. However, there was a significant interaction between generation status and need frustration on an assessment of mental health (MHI-5) such that 1st generation participants self-reported more negative mental health symptoms. There was no significant interaction between generation status and need frustration on depression, anxiety, and stress (DASS-21).Psychology, Department ofHonors Colleg
Inhibiting Mutant RAS Inhibitors in Cell-Based Assays
No full textRAS proteins, including KRAS and NRAS, are critical regulators of signal transduction frequently mutated in various cancers, resulting in enhanced downstream signaling. Developing targeted therapies against mutant RAS remains a significant challenge. This study investigates the effectiveness of novel compounds in inhibiting RAS signaling and reducing cell viability in mutant RAS cell lines. We hypothesize that these compounds will suppress phosphorylated ERK (p-ERK) levels and decrease cell viability in RAS-mutant cells. Wild-type and mutant RAS cell lines were cultured in RPMI-1640 medium supplemented with 10% FBS. Compounds were administered for two hours before evaluating p-ERK levels using the AlphaLISA pERK1/2 assay. Additionally, 2D and 3D viability assays were conducted over seven days using Promega's CellTiter-Glo reagent. Results revealed that RAS mutant cells were more sensitive to the tested compounds than wild-type cells, showing significant reductions in both p-ERK levels and viability. Notably, the compounds demonstrated a stronger inhibitory effect in 3D cultures, mimicking in vivo conditions more closely. These findings validate the hypothesis that targeting mutant RAS with specific inhibitors can effectively suppress oncogenic signaling and reduce cell viability. This study highlights the potential for developing new RAS-targeted therapies, with future work focusing on optimizing dosing strategies and evaluating compound effectiveness in vivo. Keywords: RAS inhibitors, KRAS, NRAS, p-ERK, AlphaLISA, CellTiter-Glo, 3D cell culture, cancer therapy. [This project was completed with contributions from Lisa Maria Mustachio and Mary Geck Do from UT MD Anderson Cancer Center.]Honors Colleg
Implications for Weight Loss and Weight Cycling What All Does Your Immune System Remember?
No full textIf you've heard about immune memory, you've likely heard it in the context of prior infection or vaccination. But your immune system can also develop memory to different lipids and sugars. This memory is likely evolutionary protective, as it improves your ability to fight off subsequent infections. However, it also increases the risk for diseases like atherosclerosis and diabetes. We specifically find this to be true following significant weight loss- when lipids are released from your fat tissue. While metabolic measures like blood pressure and blood glucose return to "normal" levels after weight loss, immune cells in the fat remain primed for inflammation. Upon weight regain, these memory cells increase inflammation and likely worsen the risk for diabetes. We are working now to understand if immune memory can be targeted therapeutically to improve health for those who have weight cycled over their lifetime
Personality, Materialism, and the Parent-Child Relationship: A Study of Alignment and Impact
No full textThe Ideal Standards Model (ISM; Fletcher et al., 2000, 2020) examines the alignment between an individual's perception of their close other's current characteristics and their idealized standards, with greater alignment linked to more favorable relationship outcomes. ISM has been extensively researched in romantic relationships, but less is known about how it applies to parent-child relationships. The purpose of this study was to examine the relationship between the quality of a person's relationship with their primary caregiver and their perceptions of matching parental traits, specifically traits that are either considered more materialistic or more personal. Participants (N = 177) completed an online survey evaluating the quality of their relationships and the traits of their parents. EFA distinguishes between matching standards of personal characteristics (α =.93) and materialistic characteristics (α =.87). Simultaneous multiple regression indicated that both types of traits positively predicted relationship quality with their caregiver, b=.598, t(173)=8.56, p<.001 and b=.251, t(173)=3.52, p<.001, respectively. These findings extend the ISM framework to parent-child relationships, suggesting that alignment with personal characteristics is a stronger predictor of relationship quality compared to materialistic traits. The study adds to a deeper understanding of parent-child dynamics and highlights the importance of both personal and materialistic ideals in shaping these relationships. Future research should explore how these predictors vary across different demographic groups and cultural contexts.Psychology, Department ofHonors Colleg
Unveiling Legacy: Black Women's Leadership in the Black Campus Movement
No full textThis research project highlights the contributions of Black women within the Black Campus Movement of the late 1960s, which improved systemic conditions for marginalized communities within collegiate institutions. Utilizing archival research and literary review of works such as Ibram X. Kendi's Black Campus Movement: The Racial Reconstruction of Higher Education, 1965-1972, and Lauren Araiza's Black Power and the Mills Girls: Gender and the Black Campus Movement at Mills College, 1967-69 this work aims to articulate the significance of Black women's authority throughout this period. The research findings are organized into a digital archival exhibit, where protest records, administrative correspondence, newspaper clippings, and documentation of student demands provide a comprehensive view of the legacy of Black women's leadership. This project underscores the contributions of student activists Rosemary Freeman at the University of Minnesota and the Black Students' Union at Mills College, illustrating how their advocacy catalyzed institutional reform within their respective institutions while affirming the presence of Black women within the historical narrative of activism.African American Studies, University of HoustonHonors Colleg
Spleen-Targeted Lipid Nanoparticles in the Treatment of Autoimmune Diseases
No full textAutoimmune diseases, once considered rare, now affect 3–5% of the global population according to recent epidemiological studies. The complex mechanisms underlying these diseases present significant challenges for researchers. Traditional treatments have relied on immunosuppressive drugs, which, despite their effectiveness, lack specificity and often cause severe side effects. This has driven a shift towards developing targeted therapies. Nucleic acid-based therapeutics have gained increasing attention for their potential to address diseases at the genetic level. Lipid nanoparticles (LNPs) have emerged as a superior delivery system for these therapeutics due to their biocompatibility, biodegradability, and efficient encapsulation capabilities. Given the spleen's pivotal role in immune processes, this study comprises two main projects aimed at developing spleen-targeted LNPs in the treatment of autoimmune diseases. The first project involves utilizing spleen-targeted LNPs encapsulating disease-specific antisense oligonucleotides (ASOs) to mitigate autoimmune phenotypes in an autoimmune mouse model. Spleen-targeted LNPs were developed and characterized for their size, polydispersity index (PDI), and encapsulation efficiency, with their spleen-targeting behavior evaluated via in vivo imaging and their knockdown efficiency assessed through western blotting and flow cytometry. Therapeutic effects on spleen-related autoimmunity were comprehensively analyzed, including immune cell populations, autoantibody levels, cytokine profiles, and disease-related protein expressions, with therapeutic effects extending to other tissues due to decreased IgG deposition, resulting in alleviated proteinuria and neuropsychiatric deficits. The second project focuses on developing mannosylated spleen-targeted LNPs with enhanced transfection efficiency. In this study, mannose was introduced to LNPs to target receptors abundantly expressed on macrophages and dendritic cells, which are important cell subsets for maintaining immune homeostasis and crucial for endocytosis. The prepared LNPs demonstrated uniformity, elevated in vitro transfection efficiency, spleen-targeting activity, and enhanced transfection efficiency in the spleen. Flow cytometry confirmed their high uptake by antigen-presenting cells. Overall, these studies explored the potential of spleen-targeted LNPs for nucleic acid delivery and peripheral immune system modulation, presenting an innovative approach to treating autoimmune diseases
Using C. elegans to Observe the Gut Microbiome Response to Antibiotics in the Context of C. difficile
No full textClostridium difficile is a gram-positive spore forming bacterium that colonizes the gut and infects the colon. C. difficile infection and colonization of the gut microbiome has been linked to antibiotic susceptibility. This project uses Caenorhabditis elegans to establish a model and method of research of the impact of antibiotics on the gut microbiome in the context of CDI. It establishes the necessary procedure to culture, strain, and synchronize C. elegans. A toxin and microbiome assay were conducted utilizing grown C. difficile spores and 10 different CeMbio microbiome species, designed to mimic the wild C. elegan microbiome. The worms were stained using DAPI, a type of nucleic acid dye, and visualized under a microscope. This research introduces a new method for studying CDI. Techniques such as synchronization of C. elegans, feeding them C. difficile toxins and CeMbio microbiota, and assessing microbiome impacts were developed. A control for C. difficile toxin colonization of the gut was established, enabling the potential for further research on antibiotic susceptibility and indicating that alteration of the microbiome impacts the worm fitness in the context of CDI. Initial results for a defined microbiome for C.elegans using CeMbio were established, with some strains growing more efficiently than others. DAPI staining experiments can be utilized with stain specific primers to perform PCR tests that observe gut microbiome bacterial diversity. This project asserts C. elegans as a viable model for C. difficile research and develops the groundwork for more comprehensive studies of C. difficile-antibiotic interactions within the gut microbiome. [This project was completed with contributions from Lauren Elizabeth Matus from the University of Texas at Austin.]Pharmacy Practice and Translational Research, Department ofHonors Colleg
Application of Criteria for Hydrogen Transportation Refueling for Several Countries Considering Energy Resource and Use Implications
No full textThe transition to hydrogen-based transportation requires strategic evaluation of energy sources, infrastructure, and regional capabilities. This study investigates the feasibility of hydrogen refueling for ground transportation by implementing the established criteria for transitioning from conventional fuels to hydrogen. The United States and the United Kingdom serve as base case studies for defining six primary criteria: feedstock, production, storage, distribution, end-use applications, and policy considerations, including government incentives and public perception. These criteria are then applied to seven additional countries Japan, France, Nigeria, South Africa, Germany, South Korea and China to test their adaptability across diverse geopolitical and energy contexts. The analysis provides a comparative assessment of hydrogen implementation strategies, focusing on technological pathways, environmental impact, economic viability, and infrastructure readiness. Furthermore, the study incorporates Technology Readiness Levels (TRLs) to evaluate the maturity of hydrogen systems within each country. The results highlight significant variation in hydrogen mobility potential due to differences in energy resource availability, infrastructure development, and policy frameworks. Countries with strong renewable energy portfolios and supportive regulatory environments exhibit greater readiness for hydrogen adoption. Conversely, regions lacking cohesive policy or infrastructure face steeper barriers to implementation. Overall, this research offers a structured, criteria-based framework to support decision-makers in designing context-specific hydrogen transportation strategies. It contributes to ongoing efforts in decarbonizing the transportation sector and provides a foundation for future investment and policy development in the global hydrogen economy