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Self-Driving Laboratories for Autonomous Discovery of New Materials
No full textRapid discovery of efficient electrocatalysts is a cornerstone in the advancement of sustainable energy technologies such as water electrolysis. However, conventional trial-and-error experimental workflows are slow, labor-intensive, and poorly suited for exploring vast compositional spaces. This thesis presents the design and implementation of a fully automated, modular self-driving laboratory system capable of autonomously synthesizing and characterizing multi-metallic catalysts for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). The system integrates mechanical, electronic, and software components in a tightly orchestrated workflow. Python-controlled SCARA robotic arms perform all experimental steps—including precursor mixing, electrode loading, deposition, rinsing, and evaluation—without human intervention aside from periodic replacement of consumables like stock solutions and electrode substrates. Mechanically, the platform features a 3D-printed, custom-designed interchangeable working electrode holder for stainless steel mesh substrates, as well as modular reservoir stands. A single-layer PCB, etched and fabricated in-house, connects to 11 electrode holders to a CHI 660E single- channel potentiostat via magnetic contacts, enabling sequential electrochemical processing. The electrochemical deposition and evaluation of binary and ternary catalysts— including NiFe, NiFeCo, and NiMoP systems—are conducted in 1 M KOH. Techniques such as cyclic voltammetry (CV), chronoamperometry/chronopotentiometry (CP), and iii electrochemical impedance spectroscopy (EIS) are used to assess catalyst performance. Electrodes are automatically rinsed in deionized water between steps, and simple optical inspection is enabled via robotic positioning in front of a fixed zoom camera. Experimental data are collected and processed by a custom Python pipeline that performs iR correction, extracts relevant metrics (e.g., overpotential at 10 mA/cm² for OER, potential at 10 mA/cm² for HER, and resistance at zero phase from EIS), and generates comparative plots across compositional ratios. Ternary compositional maps are used to visualize performance trends and guide further testing. Although all workflows are currently driven by user-defined parameters, the platform is designed for future integration with machine learning frameworks—such as Graph Neural Networks (GNNs) or Bayesian Optimization—to enable closed-loop, data-driven catalyst optimization. By combining autonomous robotics with scalable electrochemical analysis and modular hardware design, this work lays a robust foundation for accelerated discovery and screening of electrocatalysts using self-driving lab methodologies
RETRACTED: Sabbagh et al. Evaluation and Classification Risks of Implementing Blockchain in the Drug Supply Chain with a New Hybrid Sorting Method. Sustainability 2021, 13, 11466
No full textThe journal retracts the article titled “Evaluation and Classification Risks of Implementing Blockchain in the Drug Supply Chain with a New Hybrid Sorting Method” [...
Biochar for Soil Amendment: Applications, Benefits, and Environmental Impacts
No full textThe excessive use of chemical fertilizers results in environmental issues, including loss of soil fertility, eutrophication, increased soil acidity, alterations in soil characteristics, and disrupted plant&ndash;microbe symbiosis. Here, we synthesize recent studies available from up to 2025, focusing on engineered biochar and its application in addressing issues of soil nutrient imbalance, soil pollution from inorganic and organic pollutants, soil acidification, salinity, and greenhouse gas emissions from fields. Application of engineered biochar enhanced the removal of Cr (VI), Cd<sup>2+</sup>, Ni<sup>2+</sup>, Zn<sup>2+</sup>, Hg<sup>2+</sup>, and Eu<sup>3+</sup> by 85%, 73%, 57.2%, 12.7%, 99.3%, and 99.2%, respectively, while Cu<sup>2+</sup> and V<sup>5+</sup> removal increased by 4 and 39.9 times. Adsorption capacities for Sb<sup>5+</sup>, Tl<sup>+</sup>, and F<sup>&minus;</sup> were 237.53, 1123, and 83.05 mg g<sup>&minus;1</sup>, respectively, and the optimal proportion of polycyclic aromatic hydrocarbon (PAH) removal was 57%. Herbicides such as imazapyr were reduced by 23% and 78%. Low-temperature pyrolyzed biochar showed high cation exchange capacity (CEC) resulting from improved surface functional groups. Although biochar application led to a yield increase of 43.3%, the biochar&ndash;compost mix enhanced it by 155%. The analysis demonstrates the need for future studies on the cost-effectiveness of biochar post-processing, large-scale biochar aging studies, re-application impact, and studies on biochar&ndash;compost or biochar&ndash;fertilizer mix productivity
Elastic Cytomatrix Dynamics Influences Metabolic Rate and Tumor Microenvironment Formation
No full textIn healthy cells, the cytomatrix mechanics utilize mitochondrial respiration to control cytosolic motion and fine-tune the chemical processes. In cancer, the cytosolic motion is energized by glycolytic fermentation (the Warburg effect), which provides additional energy to supply the needs of the cytomatrix. Here, we describe the physical and chemical processes of the integrated and cooperative cytomatrix cytoarchitecture, in which structure and function are inseparable. The extracellular matrix is interconnected with the intracellular cytomatrix and functions as two integrated elastic solid phases. This finding led us to propose mechanisms of tumor microenvironment formation resulting from the mutational burden, in which altered proteins with corresponding post-translational modifications translocate to the cell surface, where they attract immunocompetent cells and activated fibroblasts, producing a tumor-insulating niche. This insulation disrupts cell-to-cell recognition and other signaling pathways that affect the intracellular cytomatrix, particularly actin dynamics, which influence both cell size and shape, recognized as the dedifferentiated state of cancer cells. We also discuss the perspectives of AI in cytomatrix modeling and neural network modeling, focusing on the effects of intracellular and extracellular matrices on the development of the tumor microenvironment
Zeolite Crystallization: Using Parametric, Mechanistic, and Data Driven Approaches to Control the Formation of Optimized Zeolite Catalysts
No full textZeolite crystallization predominately occurs by nonclassical pathways involving the attachment of complex (alumino)silicate precursors to crystal surfaces, yet recent images of fully crystalline materials with layered surfaces comprised of nanometer-sized steps are evidence that growth also occurs by classical route of molecule (monomer) attachment. Visualization of zeolite crystal growth is challenging due to the nature of zeolite synthesis, which requires high temperature, high alkalinity, long synthesis time, and different types of amorphous precursors exist throughout the entire crystallization process. In this work, we used high temperature solution phase atomic force microscopy to study the crystallization of zeolite under in-situ conditions. We discovered a unique 3-demonsional growth mechanism for zeolite FAU. It also showed the dominance of gel mediated crystal growth in the case of FAU synthesis, which is one step further in understanding the relationship between solution and solid phase in the synthesis of FAU crystals. The in-situ AFM results emphasized the importance of solid phase in FAU crystallization, so based on this discovery, we wanted to use FAU crystal as the seed to design other zeolite materials. Seed-assisted synthesis can impact zeolite properties such as size, morphology, structure, and defects. We observed that the chemical structure of organic structure-directing agents (OSDAs) plays a significant role in controlling the kinetics of nucleation and the trajectory of interzeolite transformations. Furthermore, we observed that the hydrothermal stability of zeolite catalysts can be strongly impacted by the defective intermediates during the synthesis process. Advantages of using optimal OSDA included shorter synthesis time and the ability to reduce or eliminate the defective intermediates, thereby providing a facile and efficient route to design zeolites for various industrial applications. The fundamental mechanisms underlying defective intermediates during zeolite crystallization are complex and elusive; however, our study provides new insight into these processes and highlights the important rile of kinetics in governing the parent-daughter (or seed-product) relationships. This approach can be used to upgrade the performance of commercial catalysts and serve as a generalized platform for the rational design of zeolite across a broad range of zeolite frameworks for various applications
The Impact of Cardiorespiratory Fitness, Exercise, and Exercise Intensity on the Function and Metabolism of Regulatory T Cells
No full textRegulatory T cells (Tregs) suppress excessive immune activity, which is crucial for promoting immune tolerance and preventing autoimmunity. Treg functional activity is tightly linked to their cellular metabolic activity. Although Treg function and metabolism are increasingly recognized as key factors in immune balance, little is known about how they are influenced by exercise or by cardiorespiratory fitness (CRF). Acute exercise mobilizes Tregs and increases the production of anti-inflammatory cytokines like interleukin (IL)-10. However, Treg metabolic responses to CRF, acute exercise, and exercise intensity have not been characterized. This study addressed these gaps by investigating i) whether CRF is associated with Treg function and metabolism, and ii) how acute exercise at different intensities affects Treg function and metabolism in healthy adults. Participants (n=45: 18 female; 29.8 6.26 years) completed a VO2max test and resting blood samples were obtained to assess the relationship between CRF and Treg function and metabolism. After VO2peak assessment, those of moderate fitness (n=18; 9 female; 29.22 6.90 years, 33.80 3.93 ml/kg/min VO2peak) completed two additional exercise bouts involving 30-minutes of cycling at a moderate (90% VT1) and heavy (110% VT1) intensity. Blood samples were collected at pre-, post-, and 2 hours post-exercise to assess how acute exercise and its intensity impacts Treg function and metabolism. Linear regression revealed VO2peak was positively correlated with glycolytic capacity and negatively correlated with mitochondrial dependence (both: R2 = 0.116; F(1, 43) = 5.655; p= 0.022). Linear mixed models revealed both metabolic activity (F(2, 83.083)= 6.690; p= 0.002) and glycolytic capacity (F(2, 80.428)= 6.277; p= 0.003) decreased post-exercise while mitochondrial dependence increased post-exercise (F(2, 80.428)= 6.277; p= 0.003). The number of IL-10+ Tregs (F(2, 76.224)= 4.913; p= 0.010) and IL-10 MFI of Tregs (F(2, 74.046)= 4.193; p= 0.019) was greater 2 hours post-exercise compared to pre-exercise. Intensity did not impact Treg function but had an interaction effect on Treg glucose dependence and FAO/AAO capacity post-exercise in the heavy intensity bout. In summary, this study provides the first evidence that CRF is linked to greater Treg mitochondrial dependence and lower glycolytic capacity and lower mitochondrial dependence. Acute exercise transiently enhanced Treg mitochondrial dependence and suppressed glycolytic capacity, supporting the role of exercise as a modifiable factor in shaping Treg metabolic responses
The Effects of Muscle Synergy-Guided Exercise on Spinal Motoneuronal Activation in Stroke: A Pilot Study
No full textStroke is a leading cause of neuromuscular disorder and causes the loss of intermuscular coordination. Muscle synergy analysis is a method of observing the neuromuscular state of stroke survivors through the co-activation of muscles. By using muscle synergy analysis, nuanced methods for diagnosis and rehabilitation can be achieved, offering strengthened intermuscular coordination and decreasing involuntary muscle co-activation. However, little is known about how utilizing muscle synergy in developing neurorehabilitative exercise can affect a stroke patient on the level of motoneuronal activity along the spine. By using a quantitative model known as spinal maps, I evaluated spinal activity to observe the effects of synergy-guided rehabilitation on motoneuronal pools in stroke. In this longitudinal pilot study, synergy-guided training involved training three chronic stroke survivors with varying severity in motor impairment: mild, moderate, and severe based on the Fugl-Meyer upper extremity (FMA-UE) score. Participants were trained to match four targeted synergistic muscle coordination patterns over six weeks. Electromyographic data for the Elbow Flexion and Elbow Extension synergy targets were collected and processed before and after the training period for computing spinal maps. To observe the effects of synergy-guided training, the properties of spinal maps were quantified into two metrics, center of activity (CoA) and skew, which captured changes in distribution such as the localization of motoneuronal activity and overall motoneuronal spread along the spine. CoA and skew showed shifts based on the synergy target. For the Elbow Flexion synergy target, the center of activity and skew showed the motoneuronal activity to shift towards the C5/C6 region with a more expected distribution. In the case of Elbow Extension, the distribution for two out of three participants shifted towards Elbow Extension region after training, represented by the C7/T1 segments, and one out of three showed a shift in skew towards the target distribution. These shifts in the distribution could only occur if involuntary muscle co-activation showed a decrease and spinal motoneuronal activity became more localized within specific segments of the spine. Overall, the findings from this study suggest that spinal maps can provide additional insights into the effects of synergy guided training on the changes in the spinal motoneuronal activities in strokes
Evaluating SAT Score Gains in Aspire Students: Does Pre-/Post-test Format Matter?
No full textOnly 23% of Houston Independent School District (HISD) seniors meet the College Board's SAT benchmark for college and career readiness. To address this gap, Aspire provides free SAT tutoring and post-secondary preparation to students at Austin High School, a predominantly Hispanic, low-income urban high school in HISD. This study examines whether Aspire students' SAT score improvements vary based on the format of their pre- and post-program exams. Data from participants across nine semesters (N=95) were categorized into four groups based on students' pre-/post-test format: Diagnostic/PSAT, Diagnostic/SAT, PSAT/SAT, and SAT/SAT. Statistical analysis indicated a significant diagnostic advantage: students whose pre-program scores were derived from Aspire diagnostic tests exhibited significantly greater score gains than those with prior official PSAT or SAT scores (p<0.001). Additionally, students who transitioned from a diagnostic to the PSAT demonstrated greater score improvements than those who transitioned directly to the SAT (p<0.01). These findings suggest that Aspire is most effective as an early intervention, before students develop ingrained test-taking habits or fixed perceptions of their abilities. If this is the case, recruitment may be better focused on sophomores and juniors rather than upperclassmen to maximize mentee success. Future research should explore how the SAT's recent transition to a digital, adaptive format affects student outcomes and how Aspire's curriculum can evolve to maintain its impact. Understanding these changes can help refine Aspire's approach, allowing the program to better serve students and reduce educational disparities in under-resourced communitiesHonors Colleg
The Impact of Climate Change on Soil Microbial Ecosystems
No full textMicrobial communities play a critical role in supporting plant responses to environmental stresses, such as drought. While microbes aid in nutrient cycling and stress tolerance, the impact of drought on the diversity of soil microbial communities within plant ecosystems remains less understood. Understanding this microbial diversity under drought conditions is essential for enhancing plant resilience and promoting sustainable agricultural practices. This study aims to assess how drought conditions influence plant-associated microbial communities and their effects on plant growth. We hypothesize that drought will reduce microbial diversity, consequently impairing plant growth and resilience. By filling this knowledge gap, this research will provide insights into optimizing plant-microbe interactions for sustainable food systems under changing environmental conditions.Biology and Biochemistry, Department ofHonors Colleg
The Role of Reminiscence in Identity Construction Among Chinese American Emerging Adult Women
No full textBackground: Chinese American emerging adults, defined as adults between 18-29, are a large and growing sector of the population who face the challenge of constructing adult identities while facing major life transitions and living in a highly racialized society. Although contemporary perspectives suggest that reminiscence might be a key factor in this process, few studies have examined how reminiscence affects identity development for Chinese American women in this age range. Without such research, clinicians and other providers have little to guide intervention with this population. Purpose: Given this background, the current study aimed to understand how Chinese American emerging adult women construct identity through reminiscence. Methods: Ten Chinese American emerging adult women between the ages of 18-29 were interviewed on their memories, reminiscence processes, and identity development. Transcripts were analyzed with grounded theory methods. Results: Four core categories emerged from the data (social and historical context surrounding Chinese American womanhood, memories of Chinese American emerging adult women, process of reminiscence, and memory-sharing as a method of identity construction). These findings contribute to a grounded theory that suggests Chinese American women establish narrative identities during emerging adulthood through reminiscence by retrieving memories and making meaning of them within their present context. In this sense, reminiscence functions as an iterative process in which participants are integrating and re-integrating their personal narratives to find continuity and develop a personal identity of Chinese American womanhood. This use of reminiscence as a key process for identity construction occurred in reaction to the dehumanizing and stereotyped narratives attributed to Chinese American women and allowed participants to construct nuanced narratives to contradict societal narratives. Conclusion: Reminiscence is an essential contextual, social process that Chinese American emerging adult women use to make sense of their identities in response to stereotyped and dehumanizing narratives from U.S. society. Therefore, understanding the full psychological impact of reminiscence requires looking beyond the psychological functions of reminiscence and exploring how reminiscence (a) stabilizes and deepens an individual’s understanding of identity, (b) recovers and reinterprets memories within the present context, and (c) allows individuals to share their narratives with others to establish social identities