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Student Narratives of Inquiry-Based Introduction to Proof Courses
Get PDFThis dissertation explores how undergraduate students’ identities shape their experiences in inquiry-based Introduction to Proof (ITP) courses. As more institutions implement active learning strategies in mathematics, inquiry-based mathematics education (IBME) is promoted as a pathway to deepen engagement and promote equity. However, research shows that active learning environments, including IBME, do not automatically produce equitable outcomes. This qualitative study employs narrative inquiry to investigate the experiences of 12 students enrolled in two ITP courses at a Hispanic-serving institution. Drawing on identity theory (Gee, 2000), positioning theory (Harré & Langenhove, 1999), and mathematics identity frameworks (Larnell, 2016; Martin, 2006), the study investigates how students’ identities influence their self-positioning, perceptions of peers, participation patterns, and interpretations of classroom norms. Data were collected through two rounds of semi-structured interviews and reflective journals. Findings illustrate the complex, evolving nature of students’ math identities and the ways these identities intersect with classroom norms and personal histories. Some students experienced affirmation and growth in the inquiry-based setting, while others struggled with visibility, belonging, or the expectations embedded in classroom participation norms. Patterns in peer interactions, instructor positioning, and perceived competence emerged as key factors in shaping participation and engagement. The dissertation highlights the importance of attending to students’ lived experiences and sense-making when evaluating the equity of inquiry-based learning environments. This work contributes to the field by offering narrative evidence of how inquiry-based instruction both supports and constrains student identity development. Implications include strategies for fostering inclusive participation norms, validating diverse mathematical identities, and creating learning environments that support all students, not just those who already feel a sense of belonging.Mathematic
Texas Librarians Communicate Their TSLAC Experiences and Future Needs and Dreams for Texas Libraries and Communities
Get PDFThis report documents the results of an applied communication research project that examined how Texas librarians, library directors, and library staff utilize resources, programs, trainings, and web materials from the Texas State Library and Archives Commission (TSLAC). As researchers with the Translational Health Research Center at Texas State University, we partnered with TSLAC staff to invite Texas librarians to participate in our confidential questionnaire and individual interview research about their experiences with TSLAC and overall library resources, programs, and outreach needs.
We utilized applied Communication Studies lenses to analyze questionnaire data from 112 participants and individual interviews with 40 participants to examine librarians’ communication about TSLAC resources and programs. Our report: provides a snapshot of participants' experiences, libraries, and demographics; details how participants use TSLAC resources and programs; documents needs and improvements for future TSLAC offerings; imagines future programs for libraries and communities in Texas and across the United States; and visualizes librarians' fears, hopes, and dreams for libraries to best support their communities. We end with our top twelve recommendations for TSLAC and other organizations and groups seeking to support libraries, librarians, and their communities
Describing the Cell Biology of Saprolegnia parasitica: Role of Metals and Respiration
No full textSaprolegnia parasitica is a pathogenic oomycete that causes saprolegniasis, a serious disease affecting freshwater fish and aquaculture systems. Despite the increasing use of copper-based treatments to control this infection, little is known about how S. parasitica responds to fluctuations in metal availability at the physiological and mitochondrial levels. This study investigates the impact of copper and iron availability on Saprolegnia parasitica growth, metal uptake, and respiratory function. We cultured S. parasitica in chemically defined media supplemented with or depleted of essential metals using specific chelators— Bathocuproinedisulfonic acid (BCS) (a high-affinity Cu(I) chelator), Ferrozine (Fe(II)), and BPS (Fe(II)). Growth responses were assessed via biomass measurements, while intracellular metal content was quantified using inductively coupled plasma mass spectrometry (ICP-MS). Interestingly, BCS treatment did not significantly inhibit growth or reduce copper content compared to control growth conditions, suggesting that S. parasitica may bypass extracellular copper chelation through alternative uptake pathways or internal copper reservoirs. To assess mitochondrial function, we measured Saprolegnia parasitica oxygen consumption using a Clark-type oxygen electrode under varying growth conditions. BCS-treated S. parasitica maintained respiration rates similar to the untreated controls, with a sustained contribution from the alternative oxidase (AOX) pathway, even under copper-limited conditions. These results indicate a possible shift in electron transport chain dynamics, allowing S. parasitica to maintain mitochondrial function when cytochrome c oxidase (CcO) is compromised by metal limitation.
Overall, this study provides novel insights into the adaptive mechanisms employed by S. parasitica to overcome metal deprivation. The ability to maintain respiration through AOX and resist copper chelation suggests that targeting metal homeostasis may require more nuanced strategies in the management of saprolegniasis. Results revealed that S. parasitica modulates growth and respiration in relation to environmental metal concentrations, with specific uptake mechanisms contributing to metal homeostasis. These findings highlight the importance of metal bioavailability in regulating the pathogen’s physiology and may inform approaches to limit its spread in aquaculture systems by manipulating environmental conditions or targeting metal acquisition pathways.Chemistry and Biochemistr
Oral history interview: Kile West
No full textEdited and unedited transcript files (.pdf) and edited and unedited video files available with closed captioning.Oral history interview with Nanette West about her son, Kile West
Effects of Preoperative Exercise Interventions in Patients Undergoing Metabolic and Bariatric Surgery: A Systematic Review and Meta-Analysis
No full textBackground: Obesity affects over one billion people globally. Bariatric surgery is the most effective long-term intervention for severe obesity. However, postoperative outcomes can vary considerably, with such factors as baseline fitness and cardiorespiratory reserve influencing surgical outcomes. This systematic review aimed to evaluate the effects of preoperative exercise or physical activity, compared to standard care or no intervention, on preoperative fitness parameters and perioperative surgical outcomes in adults with obesity undergoing metabolic and bariatric surgery. Methods: A systematic review was conducted in accordance with the recommendations of the Cochrane Handbook and the PRISMA guidelines. Randomized controlled trials, non-randomized controlled trials, and cohort studies with control groups evaluating preoperative exercise interventions were included. Two independent reviewers conducted study selection, data extraction, and risk of bias assessment using Cochrane tools. Meta-analyses were performed using random effects models, with standardized mean differences calculated for continuous outcomes. Evidence certainty was assessed using the GRADE approach. Results: A total of 15 studies, including 1378 participants, were identified for qualitative synthesis, with 12 contributing data for quantitative meta-analysis. Preoperative exercise interventions significantly improved six-minute walk test distance (SMD 2.01; 95% CI: 0.51 to 3.50; p = 0.009) and VO2 peak (SMD 1.02; 95% CI: 0.52 to 1.51; p < 0.0001). BMI reduction was significant (SMD −0.96; 95% CI: −1.75 to −0.16; p = 0.02), while weight change was not statistically significant (SMD −0.81; 95% CI: −1.72 to 0.09; p = 0.08). One study reported a reduction in hospital length of stay of 0.64 days (95% CI: −0.86 to −0.42; p < 0.00001). Evidence certainty was rated as very low to low across all outcomes. Conclusions: Preoperative exercise interventions have been shown to significantly improve cardiorespiratory fitness in bariatric surgery candidates, with large effect sizes for functional capacity measures. Despite the low certainty of the evidence, these findings suggest that supervised exercise programs should be incorporated into the preoperative care of bariatric surgery patients.Division of Researc
Neurobiological and Microbiota Alterations After Bariatric Surgery: Implications for Hunger, Appetite, Taste, and Long-Term Metabolic Health
No full textBariatric surgery (BS) is an effective intervention for obesity, inducing significant neurobiological and gut microbiota changes that influence hunger, appetite, taste perception, and long-term metabolic health. This narrative review examines these alterations by analyzing recent findings from clinical and preclinical studies, including neuroimaging, microbiome sequencing, and hormonal assessments. BS modulates appetite-regulating hormones, reducing ghrelin while increasing glucagon-like peptide-1 (GLP-1) and peptide tyrosine-tyrosine (PYY), leading to enhanced satiety and decreased caloric intake. Neuroimaging studies reveal structural and functional changes in brain regions involved in reward processing and cognitive control, contributing to reduced cravings and altered food choices. Additionally, BS reshapes the gut microbiota, increasing beneficial species such as Akkermansia muciniphila, which influence metabolic pathways through short-chain fatty acid production and bile acid metabolism. These findings highlight the complex interplay between the gut and the brain in post-surgical metabolic regulation. Understanding these mechanisms is essential for optimizing post-operative care, including nutritional strategies and behavioral interventions. Future research should explore how these changes impact long-term outcomes, guiding the development of targeted therapies to enhance the recovery and quality of life for BS patients.Division of Researc
Spatial Variation and Environmental Drivers of Mercury in Caddisflies (Trichoptera) in the Colorado River Basin
No full textNo abstract prepared.Biolog
Rigor and Reproducibility: pH Adjustments of Papain with L-Cysteine Dissociation Solutions and Cell Media Using Phenol Red Spectrophotometry
No full textPhenol red is a widely used, low-cost, label-free colorimetric pH indicator that bridges traditional colorimetric assays with modern quantitative imaging and cell-based screening platforms. Its protonation-dependent absorbance shift (430–560 nm) allows for the real-time monitoring of extracellular acidification, which indirectly reflects cellular metabolism, growth, and respiration. Although phenol red lacks the molecular specificity of genetically encoded or fluorogenic biosensors, it remains useful in systems where pH changes are effective proxies for physiological processes. Existing tissue digestion protocols often overlook key parameters, especially pH control and enzyme cofactor use. This study presents a straightforward, spectrophotometric method to monitor and adjust the pH of low-volume (1 mL) buffered enzymatic dissociation media using phenol red and a plate reader. We titrated dissociation solutions to physiological pH (~7.4) using spectrophotometric pH measurements validated against conventional glass pH probe readings, confirming method reliability. Accurate pH assessment is critical for isolating viable primary cells for downstream applications such as tissue engineering, single-cell omics, and neurophysiological assays. We highlight that papain-based dissociation media supplemented with L-cysteine can be acidic (pH 6.6) if unadjusted, compromising cell viability. This accessible approach enhances reproducibility by promoting pH documentation concerning dissociation conditions that contribute to advancing consistency in biomedical, cellular, neuronal, and tissue engineering research.Biolog
Enhancing Wearable Fall Detection System via Synthetic Data
No full textDeep learning models rely heavily on extensive training data, but obtaining sufficient real-world data remains a major challenge in clinical fields. To address this, we explore methods for generating realistic synthetic multivariate fall data to supplement limited real-world samples collected from three fall-related datasets: SmartFallMM, UniMib, and K-Fall. We apply three conventional time-series augmentation techniques, a Diffusion-based generative AI method, and a novel approach that extracts fall segments from public video footage of older adults. A key innovation of our work is the exploration of two distinct approaches: video-based pose estimation to extract fall segments from public footage, and Diffusion models to generate synthetic fall signals. Both methods independently enable the creation of highly realistic and diverse synthetic data tailored to specific sensor placements. To our knowledge, these approaches and especially their application in fall detection represent rarely explored directions in this research area. To assess the quality of the synthetic data, we use quantitative metrics, including the Fréchet Inception Distance (FID), Discriminative Score, Predictive Score, Jensen–Shannon Divergence (JSD), and Kolmogorov–Smirnov (KS) test, and visually inspect temporal patterns for structural realism. We observe that Diffusion-based synthesis produces the most realistic and distributionally aligned fall data. To further evaluate the impact of synthetic data, we train a long short-term memory (LSTM) model offline and test it in real time using the SmartFall App. Incorporating Diffusion-based synthetic data improves the offline F1-score by 7–10% and boosts real-time fall detection performance by 24%, confirming its value in enhancing model robustness and applicability in real-world settings.Computer Scienc
Oral history interview: Polo Cardenas
No full textEdited and unedited transcript files (.pdf) and edited and unedited video files available with closed captioning.Oral history interview with Janice Elliott about her daughter's father, Polo Cardenas