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John Bickham field notebook: AK3501-AK4000.pdf
No full textBound book, each page corresponds to a karyotype slide data.Data pages for AK4001-AK4500 corresponding to unique identifiers of specimens/samples examined for biological research. Specimens are primarily housed at Texas A&M University; Biodiverstiy Research and Teaching Collection
Latinx Individuals in US Sport
No full textThe dissertation central objective is to critically examine the underrepresentation of Latinx individuals in the realm of the United States (US) sport landscape. Commencing with Study 1, a meticulous scoping review of literature was undertaken, revealing a conspicuous research gap spanning four decades, particularly in the context of Latinas in sport. Significantly, 74.1% of the studies surveyed relied on quantitative methodologies, shedding light on the imperative for broader research methods to unravel the intricate dimensions of experiences within this population.
Study 2, grounded in Latin Critical Race Theory (LatCrit), investigated micro and meso-level factors affecting Latinx student-athletes in Predominantly White Institutions (PWI). Despite Diversity, Equity, and Inclusion (DEI) interventions, participants reported encountering racial biases from athletic staff and peers, relying on familial support and campus resources to address these issues. The outcomes underscore the urgent need for initiatives to mitigate disparities faced by Latinx student-athletes.
Subsequently, Study 3 sought to comprehend macro-level experiences of Latinx individuals, undocumented populations, and DACA recipients in the US, with a specific focus on sports participation and community engagement. Grounded in Critical Race Theory (CRT) and Sport for Development and Peace Theory (SFDT), the data collection phase extended over 13 weeks within a Houston, Texas community. Findings illuminated the challenges confronting DACA holders and undocumented individuals in assimilating into new communities, with community-oriented programs identified as pivotal catalysts for positive change.
In conclusion, the dissertation rigorously examines the limitations, theoretical contributions, practical implications, and future trajectories emanating from the tripartite studies. Emphasizing the imperative for diverse research methodologies, it underscores the urgency of addressing racial biases in PWIs and accentuates the pivotal role of community programs in facilitating integration for Latinx individuals, DACA recipients, and undocumented populations within the sporting milieu
Genetic Ablation of PITPNC1 Impairs Proliferation and Tumor Growth in Murine Melanoma via Mitochondrial Dysregulation
No full textPhosphoinositides (PIPs), the phosphorylated derivatives of phosphoinositols (PtdIns) are critical for eukaryotic cellular signaling. Major dysregulation of PIP signaling pathways has catastrophic effects, as subtle changes can cause neurodegenerative diseases and cancer in mammals. In this context, studying phosphatidylinositol transfer proteins (PITPs) urges our interest. Recent studies have indicated an important role for PITPs in determining the biological outcomes of PIP signaling, via a novel mechanism in which they likely do not function as lipid carriers.
PITPNC1, a member of under-investigated mammalian phosphatidylinositol transfer proteins (PITPs), is overexpressed in several metastatic tumors, including breast, colon, pancreatic, and melanoma. The tumor suppressor micro-RNA miR-126 also identifies PITPNC1 as a crucial target, of disease relevance. However, to date, no studies have emphasized the role of PITPNC1 in a complete knockout and immunocompetent environment. This has left critical gaps in understanding the role of protein in the signaling and metabolism of cancer cells and addressing these issues remain our primary focus. Our research demonstrates that PITPNC1 knockout mice are born alive and do not display overt phenotypes. However, phenotypic characterization of PITPNC1-/- mouse reveals changes in body fat and non-shivering thermogenesis in the females. PITPNC1 is associated with reduced patient survivability in melanoma cancer and its expression correlates with metastatic progression in murine and human melanoma cells. To understand the role of PITPNC1 in the context of melanoma, we employed a syngeneic murine melanoma model in which B16 melanoma cells were introduced to immunocompetent mice by subcutaneous injection. We demonstrated that PITPNC1 overexpression promotes tumor growth and metastasis in melanoma tumors. In addition, CRISPR-Cas9 generated PITPNC1 knock-out melanoma cells inhibit melanoma cancer progression in vivo in both non-cell-autonomous and cell-autonomous manner. Next, our findings indicate that PITPNC1 deletion alters the lipidomic profile in B16F10 melanoma cancer with loss of PIP3 lipid and cholesterol esters and accumulation of acylcarnitine and triglycerides, suggesting compromised fatty acid oxidation, which potentially underlies mitochondrial dysregulation in the PITPNC1 null condition. Lastly, we demonstrated that PITPNC1 null cells have a defective mitochondrial function with increased mitochondrial fragmentation in B16F10 melanoma cells. In this study, we conclude that PITPNC1 overexpression promotes tumor metastasis while genetic ablation of PITPNC1 impairs tumor growth in murine melanoma via mitochondrial dysregulation
Non-Intrusive Wearable Accelerometry for Early Detection and Monitoring of Chronic Diseases and Mental Health Issues
No full textChronic diseases and mental health issues account for a majority of deaths worldwide. Neuropsychiatric illnesses are a considerable component of this global health burden. Therefore, there is a need for early detection and continuous monitoring of neuropsychiatric illnesses, such as stress, Parkinson's disease, bipolar disorder, and hypoglycemia in patients with diabetes. Traditional monitoring methods, such as medical history, physical examinations, and laboratory tests, have several challenges due to their invasive nature, cost, and continuous monitoring issues.
Wearable technology offers a promising alternative to the traditional methods. Accelerometers, in particular, can provide a non-intrusive, cost-effective, and easy-to-integrate solution suitable for large-scale use. Acceleration data can be combined with machine learning models to provide insights into chronic diseases and mental health issues. Despite the benefits of accelerometer sensors, the use of acceleration data alone has remained unexplored, or it has been used with other physiological data such as heart rate in current literature.
In this dissertation, I study the potential of wearable accelerometer data to detect chronic diseases and mental disorders. In Chapter 1, I review the existing literature that used acceleration data to identify chronic diseases and mental disorders. In Chapter 2, I use wrist-worn acceleration data to detect hypoglycemia in individuals with type 1 diabetes. In Chapter 3, I examine the potential of acceleration data to detect stress in college students. In Chapters 4 and 5, I further extend my findings to stress detection using deep learning models, such as convolutional neural networks (CNNs) and Long Short-Term Memory (LSTM), in two populations: PTSD patients and Intensive Care Unit (ICU) nurses.
My first research (Chapter 2) shows the potential of wearable accelerometers in detecting hand tremors associated with hypoglycemia in diabetic patients. The ensemble of random forest, support vector machines, and K-nearest neighbor models achieved a precision of 81.5% and a recall of 78.6% for hypoglycemia detection. Furthermore, the proposed models for stress detection in college students (Chapter 3) achieved an accuracy of 72.45% for the general population and 78.11% for students with similar movement behaviors. In the PTSD study (Chapter 4), adding power spectral density to raw acceleration data significantly improved the accuracy of hyperarousal detection to 78.45%. Finally, the stress detection models in ICU nurses (Chapter 5) achieved an accuracy of 68.91% using a hybrid CNN-LSTM model.
In conclusion, this Ph.D. research shows the potential of wearable accelerometer data in detecting and monitoring chronic diseases and mental health disorders. The methodologies proposed in this dissertation can be deployed on wearable devices like smartwatches and provide interventions for managing chronic diseases and mental disorders
Unraveling the Complexity of Cdec Expression During Clostridioides difficile Sporulation: Insights into the Role of Sigma Factors and Non-Coding RNA on Cdec Expression
No full textGram-positive, obligatory anaerobic Clostridioides difficile (C. difficile) is a spore-forming, obligate anaerobic bacterium that causes diarrhea and other healthcare-associated illnesses globally. This study aimed to identify the sigma factor boxes in the promoter region of cdeC that affect the early and late stages of C. difficile sporulation. Therefore, we first identified the sigma factors' positions in the promoter region. Then, we constructed transcriptional fusions containing a different deletion of these sigma factors and introduced them into the C. difficile R20291CM210 WT strain. However, no detectable fluorescence was observed due to lack of sporulation in the C. difficile R20291CM210. Both increasing the time of incubation and increasing thiamphenicol concentrations failed to induce sporulation for R20291CM210. After that, we introduced all transcriptional fusions into the C. difficile R20291CM196 WT strain. We found out that only P���ncRNA-cdeC-mScarlett transcriptional fusion that contains the promoter region with a deletion of the ncRNA shows a modest fluorescence signal compared to other fusions. These results suggest that ncRNA located in the promoter region of cdeC may have an activity for cdeC expression during sporulation
Investigating Fifth Grade Teachers��� Implementation of ESL Instructional Strategies in Literacy-Infused Science Instruction
No full textThe purpose of this study was to investigate whether there is a significant difference in the time allocation of ESL instructional strategies between the treatment teachers who received literacy-infused science (LIS) curriculum accompanied virtual professional development (VPD) on such strategies as an intervention and control group of teachers who did not receive the VPD intervention. I further explored teachers��� perceptions of the impact and challenges of English as a Second Language (ESL) instructional strategy implementation in their science teaching practices and their students��� responses to the strategies.
To examine the differences in fifth-grade science teachers��� time allocation in their use of ESL instructional strategies between treatment and control groups, a low-inference observational instrument, Pedagogical Observation Protocol (POP), was used. Treatment teachers received bi-weekly VPD sessions provided through Project LISTO (Literacy-Infused Science Using Technology Innovation Opportunity, Grant Award No. U411B16001; Lara-Alecio et al., 2013), including a series of scaffolding strategies that benefit teachers��� professional growth as well as their students��� learning outcomes. A total of 14,332 rounds of observation clips were collected from 98 in-service science teachers who were randomly assigned to treatment and control conditions across Texas during the 2018-2019 academic year. Results revealed a statistically significant difference in 7 out of 9 strategies between treatment and control group teachers in utilizing ESL instructional strategies in science classrooms. Treatment teachers significantly used more strategies learned in VPDs than the control group of teachers. To further explore the perceived impact of ESL instructional strategy implementation, semi-structured focus group interviews were conducted for treatment teachers at the end of the school year. The results of the thematic analysis indicated a positive perception of using ESL strategies in science classrooms in terms of enhancing teachers��� quality of instruction and self-confidence as well as students��� science learning interest and literacy development. Therefore, this evidence supported that teachers��� instructional practice and student support were positively impacted by allocating a variety of instructional time toward ESL strategies. However, teachers encountered the challenges such as time constraints and technological issues while implementing ESL strategies might potentially lead to less time allocation in certain strategies
Effects of Information on Markets and Behavioral Economics
No full textThe dissertation systematically analyzed the effect of information in various aspects of economic and social systems. Specifically, it focused on tax information on food markets, market information on strategic decisions, and social information on decision-making in economic games.
The first essay investigated the effects of sugar-sweetened beverages (SSBs) tax in the city of Berkeley and Philadelphia. We constructed a difference-in-difference (DID) model to examine the effects of the tax on the consumption and retail prices using Nielsen retail scanner data. The finding suggested that SSBs tax had no significant effect on consumption and prices in Berkeley, while the tax significantly increased the price and decreased the consumption of SSBs in Philadelphia. The opposite results in the city of Berkeley and Philadelphia suggested that geographical and social demographic characteristics would affect the effectiveness of a policy, and SSBs tax works better in large territories with diverse population.
The second essay analyzed transaction data from eBay to explore sellers��� strategies in online auctions. We focused on three selling formats on eBay: fixed-price listings, auctions, and BIN(Buy it Now)-auctions, comparing new products and outdated products for electronics. A probit model and Heckman correction procedure were applied to examine the effect of seller���s selling strategy on transaction success rate, final transaction price, and the seller���s revenue. Results indicate that fixed-price listings are preferred. Selling formats significantly influence outcomes for new products, while they show minimal effects for outdated ones. Moreover, we identify key price determinants for each listing format. The BIN price is crucial for fixed-price listings. For auctions and BIN-auctions, the duration and starting price emerge as key factors influencing transaction outcomes.
The third essay explores cooperation in social dilemmas, focusing on the impact of inequality on cooperation in public goods dilemmas. Our study evaluate cooperation in metrics of efficiency (total contribution) and equality (contribution from the wealthy). Incorporating 32 articles with 50 experiments, we found that heterogeneous endowments do not significantly affect equality, but it negatively impact efficiency, leading to decreased total contributions. Overall, heterogeneous endowments detrimentally affect cooperation. Furthermore, moderator analyses show that iteration numbers could negatively moderate the relationship between heterogeneous endowments and cooperation, indicating a greater detrimental effect on cooperation in public goods games with more iterations
Musculoskeletal Pain and Preferred Pain Management Strategies Among Dental Professionals and Dental Students
No full textDental professionals and students are predisposed to musculoskeletal pain. However, few primary research studies have investigated musculoskeletal pain and pain management strategies among US-based dental professionals and students. Examining musculoskeletal pain and pain management experiences among dental professionals and students may provide inform opportunities to prevent musculoskeletal pain, thus improving their performance and retention in the workforce.
The primary purposes of this dissertation study were to: (1) understand issues that predispose dental professionals (workers and students) to musculoskeletal pain; (2) explain the associations between musculoskeletal pain and the strategies used for pain management; and (3) identify potentially harmful postures that could cause musculoskeletal pain among dental professionals by performing a concordance analysis of traditional ergonomic evaluation versus computer-based motion capture system assessment of select dental procedures.
The first study, a scoping review that examined musculoskeletal pain and pain management experiences of dental professionals and students, found musculoskeletal pain prevalence between 46% and 92.2%. The neck, wrist/hands, shoulders, and back had the most self-reported pain, while complementary alternative medicine (CAM) was the commonly used pain management strategy.
The second study administered internet-based surveys to dental professionals and dental students. Of the 1,510 study participants, 68.2% self-reported musculoskeletal pain. About 79.2% dental students, 70.6% dental assistants and hygienists, 65.7% dentists, and 60.4% dental therapists reported musculoskeletal pain. CAM (61.3%) and medication (49.7%) were the commonly used pain management strategies.
The third study, a concordance analysis of traditional (Rapid Entire Body Assessment, Rapid Upper Limb Assessment, and Strain Index) and computer-based ergonomic assessment (Humantech motion capture system) on non-participatory observation data, assessed the risk of developing musculoskeletal disorders among dental hygienists. Findings showed slight-to-fair agreement between traditional and computer-based ergonomic assessments. Findings suggest further refinement and testing of digital ergonomic assessment technologies are needed for the dental professions.
Taken together, this dissertation highlights the magnitude of musculoskeletal pain among dental professionals and students in the US and their preferences in strategies to manage pain. It illuminates factors associated with pain, the need for ergonomic assessment, and the potential for digital ergonomic assessment to detect harmful positions, which may cause or exacerbate musculoskeletal pain
A Climate Smart Agricultural Productivity Assessment of Smallholder Women Farmers in Farming Associations in Nigeria: A Mixed Methods Study
No full textThe world is plagued with multiple planetary threats of rising food insecurity, COVID-19 pandemic, aggravated conflicts, shrinking natural resources and worsening climate crisis. Smallholder women farmers (SWFs) fare even worse in Africa than their male counterparts due to limiting opportunity structures stemming from gender biases and discriminating societal norms. This mixed methods research assessed the interaction of climate smart agricultural practices (CSAPs) and agricultural productivity among SWFs in Nigeria using the climate smart sustainable livelihoods framework.
My findings provide evidence on the levels of use of CSA among SWFs and their agricultural productivity demonstrated by their state of empowerment. The study employed a convergent mixed-method design, collecting data from SWFs through structured interviews (n=196) and focus group discussions (six groups), which informed the quantitative and qualitative strands of the study respectively. Participants were mutually exclusive of the two strands of study. Data was analyzed using descriptive and inferential statistics, rich thick description, thematic analysis, patterns, themes, and representative quotes. Findings from the quantitative strand converged with the qualitative strand in a joint display of data.
The study revealed the most preferred CSAP used by SWFs is mixed cropping while the least used in crop insurance. Participants livelihood dynamics were described, and significant associations are observed between Educational Level and Use of CSA, as well as between Empowerment Level and Use of CSA. Additionally, a significant amount of variance was explained in the Empowerment Level based on the Use of CSA and Educational Level (R�� = 0.288, F = 39.00, p = <.001). Furthermore, six overarching themes emerged from farmers livelihood context, dynamics, and outcomes. The themes reinforced the existential threat of climate change and vulnerability of SWFs which is exacerbated by a complex interplay of factors.
The results were triangulated with the sustainable livelihoods framework which used Amartya Sen���s capabilities theory on the robust concept of agricultural productivity, not only in terms of yield or income but in the real doings and capabilities of what a farmer is able to do and has done with their capabilities. I found that although participants demonstrated adequate intrinsic, instrumental, and collective agency, they face obstacles such as poor infrastructure, unfulfilled government promises, and limited access to assets and tools which underscores systemic and institutional challenges that counterproductively affect agricultural productivity and empowerment.
Overall, I found SWFs are moderate and high users of CSA, but their livelihood outcomes are exacerbated by the negative effects of climate change and institutional failures. This underscores the need for targeted interventions, including improved infrastructure, access to resources, and supportive policies to enhance the resilience and empowerment of these farmers in the face of ongoing challenges
Thalamic Modulation of Hippocampal Context Memories During Conditioned Fear Learning
No full textMaladaptive fear poses a significant public health burden, particularly in the forms of anxiety and stress-related disorders such as posttraumatic stress disorder (PTSD), anxiety disorders, and phobias. A popular treatment for these disorders is exposure therapy, which utilizes the 'extinction' of fear through repeated, unreinforced presentation of a stressful cue. However, while effective, these therapies are still susceptible to relapse, in part because extinction memories are highly context dependent. Understanding the neural mechanisms underlying the contextual control of fear suppression becomes particularly important. Recent work has implicated the thalamic nucleus reuniens (RE) in extinction by allowing for bidirectional communication between the prefrontal cortex (PFC), involved in higher-order cognition, and the hippocamps (HPC), which encodes context information. This dissertation examines the specific role of the RE in modulating HPC context information. I first show that the RE is not involved in the storage of extinction memories, and then show that context representations in the HPC can be used to determine appropriate responding to fearful cues. Finally, utilizing selective interference of context memory formation, I illustrate that the RE relies on HPC context memories in order to exert control over contextual processes. Collectively, these data reveal a role of the RE in the suppression of context-inappropriate behavior and, therefore, in encouraging context-appropriate responses to ambiguous cues