19304 research outputs found
Sort by
Targeting Neuroinflammation for Therapy of Vascular Dementia
No full textVascular dementia (VaD) arises from chronic cerebral hypoperfusion and microvascular pathology, leading to cognitive decline, neuroinflammation, and white matter degeneration. Despite its increasing prevalence, effective therapeutic strategies remain limited. This dissertation explores two key pathogenic mechanisms—NLRP3 inflammasome activation and Hippo pathway dysregulation—as central contributors to VaD pathology. Using the bilateral common carotid artery stenosis (BCAS) mouse model, we investigated the therapeutic potential of the novel NLRP3 inhibitor AMS-17. AMS-17 treatment significantly reduced microglial activation, mitigated neuroinflammatory cascades, preserved blood-brain barrier (BBB) integrity, and improved cognitive function in behavioral assays. In parallel, we identified aberrant activation of the Hippo signaling cascade in VaD, characterized by elevated MST1 phosphorylation and reduced YAP nuclear activity in both in-vivo and in-vitro models. Pharmacological inhibition of MST1 using XMU-MP-1 rescued neurocognitive deficits, suppressed neuronal apoptosis, and restored oligodendrocyte function in BCAS mice. Mechanistically, we uncovered a novel crosstalk between the NLRP3 inflammasome and Hippo pathway, where NLRP3 knockdown attenuated MST1 phosphorylation. In vitro studies using oxygen-glucose deprivation (OGD) in SH-SY5Y cells validated these findings. Collectively, this study identifies NLRP3 and MST1 as critical molecular hubs in VaD and demonstrates the therapeutic potential of their inhibition. These insights advance our understanding of neurovascular crosstalk and provide a mechanistic foundation for developing disease-modifying therapies for VaD
Implementing and Using Video Telemedicine as a Form of Innovation Amidst COVID-19: The New Normal
No full textBackground: Video telemedicine started in Pennsylvania in the 1940s but was first used in the 1950s by University of Nebraska’s health workers. NASA (National Aeronautics and Space Administration), the public health department, the department of defense, and the U.S. health and human services department put in money and time for its research in the 1960s and 70s. The partnership between Indian health services and NASA was one of the most successful government projects. Space technology applied to rural Papago advanced health care (STARPAHC) was the project’s name. Astronauts and Native Americans of the Papago reservation in Arizona had access to medical care thanks to the project. There have been barriers over the years in adapting to telemedicine and using tools for remote monitoring of patients’ health. Regulatory, financial, and technological challenges made it difficult to advance its adoption: not having the broadband infrastructure that required high demand videos with extensive networks was a challenge. Presently, clinicians can use telemedicine to detect patients’ conditions, communicate with patients and those providing bedside care, and implement treatment. Purpose: The purpose of this qualitative descriptive study was to examine the challenges CEOs (Chief Executive Officers), CMOs (Chief Medical Officers), and CNOs (Chief Nursing Officers) of hospitals in the Houston area face in implementing video telemedicine in an ICU (Intensive Care Unit) setting. The research question was: What implementation strategies do CEOs, CMOs, and CNOs of hospitals in the Houston area use to implement telemedicine in an ICU setting? By exploring and considering the challenges, this study helped determine which implementation strategies provide the most value in the successful implementation of video telemedicine. This research can serve as a guide map for healthcare leaders who plan on implementing video telemedicine from the data presented. Methods: The researcher used a qualitative descriptive design for this study. The participants were five C-suite executives (1CEO, 3CMOs, and 1CNO) from five different hospitals in the Houston area. The researcher recruited participants by making telephone calls, sending emails, and sending consent forms to those who agreed to participate in the interviews. Interview questions were about the challenges participants faced in implementing telemedicine in an ICU setting and if it was beneficial to patients’ quality of care and safety. All data were collected using individual and open-ended interviews in 12 weeks. They were analyzed using a coding system such as HW for handwritten notes, EM for interview answers gotten via emails, and VR for video-recorded interviews. Results: Findings from this study disclosed that implementing video telemedicine was useful to providers and patients. Participants faced challenges such as resistance to change, IT functionality, bandwidth, privacy rules, equipment, and costs in the implementation phase. Four participants successfully went through the implementation phase. One participant is still in the implementation process. Every participant interviewed mentioned a growing need for video telemedicine adoption with the COVID-19 surge. All participants noted that measures such as continuing education were put in place by leaders for sustainability. Also, having video telemedicine increased access to care, improved patient safety, and quality of care. Conclusion: This study has generated results that show an increasing need for video telemedicine in many ICU settings today. There are still adoption issues faced with broadband infrastructure, costs, and regulations. Providers are mindful of the need and curious about legislation in place to allow cross-state licensure. Lastly, each participant expressed the benefits of having video telemedicine, especially during COVID-19
The Theatre Pipe Organ: An Overview. Considerations of History & Performance Practice
No full textIn the 1920s, the American public enjoyed an explosion of exciting new entertainment experiences and was able to savor the creativity of many renowned artists and musicians who came from abroad to relish in the promise of new opportunities. Toward the end of the decade, their appetite had reached extraordinary heights. A steady stream of vaudeville shows and silent films, later replaced by “talkies,” ensured that the notion of attending the theatre became a practically ritualistic way of life. One of the most cherished places of entertainment was the “movie palace.” These magnificently ornate structures provided the ultimate escape into a fantasy world of illusion and wonder for the patron. Among the most crucial components of any successful movie palace was an instrument that enhanced the movie-going experience with a tremendous grandeur—the Theatre Pipe Organ. The theatre organ is an instrument whose origins exist within the realms of traditional church organ building, a field of musical and technological development itself spanning hundreds of years, but one which was aligned with the changing demands and styles of music seen throughout the 1920s. It was an invention borne out of necessity, change and innovation. Its creation, a product of the fertile mind of inventor and engineer Robert Hope-Jones, marked an important turning point in the history of organ building and represents one of the most radical reconsiderations of what a pipe organ could be. American organ building trends had, by this time, moved towards a more orchestral ideal and the theatre organ was an integral part of this, the tonal philosophy being that it should resemble the orchestra as closely as possible. This concept proved invaluable to theatre operators during the 1920s when they were searching for a means of providing maximally varied music at minimal cost. The primary concern of this thesis is the history of the theatre organ, its use and repertoire, and the necessary question of how one can learn to play based on historical recordings, treatises on arranging, and more contemporary performance practices since comparatively little has been written on the subject
Reconstructing the Late Pleistocene-Early Holocene Paleoclimate Using a Stalagmite from Rodrigues, Southwest Indian Ocean
No full textRodrigues is a small volcanic island, located ~600 km east of Madagascar in the Southwest Indian Ocean (SWIO). This region bears a unique climate due to its sensitivity to the zonal shifts in the Inter Tropical Convergence Zone (ITCZ), offering an ideal setting for paleoclimatic research in the Southern Hemisphere (SH). Here, we used a stalagmite named LV01A, a secondary cave deposit, from La Vierge Cave to derive paleoclimate records from Rodrigues Island. The study period ranges from 13.9 ky B.P to 10.3 ky B.P, an interval spanning the Pleistocene-Holocene transition. Using stable isotope proxies (δ¹³C and δ¹⁸O) that are constrained using the 234U/230Th method, we investigated the hydroclimatic variations over the Rodrigues Island. Age model reveals a noticeable hiatus in the stalagmite, lasting about ~2 ky, and was constrained between 13.4 ky B.P and 10.8 ky B.P. This timing corresponds to the Younger Dryas (YD), an abrupt cooling period identified in ice core records from the Northern Hemisphere (NH), that lasted ~1300 years. Following this hiatus, a fast growth rate was noted between 10.8 ky B.P and 10.3 ky B.P. Analyses of both δ¹³C and δ¹⁸O values suggest abrupt fluctuation from a warm/wet to cold/dry climate before the hiatus. The isotopic values following the hiatus suggest a gradual recovery in precipitation and vegetation patterns. While comparing the LV01 stable isotope data with paleoclimate records from East Africa, and with NGRIP and TALDICE ice core records from Greenland and Antarctica, respectively, the data seem to suggest an arid SH during a colder NH. High resolution dataset is still needed to understand the late Pleistocene-early Holocene transition in SWIO
The Difference in English Learner STAAR Scores of Special Education Students and Tier III Students
No full textBackground: The number of students identified as special education and English Learners (ELs) has increased by over 1 million in Texas. Research demonstrates that the earlier the intervention and support are given to ELs, the more likely they will see a reduction of literacy struggles throughout their educational journey. Purpose: This study aims to investigate the differences between MTSS Tier III support and special education services for English Learners (EL) in an elementary school and how the early intervention supports the students in their reading level. This study seeks to answer three questions: 1) What is the distribution of support services (MTSS, SPED, LPAC) by student classification (EL v. non-EL)? 2) What difference, if any, exists for students classified as EL in the performance on the STAAR Reading measure based on support services provided (MTSS, SPED, LPAC)? 3) To what extent are the district Tier II and Tier III research-based interventions aligned with the What Works Clearinghouse (WWC) evidence standards? Method: This quantitative study will focus on all EL students in grades three through five in a suburban school district in Southeastern Texas. This study will utilize publicly available archival data for the students collected over four years from 2021-2023. A t-test will determine if there are statistically different means of the reading score between the three support services offered to EL students. In addition, the district’s Tier II and Tier III interventions will be reviewed using evidence standards presented by the Department of Education’s What Works Clearinghouse. Results: The study found that EL students received more MTSS and SPED services than non-ELs, with LPAC services exclusive to ELs. MTSS students had higher STAAR reading scores than those in SPED, while LPAC students showed intermediate performance. Tier II and III interventions were partially aligned with WWC standards, some interventions met evidence-based criteria, while others required improvement. Conclusion: This study highlighted the importance of early interventions for ELs, showing MTSS services yield better reading outcomes than SPED. While some district interventions align with research-based standards, others need refinement. Improving alignment with effective practices could enhance literacy outcomes for EL students
Scalable Synthesis and Separation Performance of Covalent Organic Framework and Contorted Polyamide Membranes
No full textSeparation processes are imperative to industries including chemical manufacturing, resource recovery and product purification. Conventional separation processes like distillation and solvent extraction are energy and chemical intensive with large environmental footprints. Membrane separation processes are an environmentally friendly alternative to conventional processes due to their higher energy efficiency and precise separation capability. Nanofiltration (NF) is used to separate relatively small molecules like pharmaceuticals and colorants using nanoporous membranes. Reverse osmosis (RO) separates smaller constituents like ions and sugars from solvents using non-porous dense polymeric membranes. Both NF and RO membranes are commonly thin film composites (TFC) made via interfacial polymerization. Covalent organic framework (COF) based TFC membranes are a new class of membrane materials ideal for NF applications, and specifically organic solvent nanofiltration (OSN), because of their crystalline, highly porous structures and chemical and thermal stability. Contorted polyamide TFC membranes are also a new class of polymeric membranes suitable for enhanced RO water desalination due to their increased free volume resulting from sterically hindered monomer structures. COF and contorted polyamide membranes show great promise for achieving superior permeability and selectivity compared to commercially available counterparts, but their industrial scale application is hindered by small scale synthesis approaches. Moreover, transport in these membranes is not well understood beyond the conventional pore-flow and solution-diffusion models, which limits their performance predictability in challenge separation processes. To address these critical research gaps, this dissertation investigates the OSN performance of COF membranes by correlating the physicochemical properties of membrane to that of organic solvents based on membrane-solvent interactions. Second, a novel scalable approach for synthesis of COF membranes at large scale is introduced, and the resulting COF membranes are shown to perform similarly to COF membranes made using conventional methods. Lastly, large scale synthesis of contorted polyamide membranes is demonstrated, and the physicochemical characteristics and desalination performance of these membranes are evaluated. Results of this work show superior permselectivity for contorted polyamide membranes compared to conventional polyamide membranes due to their increased free volume. A solution-friction model is applied to describe transport in these membranes and to explain changes in membrane free volume and desalination performance due to compaction
AI Approaches for Feature Extraction in Multimodal Biomedical Data
No full textArtificial intelligence (AI) has myriad applications for biomedical engineering and healthcare. In particular, with the diverse modalities and high resolution of physiological data, the potential for data-driven approaches to elucidate meaningful insights is enormous. However, the enormity and profundity of this data is also a hindrance. AI approaches can fail to learn due to "feature dilution", where a model is overloaded with data points, and spurious or noisy features prevent it from successfully aligning to and converging on semantic or predictive features in the dataset. Traditional methods of feature extraction either rely on manual physiological inference or leverage pre-trained AI models for well-characterized applications. We posit that AI itself can be leveraged to augment feature identification through the exploitation of learned representations and intelligent processes. To address this problem, we present three approaches for the application of artificial intelligence to the task of feature extraction in three different modes of biomedical data: 1. AxoDetect (AD), a complete image-to-model software pipeline for in silico nerve stimulation using computer vision (CV); 2. Probability Gradient Thresholding (PGT), a deep learning-based dynamic time window extraction method for the identification of neuronal compound action potential (CAP) spikes from neuronal recordings; and 3. Latent Semantic Atom Analysis (LSAA), a hybrid approach using Matching Pursuit (MP) and DeepSets (DS) to learn patient-specific representations of atherosclerosis in the coronary arteries from human heart sound data. AxoDetect excels at segmenting nerves without requiring labeled datasets, segmenting between ten to one hundred times faster than similar deep learning methods. The models which are functionalized and constructed by the software have statistically indistinguishable results when compared to the gold standard modeling methods (Wilcoxon followed by MWU with Bonferroni correction). A combined RNN-LSTM approach to PGT was able to achieve over 95% point-wise accuracy on the testing set in identifying a data point's belonging to a neuronal spike on in silico recordings. Finally, using LSAA we can not only predict presence or absence of cardiac stent with high accuracy (88% on the test set, 94\% on the full dataset), we can isolate and cluster semantic groups of atoms representing cardiac occlusion
A Quantitative Study on the Disproportionate Outcomes for Students in State Conservatorship Foster Care: A Study of Educator Influence and State Policy Implementation
No full textBackground: Students in foster care, (students-in-care) are 3.6 times more likely to drop out and have lower graduation rates. Educators’ awareness of foster care status and relevant policies can significantly impact these students’ educational outcomes. Purpose: This study examines how educators' decisions affect the educational outcomes of students-in-care. It addresses three questions: 1) What difference, if any, is there in disability identification for students-in-care and students without a foster care status by disability category? Are there differences in the educational environment for students-in-care with disabilities and students without a foster care status by disability category? 2) What difference, if any, is in high school graduation rates for students-in-care, students with and without disabilities, and students who fit both categories? And (3) to what extent are the federal, state, and local policies aligned to support students-in-care through their educational experiences? Method: The study uses quantitative descriptive statistics to analyze the variables influencing educational outcomes for students-in-care. Pearson’s Chi-Square and Cramer’s V analyses were applied to cross-sectional and longitudinal data from a Southeastern Texas school district. The research also examines how policies at various levels support the educational stability and outcomes of students-in-care. Findings: The study found that foster care status significantly impacts disability identification and categories, with students-in-care often identified with emotional disturbance and intellectual disabilities. Students-in-care with emotional disturbances and intellectual disabilities are frequently instructed outside the general education classroom for over 60% of the day. Disability identification and foster care status also significantly affect graduation rates. Document analysis showed federal regulations are largely reflected in Texas statues but limited in district policies. Conclusion: These findings align with existing research and emphasize the need for educators to consider foster care status when addressing disability identification, educational environments, and graduation outcomes. They also highlight the importance of educators being aware of regulatory practices
Improve Peripheral Nerve Regeneration Using Dual Growth Factor Delivery and Electrical Stimulation
No full textSignificant challenges remain in the treatment of peripheral nerve gap injuries. We previously reported successful axon regeneration across a 40 mm nerve gap using a biosynthetic nerve implant (BNI) with multi-luminal synergistic growth factor release. However, axon sorting, remyelination, and functional recovery were limited. Neuregulin1 (NRG1) plays a significant role in regulating the proliferation and differentiation of Schwann cells (SCs) during development and after injury. We hypothesize that the release of NRG1-III combined with pleiotrophin (PTN) in the BNI will enhance axon growth, remyelination, and function of regenerated nerves across a critical gap. In addition, electrical stimulation has been reported to promote peripheral nerve regeneration by accelerating axon growth. Hence, the purpose of this dissertation is to characterize the therapeutic effects of dual growth factor delivery and wireless electrical stimulation for peripheral nerve injury. We evaluated the effects of NRG1 and PTN on nerve regeneration in a 4 cm PNI gap repair, characterized the axon target innervation after sub-chronic nerve stimulation, and investigated the effects of chronic nerve stimulation on nerve microanatomy in animal disease models. By conducting behavioral study, electrophysiology, histology, immunofluorescence, and transmission electron microscopy, we found that pleiotrophin promoted axon regeneration and neuregulin1 promoted axon sorting in conduit repair of critical nerve gap injuries. In addition, we found sub-chronic BsN neuromodulation significantly increased the axon innervation and Piezo1 expression of the bladder tissue in mature multiparous rabbits. We also characterized the effects of chronic electrical stimulation on nerve microanatomy. Together, the research work presented in this dissertation provided valuable insights into the therapeutic effects of the above-mentioned therapies and the underlying cellular and molecular mechanisms. The results of this study will greatly facilitate the development of novel nerve regeneration therapies and the translation of these therapies into the clinic
Development and Analysis of Converter Architectures for Specialized Applications: Power Distribution for Underwater ROV Systems and Lunar Power Grids
No full textThe rapid advancement in power electronics has opened up new opportunities to develop practical solutions for specialized applications that were previously considered unfeasible. Key developments include the industrialization of wide-bandgap (WBG) devices and their integration into power converter structures, such as solid-state transformers (SSTs), which have revolutionized power distribution and conversion. This thesis investigates potentially viable solutions for two specialized applications: an underwater power system for remotely operated vehicles (ROVs) and a distribution system on the lunar surface. In the case of the ROV power system, an input-series-output-parallel (ISOP) modular architecture using interleaved SST modules with fault-tolerant capabilities is being presented and analyzed. To validate the analysis, real-time Hardware-in-the-Loop (HIL) simulations are conducted using a Typhoon HIL system, with the results demonstrating the effectiveness and reliability of the proposed solutions. In the pursuit of sustainable lunar power systems, a reliable DC power distribution architecture is proposed and examined. This work also compares viable AC and DC distribution systems to evaluate their performance under these environments. Simulation results are also included to demonstrate the variation in source power with varying conditions on the lunar surface