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A Case Study Exploration of School-Based Mindfulness Instruction Through the Voices of Middle School Students with Emotional and Behavioral Disabilities
No full textThe incorporation of mindfulness-based interventions and programs within the education field is a recent and developing context. As the research on explicit school-based mindfulness instruction is emerging, there is a noticeable gap in the literature concerning the effect of this type of intervention for students with emotional and behavioral disabilities. The objective of this qualitative case study was to describe the experience of participating in a six-week school-based mindfulness program from the perspective of five middle school students who have been identified with an emotional disturbance. The effects of the intervention on the students' internalizing and externalizing behaviors were explored through the analysis of the students' and classroom teacher's post-instruction interview responses, the students' mindfulness journals, and school-based behavioral data. Research revealed that the present-moment awareness derived from engaging in mindfulness practices gave students space to think as opposed to responding impulsively, improved emotional regulation, and enhanced self-care and self-esteem. The externalizing benefits were a sense of calmness, an increased ability to respond with cognitive awareness to emotionally charged situations, and decreased incidents of verbal and physical aggression. Summarily, this study presents evidence that the students experienced internalizing and externalizing benefits from participating in the school-based mindfulness instruction program.Ed.D., Educational Leadership and Management -- Drexel University, 201
Eudaimonic Appreciation in Interactive Narrative
No full textThis thesis seeks to establish an approach to integrate thematic cohesion in interactive narrative. Psychological AI entities have been a promising possibility for interactive narrative because they can simulate characters that react appropriately to any situation. But even though they can act like human beings, this does not necessarily make them into good actors for an interesting dramatic story. In order for this to happen, the AIs need to be directed in some way, and various other designers have built such constraints directly into their patterns. However, my approach uses a separate narrative module to affect characters in a more subliminal manner, tilting characters towards a central theme while still giving them psychological agency.M.S., Digital Media -- Drexel University, 201
Life Cycle Environmental and Economic Evaluation of Pyrolysis Oil Upgrade Technologies
No full textGreenhouse gases are the leading contributors of climate change. The global rise of CO2 over the years, has urged an interest in government and researchers to find means of CO2 mitigation. Research has found that advanced biofuels can reduce CO2 emissions by up to 90%. Advanced biofuels can be produced from various routes, such as pyrolysis, gasification and torrefaction - with each route having limitations that hinder commercialization. A major limitation of pyrolysis-based advanced fuels also known as pyrolysis fuels, is their excessive cost of production due to their oxygenated structure; hence, their inability to be an infrastructure compatible market-ready fuel. In order to overcome this limitation, there is the need to deoxygenate the pyrolysis fuel. This thesis evaluates the environmental and economic sustainability of alternative pyrolysis oil upgrade technologies using life cycle assessment (LCA) and techno-economic analysis (TEA). The objective of this thesis is realized by completing three tasks: (1) examining the environmental and cost tradeoffs of the isolation and extraction of value added chemicals from tail gas reactive pyrolysis oil upgrade in comparison to the conventional hydrodeoxygenation upgrade (2) evaluating the implications of configuration, scale and hydrogen supply in alternative pyrolysis upgrade systems using life cycle assessment and (3) evaluating environmental, economic and technological aspects of alternative pyrolysis oil upgrading strategies Herein, we evaluate two emerging pyrolysis oil upgrade technologies; isolation and distillation of tail gas reactive pyrolysis (TGRP) oil and electrochemical deoxygenation (EDOx), and compare them to widely cited alternative technologies such as hydrodeoxygenation (HDO) and catalytic fast pyrolysis. We capitalize on some of the benefits of these emerging technologies; such as, the value-added coproducts in the TGRP process as well as the oxygen coproduced and the limited use of hydrogen in the EDOx process. Another main factor that sets these emerging technologies apart from the existing technologies is the smaller scale of 200MTPD in the TGRP process and 300 MTPD in the EDOx process compared to the larger scale (2000 MTPD) of the HDO process. In this thesis, we treat these co-products using system expansion in LCA and weigh in their value in the overall economics through measures like minimum fuel selling price (MFSP). The life cycle GHG emissions from the TGRP and EDOx processes, indicate reductions of 88% to 95% of emissions from petroleum-based fuels compared to 53% to 75% GHG reduction from the HDO processes and 89% to 90% from the catalytic pyrolysis processes. Also, The TEA results reveal that, even though the emerging technologies have a high minimum fuel selling price (MFSP) of 0.54 L-1 to 0.65 L-1, a price that is close to being economically competitive to petroleum- based fuels (0.48 L-1).Ph.D., Environmental Engineering -- Drexel University, 201
Novel calcium dependent mechanisms of NF-kappaB activation regulate lymphocyte tolerance and immunity
No full textThe central role of calcium signaling in the development of functional immunity and tolerance is well established. These signals are initiated by antigen binding to cognate receptors on lymphocytes that trigger store operated calcium entry (SOCE). The underlying mechanism of SOCE in lymphocytes involves TCR and BCR mediated activation of Stromal Interaction Molecule 1 and 2 (STIM1/2) molecules embedded in the ER membrane leading to their activation of Orai channels in the plasma membrane. STIM/Orai dependent calcium signals guide key antigen induced lymphocyte development and function principally through direct regulation of calcium dependent transcription factors. The role of calcium signaling in NFAT activation and signaling is well known and has been studied extensively, but a wide appreciation and mechanistic understanding of how calcium signals also shape the activation and specificity of NF-kappaB dependent gene expression has lagged. Here we discuss and interpret what is known about calcium dependent mechanisms of NF-kappaB activation and extend these findings through a series of detailed experiments in T and B lymphocytes. We find that calcium plays a central role in NF-kappaB signaling in both human and mouse lymphocytes through regulation of the activation of the IKK complex, through post translational modification of NF-kappaB proteins, and through regulation of de novo NF-kappaB protein expression. We find that calcium signaling plays a central role in NF-kappaB dependent cell fates including lymphocyte survival, proliferation, and differentiation indicating that these mechanisms play a central role in the development of functional immunity and tolerance. We also define new mechanisms by which antigen receptor induced calcium signals regulate other key signaling pathways in lymphocytes including mTORC1 and shed light on the implications of these findings.Ph.D., Biomedical Engineering -- Drexel University, 201
Effects of Misalignment of Total Ankle Replacement on Ankle Mechanics through Dynamic Simulation Approach
No full textMisalignment was identified as a cause for failure of total ankle replacement (TAR) [1,2]. The presumed mechanism leading to this failure is altered mechanical properties leading to elevated and concentrated contact pressure [1] and increased in micro-motion [2]. In this study we use image-based, three-dimensional (3D) musculoskeletal models to identify the changes in ankle mechanics due to TAR misalignment. Previously developed and validated 3D musculoskeletal models of the ankle complex were used to identify the effect of TAR misalignment on joint mechanics. A generic TAR with cylindrical articular surfaces replaced the natural surfaces of the ankles. The tibial and talar components were first inserted in an optimal fashion with the surfaces parallel to each other. A misalignment was then produced by translating (2 mm Elevation/Depression, 3 mm Anterior/Posterior) and rotating (10º Dorsi/Plantar Flexion, 10º Inversion/Eversion, 10º Internal/External Rotation) the tibial component. Simulations, conducted in ADAMSTM consisted of loading the model in all three planes while recording the applied loads, the displacements produced and the forces in the ligaments. From these results the following parameters were derived: surface-to-surface distance maps at the ankle, Range of Motion (ROM), stiffness, ligament forces, ligament strains, and kinematic couplings. Misalignment of the tibial component of TAR produces changes in the stiffness of the ankle joint complex, changes in the surface to surface interaction at the ankle joint and affects the forces and strains developed in the surrounding ligaments. Knowledge of the effect of misalignment of TAR is clinically relevant since it indicates the sensitivity of the mechanical behavior of the joint to component misalignment [3]. As such, this technique can be used as a predictive tool to indicate the most sensitive direction in which misalignment is critical.M.S., Mechanical Engineering and Mechanics -- Drexel University, 201
Synthesis and Electrochemical Characterization of Layered Oxides for Aqueous Energy Storage
No full textEnergy storage devices are quickly becoming a major requirement for human society, especially with the advancement of renewable energy and the rise of electric cars. However, current energy storage technologies can be dangerous, environmentally unfriendly, and expensive. Li-ion batteries, the most common rechargeable energy storage devices used commercially, utilize flammable electrolytes and in some cases toxic electrode materials. In order to overcome these drawbacks, new rechargeable energy storage devices are being investigated. One such technology that can address many of these issues is an aqueous-based energy storage device. These energy storage systems use water as the electrolyte solvent rather than expensive, environmentally hazardous, and flammable organic compounds. Aqueous energy storage devices tend to exhibit pseudocapacitance, and because of this, are often called "pseudocapacitors." Pseudocapacitance is a form of energy storage behavior that may exhibit both surface or near-surface reactions as well as some form of intercalation mechanism. Unlike typical battery intercalation reactions, pseudocapacitive storage is not limited by the diffusion of intercalating species. The focus of this thesis research is on the effect of structure and composition of layered transition metal oxide electrodes on their intercalation-based pseudocapacitive properties in aqueous systems Chemically preintercalated vanadium oxide (δ-MxV2O5, M = Li, Na, K, Mg, and Ca), which has been previously studied in non-aqueous Li-, Na-, and K-ion batteries, was investigated for its aqueous pseudocapacitive capabilities. First, the effect of post synthesis treatments on the initial capacitance and capacitance retention of δ-NaxV2O5 samples was investigated in order to identify the treatment combination leading to the highest performance. It was found that δ-NaxV2O5 samples that were aged and hydrothermally treated demonstrated the highest initial capacitance values of 230 F/g while samples that were aged and vacuum annealed exhibited the best capacitance retentions (68% after 50 cycles). The aged and hydrothermally treated and the aged and annealed post-synthesis treatment combinations were used on all five preintercalated δ-MxV2O5, materials (M = Li, Na, K, Mg, and Ca) and the effect of preintercalated ion on pseudocapacitive performance was studied. For all five phases, and a pH study was conducted to investigate the relationship between electrolyte pH and vanadium oxide stability in aqueous electrolyte. It was found that by lowering the pH from 6.67 to 2.35, an increase in capacitance retention of up to 35% and an increase in initial capacitance of 39 F/g could be achieved. The best initial capacity of 214 F/g observed was for aged and annealed δ-CaxV2O5 at a pH of 2.35. The highest capacity retention observed was 96.1 % for aged and hydrothermally treated of δ-LixV2O5 ¬at a pH of 2.35. The second part of this master's research was focused on the adaptation of the chemical preintercalation method developed in the Materials Science and Engineering group at Drexel for the fabrication of new layered transition metal oxides beyond vanadium oxide. For the first time, a novel family of layered tungsten oxides (MxWO3·nH2O, M= Na, K, Mg, and Ca) was synthesized. Na0.2WO3·0.8H2O phase demonstrated an initial capacitance of 60 F/g in an aqueous-based 1M H2SO4 electrolyte. Also, a pressure induced color change phenomenon was observed.M.S., Materials Science and Engineering -- Drexel University, 201
Evaluation of COPD Patient Education Methods: A Critical Appraisal and Product Evaluation Project
No full textAbstract Chronic Obstructive Pulmonary Disease (COPD) affects close to 16 million Americans and is the third leading cause of death in the United States with recent estimates of care costing approximately $49.9 billion. The 30-day hospital readmission rates for this diagnosis are exceedingly high with an estimate of 14%, thus making it imperative that patients have a solid understanding of their disease state. Continuous efforts are being made to improve patient care with the focus on patient education. Educational methods and tools utilized include paper brochures, verbal instruction, and use of Audiovisual tools including the Getwellnetwork(TM). At project inception, no process or protocol existed at the clinical site of interest to ensure that the content of educational materials are consistent with evidence-based and guideline recommendations. Additionally, educational content may not be reviewed to be actionable and understandable to the patients. Thus, revealing no standard method deemed superior to provide patients and caregivers education upon hospital discharge for a diagnosis of this chronic condition. A product evaluation and appraisal of an audiovisual educational platform known as the Getwellnetwork(TM) that is available on demand with the use of a SMART TV was completed. The appraisal was inclusive of a pulmonary interprofessional expert panel to ensure the modules and materials are reviewed from different healthcare disciplines. Panel members utilized the Patient Education Materials Assessment Tool for Audiovisual (PEMAT-AV) materials to assess module content for actionability and understandability. Results from this product evaluation project may be useful for other chronic disease education materials. Keywords: Chronic Obstructive Pulmonary Disease, COPD, Getwellnetwork (TM), PEMAT-AV, patient education, self-management, AV educationD.N.P., Nursing Practice -- Drexel University, 201
Is Fused Filament Fabrication a Viable Fabrication Method for Bioabsorbable Devices? Development of a 3D Printed Clip for Prevention of Spinal Fusion Infection
No full textLower back pain impacts a majority of the world population at least once in their lifetime. The source of this pain is often due to degenerative changes in the lower spine, sometimes requiring surgical intervention in the form of lumbar spinal fusion. Surgical site infection (SSI) is a serious complication of spinal surgery, affecting as high as 8.5% of the patient population. If the SSI cannot be eradicated with intravenous antibiotic therapy, the next step is a second surgery, involving debridement of the wound and replacing the infected device. Additional surgery not only increases the cost imposed on the patient but also extends recovery time.
In this study, an ultrasound triggered device for the dispersal of antibiotics, was developed as a potential solution. The device is constructed of a bioabsorbable polymer via fused filament fabrication (FFF). This device attaches to a standard 5.5 mm fusion rod and will degrade in vivo. Initially, a literature review was performed to determine the most appropriate polymer for this device. Poly-L-co-D,L-lactic acid (PLDLLA) 70/30 was chosen and a filament was fabricated. Gel permeation chromatography (GPC) and differential scanning calorimetry (DSC) analysis were performed to determine the molecular weight and thermal properties of the filament. The filaments were found to be consistent in molecular weight and thermal properties (p = 0.348 and p = 0.487, respectively). Once analyzed, the filament was then used for FFF printing. Initially, 1cm3 cubes were printed for optimization of printing parameters such as print speed and layer height. Then, printing of the spinal clip was attempted. Slight modifications were made to the clip design and printing parameters to reach the final product. Dimensional accuracy was assessed using µCT analysis. There was a difference between the thickness of the printed clip and the intended design (p = 0.029). All other dimensions were found to be similar. To assess the degradation, the clips were incubated at 37°C in PBS for a month and mass loss was measured at one-week time points. Additionally, raw pellets of PLDLLA 70/30 and the filament were degraded, and mass loss was assessed to evaluate how melting the material multiple times impacted the degradation properties. Degradation rate was found to be similar among the samples throughout the first three weeks of degradation however, the raw pellets were found to degrade at a slower rate by the final week (p = 0.039).
Further research should focus on additional print optimization as well as determination of the device coating method. Currently, the procedure for device coating involves dipping the device in PLA to create a thin film, but this has proven to result in a coating that is too thick to rupture with ultrasound. The next step would be to formulate a 3D printed coating option to optimize the coating thickness. This study demonstrated a promising future for this device and the viability of not only FFF with PLDLLA but other bioabsorbable polymers, increasing the reach of personalized medicine.M.S., Biomedical Engineering -- Drexel University, 201
Health Needs Assessment of the Theravada Buddhist Monastic Community in the Northeast USA
No full textThe Theravada Buddhist monastics community living in the northeastern United States of America is a vulnerable population that is not given much attention in the sphere of public health. This needs assessment sought to start laying the foundation for future research and projects to help this population. Information collected through this study has shown that there are some issues within the monastic community, such as a lack of knowledge regarding having regular wellness and care visits and lack of awareness of available community health care services. Additionally, the relationship between the monastic code of conduct and health outcomes was apparent. The results of this needs assessment and potential further areas of study on this population are discussed.M.P.H., Community Health and Prevention -- Drexel University, 201
Understanding the Role of Macrophage Phenotype in Biomaterial-Mediated Tissue Regeneration
Get PDFThe underlying goal of tissue engineering is to functionally repair and regenerate complex tissues and organs. One of the major challenges in engineering viable tissues is forming functional and stable blood vessel networks (angiogenesis) within the tissue, which supply oxygen and nutrients to the cells. Following implantation, these networks must subsequently connect with the body's existing vasculature (anastomosis) for continued survival. Currently, there is no known way to control anastomosis, preventing the translation of many potentially useful biomaterials for tissue engineering applications. Macrophages, the primary cells of the inflammatory response, are major contributors to vascularization and regulate the response to implanted biomaterials; however, macrophages are highly plastic cells that alter their behavior in response to local stimuli, and the contributions of macrophage phenotype to these processes are poorly understood. Therefore, the overarching goals of this work were to (1) understand how regenerative biomaterials modulate macrophage behavior and (2) delineate the impact of changing macrophage phenotype on biomaterial vascularization. First, the in vitro response of primary human macrophages to biomaterials proven to enhance tissue regeneration in animal models was evaluated. Interestingly, biomaterials more successful in promoting tissue repair induced a phenotypic shift in macrophage behavior toward an anti-inflammatory "M2" state. The modulatory effects of these scaffolds were predominantly due to direct cell-scaffold interactions, as only modest changes in macrophage gene expression were observed by soluble factors derived from the scaffolds. Importantly, these findings provide evidence that regenerative biomaterials modulate macrophage behavior. Then, to elucidate the effects of changing macrophage phenotype on biomaterial vascularization, crosstalk between macrophages and vascular endothelial cells (ECs) was assessed via transwell co-culture. Interestingly, the angiogenic behavior of ECs was differentially influenced by macrophage phenotype; specifically, macrophages stimulated toward M1 and M2c activation induced EC up-regulation of genes related to vessel sprouting, while M2a and M2f macrophages altered genes related to vessel branching and extracellular matrix disassembly, respectively. Finally, the functional consequences of changing macrophage phenotype on biomaterial vascularization were ascertained through development of a 3D in vitro model of vascular growth. Self-assembly of ECs and support cells into vascular structures was achieved by co-culture on commercially available Gelfoam(r) scaffolds, to which macrophages were seeded at different stages of vessel development. Consistent with the previous study, M1 and, to a lesser extent, M2, macrophages increased vessel sprouting and the number of connected vessels relative to vascular networks without macrophages. Preliminary studies also demonstrated the potential for temporal control over macrophage activation to enhance vascularization. Collectively, these findings can be used to inform the design of biomaterials that harness the inflammatory response to promote vascularization and improve healing outcomes. This work also has important implications for treating diseases characterized by extensive blood vessel growth, such as cancer and autoimmune conditions, whereby vascularization of the tissue facilitates disease progression.Ph.D., Biomedical Engineering -- Drexel University, 201