16484 research outputs found
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Power and Paddle Strokes in a Robotic Sea Lion Pectoral Flipper
No full textSea lions have the potential to serve as an excellent model for unmanned underwater vehicle (UUV) technologies which must operate in high energy flows are transition from underwater swimming to terrestrial locomotion. Though investigations have been conducted to predict the mechanisms by which the sea lion produces forces during swimming in the power and paddle phases of its stroke, few, if any, devices have been developed to recreate their clapping gait and capture force data and experimentally observe these mechanics. This study explores how forces are produced by a robotic foreflipper when driven over a series of strokes which modify key parameters of these power and paddle phases and how swimming performance can be altered based on these modifications. It was found that increasing speed in the power stroke increases thrust production in both the power and paddle phases of the stroke while also increasing lateral forces by varying degrees depending on the compliance of the flipper. Increasing power stroke angle was detrimental in both phases when the velocity of the paddle stroke was standardized in all experiments, but standard duration paddle strokes did demonstrate some increase in thrust production for slightly higher power stroke angles, especially in the case of the stiffer flipper. These results demonstrate how sensitive forces can be to these small modifications and what considerations must be made in order to properly take advantage of this swimming gait in an engineered system.M.S., Mechanical Engineering and Mechanics -- Drexel University, 201
Restitution and Cultural Heritage Policy within Museums: Administrative Recommendations for Collections Management Staff
No full textThe purpose of this study is to investigate the ways in which museum administrators and collections managers address and implement current restitution practices when dealing with issues of cultural heritage and repatriation. The objective of this thesis was developed in order to further research how various museums have trained their collections management staff to address issues of restitution and cultural heritage policy and how such practices affect the legal, curatorial, and general institutional approaches that museum take when met with such issues. Four museums of various size and specialty were selected based on their past and current involvement with addressing and implementing restitution practices. Interviews were conducted over the phone and in person with one or two staff members from each museum. The findings were comprised as comparative case studies for each institution. My core findings of research show that collections managers and other museum staff believe that there are numerous ways to go about addressing issues of restitution and cultural heritage. Similarities in this practice come from a commitment to thorough research on all objects within their respective collections, open communication with museum audiences, and internal collaboration. The results also reveal that the museum field still has to work on allocating financial and legal resources for all cultural institutions regardless of size so that all collections can be researched, displayed, and occasionally restituted at the same level as one another. I suggest that museums with the means and resources to conduct and implement current restitution practices to their full ability should strive to assist other institutions that do not have the proper resources and manpower needed to address such issues in a timely and legal matter so that all collections and cultural groups involved in restitution issues are able to work together to provide transparency and viable outcomes for all parties involved.M.S., Arts Administration -- Drexel University, 201
Applying traumatic body memory theory to a childhood context using a dance/movement therapy perspective
No full textThis work explores the literature on body memory and memory processing theory specific to traumatic experiences. It integrates ideas that are heavily rooted in development and attachment theories and applies them to models of memory encoding on a body level. By adding a lens that layers child development and attachment onto existing theories of body memory, this work provides a foundation from which traumatic body memory can be situated as a new theory in the childhood context. While this theory is not novel, it does reframe the literature to address this phenomenon in children. This work was highly informed by a dance/movement therapy perspective.M.A., Dance/Movement Therapy and Counseling -- Drexel University, 201
Bringing Connection through Movement for Latinos with Dementia: A Grant Proposal Project
No full textThere is an increased risk of being diagnosed with dementia with the increased life expectancy within the United States. While the growing Latino population in the United States, there is a need to provide culturally competent therapeutic services to those in need. The United Community Center has been serving the Latino population in Milwaukee, Wisconsin since 1970. As one of their services, they provide respite to caregivers of older adults with dementia through an adult day care. The purpose of this capstone project was to learn about the cultural influences and proposer methods for developing a dance/movement therapy program at the United Community Center: Adult Day Center. The literature review included the cultural trends in healthcare, caregiver education on dementia, different theoretical approaches and creative approaches to working in dementia care. The literature review helped formulate a need fore the population, develop methods and goals, and inform how to implement a new dance/movement therapy program. The aim of the program is to incorporate a psychosocial approach, educate caregivers on nonverbal communication, and help increase the sense of vitality in the lives of older adults with dementia. The grant proposal was tailored to fit the requirements for the Wisconsin Arts Board: Creative Communities grant.M.A., Dance/Movement Therapy and Counseling -- Drexel University, 201
sTNF[alpha] Signaling Mediates Autonomic Reflex Circuits Implicated in Cardiovascular and Immune Dysfunction After Spinal Cord Injury
No full textThe sympathetic nervous system is a critical regulator of cardiovascular and immune function. Sympathetic preganglionic neurons (SPN) reside in thoracolumbar cord and project peripherally to communicate information to vasculature and lymphoid organs. High-level spinal cord injury (SCI) can result in a loss of descending modulation of SPNs and lead to cardiovascular and immune dysfunction, which are two leading causes of mortality and morbidity after injury. Following SCI, SPNs become hyperactivated by autonomic reflexes in response to noxious stimuli below the level of the injury. Activation of these spinal sympathetic reflexes (SSR) can acutely manifest as autonomic dysreflexia (AD), a condition characterized by life-threatening hypertension in response to visceral or cutaneous stimuli. Recent work suggests that aberrant activity of this reflex can also suppress immune function. Furthermore, there are injury-induced changes to plasticity within the SSR circuits that further exacerbate sympathetic output and drive cardiovascular and immune dysfunction over time. Hyperexcitable circuits are a common sequela in other CNS disorders, including epilepsy and neuropathic pain. One commonality that may underlie these pathologies is an activated neuroimmune system. Interestingly, the pro-inflammatory, soluble form of the “master regulator” cytokine tumor necrosis factor [alpha] (sTNF[alpha]) has been shown to not only recruit immune cells to an injury site – sTNF[alpha] can also modulate neural circuits. Whether neuroinflammation instigates spinal plasticity related to the exacerbation of AD and dysimmunity has not been directly tested. We hypothesize that sustained sTNF[alpha]/TNFR1 signaling in the spinal cord below a SCI plays a crucial role in SSR circuit hyperactivity and consequent cardiovascular and immune dysfunction. In this thesis, we will assess whether pharmacologically inhibiting sTNF[alpha]/TNFR1 signaling attenuates these maladaptive changes. Results from chapter 2 demonstrate that immediate application of a sTNF[alpha] biologic, XPro1595, via continuous, intrathecal delivery below a thoracic segment 3 transection (T3Tx) can dramatically attenuate the development of naturally-occurring and induced AD as well as immunosuppression 4 weeks after SCI. Extracted mesenteric arteries from T3Tx-Saline animals exhibited increased sensitivity to vasopressors, suggestive of maladaptive vascular remodeling. Additionally, harvested spleens from T3Tx-Saline animals showed reduced levels of leukocytes suggestive of diminished immune function. Conversely, arteries from T3Tx-XPro1595 animals showed a normal pressor response and spleens from these animals also had normal leukocyte profiles Furthermore, XPro1595 animals show diminished intraspinal plasticity compared to T3Tx-Saline animals - far less activation of spinal interneurons in response following a colorectal stimulus, likely due to decreased arborization of colorectal nociceptive primary afferents. We believe that results from chapter 2 indicate that intrathecal XPro1595 may be a promising therapeutic strategy, so as a follow up study in chapter 3, we determined whether delaying initiation of XPro1595 at a more clinically relevant time point would sufficiently dampen SSRs, AD and improve dysimmunity. Indeed, delaying XPro1595 decreased recruitment of sympathetically-associated interneurons at both lumbar (where colorectal afferents synapse) and thoracic (locally to SPNs) levels compared to T3Tx-Saline animals. Likewise, T3Tx-XPro1595 animals had less naturally-occurring episodes of AD and diminished colorectal distension-induced AD over 8 weeks post-SCI. Interestingly, T3Tx-XPro1595 also fared much better than T3Tx-Saline animals following a bacterial infection 8 weeks after injury, suggestive of improved immunity. Collectively, the data presented in this thesis suggest that spinal inflammation may be a useful therapeutic target to curtail sympathetic reflexes implicated in secondary consequences of high-level SCI.Ph.D., Neuroscience -- Drexel University, 201
Role and mechanism of host cellular DNA repair proteins in hepatitis B virus cccDNA biosynthesis
No full textPersistent hepatitis B virus (HBV) infection relies on the establishment and maintenance of covalently closed circular (ccc) DNA, a 3.2-kb episome that serves as a viral transcription template, in the nucleus of an infected hepatocyte. Although evidence suggests that cccDNA is converted from its precursor molecule, relaxed circular (rc) DNA, by exploitation of host cellular DNA repair machineries, the host DNA polymerases involved in repairing the discontinuity in both strands of rcDNA remain to be fully understood. Taking a chemical genetics approach, DNA polymerase alpha (Pol [alpha]) was identified as a novel host factor essential for cccDNA biosynthesis from progeny rcDNA. Specifically, inhibition of Pol [alpha] by the small molecule inhibitors aphidicolin or CD437, as well as silencing of Pol [alpha] expression by small interfering (si)RNA, led to suppression of cccDNA formation in human hepatoma cells. Clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 knock-in of a CD437-resistant mutation into Pol [alpha] genes completely abolished the effect of CD437 on cccDNA formation, indicating that CD437 directly targets Pol [alpha] to disrupt cccDNA biosynthesis. Mechanistically, Pol [alpha] is recruited to HBV rcDNA and involved in the repair of the rcDNA minus-strand nick during cccDNA synthesis. Our study also identified a small molecule compound that enhances the conversion of rcDNA into cccDNA. The enhanced synthesis of cccDNA molecules requires the induction of cellular responses to assemble more productive DNA repair complexes onto rcDNA. Further investigation of the mechanism and molecular regulation of cccDNA biosynthesis should reveal molecular targets for developing therapeutic agents to eradicate cccDNA and cure chronic hepatitis B.Ph.D., Microbiology and Immunology -- Drexel University, 201
Visual Art Journaling as a Mindful Practice with Patients and Professional Caregivers in Oncology Care
No full textThis paper describes the development and implementations of a method that combines the use of a visual art journal as a mindful practice to combat the effects of cancer on patients diagnosed and professional care providers. The development of the method required adaptations specifically to group membership and the structure used. Implementation of this method explored ways of using mindfulness and Visual Art Journaling to uncover, document, and creatively express areas of wellness each week of a seven-session process. To do this, group members journaled with both words and images the areas of wellness in their lives and ways of improving their coping mechanisms while undergoing cancer treatment and/or caring for others in their lives. This capstone discussion aimed to highlight ways in which group members developed purposeful awareness of thoughts and emotions, and as they occurred in a non-judgmental way, through the utilization of mindfulness-based Visual Art Journaling explorations, to address stress and anxiety within oncology treatment and care.M.A., Art Therapy and Counseling -- Drexel University, 201
Development of lectins for cancer-specific fucosylation
No full textChanges in serum glycosylation have long been associated with hepatocellular carcinoma (HCC), and these modifications are often detected with sugar-binding proteins called lectins. HCC is associated with increased serum fucosylation, and this sugar is often detected with the Aleuria aurantia lectin (AAL). However, this lectin binds fucose in several forms, one of which is associated with cancer ([alpha]1-6 linked fucosylation) and some of which are not. Thus, its use in clinical and tissue analysis is limited. We have created a recombinant AAL, which contains a single amino acid mutation: N224Q (rAALN224Q), within the binding site 5, and this lectin has increased sensitivity to the cancer-specific fucosylated glycan. Our analysis of rAALN224Q has shown that the mutation within one specific fucose binding pocket had a major impact upon the mutated site as well as on sites that were not mutated and led to a lectin with altered binding specificities. This lectin is currently part of a diagnostic test under evaluation for the early detection of HCC. We have further explored the changes in N-linked glycosylation associated directly with HCC tissue through a method of N-linked glycan matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI IMS). MALDI IMS of N-linked glycan revealed inter- and intra-tumor heterogeneity shown by expression and spatial localization of glycans in the tumor. Tumors were associated with alterations in mannosylation, fucosylation, branching, and complex glycan formation. Importantly, all tumors were associated with some change in glycosylation, but there was significant glycan heterogeneity.Ph.D., Microbiology and Immunology -- Drexel University, 201
A Three-Step Method for Educators Working with Children with Autism Spectrum Disorder
No full textThe purpose of this project is to develop a method that can be utilized by educators who work with children with autism spectrum disorder (ASD). Literature related to four key principles including (a) trauma-informed care (TIC), (b) neurodiversity, (c) strength-based approaches, (d) relationship-based approaches, will be reviewed. The method is titled TIC TAAC TOE, an acronym representing trauma-informed care (TIC), teaching and advocating for children (TAAC), and teaching others engagement (TOE). This method was developed with the intent to support the integration of children with ASD into the general education classrooms and the process of implementing this approach in educational settings is further detailed. Part of this project itself, was the development of an in-service presentation on TIC TAAC TOE that can be shared during training days at school-based settings to promote enhanced experiences for children with ASD in relation to their general education peers and educators. I reflect upon my experience researching and developing this in-service presentation and method. Additionally, I share how I have grown as a dance/movement therapist in my work at internship while utilizing TIC TAAC TOE, and I express my hopes for future implications in school-based settings for educators willing to utilize this method.M.A., Dance/Movement Therapy and Counseling -- Drexel University, 201
Variability in UHMWPE Gel Spinning
No full textGel spinning experiments focused on measuring variability in diameter within samples for 4wt%, 6wt %, and 8wt% polyethylene (PE). Also, experiments were done to study the effect of adding antioxidants to 6wt% PE. Lastly, critical velocity ratios were found with some assumptions, and the spinning operating window was created. Results suggest that the steps used for spinning give low variability and antioxidants can reduce gel degradation. The critical velocity ratio (VR) is the highest for 4wt% (VR=0.092), lowest for 6wt% (VR=2.66), and 8wt% has the middle value (VR=1.71).M.S., Chemical Engineering -- Drexel University, 201