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Breaking barriers: Guidelines in creating accessible museum experience for visitors with visual disabilities
Get PDFWhen an art museum displays objects, it relies on the visitor’s ability to see and observe. However, museums alienate audiences with visual impairments by failing to offer programs to help those visitors engage with art. This study analyzes how small to mid-size museums adapt programs and acquire resources to become more accessible to audiences with visual disabilities. An analysis of these interviews revealed that museums become more accessible if they assess current barriers, connect with their community, create tactile programs, and solicit feedback from the audience served. This research serves as a guide and provides advice for museums that want to become more welcoming to visitors with visual disabilities.M.S., Arts Administration -- Drexel University, 201
Understanding the Persistence and Navigational Experiences of Underrepresented College Students at a Private, Jesuit, Catholic University
Get PDFAlthough there has been an increase in higher education enrollment, at Catholic institutions underrepresented students are graduating at lower rates than White and non-first generation students. The lack of persistence of these underrepresented students leads to an attainment gap wider than that at other private universities. Furthermore, it contributes to the historical, educational attainment gap between marginalized -ethnic and racial minorities, low-income, and first-generation- populations and White students. A plethora of persistence and retention literature exists, but missing from the research are the authentic voices of the students from these populations, especially from Jesuit, Catholic institutions. Therefore, the purpose of this study was to explore the persistence and navigational experiences of college students from underrepresented backgrounds studying at a private, Jesuit, Catholic university. This qualitative study, using focus groups and individual interviews, was guided by four research questions. The study's 16 participants shared their academic and social integration experiences and challenges as they navigated their college environment. The data collected was transcribed and in vivo quotes used to construct codes. The analysis revealed four overarching themes and additional subthemes which demonstrate the participants' exhibit a strong sense of their identities and a grit that assists them in persisting towards the goal of graduating from college. The participants' process of becoming integrated into the University began with the establishment of connections and by becoming active participants on campus. It is their cultural identities and precollege backgrounds that impact how they adjust and cope, both academically and socially, within the college environment. They utilize cultural capital and links with others who share similar values to overcome challenges. The persistence of underrepresented students is aided by supportive relationships and their perceptions and feelings about themselves and their academic ability. Additionally, underrepresented students know where and how to find on-campus support once they acquire a sense of belonging. These findings lead to understanding that the persistence and navigation of underrepresented students are tied to their feelings of belonging and the support systems they form with peers, faculty, and staff at the institution.Ed.D., Education -- Drexel University, 201
Letting the Images Speak for Themselves: An Art Therapy Grant Proposal Project for Survivors of Torture
Get PDFEven upon resettlement, survivors of torture from refugee and asylum-seeker backgrounds often experience a range of physical and psychological consequences rooted in both pre- and post-migration factors that can worsen their mental health outcomes. As a result of torture, individuals are alienated from their personhood, sense of dignity, and intrinsic worth as a human being. The purpose of this capstone grant proposal project was to secure funding for the development of an art therapy program at the Philadelphia Partnership for Resilience, a collaborative which provides legal and social services to immigrant, refugee and asylum-seeker survivors of torture in the Greater Philadelphia region. The literature review highlighted the needs and concerns of survivors of torture, outlining the current interventions utilized in the resettlement context and providing support for the implementation of art therapy with this particular population. A letter of inquiry and a grant proposal were written to meet the criteria outlined by the van Ameringen Foundation, to secure partial funding for an art therapy program for survivors of torture. A synthesis of the literature, reflections on clinical work and on the grant writing process were offered, highlighting the importance of developing culturally sensitive and appropriate interventions for survivors of torture that circumvent the need for verbal expression.M.A., Art Therapy and Counseling -- Drexel University, 201
How do host genetics and caste shape the structured diversity of the army ant gut microbiome?
No full textThe gut microbiome of the army ant species Eciton burchellii is relatively species-poor when compared to that of other host species. Despite this, a colony of Eciton burchellii boasts a high diversity of strains of two key gut bacterial species: Unclassified Entomoplasmatales and Unclassified Firmicutes (thus far known to be army-ant specific species). One strain dominates each individual worker. The purpose of this study is to investigate possible factors involved in shaping this diversity. To address this question, I gathered two types of data. First, I sequenced the protein-coding gene rplB of Unclassified Entomoplasmatales and Unclassified Firmicutes from individual workers in 2 different colonies of Eciton burchellii to assign strains to individual workers. Second, I gathered overall gut community data (bacterial species present and their relative abundances) for these ants. I then compared these data between patrilines (groups of ants from the same “father”) to assess the possible role of host genetics in shaping the army ant gut microbiome. I found a very high diversity of strains for both bacterial species, especially Entomoplasmatales. However, there was no strong evidence for host genetics having a major effect on the strain present or the community profile of an ant. Unexpected patterns suggested that the strain of Firmicutes found in an individual may be partially dictated by the caste of the ant. In addition, community profiling showed that another microbe, Weissella, was found most often in the largest caste, the soldier. The patterns uncovered reveal caste may play a major role in shaping the diversity of the army ant gut microbiome. It is also likely that transmission of microbes between members of a colony (social transmission) in conjunction with the swarm colony founding behavior of army ants contribute to the patterns of diversity observed. Overall, more sampling would aid in uncovering factors responsible for shaping the army ant gut microbiome.M.S., Biological Sciences -- Drexel University, 201
FPGA-Based Reconfigurable Physical Layer Architecture for Wireless Applications
No full textThere have been increasing developments in the area of wireless communications based on orthogonal frequency division multiplexing (OFDM). These standards are widely used for their resilience to frequency selective fading and inter symbol interference. OFDM derives this ability through dividing the overall frequency spectrum into smaller narrowband carriers which undergoes manageable and correctable fading through the wireless channel. With the increasing demand to maximize the use of the wireless spectrum both efficiently and securely, there has been significant research in the areas of cognitive, adaptive and secure wireless communication techniques across all the layers of the protocol stack. This dissertation mainly focuses the research developments targeting the physical or baseband layer. Research in these areas that are purely based on software implementations solutions benefit from faster development and turn around times but lack the ability to be tested and validated in real time scenarios as is possible with hardware based solutions. Thus an ideal implementation would be one that incorporates the flexibility offered by software and the real time speed offered by hardware. The flow of data within hardware-implemented baseband kernels is inherently predictable for all communication standards, which helps designers build fast, synchronized and optimized baseband kernels on FPGAs. However off-the-shelf FPGA based SDR architectures often strongly adhere to the few specific standards they are built for and thus are hard to change (in terms of coding rates, modulation, and subcarrier sizes) without substantial effort due to synchronization and data-rate issues. In this dissertation, we develop a programmable and flexible hardware implementation of the physical layer across wireless communication systems that use OFDM techniques. We have developed an OFDM pipeline comprising of all generic physical layer stages in which each stage can be configured at design time or at run time to accommodate different standards as well as different configuration settings within a standard. This flexibility is achieved by designing the overall pipeline to be insensitive to the latencies incurred by individual stages using the concept of state-aware stalling functionality and also with the use of infused control data for shepherding payload across the pipeline. Such a pipeline can be easily used as a research platform to experiment with different OFDM standards as well as for rapid prototyping purposes. The overall system and its performance is characterized in terms of functional correctness, area cost of implementation and flexibility. Experimental and simulation results are obtained and analyzed for the IEEE 802.16 WiMAX and 802.11a/n standards under different coding rates (1/2 and 3/4), modulation schemes (4QAM and 16QAM), and symbol sizes (128 and 64 sub-carriers), all within a common framework that does not require re-synthesis or recompilation because of the inherent capability to perform packet by packet reconfiguration. We also show results on how the flexibility built into the architecture makes it possible to implement non-contiguous OFDM (NC-OFDM) which enables the utilization of sub-carriers efficiently around noisy frequency bands by nulling and avoiding those bands while data is loaded. Keeping the ever growing relevance of cognitive radio research in view, we also built our system to also be flexible in settings user defined inter-packet and inter-frame spacing which comes into prominence in research dealing with adaptive modulation and re-configurable antennas. To further solidify the advantages of the system we built over other platforms we describe two physical layer security techniques that we built that no other hardware based testbeds currently available can implement without significant implementation effort. The first application utilizes the flexibility built into the testbed's packet organization and packet detection modules to be able to modify the wireless packet preamble enabling wireless transmissions between intended parties to go undetected to intruders. The second application utilizes the flexibility built into the interleaver module enabling it to interleave and de-interleave data based on secret keys known only to the intended communicating parties preventing intruders from decoding packets.Ph.D., Electrical Engineering -- Drexel University, 201
Numerical Study of a Mixing Flow of Gas and Liquid in Hydrocyclone
No full textHyrocyclones are commonly used for the separation of minerals from the mixture of liquid and suspended solids such as in the mixture of water and sand. In the present study, the hydrocyclone consisted of two different inlets such as liquid inlet and gas inlet and one outlet for the mixture of liquid and gas, and its geometry includes two different scales of reactor dimensions. Introducing gas while the hydrocyclone was in operation brought a new understanding of the hydrocyclone study. The optimization of the hydrocyclone operation for different gas flow rates and different water pressures was conducted in order to learn the effect of such different parameters on the vortex generation inside the hydrocyclone. These different parameters were used as the boundary conditions for the present numerical simulation and have impacted on the magnitudes of pressure, fraction, velocity streamlines, tangential velocity and axial velocity field distributions. All the simulations given in the present study were calculated with Fluent of the ANSYS 17.2 package program. k-ϵ model was applied for all the calculations with the volume of fluid (VOF) algorithm with no-slip conditions. The numerical study resulted in the results in six different cases with the combination of two sets of boundary conditions of 3 cfm, 9 cfm, 12 cfm, 15 cfm with 1psi gas inlet flow rates; and 100 gpm and 20 gpm with 15 psi, 20 psi and 25 psi water inlet pressures. Changing the gas flow rates with a constant water pressure had a significant impact on the vortex generation inside the hydrocyclone. However, changing the water inlet pressures with a constant gas flow rate did not have any effect on the development of the swirl flow inside the hydrocyclone.M.S., Mechanical Engineering and Mechanics -- Drexel University, 201
Reducing Polypharmacy in Long-term Care Units
No full textBackground: Polypharmacy is prevalent in nursing home residents and has been associated with negative outcomes such as falls, adverse events, cognitive and functional decline, non-adherence, hospitalization and even death. Despite interventions focused on reducing use of inappropriate drugs in elderly people there is still a need to create a process to safely and effectively reduce polypharmacy in this population. A systemic tapering or discontinuation of unnecessary medication called deprescribing has been documented to decrease polypharmacy and exhibited encouraging results in improving patient outcome in nursing home residents. Purpose: To implement a deprescribing process with the goal of tapering or discontinuing unnecessary medications and evaluate the effect of deprescribing medication to the functional status of elderly living in long-term care facility. Method: A one group pre-test and post-test quasi-experimental design was used to determine differences in functional status and number of medications at baseline and 6 weeks after the implementation of the deprescribing process among older adult residents of a long term rehabilitation facility. Functional status was measured using the modified Katz Activities of Daily Living (ADL: Katz). Patients’ responses to the discontinuation of medication were documented for 4 weeks. Data were analyzed using descriptive statistics and paired - test. Results: 25 older adults participated in the study. The majority are women ((76%) with a mean age of 84.8 years and average number of prescribed medicine was 9.52 (SD = 4.3). The results showed a significant decrease in the number of medications from baseline and 6 weeks (t = 2.17, p = .007) There was no significant difference (t = 2.06, p = .32) in functional status at baseline and 6 weeks. Conclusion: Deprescribing process in older adults is feasible without adverse effects. Despite the small sample size and short study duration it is encouraging to observe that a patient-centered deprescribing process can safely reduce the number medicines consumed by elderly residents in nursing home without any adverse effect.D.N.P., Nursing Practice -- Drexel University, 201
Characterization of the Mitochondrial DNA Polymerase in Plasmodium falciparum
Get PDFSeveral anti-malarials in clinical use and under development act on the mitochondrial electron transport chain (mtETC) of malaria parasites. The mtETC is an essential process requiring three proteins encoded by the mitochondrial DNA (mtDNA): cytochrome c oxidase subunits 1 and 3, and cytochrome b. The mitochondrion of P. falciparum relies on nuclearly encoded machinery for the replication, transcription and translation of the mtDNA. A candidate nuclear gene encoding mitochondrial DNA polymerase (mtDNAP) has been identified in P. falciparum. However, to our knowledge this gene has not been characterized. Due to the essentiality of the P. falciparum mtETC as demonstrated by previous studies, mtDNAP is assumed to be essential for parasite survival. Using single crossover homologous recombination, we have derived transgenic blood stage parasites with their endogenous mtDNAP locus tagged with TetR-DOZI aptamers. These transgenic parasites were used for conditional knockdown studies, demonstrating a successful knockdown of mtDNAP. Surprisingly, this was not accompanied by any change in parasite growth. Further analysis of the mtDNA from knockdown parasites revealed a decreased amount of mtDNA, consistent with at least partial knockdown of the mtDNAP. This study demonstrates that P. falciparum parasites can survive with a significantly decreased mtDNA, allowing opportunity for future studies.M.S., Microbiology and Immunology -- Drexel University, 201
Modeling of frictional forces during bare-finger interactions with solid surfaces
Get PDFTouching an object with our fingers yields frictional forces that allow us to perceive and explore its texture, shape, and other features, facilitating grasping and manipulation. While the relevance of dynamic frictional forces to sensory and motor function in the hand is well established, the way that they reflect the shape, features, and composition of touched objects is poorly understood. Haptic displays -electronic interfaces for stimulating the sense of touch- often aim to elicit the perceptual experience of touching real surfaces by delivering forces to the fingers that mimic those felt when touching real surfaces. However, the design and applications of such displays have been limited by the lack of knowledge about what forces are felt during real touch interactions. This represents a major gap in current knowledge about tactile function and haptic engineering. This dissertation addresses some aspects that would assist in their understanding. The goal of this research was to measure, characterize, and model frictional forces produced by a bare finger sliding over surfaces of multiple shapes. The major contributions of this work are (1) the design and development of a sensing system for capturing fingertip motion and forces during tactile exploration of real surfaces; (2) measurement and characterization of contact forces and the deformation of finger tissues during sliding over relief surfaces; (3) the development of a low order model of frictional force production based on surface specifications; (4) the analysis and modeling of contact geometry, interfacial mechanics, and their effects in frictional force production during tactile exploration of relief surfaces. This research aims to guide the design of algorithms for the haptic rendering of surface textures and shape. Such algorithms can be used to enhance human-machine interfaces, such as touch-screen displays, by (1) enabling users to feel surface characteristics also presented visually; (2) facilitating interaction with these devices; and (3) reducing the need for visual input to interact with them.Ph.D., Electrical Engineering -- Drexel University, 201
The Design of Printed Hybrid Constructs to Serve as Cartilage Templates for Bone Repair
Get PDFWith an estimated annual incidence of over 2.2 million cases across the world, critical size bone defects pose an unmet challenge requiring improved therapeutic strategies. Current clinical solutions, namely autologous and allogeneic grafts, are associated with a number of complications which include supply shortage, donor site morbidity and immune rejection. Given the poor vascularization observed with bioresorbable bone template scaffolds, some have turned to engineering the endogenous repair pathway by developing implantable cartilage templates susceptible to the bone transformation process known as endochondral ossification seen in native defects. Yet considerations relating to the implants' mechanical behavior, porosity and swelling, all of which are crucial to mimicking the endochondral ossification process, remain largely unaddressed in past studies. Through a parameter-driven preliminary study, we have devised a method to improve spatial resolution and property modulation by incorporating additive manufacturing into the fabrication process of cartilage templates destined for ossification-mediated defect repair. Based on our findings that hydrogel extrusion introduces structural discontinuities leading to excessive swelling and time-dependent mechanical deformation, we advance a biofabrication method involving (1) the 3D printing of a porous hybrid construct comprised of a stiff polycaprolactone network interwoven with sacrificial poly(ethylene glycol) material, (2) the casting of a cell-laden hydrogel material into the primary porous network, and (3) the evacuation of the sacrificial poly(ethylene glycol) material to create a secondary porous network. The architecture of the generated templates was modulated by varying the widths of the secondary pores and hydrogel struts. Generated templates were subjected to geometric analysis by photography, porosity evaluation by micro-computed tomography, stress relaxation testing and a swelling study. The incorporation of a stiff network constrained swelling by more than half, while decreased porosity-to-hydrogel content ratios mitigated time-dependent deformation.M.S., Biomedical Engineering -- Drexel University, 201