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Button Making: Developing a Relational-Cultural Art Therapy Method For and In Third Spaces
No full textThe development of this method explored how art therapy can be applied differently when the space and system in which it is practiced focuses on power-with dynamics, connection, and empowerment. This was explored through an integration of alternative art therapy practices and relational-cultural theory. The development of this method aimed to support connection, facilitate access to art making, and work from a position of empowerment through power-with rather than power-over dynamics. Third spaces were utilized as an ideal place of practice for this method due to their relational quality and tendency towards a collective sense of ownership and access. Button making was the art process mobilized for this method due to the history of buttons as a visual tool for collective messaging, personal and community identification, organizing, and empowerment.M.A., Art Therapy and Counseling -- Drexel University, 201
Light-Driven Polymeric Bilayer Actuators Fabricated by 3-D Printing
No full text4D printing is an emerging additive manufacturing technology that combines the precision of 3D printing with the versatility of smart materials. 4D printed objects can change their shape over time with the application of a stimulus (i.e., heat, light, moisture). Light driven smart materials are attractive because light is wireless, remote, and can induce a rapid shape change. Herein, we present a method for fabricating polymeric bilayer actuators via 3D printing which reversibly change their shape upon exposure to light. The photoactive layer consists of a poly(siloxane) containing pendant azobenzene groups. Several different photoactive polymers were synthesized, to study how substitution of the benzene rings affected the properties of the active layer polymers and the bilayer actuators. The photomechanical effect displayed by the bilayers was evaluated quantitatively. These bilayers exhibit rapid actuation with full cycles completed within seconds, and photo-generated stresses ranging from 1.03 - 1.70 MPa.Ph.D., Chemistry -- Drexel University, 201
Physical Defects and Degradation Mechanisms of GaN-based Electronic Devices Explored by Transmission Electron Microscopy
No full textThe maturation of new semiconductor and device technology is dependent upon our understanding of device reliability. Silicon has had the benefit of more than 50 years of science, engineering, and statistics, leading to an incredibly mature and robust material platform. Newer device platforms, like GaN, represent exciting new prospects but their technology has yet to mature to reach Si's level reliability. While the properties of GaN devices exceed those of conventional Si- or GaAs-based devices, widespread adoption of GaN technology has been slow due to insufficient understanding of its reliability and device degradation mechanisms. This thesis investigates the degradation mechanisms of GaN-based devices using high-resolution electron microscopy. Transmission electron microscopy (TEM) and scanning-TEM (STEM) are combined with spectroscopic techniques including electron energy-loss spectroscopy (EELS) and energy dispersive x-ray spectroscopy (EDS) to reveal the microstructural evolution of stressed GaN devices. Collectively this work illustrates the importance of physical characterization on developing semiconductor systems. While the vast majority of device characterization is driven by electrical characteristics, the microscopic characterization of devices is an excellent complement to traditional techniques.Ph.D., Materials Science and Engineering -- Drexel University, 201
Broad and Narrow Intrinsic Absorption in Quasars as it Relates to Outflows, Orientation, and Radio Properties
No full textThis work provides evidence that a large fraction of narrow absorption lines (NALs) seen along the line of sight to distant quasars are due to accretion disk winds, while also seeking to understand the relationship between NALs and certain quasar-intrinsic properties. We extend the results from past work in the literature with velocity distributions (dN/d[beta]) of ~ 108,000 NALs from a sample of ~ 58,000 Sloan Digital Sky Survey (SDSS) quasars. The primary results of this work are summarized as follows: (1) the velocity distribution of NALs is independent of radio loudness (or even detection) once marginalized by optical/UV luminosity; (2) there are significant differences in the number and distribution of NALs as a function of both radio spectral index and optical/UV luminosity and these two findings are not entirely interdependent; (3) improvements in quasar systemic redshift measurements, analysis of NALs in broad absorption line quasars, and differences in the NAL distribution as a combined function of optical luminosity and radio spectral index---together provide evidence that a significant portion of NALs are due to quasar outflows; (4) the results are consistent with standard models of accretion disk winds governed by the L_UV-[alpha]_ox relationship and line-of-sight orientation indicated by radio spectral index; and (5) possibly supports the magnetically arrested disk model as an explanation for the semi-stochastic nature of strong radio emission in a fraction of quasars.Ph.D., Physics -- Drexel University, 201
The Role of Spino-Parabrachial Neurons in post-SCI Affective Pain
No full textNeuropathic pain develops in over 80% of spinal cord injury (SCI) patients. Negative affective disorders, such as anxiety and depression, are highly comorbid with neuropathic pain and SCI. However, these emotional components of pain have not been studied in the context of SCI, nor have they been linked to spinal plasticity below the level of injury. Projection neurons in lamina I of the spinal cord relay pain information to the parabrachial nucleus (Pb), and Pb neurons project to the amygdala. While considered the neural correlate of affective pain, it is unclear as to whether the spino-Pb-amygdaloid pathway can be anatomically delineated from the sensory-discriminative spinothalamic pathway in the mouse. We hypothesize that the affective and discriminative pathways from lumbar cord are distinct in the mouse, and that incomplete SCI causes an increased cellular activity of spared lamina I spino-Pb projections to facilitate the development of negative affective behaviors. Combined retrograde tracing from the Pb and thalamus revealed no overlap in lamina I projection neurons at lumbar spinal levels, allowing for selective control. Following incomplete SCI, a subset of mice with mechanical hypersensitivity displayed a cognitive aversiveness to pain and a trend towards increased anxiety-like behaviors. Intracellular recordings from lamina I spino-Pb neurons revealed higher input resistances in mice displaying pain behaviors, suggesting an increased responsiveness to sensory input. This work provides the foundation for cell-specific manipulations to elucidate the functional roles of spino-Pb neurons in post-SCI affective pain.M.S., Neuroscience -- Drexel University, 201
Inkjet Printed Microelectrodes on Flexible Substrates and its Applications
No full textFlexible electronics have recently drawn significant attention due to its applicability in a variety of fields such as a display, solar cell, wearable electronics, and biosensor. Different fabrication techniques have been explored to realize flexible electronic devices so far. Photolithography-based microfabrication techniques have been used for various flexible substrates, but the fabrication processes are time-consuming and require a cleanroom facility and hazardous chemicals. Inkjet printing can be a compelling alternative due to its advantages such as quick turnaround (photolithography not necessary), easy processing (cleanroom not necessary), low-cost manufacturing, and low-temperature fabrication. While inkjet printing has been applied to some flexible substrates (polyimides (PI) and Polyethylene terephthalate (PET)), few researchers have studied the direct printing of conductive solutions on polydimethylsiloxane (PDMS) and polyparaxylylene (Parylene) substrates, which are widely used in MEMS, microfluidics, and lab-on-a-chip fields especially for biomedical applications. The main reason is that it is very challenging to inkjet print conductive patterns on the elastomeric and hydrophobic materials. This research is designed to overcome the challenge and develop inkjet printing techniques to create microelectrodes on flexible PDMS and Parylene substrates. This involves fundamental characterization of printing performance as a function of printing parameters. For instance, the printing resolution depends on droplet size, and droplet size is limited by the nozzle diameter, ink viscosity, and temperature. To create fine microelectrodes on PDMS, we investigated the effects of main printing parameters on the quality of printed microelectrodes and identified optimal conditions for printing. Direct inkjet printing of conductive inks on Parylene was very difficult, so we developed a novel fabrication method in which the electrode patterns are printed on PDMS first and then transferred onto Parylene through vapor deposition. This simple way, we were able to create highly flexible thin electrodes and expand application area by combining other conventional techniques. We tested and confirmed a deposition of a thin copper film on the transferred silver pattern using electroplating for improving impedance magnitude of the microelectrodes. Next, we performed a thin gold film deposition on the copper layer using electroless plating for implantable applications (ECoG and spinal prove devices) as a solution of toxicity issue. Furthermore, ArF excimer laser machining is used for creating high-resolution microstructures on the ECoG microelectrodes array application. In summary, the present study demonstrated the performance of inkjet printed microelectrodes on PDMS and Parylene substrates in two specific applications, dielectrophoresis, and electrocorticography (ECoG). The results clearly show that the flexible silver microelectrodes created by the presented method can be used for electrokinetic applications. The ECoG electrodes array were implanted in rat brains for in-vivo studies. Through the experiment, it was confirmed that the flexible microelectrodes were able to detect electrical signals from the neurons. We believe that the rapid and low-cost fabrication method of thin flexible ECoG array presented here will continue to be an essential platform for microfluidics, Lab-on-chip, flexible electronics, medical implants as well as brain-computer interfacing applications.Ph.D., Mechanical Engineering and Mechanics -- Drexel University, 201
Variety Counts: How Pursuing Self-Regulatory Goals Impacts Variety Seeking in Vice and Virtue Categories
No full textMy dissertation research explores how variety seeking tendencies differ when consumers are in pursuit of a self-regulatory goal. In general, variety is shown to increase consumption by reducing boredom and satiation. All else being equal, consumers demand and choose variety among their options to the extent that sometimes they let go of their favorite option only for the sake of having variety. In this research, I show how consumers’ perception of variety in consumption change when they are trying to achieve a goal for which they must regulate consumption. I specifically focus on two consumption domains: a) The vice domain that offers options that impede goal-progress. For a consumer who has a health goal such as weight loss, snacks that are high in sugar and fat content are examples of vice foods whose consumption is inconsistent with the goal. b) The virtue domain that offers options that facilitate goal progress. For the consumer mentioned above, vegetables high in nutritional value are examples of virtue foods whose consumption is consistent with the goal. I show that consumers primed with a health goal seek less variety when the options are goal-inconsistent (vice categories), and these choice patterns lead to lower anticipation of guilt. On the other hand, consumers primed with a health goal seek more variety when the choices are goal-consistent (virtue categories), which leads to higher anticipation of goal achievement and fulfillment. These effects emerge because a varied consumption set is perceived to contain more items than a non-varied one. When there is less variety in a consumption set, consumers tend to assimilate similar (or identical) items and perceive them as unified wholes. This will decrease the perceived quantity of the consumption set. As variety increases in a set, similarity among the items decreases, which makes it less likely for consumers to combine items. This makes a varied set of items seem to be more numerous than a non-varied one. Depending on what implications quantity of consumption has for consumer goal progress (consuming more fattening snacks is hindering goal progress but consuming more vegetables is helping it), consumers with a goal incorporate different levels of variety in their choice. I further show that these effects are stronger when consumers think about the choice prospectively than when they reflect on a past choice retrospectively.Ph.D., Marketing -- Drexel University, 201
A Duet of Symptom and Structure: A Contextualized Case Study Exploring the Relationship between Dance/Movement Therapy Structure and Emotional Manifestations of ADHD
No full textThis capstone thesis explores the degree of structure in dance/movement therapy (DMT) that best supports the emotional aspects, specifically self-esteem, of children with attention deficit hyperactivity disorder (ADHD). The literature emcompasses various elements related to the school setting, self-esteem development, and treatment approaches for these children. Case conceptualization is included on one individual, age seven, who attends a special education school and recieves individual DMT sessions weekly. The discussion is based on themes that emerged through the six week period including use of imagery and props to elicit emotions, use of open ended structure to support imaginary play, use of strict structure leading to frustration and yearning for individual expression, and increase in self-esteem due to autonmy and normailzation of symptoms. Reflection and conclusion is based on the author’s learning through the process of this project regarding the elements of the therapeutic reltionship, openness of individual expression, and the balance of input from the student and the therapist. Through understanding the emotional aspects related to ADHD, the therapist can create mind body experiences to deepen self-awareness, therefore improving behavioral problems as well.M.A., Dance/Movement Therapy and Counseling -- Drexel University, 201
Combating Racial Bias in Art Museums
No full textAmerican art museum collections and exhibitions are powerful cultural instruments. These institutions have particular significance for Black Americans because of the longstanding marginalization or outright exclusion of Black art in most mainstream museums. In this thesis I examine current efforts to correct this history of marginalization. The thesis consists of a short historical overview and the transcripts of interviews conducted with four individuals from four different generations who are deeply involved in the contemporary Black arts community and who have successfully deployed tactics to combat racial bias in American art museums. The interviewees are collector E. T. Williams Jr.; artist and gallerist Daniel Simmons Jr.; auction house employee Nigel Freeman and curator Noah Smalls.M.A., Arts Administration -- Drexel University, 201
Practicing at the Intersection of Dance/Movement Therapy & Yoga: A Modified Grounded Theory Study
No full textThe purpose of this study to clarify and describe dance/movement therapists' use of yoga in a dance/movement therapy (DMT) context. This study aims to address the current problem of limited research in the conceptualization and critique of the use of yoga in DMT, despite available literature on some dance/movement therapists' implementation of yogic elements into DMT practice. The methodology of this modified grounded theory approach includes qualitative semi-structured interviews to better understand the participants' perspectives on the relationship between yoga and DMT. Data from interviews were coded for themes using open, axial and selective coding in order to generate a visual model of findings, which resulted in the preliminary steps of conceptual ordering as the endpoint of the study. Although cultural considerations on the use of yoga in the context of DMT were explored, through the emergent nature of grounded theory methodology, an emphasis on clinical-decision making was developed. The results include an examination of how clinicians navigate the integration of yoga in DMT interventions. Nine aggregated selective codes emerged from the coding process: (1) Yoga is a part of the clinician's identity and clinical skills; (2) Factors of clinical decision-making on the inclusion, exclusion, and modification of yogic elements are foundational to a blended approach; (3) Spontaneity and improvisation are central to the session and the modification of yogic elements; (4) Yoga-related props help structure sessions and provide visual cues for developmentally appropriate and engaging movement tasks; (5) Yoga is used as a mind-body toolbox inside and outside of a session; (6) Yogic elements are modified to function outside of traditional class structure; (7) Yogic elements serve specific symptoms and treatment goals; (8) Differing perspectives on the boundaries between DMT and yoga are represented, and (9) Contraindications and/or conditional considerations are identified when using yogic elements in DMT context. These themes were explored and organized through seven figures to illuminate relationships and processes. A process model figure illustrates the three central concepts of the mind-body toolbox, modification of yogic elements, and the implementation of spontaneity/improvisation as steps in practicing at the intersection of yoga and DMT. Discussion of the results include the differences between the research aim and findings, implications for future research, recommendations for education, and clinical applications.M.A., Dance/Movement Therapy and Counseling -- Drexel University, 201