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Subharmonic Aided Pressure Estimation (SHAPE) of Portal Hypertension
No full textPortal hypertension is difficult to diagnose at its early stage as symptoms rarely manifest until the later stages of liver disease. As pressures in the portal vein cannot be directly measured, portal pressures are estimated using the hepatic venous pressure gradient (HVPG). This is defined as the difference between the wedged and free hepatic venous pressures. Patients with an HVPG greater than 10 mmHg are at increased risk of developing varices, while patients with an HVPG above 12 mmHg are at risk of variceal bleeding (which is associated with mortality rates of 15-20 %). The current clinical technique for measuring HVPG is invasive and requires insertion of a balloon catheter via a transjugular approach into the hepatic vasculature. Noninvasive techniques such as ultrasound, magnetic resonance imaging (MRI) and computed tomography (CT) have a very poor sensitivity to portal pressure estimation and are therefore, not accurate enough to be used routinely for diagnosis of portal hypertension. Thus, an alternative accurate, noninvasive ultrasound-based procedure would be a major development in the diagnosis of portal hypertension making the diagnosis safer, quicker and relatively cheaper. Hence, the fundamental hypothesis of this project is that portal vein pressures can be monitored and quantified noninvasively in humans using contrast-enhanced subharmonic-aided pressure estimation (SHAPE). SHAPE is based on the inverse relationship between the subharmonic amplitude of contrast microbubbles (obtained by transmitting at the fundamental frequency fo and receiving at fo/2) and the ambient pressure. The hypothesis of this study is that portal vein pressures can be monitored and quantified noninvasively in humans using SHAPE. Sonazoid was the contrast agent used for this study. In the first part of this study, the effect of pulse shaping on SHAPE was studied. It was concluded that the shape of the input pulse changes the subharmonic signal generated by UCAs and also the gradient observed with changing hydrostatic pressure. There was a significantly higher correlation of the SHAPE gradient with changing pressures for the broadband pulses as compared to the narrowband pulses in both in vitro and in vivo results. The highest correlation was achieved with a Gaussian windowed binomial filtered square wave with an r-value of -0.95. One of the 3 canines was eliminated for technical reasons, while the other 2 produced very similar results to those obtained in vitro (r from -0.72 to -0.98; p12 mm Hg) had a significantly higher mean subharmonic gradient than patients with lower HVPGs (0.27± 2.04 vs -4.90 ±3.28 dB; p<0.0001). SHAPE was also used for monitoring disease progression of portal hypertensive patients. These patients had follow-up clinic visits or CT/MRI scans every 6 months and at those times a repeat SHAPE examination was performed collecting data from the portal and hepatic vein in triplicate. Liver function tests (albumin, bilirubin and coagulation panel), MELD scores and presence of ascites and varices were used for treatment response. For all the cases SHAPE findings were consistent with clinical expectations. The change in the SHAPE gradient relative to baseline decreased significantly for the responders (n=9) (i.e., implying improvement) compared to the non-responders (n=2; -4.70 ±3.27 dB vs 1.77±0.55 dB; p<0.001). Results matched the corresponding clinical outcomes of improved MELD scores, improvement in underlying cause of portal hypertension and increased bilirubin and reduced ascites indicating a reduction in portal hypertension amongst responders. SHAPE has proven to be a useful and reliable tool to predict portal pressures and also monitor disease progression in portal hypertensive patients.Ph.D., Biomedical Engineering -- Drexel University, 201
Controlling the Oxygen Evolution Reaction Activity of Tunnel Manganese Oxide via Post-Synthesis Treatment
No full textTo meet growing energy demands worldwide, both public and private entities have identified the production of hydrogen through environmentally conscious and economically viable means as a key bottleneck to the wide scale implementation of hydrogen fuel cells. One such promising route, electrolysis, requires the development of reliable catalysts to drive the sluggish and energy intensive oxygen evolution reaction (OER) and to improve the overall efficiency of the electrolysis process. Tunnel manganese oxides are attractive candidates for OER catalysis applications because of their high electrochemical activity and natural abundance, which make them fiscally appealing. Moreover, tunnel manganese oxide's open crystal structures allow for facile chemical manipulations of the cationic and anionic sublattices which in turn provides methods to control specific material attributes, such as oxidation state and vacancy concentration. In this work, acid leaching and transition metal doping approaches were investigated separately and sequentially to provide insights into how tunnel manganese oxides can be engineered on the atomic and micron scales to control OER activity.M.S., Materials Science and Engineering -- Drexel University, 201
Stability, Mobility, and Integration: A Dance/Movement Therapy Method Addressing Transitions with Adolescents
No full textThis capstone thesis project is a development of a dance/movement therapy (DMT) method in an urban charter school setting for graduating high school seniors who were identified as needing support in their transition process. These students ranged in cognitive level, abilities, and services they were receiving. The DMT method, explored the preparation stage of change model with the Laban movement themes of Stability and Mobility. It incorporated the use of journaling and visual mapping as a practice in crystallizing the movement experience and as a process for students’ individual reflection. The primary goal of this method was to explore the preparation stage of the stages of change model through movement to eventually move the students to the action stage. The literature reviewed was integrated and informed the creation of this staged method. This project includes session vignettes which describe the work that was done with students in each session. Each vignette includes a conceptualization of themes that emerged throughout sessions. Overall, this method increased awareness of the self within the transition process and provided a safe space for reflection and preparation for the future.M.A., Dance/Movement Therapy and Counseling -- Drexel University, 201
The Current Use of Art Therapy Assessments: A Thematic Analysis
No full textThis researcher asked the question, "How are different Art Therapists currently using and conceptualizing art therapy assessments?" This question was examined through a qualitative phenomenological study in which two art therapists were interviewed and data was analyzed through thematic analysis. Data analysis resulted in the identification of three major themes including, art therapy assessment current use as flexible and adaptive, adapted over the course of clinical practice, and perceptions of wider use are varied. Five additional subthemes included uses are conditional, conducted informally, axial factors assessed, value in treatment, and limitations in treatment. Participants used assessment based on factors such as their educational histories, work settings, and client populations. Composite responses from the two participants described how their approaches and formats for art therapy assessment were overall informal, as well as that the factors they assessed in clients were adaptive to key areas and needs in their treatment settings and therapeutic approaches. Due to the limited number of participants, this study established preliminary themes for much needed, further investigative research. The themes and subthemes demonstrated how two art therapists were using and thinking about art therapy assessments, and why. This study suggested that when developing further informative approaches to assessment for clinical practices, art therapists may consider how multiple impacts such as research, graduate education experiences, treatment settings and populations, and treatment team approaches influence their use. This study also discussed the need for research to further investigate how intersectional cultural identity and therapist bias may impact the current use of art therapy assessment.M.A., Art Therapy and Counseling -- Drexel University, 201
Intimacy and Social Anxiety: A Literature Review with Recommendations for Blending Cognitive-Behavioral Therapy and Dance/Movement Therapy
No full textThe purpose of this Capstone Thesis Project, which is a critical review of the literature, is twofold. First is to examine the current landscape of social anxiety in the context of intimacy. Past seminal research, as well as up-to-date research is included. The landscape of social anxiety in the context of intimacy is explored through three main categories: 1) Communication and Intimacy 2) Emotion, Cognition and Well-Being and 3) Interventions. The second purpose revolves around ideas on how to enhance current treatment protocols. These ideas are both didactic and experiential in nature, the latter of which incorporates principles from dance/movement therapy. Finally, a general reflection on the observations, as well as a reflection on the process of writing the thesis, is included.M.A., Dance/Movement Therapy and Counseling -- Drexel University, 201
SMART Grid On Chip: Infusing intelligence to on-chip energy management
No full textScaling petaflop supercomputers to exascale requires a 500x increase in FLOPS, but at the cost of only a 3x increase in the total power consumption. In addition, computing systems implemented with nanometer scale multi-gate field effect transistors are increasingly integrating heterogeneous cores, GPUs, and accelerators. The power delivery and energy management of such complex chip multi-processors (CMP) is, therefore, a challenging research task spanning across the system, architecture, circuits, and device stack. A set of on-chip energy management techniques that are similar to supply side and demand side management in a SMART grid is developed. The techniques span the circuit and system layers. Intelligence is introduced in the operation of the on-chip power distribution network (PDN) to sense variations in the computational activity across cores and reconfigure the PDN to optimize the energy efficiency. A circuit level technique that improves the energy efficiency through the implementation of under-provisioned on-chip voltage regulators (OCVRs) interconnected through a switch network is developed. An operating system level task scheduling heuristic distributes the workloads on the cores such that the required reconfiguration of the PDN is minimized. SPICE simulations indicate up to a 44% reduction in the energy consumption of the CMP. An evolving on-chip power delivery methodology where reference voltages of the OCVRs are controlled through a particle swarm optimizer (PSO) is developed. The PSO negates the effects of transistor aging and process, temperature, and power supply noise induced variation in the load circuit, OCVRs, and on-chip timing sensors. The simulation results indicate an average reduction of 35% and 5% in, respectively, the power consumption and operating temperature of the voltage domains. In addition, the end of life of the voltage domain is prolonged due to a mean reduction in the aging induced Vth shift of 40%. Novel circuit techniques to detect and set the power supply voltages and suppress power supply noise are developed. The run-time circuit techniques for power supply voltage detection and clamping are demonstrated for a heterogeneous 3-D integrated circuit through SPICE simulation of a device plane in a 22 nm technology and a power plane in a 45 nm technology. The power supply voltages of less than 1 V are successfully set and provided as a reference to an OCVR within 500 ns of initiating an active state and with variation of less than 1% in the reference voltage. Noise on the power supply is suppressed through the use of hyperabrupt p-n junction varactors as on-chip decoupling capacitors. The voltage droops and overshoots on the on chip power distribution network are suppressed by up to 60% as compared to metal insulator metal (MIM) or deep trench decoupling capacitors of the same capacitance. With approximately 42% and 15% of the data center power consumed by, respectively, the processors and the cooling system, the run-time energy management techniques developed in this thesis have significant potential to reduce the running cost of exascale data centers.Ph.D., Electrical Engineering -- Drexel University, 201
Intentional Thought Processes of Teachers Who Create Personalized Learning Pathways That Result in Improved Academic Outcomes in Reading for Students
No full textDespite years of educational reform, many students do not perform on grade level, and all graduates are not prepared to succeed in college. As a result, there has been a renewed interest in personalized learning. This qualitative case study explored the thinking and decision-making processes of teachers who implement personalized learning for students and whose students have been documented to show higher academic achievement, compared with their peers, in reading. The purpose of the research was to explore the decision-making process of selected teachers in creating personalized learning opportunities that promote student achievement. Concepts from the Bandura social cognitive theory of learning provided the theoretical framework for the investigation into how the teacher designs instruction that individualizes learning. Through intensive observation and interview, the inquiry sought to discover the answers to the following questions: (1) How do teachers integrate personalized learning into their overall vision for instruction? (2) How do teachers create approaches to personalized learning opportunities for their students? (3) How do teachers design work spaces for personalized learning? The research may identify characteristics of the thinking of teachers of high-performing classrooms that may be replicated by other teachers when implementing personalized learning pathways leading to improved academic outcomes in reading for students.Ed.D., Educational Leadership and Management -- Drexel University, 201
The Efficacy of the Do The Math Intervention in the Math Achievement of Special Education Elementary Students
No full textThe purpose of this study was to determine the efficacy of the Do The Math (DTM) intervention for increasing math achievement of elementary school students in special education. This cross-sectional, quasi-experimental study compared the performance of a group of special education students in one school district on a standardized mathematics assessment both before and after the implementation of the DTM intervention for a 60-day instructional period. The researcher also compared the growth of the same experimental group of students in special education receiving the DTM intervention to that of a control group of students in special education receiving a re-teaching of the core curriculum in the special education setting on a standardized mathematics assessment. The findings of this study indicated that the DTM intervention was effective as a treatment in improving the math achievement of students in special education and it was a more effective treatment for improving achievement in math than the re-teaching of the core math curriculum to special education student in the special education setting. The results of this quantitative study provided evidence to inform the district administrators' position regarding the intervention's efficacy to meet special education student needs and also contributed to the much-needed research on viable math interventions for elementary students in special education.Ed.D., Educational Administration -- Drexel University, 201
First-Run Syndication: The Rise and Fall of First-Run Scripted Hour-Long Syndicated Shows from 1987 to 2018
No full textFirst-run syndication is an important element of the history of television in the US. This thesis will explore that history from the years 1987 to 2018. In this thesis, a number of potential reasons will be examined, as to why the first-run syndication business in the US increased so much over the years after 1987 and then later decreased until 2018. Furthermore, this thesis will examine where that business could have potentially move to and into what direction. This will be accomplished by analyzing the shows produced for first-run syndication over the years and at the same time, look at the production of cable shows of a similar genre that have potentially replaced first-run syndicated shows.M.S., Television Management -- Drexel University, 201
Examining the Effect of the GAD-7 and PHQ-9 Instruments and Impact on Patient Referrals
No full textThe purpose of this project was to educate staff on screening tools for anxiety and depression, to consistently use these tools amongst chronic pain patients, and to examine the impact their use has on referrals to mental health. Chronic pain is a wide spread problem and is the leading chronic health care condition in the United States, greater than heart disease, cancer, and diabetes combined (AAPM, 2011). The plan was to implement a practice change to include the consistent use of measurement tools to screen for anxiety and depression and to examine their effect on the number of mental health referrals. Symptom clusters of anxiety and depression are often associated with chronic pain and one pertinent study revealed that out of 250 veterans with chronic pain that 45% screened positive for one or more of the five types of common anxiety disorders and those with anxiety disorders and had significantly higher levels of pain (Pedersen, 2013). One study took place in Michigan through telephone inquiry which determined that 21.9% of participants had chronic pain and 35% of those also had depression, amongst those were younger participants who were more likely to have both depression and chronic pain compared to just having chronic pain alone (Miller & Cano, 2009). The use of reliable tools to screen for anxiety and depression were reviewed and it was determined that when completed correctly the General Anxiety Disorder -7 (GAD-7) is deemed to be highly reliable for screening of anxiety disorders (Spitzer, Kroenke, Williams, & Lowe, 2006). Also deemed reliable for determining the severity of depression is the commonly used patient health questionnaire (PHQ-9) (Kroenke, Spitzer, & Williams, 2001). The concept is that once the standardized use of the screening tools are implemented, referrals to mental health will increase.D.N.P., Nursing Practice -- Drexel University, 201