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Beyond self-report: Construction and validation of the Implicit Test of Antisocial Attitudes
No full textAntisocial attitudes have been identified as a powerful predictor of criminal behavior, but currently-existing measures for these all rely on individuals to accurately self-report their attitudes, which they often have incentives not to do. The Implicit Test of Antisocial Attitudes (ITAA) is an adaptation of the Implicit Associations Test (IAT) which attempts to address this shortcoming by measuring antisocial attitudes without relying on examinee self-report. The current study describes the construction and derivation of the ITAA, and examines the reliability and validity of the ITAA using responses from a justice-involved sample of incarcerated men and a non-justice-involved sample of men and women in the community. Results are broadly favorable for the psychometric characteristics of the ITAA. Implications and directions for future studies are discussed.Ph.D., Psychology -- Drexel University, 201
Finding Freedom: Development of a dance/movement therapy method for children with cerebral palsy
No full textThe purpose of this capstone project is to develop a dance/movement therapy method that encourages freedom of expression for children with cerebral palsy. “Finding freedom” encourages movement, extension, and relaxation for clients with severe cerebral palsy who do not often have the opportunity to express themselves through movement outside of their wheelchair. The method involves creating safety through the therapist offering both physical and emotional supports before transferring a student from a wheelchair to the floor. Once on the floor, the therapist supports exploration and expression of movement through mirroring, breathing, and attunement. This method developed organically and was introduced after the therapist and the client developed a therapeutic relationship based on comfort, trust, and understanding.M.A., Dance/Movement Therapy and Counseling -- Drexel University, 201
Development of the Therapeutic Relationship in Music Therapy with Adolescents with Autism Spectrum Disorder: A Contextualized Case Analysis
No full textThis capstone will first provide a brief overview of autism as well as literature regarding the following: the use of music therapy, particularly improvisational methods, for individuals with autism; the therapeutic relationship, as well as its role in the music therapy and non-music therapy treatment of autism; and characteristics existent in music therapy that influence the therapeutic relationship, including intersubjectivity, affect attunement. A case study will then be reviewed in order to explore this topic within a specific context—the author’s developing musical therapeutic relationship with a client diagnosed with ASD in individual music therapy. Finally, the author will identify personal reflections gained from the clinical experience, analysis, and overall process, discuss these reflections as they pertain to the literature, and make recommendations for clinical practice based on these findings.M.A., Music Therapy and Counseling -- Drexel University, 201
Ions in MXene: Characterization and Control of Interlayer Cations and their Effects on Structure and Properties of 2D Transition Metal Carbides
No full textMXene, a new family of materials comprised of ternary carbonitrides of the early transition metals, has exploded into the field of two-dimensional materials since their discovery in 2011. They draw interest due especially to their unique combinations of hydrophilicity and high electrical conductivity with extremely large compositional variability. Since their introduction, they had been explored in applications of ion-intercalation-based energy storage, i.e. lithium-ion batteries and electrochemical capacitors (supercapacitors), and had been hailed as 'conductive clays', but no major work had been undertaken to provide a more detailed picture of the structural effects of chemically-intercalated ions and what exactly 'clay-like' behavior meant in the context of MXene. This work endeavored to fill this gap in the literature, focusing primarily on Ti3C2Tx, the most well-studied MXene (where T is a variable surface termination of the nanosheets). Based on a review of various literatures, we define 'clay-like' properties to include intercalated ions that are exchangeable and that can influence dynamic structural responses to the host material to stimuli, based on the chemistry of the intercalated ions. We successfully intercalated, by chemical means alone, cations of alkali metals (Li+, Na+, K+, Rb+, Cs+), alkaline earth metals (Mg2+, Ca2+), transition metals (Mn2+, Fe2+, Co2+, Ni2+), and alkylammonium cations of the form [(CH3)3NCnH2n+1]+, where n ranges from 1 to 16. We have also demonstrated control of exchange of initially-intercalated cations to other cations; X-ray photoelectron spectroscopy and X-ray diffraction results confirm that the process is a true exchange, as experienced in clay minerals. For the alkali and alkaline earth metal cations, we have found that the basal planes of the host MXene expand and contract their interlayer distance when H2O enters and leaves the structure, and that the magnitude of this response correlates with the hydration enthalpy of the intercalated cation. This is a quantitative link to the same phenomena experienced in clays. The transition metal-intercalated samples also demonstrated similar expansion from intercalated H2O. In addition, in Ti3C2Tx without added cations, we found an effect of pseudonegative compressibility along the c axis; that is, when pressure was applied in the presence of H2O, the basal spacing expanded. This was determined to be due to the forced intercalation of H2O, and the presence of intercalated K+ was found to hamper this effect. Such expansion was known in the literature of other materials, but we have found shearing of the nanosheets with respect to one another to be a potential cause. For the alkylammonium cation-intercalated samples, we observed a discontinuous expansion in the basal spacing correlated to the chain length of the intercalated organocations; this was quantitatively described both by simple volume-packing arguments as well as by more sophisticated computational results. This further led to a determination of the ion-exchange capacity of Ti3C2Tx. The results were found to be analogous to those of the clay minerals, providing further strength in the connection between MXenes and clays. Finally, the intercalation of alkylammonium cations was expanded to both Ti2CT2 and Nb2CTx, to demonstrate compatibility and universality with both changes to n (of Mn+1XnTx) as well as with changes to the transition metal M; these samples demonstrated the same kind of discontinuous expansion in basal spacing.Ph.D., Materials Science and Engineering -- Drexel University, 201
Tunable RF Circuits using Iron-Cobalt Ferromagnetic Nanoparticles
No full textModern communication systems are evolving very quickly and tunable Radio Frequency (RF) components are needed to utilize the spectrum more effectively. Recent developments in small size and tunable microwave/RF components are attractive for communication and radar applications for industrial, civilian, and military purposes. Different frequency tuning methods of electrical, mechanical, optical, acoustic, and magnetic are employed for dual frequency of operation. New manufacturing methods are being continuously improved with great interest in additive manufacturing. This PhD thesis work focuses on design and frequency tuning of passive RF circuits using magnetic flux control of ferroic nanomaterials fabricated using additive manufacturing. In particular, the focus of the thesis is using nanoparticles of ferromagnetic Iron-Cobalt (Fe60Co40) and Cobalt ferrites (CoFe2O4) considered for their electromagnetic properties. Compared to ferroelectric materials, the tuning control circuit of ferro/ferrimagnetic materials can be designed without adding parasitic effects. The extracted electromagnetic properties of the realized composites are refraction index of nFeCo=4 and nCoFeO=2, magnetization saturation of MFeCo=198 emu/g and MCoFeO=46.8 emu/g, loss tangents of tanδFeCo<0.25 and tanδCoFeO<0.09, and coercivity of HFeCo=158 Oe and HCoFeO=900 Oe; which makes them viable at microwave frequencies and many RF applications.
The FeCo composites were synthesized and fabricated on FR4 substrate using subtractive manufacturing through milling machine and additive manufacturing using squeegee printing. The approximate electromagnetic properties of FeCo were extracted over a broadband of 1-10GHz using perturbation theory applied to microstrip transmission lines. Then these initial estimates were further refined using annular ring resonance structure for accurate extraction over a narrowband frequency of 1-4 GHz, which is applicable for Wi-Fi application. Full electromagnetic field modeling of annular ring resonator was also developed to best curve fit the initial seed values from perturbation technique to the measured 2-port scattering parameters. My realized extraction procedure employs the Finite Element Method (FEM) based electromagnetic field modeling using the commercially available numerical modeling (e.g., COMSOL Multiphysics and Ansoft HFSS) and experimental measurements of the S-parameters using 8722ES Network Analyzer.
The extraction is performed for baseline annular ring design and FeCo nanoparticle based composite substrate with and without applied magnetic fields from 0-1500G. The extracted results of the FeCo range in permeability from ur=15 and tanδu=0.25 to ur=10 and tanδu=0.1 with applied 1.5kG magnetic field. Accurate extraction with anisotropic behavior was used to realize tunable antennas, tunable impedance matching circuits, and tunable 3rd order annular ring and hairpin filters at different frequency bands. The fabricated annular ring 3rd order filter resulted in 200MHz (8%) tuning when 1.5kG magnetic field was applied at Wi-Fi band of 2.4GHz, while the tunable antenna resulted in 100MHz tuning with the same applied field.
Furthermore, additive manufacturing is used to resolve some of the fabrication challenges encountered with subtractive methods. Characterization is performed using annular ring resonators for Polylactic Acid with the extracted εr=1.9 and tanδε=0.02 material that is used for additive manufacturing along with magnetic CoFeO with ur=2.3 and tanδu=0.09 nanoparticles. 3D printed magnetic filament material is used to design tunable phase shifter with about 16° phase shift with applied magnetic field operating at C-band frequencies. Additional analysis using CoFeO is provided for tunable periodic structures with about 8x magnification compared the nonperiodic case. Meanwhile, a bandstop with 1.25GHz bandwidth exists at 6.25GHz. Moreover, at 5.74GHz there is about 40° phase shift for the periodic structure compared to the non-periodic baseline case since the wave is slower. Future applications of this magnetically tunable circuits are considered for tunable idler, periodic structures, impedance transformers, and frequency selective surfaces.Ph.D., Electrical Engineering -- Drexel University, 201
Probing Cosmic Ray Anisotropy with Atmospheric Neutrinos
No full textIn the hundred years that have followed the discovery of cosmic rays, more about them remains unknown than known. Many concerted efforts are currently underway to detect cosmic rays using a variety of detection methods in space, on the surface of Earth, and deep underground. Of the many remaining mysteries, the one addressed in this work is the anisotropy in arrival directions of the cosmic rays incident on the atmosphere. This behaviour has been observed in both hemispheres of the planet, at high significance, from 1 TeV - 1 EeV energy ranges, at angular scales from 5 degrees to 180 degrees, and displays no time variation. It is measured consistently as a 0.1% over- and under-fluctuation. This work presents the first neutrino analysis of cosmic ray arrival directions so far, specifically, in the northern hemisphere. The analysis is done with an atmospheric neutrino dataset which was specifically designed for this analysis and composed of neutrinos detected by the IceCube South Pole Neutrino Observatory from 2011-2016. The goal of the search was to detect cosmic ray anisotropy as observed in atmospheric muons, but this time, in atmospheric neutrinos. To this end, a new atmospheric neutrino dataset was created using machine learning, aiming to increase data acceptance rates by optimizing sacrifices in purity and angular acceptance. The standard analysis techniques were carried out, along with a new log-likelihood method developed to improve sensitivity in a lower-statistics realm. While no signal was detected in this analysis, the analysis methodology has been developed and tested. We project that with a total of twelve years of IceCube data will be required to be sensitive to a dipole anisotropy at the level previously reported by the Tibet-ASγ Collaboration. Detection of cosmic ray anisotropy in the neutrino channel would allow for verification of known cosmic ray shower physics, and particle propagation. The neutrinos could allow us to probe the anisotropy in a new way. If the signal deviates, there could be new physics to discover. The method and data selection are developed, and in several years, new developments will be made towards unraveling the mystery of cosmic ray anisotropy with neutrinos.Ph.D., Physics -- Drexel University, 201
Impact of Ventilation: Creating a Healthy Indoor Environment by Understanding the Impact of Ventilation on Indoor Air Quality in Commercial Buildings
No full textVentilation plays a significant part in building dynamics, affecting building energy consumption and indoor air quality (IAQ) in complex and often conflicting ways. Ventilation standards often prescribe minimum ventilation rates (VRs) in a one-size-fits-all manner that ignores the unique impact ventilation has on different buildings. This Thesis investigates the existing knowledge of ventilation outcomes to develop a customizable ventilation control strategy that would result in specific, predicted ventilation outcomes. The ways in which ventilation may affect building energy use and IAQ were explored through a literature review and three research objectives were established to develop this strategy. The first objective included an exploration of the impact that ventilation has on the indoor concentration of atmospheric contaminants. While ventilation can introduce these harmful pollutants indoors, the most potent of which (particulate matter) can be much more effectively controlled by improved filtration. It was further shown that filtration becomes more efficacious that higher VRs. The second objective was designed to create a methodology that would allow one to optimize daily VRs based on desired outcomes. This was done by constraining energy cost to levels currently achieved using an existing ventilation strategy and optimizing positive IAQ outcomes of introducing more outdoor air—which is generally considered cleaner than indoor air—indoors based on building parameters, climate, and user preferences. Thus, the premise of this ventilation strategy was to improve IAQ to a theoretical optimum by introducing more fresh air indoors at no additional energy cost. Potential ventilation outcomes were shown on a Pareto frontier that represents a tradeoff between energy use and IAQ. Pareto optimized VRs were shown to be weather dependent, and a method to generate predictive models to estimate optimal ventilation based on outdoor conditions was developed. In the third objective, a control scheme was developed to implement the proposed ventilation strategy in real buildings using a CO2-based demand-controlled ventilation approach. This optimization and control scheme was implemented in a virtual testbed emulating ventilation control in a real building. Overall, ventilation was successfully maintained at target levels, except for when very low VRs were desired, where damper leakiness, infiltration, and CO2’s slow buildup indoors impeded proper control. An analysis of the implementation this ventilation strategy over the entire small-to-medium-large U.S. office sector found that it can improve occupant productivity by improving IAQ by 1.3% on average, or an equivalent 0.1 billion for the entire sector.Ph.D., Architectural Engineering -- Drexel University, 201
Predictive Analytics on Real-Time Biofeedback for Actionable Classification of Activity State
No full textContinuous biomedical monitoring has the potential to improve quality-of-care for patients as well as working conditions for medical practitioners over the current state-of-the-art. Currently, Emergency Medical Technicians in the field carry monitoring equipment that can weigh over 50 lbs, and manually communicate information back to hospital physicians. For patients, medical monitoring is carried out using tethered equipment that must remain attached for hours or days, and must be removed when the patient must get up to walk or use the restroom. Data lapses during these disconnected breaks can be misinterpreted by medical staff as a medical event, and true medical events can be missed as a result of non-monitoring. Further, being still for extended periods of time can exacerbate the very risks being treated, due to the increased risk of a blood clot while remaining stationary during monitoring. Radio Frequency Identification (RFID) technology is traditionally used as a battery-free chip embedded into an item for inventory management. As the chip is placed within the field of an RFID interrogator, one or more interrogation waves are reflected off of the chip and observed at the interrogator site. The reflected signal is encoded by the chip with an identifier which is typically used for inventory purposes. Multiple interrogation signals are typically employed to overcome collisions and to ensure that a viable interrogation takes place while the chip is in range of the interrogator. We take advantage of this property of RFID technology by knitting a metallic antenna around the tag and embedding the system into a wearable garment in an unobtrusive way. We re-purpose the use of RFID by observing small perturbations in the physical properties of the reflected signal for each interrogation of the tag. As the wearer moves about, changes in the knit antenna shape result in changes to the properties of the reflected signal as it is regularly and frequently polled by the interrogator. These physical changes are small and subject to noise interference both from RF, movements in the environment around the subject, and movements by the subject directly; however, we fuse signal processing and machine learning approaches to estimate biomedical properties of the wearer such as respiratory rate, apnea, uterine contractions, and stationary limbs. As a result, we introduce a wearable technology platform supported by real-time analytical software that enables unobtrusive, continuous, ambulatory monitoring of strain or movement biomedical artifacts.Ph.D., Computer Engineering -- Drexel University, 201
Faithfully Fit—Mind, Body, and Soul: Music Therapy Partnering with Lifestyle Education
No full textCould music therapy interventions applied in a short-term group setting be effective in supporting the relational, economic, political and socio-cultural challenges to sustaining healthy lifestyles that participants face when returning to their domestic environs? This capstone project was initiated because of a query from the director of a church-operated lifestyle/health retreat and a concern for the increased effectiveness and sustainability of healthy lifestyles post-retreat. The annual retreat is open to any and all, regardless of creed or ethnic origin, and about sixty campers plus staff members came from around the world and across the United States. The predominant ethnicity of retreat participants was of African descent, the predominant gender was female. Participants ranged in age from 13 to 88, and most had some religious affiliation. The dominant health issues were obesity, diabetes, and cardio-vascular diseases. The purpose of this capstone project was to identify, develop and implement music therapy group sessions that would help support the continuity of healthy lifestyle changes beyond the two weeks of intense health education and fitness training. The interventions and sessions were focused on 1) enabling lifestyle retreat participants to initiate and support self-reflection, resulting in a personalized healthy lifestyle plan; and 2) using music and group support to develop tools for sustaining healthy lifestyle choices and post-retreat networking. Processes included psychoeducational presentations, general music therapy interventions, a camp choir, and spiritual components as part of the music therapy experience. Daily workshops were structured with a whole group experience that would have a spiritual/psychoeducational foundation regarding neuroscience and the mental and emotional components of changing lifestyle habits, supported by small group exploration and application. The allotted time, the general physical and probable spiritual characteristics of the participants, the specific goals request from the retreat director, and the body of research information accessed contributed to the decisions regarding the development of the sessions and the interventions chosen for this project. Sessions included socially engaging music improvisations using a variety of hand and melodic percussion instruments. Experiences from this project demonstrated that the mental, physical and spiritual responsiveness to music supports a rationale for using music and music therapy in stress management. The combination of community music therapy and the psychoeducational instruction regarding mindfulness, positive psychology, and cognitive-behavioral discussions appeared to connect with the variety of learning styles inherent in a large group. Project findings validate other literature that recommends holistic approaches as opposed to focused and compartmentalized approaches to growth, change, and other areas of lifestyle development. Music therapy introduced novelty to the programming, an opportunity for some to revisit or discover interests in playing instruments new to their experience, the chance to sing in a choir after years of non-participation, and the opportunity to give of oneself in sharing their musical expression. According to participant comments, elements of music therapy enhanced and assisted in the creation of their sustainability plan.M.A., Music Therapy and Counseling -- Drexel University, 201
Workplace Violence in Emergency Departments: Addressing Barriers to Reporting Through Education
Get PDFBackground: Workplace violence (WPV) in emergency departments is a national health care concern. Nurses practicing in emergency departments are at greater risk for violence than other health care professionals. Published literature suggests that WPV is underreported because of inadequate understanding of its definition and associated reporting processes, which contributes to a lack of evidence-based interventions to reduce its frequency. Purpose: Consistent utilization of a reporting database can assist in identifying trends in emergency departments’ violence occurrences and subsequent interventions, as reviewed by the organization’s WPV Committee. WPV education was offered with the intent of improving reporting accuracy and promoting better understanding of WPV. The WPV Committee’s lack of engagement was addressed. Methods: Emergency department employees and leaders were offered education on the definition and reporting process of WPV through a free continuing nursing education module. The WPV Committee was simultaneously tasked with updating policies and creating engagement strategies to reduce WPV. Evaluation: Reporting system effectiveness was measured by comparing the frequency of documented occasions of violence before and after an educational intervention. Continuing nursing education pre- and posttest score comparison via paired t test was used to gauge WPV and reporting process knowledge. The WPV Committee’s participation was increased. Clinical Implications: Utilization of a consistent WPV definition and reporting process aided accuracy of incident reports, exemplifying a culture that supports reporting incidents. This practice can inform data-driven interventions, when funneled through the WPV Committee, to reduce WPV, and may contribute to a safer emergency department environment for employees.D.N.P., Nursing Practice -- Drexel University, 201