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Overexpression of Transcription Factor Specificity Protein 1 (Sp1) Results in Centrosome Amplification
No full textSp1 is overexpressed in a variety of cancers and is often associated with poor prognosis. Depletion of Sp1 results in an increase in chromosome segregation errors, which can partially be explained by Sp1 regulation of centrosome number. Dosage of centrosomal proteins is important for maintaining centrosome homeostasis in the cell. Due to the clinical relevance of Sp1 overexpression, we sought to determine the effect of Sp1 overexpression on centrosome number. Here, we report that Sp1 overexpression results in a small but significant increase in the centrosome number.M.S., Molecular and Cell Biology and Genetics -- Drexel University, 201
3-D Morphology of the Ankle Joint as Related to the Design of the Interfacing Surfaces of an Anatomically-Based Total Ankle Replacement
No full textAnkle arthritis is a painful and debilitating condition caused by abnormal wear to the cartilage covering the talocrural joint. Initially, symptoms are treated conservatively. Use of specialized ankle braces, cortisone injections, and physical therapy are used to combat pain. Once these treatments no longer suffice, non-conservative treatment must be sought. Patients choose between an ankle fusion and total ankle replacement. Foot ankle ankle surgeons often prefer ankle fusion because of the unacceptably high revision rates in total ankle replacement. One of the most common reasons for revision surgery is loosening of the ankle joint. The stock surface geometry of commercially available total ankle replacements stands in stark contrast to the complex, nuanced morphology of the talar dome and tibial plafond. As a result, large amounts of bone are resected during surgery. This is problematic because the average cortical bone thickness of the talus and tiba is very thin. Therefore, most of the implant adhesion is achieved through pins inserted into soft, cancellous bone. The design of the interfacing surface of the total ankle replacement should be based on surface anatomy to mitigate the incidence of revision surgery. As a prerequisite to this endeavor, the surface morphology of the talar dome and tibial plafond must be quantitatively defined by a set of anatomical measurements. In this study, 44 anatomical parameters are measured on the tibia and talus with the intent that they will form the basis of a subject-specific, parameter-based interfacing surface of a total ankle replacement. Distance mapping validates the merit of this process, as average deviation between the engineered surface and the anatomical surface averaged less than 0.4 mm.M.S., Mechanical Engineering and Mechanics -- Drexel University, 201
A Dance/Movement Therapy Method for the Elicitation and Use of Voice in Movement Sessions with Preschool-Aged Children with Developmental Delays
No full textThis capstone thesis presents a complete dance/movement therapy (DMT) method for intentionally considering, eliciting, and incorporating the use of sound and voice in movement sessions with preschool-aged children with developmental delay. It considers the development of voice as a form of communication and expression in relationships beginning with the first relationship between primary caregiver and infant and generalizing to other individuals later in life, including the therapeutic alliance. Knowledge gleamed from a range of literature in the fields of counseling, speech therapy, music therapy, and DMT are incorporated into the nine method components designed to enrich the dance/movement process for young children. This method addresses the intentional use of the sound environment, sound-producing props, and the therapist’s voice as well as techniques for eliciting and responding to clients’ voices. Brief case vignettes demonstrate the potential for this method’s application in clinical settings to facilitate the creation of space for the expressive use of voice.M.A., Dance/Movement Therapy and Counseling -- Drexel University, 201
Project Step: Dismantling Components of Financial Incentive Programs for Physical Activity
No full textInterventions to promote activity observe limited and short-lived success. Financial incentives may provide a short-term reward for physical activity, increasing the likelihood of engaging in activity behavior. However, studies of financial incentives have not evaluated other treatment components that may be important independent of or in concert with incentives. Feedback may increase an individual’s awareness of a goal and salience of an incentive. Study 1 sought to evaluate whether the effect of an incentive for physical activity was larger when providing ongoing feedback compared to having no feedback using a within-subjects design. All participants (n = 24) had a goal of 10,000 steps/day for the duration of the 16-week study. No significant differences were observed, although effect sizes suggest that there was an increase in activity during the incentive-only condition. Presentation order moderated results, such that individuals exposed to incentives with feedback first, compared to those presented with incentives-only first, performed more poorly across both incentive conditions. Additionally, individuals dropped out at higher-than-anticipated rates, were difficult to enroll, and had difficulty reaching the goal. In Study 2, we sought to evaluate the independent and interactive effects of daily vs. weekly feedback and contingent vs. non-contingent incentives in a 2x2 factorial design where participants (n = 61) received personalized step goals each week. Results indicated that daily feedback increased step counts more than weekly, and that contingent incentives increased moderate-to-vigorous physical activity (MVPA) more than non-contingent. Small non-significant interaction effects were observed. Taken together, results of these studies indicate that feedback may be beneficial or iatrogenic depending on how the feedback is perceived (i.e., negatively, if a high goal is unlikely to be reached, or positively, if a goal is perceived as doable). Results suggest that feedback could be leveraged to improve response to incentive interventions.Ph.D., Psychology -- Drexel University, 201
Phase Content Influence on Fracture Properties of Group VB Transition Metal Carbides
No full textTantalum and other group VB transition metal carbides comprise of a class of ultra-high temperature ceramics (UHTCs) that are of particular use in machining tools and fuel-cladding on nuclear reactors. These material microstructures are controlled by the co-precipitation of metal-rich carbide phases, which in turn vary the mechanical properties based on the phase content. The major consideration in the use of UHTCs is their inherent brittleness, and currently little is known about their mechanical behavior in regards to varying microstructures and phase content, especially in niobium carbides. This thesis explores the flexural and fracture properties of two types of group VB transition metal UHTCs: tantalum carbide of carbon/tantalum (C/Ta) ratio in 0.5, 0.75 and 1.0, and niobium carbide of carbon/niobium (C/Nb) composition of 0.5, 0.67, 0.75 and 1.0. It is hypothesized that because of the carbon ratio, a second acicular shape phase will precipitate and ultimately increase the fracture toughness of the material. To explore the validity of the proposed hypothesis, x-ray diffraction (XRD) and scanning electron microscopy (SEM) are used to identify the phase content and microstructure of the carbides, followed by three-point bend experiments using the surface crack in flexure (SCF) method on a universal load frame to determine the fracture properties. Various pre-cracking methods were explored which have been shown to influence the overall fracture toughness, and will be discussed. In addition, digital image correlation (DIC), a full-field identification technique, was used to examine in-situ deformations and resulting strains during loading. Overall, precipitation of metal-rich, acicular-shaped phase demonstrates a strong effect on the carbide fracture properties, and microstructural mechanisms responsible for various phase contents are discussed.M.S., Mechanical Engineering and Mechanics -- Drexel University, 201
The Role of Homogeneous and Heterogeneous Toughening Mechanisms on DGEBA Fracture
No full textAs composite materials become increasingly utilized in engineering applications, it is imperative to understand the role composition has on their fracture and failure behavior. Epoxies, a group of thermosetting polymers, are commonly used in composites as a polymeric binding or matrix material due to their chemical stability and relative material strength. At the same time, their rate-dependent behavior is comparatively unexplored. Moreover, the mechanical properties of all polymers are highly dependent on their chemical makeup, including crosslinking and polymer chain organization. Consequently, this study investigates homogeneous and heterogeneous toughening mechanisms on variants of the epoxy DGEBA under quasi-static and dynamic fracture. Heterogeneous toughening mechanisms were explored via the addition of glass inclusions at three volumes: 5, 15, and 30 percent. Inclusions 7-10 μm in diameter were investigated as this size modifies the polymer structure via crosslinking density and chain organization, and inclusions 30-50 μm in diameter were examined as this size can introduce potential crack bridging and crack path obstacles. Homogeneous toughening mechanisms via diamine hardeners were examined in PACM, D230, and D400. PACM and D230 have similar diamine lengths, but vary in rigidity, and D230 and D400 have the same rigidity and structure, but vary in length. In all cases, quasi-static and dynamic fracture experiments using Single Edge Notch Tensile (SENT) specimens were conducted, and x-ray computed tomography (microCT) was used to investigate samples both pre- and post-mortem. Ultra-high-speed (UHS) imaging along with digital image correlation (DIC), a full-field imaging technique that tracks 2D surface kinematics during loading, were employed to extract fracture behavior. Overall, an increase in fracture loading from quasi-static to dynamic decreased the dependency on bead size for heterogeneous toughening mechanisms, but highlighted the effects of clumping in high volume percent samples; meanwhile homogeneous toughening mechanisms appeared to have higher rate dependency in fracture properties of amines with longer chains and lower rigidity.M.S., Mechanical Engineering and Mechanics -- Drexel University, 201
The Use of Customer Relationship Management in Small Arts Organization
No full textThis thesis discusses how small arts organizations use Customer Relationship Management (CRM) systems in their operations and how they incorporate CRM in their overall strategy. Small arts nonprofits have the need to cultivate constituent relationships to increase audience engagement and donations from individual donors. The theoretical framework of the research is based on literature from the following topics including arts marketing, audience engagement and relationship building, CRM database, and fundraising. The research is a multiple-case study. The author gathered data by interviewing staff from both the small arts organizations and CRM providers. Interviewees gave information about the implementation of CRM systems, pains and gains of using CRM systems, their marketing plan, and their constituents’ data management process. As an integrated technology solution for small arts organizations, CRM helps the organization to keep all the constituent information from various touch points in one database. The implementation of a CRM system is closely related to an organization’s growth. Limited by staff capacity and a lack of a systemized plan in relationship building, small arts organizations are not able to provide highly personalized communications to segmented constituencies. In the future, the CRM system market for nonprofit organizations will be more diverse and more comprehensive in data management.M.S., Arts Administration -- Drexel University, 201
Autism Spectrum Disorder and Empathic Comprehension: A Comparative Review of Empathic Behavior and Implications for Dance/Movement Therapy
No full textThose who've been diagnosed with Autism Spectrum Disorder (ASD) have been assumed to lack the capacity to empathize. This includes the ability to recognize, and respond to, cognitive and emotional signals from other people. Analysis of these claims within the literature may identify inaccuracies that perpetuate unfounded stereotypes, and additionally, reveal therapeutic trends that may accurately help clients with ASD. I've collected case-controlled observational studies comparing ASD, clinical, and typical control groups. These resources have been organized by respective type and method of study in order to analyze emergent themes in the literature. Analysis of sources revealed themes of delayed, but not absent, cognitive comprehension in ASD groups. Assessments of emotional comprehension did not trend toward significant differences between ASD and control groups, but showed patterns that were dependent on the size, persistence, and contextual relevance of the emotional display. Dance/Movement Therapy (DMT) based drama therapy can be used to identify the current level of cognitive awareness, and with cooperative engagement between client and clinician, develop socially-contextual interplay, strengthen reciprocal understanding, and translate whole-body expressions into more intimate exchanges between oneself and others.M.A., Dance/Movement Therapy and Counseling -- Drexel University, 201
A Numerical and Experimental Study of Adhesively Bonded Repairs of Aluminum Fuselage Structures Using Aluminum and Composite Patches
No full textMulti-site cracks may occur in aircraft fuselage structures along the riveted joints as the result of fatigue loading. Traditional repair method is done by removing the damage area and then mechanically fastening a piece of new skin to the fuselage. Adhesively bonded repairs have been shown to be superior than the traditional fastened repairs in restoring the strength of fuselage structures and increasing the service life of the aircraft. Adhesively bonded repairs are beneficial in two key aspects: i) they alleviate the stress concentrations at the fastener holes; and ii) they are structurally and aerodynamically more efficient. Bonded repair technology has been used for military applications for more than two decades, but has not been implemented in commercial aircraft because of the lack of: i) confidence in the ability of adhesive bonded repairs to reduce fatigue crack growth; ii) reliable inspection methods to determine bond quality to ensure strength and durability; iii) appropriate tools for the analysis and design of adhesively bonded repair for curved panels when subjected to realistic flight loading conditions. In this dissertation, a numerical and experimental study on the durability and integrity of bonded repairs was conducted. Experimental work was performed at the FAA WJH Technical Center using its Full-Scale Structural Test Evaluation and Research (FASTER) facility on two fuselage panels removed from a retired B727. Test results revealed that properly designed and installed bonded repairs are effective in reducing the crack growth rate while the degradation of repair quality, such as reducing the number of plies, reducing patch stiffness, and the presence of disbonds between the patch and panel, affects their effectiveness in containing crack growth. In addition, a finite element based predictive model was developed to simulate the fatigue crack growth in the aluminum fuselage panel repaired with aluminum and Boron/Epoxy patches. The model uses the global-local finite element approach and is capable of simulating fatigue crack growth in a full-scale curved fuselage panel subjected to realistic flight loading conditions as well as the thermal residual stresses developed during the bonding process. The validated model was used to conduct studies on the effect of several key parameters of the laminate configuration of the patch on the fatigue crack growth behavior.Ph.D., Mechanical Engineering and Mechanics -- Drexel University, 201
The Arts within Juvenile Correctional Institutions and Facilities: Critical Review of the Literature
No full textThe juvenile justice system has gone through a transformation over the past few decades; from children being tried as adults to now focusing on rehabilitating juveniles in lieu of merely charging them with criminal acts. The present capstone will present how the following facilitators; creative art therapists, art therapists and multidisciplinary artists, conducted art interventions and programs that impact juveniles while in detention. The motivation for this capstone and reviewing how facilitators have been working within detention centers was due to an internship at the Delaware County Juvenile Detention Center in Lima, Pennsylvania. The history of the juvenile justice system will be outlined, and the mental health needs will be highlighted with respect to its impact on juveniles in locked or secured facilities. Finally, a critical analysis of articles that studied the arts, art therapy and creative art therapy will be discussed, concluding with a reflection on the influence that the arts and art therapy has on the juvenile population in detention.M.A., Art Therapy and Counseling -- Drexel University, 201