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Structural Characterization of the lncRNA WSPAR
No full textLong non-coding RNAs (lncRNAs) are RNA molecules of at least 200 nucleotides in length with no protein coding potential. While there is growing information about how lncRNAs function in a variety of biological processes, little structural information is known about these molecules. The first step of forming a structure-function relationship for RNA is the development of a secondary structure model. Such information about secondary structure is gathered via chemical structure probing and in silico folding. However, few secondary structures for lncRNAs have been published. Herein, we report a secondary structure model for the lncRNA WSPAR (Wnt Signaling Pathway Activating RNA), generated via SHAPE (Selective 2' Hydroxyl Acylation analyzed by Primer Extension) probing and validated with DMS. This model allowed us to identify structural elements which are highly conserved across mammals. These findings indicate a functional importance for these elements of WSPAR in its role of upregulating wnt signaling in the context of several cancers.M.S., Biochemistry -- Drexel University, 201
The Nature of University-Led Technological, Pedagogical, and Content Knowledge (TPACK) Professional Development: A Multi-Perspective Phenomenological Study
No full textThe use of technology has become customary for many faculty teaching in institutions of higher education. And, many institutions provide professional development (PD) for integrating instructional technology into the classroom. But, research shows that many PD opportunities emphasize the use of specific technology tools and are inefficient at teaching faculty how to approach technology integration that is particular to their discipline. The objective of this study was to explore instructional technology administrators' lived experiences creating technology-integration profession development opportunities for education faculty and education faculty's experiences participating in these opportunities. The rationale for this study emanates from the researcher's aspiration to create PD opportunities for education faculty that enhance the effectiveness of their teaching. This study utilized a qualitative transcendental phenomenological methodology to explore the lived experiences of instructional technology administrators and education faculty. The central question to guide this study was the following: Using the Technological, Pedagogical, and Content Knowledge (TPACK) framework, what are instructional technology administrators' lived experiences on creating technology-integration professional development opportunities for education faculty, and what are education faculty's lived experiences engaging in technology-integration professional development? Purposeful and snowball sampling methods were used for selecting three instructional technology administrators and eight education faculty. The primary data collection method was an in-depth interview; supportive methods included non-participant observations and document analysis. The data were coded through initial and focused coding. Through analysis and interpretation, data were organized into themes that emerged in the data. This study revealed many experiences associated with creating and engaging in technology-integration PD. These experiences showed that PD is created for large audiences and covers broad topics; however, education faculty are interested in support for a specific task. TPACK professional development is infrequent. However, based on the one-to-one nature of support that is often given to education faculty, there is potential to offer TPACK PD in alternative settings outside of the traditional large-group environments. Recommendations are offered for instructional technology administrators, university leaders, and further research opportunities. Given the various resources available in each instructional technology department, the recommendations put forth should be considered for its appropriateness on an individual university basis.Ed.D., Educational Leadership and Management -- Drexel University, 201
Vocational Multitasking Ability in TBI: Is Sleep a Contributing Factor?
No full textA non-trivial subset of individuals with TBI report cognitive deficits and difficulty with vocational functioning that persist for many years post-injury. Prior domain-specific approaches to measuring the relationship between cognitive deficits and vocational functioning in traumatic brain injury (TBI) have yielded mixed results. Therefore, current research must consider a more complex cognitive construct that integrates multiple cognitive domains, such as multitasking. Qualitative reports suggest that multitasking difficulty may impact vocational functioning after TBI. Experimentally assessing multitasking ability requires a performance-based assessment that approximates naturalistic environments. To date, one such assessment, the vocational multitasking test (VMT) has been developed and tested with multiple sclerosis (MS). This performance-based assessment has not yet been examined with TBI. Thus, the main aim of this study is to examine the VMT with a previously untested clinical population of TBI. Cognitive deficits in TBI may also be compounded by sleep disturbance, which is exceedingly common after TBI. In individuals with TBI, sleep disturbance impacts the cognitive domains that underpin multitasking, including memory, executive functioning, and attention. There is some research to suggest that sleep disturbance may also impact vocational functioning after TBI. However, this link has not yet been extensively studied. The current study consisted of three specific aims: 1) evaluate the psychometric properties of the VMT in a previously untested clinical population, 2) examine VMT performance in TBI compared to healthy controls (HC), and evaluate its relationship to vocational functioning, and 3) examine sleep disturbance and its relationship to VMT performance in TBI. In a sample of 5 individuals with TBI, 3 had sustained a mild TBI (mTBI) and 2 had sustained a severe TBI. VMT performance was related to measures of immediate and delayed verbal memory, problem solving, inhibition and switching, and processing speed in the TBI sample. Participants with mTBI and postconcussive symptoms (PCS) had difficulty returning to work (RTW), without measured cognitive impairment, while participants with severe TBI had cognitive impairment and difficulty with RTW. However, VMT performance was not related to vocational functioning in the TBI group. Individuals with TBI endorsed poorer sleep quality and marginally greater insomnia severity compared to the HC group, with no difference in sleepiness. Sleep variables were not related to VMT performance. Conclusions from the current study are limited by the small and unequal sample sizes. However, results indicate that RTW remains a challenge after TBI across the severity spectrum, and the VMT is a feasible task for these participants to complete. Results continue to support Morse’s (2014) findings that VMT performance requires cognitive domains that underpin multitasking ability. If future studies demonstrate that VMT performance is related to vocational functioning, the VMT could be used as a rehabilitation tool for TBI.M.S., Psychology -- Drexel University, 201
A Study of the Final Deposition of Inkjet-Printed Complex Bioink Drops
No full textRegenerative medicine has been gaining a great deal of popularity in the recent years due to the advent of technology that allows for the fabrication of lost tissues and organs in the human body. A process that enables this fabrication is called bioprinting, which uses additive manufacturing methods such as inkjet printing to create 3D cellular scaffolds out of polymer-based bioinks. In recent years, 4D bioprinting was introduced where the inkjet-printed 3D structure evolves over time and self-folds into a desired shape upon the application of a stimulus. One of the parameters that influences the folding is the deposition morphology of the 3D structure. However, the underlying physics of the deposition morphology of bioinks still remains elusive. In this study, the effect of substrate temperature and drop size on the final deposition morphology of an inkjet-printed bioink droplet were investigated. Substrate temperature was varied between 22°C and 80°C, and drop size was varied from 200pL to 65nL. Increasing substrate temperature resulted in the formation of a coffee-ring deposition and increasing drop size led to the formation of a volcano-like deposition. The thermal and surfactant Marangoni numbers for each case were calculated and were found to be independent of the substrate temperature. Furthermore, the surfactant Marangoni was found to be the dominant flow among the various Marangoni flows in all the cases studied here. Thus, with increasing substrate temperature, the strength of the Marangoni flows stays constant while the evaporation-driven flow to the contact line intensifies, resulting in a coffee-ring deposition. With increasing drop size, the Marangoni flows are strengthened (i.e. the Marangoni number increases), which should theoretically result in a uniform deposition rather than the volcano-like deposition observed. This unexpected result may be caused by polymer gelation during evaporation, as also recently indicated by others. Nevertheless, more work needs to be done to understand the details behind how the various components of the bioink govern the deposition dynamics and morphology.M.S., Mechanical Engineering and Mechanics -- Drexel University, 201
Co-product utilization: Environmentally friendly methods for recovery of high-value products from orange peel
No full textOrange processing generates waste streams including peels and pulps. Orange peels can be utilized for the recovery of high-value products such as limonene, soluble sugars, and dietary fiber. However, organic or hazardous solvents are typically used for the extraction of such components. Further, no work has reported simultaneous extraction of different bioactive components aiming at complete utilization of a co-product. The aim of this study was to evaluate different environmentally friendly methods for simultaneous extraction of oil, soluble sugars, and dietary fiber from orange peels. Enzyme-assisted aqueous extraction (cellulase) and ethanol extraction (95% v/v) methods were evaluated. After extraction, oil was recovered and analyzed for limonene, liquid fraction was analyzed for sugars, and solid fraction was analyzed for soluble and insoluble dietary fiber. Further, in enzyme-assisted oil extraction, different cellulase concentrations (0, 0.4, 0.85, or 2% of dried solids) and incubation times (1, 3, 5, or 14.5 h) were tested. There was no significant difference between oil yields from cellulase treatments by 0.85% cellulase concentration in acetate buffer for 1, 3, 5, and 14.5 h from two replications, and by 2% cellulase concentration in DI water for 1,3, and 5 h from a single replication. With 2% enzyme concentration, higher limonene contents were recovered for 1h treatment compared to longer treatment times. There was no significant different between aqueous and acetate buffer solution on the oil yield from orange peels with 0.85% enzyme treatment for 1h. Highest oil yield, 12.23±3.79 % for fresh samples and 9.28±10.51% for dried powders, was achieved by 2% cellulase concentration with 1 h incubation, however, highest limonene content, 306.40±24.19 [mu]-g/ml for fresh samples and 195.97±19.22 µg/ml for dried powders, was recovered by 0.4% cellulase concentration with 1h incubation. For ethanol oil extraction, higher limonene content, 714.54±94.36 µg/ml, can be obtained from fresh samples compared to dried powders, 96.08±4.73 [mu]-g/ml. Higher limonene contain from fresh samples can be obtained by ethanol extraction, 714.54±94.36 [mu]-g/ml, compared to 0.4% enzyme extraction, 306.40±24.19 [mu]-g/ml. Lower IDF% can be observed after enzyme-assisted extraction compared to water extraction (control). Solid fractions after ethanol extraction contained higher IDF%, 56.09±8.62 % for fresh samples and 57.29±1.37 % for dried powders, compared to enzyme-assisted extraction or water extraction (control). Higher SDFP% were obtained most after 0.4% enzyme-assisted extraction in dried powders, 24.94±0.92 %, and after 95% ethanol extraction in fresh samples, 24.30±2.57 %. These results indicate that both enzyme-assisted aqueous method and ethanol extraction could be used for recovery of functional components from orange peel, simultaneous recovery of various products and oil recovery will be better observed with suitable enzyme concentration. The fermented sugars can be obtained more in the liquid fraction of dried powders than fresh peels. For enzyme assisted extraction, the higher sucrose and glucose contents, 4.07±0.79 mg/mL and 9.82±1.88 mg/mL, was observed after 2% cellulase treatment, and the highest fructose content was observed with water treatment (control), 9.22±1.60 mg/mL from powdered orange peels. The highest glucose content, 10.86±4.38 mg/mL, was achieved after 95% ethanol extraction from powdered orange peels. To conclude, 95% ethanol extraction can extract higher limonene, IDF, and SDFP, but lower fermented sugars compared to 0.4% enzyme-assisted extraction in fresh orange peels.M.S., Food Science -- Drexel University, 201
Online Analysis and Control of Electric Power Distribution Systems
No full textHistorically, electric power distribution systems were considered passive subsystems served by the larger transmission grid. Recently, smart grid initiatives have driven the evolution of distribution systems into active systems with market-aware customers and distributed power generation. Along with more diverse and complex injections, contemporary distribution systems are equipped with additional sensing equipment, two-way communications networks, and advanced metering infrastructure (AMI). These are essential technologies that enable several core functions of a smart grid, including real-time monitoring and online control. This thesis presents several tools for the online analysis and control of modern electric power distribution systems. "Online" refers to a control framework that can react to changing system conditions in order to maintain static security and meet different operating objectives. Specifically, the objective of this research is to integrate temporal information (i.e., forecasts) into distribution system analysis tools while maintaining fundamental engineering requirements by re-examining classical problems through a contemporary lens. Connected by an underlying injection forecast model, three research topics are explored: 1) distribution load capability, 2) analytical time window selection for quasi-static time series (QSTS) analysis, and 3) distribution state estimation with explicit consideration of non-synchronized measurements. The work proposed here is a necessary step towards distribution system optimization in an online setting with uncertain and/or bidirectional power flows.Ph.D., Electrical Engineering -- Drexel University, 201
"Time of the Month": A mixed-method study to understand and improve Menstrual Health and Hygiene Management in Rural North India
No full textBackground: Menstruation is a naturally occurring monthly phenomena which affects adolescent girls and women worldwide. The last decade has highlighted how menstrual hygiene management (MHM) is a public health issue because of its link to health, social justice and human rights. Menstruation is considered a taboo topic, related to uncleanliness and impurity around the world. Menstruation related restrictions have shown to increase poor hygiene behaviors, nutritional deficiencies, gender inequality, marginalization and isolation. A Social and Behavioral Change Communication (SBCC) intervention called GARIMA was implemented in three districts of Uttar Pradesh, India to improve adequate menstrual behaviors. Therefore, the overarching question of this dissertation asked: Is SBCC an effective approach to improve adequate menstrual behaviors among adolescent girls in rural North India? To answer the overarching question, three research questions were asked: 1) what are the psychometric properties of a menstrual hygiene management scale? 2) What is the relationship between menstrual related restrictions and menstrual health and hygiene management (MHHM)? 3) How does a social and behavioral change communication intervention predict MHHM? Methods: A mixed method approach was used to analyze the overarching question. Interviewer-administered structured questionnaires were completed on tablets to understand MHHM among 2212 adolescent girls in three districts of Uttar Pradesh, India. A total of 36 Focus Group Discussions were conducted with 309 adolescent girls in the three districts. Villages and adolescent girls were matched on socio-demographic and socio-economic characteristics in the intervention and comparison sites. Results: MHHM is a multi-dimensional construct comprising of behaviors which are time bound to menstruation (menstrual health) and behaviors which not time bound to menstruation (hygiene management). Drawing from existing conceptual definitions and their operationalization in this research the author defines MHHM as “Access and use of private toilet/bathroom with soap and water to wash hands and have a bath during menstruation and use of clean menstrual management material to absorb or collect blood that is stored in a safe, clean place and changed at least three times a day for the duration of the menstruation period, and accessing facilities to ultimately dispose of used menstrual management materials”. Overall, 27.58% of the adolescent girls practiced all adequate MHHM behaviors. Ninety six percent of adolescent girls stated they faced restrictions during menstruation. In general, not having restrictions had a positive relationship with adequate MHHM behaviors. The results from the evaluation showed that higher encoded exposure (dose and recall of the program) had a direct relationship with adequate MHHM. The evaluation also showed that indirectly, higher encoded exposure predicted higher knowledge about puberty, higher knowledge about reproductive parts, positive attitudes towards gender, better interpersonal communication, and thereafter, adequate MHHM. Conclusions: MHHM is a public health issue which cross-cuts through several sustainable development goals. Findings demonstrated that MHM is a multi-dimensional construct with four independent indicators corresponding to menstrual health (preparation of clean absorbent, storage of clean absorbent, frequency of changing and disposal) and one indicator corresponding to hygiene management. Therefore, the author recommends future research should use the acronym, MHHM. Restrictions were ubiquitous and mostly had a negative relationship with adequate preparation of clean absorbent, adequate storage of clean absorbent, adequate frequency of changing and disposal. A SBCC program directly improved MHHM and indirectly improved knowledge, some attitudes, interpersonal communication and therefore, adequate MHHM. These findings can be used in developing future programs and strengthening future research on MHHM.Dr.P.H., Community Health and Prevention -- Drexel University, 201
Principals' Perceptions of Changing the Age=Grade Traditional Model of Schooling
Get PDFThe traditional education system has roots in the colonial and industrial eras, but the purpose of education in today's dynamic and global economy has vastly changed. Schools need to produce creative thinkers and problem solvers. This research reviewed existing literature to explore the intersections of multiage learning, mastery learning, and blended learning in elementary schools. Centered on research questions that examined principals' perceptions of moving to a new model of elementary schooling that breaks down the barriers of age = grade (students placed into classroom because of their age) traditional schooling, this study sought to support the implementation of instructional strategies to meet elementary students' needs in the digital age. A phenomenological qualitative research design was used for the study. Six elementary school principals in schools that have implemented some aspects of multiage learning, mastery learning, and blended learning were interviewed to construct a description of their experience of breaking down the barriers of age = grade traditional elementary schooling. The findings showed that teacher capacity, progression of the curriculum, technology, time/master scheduling, and principal/teacher readiness for change emerged as barriers to moving to a new model of elementary schooling. Many conclusions were revealed in the data, but perhaps the most important was that barriers to changing the age = grade model of elementary schooling are not insurmountable. This study showed that there is a willingness and eagerness to make changes to the traditional age = grade elementary school model to meet the needs of students in the digital age.Ed.D., Educational Leadership and Management -- Drexel University, 201
Success within an Unlikely Candidate: A Phenomenological Study of the Lived Experiences of Academically Successful Youth who have Aged out of Foster Care
No full textFor many of America's youth, completing high school and moving forward with post-secondary education is a natural path for successful living. Unfortunately, many youth in foster care experience a variety of challenges that prevent them from completing high school, entering and/or completing post-secondary education, and leading successful independent lives. This phenomenological study explored the essence of the lived experiences of youth who have aged out of foster care and have succeeded academically. The phenomenological approach allows the voices of the youth who have aged out of foster care to be heard. This study followed three streams: lived experiences, social support, and transitional support collaboratively leading youth who have aged out of foster care to academic success. In an effort to understand the experience through the eyes of those most directly affected and represented by the foster care system, phenomenology, a philosophical method that studies the pure science of a phenomenon, was the chosen methodology. Allowing youth who have aged out of foster care the opportunity to share their experiences as they recall them offers a pure account of their experiences as they happened without any bias or prejudice displayed. Primary findings of this research were that those who spend time within the foster care system are a part of a stand-alone community governed by its own set of rules, standards, and values; relationships with others played a vital role in their academic success; internal and external motivators were necessary for completing high school and moving forward with post-secondary education, and the realization that it takes a village to raise a child, shows the value in the communal effort for taking special care of this population of youth. As a result of these findings, recommendations were made. There are recommendations for social services and lawmakers to level the playing field so that all youth in foster care will have access to the same standard of care; provide and market more realistic support from post-secondary programs and schools; standardize group home academic programs, and increase in-home visits to ensure that every child's basic needs are met within the foster care system.Ed.D., Education -- Drexel University, 201
Understanding the Most Frequently Experienced Barriers to the Adherence of Lymphoma Clinical Practice Guidelines (CPGs) and Their Effect on the Lymphoma Physicians' Utilization of CPGs: An Explanatory Mixed-Methods Study
No full textClinical practice guidelines (CPGs) have been developed for almost all tumor types including lymphoma by medical and professional organizations. The CPGs have been developed to control the variability in clinical practice. When followed completely, these evidence-based practices are meant to provide an equal quality of treatment to all oncology patients. However, structural, behavioral, and environmental barriers to the adherence of lymphoma CPGs exist. The purpose of this sequential explanatory mixed methods study is to measure the most frequently experienced barriers to the adherence of lymphoma CPGs and explore how these barriers affect lymphoma physicians in the utilization of CPGs. The results revealed that among predictors such as the total score from each of three domains of barriers studied, sex, age group, region of practice, location of medical practice, and duration of medical practice examined, the social/environmental domain of barriers was statistically associated with the use of lymphoma CPGs (p=0.0089). The higher the score, the more likely is to implement lymphoma CPGs, whereas in the professional attitudes domain, the higher the score the less likely is to implement lymphoma CPGs such as the NCCN CPGs (p=0.0071). No association was found in the organizational domain of barriers. Additionally, statistically influential covariates in following lymphoma CPGs were observed in each of three domains of barriers. They are location of medical practice, advanced age, and geographical regions such as the South. While lymphoma doctors liked and found lymphoma CPGs to be evidence based they want to have more data known and published on how the adherence of lymphoma CPGs translates to positive patient outcomes and a decrease in healthcare costs. Subsequently, lymphoma doctors' expectations are to be able to make warranted exceptions when patients' comorbidities and variability exist without being called noncompliant. Technology should be reactive, proactive, and be utilized more efficiently in the implementation of CPGs and clinical pathways. Likewise, lymphoma doctors believe insurance plans need to change to provide uniformly a much better coverage for lymphoma patients' variability, drug tolerability, and lower-deductible costs in United States.Ed.D., Education -- Drexel University, 201