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Wastewater Effluent Transport and Contamination: A Model for Groundwater Contamination in the Central West Bank
No full textTwo and a half billion people worldwide lack access to improved sanitation. Untreated wastewater contaminates surface water and groundwater sources that may be used for drinking water supply. This critical global issue is foundational to health and development. The Palestinian West Bank is one of the most water-stressed regions on earth with widespread, unregulated wastewater discharge from more than half of all homes resulting in 25 to 97.5 mcm/year. Contaminants have been detected in varying quantities in aquifers, streams, and springs throughout the West Bank. This research provides a gross estimate of the volume of wastewater entering water sources in a 1600 sq. km region between Jerusalem and Jericho and identifies possible contamination hotspots where local Palestinian populations are at risk of contamination through direct water use (drinking, washing) or indirect use (agriculture). This problem is approached using a combination of mapping using geographical information systems (GIS) and groundwater modeling with the MODFLOW and MT3DMS computer codes.M.S., Environmental Engineering -- Drexel University, 201
Understanding the Impact of Exercise Images on Psychosocial Predictors of Physical Activity among Women
No full textVisual images of individuals engaged in physical activity (PA; “PA images”) are widely used in public health campaigns and other media, yet little is known about how different aspects of these images, such as the weight status of the person depicted exercising, affect variables associated with PA (e.g., motivation, liking, self-efficacy, intention) and weight-related attitudes among viewers. This study examined the effect of viewing an online PA promotion brochure featuring PA images of women with overweight/obesity (OW/O images) versus without overweight/obesity (lean images) on variables previously associated with PA and anti-fat attitudes. The moderating effect of viewer weight status (BMI < vs. ≥ 25.0 kg/m2), weight loss desire, social comparison tendencies, internalized weight bias, and baseline anti-fat attitudes on outcomes was also examined. Following pilot testing, 561 women who reported performing <150 minutes of moderate-to-vigorous PA/week were recruited online (Mage= 30.8 years; 80% White; 49% with a BMI < 25.0 kg/m2 and 51% with a BMI ≥ 25.0 kg/m2). Participants completed questionnaires assessing sociodemographic characteristics and potential moderators, were randomized (blocked by BMI < or ≥ 25.0 kg/m2) to view a brochure containing ten lean or OW/O PA images for approximately 3.5 minutes, and then completed post-exposure measures of variables previously associated with PA, anti-fat attitudes, social comparisons with the images, mood, body image, and perceived image characteristics. Results revealed that the interaction between viewer weight status and PA image condition on variables previously associated with PA and on anti-fat attitudes was not significant. The main effect of image condition was also not significant for most outcomes. Viewer weight status, on the other hand, significantly predicted several outcomes: participants with a BMI ≥25.0 kg/m2 reported higher rates of interest in additional contact from the researchers, lower PA liking and self-efficacy, more negative mood and body image, and greater post-exposure anti-fat attitudes. Additionally, a greater tendency to respond positively to upward social comparisons (i.e., to those “better off”) and greater endorsement of pre-exposure anti-fat attitudes generally predicted higher levels of variables previously associated with PA; internalized weight bias predicted lower PA liking and self-efficacy (although the strength of the negative relationship between internalized bias and self-efficacy was attenuated in the OW/O image condition); and weight loss desire predicted higher levels of some variables previously associated with PA, particularly among participants not desiring weight loss in the OW/O image condition. Taken together, findings suggest that, while brief exposure to OW/O PA images may not increase levels of variables previously associated with PA, viewing OW/O images also does not negatively impact these variables. Thus, greater use of OW/O images in PA-related media appears warranted. Person-level characteristics, especially one’s own weight status, also appear to influence variables previously associated with PA. Additionally, while ostensibly positive OW/O PA images may be perceived more positively than lean PA images on some dimensions, viewers with overweight/obesity may report increased anti-fat attitudes after viewing any PA image.Ph.D., Psychology -- Drexel University, 201
Impact of Please ASK on ESL Student Comprehension of the English Article System Before Proper Nouns: A Phenomenological Study
No full textAs English language grew as a primary means of communication, pedagogical approaches have emerged to meet this need. Communicative Language Teaching (CLT) has fulfilled this need. English grammar has been universally accepted in the field of pedagogy as essential for communication in the language, albeit, debate still exists regarding the degree to which grammar should be expressly taught. The CLT approach expressly acknowledges the need for grammar to promote fluency in learners; however, a conundrum exists. Some grammar in the language seemingly adheres to a logical framework, and thus can be explained easily. On the other hand, other grammar facets prove difficult or impossible to clearly explain via traditional means. One such facet is mental grammar. A salient illustration of mental grammar in English involves when to use the definite and null (the absence of) articles in front of proper nouns. Current literature in the field yields no viable explanation for learners beyond simple guesswork and memorization. As such, research in the field has explicitly called for a need to clearly explain this grammar convention. To address this problem, the researcher used creative efforts to foster a solution. The result was a researcher-developed heuristic. This heuristic offers an alternative explanation for the use of articles before proper nouns, which appears to abate the difficulties in learner comprehension of this grammar point. The heuristic itself represents a mnemonic device containing letters denoting proper noun categories. These specific categories denote when no articles before proper nouns are used. This phenomenological study sought to capture student participants' lived experiences while engaging with the Please ASK heuristic, as developed by the researcher, as they attempted to make sense of the English language article system before proper nouns. Interviews and focus groups were used to ultimately find emergent themes and the essence that could describe what the participants saw and felt as they employed Please ASK--a buffer between proper noun article grammar and student comprehension of that grammar. In this way, Husserlian Transcendentalism played a key role in this study. The study results supported student participants' perception of Please ASK as a viable means to understanding the obscure proper noun article grammar. Participants noted a change in understanding of the grammar and perceived increases in confidence in using English.Ed.D., Educational Leadership and Management -- Drexel University, 201
The Role of Chtf18 in Sister Chromatid Cohesion and Post-Replicative Genome Maintenance
No full textMitosis is a critical process that all living cells undergo to produce two identical daughter cells. To ensure that each daughter cell contains the same requisite genetic material, cohesion must be established and maintained between sister chromatids. Chromosome Transmission Fidelity factor 18 (CTF18), a protein subunit of the Replication Factor C-like complex (CTF18-RLC), has functions in DNA replication and also helps to establish cohesion between sister chromatids in yeast. Previously, we demonstrated a function for CHTF18 (the mouse ortholog) in meiotic recombination that is consistent with a role in chromosome cohesion during mammalian meiosis. We used Chtf18−/− and wild type murine embryonic fibroblasts (MEFs) to investigate a possible function for CHTF18 in sister chromatid cohesion and post-replicative genome maintenance. Cultured Chtf18−/− MEFs ceased proliferating after the 6th population doubling compared to wild type MEFs, which continued to proliferate until the 11th doubling. Immunofluorescence staining with 53BP1 antibody, a marker of DNA double strand breaks (DSBs) showed that DSBs are increased in Chtf18−/− MEFs. These findings suggest that defects in cellular proliferation of Chtf18−/− MEFs are due to DNA damage. Analysis of chromosome spreads reveals that Chtf18−/− MEFs may have a propensity for increased sister chromatid separation and breakage. Together, our data indicate a role for CHTF18 in sister chromatid cohesion and post-replicative genome maintenance.M.S., Biochemistry -- Drexel University, 201
Art Galleries at the Jersey Shore: Sustaining an Arts Business in a Seasonal Shore Town
No full textGalleries located in coastal regions in New Jersey are exposed to conditions that force the businesses to adopt tactics and strategies to sustain their business models. This is due to factors such as rise and fall in business, changes in customer demographics by season, and finding a variety of methods to generate revenue in a condensed time period. Eight gallery owners or managers in the coastal towns of Cape May, Atlantic City, Tuckerton, and Surf City were interviewed through a series of research questions. Interviews covered topics such as business strategies, programming choices, staffing capacity, their personal choice to work multiple jobs or only run their gallery, social media usage, and other unique solutions their gallery has utilized. There was a great variation in methods of adaptation utilized by each business to cope with the seasonal nature of its location and fluctuating customer bases. Business strategies were not dependent on location, rather there was a loose correlation between age of gallery and strategies. Most gallery owners and managers interviewed had at least one additional occupation or business. Motivations to work multiple occupations were dependent on the owner or manager rather than the town or their corresponding gallery’s operational calendar. Staffing for each gallery varied, especially with a distinction between seasonal and year-round employment. Choices of themes, disciplines, and aesthetics for each gallery had a variation in connection to imagery of the town’s local iconography and culture. The most common theme and images for works for sale were ocean-related icons and a focus on artists from the region. Strategies incorporating technology, such as social media or websites, were used at every gallery which exposed a variation in each gallery’s methods for trying to capture customers and processing sales. Businesses who utilized technology more frequently, with variation in applications and methods, were able to capture more customers beyond the area’s peak season. The galleries studied are connected because they experience seasonality as a business in a coastal town, but their solutions are truly unique to their brand identity. The creative solutions discussed in this paper can serve as a starting point for other businesses to apply and adapt to their own business models.M.S., Arts Administration -- Drexel University, 201
How Chinese Production Companies Produce Adapted Broadway Musicals
No full textIn recent years, the Chinese musical industry has been developing rapidly since the Broadway musical Les Misérables began its tour through China in 2002. Local production companies have imported musicals’ copyrights and produced the Chinese version of works while using local cast and language, although the market performance of those adapted works was not guaranteed. This thesis aims to find out what Chinese local production companies are doing in order to create a successful show. Seven Ages (Beijing) Culture Investment Co., Ltd. and China Dream Live Entertainment Co., Ltd. (CDE Live) are two Chinese production companies that focus on musicals; they both consist of teams equipped with highly experienced professional producers and experts. In the last several years, these two companies created a series of Chinese versions of musicals from Broadway and the Western world. This thesis explores relevant producing experiences and their current and future needs for development.M.S., Arts Administration -- Drexel University, 201
Observations and Influences of Real-Time Indoor Ammonia Concentrations during HOMEchem
No full textAlthough ammonia (NH3) is usually found at outdoor concentrations of 1-5 ppb, indoor ammonia concentrations can be much higher. Indoor ammonia is strongly emitted from cleaning products, tobacco smoke, building materials, and humans. Because of ammonia's high reactivity, solubility in water, and tendency to sorb to a variety of surfaces, it is difficult to measure, and thus a comprehensive evaluation of indoor ammonia concentrations remains an understudied topic. During HOMEChem, a comprehensive indoor chemistry study which occurred in a test house in June 2018, the real-time concentration of ammonia indoors was measured using cavity ring-down spectroscopy. A mean unoccupied background concentration of 32 ppb was observed, with further enhancements of ammonia occurring during cooking, cleaning, and occupancy activities, reaching maximum concentrations during these activities of 130 ppb, 1592 ppb and 99 ppb, respectively. Furthermore, ammonia concentrations were strongly influenced by indoor temperatures and heating, ventilation, and air conditioning (HVAC) operation. In the absence of activity-based sources, the HVAC operation was the main modulator of ammonia concentration indoors.M.S., Environmental Engineering -- Drexel University, 201
A Phenomenological Study: Exploring Female Superintendents' Lived Experiences to Understand Factors Related to Their Superintendency Career Paths in Pennsylvania
No full textThis research explored lived experiences of female superintendents to understand factors that supported or created barriers for women in their career advancement while becoming a superintendent. A phenomenological study design framework was applied to the research to explore the journey women faced including the successes, struggles, and level of support they experienced during their career paths. Background research examined leadership roles, which address gender bias, ratio of female to male principals and superintendents, and other gender specific issues. In this study, seven female superintendents in the state of Pennsylvania were interviewed using a semi-structured one-on-one interview process. From the data, four themes emerged including, (a) Challenges They Faced, (b) Finding Balance, (c) Supporting Factors, and (d) Positive Attributes of the Job . A few recommendations to help increase the number of females in leadership positions include the concept of networking with other females for support purposes and to create a mentoring program that could be implemented by any school district nationwide.Ed.D., Educational Leadership and Management -- Drexel University, 201
Topology Preserving Nonlinear Image Registration
No full textImage Registration is an algorithmic optimization process primarily aimed at estimating the most optimal transformation from one image's coordinate plane onto another. Nonlinear image registration has been the subject of numerous research initiatives. This widespread focus on the topic has resulted in a variety of different registration methods, intrinsic novel findings, as well as application areas. Although many potential use cases exist, the main three typical applications for 2D and 3D registration methods include object tracking in a series of scans, interpatient registrations, and multi-modal registration. Substantial research efforts have also begun to observe the registration process in both constrained and unconstrained settings as well as applied focused work on the regularization and homeomorphic behavior of vector fields for more accurate registration results. In this thesis, we compare the registration accuracy of our log unbiased multi-resolution registration model against the model provided by Igor et al. [16]. We also compare the effects of various objective functions on the ultimate accuracy of our multiresolution registration framework. Additionally, we delineate the short-comings of the log unbiased model [16] and mathematically propose a method to further accommodate these shortcomings as well further enforce topology preservation and smoothness in the displacement fields in hopes of making the model more robust specifically in a continuous setting. Our multi-resolution method utilizes information theory to quantify the magnitude of deformations, generates intuitively correct deformation maps, and correctly represents non-smooth transformations. To demonstrate the efficacy of the proposed framework, we generalize the well known large-deformation viscous fluid model. We are able to show that our proposed multi-resolution scheme generates more accurate transformation maps compared to those generated using the plain viscous fluid model with fluid regularization. We examine the power of this model to detect real changes specifically as we compare its use with different matching functionals. The results presented in this work show that the unbiased methods have higher reproducibility and accuracy than conventional registration models. Numerical results are presented in chapter 4, 5, and 6.M.S., Computer Engineering -- Drexel University, 201
Development of an Improved Fabrication Method for an Ultrasound-Sensitive Platform for Drug Delivery to Hypoxic Tumor Sites
No full textThe efficacy of cancer treatments such as chemotherapy and radiation therapy can be limited by the presence of hypoxic regions within the tumor, leading to poor clinical outcomes. Our group has developed SE61O2¬, a microbubble comprised of a Span 60 (sorbitan monostearate) and water-soluble vitamin E (TPGS) shell with an oxygen gas core, for delivery of oxygen to hypoxic tumor sites. In vivo studies have shown that mice receiving SE61O2 with ultrasound followed by radiation have decreased tumor growth and increased survival, suggesting the potential of SE61O2 to sensitize tumors to radiation therapy. However, the duration of oxygenation after administration of SE61O2 does not last long enough for it to be clinically viable. To increase the duration of oxygenation, our group is investigating lonidamine-loaded SE61O2 (SE61O2-LND), to capitalize on the fact that lonidamine targets tumor metabolism and has been shown to increase sensitivity to radiation therapy. The current fabrication method for SE61O2-LND required the use of methanol and resulted in low drug loading that had high inter-batch variability, leading to a need for an improved methodology. The purpose of this study was to develop an improved fabrication method of SE61¬O2 MBs for drug loading applications. The requirements for drug loaded microbubbles fabricated with the improved methodology are that they needed to meet the minimum acoustic requirements (enhancement ≥ 15 dB and half-life ≥ 1.5 min), have a diameter < 6 µm, be able to support an oxygen gas core, and meet the minimum drug loading requirement of 2 µg/mL. Since TPGS, one of the shell-forming molecules, forms micelles at a low critical micelle concentration, it was hypothesized that we could use these micelles to solubilize lonidamine, as it is a hydrophobic drug, and capitalize on the fact that the concentration of TPGS used to fabricate SE61 is greater than the critical micelle concentration of TPGS. The design resulted in MBs that had acoustic and size properties that met the requirements and that were not significantly different from those made with the standard method. Furthermore, it was found that the TPGS micelle method greatly improved the yield and produced twice as many microbubbles. Initially, it was believed that this may be due to the different fabrication methods resulting in microbubbles with different shell compositions; however, NMR studies showed that the molar ratios of the two surfactants were similar in microbubbles made by either method. Next, Nile red was used as a model hydrophobic drug to assess the loading capabilities of both methods. Drug loading did not affect the acoustic or size properties of the microbubbles for either method. Both methods exceeded the minimum drug loading requirement, but microbubbles made with the TPGS micelle method had loaded twice as much Nile red per batch as the standard method. This could be attributed to the increased microbubble yield attained with the TPGS micelle method. The improved methodology was then applied to lonidamine loading. While the resulting microbubbles met all the necessary requirements, lonidamine loading was lower than expected for the TPGS micelle method based on the Nile red results. This suggests that lonidamine may not intercalate into the TPGS micelles or SE61 microbubble shell the same way Nile red does. Further studies must be completed to characterize lonidamine loading and explore alternative methods for formation of drug loaded micelles.M.S., Biomedical Engineering -- Drexel University, 201