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An Investigation into Methods for Electrospinning Poly(ether ether ketone).
No full textElectrospinning is a well-established method for forming polymers into micron and sub-micron size fibers. During electrospinning a polymer in a liquid state, either in solution or molten, is drawn into a fibrous shape using applied high voltage. This thesis sets out to show a new method for electrospinning Poly(ether ether ketone) (PEEK). PEEK has thermal, chemical, and mechanical properties that make it desirable for many applications in filtration and textiles. However, these desirable properties also make PEEK a difficult material to process. It is insoluble in most common solvents at room temperature, with the exception of Sulfuric Acid at greater than 95% concentration. Yet, PEEK undergoes a reaction known as sulfonation when dissolved in Sulfuric Acid. Sulfonation adversely affects PEEK’s thermal and chemical properties. Therefore, this thesis provides a method for electrospinning PEEK without sulfonation, by electrospinning the polymer in a molten state rather than in solution. By keeping PEEK in its native, unsulfonated state, the resulting fibers are shown to retain their thermal and chemical properties. Furthermore, the fibers are shown to be of micron and sub-micron size. To the best of my knowledge, this thesis presents the first successful method for electrospinning native PEEK fibers
Contemplating Grace: Memories from a Manuscript (Catalogue and Interdisciplinary Study of Tufts University Ms. 2, Hours of the Virgin).
No full textThis senior honors thesis is an interdisciplinary examination of a Late Medieval Book of Hours, which is the first published study and codification of the manuscript. The paper seeks to define the manuscript’s context of production, while examining its bicultural environment, the role images played in Medieval prayer, and the organic nature of the book itself.http://hdl.handle.net/10427/00976
Case Study: Why did the Central Bank of Jordan put Policies for Financial Inclusion in Place?
No full textSubmitted in partial fulfillment of the degree Master of Arts at the Fletcher School of Law and Diplomacy. Abstract: This capstone, case study, explores the ideas and rationale behind the decisions made by the Central Bank of the Hashemite Kingdom of Jordan to incorporate policy structures for financial inclusion, i.e. to include the poor population and refugees in Jordan to use financial services
Functional screening of established and experimental weight loss drugs in terms of their effects on central dopamine release kinetics
No full textAbstract: Obesity is considered to be one of the main and important causes of morbidity, mortality, and limited life quality. There are many reasons and theories explaining the mechanism obesity and one of these theories is the brain Dopaminergic signaling pathway. It has shown that dopamine plays a major role in obesity; it has revealed that obese subjects have limited dopamine receptors which in turn impair brain dopamine circuit and this will lead the obese subject to eat more as a compensatory mechanism to overcome the dopaminergic limitation. However, some anti-obesity medications work on the dopamine pathway and correct this defect. In this study, we examine some medication such as Topiramate and NAAA inhibitor to see if they have any role in reducing weight through the dopaminergic system. We use electrophysiological methods to examine the dopamine release from the brain striatum and compare it with the baseline release. At the end of this study, Topiramate has shown a high reduction in the dopamine release when compared with the baseline release. However, NAAA inhibitor showed the opposite. It has displayed that NAAA inhibitor increase dopamine release comparing with the baseline dopamine release. In conclusion, we are assuming that Topiramate reduces weight through a different mechanism other than increasing dopamine level. In contrast, NAAA inhibitor may show a reduction in weight through a different mechanism as well. Further investigation is needed in order to understand the link between obesity and dopaminergic signaling pathway.Thesis (M.S.)--Tufts University, 2018.Submitted to the Dept. of Pharmacology and Drug Development.Advisor: Emmanuel Pothos.Committee: Efi Kokkotou.Keyword: Nanoscience
School Employee Wellness: Understanding Health Behaviors and Identifying Opportunities for Student and Staff Health Promotion
No full textAbstract: BACKGROUND: Despite the growth of workplace wellness nationwide, schools lag behind other employers in the promotion of employee health and the provision of employee wellness programming. School employees, however, serve as role models for students, and are called upon to deliver student health-related programs, including physical activity (PA) programs. Employee wellness can increase productivity, boost morale, save money, and, in the school setting, potentially enhance student program implementation and academic success. However, evidence suggests poor health among school employees. The primary objectives of this research were to provide evidence to support the need for and value of school employee wellness, particularly in underserved school districts, and to inform employee wellness efforts in the school setting. METHODS: Employees were recruited from lower-income Massachusetts schools participating in the Fueling Learning Through Exercise (FLEX) Study, a group randomized-controlled trial evaluating two school-based PA programs. Focus groups were conducted to identify barriers and facilitators to healthy behaviors. Employees participated in Wellness Assessments, including measured height, weight, and lipids [total (TC), high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C)]. Surveys were used to collect demographic, perceived stress, PA and 24-hour food intake data. Linear regression was used to examine the relationship among health behaviors (PA and diet), stress and cardiometabolic health. An interaction between stress and health behaviors was explored. Lastly, intervention implementation, PA environment (PAE) scores, student demographics and objectively measured student school-time moderate-to-vigorous physical activity (MVPA) were collected from FLEX. Linear regression was used to examine the relationship between employee MVPA and (1) intervention implementation, accounting for stress, and (2) student school-time MVPA. The impact of the PAE on the relationship between employee MVPA and intervention implementation was explored. RESULTS: Findings from the focus groups (10 sessions, N=62) highlighted the importance of an organizational culture of wellness. Barriers included High Stress, Demanding Job, Lack of Wellness Culture, and Unhealthy Food. Facilitators included a Desire to Adopt Healthy Behaviors and Role Model, Sufficient Health Knowledge, and a Strong Social Network. Seventy-four employees (66% teachers) participated in Wellness Assessments. Overweight/obesity, high TC and LDL-C were observed in 47% (mean BMI: 25.6 kg/m2), 4%, and 34%, respectively, and MVPA was low (median: 17 min/day). Significant positive associations were identified between MVPA and cardiometabolic health. The relationship between MVPA and BMI was modified by stress (p-for-interaction=0.001), with higher levels of stress associated with a diminished protective association between MVPA and BMI. Higher stress was also associated with lower implementation (p<0.0001). Contrary to our hypothesis, higher employee MVPA was associated with lower student school-time MVPA (p=0.0002) and lower implementation (p<0.0001), with a stronger negative relationship in schools with higher PAE scores (p-for-interaction <0.0001). CONCLUSION: Our findings demonstrate physical inactivity and high stress among school employees, and suggest that this population would be receptive to wellness programming if barriers were minimized. Promising approaches to employee health promotion include wellness champions, accountability, and convenience. Observed relationships between employee PA and both implementation and student PA, which were contrary to our hypotheses, warrant further investigation as our analysis was limited by school-level employee PA data. Future studies should measure individual-level PA of teachers and champions delivering programming. This work provides a foundation for future research examining the impact of school employee wellness on both employee and student health, as well as on the implementation of school-based student PA programs.Thesis (Ph.D.)--Tufts University, 2018.Submitted to the Dept. of Biochemical and Molecular Nutrition.Advisor: Jennifer Sacheck.Committee: Kenneth Chui, Christina Economos, Alice Lichtenstein, and Stella Volpe.Keywords: Nutrition, and Health education
The Endogenous Retroviral Transcriptome in Melanoma
No full textAbstract: Human endogenous retroviruses (HERVs) are retroviral sequences passed from parent to offspring in a Mendelian fashion. Due to relatively recent endogenization and correlation to human illness, interest in the HERV-K (HML-2) subclade has increased. Expression of HML-2 - specific transcripts and proteins in melanoma cell lines was first discovered about a decade ago. Since there are at least 96 known HML-2 proviruses within the human genome, others have studied the HML-2 transcriptome in melanoma to identify the proviral sequences responsible for such expression. More recently, cDNA cloning frequency was used to detect HML-2 expression in melanoma cell lines and patient samples. Though they were able to detect the expression of several proviruses, cDNA cloning frequency is not as sensitive as RNA-sequencing and therefore they could have missed the expression of poorly expressed proviruses or the expression of rare proviruses. Furthermore, determining transcriptional mechanisms responsible for HML-2 expression in melanoma using cDNA cloning frequency data would be difficult while one could easily do this using a stranded library. Due to the potential role of expressed rare HML-2 proviruses in cancer etiology, and to understand transcriptional mechanisms responsible for HML-2 expression in melanoma, I submitted cellular RNA from five melanoma cell lines and three primary melanocyte populations for RNA-seq. I detected five proviruses that were uniquely expressed in melanoma compared to primary melanocytes. 7q22.2 was the highest expressing provirus followed by 3q12.3, which based on comparison to breast cancer and Tera-1s was only detected in cancerous cell lines. Most proviruses that were expressed in melanoma were young, human specific, and were mostly located in extragenic regions and driven by sense transcription. Two proviruses - 7p22.1a and 7p22.1b - contain intact ORFs for Env, yet I was unable to detect the presence of Env in whole cell lysate. Furthermore, three proviruses were capable of LTR-driven transcription in some of my melanoma cell lines which appears to be partially driven by transcription factor binding to LTRs. In conclusion, this work expands upon the known HML-2 transcriptome in melanoma while offering a larger view on HML-2 expression in cancer. It also shows one potential cause of HML-2 expression in melanoma and identifies the potential proviruses responsible for previous HML-2 protein production. Future work should include analyzing the effect epigenetic regulation has on HML-2 expression in cancer. Furthermore, future work should focus on analyzing patient samples to identify unique proviruses expressed in cancer so HML-2 expression can be evaluated for potential therapeutic and diagnosis purposes.Thesis (Ph.D.)--Tufts University, 2018.Submitted to the Dept. of Genetics.Advisor: John Coffin.Committee: Philip Hinds, Naomi Rosenberg, Jack Lenz, and Ralph Isberg.Keyword: Genetics
Anthocyanin and phenolic derivatives in blueberry juice produce CYP3A inhibition in vitro, and identification of these compounds and related derivatives in human plasma
No full textAbstract: Interactions of natural products with prescription drugs have become an issue of medical and public health concern. Blueberry juice at low concentrations produces inhibition of cytochrome P450 (CYP) 3A activity in vitro1. As the pharmacologically active constituents in blueberry juice, anthocyanin and phenolic reveal inhibit effect on CYP3A. Of 4 anthocyanin derivatives and 3 phenolic compounds were measured as potential inhibitor in screen inhibition test, result showed that Malvidin-3-glucoside, Peonidin-3-glucoside, Delphinidin-3-glucoside, Cyanidin-3-glucoside and Quercetin inhibited examined human microsome in a concentration-dependent manner featuring IC50 values from 8.8uM up to 89.2uM. To better understand the absorption and pharmacokinetic profile of blueberry anthocyanin and phenolic after consumed by human, a clinical study was involved. In human study, 12 healthy volunteers were required to take either water (300ml) or 50:50 mixture of lowbush and highbush blueberry juice (300ml) twice a day, and the blood samples were drawing during 12h after index substrate administration. Here, proteins remove, liquid-liquid extraction, high-performance liquid chromatography and mass spectrometry techniques are described for isolation, separation and identification of anthocyanin and phenolic in human plasma.Thesis (M.S.)--Tufts University, 2018.Submitted to the Dept. of Pharmacology and Drug Development.Advisor: David Greenblatt.Keyword: Pharmacology
Appropriate household water treatment methods in Ethiopia: household use and associated factors based on 2005, 2011, and 2016 EDHS data.
No full textBackground: Diarrheal disease attributable to water and sanitation can be prevented using point-of-use water treatment. In Ethiopia, a small number of households treat water at point-of-use with appropriate methods. However, evidence on factors associated with household use of these treatment methods is scarce. Therefore, this study is intended to explore the household use of appropriate point-of-use water treatment and associated factors in Ethiopia.Keywords: Education of household head, Household use, Water treatment, Wealth status.Springer Open
MySafeRx: a mobile technology platform integrating motivational coaching, adherence monitoring, and electronic pill dispensing for enhancing buprenorphine/naloxone adherence during opioid use disorder treatment: a pilot study.
No full textBackground: While buprenorphine/naloxone (B/N) is approved for opioid use disorder treatment, effective delivery of B/N comes with significant challenges. Most notably, many patients do not take medication daily as prescribed; this non-adherence worsens treatment outcomes, increases healthcare costs, and leads to persistent worries of diversion among providers and policymakers. The present study examines the feasibility, usability, and acceptability of MySafeRx—a mobile technology platform integrating motivational coaching, adherence monitoring, and electronic pill dispensing designed to address the challenges of office-based opioid treatment (OBOT) with B/N.Springer Open
Nusselt Numbers for Superhydrophobic Microchannels and Shrouded Longitudinal-Fin Heat Sinks
No full textAbstract: Nusselt numbers that are relevant, but not limited, to thermal management of electronics are computed in this thesis. The first two parts of the thesis compute Nusselt numbers for liquid flow between parallel plates that are textured with ridges oriented parallel to the flow. The configurations analyzed are both plates textured, and one plate textured as such and the other one smooth and adiabatic. The flow is laminar and the liquid is in the Cassie state on the textured surface(s). The menisci are flat and adiabatic, and the ridges are isothermal. First, axial conduction is neglected and the three-dimensional developing temperature field is computed assuming a hydrodynamically developed flow, i.e., the Graetz-Nusselt problem is solved. Then, the assumption of negligible axial conduction is relaxed, i.e., the Extended Graetz-Nusselt problem is solved. Effects of viscous dissipation and (uniform) volumetric heat generation are also considered. The last two parts of the thesis are relevant to conjugate forced-convection heat transfer through longitudinal-fin heat sinks. The third part computes and tabulates conjugate Nusselt numbers for such heat sinks. Importantly, the analysis accounts for axial conduction in the coolant and the fin. The flow is laminar, and simultaneously-developing. The heat sink has an adiabatic shroud and its base is isothermal. A conjugate boundary condition applies at the fin-coolant interface to impose continuity of the temperature field and heat flux there. In the last part of the thesis, an algorithm is presented to simultaneously optimize the geometry of an array of such heat sinks utilizing the conjugate Nusselt number tabulations. The optimization algorithm models heat transfer in a circuit pack using the Flow Network Modeling method. The resulting system of nonlinear algebraic equations constitutes the implicit constraints of the optimization problem. The objective function and the explicit constraints of the optimization problem are user defined and arbitrary. The optimization problem is iteratively solved using the Barrier Function method in conjunction with the Trust Region method.Thesis (Ph.D.)--Tufts University, 2018.Submitted to the Dept. of Mechanical Engineering.Advisor: Marc Hodes.Committee: Erica Kemmerling, James Adler, and Alan Lyons.Keyword: Mechanical engineering