Physical Multi-Layer Phantoms for Intra-Body Communications

This paper presents approaches to creating tissue mimicking materials that can be used as phantoms for evaluating the performance of Body Area Networks (BAN). The main goal of the paper is to describe a methodology to create a repeatable experimental BAN platform that can be customized depending on the BAN scenario under test. Comparisons between different material compositions and percentages are shown, along with the resulting electrical properties of each mixture over the frequency range of interest for intra-body communications; 100 KHz to 100 MHz. Test results on a composite multi-layer sample are presented confirming the efficacy of the proposed methodology. To date, this is the first paper that provides guidance on how to decide on concentration levels of ingredients, depending on the exact frequency range of operation, and the desired matched electrical characteristics (conductivity vs. permittivity), to create multi-layer phantoms for intra-body communication applications

Designing a low cost XY stage for abrasive water jet cutting

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.Includes bibliographical references (p. 67).This thesis guides the reader through the design of an inexpensive XY stage for abrasive water jet cutting machine starting with a set of functional requirements and ending with a product. Abrasive water jet cutting allows for mass customization of 2D parts, such as inlaid tiles. Most water jet cutters are based on a prismatic-prismatic design (gantry type). In an effort to reduce the number of precision parts in the machine, a rotary-rotary parallel drive design is proposed. The proposed mechanism will be actuated by electric DC windshield wiper motors directly coupled to the links, this eliminates the need for gearing mechanisms that add up to the total cost and complexity of the design. Kinematics of the design is simulated for a working area of 310mm x 310mm. Dynamic analysis is performed and the concepts of decoupled and configuration invariant inertia are derived, simplified to a set of conditions on the kinematic structure/mass properties of the arm linkages and applied to significantly simplify the mechanism's control system. The XY stage was designed to be inexpensive and small enough to be placed in hardware stores, garages and small machine shops. A vision of water jet cutters sold in boxes stacked on shelves in Wal-Mart, available for all machinists, artists, schools, and industries might one day thus become a reality if the pumps could also be made cheaply.by Fadi Abu Ibrahim.S.M

Precocious puberty in an infant with hepatoblastoma: a case report

<p>Abstract</p> <p>Introduction</p> <p>The syndrome of isosexual precocious puberty associated with primary malignant hepatic tumors is rare. All previously reported cases in the literature are old and prognosis was grim.</p> <p>Case presentation</p> <p>We present the case of a 15-month-old Asian male baby who presented with precocious puberty associated with hepatoblastoma. Serum concentrations of alpha-fetoprotein and free testosterone were elevated, as was beta human chorionic gonadotropin hormone. He was treated with six courses of chemotherapy and underwent surgery. His surface markers as well as free testosterone level returned to normal during therapy. The child has now been off therapy for 18 months with no evidence of tumor recurrence at follow-up.</p> <p>Conclusion</p> <p>Virilizing hepatoblastoma is rare and reported with poor outcome, but the development of new chemotherapeutic agents and complete surgical resection are promising.</p

The reasons behind the weaknesses of writing in English among pre-year students' at Taibah University

This paper is intended to explore the reasons behind the weakness of writing among pre-year students at Taibah University.For the purpose of this study, only one research question was provided and discussed.The participants of this study were 10 pre-year male students at Taibah University "Yanbu Branch" in Saudi Arabia for the academic year 2012-2013. This study is a qualitative study.The data for this study was collected through semi-structured interview from male students only. The findings of this study revealed that grammatical weakness, knowledge and understand, less practice and educational background were the main themes discovered by the students.The implementation of this study may help the teachers to resolve the problem and may find some strategies to help them.It is hoped that this study would enhance the findings all over the world to improve students writing, especially in the Arab societ

أثر المساعدات المالية الإنمائية المقدمة إلى سورية في فجوة الموارد المحلية

يهدف هذا البحث إلى دراسة أثر المساعدات المالية الإنمائية في فجوة الموارد المحلية في سورية خلال الفترة 2000-2019. حيث تم الاعتماد في دراسة العلاقة طويلة الأجل بين المساعدات المالية الإنمائية المقدمة لسورية وفجوة الموارد المحلية على اختبارJohansen للتكامل المشترك, وعلى نموذج (VECM) للتحقق من اتجاه سببية العلاقة طويلة الأجل, واختبار سببية كرانجر للتحقق من وجود العلاقة قصيرة الأجل, كما تم اكتشاف أثر المساعدات المالية الإنمائية المقدمة إلى سورية على فجوة الموارد المحلية من خلال دوال الاستجابة النبضية وتحليل التباين. حيث أظهرت نتائج اختبارJohansen للتكامل المشترك بأن هنالك علاقة طويلة الأجل بين المساعدات المالية الإنمائية المقدمة إلى سورية وفجوة الموارد المحلية خلال الفترة 2000-2019. في حين أوضح نموذج (VECM) بأن هنالك علاقة سببية طويلة الأجل وباتجاهين بين المساعدات المالية الإنمائية المقدمة إلى سورية وفجوة الموارد المحلية. أما نتائج اختبار سببية كرانجر فقد تطابقت مع نتائج نموذج (VECM) وذلك فيما يتعلق بالعلاقة قصيرة الأجل, حيث أظهرت نتائج هذين الاختبارين بأن هنالك علاقة قصيرة الأجل بين المساعدات المالية الإنمائية المقدمة إلى سورية وفجوة الموارد المحلية خلال الفترة 2000-2019. وقد بينت دوال الاستجابة النبضية وتحليل التباين بأن هنالك أثراً للمساعدات المالية الإنمائية المقدمة إلى سورية على فجوة الموارد المحلية ولكن هذا الأثر كان ضعيفاً جداً

From Charity to Change: Trends in Arab Philanthropy

From Charity to Change: Trends in Arab Philanthropy, provides a preliminary overview of Arab philanthropy in eight countries of the region including: Egypt, the Hashemite Kingdom of Jordan, Lebanon, Palestine, the United Arab Emirates, Qatar, the Kingdom of Saudi Arabia and Kuwait. The purpose of the study was to document the varying forms of institutionalized philanthropy that currently exist as well as provide recommendations for how philanthropy can become more effective.

COVID-19 and diabetes in 2020: a systematic review

Attempts were made to review the literature on diabetic patients who experience complications when they contract COVID-19, and to determine whether ethnicity and other risk factors play an important role in the development of symptoms and their severity, as well as responding to medications. A literature search was performed using fve keywords, namely COVID-19, diabetes, ethnicity, medications, and risk factors between January 2019 and December 2020 using electronic databases such as PubMed, Science Direct, Google Scholar, Springer Link, and Scopus. Forty studies were included. The review indicated that diabetes was a signifcant risk factor for poorer outcomes and increased mortality associated with COVID-19. There were several risk factors for diabetic patients that increased their likelihood of poorer outcomes associated with COVID-19. These included black and Asian ethnicity, male sex with high BMI. In conclusion, patients with diabetes of black or Asian origin with high BMI, male sex, and older age had an increased risk of poorer outcomes associated with COVID-19. This highlights the importance of considering the history of the patient in prioritising care and treatment

The Use of Stem Cells in Burn Wound Healing: A Review

Burn wound healing involves a series of complex processes which are subject to intensive investigations to improve the outcomes, in particular, the healing time and the quality of the scar. Burn injuries, especially severe ones, are proving to have devastating effects on the affected patients. Stem cells have been recently applied in the field to promote superior healing of the wounds. Not only have stem cells been shown to promote better and faster healing of the burn wounds, but also they have decreased the inflammation levels with less scar progression and fibrosis. This review aims to highlight the beneficial therapeutic effect of stem cells in burn wound healing and to discuss the involved pathways and signaling molecules. The review covers various types of burn wound healing like skin and corneal burns, along with the alternative recent therapies being studied in the field of burn wound healing. The current reflection of the attitudes of people regarding the use of stem cells in burn wound healing is also stated