Learning Boolean Halfspaces with Small Weights from Membership Queries

We consider the problem of proper learning a Boolean Halfspace with integer weights $\{0,1,\ldots,t\}$ from membership queries only. The best known algorithm for this problem is an adaptive algorithm that asks $n^{O(t^5)}$ membership queries where the best lower bound for the number of membership queries is $n^t$ [Learning Threshold Functions with Small Weights Using Membership Queries. COLT 1999] In this paper we close this gap and give an adaptive proper learning algorithm with two rounds that asks $n^{O(t)}$ membership queries. We also give a non-adaptive proper learning algorithm that asks $n^{O(t^3)}$ membership queries

Kepentingan Rusia Meningkatkan Penjualan Senjata Kepada Rezim Bashar Al-assad dalam Konflik Suriah Tahun 2011-2013

This research to explain the reasons of Russia supplies weapon to bashar al-assad in Syria conflict. Syria is one of the countries in Middle East that is experiencing political turmoil with people demanding President Bashar al-Assad retreated from his position. This conflict has claimed of so many people life that western countries lead to implement the arms and other economic sanctions against Syria but the effort was opposed by Russia through its veto.The foreign policy theory tries to explain the decision of Russia as a form of maintaining power in Middle East, particularly in Syria. in addition, Rusia Russia has an interest in Syria. The scope of this study is from 2011-2013.Keywords: Foreign Policy, National Interest, Conflict, trade of weapo

Pathogenic Activation of Mesenchymal Stem Cells is induced by the Disease Microenvironment in Systemic Sclerosis

Objective: In systemic sclerosis (SS c), a persistent tissue repair process leads to progressive fibrosis of the skin and internal organs. The role of mesenchymal stem cells (MSC s), which characteristically initiate and regulate tissue repair, has not been fully evaluated. We undertook this study to investigate whether dividing metakaryotic MSC s are present in SS c skin and to examine whether exposure to the disease microenvironment activates MSC s and leads to transdifferentiation. Methods: Skin biopsy material from patients with recent‐onset diffuse SS c was examined by collagenase spread of 1‐mm–thick surface‐parallel sections, in order to identify dividing metakaryotic stem cells in each tissue plane. Adipose‐derived MSC s from healthy controls were treated with dermal blister fluid (BF ) from patients with diffuse SS c and profiled by next‐generation sequencing, or they were evaluated for phenotypic changes relevant to SS c. Differential responses of dermal fibroblasts were studied in parallel. Results: MSC ‐like cells undergoing active metakaryotic division were identified in SS c sections (but not control sections) most prominently in the deep dermis and adjacent to damaged microvessels, in both clinically involved and uninvolved skin. Furthermore, exposure to SS c BF caused selective MSC activation, inducing a myofibroblast signature, while reducing signatures of vascular repair and adipogenesis and enhancing migration and contractility. Microenvironmental factors implicated in inducing transdifferentiation included the profibrotic transforming growth factor β, the presence of lactate, and mechanosensing, while the microenvironment Th2 cytokine, interleukin‐31, enhanced osteogenic commitment (calcinosis). Conclusion: Dividing MSC ‐like cells are present in the SS c disease microenvironment where multiple factors, likely acting in concert, promote transdifferentiation and lead to a complex and resistant disease state

Factors influencing the geographic distribution of physicians in Iran: A qualitative study

Introduction: The uneven geographic distribution of physicians has been a longstanding important issue worldwide. Different policies have been recently employed in Iran, with the aim of bridging the gap. This study aimed to explore factors influencing the distribution of specialist physicians in Iran and investigate the effects of newly established policies on attracting and retaining physicians in rural and remote areas. Methods: This qualitative study was conducted in 2012. Qualitative data were obtained through an open-ended questionnaire and by reviewing relevant documents. Participants were 82 key officials from medical universities, who were directly involved in the distribution of physicians across the country, including vice chancellors for treatment affairs, managers for treatment affairs, and human resources experts. Thematic analysis was used to analyse qualitative data. Results: Four main factors influencing the distribution of physicians were explored, namely external, contextual, individual, and organizational factors. The decision to practice in rural areas was mainly influenced by socioeconomic characteristics of the designated areas and personal attributes of physicians, including sex, income expectations, and rural background. Participants also asserted that the implemented policies had a major positive influence on the distribution of physicians. In addition, participants believed that the improvement in the distribution of physicians had both positive economic and health impacts in underdeveloped areas. Conclusions: It seems that the regional distribution and supply of physicians have been improved in the light of the implemented policies in recent years. The study also revealed that a number of factors influence physician choices to stay and practice in rural and underdeveloped areas. Policies such as providing more financial and non-financial incentives, reducing disparities between physicians' income in rural and metropolitan areas, selection of students with rural background, and supportive measures for physicians working in underserved areas were recommended. © H Ravaghi, E Taati, Z Abdi, A Meshkini, S Sarvarizadeh, 2015

The planning of educational facilities in new towns.

The aim of this study is to analyse the nature of educational facilities planning processes in new towns; how these processes are influenced by the framework of procedures at central and local government, Development Corporation and church authority levels; to contribute to the understanding of the effects of overall new town development upon the planning and provision of educational facilities and to suggest alternative measures to deal with and avoid the problem situations that were observed in this study. The first step towards achieving these aims involved a review of the statutory, administrative and financial characteristics of the authorities involved in the planning and provision of educational facilities in new towns, including their links and their liabilities towards each other. The second stage of exploration was a comparison of the twenty-one English new towns in terms of their overall population, pupil population, education, housing and socia-economic characteristics, with the underlying aims of, (a) devising a conceptual framework for this study and, (b) selecting appropriate case-studies to permit the study of problems in depth. The three case-studies were selected on the basis of their dissimilarities, against such variables as (i) belonging to a different stage of new town development, (ii) overall population, pupil population and educational system characteristics, (iii) experiencing different planning and management arrangements. The next stage of exploration involved an historical analysis which considered the relations between the educational facilities structure of each case-study in conjunction with the overall development of the new town, in particular its housing and employment structures. The method adopted was the identification and selection of major Decision/Problem areas within~ the. educational facilities structure of each new town followed by an a~ys1s of the causes and consequences of problem situations. It became apparent that in spite of the differences between the three case-studies (the essential basis upon which they were originally selected), they shared some common Decision/Problem areas. These similarities occurred in spite of the different methods that were adopted by the relevant authorities to tackle the problem situations. The analysis of the three case-studies confirmed the conceptual framework adopted in the second stage. It was concluded that the economic situation of a new town has such an impact upon its housing and educational facilities structures, that without a comprehensive approach to these interrelated problems and without a guarantee by the Government about the provision of necessary job opportunities and steady development of the new towns, the kind of problems that have been created in the education systems of these new towns can not be solved. This is because these are not purely educational problems and their resolution goes far beyond educational policies and regulations. The approach advocated in this study is aimed at a proper understanding of educational problems by the authorities involved in educational facilities planning of new towns and the achievement of the recognition of official responsibility for all aspects of new town development by the Government, not just during the development period of new towns, but also in dealing with problems inherent in interrupted development programmes and declining populations. At the same time this study revealed that there is a need for more co-operation between all the involved authorities and that there is a need for some changes in some educational statutes, policies and regulations which have imposed constraints upon a more rational planning process for educational facilities

Relationship between personal characteristics of specialist physicians and choice of practice location in Iran

Introduction: Uneven geographic distribution of physicians is a major healthcare issue in Iran. This study aimed to explore the relationship between personal characteristics of the recently graduated specialist physicians in Iran and their choice of practice location. Methods: A cross-sectional study was conducted to extract information with regard to 3825 recently graduated specialist physicians from all medical schools across Iran between 2009 and 2012. The relationship between physicians' personal attributes and their desire to practise in underdeveloped areas was analyzed using �2 test and logistic regression analysis. Results: Birthplace, sex, exposure to rural practice before residency program, place of residence, and year of graduation were associated with physicians' desire to practise in an underdeveloped area. The logistic regression showed that female physicians were less likely to choose underdeveloped areas to practise as compared with their male counterparts (OR=0.659, 95CI, 0.557-0.781, p�0.001). Physicians who lived in underdeveloped areas were nine times more likely to choose underdeveloped areas to practise as compared with those living in other areas (OR=8.966, 95CI, 4.717-17.041, p�0.001). Physicians who did not have previous exposure to rural practice were 28 less likely to choose to serve in the underdeveloped areas as compared to those who had such exposure (OR=0.780, 95CI, 0.661-0.922, p=0.004). Neither physicians' marital status nor their success in the board certification exam was associated with their choice of practice location. Conclusions: It seems that increasing the enrollment of physicians with a rural background in residency programs may solve the problem of uneven distribution of specialist physicians in Iran. Because female physicians are less willing to work in the underdeveloped areas than male physicians, increasing the number of male student admissions to residency programs, particularly in certain specialties that are more in demand in the underdeveloped areas, could alleviate the problem of uneven distribution of physicians in the short run. Further, programs that support raising the admissions of female students with a rural background into local medical universities along with providing incentives to encourage them to live and work in rural areas should be put on the policy agenda. © James Cook University 2016

PENGUJIAN KEMAMPUAN ADSORPSI DARI ADSORBEN ALUMINA AKTIF UNTUK MESIN PENDINGIN TENAGA SURYA

Akhir-akhir ini mesin pendingin siklus adsorpsi semakin banyak diteliti oleh para ahli karenadisamping ekonomis juga ramah lingkungan dan menggunakan energy terbarukan yaitu energi surya.Agar proses adsorpsi dan desorpsi mesin pendingin adsorpsi dapat berjalan dengan baik perludiketahui jumlah perbandingan yang ideal antara adsorben dengan refrigeran yang digunakan. Disiniuntuk mencari perbandingan antara absorben alumina aktif menggunakan baut maupun tidakmenggunakan baut. Data tersebut dapat dicari menggunakan alat penguji kapasitas adsorpsi. Alatpenguji kapasitas adsorpsi yang digunakan dilengkapi dengan lampu halogen 1000 W sebagai sumberpanas. Adsorber pada alat penguji ini terbuat dari bahan stainless steel yang bertujuan agar tahanterhadap korosi akibat dari variasi refrigeran yang digunakan. Alumina aktif yang digunakan sebagaiadsorben sebanyak 1 kg. Sedangkan variasi refrigeran yang digunakan yaitu amonia. Kapasitas amoniayang dapat diadsorpsi dan didesorpsi oleh adsorben alumina aktif mengunakan baut diisolasi adalahsebanyak 300 mL. Sedangkan kapasitas amonia yang dapat diadsorpsi dan didesorpsi oleh adsorbenalumina aktif tidak menggunakan baut diisolasi adalah sebanyak 220 mL

Seroepidemiological Study of Human Hydatidosis in Meshkinshahr District, Ardabil Province, Iran

Background: The aim of this study was to conduct a sero-epidemiological survey in Meshkinshahr, Arda­bil Province, northwestern Iran to detect the rate of hydatidosis in the city and nearby villages. Literature shows that no such study has been conducted so far.Methods: Overall, 670 serum samples were collected from 194 males and 476 females from patients re­ferred to different health centers of the region. All patients filled out a questionnaire and an informed con­sent. Sera were analyzed using indirect-ELISA test. Ten μg /ml antigens (Antigen B derived from hydatid cyst fluid), serum dilutions of 1:500 and conjugate anti-human coombs with 1:10000 dilutions were util­ized to perform the test. Data analysis was conducted using SPSS software ver. 11.5. Results: The seroprevalence of human hydatidosis was 1.79% by ELISA test in the region. This rate for fe­males was 1.68% and males 2.6%, respectively. There was no significant difference as regards all fac­tors studied and the seropositivity. According to job, farmers and ranchmen had the highest rate of infec­tion as 3.17%. The sero-prevalence of infection was 2.6%% in illiterate people which showed the highest rate. As regards residency, urban life showed no significant difference with rural life (1.1% vs. 2.58%). Age group of 69-90 yr old, with 4.62% as prevalence had the highest rate of positivity.Conclusion: Obtained sero-prevalence of hydatidosis shows more or less a resemblance to other cities of Iran, although due to the specific condition of the city we expected more rate of sero-positivity