Recovering Solar Toroidal Field Dynamics From Sunspot Location Patterns

We analyze both Kitt Peak magnetogram data and MDI continuum intensity sunspot data to search for the following solar toroidal band properties: width in latitude and the existence of a tipping instability (longitudinal m=1 mode) for any time during the solar cycle. To determine the extent which we can recover the toroidal field dynamics, we forward model artificially generated sunspot distributions from subsurface toroidal fields we assigned certain properties. We analyzed two sunspot distribution parameters using MDI and model data: the average latitudinal separation of sunspot pairs as a function of longitudinal separation, and the number of sunspot pairs creating a given angle with respect to the E-W direction. A toroidal band of 10 degrees width with a constant tipping of 5 degrees best fits MDI data early in the solar cycle. A toroidal band of 20 degrees width with a tipping amplitude decreasing in time from 5 to 0 degrees best fits MDI data late in the solar cycle. Model data generated by untipped toroidal bands cannot fit MDI high latitude data and can fit only one parameter at low latitudes. Tipped toroidal bands satisfy chi squared criteria at both high and low latitudes. We conclude this is evidence to reject the null hypothesis - that toroidal bands in the solar tachocline do not experience a tipping instability - in favor of the hypothesis that the toroidal band experiences an m=1 tipping instability. Our finding that the band widens from ~10 degrees early in the solar cycle to ~20 degrees late in the solar cycle may be explained in theory by magnetic drag spreading the toroidal band due to altered flow along the tipped field lines.Comment: This paper is accepted to Astrophysical Journal, September 2005 issu

Determinants of Actual Usage of Computer among Mathematics, Science and English Language Teachers in Secondary Schools in Selangor, Malaysia

As we are heading towards achieving the goal of Vision 2020, numerous changes have been implemented in the system of education. Among them would be the paradigm shift from the traditional mode of teaching to one that is of the information technology based especially among the Mathematics, Science and English language (MSE) teachers. Numerous incentives were given to the MSE teachers to use the computer in schools but preliminary observations found that they are not fully utilizing these facilities. The aim of this study is to identify factors influencing the actual usage of computer (AUC) among secondary school MSE teachers. The factors investigated were attitude, perceived usefulness, perceived ease of use, computer self-efficacy, job relevance, computer compatibility, subjective norm and teachers’ demography. A self-administered survey questionnaire was sent to MSE secondary school teachers in 65 schools in the district of Petaling, in Selangor. Out of the 358 questionnaires, a total of 318 (88.9%) valid responses were used. The data collected were analyzed using exploratory data analysis, statistical descriptive and inferential statistics (t-test, One-way ANOVA, Pearson correlation, and multiple regression) using the SPSS. Overall, the study found that the AUC among MSE secondary school teachers were at the moderate level. Meanwhile, the socio-demographic factors of main subjects taught and training in computer usage showed significant differences in means of AUC. Besides, the constructs of attitude, perceived usefulness, perceived ease of use, job relevance, and computer compatibility showed significant positive relationship with AUC. The study too identified the best-fit model using the step-wise multiple regression and the best model explained 54.5% of variance in AUC. The most significant predictors of AUC were perceived ease of use, followed by perceived usefulness, job relevance, computer compatibility, and attitude. It is recommended that for MSE teachers to enhance on their level of AUC would need a concrete effort from the policy makers, school administrators, and teachers themselves. Future research is recommended to encompass a wider scope of constructs pertaining to AUC that incorporate among others financial incentives and type of school

Towards the Formal Specification and Verification of Maple Programs

In this paper, we present our ongoing work and initial results on the formal specification and verification of MiniMaple (a substantial subset of Maple with slight extensions) programs. The main goal of our work is to find behavioral errors in such programs w.r.t. their specifications by static analysis. This task is more complex for widely used computer algebra languages like Maple as these are fundamentally different from classical languages: they support non-standard types of objects such as symbols, unevaluated expressions and polynomials and require abstract computer algebraic concepts and objects such as rings and orderings etc. As a starting point we have defined and formalized a syntax, semantics, type system and specification language for MiniMaple

Automatic text summarization of konkani texts using pre-trained word embeddings and deep learning

Automatic text summarization has gained immense popularity in research. Previously, several methods have been explored for obtaining effective text summarization outcomes. However, most of the work pertains to the most popular languages spoken in the world. Through this paper, we explore the area of extractive automatic text summarization using deep learning approach and apply it to Konkani language, which is a low-resource language as there are limited resources, such as data, tools, speakers and/or experts in Konkani. In the proposed technique, Facebook’s fastText pre-trained word embeddings are used to get a vector representation for sentences. Thereafter, deep multi-layer perceptron technique is employed, as a supervised binary classification task for auto-generating summaries using the feature vectors. Using pre-trained fastText word embeddings eliminated the requirement of a large training set and reduced training time. The system generated summaries were evaluated against the ‘gold-standard’ human generated summaries with recall-oriented understudy for gisting evaluation (ROUGE) toolkit. The results thus obtained showed that performance of the proposed system matched closely to the performance of the human annotators in generating summaries

Immune Dysregulation in MDS: The Role of Cytokines and Immune Cells

Myelodysplastic syndrome (MDS) is a hematopoietic stem cell disorder affecting individuals over the age of 60 years. It is characterized by ineffective hematopoiesis and extensive apoptosis of hematopoietic cells. MDS patients are at a high risk of transforming in to acute myeloid leukemia. The main cause of apoptosis and escape from immune surveillance in MDS is immune dysregulation caused by a number of factors such as aberrant cytokine production and influence of various immune cells. In the past decade various pro-inflammatory cytokines and a number of immune cells such as Natural Killer cells, regulatory T cells, cytotoxic T cells, mesenchymal stem cells, myeloid derived suppressor cells and dendritic cells have been implicated in immune dysregulation leading to MDS pathogenesis. In this review we focus on the current data available on the role of these immune factors

Assessment of Immune Reconstitution Following Hematopoietic Stem Cell Transplantation

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a potential curative treatment for both congenital and hematological malignancies. Immune reconstitution after allogeneic hematopoietic stem cell transplantation is implicated in successful transplant outcomes such as overall survival and relapse-free survival. The reconstitution of immune cell subsets after HSCT occurs in different phases at different time points encompassing pre-engraftment, engraftment, and post-engraftment. The recovery of innate cellular immunity with the appearance of monocytes, dendritic cells, and natural killer cells in peripheral blood correlates with initiation of cellular engraftment. The cellular adaptive immunity is characterized by both thymic-independent expansion of T cells infused with graft and thymus-dependent expansion of naïve T cells derived from donor stem cells. The humoral immunity consists of B-cell reconstitution, which consists primarily of transitional and naïve subsets with the recovery of memory B cells that occur much later. In this review, we highlight the factors affecting immune reconstitution, the reconstitution of innate and adaptive immunity, techniques to assess immune reconstitution, and ways to enhance it

Termination of Triangular Integer Loops is Decidable

We consider the problem whether termination of affine integer loops is decidable. Since Tiwari conjectured decidability in 2004, only special cases have been solved. We complement this work by proving decidability for the case that the update matrix is triangular.Comment: Full version (with proofs) of a paper published in the Proceedings of the 31st International Conference on Computer Aided Verification (CAV '19), New York, NY, USA, Lecture Notes in Computer Science, Springer-Verlag, 201

Predicting solar cycle 24 with a solar dynamo model

Whether the upcoming cycle 24 of solar activity will be strong or not is being hotly debated. The solar cycle is produced by a complex dynamo mechanism. We model the last few solar cycles by `feeding' observational data of the Sun's polar magnetic field into our solar dynamo model. Our results fit the observed sunspot numbers of cycles 21-23 extremely well and predict that cycle~24 will be about 35% weaker than cycle~23.Comment: 10 pages 1 table 3 figure

Role of Academic Libraries in the age of MOOCs in India

The study aims to report the current growth of Massive Open Online Courses (MOOCs) and its evolution, features, benefits, various types, International and Indian scenarios, and challenges. The study also examines the role of academic libraries in the expansion of MOOCs in the present era. The study employed web content analysis and questionnaire methods to collect data related to the current growth of MOOCs in India. The study interviewed 75 students and 45 faculties of St. Teresa\u27s College, Ernakulam, to explore their perceptions of MOOCs as a higher education system and how Academic Libraries become their centre for MOOC courses. The study found that 75.3% of respondents joined/completed the MOOC courses, whereas some respondents had no ideas about it. Among the 75.3% of respondents who joined/completed the course, 89.4% of respondents completed one or two certification courses, 7.6% of respondents have completed 3 to 5 classes, and only 3% of respondents have completed between 6 to 10 online courses. The expansions of online education through MOOCs in India, such as the NPTEL and SWAYAM, have positively impacted the growth of Academic libraries