Protective Role of <Emphasis Type="SmallCaps">l</Emphasis>-Arginine Against Free-Radical Mediated Oxidative Damage in Patients with Unstable Angina

Unstable angina is a critical condition of heart resulting from narrowing of vessels supplying blood to heart. Ischemia of the myocardium leads to oxidative stress and severe tissue damage. The objective of the present study was to determine the effect of l-arginine administration on the oxidant–antioxidant homeostasis which otherwise gets imbalanced in patients with cardiovascular diseases. The results obtained, show improvement in the oxidant–antioxidant levels of the subjects upon incorporation of l-arginine. Our findings suggest that supplementation of l-arginine along with regular anti-anginal therapy may be beneficial to the patients of unstable angina.     

Middle School Teachers’ Use of Mathematics to Make Sense of Student Solutions to Proportional Reasoning Problems

Mathematics teacher education aims to improve teachers’ use of mathematical knowledge to support teaching and learning, an aspect of pedagogical content knowledge (PCK). In this study, we interviewed teachers to understand how they used mathematics to make sense of student solutions to proportional reasoning problems. The larger purpose was to find accurate ways of categorizing teachers’ ability to do this vital aspect of teaching and thereby to inform assessment, teacher education, and professional development. We conjectured that teachers’ PCK for proportional reasoning could be reliably described in terms of attention to quantitative meanings in story problem contexts and in terms of understanding naïve forms of proportional reasoning. Instead, our findings reveal that individual teachers used a variety of means to make sense of (1) cognitively similar student solutions to different tasks and (2) mathematically related steps of a student solution within a single task. These findings illustrate the complexity of PCK for the topic of proportional reasoning and suggest the limits of what can be inferred about teacher knowledge from teachers’ evaluations of student solutions. We discuss implications for teacher education and assessment.     

Systems biology

Systems biology seeks to study biological systems as a whole, contrary to the reductionist approach that has dominated biology. Such a view of biological systems emanating from strong foundations of molecular level understanding of the individual components in terms of their form, function and interactions is promising to transform the level at which we understand biology. Systems are defined and abstracted at different levels, which are simulated and analysed using different types of mathematical and computational techniques. Insights obtained from systems level studies readily lend to their use in several applications in biotechnology and drug discovery, making it even more important to study systems as a whole.     

Projectile motion with quadratic damping in a constant gravitational field

The motion of a projectile in a constant gravitational field is an age-old problem. If there is no resistive force, the problem is simple. However, with the intoduction of resistive forces, the complexity of the problem increases. Recently, there has been a growing interest in the problem of projectile motion under a resistive force proportional to the square of velocity. The problem for resistive force proportional to vv cannot be solved in closed analytical form. A series solution of the equation leads to divergent series for x (t) and y (t) for reasonable values of the initial speed and angle of projection. However, we demonstrate that by inverting the series for x (t), i.e., expressing t in terms of x, and substituting this in y (t) one can express y in terms of x which is a highly convergent series and one can obtain the path of projectile with a few terms of the series. We further demonstrate that one can obtain the path even with a few terms of the divergent series for x (t) and y (t) by using extrapolation methods.     

What’s new in computers

Lately there has been a lot of excitement about disruptive forms of ‘money’ — cryptocurrencies. This article traces the evolution of cryptocurrencies focusing on the enabling technologies and some theoretical foundations. We shall also explore the challenges they pose to well-established monetary systems.     

From inactivity to encouragement: the contribution of Lord Elphinstone to the educational development of the Madras Presidency (1837–1842)

In light of the focus placed on English education by the colonial government, and the petition signed by 70,000 local inhabitants of the Madras Presidency, Lord John Elphinstone, the Governor, made efforts to disseminate English education during his governorship (1837–1842). Spurred on by the petition, Elphinstone wrote two fundamental educational minutes, in 1839 and 1841, and established Madras High School. Later, the School was transformed into Presidency College and became the first home of the University of Madras. Elphinstone’s planning led to the first systematic effort by the Madras government to impart English education. Subsequently, Elphinstone emphasised the dissemination of secular education and inclusion of native people in educational administration. Against this background, this paper discusses the contribution of Elphinstone to the educational development of Madras. It also questions the historiographical neglect of Elphinstone and challenges the established post-colonial discourse that the establishment of English institutions was a ‘colonialist’ imposition.     

Serum total PSA and free PSA in breast tumors

Now a days measurement of molecular forms of PSA has gained importance in clinical practice. Several studies have demonstrated the production of PSA in female tissues, such as breast. The present piece of work has been undertaken with an objective to estimate the relative proportion of the molecular forms of PSA in serum along with serum testosterone in benign and malignant breast tumor cases and to analyze their association with the severity of the disease process 34 malignant and 26 benign breast disease cases along with 33 healthy controls of same age group were enrolled in this study for evaluation. Serum testosterone was measured by ELISA, whereas serum total PSA (TPSA) and free PSA (FPSA) were estimated by electrochemiluminescence immunoassay. A significant rise of fasting plasma glucose along with prominent dyslipidemia was observed in breast tumor cases. Marked rise in serum testosterone as well as TPSA and FPSA was documented in both benign and malignant breast tumor cases. Serum testosterone revealed a significant positive association with both TPSA and FPSA pointing towards an etiological association between them. However, surgical removal of tumor mass resulted in a marked decline of presurgical value of both TPSA and FPSA with a non-significant fall in serum testosterone revealing tumor tissue as the source of FPSA and TPSA. Thus, estimation of PSA provides prognostic information that may assist in future treatment.     

Supporting Online PBL: Design Considerations for Supporting Distributed Problem Solving

This study considers how four groups of education graduate students worked in a distributed problem-based learning (PBL) environment using an asynchronous threaded discussion tool. The analyses consider how the students were able to interact with each other using the tool and how they worked together to define the problem and identify key issues to explore. The outcomes include some design considerations for tools to support these activities as well as insight about how students may work together to solve a problem in a distributed environment.     

Establishing the overall service quality of engineering education: fuzzy logic approach

Measuring overall service quality (OSQ) is gaining prominence in higher education due to the increased competition among engineering education institutions (EEIs) and growing awareness about value for money among the public. Determination of OSQ on certain institutional aspects is done by various agencies throughout the world. Each system uses a different set of weighted indicators to measure the overall service quality of institutions. Five service quality factors, namely professionalism, integrated education, facilities, responsiveness and empathy are considered in the study. Trapezoidal fuzzy numbers are used to determine the aggregate weights of the factors to handle the vagueness present in the linguistic values of the stakeholders’ subjective opinions. Final weights of the factors are assessed by taking the distances of each factor between Fuzzy Positive Ideal Rating and Fuzzy Negative Ideal Rating. An illustrative study is presented to determine the OSQ of EEIs. The results help to focus on the factors which need immediate attention to enhance the quality of EEIs.     

Tide–surge interaction model including air bubble effects for the coast of Bangladesh

An estimate of water levels due to the interaction of tide and surge associated with a storm including air bubble effects is made along the coastal region of Bangladesh. For this purpose, a vertically integrated shallow water model in Cartesian coordinate system is developed introducing air bubbles and is solved using nested finite difference schemes. A fine grid model covering the region between 21°15′N to 23°N and 89°E to 92° E has been nested into a coarse grid model covering the region between 15°N to 23°N and 85°E to 95°E in the Bay of Bengal to incorporate all the major islands and coastal bending accurately. By applying tidal forcing through the southern open boundary of the coarse grid model appropriate tidal conditions are generated in the problem domain. Numerical experiments are performed with the help of the model to simulate water levels due to tide and surge interaction including air bubble effects associated with the tropical storm of April 1991. The model results are found to be reasonable and the model can be found to simulate higher water levels in the presence of air bubbles.