Student achievement conditioned upon school selection: Religious and secular secondary school quality in Bangladesh

In this paper we present new evidence on the impact of school characteristics on secondary student achievement using a rich dataset from rural Bangladesh. We deal with a potentially important selectivity issue in the South Asian context: the non-random sorting of children into madrasas (Islamic faith schools). We do so by employing a combination of fixed effects and instrumental variable estimation techniques. Our empirical results do not reveal any difference in test scores between religious and secular schools when selection into secondary school is taken into account. However, we document significant learning deficit by gender and primary school type: girls and graduates of primary madrasas have significantly lower test scores even after controlling for school and classroom-specific unobservable correlates of learning.     

A Synergistic Role of Myeloperoxidase and High Sensitivity Troponin T in the Early Diagnosis of Acute Coronary Syndrome

Aim of this study was to evaluate the role of Myeloperoxidase (MPO) and high sensitive Troponin T in the early diagnosis of acute coronary syndrome (ACS). This was a cross sectional study that comprised of 120 individuals of which 75 were cases and 45 healthy controls. On the basis of clinical history and 12 lead electrocardiogram initial diagnosis of ACS was made in the cases. MPO and high sensitive Troponin T (hs-cTnT) was measured in all the individuals. Levels of MPO were significantly higher in patients of ACS as compared to those in control group [medians: 15.40 (95 % CI 11.06–20.84) vs 5.84 (95 % CI 5.50–6.44)]. By taking the cut off as >11.87 U/mL for MPO, its sensitivity was 87 % (95 % CI 73.7–95.1), specificity was 97.3 % (95 % CI 90.6–99.7), positive predictive value was 94.6 % and negative predictive value was 92.6 %. Positive likelihood ratio was 33.0 while negative likelihood ratio was 0.13, whereas the corresponding values in case of hs-cTnT were 95.6 % (95 % CI 85.2–99.5), 61.3 % (95 % CI 49.5–72.6), 59.7 %, 95.8 %, 2.47 and 0.07 by taking cut off as >14 pg/ml. The area under the ROC curves (AUC) of MPO and hscTnT at 0–6 h were 0.971 (95 % CI 0.92–0.99, P < 0.001) and 0.797 (95 % CI 0.71–0.86, P < 0.001) respectively. The logistic model combining the two markers yielded sensitivity, specificity, positive predictive value and negative predictive value of 95.7, 97.3, 98.2 and 93.7 % respectively. It was concluded that MPO and hs-cTnT may be useful tools for risk stratification of ACS and can be used together with better accuracy in the early diagnosis of ACS.     

Asymptotic stability in a flexible-joint robot with model uncertainty and multiple time delays in feedback

This study considers the stability problem of a flexible-joint robot in case time delays are involved in the feedback loop. We assume in our analysis that the controller uses only position measurements. The single and multiple time-delay cases, are considered. By using some useful structural properties of the robot model, sufficient conditions for asymptotic (exponential) stability of the system under consideration have been established. An estimate to the system rate of convergence is given and a procedure for evaluating the region of attraction, is given.     

Therapy in Parkinson’s disease: Some recent developments

Even though research is going on throughout the world, it is clear that at the present time there is really no cure for Parkinson’s disease. Treatment with drugs, with physiotherapy can slow down the progress of this disease. Treatment through brain grafting or reparative therapy using different nerve growth factors may be the only alternative for this disease. Researchers are still hoping that the newly discovered substances could one day help doctors treat this invincible disease and possibly cure it also.     

The (amorphous) anatomy of an invention: the case of magnetic resonance imaging (MRI)

The priority dispute between Raymond Damadian and Paul Lauterbur over the 'invention' of magnetic resonance imaging (MRI) has attracted the attention of social and natural scientists for more than 30 years. In this paper, I have used this priority dispute to analyze the complex socio-epistemic processes through which a claim for an invention is made and strengthened. I argue that a tension exists because techno-scientific practices are embedded within a particular disciplinary regime of authorship: even though techno-scientific practices occur through distributed cognition and are contingent upon particular socio-epistemic contexts, a claim for an invention requires assigning authorship to a particular person, company, or institution in order to clearly define the origin and the novelty of that particular techno-scientific event. Nevertheless, the outcomes of socio-epistemic practices for making and strengthening priority claims are shifting, open-ended, and contingent upon particular socio-epistemic contexts.     

Great experiments in physics

In 1965, Arno Penzias and Robert Wilson of Bell Telephone Laboratories in USA discovered weak microwave radiation coming from all directions which was soon realised to be a relic from a hot dense early phase of our Universe—the ‘big bang’. This article focuses on the key experimental techniques and innovations which made this momentous—and accidental!—discovery possible. Amit Roy is at the Nuclear Science Centre, New Delhi, building a superconducting linac booster for the pelletron accelerator. He spent over two decades at the Tata Institute of Fundamental Research, Mumbai investigating nuclei using accelerators and probing symmetries in physics. His hobbies are books and music.     

Low cost demonstration experiment Lorentz force: Change in path of charged particles in magnetic field

The path of charged particles is affected when they enter a magnetic field. This change of path largely depends on the angle between the applied magnetic field and the direction of motion of the charged particle (and its velocity) entering the magnetic field. This is demonstrated by means of a simple, low-cost experiment. A high voltage is used to ionize the air between a spark gap. The flow of charged particles between the spark gap is altered by applying a magnetic field from a rare earth permanent magnet having surface magnetic field induction of 0.12 T.     

Service Strategies for Higher Educational Institutions Based on Student Segmentation

Over the last decade, higher education institutions in the U.S. have faced increased competition and expenditures coupled with declines in financial support. Furthermore, they often have been forced to cater to the needs of an increasingly diverse group of students and must design service strategies based on the unique needs of each group. This paper advocates the use of target marketing principles to effectively and efficiently allocate resources among the various groups. Student registration data from a large, urban, public university, which is routinely available at little cost, is used to identify five student segments. These segments include traditional students, non-traditional students, a sizable international student segment, a graduating segment, and a group of transferees. The unique needs of each segment are identified and appropriate service strategies are formulated for each segment. The diversity of the segments establish the utility of using target marketing principles for designing service strategies and the viability of using registration database for such a purpose.