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Here we present the field induced self-assembly of anisotropic colloidal particles whose shape resembles peanuts. Being made up of hematite core and silica shell, these particles align in a direction perpendicular to the applied external magnetic field. Using small-angle X-ray scattering with microradian resolution (μrad-SAXS) in sedimented samples, we have found that one can tune the self-assembled structures by changing the time of application of the external field. If the field is applied after the sedimentation, the self-assembled structure is a nematic one, while dipolar chains are formed if the field is applied during the sedimentation process. Interestingly, within each chain particles form a smectic phase with defects. Further, these aforementioned nematic and smectic phases are of oblate type in spite of the prolate shape of the individual particles. For dipolar chains, an unusual diffraction peak shape has been observed with highly anisotropic tails in the transverse direction (perpendicular to the external field). The peak shape can be rationalized by considering the fact that the dipolar chains can act as a building block aligned along the field direction to form a para-nematic phase.

An attempt is made in this paper to report how a supervised methodology has been adopted for the task of word sense disambiguation in Bangla with necessary modifications. At the initial stage, the Naïve Bayes probabilistic model that has been adopted as a baselinemethod for sense classification, yields moderate result with 81% accuracy when applied on a database of 19 (nineteen) most frequently used Bangla ambiguous words. On experimental basis, the baseline methodis modified with two extensions: (a) inclusion of lemmatization process into of the system, and (b) bootstrapping of the operational process. As a result, the level of accuracy of the method is slightly improved up to 84% accuracy, which is a positive signal for the whole process of disambiguation as it opens scope for further modification of the existing method for better result. The data sets that have been used for this experiment include the Bangla POS tagged corpus obtained from the Indian Languages Corpora Initiative, and the Bangla WordNet, an online sense inventory developed at the Indian Statistical Institute, Kolkata. The paper also reports about the challenges and pitfalls of the work that have been closely observed and addressed to achieve expected level of accuracy.

An anisotropic colloidal shape in combination with an externally tunable interaction potential results in a plethora of self-assembled structures with potential applications toward the fabrication of smart materials. Here we present our investigation on the influence of an external magnetic field on the self-assembly of hematite-silica core–shell prolate colloids for two aspect ratios ρ = 2.9 and 3.69. Our study shows a rather counterintuitive but interesting phenomenon, where prolate colloids self-assemble into oblate liquid crystalline (LC) phases. With increasing concentration, particles with smaller ρ reveal a sequence of LC phases involving para-nematic, nematic, smectic, and oriented glass phases. The occurrence of a smectic phase for colloidal ellipsoids has been neither predicted nor reported before. Quantitative shape analysis of the particles together with extensive computer simulations indicate that in addition to ρ, a subtle deviation from the ideal ellipsoidal shape dictates the formation of this unusual sequence of field-induced structures. Particles with ρ = 2.9 exhibit a hybrid shape containing features from both spherocylinders and ellipsoids, which make their self-assembly behavior richer than that observed for either of the “pure” shapes. The shape of the particles with higher ρ matches closely with the ideal ellipsoids, as a result their phase behavior follows the one expected for a “pure” ellipsoidal shape. Using anisotropic building blocks and external fields, our study demonstrates the ramifications of the subtle changes in the particle shape on the field-directed self-assembled structures with externally tunable properties.

Background:India is going through a major economic and epidemiological transition. With the adoption of a Western lifestyle, atherosclerotic cardiovascular disease (CVD) has emerged as the leading cause of death. India is currently the second most populous country with a population of 1.3 billion and two-thirds of this population are less than 35 years of age. As a result, India is facing major challenges in dealing with CVD.Purpose:This study was conducted to assess the level of health awareness of CVD in school-aged children (10 to 16 years) and to evaluate the effect of a brief educational intervention in enhancing the level of awareness with a goal of developing a school-based health education program.Methods:A school-based survey was conducted in Calcutta, India in August, 2018. This involved a pre-evaluation of CVD health awareness, a short presentation on CVD, and a post-evaluation of CVD health awareness.Results:The survey involved 2,564 students from 18 schools (11 girls’, 5 boys’, 2 coeducation). The mean age of participating students was 14.6 years, 72% were girls, 55% of the students were in the 9th grade, 38% were from 10thgrade, and the rest were from a combination of 8th,11th,and 12thgrades. After assessing students’ awareness in six domains with 20 multiple-choice questions, the mean pre-test score was 46.5 (SD ± 13.3) with a maximum score of 100, and the mean post-test score was 53.6 (SD ± 20.6) (p< 0.001).Conclusions:Awareness of CVD and its risk factors was inadequate among school-aged children in Calcutta. A school-based educational program may promote awareness of CVD and adoption of healthy lifestyle practices. The results of this study may help formulate a nationwide school health program to ameliorate the morbidity and mortality of CVD in India where it has emerged as a modern epidemic.