Statistical Mechanics of DNA Rupture: Theory and Simulations

We study the effects of the shear force on the rupture mechanism on a double stranded DNA. Motivated by recent experiments, we perform the atomistic simulations with explicit solvent to obtain the distributions of extension in hydrogen and covalent bonds below the rupture force. We obtain a significant difference between the atomistic simulations and the existing results in the iterature based on the coarse-grained models (theory and simulations). We discuss the possible reasons and improve the coarse-grained model by incorporating the consequences of semi-microscopic details of the nucleotides in its description. The distributions obtained by the modified model (simulations and theoretical) are qualitatively similar to the one obtained using atomistic simulations.Comment: 18 pages, 9 figures. Accepted in J. Chem. Phys. (2013). arXiv admin note: text overlap with arXiv:1104.305

Effect of La Doping on Microstructure and Critical Current Density of MgB2

In the present study, La-doped MgB_2 superconductors with different doping level (Mg1-xLaxB2; x=0.00, 0.01, 0.03 & 0.05) have been synthesized by solid-state reaction route at ambient pressure. Effect of La doping have been investigated in relation to microstructural characteristics and superconducting properties, particularly intragrain critical current density (Jc). The microstructural characteristics of the as synthesized Mg(La)B2 compounds were studied employing transmission electron microscopic (TEM) technique. The TEM investigations reveal inclusion of LaB6 nanoparticles within the MgB2 grains which provide effective flux pinning centres. The evaluation of intragrain Jc through magnetic measurements on the fine powdered version of the as synthesized samples reveal that Jc of the samples change significantly with the doping level. The optimum result on Jc is obtained for Mg0.97La0.03B2 at 5K, the Jc reaches ~1.4x107A/cm2 in self field, ~2.1 x 106A/cm2 at 1T, ~2.5 x 105A/cm2 at 2.5T and ~1.8 x 104 A/cm2 at 4.5T. The highest value of intragrain Jc in Mg0.97La0.03B2 superconductor has been attributed to the inclusion of LaB6 nanoparticles which are capable of providing effective flux pinning centres

Respiratory behavior of turning stage mature tomato (Solanum lycopersicum L.) under closed system at different temperature

The respiration rate and respiratory quotient of mature tomato (Solanum lycopersicum L. cv. ‘Himsona’) fruits harvested at the turning stage were determined under closed system at 5, 10, 15, 20, 25 and 35 °C (ambient) temperatures. The rate of respiration was higher at the start of the experiment and gradually declined as the storage period prolonged, before becoming almost constant. The steady-state respiration rate for CO2 evolution were observed to be 14.35, 15.04,19.95, 21.7 and 20.3 ml/kg-h at 10 °C, 15 °C, 20 °C, 25 °C and 35 °C, respectively. The RQ values for tomato varied from 0.55 to 1.10 with time under the experimental conditions. The respiration rate at steady state based on carbon dioxide evolution and oxygen consumption in closed condition decreased by about 46 % and 73 %, respectively relative to initial respiration rate values at normal air atmosphere. The results suggest that the respiration rate of tomato increased with temperature and decrease with storage time

Clinical profile of Cholera cases in Yavatmal District, Maharashtra

Introduction- Outbreak of Cholera still remains major public health problem in most of the developing countries including India. Clinical profile of cholera was studied in Patients attending tertiary care hospital situated in tribal area of Central India, Yavatmal. Methods: Type of study- Descriptive cross-sectional. Study Duration - 2 months (June - July 2012). Study setting- Inpatient Department of S. V. N. Govt. Medical College, Yavatmal (Maharashtra). Study subjects- All cholera patients attending S. V. N. Govt. Medical College Yavatmal (Maharashtra) with the complaints of acute watery diarrhoea. Study variables- Detailed clinical profile of these cases was noted along with other relevant environmental history. Results-Out of a total 377 cases of acute watery diarrhoea, 13 isolates were positive for cholera. All the isolates were V. cholera 01 biotype El Tor serotype Ogawa.  46.2%   of cases were below 5 years of age, the two youngest children being 1.5 years old. Both the sexes were equally affected. 61.5% cases had duration of diarrhoea more than 24 hours. Overall living and hygienic conditions of all the patients were poor. However all patients responded to intravenous fluids, oral rehydration and antibiotics (Doxycycline) within 24-48 hours without any mortality. Interpretation & conclusions: This study reflects the cases infected with 01 El Tor Ogawa  with severe and critical clinical features in Yavatmal district causing high morbidity in the form of severe dehydration and peripheral circulatory collapse which requires early, correct diagnosis and prompt treatment