Heat shock response in mulberry silkworm races with different thermotolerances

The thermal sensitivity and heat shock response of the different races of the mulberry silkworm Bombyx mori have been analysed. The multivoltine race, strains C. Nichi and Pure Mysore showed better survival rates than the bivoltine race, strain NB4D2 exposed to 41 degrees C and above. In general, the fifth instar larvae and the pupae exhibited maximum tolerance compared to the early larval instars, adult moths or the eggs. Exposure up to 39 degrees C for 1 or 2 h was tolerated equally whereas temperatures above 43 degrees C proved to be lethal for all. Treatment of larvae at 41 degrees C for Ih resulted in a variety of physiological alterations including increased heart beat rates, differential haemocyte counts, enlargement of granulocytes and the presence of additional protein species in the tissues and haemolymph. The appearance of a 93 kDa protein in the haemolymph, fat bodies and cuticle, following the heat shocking of larvae in vivo was a characteristic feature in all the three strains examined although the kinetics of their appearance itself was different. In haemolymph, the protein appeared immediately in response to heat shock in C. Nichi reaching the maximal levels in 2-4 h whereas its presence was noticeable only after 2-4 h recovery time in Pure Mysore and bivoltine races. The fat body from both C. Nichi and NB4D2 showed the presence of 93 kDa, 89 kDa and 70 kDa proteins on heat shock. The haemocytes, on the other hand, expressed only a 70 kDa protein consequent to heat shock. The 93 kDa protein in the haemolymph, therefore could have arisen from some other tissue, possibly the fat body. The 93 kDa protein was detected after heat shock in pupae and adult moths as well, although the presence of an additional (56 kDa) protein was also apparent in the adults. The presence of 46 kDa and 28 kDa bands in addition to the 93 kDa band in the cuticular proteins immediately following heat shock was clearly discernible. The 70 kDa band did not show much changes in the cuticular proteins on heat shock. In contrast to the changes in protein profiles seen in tissues and haemolymph following heat shock in vivo, the heat treatment of isolated fat body or haemolymph in vitro resulted in protein degradation.

Organometallic chemistry of diphosphazanes. Part IX: Syntheses and spectroscopic studies of molybdenum and tungsten tetracarbonyl complexes of unsymmetrical diphosphazanes

The unsymmetrical diphosphazanes X2PN(Pr(i))PYY'(1a-1h) {X = Ph, YY' = O2 C6H4 (1a) or YY' = O2C12H8 (1b); X = Ph, Y = Ph, Y' = OC6H4Me-4 (1c), OC6H4Br-4 (1d), OC6H3Me2-3,5 (1e), OC5H4N-2 (1f), N2C3HMe2-3,5 (1g) or Cl (1h)} react with [M(CO)4(NHC5H10)2] (M = Mo, W) to yield the cis-chelate complexes [M(CO)4{X2PN(Pr(i)) PYY'}] {M = Mo (2a-2h); M = W (3-f,3-g)}. These complexes have been characterized by H-1, P-31 and C-13 NMR and IR spectroscopic studies.

C:N ratio of Sediments in a sewage fed Urban Lake

C:N ratio of lake sediments provide valuable information about the source and proportions of terrestrial, phytogenic and phycogenic carbon and nitrogen. This study has been carried out in Varthur lake which is receiving sewage since many decades apart from large scale land cover changes. C:N profile of the surficial sediment layer collected in the rainy and the dry seasons revealed higher C:N values[43] due to the accumulation of autochthonous organic material mostly at the deeper portions of the lake. This also highlights N limitation in the sludge either due to uptake by micro and macro-biota or rapid volatilization, denitrification and possible leaching in water. Organic Carbon was lower towards the inlets and higher near the deeper zones. This pattern of Organic C deposition was aided by gusty winds and high flow conditions together with impacts by the land use land cover changes in the watershed. Spatial variability of C:N in surficial sediments is significant compared to its seasonal variability. This communication provides an insight to the pattern in which nutrients are distributed in the sludge/sediment and its variation across seasons and space impacted by the biotic process accompanied by the hydrodynamic changes in the lake.

Advances in the Mathematical Modelling of Hepatitis C Virus Dynamics

Mathematical models have provided key insights into the pathogenesis of hepatitis C virus (HCV) in vivo, suggested predominant mechanism(s) of drug action, explained confounding patterns of viral load changes in HCV infected patients undergoing therapy, and presented a framework for therapy optimization. In this article, I present an overview of the major advances in the mathematical modeling of HCV dynamics.

Fast and accurate quantification using Genetic Algorithm optimized H-1-C-13 refocused constant-time INEPT

Using Genetic Algorithm, a global optimization method inspired by nature's evolutionary process, we have improved the quantitative refocused constant-time INEPT experiment (Q-INEPT-CT) of Makela et al. (JMR 204 (2010) 124-130) with various optimization constraints. The improved `average polarization transfer' and `min-max difference' of new delay sets effectively reduces the experimental time by a factor of two (compared with Q-INEPT-CT, Makela et al.) without compromising on accuracy. We also discuss a quantitative spectral editing technique based on average polarization transfer. (C) 2013 Elsevier Inc. All rights reserved.

The X-C center dot center dot center dot pi (X = F, Cl, Br, CN) Carbon Bond

High-level ab initio calculations have been used to study the interactions between the CH3 group of CH3X (X = F, Cl, Br, CN) molecules and pi-electrons. These interactions are important because of the abundance of both the CH3 groups and pi-electrons in biological systems. Complexes between C2H4/C2H2 and CH3X molecules have been used as model systems. Various theoretical methods such as atoms in molecules theory, reduced density gradient analysis, and natural bond orbital analysis have been used to discern these interactions. These analyses show that the interaction of the p-electrons with the CH3X molecules leads to the formation of X-C...p carbon bonds. Similar complexes with other tetrel molecules, SiH3X and GeH3X, have also been considered.