Green synthesis of selenium nanoparticles (SeNPs) was achieved by a simple biological procedure using the reducing power of fenugreek seed extract. This method is capable of producing SeNPs in a size range of about 50-150 nm, under ambient conditions. The synthesized nanoparticles can be separated easily from the aqueous sols by a high-speed centrifuge. These selenium nanoparticles were characterized by UV-Vis spectroscopy, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and elemental analysis by X-ray fluorescence spectrometer (XRF). Nanocrystalline SeNPs were obtained without post-annealing treatment. FTIR spectrum confirms the presence of various functional groups in the plant extract, which may possibly influence the reduction process and stabilization of nanoparticles. The cytotoxicity of SeNPs was assayed against human breast-cancer cells (MCF-7). It was found that SeNPs are able to inhibit the cell growth by dose-dependent manner. In addition, combination of SeNPs and doxorubicin shows better anticancer effect than individual treatments.

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A systematic study to quantify the effects of specific microstructural features on the spall behavior of 99.999 pct copper has revealed a strong dependence of the failure processes on length scale. Shock loading experiments with Cu flyer plates at velocities ranging from 300 to 2000 m/s (or impact pressures from 5 to 45 GPa) using a 35-mm single/two-stage light gas gun revealed that single crystals exhibit a higher spallation resistance than fine-grained polycrystals and internally oxidized single crystals. However, in contrast to previously reported results, the fine-grained (ϳ8-m) polycrystalline samples exhibit lower damage resistance than the coarse-grained (50-and 133-m) samples. These observations have been analyzed in the context of the length scale inherent in each of these microstructures, and modeled using an analytical model developed recently.

Protein–peptide interactions, where one partner is a globular protein (domain) and the other is a flexible linear peptide, are key components of cellular processes predominantly in signaling and regulatory networks, hence are prime targets for drug design. To derive the details of the protein–peptide interaction mechanism is often a cumbersome task, though it can be made easier with the availability of specific databases and tools. The Peptide Binding Protein Database (PepBind) is a curated and searchable repository of the structures, sequences and experimental observations of 3100 protein–peptide complexes. The web interface contains a computational tool, protein inter-chain interaction (PICI), for computing several types of weak or strong interactions at the protein–peptide interaction interface and visualizing the identified interactions between residues in Jmol viewer. This initial database release focuses on providing protein–peptide interface information along with structure and sequence information for protein–peptide complexes deposited in the Protein Data Bank (PDB). Structures in PepBind are classified based on their cellular activity. More than 40% of the structures in the database are found to be involved in different regulatory pathways and nearly 20% in the immune system. These data indicate the importance of protein–peptide complexes in the regulation of cellular processes. PepBind is freely accessible at http://pepbind.bicpu.edu.in/.

Regiospecific formation of carbanions from a set of geometrical (cis and trans isomers) and five different sets of positional isomers (ortho, meta and para isomers) of aromatic carboxylic acids is reported under negative electrospray ionisation conditions by decarboxylation of the carboxylate anions. The structures of decarboxylated anions, [(M-H)-CO(2)](-), are studied by ion-molecule reactions with carbon dioxide in the collision cell of a triple quadrupole mass spectrometer. The [(M-H)-CO(2)](-) ions generated from the trans and meta/para isomers react with CO(2) to produce product ions corresponding to the addition of one CO(2), which confirms the survival of the [(M-H)-CO(2)](-) ions as carbanions. On the other hand, the [(M-H)-CO(2)](-) ions generated from cis and ortho isomers failed to react with CO(2) due to rapid isomerisation of the initially generated carbanion to a aromatic carboxylate/oxide anion, which is unreactive with CO(2), through a facile intramolecular proton transfer from the proton-containing substituent to the carbanion site. When the experiments were performed at high desolvation temperatures (300 degrees C), instead of 100 degrees C, the relative abundance of [(M-H)-CO(2)](-) ions and the corresponding CO(2) adduct in ion-molecule reaction experiments increased significantly due to minimisation of proton exchange. Quantum chemical calculations on some of the generated isomeric carbanions and their isomerised products due to proton transfer support the selective stability of carbanions.

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Additive manufacturing (AM) is enabling the fabrication of materials with engineered lattice structures at the micron scale. These mesoscopic structures fall between the length scale associated with the organization of atoms and the scale at which macroscopic structures are constructed. Dynamic compression experiments were performed to study the emergence of behavior owing to the lattice periodicity in AM materials on length scales that approach a single unit cell. For the lattice structures, both bend and stretch dominated, elastic deflection of the structure was observed ahead of the compaction of the lattice, while no elastic deformation was observed to precede the compaction in a stochastic, random structure. The material showed lattice characteristics in the elastic response of the material, while the compaction was consistent with a model for compression of porous media. The experimental observations made on arrays of 4 × 4 × 6 lattice unit cells show excellent agreement with elastic wave velocity calculations for an infinite periodic lattice, as determined by Bloch wave analysis, and finite element simulations.

BCR-ABL tyrosine kinase plays a major role in the pathogenesis of chronic myeloid leukemia (CML) and is a proven target for drug development. Currently available drugs in the market are effective against CML; however, side-effects and drug-resistant mutations in BCR-ABL limit their full potential. Using high throughput virtual screening approach, we have screened several small molecule databases and docked against wild-type and drug resistant T315I mutant BCR-ABL. Drugs that are currently available, such as imatinib and ponatinib, were also docked against BCR-ABL protein to set a cutoff value for our screening. Selected lead compounds were further evaluated for chemical reactivity employing density functional theory approach, all selected ligands shows HLG value > 0.09900 and the binding free energy between protein-ligand complex interactions obtained was rescored using MM-GBSA. The selected compounds showed least ΔG score −71.53 KJ/mol to maximum −126.71 KJ/mol in both wild type and drug resistant T315I mutant BCR-ABL. Following which, the stability of the docking complexes were evaluated by molecular dynamics simulation (MD) using GROMACS4.5.5. Results uncovered seven lead molecules, designated with Drug-Bank and PubChem ids as DB07107, DB06977, ST013616, DB04200, ST007180 ST019342, and DB01172, which shows docking scores higher than imatinib and ponatinib.