Indian Association for the Cultivation of Science

About: Indian Association for the Cultivation of Science is a education organization based out in Kolkata, India. It is known for research contribution in the topics: Excited state & Catalysis. The organization has 3867 authors who have published 10457 publications receiving 220098 citations.

Effect of alkali treated jute fibres on composite properties

Abstract: Jute fibres were subjected to a 5% alkali (NaOH) solution treatment for 0, 2, 4, 6 and 8 h at 30°C. An improvement in the crystallinity in the jute fibres increased its modulus by 12%, 68% and 79% after 4, 6 and 8 h of treatment respectively. The tenacity of the fibres improved by 46% after 6 and 8 h treatment and the % breaking strain was reduced by 23% after 8 h treatment. For the 35% composites with 4 h treated fibres, the flexural strength improved from 199.1 MPa to 238.9 MPa by 20%, modulus improved from 11.89 GPa to 14.69 GPa by 23% and laminar shear strength increased from 0.238 MPa to 0.2834 MPa by 19%. On plotting the different values of slopes obtained from the rates of improvement of the flexural strength and modulus, against the NaOH treatment time, two different failure modes were apparent before and after 4 h of treatment. In the first region between 0 and 4 h, fibre pull out was predominant whereas in the second region between 6 and 8 h, transverse fracture occurred with a minimum fibre pull out. This observation was well supported by the SEM investigations of the fracture surfaces.

Circ2Traits: a comprehensive database for circular RNA potentially associated with disease and traits.

Abstract: Circular RNAs are new players in regulation of post transcriptional gene expression. Animal genomes express many circular RNAs from diverse genomic locations. A recent study has validated a fairly large number of circular RNAs in human, mouse and nematode. Circular RNAs play a crucial role in fine tuning the level of miRNA mediated regulation of gene expression by sequestering the miRNAs. Their interaction with disease associated miRNAs indicates that circular RNAs are important for disease regulation. We studied the potential association of circular RNAs (circRNA) with human diseases in two different ways. First, the interactions of circRNAs with disease associated miRNAs were identified, following which the likelihood of a circRNA being associated with a disease was calculated. For the miRNAs associated with individual diseases, we constructed a network of predicted interactions between the miRNAs and protein coding, long noncoding and circular RNA genes. We carried out gene ontology (GO) enrichment analysis on the set of protein coding genes in the miRNA- circRNA interactome of individual diseases to check the enrichment of genes associated with particular biological processes. Second, disease associated SNPs were mapped on circRNA loci, and Argonaute (Ago) interaction sites on circular RNAs were identified. We compiled a database of disease-circRNA association in Circ2Traits ( http://gyanxet-beta.com/circdb/ ), the first comprehensive knowledgebase of potential association of circular RNAs with diseases in human.

Supramolecular assemblies by charge-transfer interactions between donor and acceptor chromophores.

Abstract: We have collated various supramolecular designs that utilize organic donor–acceptor CT complexation to generate noncovalently co-assembled structures including fibrillar gels, micelles, vesicles, nanotubes, foldamers, conformationally restricted macromolecules, and liquid crystalline phases. Possibly inspired by nature, chemists have extensively used hydrogen bonding as a tool for supramolecular assemblies of a diverse range of abiotic building blocks. As a structural motif, CT complexes can be compared to hydrogen-bonded complexes in its directional nature and complementarities. Additional advantages of CT interactions include wider solvent tolerance and easy spectroscopic probing. Nevertheless the major limitation is their low association constant. This article shows different strategies have evolved over the years to overcome this drawback by reinforcing the CT interactions with auxiliary noncovalent forces without hampering the alternate stacking mode. Emerging reports on promising CT complexes in organic electronics are intimately related to various supramolecular designs that one can postulate based on donor–acceptor CT interactions.

Immobilization of bio-macromolecules on self-assembled monolayers: methods and sensor applications

Abstract: Attachment of biomolecules on gold, silicon or glass surfaces has direct implications for the development of novel biosensors in the context of nanoscale detection of pathogens and other metabolites related to issues of human health. In this critical review, we have highlighted the current developments in various techniques of immobilization of biomolecules, specifically biological macromolecules on surfaces through the modification of a functional self-assembled monolayer. The utility of such immobilized biomolecules in the area of biosensing in nanoscale has been surveyed. Merits and demerits of some of the methods with reference to sensitivity of detection and practical use have been discussed (221 references).

Slow dynamics of constrained water in complex geometries

Abstract: Although water is often hailed as the lubricant of life, a detailed understanding of its role in many chemical and biological processes still eludes us. In many natural systems, water is confined in an environment where its free movement is restricted and its three-dimensional hydrogen-bonded network is disrupted. Very recently, several groups applied ultrafast laser spectroscopy to study the dynamics of the constrained water molecules. It is observed that the dynamic behavior of the confined water molecules is markedly different from that of the ordinary water molecules. The most striking result is the bimodal response of confined water, with one bulk water-like subpicosecond component and a much slower component in a time scale of hundreds or thousands of picoseconds. This slow second component constitutes 10−30% of the total response and is crucial in the understanding of the role of water in complex chemical and biological processes. The origin of the slow component has been a subject of intense recen...