Chemical Exfoliation as a Controlled Route to Enhance the Anodic Performance of COF in LIB

A covalent organic framework (COF), built from light atoms with a graphitic structure, could be an excellent anodic candidate for lightweight batteries, which can be of use in portable devices. But to replace the commercial graphite anode, they need more Li‐interactive sites/unit‐cell and all such sites should be made to participate. The compromise made in the volumetric density to gain the gravimetric advantage should be minimal. Exfoliation enhances surface/functional group accessibility yielding high capacity and rapid charge storage. A chemical strategy for simultaneous exfoliation and increase of Li‐loving active‐pockets can deliver a lightweight Li‐ion battery (LIB). Here, anthracene‐based COFs are chemically exfoliated into few‐layer‐thick nanosheets using maleic anhydride as a functionalizing exfoliation agent. It not only exfoliates but also introduces multiple Li‐interactive carbonyl groups, leading to a loading of 30 Li/unit‐cell (vs one Li per C₆). The exfoliation enhances the specific capacity by ≈4 times (200–790 mAh g^?1 @100 mA g^?1). A realistic full‐cell, made using the exfoliated COF against a LiCoO₂ cathode, delivers a specific capacity of 220 mAh g^?1 over 200 cycles. The observed capacity stands highest among all organic polymers. For the first report of a COF derived full‐cell LIB, this is a windfall.     

Oxylipin biosynthesis reinforces cellular senescence and allows detection of senolysis

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Simplified production technology of blue green alga Spirulina platensis for feed applications in India

Summary A rural oriented methodology for the production of the blue green alga Spirulina platensis has been developed and practically evaluated on pilot plant scale (45 m²). The system suggested is almost free of electrical inputs or capital intensive equipment and designed to use maximal manpower. A production rate of 3 kg of dry algae per week can be achieved using 45 m² area.     

Selenium-dependent glutathione peroxidase modules encoded by RNA viruses

Glutathione peroxidase (GPx) is the prototypical eukaryotic selenoprotein, with the rare amino acid selenocysteine (Sec) at the enzyme active site, encoded by the UGA codon in RNA. A DNA virus,Molluscum contagiosum, has now been shown to encode a functional selenium-dependent GPx enzyme. Using modifications of conventional sequence database searching techniques to locate potential viral GPx modules, combined with structurally guided comparative sequence analysis, we provide compelling evidence that Se-dependent GPx modules are encoded in a number of RNA viruses, including potentially serious human pathogens like HIV-1 and hepatitis C virus, coxsackievirus B3, HIV-2, and measles virus. Analysis of the sequences of multiple viral isolates reveals conservation of the putative GPx-related features, at least within viral subtypes or genotypes, supporting the hypothesis that these are functional GPx modules.