Oblique propagation of nonlinear ion-acoustic cnoidal waves in magnetized electron–positron–ion plasmas with nonextensive electrons

Theoretical investigation of nonlinear electrostatic ion-acoustic cnoidal waves(IACWs) is presented in magnetized electron–positron–ion plasma with nonextensive electrons and Maxwellian positrons. Using reductive perturbation technique, Korteweg–de Vries equation is derived and its cnoidal wave solution is analyzed. For given plasma parameters, our model supports only positive potential(compressive) IACW structures. The effect of relevant plasma parameters(viz., nonextensive parameter q, positron concentration p, temperature ratio σ,obliqueness l3) on the characteristics of IACWs is discussed in detail.

MicroPath-A pathway-based pipeline for the comparison of multiple gene expression profiles to identify common biological signatures

High throughput gene expression analysis is swiftly becoming the focal point for deciphering molecular mechanisms underlying various dif-ferent biological questions. Testament to this is the fact that vast volumes of expression profiles are being generated rapidly by scientists worldwide and subsequently stored in publicly available data repositories such as ArrayEx-press and the Gene Expression Omnibus (GEO). Such wealth of biological data has motivated biologists to compare expression profiles gen-erated from biologically-related microarray ex-periments in order to unravel biological mecha-nisms underlying various states of diseases. However, without the availability of appropriate software and tools, they are compelled to use manual or labour-intensive methods of com-parisons. A scrutiny of current literature makes it apparent that there is a soaring need for such bioinformatics tools that cater for the multiple analyses of expression profiles. In order to contribute towards this need, we have developed an efficient software pipeline for the analysis of multiple gene expression data-sets, called Micropath, which implements three principal functions;1) it searches for common genes amongst n number of datasets using a number crunching method of comparison as well as applying the principle of permutations and combinations in the form of a search strat-egy, 2) it extracts gene expression patterns both graphically and statistically, and 3) it streams co-expressed genes to all molecular pathways belonging to KEGG in a live fashion. We sub-jected MicroPath to several expression datasets generated from our tolerance-related in-house microarray experiments as well as published data and identified a set of 31 candidate genes that were found to be co-expressed across all interesting datasets. Pathway analysis revealed their putative roles in regulating immune toler-ance. MicroPath is freely available to download from: www.1066technologies.co.uk/micropath.

Label-free colorimetric nanosensor with improved sensitivity for Pb^2+ in water by using a truncated 8-17 DNAzyme

Water pollution accidents, such as the Flint water crisis in the United States, caused by lead contamination have raised concern on the safety of drinking water distribution systems. Thus, the routine monitoring of lead in water is highly required and demands efficient, sensitive, cost-effective, and reliable lead detection methods. This study reports a label-free colorimetric nanosensor that uses unmodified gold nanoparticles (AuNPs) as indicators to enable rapid and ultra-sensitive detection of lead in environmental water. The 8-17 DNAzyme was truncated in this study to facilitate the detachment of single-stranded DNA fragments after substrate cleavage in the presence of Pb「. The detached fragments were adsorbed over AuNPs and protected against salt concentration-induced aggregation. Accordingly, high Pb^2+ would result in rapid color change from blue to pink. The established sensing principle achieved a sensitive limit of detection of 0.2×10^-9mol/L Pb^2+. with a linear working range of two orders of magnitude from 0.5×10^-9mol/L to 5×10^-9mol/L. The selectivity of the nanosensor was demonstrated by evaluating the interfering metal ions. The developed nanosensor can serve as a substitute for the rapid analysis and monitoring of trace lead levels under the drinking water distribution system and even other environmental water samples.

Subversion of cellular autophagy during virus infection:Insights from hepatitis B and hepatitis C viruses

Autophagy is a self-eating process,in which the damaged or excessed cell organelles and misfolded protein aggregates are removed from the cellular microenvironment.Autophagy is generally thought of as a pro-survival mechanism which is not only important for balancing energy supply at times of nutrient deprivation but also in the removal of various stress stimuli to ensure homeostasis.In addition to the target materials of“self”origin,autophagy can also eliminate intracellular pathogens and acts as a defense mechanism to curb infections.In addition,autophagy is linked to the host cell's innate immune response.However,viruses have evolved various strategies to manipulate and overtake host cell machinery to establish productive replication and maintain infectious process.In fact,replication of many viruses has been found to be autophagy-dependent and suppression of autophagy can potentially affect the viral replication.Thus,autophagy can either serve as an anti-viral defense mechanism or a pro-viral process that supports viral replication.Hepatitis B virus(HBV)and hepatitis C virus(HCV)are known to co-opt cellular autophagy process as a pro-viral tool.Both viruses also induce mitophagy,which contributes to the establishment of chronic hepatitis.This review focuses on the roles of autophagy and mitophagy in the chronic liver disease pathogenesis associated with HBV and HCV infections.

Electron acoustic solitary waves in unmagnetized nonthermal plasmas

Electron acoustic(EA)solitary waves(SWs)are studied in an unmagnetized plasma consisting of hot electrons(following Cairns-Tsalli distribution),inertial cold electrons,and stationary ions.By employing a reductive perturbation technique(RPT),the nonlinear Korteweg–de Vries(KdV)equation is derived and its SW solution is analyzed.Here,the effects of plasma parameters such as the nonextensivity parameter(q),the nonthermality of electrons(α),and the cold-to-hot electron density ratio(β)are investigated.