Recent progress of precious-metal-free electrocatalysts for efficient water oxidation in acidic media

The realization of efficient oxygen evolution reaction(OER) is critical to the development of multiple sustainable energy conversion and storage technologies, especially hydrogen production via water electrolysis. To achieve the massive application of hydrogen energy and mass-scale hydrogen production from water splitting drives the pursuit of competent precious-metal-free electrocatalysts in acidic media, where the hydrogen evolution reaction(HER) is more facilitated. However, the development of high-efficient and acid-stable OER electrocatalysts, which are robust to function stably at high oxidation potentials in the acidic electrolyte, remains a great challenge. This article contributes a focused, perceptive review of the up-to-date approaches toward this emerging research field. The OER reaction mechanism and fundamental requirements for oxygen evolution electrocatalysts in acid are introduced. Then the progress and new discoveries of precious-metal-free active materials and design concepts with regard to the improvement of the intrinsic OER activity are discussed. Finally, the existing scientific challenges and the outlooks for future research directions to the fabrication of emerging, earth-abundant OER electrocatalysts in acid are pointed out.

Alteration in the expression of microRNA-21 regulated target genes:Role in breast cancer

Breast cancer,also recognized as the principal cause of cancer-related deaths among women,is the second most familiar and prevalent form of cancer.New diagnostic and prognostic biomarkers that are highly specific are urgently needed for its early prognosis.MicroRNAs(miRNAs),a class of non-coding RNAs,are known to control the biological processes involving transcription,post-transcriptional and covalent modifications,splicing,translation,cell differentiation,proliferation,apoptosis,cancer progression,and invasion.Any dysregulation in miRNA expression,demonstrating their oncogenic and tumor-suppressive functions,contributes to cancer progression.MicroRNA-21(miR-21),an‘onco-miR’in breast cancer,is involved in tumor progression and metastasis by suppressing the activity of the target gene via its interaction with the 3’UTR of the target gene.The upregulation of miR-21 is observed in many instances of breast cancer.Our review aims to summarize the current understanding of miR-21 in the regulation of important cellular functions via regulation of its target genes.We discuss its biosynthesis,oncogenic function in breast cancer,and different methods used for its detection.This will increase the current understanding of the role of miR-21 in breast cancer tumorigenesis,which will offer a perception of using miR-21 as an early detection molecular prognostic and diagnostic biomarker and as a therapeutic target in breast cancer care.

Antimicrobial Materials: New Strategies to Tackle Various Pandemics

Coronaviruses are responsible for a developing budgetary,human and fatality trouble,as the causative factor of infections,for example,severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).It has been well recognized that SARS-CoV-2 may survive under severe atmosphere circumstances.Hence,efficient containment approaches,for example,sanitizing,are crucial.Commonly,living compounds contribute a substance of chemical heterogeneity,with antiviral movement,and therefore can have efficacy as therapeutic tools toward coronavirus diseases.Here,in this review article,we have described the antimicrobialbased materials,which can be used to inhibit the spreading of the COVID-19.We have categorized these materials in three sections;(i)antimicrobial wall paint,(ii)antimicrobial papers and(iii)antimicrobial materials surface coating to be utilized as the antimicrobial-based materials for controlling the COVID-19.In the last section,we have given the concluding remarks with prospects in this area.

Biorenewable materials for water remediation: The central role of cellulose in achieving sustainability

As the population increases and manufacturing grows,greenhouse gas and other harmful emissions increase.Contaminated with chemicals such as dyes,pesticides,pharmaceuticals,oil,heavy metals or radionuclides,wastewater purification has become an urgent issue.Various technologies exist that can remove these contaminants from wastewater sources,but they often demand high energy and/or high cost,and in some cases produce contaminant laden sludge that requires safe disposal.The need for methods which are less capital intensive,less operationally costly and more environmentally friendly is suggested.Cellulose-based materials have emerged as promising candidates for wastewater treatment due to their renewability,low cost,biodegradability,hydrophilicity,and antimicrobial property.In this review article,we focussed on developing sustainable and biodegradable cellulose-based materials for wastewater treatment.This article deals with cellulose-based materials’scope and their conversion into valuable products like hydrogel,aerogel,cellulose composites,and nanocellulose.The cellulose-based materials have no harmful environmental impact and are plentiful.The modified cellulose-based materials applying as membrane,adsorbent,sorbent,and beads to purify the wastewater were discussed.Finally,the challenges and future prospects of cellulose-based materials for wastewater treatment were considered,emphasizing their potential to be sustainable and eco-friendly alternatives to traditional materials used in wastewater treatment.

Cellulose-based smart materials:Novel synthesis techniques,properties,and applications in energy storage and conversion devices

There has been a significant scope toward the cutting-edge in-vestigations in hierarchical carbon nanostructured electrodes originating from cellulosic materials,such as cellulose nanofibers,available from natural cellulose and bacterial cellulose.Elements of energy storage systems(ESSs)are typically established upon inorganic/metal mixtures,carbonaceous implications,and petroleum-derived hydrocarbon chem-icals.However,these conventional substances may need help fulfilling the ever-increasing needs of ESSs.Nanocellulose has grown significantly as an impressive 1D element due to its natural availability,eco-friend-liness,recyclability,structural identity,simple transformation,and dimensional durability.Here,in this review article,we have discussed the role and overview of cellulose-based hydrogels in ESSs.Additionally,the extraction sources and solvents used for dissolution have been dis-cussed in detail.Finally,the properties(such as self-healing,trans-parency,strength and swelling behavior),and applications(such as flexible batteries,fuel cells,solar cells,flexible supercapacitors and carbon-based derived from cellulose)in energy storage devices and conclusion with existing challenges have been updated with recent findings.