LncRNA ZFAS1 regulates cardiomyocyte differentiation of human embryonic stem cells

Background:Cardiomyocytes derived from human embryonic stem cells(hESCs)are regulated by complex and stringent gene networks during differentiation.Long non-coding RNAs(lncRNAs)exert critical epigenetic regulatory functions in multiple differentiation processes.However,the involvement of lncRNAs in the differentiation of hESCs into cardiomyocytes has not yet been fully elucidated.Here,we identified the key roles of ZFAS1(lncRNA zinc finger antisense 1)in the differentiation of cardiomyocytes from hESCs.Methods:A model of cardiomyocyte differentiation from stem cells was established using the monolayer differentiation method,and the number of beating hESCs-derived cardiomyocytes was calculated.Gene expression was analyzed by quantitative real-time PCR(qRTPCR).Immunofluorescence assays were performed to assess the expression of cardiac troponin T(cTnT)andα-actinin protein in cardiomyocytes.Results:qRT-PCR showed that ZFAS1 expression in the mesoderm was significantly higher than that in embryonic stem cells,cardiac progenitor cells,and cardiomyocytes.Knockdown of ZFAS1 inhibited cardiomyocyte differentiation from hESCs,which was characterized by reduced expression of the cardiac-specific markers cTnT,α-actinin,myosin heavy chain 6(MYH6),and myosin heavy chain 7(MYH7).In contrast,ZFAS1 overexpression remarkably increased the percentage of spontaneously beating cardiomyocytes.In terms of the mechanism,we found that ZFAS1 is an antisense lncRNA at the 5′end of the protein-coding gene ZNFX1.Knockdown of ZFAS1 could increase the mRNA expression level of ZNFX1.Furthermore,qRT-PCR demonstrated that the silencing of ZNFX1 led to an increase in cardiac-specific markers that predicted the promotion of cardiomyocyte differentiation.Conclusion:Altogether,these data suggest that lncRNA-ZFAS1 is required for cardiac differentiation by functionally inhibiting the expression of ZNFX1,which may provide a reference for the treatment of heart disease to a certain extent.

Advances in the production technology of hydrogen peroxide

This article mainly summarizes various aspects of hydrogen peroxide(H2O2)production through the anthraquinone route,including hydrogenation catalysts,working solution,regeneration technique,hydrogenation reactors,and environmental protection.The advances and breakthrough of SINOPEC in the production of H2O2 through the anthraquinone route is presented in this review,highlighting recent innovative technology on these aspects developed independently.The technical prospect and scientific challenges associated with the direct synthesis method from hydrogen and oxygen are also briefly discussed.

Genome-wide evolution of MAPKs family and their expression in response to bacterial infection in seahorse Hippocampus erectus

Seahorses have evolved many unique biological traits,including a male brood pouch,the absence of caudal and pelvic fins,and the lack of spleen and gut-associated lymphatic tissue.The mitogenactivated protein kinases(MAPKs)are known to be involved in various important biological processes including growth,differentiation,immunity,and stress responses.Therefore,we hypothesized that the adaptive evolution and expression of the MAPK gene family in seahorse may differ from those of other teleost species.We identified positive selection sites in the erk2,erk5,jnk1,and p38αMAPK genes of the lined seahorse Hippocampus erectus and tiger-tailed seahorse Hippocampus comes.A novel expression profile of MAPK cascade genes was found in seahorse larvae during the first day after birth based on the RNA-seq data of H.erectus,which refl ected vital signs of immune response to its parental immune system.The expression patterns of the four positively selected MAPK genes were analyzed following the bacterial challenge of Vibrio fortis,revealing their upregulation pattern in brood pouch and other immune tissues.This study enriched our knowledge of the evolution of the H.erectus MAPK subfamilies,and could help better understanding the functional role of MAPKs in teleosts.

An improved least mean square/fourth direct adaptive equalizer for under-water acoustic communications in the Arctic

An improved least mean square/fourth direct adaptive equalizer(LMS/F-DAE)is proposed in this paper for underwater acoustic communication in the Arctic.It is able to process complex-valued baseband signals and has better equalization performance than LMS.Considering the sparsity feature of equalizer tap coefficients,an adaptive norm(AN)is incorporated into the cost function which is utilized as a sparse regularization.The norm constraint changes adaptively according to the amplitude of each coefficient.For small-scale coefficients,the sparse constraint exists to accelerate the convergence speed.For large-scale coefficients,it disappears to ensure smaller equalization error.The performance of the proposed AN-LMS/F-DAE is verified by the experimental data from the 9th Chinese National Arctic Research Expedition.The results show that compared with the standard LMS/F-DAE,AN-LMS/F-DAE can promote the sparse level of the equalizer and achieve better performance.

The price of carbon risk:Evidence from China's bond market

Using a 2009–2019 sample of Chinese bond issuers,we examine the effect of carbon risk on bond financing costs.Relative to low carbon risk issuers,high carbon risk issuers have substantially larger bond credit spreads,mainly because their credit risk is greater and they invest the funds in non-green projects.This positive relationship is more pronounced for issuers with financing constraints,those not making a green transition and those in cities with stringent environmental regulations.We find a reversed effect during the COVID-19 pandemic.However,China’s carbon peak and carbon neutral goals have renewed the focus on carbon risk.Carbon risk also causes bond issuers to scale back production and negatively affects their likelihood of receiving long-term financial support.Our findings suggest that investors consider carbon risk and charge a corresponding risk premium.

Medical image lossless compression based on combining an integer wavelet transform with DPCM

To improve the classical lossless compression of low efficiency,a method of image lossless compression with high efficiency is presented.Its theory and the algorithm implementation are introduced.The basic approach of medical image lossless compression is then briefly described.After analyzing and implementing differential plus code modulation(DPCM)in lossless compression,a new method of combining an integer wavelet transform with DPCM to compress medical images is discussed.The analysis and simulation results show that this new method is simpler and useful.Moreover,it has high compression ratio in medical image lossless compression.