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Asymmetric radical allylation of β-keto esters with vinyl cyclopropanes by dual photoredox/nickel catalysis

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Science China Chemistry 2024年

作者： wen-Yuan Qu Xue-Song Zhou wen-Jing Xiao jia-Rong Chen Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction Ministry of EducationCollege of Chemistry Central China Normal University Wuhan Institute of Photochemistry and Technology Key Laboratory of Organo-Pharmaceutical Chemistry of jiangxi Province Gannan Normal University

Radical-involved allylation reactions have emerged as a powerful platform for construction of carbon-carbon and carbonheteroatom bonds, facilitating the strategic incorporation of diverse allyl moieties. Nevertheless, this burgeoning field still faces ongoing challenges, including limitations of radical precursors and coupling partners, and difficulties in achieving enantiocontrol. Herein, we report for the first time a highly enantioselective radical allylation involving β-keto esters with vinyl cyclopropanes utilizing a synergistic dual photoredox/nickel catalysis under visible light irradiation. The mild and redox-neutral catalytic protocol demonstrates an extensive substrate compatibility and good functional tolerance, providing access to enantioenriched β-keto esters featuring quaternary α-stereocenter with good yields and high enantioselectivities. Preliminary mechanistic studies have uncovered that the success of the reaction hinges on the dual roles of nickel catalyst, including in situ formation of photoredox sensitive substrate/Ni complex and the ensuing asymmetric radical addition step.

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Rapid development of double-hit mRNA antibody cocktail against orthopoxviruses

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1768-1776页

作者： Hang Chi Suo-Qun Zhao Ru-Yi Chen xing-xing Suo Rong-Rong Zhang wen-Hui Yang Dong-Sheng Zhou Min Fang Bo Ying Yong-Qiang Deng Cheng-Feng Qin State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and EpidemiologyAMMS100071BeijingChina College of Life Sciences Inner Mongolia Agricultural UniversityHohhot010018Inner MongoliaChina School of Life Sciences Henan UniversityKaifeng475004HenanChina Suzhou Abogen Biosciences Co. LtdSuzhou215123JiangsuChina Research Unit of Discovery and Tracing of Natural Focus Diseases Chinese Academy of Medical Sciences100071BeijingChina

The Orthopoxvirus genus,especially variola virus(VARV),monkeypox virus(MPXV),remains a significant public health threat *** development of therapeutic antibodies against orthopoxviruses is largely hampered by the high cost of antibody engineering and manufacturing ***-encoded antibodies have emerged as a powerful and universal platform for rapid antibody ***,by using the established lipid nanoparticle(LNP)-encapsulated mRNA platform,we constructed four mRNA combinations that encode monoclonal antibodies with broad neutralization activities against *** vivo characterization demonstrated that a single intravenous injection of each LNP-encapsulated mRNA antibody in mice resulted in the rapid production of neutralizing *** importantly,mRNA antibody treatments showed significant protection from weight loss and mortality in the vaccinia virus(VACV)lethal challenge mouse model,and a unique mRNA antibody cocktail,Mix2a,exhibited superior in vivo protection by targeting both intracellular mature virus(IMV)-form and extracellular enveloped virus(EEV)-form *** summary,our results demonstrate the proof-of-concept production of orthopoxvirus antibodies via the LNP-mRNA platform,highlighting the great potential of tailored mRNA antibody combinations as a universal strategy to combat orthopoxvirus as well as otheremerging viruses.

关键词： proof universal neutral

Clinical application value of long non-coding RNAs signatures of genomic instability in predicting prognosis of hepatocellular carcinoma

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World Journal of Gastrointestinal Surgery 2024年第8期16卷 2386-2392页

作者： Xiao-wen xing Xiao Huang Wei-Peng Li Ming-Ke Wang Ji-Shun Yang Department of Disease Control and Prevention Naval Medical CenterNaval Medical UniversityShanghai 200052China Medical Care Center Naval Medical UniversityShanghai 200052China

Hepatocellular carcinoma(HCC)presents challenges due to its high recurrence and metastasis rates and poor *** current clinical diagnostic and prognostic indicators exist,their accuracy remains imperfect due to their biol-ogical ***,there is a quest to identify improved biomarkers for HCC diagnosis and *** combining long non-coding RNA(lncRNA)expression and somatic mutations,Duan et al identified five representative lncRNAs from 88 lncRNAs related to genomic instability(GI),forming a GI-derived lncRNA signature(LncSig).This signature outperforms previously re-ported LncSig and TP53 mutations in predicting HCC *** this editorial,we comprehensively evaluate the clinical application value of such prognostic evaluation model based on sequencing technology in terms of cost,time,and ***,we provide an overview of various prognostic models for HCC,aiding in a comprehensive understanding of research progress in pro-gnostic evaluation methods.

关键词： Hepatocellular carcinoma Prognosis Prognostic model Biomarkers Genomic instability long non-coding RNA Clinical application value

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石墨膨胀玻化微珠砂浆的吸波性能

建筑材料学报 2013年第3期16卷 396-401页

作者：贾兴文吴洲张亚杰汪宏涛重庆大学材料科学与工程学院重庆400045 后勤工程学院化学与材料工程系重庆400016

采用弓形反射法测试了石墨、膨胀玻化微珠（EVSB）、发泡剂掺量以及材料厚度对石墨膨胀玻化微珠砂浆（GEVSBM）在8～18GHZ吸波性能的影响．结果表明：GEVSBM的吸波性能随石墨掺量的增加逐渐增强，石墨的逾渗阈值为水泥质量的10％；增加E... 详细信息

采用弓形反射法测试了石墨、膨胀玻化微珠（EVSB）、发泡剂掺量以及材料厚度对石墨膨胀玻化微珠砂浆（GEVSBM）在8～18GHZ吸波性能的影响．结果表明：GEVSBM的吸波性能随石墨掺量的增加逐渐增强，石墨的逾渗阈值为水泥质量的10％；增加EVSB或发泡剂掺量可显著增强GEVSBM的吸波性能；石墨和发泡剂掺量分别为水泥质量的10．0％和2．5％时，GEVSBM的反射率降至-20．68dB，小于-10．00dB的有效带宽可达3．0GHZ；试件厚度增大，GEVSBM的反射率逐渐降低，但降低幅度逐渐减小．研究表明，GEVSBM具有良好的吸波和保温性能，可同时满足建筑电磁防护和节能的要求．

关键词：石墨石墨膨胀玻化微珠砂浆反射率吸波性能导热系数

The First Ground-based White Light Lunar Polarization Imaging:A New Kind of FeO Observation on the Near Side of the Moon

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Research in Astronomy and Astrophysics 2024年第6期24卷 1-6页

作者： Wei-Nan Wang Jin-Song Ping Ming-Yuan Wang wen-Zhao Zhang Han-Lin Ye xing-Wei Han Song-Feng Kou Changchun Observatory National Astronomical ObservatoriesChinese Academy of SciencesChangchun 130117China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 101408China Astronomy Department Beijing Normal UniversityBeijing 100875China International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Nanjing Institute of Astronomical Optics and Technology Chinese Academy of SciencesNanjing 210042China

Lunar optical polarization is a fascinating phenomenon that occurs when sunlight reflects off the surface of the Moon and becomes *** study employs a novel split-focus plane polarimetric camera to conduct the initial white light polarimetric observations on the near side of the *** obtained the linear degree of polarization(DOP)parameters of white light by observation from the eastern and western hemispheres of the *** findings indicate that the white light polarization is lower in the lunar highland than in the lunar maria *** the analysis of lunar soil samples,we noticed and determined that the DOP parameters of white light demonstrate high consistency with iron oxide on the *** study may serve as a new diagnostic tool for the Moon.

关键词： techniques:photometric polarization methods:observational Moon

NQO1 Mediates Lenvatinib Resistance by Regulating ROS-induced Apoptosis in Hepatocellular Carcinoma

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Current Medical Science 2024年第1期44卷 168-179页

作者： Wei XUE Ting WANG wen-jing TIAN Si-qi PANG Hua-feng ZHANG Wei-dong jia Department of General Surgery The First Affiliated Hospital of University of Science and Technology of ChinaDivision of Life Science and MedicineUniversity of Science and Technology of ChinaHefei 230027China Institute of Health and Medicine Hefei Comprehensive National Science CenterHefei 230601China The Chinese Academy of Sciences Key Laboratory of Innate Immunity and Chronic Disease School of Basic Medical SciencesDivision of Life Science and MedicineUniversity of Science and Technology of ChinaHefei 230027China

Objective Hepatocellular carcinoma(HCC)is the third leading cause of cancer-associated death *** a first-line drug for advanced HCC treatment,lenvatinib faces a significant hurdle due to the development of both intrinsic and acquired resistance among patients,and the underlying mechanism remains largely *** present study aims to identify the pivotal gene responsible for lenvatinib resistance in HCC,explore the potential molecular mechanism,and propose combinatorial therapeutic targets for HCC *** Cell viability and colony formation assays were conducted to evaluate the sensitivity of cells to lenvatinib and ***-Seq was used to determine the differences in transcriptome between parental cells and lenvatinib-resistant(LR)*** upregulated genes were analyzed by GO and KEGG ***,qPCR and Western blotting were employed to determine the relative gene expression ***,the intracellular reactive oxygen species(ROS)and apoptosis were detected by flow *** PLC-LR and Hep3B-LR were *** was a total of 116 significantly upregulated genes common to both LR cell *** GO and KEGG analyses indicated that these genes were involved in oxidoreductase and dehydrogenase activities,and reactive oxygen species ***,NAD(P)H:quinone oxidoreductase 1(NQO1)was highly expressed in LR cells,and was involved in the lenvatinib *** high expression of NQO1 decreased the production of ROS induced by lenvatinib,and subsequently suppressed the *** combination of lenvatinib and NQO1 inhibitor,dicoumarol,reversed the resistance of LR *** The high NQO1 expression in HCC cells impedes the lenvatinib-induced apoptosis by regulating the ROS levels,thereby promoting lenvatinib resistance in HCC cells.

关键词： hepatocellular carcinoma lenvatinib resistance NAD(P)H quinone oxidoreductase 1 reactive oxygen species apoptosis dicoumarol

Synthesis,Structure and Chemical Bonding of Polyantimony Clusters Containing Coinage Metals[M_(2)Sb_(14)]^(4-)(M=Cu,Ag)

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Chinese Journal of Chemistry 2024年第6期42卷 617-622页

作者： Wei-xing Chen Yu-He Xu Cui-Cui Wang Lei Qiao Zi-Yan Guo wen-Juan Tian Zhong-Ming Sun State Key Laboratory of Element-Organic Chemistry Tianjin Key Lab for Rare Earth Materials and ApplicationsSchool of Materials Science and EngineeringNankai UniversityTianjin300350 China Institute of Molecular Science Shanxi UniversityTaiyuanShanxi030006 China

Binary polyantimony clusters,namely[Cu_(2)Sb_(14)]^(4–) and [Ag_(2)Sb_(14)]^(4–),containing coinage metals,were successfully synthesized and characterized,in which two homoatomic Sb73–subunits are bridged by two coinage metals in η^(4):η^(1) and η^(1):η^(1) coordination modes,***[M_(2)Sb_(14)]^(4-),two bridging Cu ions and two Sb atoms form a planar rhombic unit,which was revealed to have antiaromatic properties by theoretical *** electron structure and bonding analysis confirmed the presence of delocalized bonds in the rhombic unit and the metallophilic interaction between two formal M^(+) ions.

关键词： Polyantimony cluster Copper Silver Antiaromaticity Metallophilic interaction Quantum chemical calculations

Amplification effect of intra-seasonal variability of soil moisture on heat extremes over Eurasia

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Advances in Climate Change Research 2024年第1期15卷 1-8页

作者： Yi-Nuo WANG Zhi-Yan ZUO Liang QIAO Kai-wen ZHANG Mei-Yu CHANG Dong XIAO Zou-xing LIN Huan WANG Department of Atmospheric and Oceanic Sciences Institute of Atmospheric SciencesFudan UniversityShanghai 200438China CMA-FDU Joint Laboratory of Marine Meteorology Shanghai 200438China Key Laboratory of Cites Mitigation and Adaptation to Climate Change in Shanghai China Meteorological AdministrationShanghai 200030China Collaborative Innovation Centeron Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 211800China Shanghai Frontiers Science Center of Atmosphere-Ocean Interaction Shanghai 200123China College of Geography and Resources Science Sichuan Normal UniversityChengdu 610101China National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary Shanghai 202183China Chinese Academy of Meteorological Sciences China Meteorological AdministrationBeijing 100081China

Drying soil has been conducive to a high frequency of extreme high-temperature events over many regions worldwide in recent ***,changes in the intraseasonal variability of soil moisture can also influence the likelihood of extremely high *** previous investigators have examined the association between extremely high temperatures and large-scale atmospheric circulation variability,the role of land-atmosphere coupling dominated by soil moisture variability in extremely high temperatures,particularly over the Eurasian continent,is not well *** this study,on the basis of the Land Surface,Snow,and Soil Moisture Model Intercomparison Project,we found that land-atmosphere feedback amplified the variability of soil moisture in most regions of Eurasia during summer from 1980 to *** amplification of soil moisture variability is closely correlated with more intensive intraseasonal variability of surface air temperature and more frequent occurrences of extreme high-temperature events,particularly in Europe,Siberia,Northeast Asia,and the Indochina *** correlation implies that increasing the intraseasonal variability of soil moisture results in a high likelihood of heat extremes during summer in most parts of Eurasia except Asian desert *** the intraseasonal timescale,the land-atmosphere coupling increases the variability of surface sensible heat flux and net long-wave radiation heating the atmosphere by intensifying the soil moisture variability,thus amplifying the variability of surface air temperature and enhancing the extreme high-temperature *** finding demonstrates the importance of changes in intraseasonal soil moisture variability for the increasing likelihood of heat extremes in summer.

关键词： Soil moisture Intraseasonal variability Land-atmosphere coupling Heat extremes

Landscape ecological risk assessment and its driving factors in the Weihe River basin,China

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Journal of Arid Land 2024年第5期16卷 603-614页

作者： CHANG Sen WEI Yaqi DAI Zhenzhong XU wen WANG xing DUAN jiajia ZOU Liang ZHAO Guorong REN Xiaoying FENG Yongzhong College of Agronomy Northwest A&F UniversityYangling 712100China

Weihe River basin is of great significance to analyze the changes of land use pattern and landscape ecological risk and to improve the ecological basis of regional *** on land use data of the Weihe River basin in 2000,2010,and 2020,with the support of Aeronautical Reconnaissance Coverage Geographic Information System(ArcGIS),GeoDa,and other technologies,this study analyzed the spatial-temporal characteristics and driving factors of land use pattern and landscape ecological *** showed that land use structure of the Weihe River basin has changed significantly,with the decrease of cropland and the increase of forest land and construction *** the past 20 a,cropland has decreased by 7347.70 km2,and cropland was mainly converted into forest land,grassland,and construction *** fragmentation and dispersion of ecological landscape pattern in the Weihe River basin were improved,and land use pattern became more ***,landscape ecological risk of the Weihe River basin has been *** landscape ecological risk area decreased by 19,177.87 km2,high landscape ecological risk area decreased by 3904.35 km2,and moderate and low landscape ecological risk areas continued to *** is worth noting that landscape ecological risks in the upper reaches of the Weihe River basin are still relatively serious,especially in the contiguous areas of high ecological risk,such as Tianshui,Pingliang,Dingxi areas and some areas of Ningxia Hui Autonomous *** ecological risk showed obvious spatial dependence,and high ecological risk area was *** the driving factors,population density,precipitation,normalized difference vegetation index(NDVI),and their interactions are the most important factors affecting the landscape ecological risk of the Weihe River *** findings significantly contribute to our understanding of the ecological dynamics in the Weihe River basin,providing crucial insights for sustainable mana

关键词： land use ecological risk spatiotemporal distribution geographic detector driving factors