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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年第11期67卷 3807-3816页

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.

关键词： asymmetric allylation photoredox catalysis radical addition nickel catalysis β-keto esters vinyl cyclopropanes

Experiment and modelling of texture and sliding direction dependence on finger friction behavior

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Friction 2024年第9期12卷 1955-1968页

作者： Yuanzhe LI xue zhou Pengpeng BAI Zhonghuan XIANG Yonggang MENG Liran MA Yu TIAN State Key Laboratory of Tribology in Advanced Equipment School of Mechanical EngineeringTsinghua UniversityBeijing 100084China

Humans rely on their fingers to sense and interact with external *** the tribological behavior between finger skin and object surface is crucial for various fields,including tactile perception,product appearance design,and electronic skin *** describing finger frictional behavior is always challenging,given the complex structure of the *** this study,the texture and sliding direction dependence of finger skin friction was quantified based on explicit mathematic *** proposed double-layer model of finger skin effectively described the nonlinear elastic response of skin and predicted the scaling-law of effective elastic modulus with contact ***,the skin friction model on textured surface considering adhesion and deformation factors was *** revealed that adhesive term dominated finger friction behavior in daily life,and suggested that object texture size mainly influenced friction-induced vibrations rather than the average friction *** with digital image correlation(DIC)technique,the effect of sliding direction on finger friction was *** was found that the anisotropy in finger friction was governed by the finger’s ratchet pawl structure,which also contributes to enhanced stick-slip vibrations in the distal sliding *** proposed friction models can offer valuable insights into the underlying mechanism of skin friction under various operating conditions,and can provide quantitative guidance for effectively encoding friction into haptics.

关键词： finger friction tactile perception tribological model textured surface sliding direction

Manipulating d-d orbital hybridization induced by Mo-doped Co_(9)S_(8) nanorod arrays for high-efficiency water electrolysis

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Journal of Energy Chemistry 2024年第6期93卷 592-600,I0015页

作者： xue zhou Jing Li Guangyao zhou Weiran Huang Yucan Zhang Jun Yang Huan Pang Mingyi Zhang Dongmei Sun Yawen Tang Lin Xu Jiangsu Key Laboratory of New Power Batteries Jiangsu Collaborative Innovation Centre of Biomedical Functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023JiangsuChina 'College of Science Jinling Institute of TechnologyNanjing 211169JiangsuChina State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Nanjing IPE Institute of Green Manufacturing Industry Nanjing 211100JiangsuChina School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225009JiangsuChina Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Physics and Electronic EngineeringHarbin Normal UniversityHarbin 150025HeilongjiangChina

Precisely refining the electronic structure of electrocatalysts represents a powerful approach to further optimize the electrocatalytic ***,we demonstrate an ingenious d-d orbital hybridization concept to construct Mo-doped Co_(9)S_(8) nanorod arrays aligned on carbon cloth(CC)substrate(abbreviated as Mo-Co_(9)S_(8)@CC hereafter)as a high-efficiency bifunctional electrocatalyst toward water *** has experimentally and theoretically validated that the 4d-3d orbital coupling between Mo dopant and Co site can effectively optimize the H_(2)O activation energy and lower H^(*)adsorption energy barrier,thereby leading to enhanced hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)*** to the unique electronic and geometrical advantages,the optimized Mo-Co_(9)S_(8)@CC with appropriate Mo content exhibits outstanding bifunctional performance in alkaline solution,with the overpotentials of 75 and 234 mV for the delivery of a current density of 10 mA cm^(-2),small Tafel slopes of 53.8 and 39.9 mV dec~(-1)and long-term stabilities for at least 32 and 30 h for HER and OER,*** impressively,a water splitting electrolylzer assembled by the self-supported Mo-Co_(9)S_(8)@CC electrode requires a low cell voltage of 1.53 V at 10 mA cm^(-2)and shows excellent stability and splendid reversibility,demonstrating a huge potential for affordable and scalable electrochemical H_(2) *** innovational orbital hybridization strategy for electronic regulation herein provides an inspirable avenue for developing progressive electrocatalysts toward new energy systems.

关键词： d-d orbital hybridization Transition metal sulfides Nanorods arrays Water electrolysis

Influencing Factors of Communicative Language Teaching:A Student Perspective from English Majors

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Journal of Educational Theory and Management 2024年第2期8卷 50-53页

作者： xue zhou Capital Normal University Beijing100048China

Nowadays,the Communicative Language Teaching Approach has gained significant popularity in the field of foreign language ***,there appears to be a stagnation in its application ***,this thesis aims to investigate the present state of CLT implementation and identify the factors influencing its execution within English major classrooms at Chinese universities from a student perspective.30 students responded to the questionnaire and 5 students participated in interviews to provide detailed *** analysis,it was observed that CLT has been widely used in English classes and received positive feedback from *** including the Test-oriented Educational system,teacher factors,student factors,and the Chinese traditional Confucius idea about teaching have an important impact on its ***,this article offers potential recommendations aimed at reconciling the CLT Approach with the Chinese educational context.

关键词： EFL Foreign language teaching Communicative language teaching Confucianism

从两个“文艺座谈会讲话”透视精神塑造与文化使命

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毛泽东邓小平理论研究 2024年第4期 16-23,108页

作者：薛广洲教育部重点基地湘潭大学毛泽东思想研究中心

毛泽东的《在延安文艺座谈会上的讲话》和习近平的《在文艺工作座谈会上的讲话》虽然时代背景不同,但有着一致的基本立场和主题。当下中国文艺界种种问题的根源都可以通过这两个“文艺座谈会讲话”精神得到正确认识:一是陷于形而上学思... 详细信息

毛泽东的《在延安文艺座谈会上的讲话》和习近平的《在文艺工作座谈会上的讲话》虽然时代背景不同,但有着一致的基本立场和主题。当下中国文艺界种种问题的根源都可以通过这两个“文艺座谈会讲话”精神得到正确认识:一是陷于形而上学思维,二是囿于谬误的“斗争哲学”,三是回避“最终目标”。没有中华文化繁荣兴盛,就没有中华民族伟大复兴,而塑造新时代中国精神,就构成当代文艺工作的使命和目标。对此,重温两个“文艺座谈会讲话”的主要精神,既有助于认识中国精神的时代性和民族性,也有助于走出当下文艺发展困境。

关键词：毛泽东习近平文艺座谈会讲话当代中国精神

Efficacy of Chinese Medicine Treatment Based on Syndrome Differentiation for Primary Insomnia:A Randomized Placebo Controlled Triple-Blinded Trial

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Chinese Journal of Integrative Medicine 2024年第10期30卷 867-876页

作者： XIONG Zhi-yi LU Ying HE Li-yun ZHANG Run-shun zhou xue-zhong LI Peng LIU Yan-jiao ZHU Jian-gui YAN Shi-yan LIU Bao-yan International Acupuncture and Moxibustion Innovation Institute School of Acupuncture-Moxibustion and TuinaBeijing University of Chinese MedicineBeijing100029China Department of Biomedical Data Science Stanford University School of MedicineStanfordCA94305USA Institute of Basic Research in Clinical Medicine China Academy of Chinese Medical SciencesBeijing100700China Guang’anmen Hospital China Academy of Chinese Medical SciencesBeijing100053China School of Computer and Information Technology Beijing Jiaotong UniversityBeijing100044China Beijing Xicheng District Community Healthcare Center Beijing100120China China Academy of Chinese Medical Sciences Beijing100700China

Objective:To assess efficacy of Chinese medicine(CM)on insomnia considering characteristics of treatment based on syndrome ***:A total of 116 participants aged 18 to 65 years with moderate and severe primary insomnia were randomized to the placebo(n=20)or the CM group(n=96)for a 4-week treatment and a 4-week *** CM clinicians independently prescribed treatments for each patient based on syndromes *** primary outcome was change in total sleep time(TST)from *** endpoints included sleep onset latency(SOL),wake time after sleep onset(WASO),sleep efficiency,Pittsburgh Sleep Quality Index(PSQI)and CM ***:The CM group had an average 0.6 h more(95%confidence interval(CI):0.3–0.9,P<0.001)TST and 34.1%(10.3%–58.0%,P=0.005)more patients beyond 0.5 h TST increment than that of the placebo *** was changed–3.3(–3.8 to–2.7)in the CM group,a–2.0(–3.2 to–0.8,P<0.001)difference from the placebo *** CM symptom score in the CM group decreased–2.0(–3.3 to–0.7,P=0.003)more than the placebo *** and WASO changes were not significantly different between *** analysis of prescriptions by these clinicians revealed blood deficiency and Liver stagnation as the most common *** for these clinicians displayed relative stability,while the herbs *** adverse events were mild and were not related to study ***:CM treatment based on syndrome differentiation can increase TST and improve sleep quality of primary *** is effective and safe for primary *** future studies,the long-term efficacy validation and the exploratory of eutherapeutic clinicians'fixed herb formulas should be addressed.(Registration ***01613183).

关键词： primary insomnia Chinese medicine syndrome differentiation randomized controlled trial

RGS22 maintains the physiological function of ependymal cells to prevent hydrocephalus

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Science China Life Sciences 2024年

作者： xue Pang Lin Gu Qiu-Ying Han Jia-Qing Xing Ming Zhao Shao-Yi Huang Jun-Xi Yi Jie Pan Hao Hong Wen xue xue-Qing zhou Zhi-Hui Su Xin-Ran Zhang Li-Ming Sun Shao-Zhen Jiang Dan Luo Ling Chen Zheng-Jie Wang Yu Yu Tian Xia xue-Min Zhang Ai-Ling Li Tao zhou Hong Cai Tao Li Nanhu Laboratory National Center of Biomedical Analysis School of Basic Medical Sciences Fudan University Department of Basic Medical Sciences School of Medicine Tsinghua University

Ependymal cells line the wall of cerebral ventricles and ensure the unidirectional cerebrospinal fluid （CSF） flow by beating their motile cilia coordinately. The ependymal denudation or ciliary dysfunction causes hydrocephalus. Here, we report that the deficiency of regulator of Gprotein signaling 22 （RGS22） results in severe congenital hydrocephalus in both mice and rats. Interestingly, RGS22 is specifically expressed in ependymal cells within the brain. Using conditional knock-out mice, we further demonstrate that the deletion of Rgs22 exclusively in nervous system is sufficient to induce hydrocephalus. Mechanistically, we show that Rgs22 deficiency leads to the ependymal denudation and impaired ciliogenesis. This phenomenon can be attributed to the excessive activation of lysophosphatidic acid receptor （LPAR） signaling under Rgs22–/–condition, as the LPAR blockade effectively alleviates hydrocephalus in Rgs22–/–rats. Therefore, our findings unveil a previously unrecognized role of RGS22 in the central nervous system, and present RGS22 as a potential diagnostic and therapeutic target for hydrocephalus.

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Multitarget Thiol-Activated Tetrapyridyl Gold(Ⅲ)Complexes for Hypoxic Cancer Therapy

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CCS Chemistry 2024年第3期6卷 783-797页

作者： xue-Quan zhou Selda Abyar Imma Carbo-Bague Lan Wang Sebastian Türck Maxime ASiegler Uttara Basu Ingo Ott Rongfang Liu Adriaan PIJzerman Sylvestre Bonnet Institute of Biopharmaceutical and Health Engineering Tsinghua Shenzhen International Graduate School(SIGS)Tsinghua UniversityShenzhen 518055 Leiden Institute of Chemistry Leiden University2333 CC Leiden Department of Chemistry Simon Fraser UniversityBurnabyBritish Columbia V5A 1S6 Institute of Medicinal and Pharmaceutical Chemistry Technische Universität Braunschweig38106 Braunschweig Department of Chemistry Johns Hopkins UniversityBaltimoreMaryland 21218 Division of Drug Discovery&Safety Leiden Academic Centre for Drug ResearchLeiden University2333 CC Leiden

Gold complexes have emerged as promising anticancer metallodrugs due to their efficient thioredoxin reductase(TrxR)inhibition,which disturbs the redox balance of cancer ***,in this model,the role of the ligand(s)coordinated to gold is often *** this work,we present a series of tetrapyridyl Au(Ⅲ)complexes that exhibit thiol-induced release of a Au(Ⅰ)ion and a tetrapyridyl *** formation of a free Au(Ⅰ)center is responsible for the expected TrxR ***,the released ligand,which was visible in cells due to its intense blue fluorescence,showed excellent binding properties to the hERG potassium ***,these ligands ended up in the lysosomes,resulting in significant lysosome ***,the Au(Ⅲ)complexes presented in this work showed broad-spectrum anticancer properties,both in hypoxic 2D monolayers and 3D tumor *** suggest that the interaction of the released Au(Ⅰ)center and the tetrapyridyl ligand with two different protein targets may combine into prodrugs that overcome hypoxia-induced drug deactivation.

关键词： anticancer Au(Ⅲ)complexes enzyme inhibtion potassium channel affinity lysosome damage cell imaging prodrug

ZIF衍生的中空NiS_(2)/CoS_(2)@HNC的制备及储锂性能

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科学通报 2024年第3期69卷 464-472页

作者：周雪陈平刘莹孙晓杰大连理工大学化工学院精细化工国家重点实验室大连116024

过渡金属硫化物是石墨负极材料的优异替代品,但其导电性差、充放电过程中体积膨胀严重.针对这些问题,本文从组成和结构设计的角度出发,通过自模板法简单高效地合成中空十二面体结构的NiS_(2)/CoS_(2)@HNC复合材料.研究表明,NiS_(2)/CoS_... 详细信息

过渡金属硫化物是石墨负极材料的优异替代品,但其导电性差、充放电过程中体积膨胀严重.针对这些问题,本文从组成和结构设计的角度出发,通过自模板法简单高效地合成中空十二面体结构的NiS_(2)/CoS_(2)@HNC复合材料.研究表明,NiS_(2)/CoS_(2)@HNC复合材料用于锂电池负极时显示出良好的电化学性能,在0.2 A g^(−1)电流密度下循环100圈能达到828 mA h g^(−1)的高可逆容量,还具有优异的倍率性能.这主要得益于材料中不同成分间的协同作用以及结构优势,中空氮碳层封装NiS_(2)、CoS_(2)纳米颗粒,缩短了Li+的传输路径,增强了材料的导电性,同时很好地缓解了Li+脱嵌过程中体积膨胀造成的容量衰减.

关键词：锂离子电池负极材料过渡金属硫化物中空结构