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Chiral Betaine-Mediated Asymmetric Peroxidation-Kinetic Resolution Cascade for the Synthesis of Optically Pure Peroxides

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CCS Chemistry 2023年第7期5卷 1509-1516页

作者： Xiangyuan liu Kang Du jisheng Luo li Deng Department of Chemistry Zhejiang UniversityHangzhou 310027 Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province Department of ChemistrySchool of Science and Research Center for Industries of the FutureWestlake UniversityHangzhou 310030

An array of natural products bearing chiral peroxide motifs display antitumor,anticancer,and antiparasitic ***,there are very few catalytic asymmetric syntheses of chiral ***,effective catalysts for asymmetric catalytic peroxidations are limited to chiral *** further expand synthetic access to chiral peroxides,the development of new catalysts realizing catalytic asymmetric peroxidation is highly desirable yet *** report here a catalytic asymmetric peroxidation of anα,β-unsaturated triflone-kinetic resolution cascade reaction,which furnishes chiral peroxides in greater than 99.9%*** realization of this cascade reaction resulted from the development of two betaines as novel catalysts for chiral peroxide synthesis;one betaine promoted enantioselective peroxidation ofα,β-unsaturated triflones via conjugate addition affording peroxides in 80-92%ee,while the other betaine catalyzed kinetic resolution of the newly generated chiral peroxides to further increase the ee to greater than 99.9%.

关键词： chiral peroxide peroxidation kinetic resolution betaine optically pure triflone

Characteristics of nonlinear evolution of wavepackets in boundary layers

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Science China(Physics,Mechanics & Astronomy) 2013年第2期56卷 250-256页

作者： YU Min LUO jisheng li Jia Department of Mechanics Tianjin University

The nonlinear evolution of a finite-amplitude disturbance in a 3-D supersonic boundary layer over a cone was investigated recently by liu et al. using direct numerical simulation （DNS）. It was found that certain small-scale 3-D disturbances amplified rapidly. These disturbances exhibit the characteristics of second modes, and the most amplified components have a well- defined spanwise wavelength, indicating a clear selectivity of the amplification. In the case of a cone, the three-dimensionality of the base flow and the disturbances themselves may be responsible for the rapid amplification. In order to ascertain which of these two effects are essential, in this study we carried out DNS of the nonlinear evolution of a spanwise localized disturbance （wavepacket） in a flat-plate boundary layer. A similar amplification of small-scale disturbances was observed, suggesting that the direct reason for the rapid amplification is the three-dimensionality of the disturbances rather than the three-dimensional nature of the base flow, even though the latter does alter the spanwise distribution of the disturbance. The rapid growth of 3-D waves may be attributed to the secondary instability mechanism. Further simulations were performed for a wavepacket of first modes in a supersonic boundary layer and of Tollmien-Schlichting （T-S） waves in an incompressible boundary layer. The re- suits show that the amplifying components are in the band centered at zero spanwise wavenumber rather than at a finite spanwise wavenumber. It is therefore concluded that the rapid growth of 3-D disturbances in a band centered at a preferred large spanwise wavenumber is the main characteristic of nonlinear evolution of second mode disturbances in supersonic boundary layers.

关键词： boundary layer wavepacket nonlinear evolution second mode spanwise small-scale disturbance

Boosting Zn||I_(2) Battery’s Performance by Coating a Zeolite‑Based Cation‑Exchange Protecting Layer

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Nano-Micro Letters 2022年第5期14卷 168-180页

作者： Wenshuo Shang Qiang li Fuyi Jiang Bingkun Huang jisheng Song Shan Yun Xuan liu Hideo Kimura Jianjun liu litao Kang College of Environment and Materials Engineering Yantai UniversityYantai 264005People’s Republic of China State Key Laboratory of High‑Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China Key Laboratory for Palygorskite Science and Applied Technology of Jiangsu Province Huaiyin Institute of TechnologyHuai’an 223003People’s Republic of China

The intrinsically safe Zn||I_(2) battery,one of the leading candidates aiming to replace traditional Pb-acid batteries,is still seriously suffering from short shelf and cycling lifespan,due to the uncontrolled I_(3)^(−)-shuttling and dynamic parasitic reactions on Zn *** the fact that almost all these detrimental processes terminate on the surfaces of Zn anodes,modifying Zn anodes’surface with protecting layers should be one of the most straightforward and thorough approaches to restrain these ***,a facile zeolite-based cation-exchange protecting layer is designed to comprehensively suppress the unfavored parasitic reactions on the Zn *** negatively-charged cavities in the zeolite lattice provide highly accessible migration channels for Zn^(2+),while blocking anions and electrolyte from passing *** low-cost cation-exchange protecting layer can simultaneously suppress self-discharge,anode corrosion/passivation,and Zn dendrite growth,awarding the Zn||I_(2) batteries with ultra-long cycle life(91.92%capacity retention after 5600 cycles at 2 A g^(−1)),high coulombic efficiencies(99.76%in average)and large capacity(203–196 mAh g^(−1) at 0.2 A g^(−1)).This work provides a highly affordable approach for the construction of high-performance Zn-I_(2) aqueous batteries.

关键词： Zeolite Protecting layer Zn-I_(2)aqueous battery Shuttle Parasitic reactions

Persulfidation-induced Structural Change of SnRK2.6 Establishes Intramolecular Interaction between Phosphorylation and Persulfidation.

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Molecular Plant 2021年第11期14卷 1814-1830页

作者： Sisi Chen Xiaofeng Wang Honglei Jia Fali li Ying Ma Johannes liesche Mingzhi liao Xueting Ding Cuixia liu Ying Chen Na li jisheng li College of life Sciences Northwest A&F UniversityYanglingShaanxi 712100China School of Environmental Science and Engineering Shaanxi University of Science&TechnologyXi'anShaanxi 710021China Viva Biotech(Shanghai)Ltd. Shanghai 201203China National Key Laboratory of Plant Molecular Genetics(NKLPMG) CAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200032China

Post-translational modifications (PTMs) regulate the activity of SNF1-RELATED PROTEIN KINASE2.6 (SnRK2.6), including phosphorylation and persulfidation. here, we report how persulfidations and phosphorylations of SnRK2.6 influence each other. The persulfidation of cysteine C131/C137 altered SnRK2.6 structure, resulted in serine S175 residue more close to aspartic acid D140, who belong to ATP-γ-phosphate proton acceptor may effectively improve the transfer efficiency of phosphate groups to S175, thus persulfidation enhanced the phosphorylation level of S175. S267 and C137 were predicted to lie in close proximity on the protein surface. The phosphorylation status of S267 positively regulated the persulfidation level at C137. Tests of responses of dephosphorylated and depersulfidated mutants to ABA and the H2S-donor NaHS during stomatal closure, water loss, gas-exchange, Ca2+ influx and drought stress revealed that S175/S267-associated phosphorylation and C131/137-associated persulfidation are essential for SnRK2.6 function in vivo. Taken together, we propose a mechanistic model in which certain phosphorylations facilitate persulfidation, which changes SnRK2.6 structure and increases its activity.

关键词： ABA H(2)S Persulfidation Phosphorylation SnRK2.6 drought

Dynamic profiles of DNA methylation and the interaction with histone acetylation during fiber cell initiation of Gossypium hirsutum

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Journal of Cotton Research 2022年第1期5卷 34-47页

作者： CheN Guangyu li Yonghui WEI Zhenzhen GAN Lei liu jisheng WANG Zhi Zhengzhou Research Base State Key Laboratory of Cotton BiologySchool of Agricultural SciencesZhengzhou UniversityZhengzhou 450001China Institute of Cotton Research Chinese Agricultural Academy of SciencesAnyang 455000China

Background:Fiber,as the main product of cotton,provides main raw material for the textile *** key factors have been revealed a significant role in fiber cell development including Myb proteins,phytohormones,fatty acid metabolites,and epigenetic *** methylation is one of the important epigenetic modifications to regulate plant development and responses to abiotic or biotic *** general,DNA methylation consisting of 5mC and 6mA regulates the chromatin structure and gene transcription to affect plant development,however,the detailed role and underlying mechanism of DNA methylation in the fiber development of cotton are yet ***:here,systematical study of the 5mC and 6mA DNA methylation profiles during the fiber initiation period of Xu142 and its glabrous mutant Xu142fl represented a clear alteration of global DNA methylation associated with fiber cell ***,the genome-wide identification of genes responsible for methylation regulation at the fifth carbon of cytosine and the sixth carbon of adenine of DNA was operated in Gossypium *** a result,13,10,6,and 17 genes were identified for 5mC methylation,5mC demethylation,6mA methylation,and 6mA demethylation,*** then investigated the tissue expression pattern of all these genes,and some genes showed higher expression levels in fiber initiation,among which some displayed a significant change in transcription between Xu142 and *** possible interaction between histone acetylation and DNA methylation in fiber initiation through in vitro culture was studied by dot blot,and the results showed that repressed histone deacetylation by Trichostatin A(TSA)inhibited the global DNA methylation,and some causal genes(e.g.,GhDMT13,GhDAMT2,GhALKBH12,GhDM7)were also ***:In this study,all the findings indicated the interplay between histone acetylation and DNA methylation,supporting their important roles and providing precious clues for the epigene

关键词： Fiber initiation DNA methylation Histone acetylation Gossypium hirsutum

Regulation of Leaf Angle by Auricle Development n Maize

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Molecular Plant 2017年第3期10卷 516-519页

作者： Fanying Kong Tingting Zhang jisheng liu Siqi heng Qingbiao Shi Haisen Zhang Zeli Wang Lei Ge Pinghua li Xiaoduo Lu Gang li College of life Science State Key Laboratory of Crop Biology Shandong AgricuLtural University Tai'an Shandong 271018 China College of Agronomy Shandong Agricultural University Tai'an Shandong 271018 China Institute of Molecular Breeding for Maize Qilu Normal University Jinan Shandong 250200 China These authors contributed equally to this article.

In plants, the leaf angle （LA） affects how densely crops can be planted and thus is one of factors determining grain yield per acre. This complex quantitative trait is controlled by developmental signals, hormones, ... 详细信息

关键词： Regulation Leaf Angle Auricle Development in Maize

2014中国国际纺织机械展览会暨ITMA亚洲展览会经编机述评

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针织工业 2014年第7期 21-27页

作者：尹季盛刘丽常德纺织机械有限公司湖南常德415004 天津市针织技术研究所天津300193

介绍2014中国国际纺织机械展览会暨ITMA亚洲展览会经编机和整经机的参展情况及技术特征。指出:应用最广泛并且具有高效产能的特里科经编机是本届展会的热点,国外经编机在新材料、新技术的应用上仍然保持着绝对优势,国内经编机尽管在编... 详细信息

介绍2014中国国际纺织机械展览会暨ITMA亚洲展览会经编机和整经机的参展情况及技术特征。指出:应用最广泛并且具有高效产能的特里科经编机是本届展会的热点,国外经编机在新材料、新技术的应用上仍然保持着绝对优势,国内经编机尽管在编织速度上有了提高,但是在整体水平上仍然存在较大的差距;在弹性和非弹性花边、提花装饰织物领域,近年来市场竞争一直比较激烈,产品正朝着高档次、高附加值方向发展,市场的需求推动了多梳贾卡拉舍尔经编机的发展,国外在机器的整体性能、新机构的应用和所能适应编织的原料等方面还占据着一定的优势;国内产双针床拉舍尔经编机不仅种类多而且整体水平较高,所能编织的织物包括了当前市场上流行的经编间隔(提花)织物、经编绒类、毛毯类织物以及无缝成形织物;国内产单针床弹性、贾卡以及网眼拉舍尔经编机展示了相当高的水平,预示着传统的弹性织物、贾卡提花织物以及网眼织物仍然有相当大的市场需求。

关键词：展览会 ITMA 纺织机械经编机分丝整经机电子技术碳纤维增强材料

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TIP30在肝内胆管癌中的表达及意义

中国普通外科杂志 2021年第2期30卷 187-194页

作者：刘继升刘河刘浩 YU Xing 李浩湖南师范大学附属第一医院/湖南省人民医院肝胆外科湖南长沙410005 浙江省温州市中心医院/上海大学附属第二医院大肠外科浙江温州325000 湖南师范大学医学院湖南长沙410005

背景与目的:抑癌基因HIV-1 Tat相互作用蛋白2(TIP30)在人体多种肿瘤中存在表达下调或缺失,并与患者的不良预后相关。然而,在肝内胆管癌(ICC)中尚未见关于TIP30的研究。本研究旨在探讨TIP30在肝内胆管癌中的表达及临床意义。方法:用免疫... 详细信息

背景与目的:抑癌基因HIV-1 Tat相互作用蛋白2(TIP30)在人体多种肿瘤中存在表达下调或缺失,并与患者的不良预后相关。然而,在肝内胆管癌(ICC)中尚未见关于TIP30的研究。本研究旨在探讨TIP30在肝内胆管癌中的表达及临床意义。方法:用免疫组化法检测51对ICC组织与癌旁组织中TIP30的表达,分析ICC组织中TIP30表达与ICC患者临床病理特征的关系,以及与ICC患者总生存率、累积复发率的关系。用软琼脂克隆法检测TIP30-shRNA转染后ICC细胞(ICC-9810、SSP-25和HuH-28)克隆形成能力的变化。通过数据库TargetScan和miRDB预测可能靶向TIP30的3'UTR的miRNA,用qRT-PCR进一步验证此结果。结果:免疫组化结果显示,TIP30在ICC组织中的表达低于癌旁组织。临床数据分析提示,TIP30表达与淋巴结转移明显有关(P=0.008);生存分析显示,TIP30高表达患者的5年总生存率明显高于TIP30低表达患者(P=0.0412),而累积复发率明显低于TIP30低表达的患者(P=0.0374)。TIP30-shRNA转染后的ICC细胞(ICC-9810、SSP-25和HuH-28)形成的集落数均比阴性对照组明显增加(均P<0.001)。数据库预测结果显示,miR-124-3p可能识别并结合TIP30的3'UTR。qRT-PCR验证结果显示,ICC组织中miR-124-3p的相对含量明显高于癌旁组织(P<0.001);在miR-124-3p转染后的ICC细胞(9810、SSP-25和HuH-28)中TIP30的表达低于阴性对照组(均P<0.05)。结论:TIP30在ICC中的表达水平下调,且与ICC患者预后不良有关,机制可能与ICC中miR-124-3p介导的相关调控有关。本研究结果可能为今后ICC发病机制及分子靶向治疗的研究提供线索和依据。

关键词：胆管肿瘤胆管,肝内 TIP30 预后

基于断裂两侧应变能积累的地震危险性参数估计——以1679年三河—平谷M8.0地震为例

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地震学报 2019年第2期41卷 259-268,I0002页

作者：刘培玄李小军赵纪生北京工业大学建筑工程学院中国北京100124 中国地震局发展研究中心中国北京100036 中国地震局地球物理研究所中国北京100081

本文基于断裂两侧应变能积累的概念,利用新夏垫断裂上探槽研究的古地震资料和1679年三河—平谷M8.0地震的历史资料,通过原地地震复发原则来评价指定断裂(段)在某一时段内的地震危险性,探讨其在未来一段时间内可能发生地震的最大潜在震级... 详细信息

本文基于断裂两侧应变能积累的概念,利用新夏垫断裂上探槽研究的古地震资料和1679年三河—平谷M8.0地震的历史资料,通过原地地震复发原则来评价指定断裂(段)在某一时段内的地震危险性,探讨其在未来一段时间内可能发生地震的最大潜在震级.由此说明现今应变能确定所面临的困难,而应用局部化应变(变形)与岩石-断裂系统局部失稳临界条件之间的联系,理论上可以由变形带的宽度减小率来预估未来地震的发生时间.

关键词：应变能最大潜在震级局部失稳临界条件地震发生时间