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Chinese Journal of Chemistry 2022年第9期40卷 1059-1065页

作者： Cong Fu Qi Xiong Lu Xiao Ling He Tian Bai zongpeng zhang Xiu-Qin Dong Chun-Jiang Wang Engineering Research Center of Organosilicon Compounds&Materials Ministry of EducationCollege of Chemistry and Molecular SciencesWuhan UniversityWuhanHubei 430072China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 230021China Suzhou Institute of Wuhan University SuzhouJiangsu 215123China

A novel approach to stereodivergent synthesis of carbocyclicα-quaternary amino acid derivatives,bearing two contiguous stereocenters,is proposed through sequential dual Cu/Ir-catalyzed asymmetric allylation and ring-closing metathesis.A variety of five and six-membered carbocyclicα-quaternary amino acid derivatives could be readily achieved in good to high yields with exclusive regioselectivities,excellent diastereoselectivities(13:1->20:1 dr)and enantioselectivities(generally>99%ee).Of particular note is that the current protocol is also a versatile synthetic tool for the stereodivergent construction of the challenging seven and eight-membered carbocyclicα-amino acid *** four stereoisomers of these important molecules could be precisely synthesized through the permutation of chiral Cu/Ir catalytic *** power of this strategy has been demonstrated for the facile access to some biologically active chiral molecules,such as spiro-hydantoins.

关键词： Asymmetric catalysis Enantioselectivity Amino acids Allylation Metathesis

Copper-catalyzed asymmetric 1,3-dipolar cycloaddition of azomethine ylides withβ-trifluoromethyl-substituted alkenyl heteroarenes

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Science China Chemistry 2023年第11期66卷 3193-3204页

作者： Xiang Cheng Xin Chang Yuhong Yang zongpeng zhang Jing Li Yipu Li Wenxiao Zhao Lung Wa Chung Huailong Teng Xiu-Qin Dong Chun-Jiang Wang College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryShanghai 230021China Shenzhen Grubbs Institute Department of Chemistry and Guangdong Provincial Key Laboratory of CatalysisSouthern University of Science and TechnologyShenzhen 518055China College of Science Huazhong Agricultural UniversityWuhan 430070China

Copper-catalyzed asymmetric 1,3-dipolar cycloaddition of azomethine ylides andβ-trifluoromethyl-substituted alkenyl heteroarenes was developed for the first time.A wide range of enantioenriched pyrrolidines containing both heteroarenes and trifluoromethyl group with multiple stereogenic centers could be readily accessible by this method with good to high yields and excellent levels of both stereo-and regioselectivity(up to 99%yield,>20:1 rr,>20:1 dr,and up to 95%ee).Notably,substratecontrolled umpolung-type dipolar cycloaddition was also disclosed in this protocol to achieve regiodivergent synthesis withα-aryl substituted aldimine esters as the dipole *** DFT studies were conducted to explore the origin of the stereo-and regioselectivity of this 1,3-dipolar cycloaddition,and suggest that copper(Ⅱ)salt utilized in this catalytic system could be reduced in-situ to the active copper(Ⅰ)species and might be responsible for the observed high stereo-and regioselectivity.

关键词： asymmetric catalysis 1 3-dipolar cycloaddition chiral pyrrolidines heteroarene trifluoromethyl group

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A Cullin 5-based complex serves as an essential modulator of ORF9b stability in SARS-CoV-2 replication

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Signal Transduction and Targeted Therapy 2024年第7期9卷 3112-3129页

作者： Yuzheng Zhou zongpeng Chen Sijie Liu Sixu Liu Yujie Liao Ashuai Du Zijun Dong Yongxing zhang Xuan Chen Siyi Tao Xin Wu Aroona Razzaq Gang Xu De-an Tan Shanni Li Youwen Deng Jian Peng Shuyan Dai Xu Deng Xianwen zhang Taijiao Jiang Zheng zhang Gong Cheng Jincun Zhao Zanxian Xia Department of Cell Biology School of Life SciencesCentral South University410013 ChangshaChina Institute for Hepatology National Clinical Research Center for Infectious DiseaseShenzhen Third People’s HospitalThe Second Affiliated HospitalSchool of MedicineSouthern University of Science and Technology518112 ShenzhenChina Department of Basic Medicine School of MedicineHunan Normal University410081 ChangshaChina Department of spine surgery The Third Xiangya HospitalCentral South University410013 ChangshaChina School of Basic Medical Sciences Anhui Medical University230032 HefeiChina Hunan Key Laboratory of Neurorestoratology 921 Hospital of Joint Logistics Support Force People’s Liberation Army of China(The Second Affiliated Hospital of Hunan Normal University)410003 ChangshaHunanChina Department of Geriatric Surgery Xiangya HospitalCentral South University410008 ChangshaChina Xiangya School of Pharmaceutical Sciences Central South University410013 ChangshaChina Institute of Infectious Diseases Shenzhen Bay Laboratory518132 ShenzhenChina Guangzhou Laboratory 510005 GuangzhouChina Tsinghua University-Peking University Joint Center for Life Sciences School of MedicineTsinghua University100084 BeijingChina State Key Laboratory of Respiratory Disease National Clinical Research Center for Respiratory DiseaseGuangzhou Institute of Respiratory HealthThe First Affiliated Hospital of Guangzhou Medical University510120 GuangzhouChina Hunan Key Laboratory of Animal Models for Human Diseases Hunan Key Laboratory of Medical Genetics&Center for Medical GeneticsSchool of Life SciencesCentral South University410008 ChangshaChina

The ORF9b protein,derived from the nucleocapsid’s open-reading frame in both SARS-CoV and SARS-CoV-2,serves as an accessory protein crucial for viral immune evasion by inhibiting the innate immune *** its significance,the precise regulatory mechanisms underlying its function remain *** the present study,we unveil that the ORF9b protein of SARS-CoV-2,including emerging mutant strains like Delta and Omicron,can undergo ubiquitination at the K67 site and subsequent degradation via the proteasome pathway,despite certain mutations present among these ***,our investigation further uncovers the pivotal role of the translocase of the outer mitochondrial membrane 70(TOM70)as a substrate receptor,bridging ORF9b with heat shock protein 90 alpha(HSP90α)and Cullin 5(CUL5)to form a *** this complex,CUL5 triggers the ubiquitination and degradation of ORF9b,acting as a host antiviral factor,while HSP90αfunctions to stabilize ***,treatment with HSP90 inhibitors such as GA or 17-AAG accelerates the degradation of ORF9b,leading to a pronounced inhibition of SARS-CoV-2 ***-cell sequencing data revealed an up-regulation of HSP90αin lung epithelial cells from COVID-19 patients,suggesting a potential mechanism by which SARS-CoV-2 may exploit HSP90αto evade the host *** study identifies the CUL5-TOM70-HSP90αcomplex as a critical regulator of ORF9b protein stability,shedding light on the intricate host–virus immune response dynamics and offering promising avenues for drug development against SARS-CoV-2 in clinical settings.

关键词： stability modulator offering

双金属协同催化立体发散性合成手性非天然α-氨基酸

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科学通报 2023年第30期68卷 3956-3968页

作者：卫亮常鑫张宗朋汪昨非王春江武汉大学化学与分子科学学院武汉430072

手性非天然α-氨基酸是一类重要的化合物,在合成化学和生物医药领域都有十分广泛的应用.通过不对称催化合成高效构建手性非天然α-氨基酸,一直以来都是有机合成化学的研究热点之一,并且已经发展出多种较为成熟的合成途径.其中,最近几年... 详细信息

手性非天然α-氨基酸是一类重要的化合物,在合成化学和生物医药领域都有十分广泛的应用.通过不对称催化合成高效构建手性非天然α-氨基酸,一直以来都是有机合成化学的研究热点之一,并且已经发展出多种较为成熟的合成途径.其中,最近几年兴起的双金属协同催化策略在该领域取得了巨大的成功.双金属协同催化在很多反应中表现出更高的催化活性,特别是可以通过催化剂的合理组合实现目标产物各种光学异构体的立体发散性精准合成,极大提升了该合成方法的高效与实用性,同时也为相关手性非天然α-氨基酸衍生物及其光学异构体的构效关系研究提供了便捷途径.本文对近年来双金属协同催化的立体发散性合成非天然氨基酸的研究进展进行了归纳,主要介绍该策略在亚甲胺叶立德参与的不对称烯丙基化和不对称炔丙基化反应中的应用,并讨论了相关局限性和发展前景.

关键词： α-氨基酸双金属协同催化立体发散性合成不对称烯丙基化不对称炔丙基化

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食品安全监督管理中存在的问题及对策研究

食品安全导刊 2023年第5期 4-6页

作者：张宗鹏滦平县市场监督管理局河北承德068250

食品安全监督是确保食品安全的有力措施,具有非常重要的作用。如今,我国食品安全面临着更大的挑战,对食品安全监管提出了新要求。本文基于食品安全监管现状,介绍了食品安全监管的要求,根据实践分析安全监管问题,提出相关的可行策略,以... 详细信息

食品安全监督是确保食品安全的有力措施,具有非常重要的作用。如今,我国食品安全面临着更大的挑战,对食品安全监管提出了新要求。本文基于食品安全监管现状,介绍了食品安全监管的要求,根据实践分析安全监管问题,提出相关的可行策略,以提升食品安全监管水平。

关键词：食品安全监管问题策略

N-doped graphene quantum dot-decorated N-TiO2/P-doped porous hollow g-C_(3)N_(4) nanotube composite photocatalysts for antibiotic photodegradation and H2 production

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 165-178页

作者： Jingshu Yuan Yao zhang Xiaoyan zhang Junjie zhang Shen’gen zhang Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Xi’an Fanyi University Xi’an 710105China Shunde Graduate School of University of Science and Technology Beijing Foshan 528399China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao SAR 820000China

Exclusive responsiveness to ultraviolet light (~3.2 eV) and high photogenerated charge recombination rate are the two primary drawbacks of pure TiO_(2). We combined N-doped graphene quantum dots (N-GQDs), morphology regulation, and heterojunction construction strategies to synthesize N-GQD/N-doped TiO_(2)/P-doped porous hollow g-C_(3)N_(4) nanotube (PCN) composite photocatalysts (denoted as G-TPCN). The optimal sample (G-TPCN doped with 0.1wt% N-GQD, denoted as 0.1% G-TPCN) exhibits significantly enhanced photoabsorption, which is attributed to the change in bandgap caused by elemental doping (P and N), the improved light-harvesting resulting from the tube structure, and the upconversion effect of N-GQDs. In addition, the internal charge separation and transfer capability of0.1% G-TPCN are dramatically boosted, and its carrier concentration is 3.7, 2.3, and 1.9 times that of N-TiO_(2), PCN, and N-TiO_(2)/PCN(TPCN-1), respectively. This phenomenon is attributed to the formation of Z-scheme heterojunction between N-TiO_(2) and PCNs, the excellent electron conduction ability of N-GQDs, and the short transfer distance caused by the porous nanotube structure. Compared with those of N-TiO_(2), PCNs, and TPCN-1, the H2 production activity of 0.1%G-TPCN under visible light is enhanced by 12.4, 2.3, and 1.4times, respectively, and its ciprofloxacin (CIP) degradation rate is increased by 7.9, 5.7, and 2.9 times, respectively. The optimized performance benefits from excellent photoresponsiveness and improved carrier separation and migration efficiencies. Finally, the photocatalytic mechanism of 0.1% G-TPCN and five possible degradation pathways of CIP are proposed. This study clarifies the mechanism of multiple modification strategies to synergistically improve the photocatalytic performance of 0.1% G-TPCN and provides a potential strategy for rationally designing novel photocatalysts for environmental remediation and solar energy conversion.

关键词： N-doped TiO_(2) N-doped graphene quantum dots P-doped g-C_(3)N_(4) porous hollow nanotube heterojunction photocatalysis

Reversing free-electron transfer of sulfide cocatalyst for exceptional photocatalytic H_(2)evolution

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Journal of Materials Science & Technology 2024年第4期171卷 147-149页

作者： Yanfeng zhang Zhenyi zhang National Experimental Chemistry Teaching Center Hebei Key Laboratory of Inorganic Nano-materialsCollege of Chemistry and Materials ScienceHebei Normal UniversityShijiazhuang 050024China Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian 116600China

Recently,Yu and co-workers deeply explore the potential impact of free electron transfer between co-catalysts and photocatalyst carriers on H_(2)evolution efficiency of active sites over MoS_(2+x).They pro-pose an electron-reversal tactics to evade the unexpected electron transfer and synchronously regulate the above transfer in a beneficial orientation for weakening hydrogen adsorption on S ***,this highlight not only discusses and summarizes the essences of electron reversal and the optimized H ad-sorption/desorption mechanism,but also emphasizes the significance of femtosecond transient absorp-tion spectroscopy(fs-TAS)and in-situ irradiated X-ray photoelectron spectroscopy(ISI-XPS)for revealing charge transfer dynamics and *** anticipate that this highlight can disseminate a new per-spective on the roles of photocatalyst carriers in improving cocatalytic H_(2)-production kinetics.

关键词： Photocatalysis Cocatalyst Electron reversal Antibonding-orbital occupancy S–H bonds

Deep Guided Attention Network for Joint Denoising and Demosaicing in Real Image

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Chinese Journal of Electronics 2024年第1期33卷 303-312页

作者： Tao zhang Ying FU Jun zhang School of Computer Science and Technology Beijing Institute of Technology Advanced Reasearch Institute of Multidisciplinary Science Beijing Institute of Technology

Denoising(DN) and demosaicing(DM) are the first crucial stages in the image signal processing pipeline. Recently, researches pay more attention to solve DN and DM in a joint manner, which is an extremely undetermined inverse problem. Existing deep learning methods learn the desired prior on synthetic dataset, which limits the generalization of learned network to the real world data. Moreover, existing methods mainly focus on the raw data property of high green information sampling rate for DM, but occasionally exploit the high intensity and signalto-noise(SNR) of green channel. In this work, a deep guided attention network(DGAN) is presented for real image joint DN and DM(JDD), which considers both high SNR and high sampling rate of green information for DN and DM, respectively. To ease the training and fully exploit the data property of green channel, we first train DN and DM sub-networks sequentially and then learn them jointly, which can alleviate the error accumulation. Besides, in order to support the real image JDD, we collect paired raw clean RGB and noisy mosaic images to conduct a realistic dataset. The experimental results on real JDD dataset show the presented approach performs better than the state-of-the-art methods, in terms of both quantitative metrics and qualitative visualization.

关键词： Training Visualization Inverse problems Green products Noise reduction Pipelines Signal processing

Value Iteration-Based Cooperative Adaptive Optimal Control for Multi-Player Differential Games With Incomplete Information

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 690-697页

作者： Yun zhang Lulu zhang Yunze Cai the Department of Automation Shanghai Jiao Tong UniversityShanghai 200240 the Key Laboratory of System Control and Information Processing Ministry of Education of ChinaShanghai 200240China

This paper presents a novel cooperative value iteration(VI)-based adaptive dynamic programming method for multi-player differential game models with a convergence *** players are divided into two groups in the learning process and adapt their policies *** method removes the dependence of admissible initial policies,which is one of the main drawbacks of the PI-based ***,this algorithm enables the players to adapt their control policies without full knowledge of others’ system parameters or control *** efficacy of our method is illustrated by three examples.

关键词： Adaptive dynamic programming incomplete information multi-player differential game value iteration

Host plant traits play a crucial role in shaping the composition of epiphytic microbiota in the arid desert,Northwest China

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Journal of Arid Land 2024年第5期16卷 699-724页

作者： zhang Jun zhang Yuanming zhang Qi State Key Laboratory of Desert and Oasis Ecology Key Laboratory of Ecological Safety and Sustainable Development in Arid LandsXinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Xinjiang Key Laboratory of Biodiversity Conservation and Application in Arid Lands Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Xinjiang Field Scientific Observation Research Station of Tianshan Wild Fruit Forest Ecosystem Yili Botanical GardenXinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China College of Life Sciences Shihezi UniversityShihezi 832003China

Phyllosphere microorganisms are a crucial component of environmental microorganisms,highly influenced by host characteristics,and play a significant role in plant health and ***,the impact of host characteristics on shaping phyllosphere microbial communities of plants with different life forms remains *** high-throughput sequencing technology,this study analyzed the diversity and community composition of phyllosphere epiphytic microorganisms(e.g.,bacteria and fungi)of various plant life forms in the hinterland of the Gurbantunggut Desert,Northwest *** annotation of prokaryotic taxa(FAPROTAX)and fungi function guild(FUNGuild)were employed to assess the ecological functions of microorganisms and to investigate the role of stochastic and deterministic processes in shaping phyllosphere microbial *** showed a diverse array of phyllosphere epiphytic microorganisms in the desert plants,with Proteobacteria,Cyanobacteria,and Actinobacteriota dominating bacterial community,while Ascomycota and Basidiomycota were prevalent in fungal *** across different plant life forms highlighted distinct microbial communities,indicating strong filtering effects by plant *** prediction identified intracellular parasites(accounting for 27.44%of bacterial community abundance),chemoheterotrophy(10.12%),and phototrophy(17.41%)as the main functions of epiphytic bacteria on leaves of different life form *** prediction indicated that phyllosphere epiphytic fungi primarily served as Saprotrophs(81.77%),Pathotrophs(17.41%),and Symbiotrophs(0.82%).Co-occurrence network analysis demonstrated a predominance of positive correlations among different microbial ***-Crick dissimilarity index analysis revealed that deterministic processes predominantly influenced phyllosphere bacterial and fungal community *** partitioning analysis and random forest modeling suggested that pla

关键词： phyllosphere epiphytic bacteria phyllosphere epiphytic fungi community structure community diversity functional diversity plant life form plant functional traits