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Photoinduced radical sulfur dioxide insertion with asymmetric cyclization of alkenes: accessing β-chiral sulfones bearing S-stereocentric cyclic sulfinamides

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Science China Chemistry 2025年第1期68卷 257-263页

作者： Jiapian Huang Chenxin Wang Xu Wang Xiaoyu Zhou Wei Xiao Jie Wu School of Pharmaceutical and Chemical Engineering & institute for Advanced Studies Taizhou University State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences School of Chemistry and Chemical Engineering Henan Normal University

The generation of various β-chiral sulfones bearing chiral cyclic sulfinamides through photoredox-catalyzed sulfur dioxide insertion with asymmetric radical cyclization is described. This method features a broad substrate scope and excellent stereospecificity. Computational studies reveal that the dispersion interaction between sulfinyl group and CH2SO2Ph group plays a crucial role in the stereoselectivity control.

关键词： β-chiral sulfones chiral cyclic sulfinamides sulfur dioxide insertion asymmetric radical cyclization stereoselectivity

ASSAY OF BIOLOGICAL ACTIVITY OF SYNTHETIC YEAST ALANINE TRANSFER RNA (tRNAyAla)

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Science China Chemistry 1983年第5期26卷 504-512页

作者：申庆祥余允华张孝勇郭礼和匡达人包俊茹谌章群 shanghai institute of cell biology shanghai institute of biochemistry Academia Sinica

The biological activity of the synthetic tRNAwas studied with an extremely sensitive method, tRNA. accepted alanine in the presence of rat liver aminoacyl-tRNA-synthetase （this was called the accepting actvity）. The aminoacylated tRNAwas conveniently precipitated by ethanol with good recovery. The efficiency of transferring alanine from the aminoacylated tRNAinto the protein was determined in in vitro rabbit reticulocyte lysate cell-free protein-synthesizing system （this was called the incorporation activity）. Both accepting and incorporation activities could be determined in one assay with only 5-7 pmoles of tRNAeither in ligation mixture or in purified *** results show that the accepting activities of the synthetic products were 51.6-65.6% and 91.3-106.0% of that of natural and reconstituted natural tRNArespectively. The efficiency of the incorporation of alanine in the aminoacylated tRNAinto the protein was 61.6-63.1%, corresp

关键词： tRNA_y ASSAY OF BIOLOGICAL ACTIVITY OF SYNTHETIC YEAST ALANINE TRANSFER RNA Ala

Cyano migration-mediated radical-polar crossover cyclopropanation

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Science China Chemistry 2025年第1期68卷 241-248页

作者： Ziqiang Wang Yasu Chen Jie Li Chen Zhu Key Laboratory of Organic Synthesis of Jiangsu Province College of Chemistry Chemical Engineering and Materials ScienceSoochow University Frontiers Science Center for Transformative Molecules Zhangjiang Institute for Advanced Study and Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Shanghai Jiao Tong University

We report a novel cyano migration-mediated radical-polar crossover process, whereby both the sulfonylcyanation of aliphatic alkenes and the formation of cyclopropanes are concurrently achieved. This transformation yields a diverse array of multisubstituted cyclopropanes under mild photocatalytic conditions. Mechanistic studies elucidate that the reaction proceeds via intramolecular nucleophilic substitution, leading to the formation of the cyclopropane derivatives.

关键词： cyclopropanation cyano migration radical-polar crossover radical reactions

Assessing the corrosion protection property of coatings loaded with corrosion inhibitors using the real-time atmospheric corrosion monitoring technique

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 119-126页

作者： Xiaoxue Wang Lulu Jin Jinke Wang Rongqiao Wang Xiuchun Liu Kai Gao Jingli Sun Yong Yuan Lingwei Ma Hongchang Qian Dawei Zhang School of Energy and Power Engineering Beihang UniversityBeijing 100191China Beijing institute of Space Long March Vehicle Beijing 100076China National Materials Corrosion and Protection Data Center University of Science and Technology BeijingBeijing 100083China institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China shanghai Spaceflight Precision Machinery institute Shanghai 201600China

The atmospheric corrosion monitoring(ACM)technique has been widely employed to track the real-time corrosion behavior of metal ***,limited studies have applied ACM to the corrosion protection properties of organic *** study compared a bare epoxy coating with one containing zinc phosphate corrosion inhibitors,both applied on ACM sensors,to observe their corrosion protection properties over *** with artificial damage via scratches were exposed to immersion and alternating dry and wet environments,which allowed for monitoring galvanic corrosion currents in *** the corrosion tests,the ACM currents of the zinc phosphate/epoxy coating were considerably lower than those of the blank epoxy *** trend in ACM current variations closely matched the results obtained from regular electrochemical tests and surface *** alignment highlights the potential of the ACM technique in evaluating the corrosion protection capabilities of organic *** with the blank epoxy coating,the zinc phosphate/epoxy coating showed much-decreased ACM current values that confirmed the effective inhibition of zinc phosphate against steel corrosion beneath the damaged coating.

关键词： atmospheric corrosion monitoring technology corrosion inhibitor coating carbon steel corrosion protection

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GFRF R-CNN:Object Detection Algorithm for Transmission Lines

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Computers, Materials & Continua 2025年第1期82卷 1439-1458页

作者： Xunguang Yan Wenrui Wang Fanglin Lu Hongyong Fan Bo Wu Jianfeng Yu shanghai Advanced Research institute Chinese Academy of SciencesShanghai201210China University of Chinese Academy of Sciences Beijing100049China Jingwei Textile Machinery Co. Ltd.Beijing100176China

To maintain the reliability of power systems,routine inspections using drones equipped with advanced object detection algorithms are essential for preempting power-related *** increasing resolution of drone-captured images has posed a challenge for traditional target detection methods,especially in identifying small objects in high-resolution *** study presents an enhanced object detection algorithm based on the Faster Regionbased Convolutional Neural Network(Faster R-CNN)framework,specifically tailored for detecting small-scale electrical components like insulators,shock hammers,and screws in transmission *** algorithm features an improved backbone network for Faster R-CNN,which significantly boosts the feature extraction network’s ability to detect fine *** Region Proposal Network is optimized using a method of guided feature refinement(GFR),which achieves a balance between accuracy and *** incorporation of Generalized Intersection over Union(GIOU)and Region of Interest(ROI)Align further refines themodel’s *** results demonstrate a notable improvement in mean Average Precision,reaching 89.3%,an 11.1%increase compared to the standard Faster *** highlights the effectiveness of the proposed algorithm in identifying electrical components in high-resolution aerial images.

关键词： Faster R-CNN transmission line object detection GIOU GFR

Constructing quasi-2D perovskite to collect hot carriers to reduce open-circuit voltage loss for efficient inverted perovskite solar cells

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Science China Chemistry 2025年

作者： Lei Gu Xing Li Chao Wu Yang Feng Chunming Yang Lin Song Frontiers Science Center for Flexible Electronics Institute of Flexible Electronics Northwestern Polytechnical University shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences

Inverted perovskite solar cells （PSCs） have received great attention owing to the high certificated power conversion efficiency（PCE） reaching 26.7%. However, interfacial charge recombination is far superior to perovskite bulk charge recombination due to the use of fullerenes and their derivatives in inverted perovskite solar cells, which induces devastating open circuit voltage（VOC） losses. For this reason the present work attempts to use 4-chloropiperidine hydrochloride for the upper surface modification of perovskite to construct a quasi-two-dimensional （2D） structure with suitable 2D layer widths （n=2, 3 dominant）,which has a smaller electron carrier transport barrier without sacrificing short-circuit current （JSC） in the device. This strategy effectively passivates the interfacial defect states while promoting energy level alignment to achieve carrier dissociation and equilibrium transport at the interface, which in turn resulted in improved fill factor （FF）. In addition, additional energy levels are provided by 2D perovskites to collect hot carriers, resulting in improved device open circuit voltage （VOC）. As a result, the device PCE increases from 22.37%to 24.11%after the 4CPD treatment. In addition, the 4CPD-treated PSCs maintain 90%of the initial PCE after storage in an N2atmosphere at 50°C for 1,080 h, whereas the control devices show a 15%PCE loss under the same aging conditions. This work provides new opportunities to suppress interfacial charge recombination in inverted devices.

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Unraveling brain aging through the lens of oral microbiota

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Neural Regeneration Research 2025年第7期20卷 1930-1943页

作者： Qinchao Hu Si Wang Weiqi Zhang Jing Qu Guang-Hui Liu State Key Laboratory of Membrane biology Institute of ZoologyChinese Academy of SciencesBeijingChina Hospital of Stomatology Guanghua School of StomatologyGuangdong Provincial Key Laboratory of StomatologySun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Advanced Innovation Center for Human Brain Protection and National Clinical Research Center for Geriatric Disorders Xuanwu HospitalCapital Medical UniversityBeijingChina Aging Translational Medicine Center International Center for Aging and CancerBeijing Municipal Geriatric Medical Research CenterXuanwu HospitalCapital Medical UniversityBeijingChina CAS Key Laboratory of Genomic and Precision Medicine Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijingChina University of Chinese Academy of Sciences BeijingChina institute for Stem cell and Regeneration Chinese Academy of SciencesBeijingChina Aging Biomarker Consortium BeijingChina State Key Laboratory of Stem cell and Reproductive biology Institute of ZoologyChinese Academy of SciencesBeijingChina Beijing institute for Stem cell and Regenerative Medicine BeijingChina

The oral cavity is a complex physiological community encompassing a wide range of *** of oral microbiota can lead to various oral infectious diseases,such as periodontitis and tooth decay,and even affect systemic health,including brain aging and neurodegenerative *** studies have highlighted how oral microbes might be involved in brain aging and neurodegeneration,indicating potential avenues for intervention *** this review,we summarize clinical evidence demonstrating a link between oral microbes/oral infectious diseases and brain aging/neurodegenerative diseases,and dissect potential mechanisms by which oral microbes contribute to brain aging and *** also highlight advances in therapeutic development grounded in the realm of oral microbes,with the goal of advancing brain health and promoting healthy aging.

关键词： Alzheimer's disease brain aging multiple sclerosis neurodegeneration neurodegenerative diseases oral microbiota Parkinson's disease periodontitis bacteria Porphyromonas gingivalis

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Recent progress in the applications of presynaptic dopaminergic positron emission tomography imaging in parkinsonism

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Neural Regeneration Research 2025年第1期20卷 93-106页

作者： Yujie Yang Xinyi Li Jiaying Lu Jingjie Ge Mingjia Chen Ruixin Yao Mei Tian Jian Wang Fengtao Liu Chuantao Zuo Key Laboratory of Arrhythmias Ministry of EducationDepartment of Medical GeneticsShanghai East HospitalSchool of MedicineTongji UniversityShanghaiChina Department of Neurology National Research Center for Aging and MedicineNational Center for Neurological Disordersand State Key Laboratory of Medical NeurobiologyHuashan HospitalFudan UniversityShanghaiChina Department of Nuclear Medicine&PET Center National Center for Neurological Disordersand National Clinical Research Center for Aging and MedicineHuashan HospitalFudan UniversityShanghaiChina International Human Phenome institutes(shanghai) ShanghaiChina Human Phenome institute Fudan UniversityShanghaiChina

Nowadays,presynaptic dopaminergic positron emission tomography,which assesses deficiencies in dopamine synthesis,storage,and transport,is widely utilized for early diagnosis and differential diagnosis of *** review provides a comprehensive summary of the latest developments in the application of presynaptic dopaminergic positron emission tomography imaging in disorders that manifest *** conducted a thorough literature search using reputable databases such as PubMed and Web of *** criteria involved identifying peer-reviewed articles published within the last 5 years,with emphasis on their relevance to clinical *** findings from these studies highlight that presynaptic dopaminergic positron emission tomography has demonstrated potential not only in diagnosing and differentiating various Parkinsonian conditions but also in assessing disease severity and predicting ***,when employed in conjunction with other imaging modalities and advanced analytical methods,presynaptic dopaminergic positron emission tomography has been validated as a reliable in vivo *** validation extends to screening and exploring potential neuropathological mechanisms associated with dopaminergic *** summary,the insights gained from interpreting these studies are crucial for enhancing the effectiveness of preclinical investigations and clinical trials,ultimately advancing toward the goals of neuroregeneration in parkinsonian disorders.

关键词： aromatic amino acid decarboxylase brain imaging dopamine transporter Parkinson’s disease parkinsonism positron emission tomography presynaptic dopaminergic function vesicle monoamine transporter type 2

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Isolation and characterization of the murine Nanog gene promoter

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cell Research 2005年第5期15卷 317-324页

作者： Da Yong WU, Zhen YAO Laboratory of Molecular cell biology, Laboratory of Stem cell biology, institute of biochemistry and cell biology, shanghai institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, shanghai 200031, China. Laboratory of Molecular cell biology Laboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China

Nanog protein is expressed in the interior cells of compacted morulae and maintained till epiblasts but downregulated by implantation stage. It is also expressed in embryonic stem cells, embryonic carcinoma cells and embryonic germ cells but disappeared in differentiated ES cells. In this study, we have isolated, sequenced, and performed the first characterization of the Nanog promoter. The transcription start sites were mapped by primer extension analysis. Two promoter regions were found upstream the transcription start sites and the expression of major Nanog promoter/ reporter gene construct is abolished in differentiated F9 EC cells as compared to the undifferentiated counterpart. We also showed that a putative octamer motif (ATGCAAAA) is necessary for the major promoter activity. Gel shift and supershift assays showed that Oct-1, Oct-4 and Oct-6 protein selectively bind to the octamer motif.

关键词： Nanog promoter F9 EC cells Oct-1 Oct-4 Oct-6.