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C_(Ar)-Br bond cleavage via cooperative EnT/NHC catalysis: mild access to indolines

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Science China Chemistry 2024年第3期67卷 922-927页

作者： Yi-Xiong Dong Cao-Bo Li Ming-Lei Jin Zhong-Hua Gao Song Ye Beijing National Laboratory for Molecular sciences CAS Key Laboratory of Molecular Recognition and FunctionCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of sciences Beijing 100049China

The cooperative visible-light mediated and NHC-catalyzed dearomative arylation-acylation of N-(2-bromobenzoyl)indoles with aldehydes was developed, affording the corresponding highly functionalized polycyclic indolines in moderate to good yields with exclusive diastereoselectivities. Mechanism investigations support the activation of CAr-Br bond via visible-light mediated energy transfer(EnT) and the following single-electron-transfer(SET) with Breslow intermediate under NHC catalysis to give key aryl radical and ketyl radical. This protocol demonstrates the cleavage of CAr-Br bond under mild cooperative EnT/NHC catalysis.

关键词： energy transfer N-heterocyclic carbenes photocatalysis aryl radicals indolines

An orally-available monovalent SMAC mimetic compound as a broad-spectrum antiviral

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Protein & Cell 2024年第1期15卷 69-75页

作者： Miao Mei Maria_Antonietta Impagnatiello Jun Jiao Ulrich Reiser Ulrike Tontsch-Grunt Ju Zhang Paul Nicklin Bingke Yu Yu Wang Yuan He Xu Tan Tsinghua-Peking center for Life sciences Beijing Advanced Innovation Center for Structural BiologyBeijing Frontier Research Center for Biological StructureMOE Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical BiologySchool of Pharmaceutical SciencesTsinghua UniversityBeijing 100084China Chinese institutes for Medical research Beijing 100069China Boehringer Ingelheim RCV GmbH&Co KG ViennaAustria College of Life sciences and oceanography Shenzhen UniversityShenzhen 518060China research Beyond Borders Boehringer IngelheimBiberach an der RissGermany research Beyond Borders Boehringer IngelheimShanghai 200120China

DearEditor,The coronavirus disease 2019(COVID-19)pandemic caused great global morbidity and mortality concurrent with astronomical socioeconomic damages and *** now,the culpable pathogen,SARS-CoV-2,has infected over 6 hundred million people resulting in more than 6 million deaths worldwide(WHO SARSCoV-2 cases).There is an urgent need for rapid development of effective and affordable therapeutics for COVID-19 patients.

关键词： mortality spectrum compound

The SLEGS beamline of SSRF

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Nuclear Science and Techniques 2024年第7期35卷 20-30页

作者： Long-Xiang Liu Hong-Wei Wang Gong-Tao Fan Hang-Hua Xu Yue Zhang Zi-Rui Hao Ai-Guo Li Shanghai Advanced research institute Chinese Academy of SciencesShanghai201210China

The Shanghai Laser Electron Gamma Source(SLEGS,located in BL03SSID)beamline at the Shanghai Synchrotron Radiation Facility(SSRF)is a Laser Compton Scattering(LCS)gamma source used for the investigation of nuclear structure,which is in extensive demand in fields such as nulear astrophysics;nulear cdluster structure,polarization physics;and nulear energy The beamline is based on the inverse Compton scattering of 10640 nm photons on 3.5 GeV electrons and a gamma source with va riable energy by changing the scattering angle frorm 20°to 160°.γrays of 0.25-21.1 MeV can be extracted by the scheme consisting of the interaction chamber,coarse collinator,fine collimator,and *** maximum photon flux for 1800 is approximately 10^(7)photons/s at the target at 21.7 MeV,with a 3-mm-diameter *** beamline was equipped with four types of spectrometers for experiments in(Y,Y'),(7,n),(Y,D),and(7,0).At present,Nuclear Resonance Fluorescence(NRF)spectrometry,Flat-Efficiency neutron Detector(FED)spectrometry,neutron Time-OF Flight(TOF)spectrometry,and Light-Charged Particle(LCP)spectrormetry methods have been developed.

关键词： Shanghai Synchrotron Radiation Facility SLEGS Nuclear astrophysics Nuclear structure

Ultrahard X-ray multifunctional application beamline at the SSRF

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Nuclear Science and Techniques 2024年第6期35卷 14-25页

作者： Ke Yang Zhao-Hui Dong Chun-Yin Zhou Zi-Long Zhao Dong-Xu Liang Sai-Chao Cao Ai-Guo Li Shanghai Advanced research institute Chinese Academy of SciencesShanghai 201210China

The ultrahard X-ray multifunctional application beamline(BL12SW)is a phase-II beamline project at the Shanghai Syn-chrotron Radiation *** primary X-ray techniques used at the beamline are high-energy X-ray diffraction and imaging using white and monochromatic *** main scientific objectives of ultrahard X-ray beamlines are focused on two research *** is the study of the structural properties of Earth’s interior and new materials under extreme high-temperature and high-pressure conditions,and the other is the characterization of materials and processes in near-real service *** beamline utilizes a superconducting wiggler as the light source,with two diamond windows and SiC discs to filter out low-energy light(primarily below 30 keV)and a Cu filter assembly to control the thermal load entering the subsequent optical *** beamline is equipped with dual *** first was a meridional bending Laue monochromator cooled by liquid nitrogen,achieving a full-energy coverage of 30-162 *** second was a sagittal bending Laue monochromator installed in an external building,providing a focused beam in the horizontal direction with an energy range of 60-120 *** were four experimental hutches:two large-volume press experimental hutches(LVP1 and LVP2)and two engineering material experimental hutches(ENG1 and ENG2).Each hutch was equipped with various near-real service conditions to satisfy different *** example,LVP1 and LVP2 were equipped with a 200-ton DDIA press and a 2000-ton dual-mode(DDIA and Kawai)press,***1 and ENG2 provide in situ tensile,creep,and fatigue tests as well as high-temperature *** June 2023,the BL12SW has been in trial *** is expected to officially open to users by early 2024.

关键词： Shanghai Synchrotron Radiation Facility Ultrahard X-ray High energy diffraction High energy imaging Engineering materials Earth science

Medcheck:A novel software for automated de-formulation of traditional Chinese medicine(TCM)prescriptions by liquid chromatography-mass spectrometry

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Journal of Pharmaceutical Analysis 2024年第6期14卷 930-932页

作者： Xiao-lan Li Jian-qing Zhang Yun Li Xuan-jing Shen Huan-ya Yang Lin Yang Meng Xu Qi-rui Bi Chang-liang Yao De-an Guo Shanghai research center for Modernization of Traditional Chinese Medicine National Engineering Research Center of TCM Standardization TechnologyShanghai Institute of Materia MedicaChinese Academy of SciencesShanghai201203China b University of Chinese Academy of sciences Beijing100049China

Prescriptions are the main clinical application of traditional Chinese medicines(TCMs).Common forms include Chinese patent medicines,Kampo formulas,and hospital decoctions.A new pre-scription called“famous classical formulas”is recently developed and expected to boom in the *** constituent me-dicinal plants in prescriptions is critical for new drug development and quality control[1],which could avoid safety issues from adulteration or substandard ingredients,as seen in the notorious Longdan Xiegan Pill event.

关键词： medicines formulation prescription

Shell-model representations of the microscopic version of the Bohr–Mottelson collective model

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Communications in Theoretical Physics 2024年第8期76卷 81-92页

作者： H G Ganev Joint institute for Nuclear research Dubna Russia Institute of Mechanics Bulgarian Academy of Sciences

The structure of the irreducible collective spaces of the group Sp（12, R）, which many-particle nuclear states are classified according to the chain Sp（12, R） ? U（6） ? SO（6） ? SUpn（3） ■SO（2） ? SO（3） of the proton–neutron symplectic model（PNSM）, is considered in detail. This chain of the PNSM was recently shown to correspond to a microscopic shell-model version of the Bohr–Mottelson collective model. The construction of the relevant shell-model representations of the Sp（12, R） group along this chain is considered for three nuclei with varying collective properties and from different mass regions. It is shown that the SUpn（3） basis states of the Sp（12, R） representations belonging to the SO（6） irreps with seniority υ ≥ υ0, with υ0denoting the maximal seniority SO（6） irrep contained in the Sp（12, R） bandhead, are always Pauli allowed, but organized in a different way into different SO（6） shells. This is in contrast to the case of filling the levels of the standard three-dimensional harmonic oscillator and using the plethysm operation. Although the SUpn（3） multiplets within υ < υ0are not all Pauli forbidden, it is safe to discard them. The results obtained in the present work are important for the practical application of the microscopic version of the Bohr–Mottelson collective model.

关键词： microscopic shell-model version of the Bohr-Mottelson model proton-neutron symplectic model shell-model representations Sp(12, R) dynamical algebra

Microplastic and Heavy Metals Distributions in Urban Rivers Sediments,China

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Journal of Ocean University of China 2024年第4期23卷 1015-1025页

作者： SONG Dandan SHANG Yujun WANG Xiuli ZHUANG Yuwei GUO Hui BI Shuping HU Jianjun High and New Technology research center of Henan Academy of sciences Zhengzhou 450002China Henan Provincial Cartographic institute Zhengzhou 450008China

This study investigated the distribution of microplastics and heavy metals,along with the interaction between the two in the sediments of urban rivers in *** showed that the abundance of microplastics ranged from 2412±187.5 to 7638±1312items kg^(-1)dry sediment across different survey stations,with an average abundance at(4388±713)items kg^(-1)dry *** further categorization,it was found that transparent fragments were the primary color and type of microplastics *** potential ecological risk index(RI)of heavy metals in sediments suggested a low level of ecological risk within a majority of the urban rivers *** was identified as the main potential ecological risk factor in the sediments of the studied *** was a relatively good significant linear relationship between the RI of heavy metals and the abundance of microplastics,bolstering the linkage between these two environmental ***,the concentrations of heavy metals in microplastics were not dependent on their corresponding contents in *** fact,the concentration of Cu,Cd,and As in microplastics were higher than those in the *** finding confirmed that microplastics could serve as carriers of heavy metals and introduce potential risks to aquatic wildlife and human through the food chain.

关键词： microplastic heavy metals risk assessment river sediments

Interface sites on vanadia-based catalysts are highly active for NO_(x) removal under realistic conditions

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Journal of Environmental sciences 2024年第2期136卷 523-536页

作者： Zhihui Lv Guangzhi He Wenshuo Zhang Jingjing Liu Zhihua Lian Yang Yang Zidi Yan Guangyan Xu Wenpo Shan Yunbo Yu Hong He State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of sciences Beijing 100049China center for Excellence in Regional Atmospheric Environment and Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou 341000China Ningbo research center for Urban Environment Chinese Academy of SciencesNingbo 315800China

TiO_(2)-supported V_(2)O_(5)catalysts are commonly used in NO_(x)reduction with ammonia due to their robust catalytic *** these catalysts,it is generally considered that the active species are mainly derived from the vanadia species rather than the intrinsic structure of V-O-Ti entities,namely the interface *** reveal the role of V-O-Ti entities in NH_(3)-SCR,herein,we prepared TiO_(2)/V_(2)O_(5)catalysts and demonstrated that V-O-Ti entities were more active for NO_(x)reduction under wet conditions than the V sites(V=O)working *** the V-O-Ti entities,kinetic measurements and first principles calculations revealed that NH_(3)activation exhibited a much lower energy barrier than that on V=O *** wet conditions,the V-O-Ti interface significantly inhibited the transformation of V=O to V-OH sites thus benefiting NH_(3)*** wet conditions,meanwhile,the migration of NH_(4)^(+)from Ti site neighboring the V-O-Ti interface to Ti site of the V-O-Ti interface was exothermic;thus,V-O-Ti entities together with neighboring Ti sites could serve as channels linking NH_(3)pool and active centers for activation of NH_(4)^(+).This finding reveals that the V-O-Ti interface sites on V-based catalysts play a crucial role in NO_(x)removal under realistic conditions,providing a new perspective on NH_(3)-SCR mechanism.

关键词： NO_(x)removal Vanadia-based catalysts V-O-Ti entities Interface sites Reaction mechanism

The effect of celastrol in combination with 5-fluorouracil on proliferation and apoptosis of gastric cancer cell lines

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Oncology research 2024年第7期32卷 1231-1237页

作者： MOHAMMAD-TAGHI MORADI DHIYA ALTEMEMY MAJID ASADI-SAMANI PEGAH KHOSRAVIAN MARZIYEH SOLTANI LEILA HASHEMI AZADEH SAMIEI-SEFAT Medical Plants research center Basic Health Sciences InstituteShahrekord University of Medical SciencesShahrekordIran Department of Pharmaceutics College of PharmacyAl-Zahraa University for WomenKarbalaIraq Cellular and Molecular research center Basic Health Sciences InstituteShahrekord University of Medical SciencesShahrekordIran

Background:Despite the availability of chemotherapy drugs such as 5-ﬂuorouracil(5-FU),the treatment of some cancers such as gastric cancer remains challenging due to drug resistance and side *** study aimed to investigate the effect of celastrol in combination with the chemotherapy drug 5-FU on proliferation and induction of apoptosis in human gastric cancer cell lines(AGS and EPG85-257).Materials and Methods:In this in vitro study,AGS and EPG85-257 cells were treated with different concentrations of celastrol,5-FU,and their *** proliferation was assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MTT)*** synergistic effect of 5-FU and celastrol was studied using Compusyn *** DNA content at different phases of the cell cycle and apoptosis rate was measured usingﬂow ***:Co-treatment with low concentrations(10%inhibitory concentration(IC10))of celastrol and 5-FU signiﬁcantly reduced IC50(p<0.05)so that 48 h after treatment,IC50 was calculated at 3.77 and 6.9μM for celastrol,20.7 and 11.6μM for 5-FU,and 5.03 and 4.57μM for their combination for AGS and EPG85-257 cells,*** mean percentage of apoptosis for AGS cells treated with celastrol,5-FU,and their combination was obtained 23.9,41.2,and 61.9,and for EPG85-257 cells 5.65,46.9,and 55.7,*** addition,the 5-FU and celastrol-5-FU combination induced cell cycle arrest in the synthesis ***:Although celastrol could decrease the concentration of 5-ﬂuorouracil that sufﬁced to suppress gastric cancer cells,additional studies are required to arrive at conclusive evidence on the anticancer effects of celastrol.

关键词： Gastric cancer Celastrol Terpenoid Cell cycle regulation Apoptosis Synergism