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Nickel-Catalyzed Stereoselective Migratory Carboboration of 1,4-Cyclohexadiene

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Chinese Journal of Chemistry 2024年第4期42卷 356-362页

作者： Yaoyu Ren Lujin wang Chao Ding Yangyang Li Guoyin Yin The Institute for Advanced Studies Wuhan UniversityWuhanHubei430072 China

Multi-substituted cyclohexanes play a crucial role as scaffolds in bioactive *** significant progress has been made in synthesizing substituted cyclohexanes,methods for the stereoselective assembly of 1,3-disubstituted cyclohexanes remain *** study presents a novel approach involving nickel catalysis to achieve stereoselective carboboration of 1,*** innovative process allows for the simultaneous introduction of a boron group and an aryl or an alkyl fragment into the 1,4-cyclohexadiene framework under mild conditions,with exclusive regioselectivity and excellent cis *** resulting products feature a double carbon bond and the incorporation of the boron group,offering significant potential for subsequent transformations and downstream applications.

关键词： 1,4-Cyclohexadiene Carboboration Nickel Chain-walking Stereoselectivity Difunctionalization

Cyanidin-3-glucoside protects the photooxidative damage of retinal pigment epithelium cells by regulating sphingolipid signaling and inhibiting MAPK pathway

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Food Science and Human Wellness 2024年第2期13卷 621-632页

作者： Tingting Liu Wentao Qi Wenting Peng Jianan Zhang Yong wang School of Health Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China Academy of National Food and Strategic Reserves Administration Beijing 100037China Department of Chemistry University of North Carolina at Chapel HillChapel HillNC 27599USA

Cyanidin-3-glucoside(C3G)is the most common anthocyanin in dark grains and berries and is a food functional factor to improve visual ***,the mechanisms of C3G on blue light-induced retinal pigment epithelial(RPE)cell photooxidative damage needs further *** investigated the effects of C3G on blue light-irradiated A2E-containing RPE cells and explored whether sphingolipid,mitogen-activated protein kinase(MAPK),and mitochondria-mediated pathways are involved in this *** light irradiation led to mitochondria and lysosome damage in RPE cells,whereas C3G preserved mitochondrial morphology and function and maintained the lysosomal integrity.C3G suppressed the phosphorylation of JNK and p38 MAPK and mitochondria-mediated pathways to inhibit RPE cell *** data showed that C3G protected RPE cells against blue light-induced lipid peroxidation and apoptosis by maintaining sphingolipids balance.C3G significantly inhibited ceramide(Cer d18:0/15:0,Cer d18:0/16:0 and Cer d18:0/18:0)accumulation and elevated galactosylceramide(GalCer d18:1/15:0 and GalCer d18:1/16:0)levels in the irradiated A2E-containing RPE ***,C3G attenuated cell membrane damage by increasing phosphatidylcholine and phosphatidylserine levels.C3G inhibited apoptosis and preserved the structure of mitochondria and lysosome by regulating sphingolipid signaling and suppression of MAPK activation in RPE ***,dietary supplementation of C3G prevents retinal photooxidative damage.

关键词： Cyanidin-3-glucoside Ceramide MAPK pathway Mitochondria-dependent apoptosis Lipidomics analysis

Crack mechanism of ground fissures in loess layer of Fenwei Basin, China

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Journal of Mountain Science 2024年第5期21卷 1683-1696页

作者： LI Cong LU Quanzhong wang Feiyong LUO Wenchao XU Qiang School of Geological Engineering and Geomatics Chang’an UniversityXi’an 710054China Key Laboratory of Western Mineral Resources and Geological Engineering Ministry of EducationXi’an 710054China Observation and Research Station of Ground Fissure and Land Subsidence Ministry of Natural ResourcesXi’an 710054China School of Engineering and Technology China University of GeosciencesBeijing 100083China

The Fenwei Basin, covered by loess, experiences severe ground fissure disasters. These disasters disrupt the continuity of the loess and pose significant threats to engineering construction safety along transportation routes. Nevertheless, the crack characteristics and the influence zone of ground fissures in the loess layer remain inadequately investigated. To effectively prevent and control ground fissure disasters, physical model tests and the PFC(particle flow code) numerical simulation method are used to investigate the crack mechanism of buried ground fissures in the loess layer. The results show that there are two main cracks in the layer profile, which have a Y-shape morphology. As the dip angle of the preset cracks increased from 60° to 90°, the main deformation zone at the surface gradually shifted towards the footwall. The process of crack propagation from depth to surface is divided into five stages. Additionally, the results confirm the accuracy of the width of the rupture zone d2in the footwall calculated by the cantilever beam theory. These findings can offer theoretical guidance for determining the avoidance distance of ground fissures in loess regions, as well as for implementing disaster prevention and corresponding control measures for various stages of buried ground fissure propagation.

关键词： Ground fissure Fenwei Basin Physical model test Particle flow code Crack propagation

Improving the value of molecular testing:current status and opportunities in colorectal cancer precision medicine

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Cancer Biology & Medicine 2024年第1期21卷 21-28页

作者： Haiyun Li Linwei Guo Chenchen wang Xin Hu Ye Xu Department of Colorectal Surgery Fudan University Shanghai Cancer CenterShanghai 200032China Department of Oncology Shanghai Medical CollegeFudan UniversityShanghai 200032China Department of Gastrointestinal Medical Oncology Fudan University Shanghai Cancer CenterShanghai 200032China Precision Cancer Medical Center Affiliated with Fudan University Shanghai Cancer Center Shanghai 201315China

Colorectal cancer(CRC)is the second leading cause of cancer-related deaths *** radical resection with adjuvant chemotherapy remains the primary treatment choice for CRC,but the 5-year postoperative survival rate is only approximately 60%,and approximately one-third of patients with CRC experience recurrence within 2 years of ***,the transformation of high-throughput sequencing has accelerated the development of precision *** example,KRAS mutations indicate resistance to anti-epidermal growth factor receptor(EGFR)-targeted therapies in ***,molecular-guided individualized therapy has brought new promise in major clinical areas and challenges,such as novel biomarkers predicting sensitivity and resistance to immunotherapy for microsatellite stable(MSS)CRC.

关键词： cancer chemotherapy colorectal

Role of Stokes Drift in Ocean Dynamics Under Typhoon Conditions in the Bohai Sea

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Journal of Ocean University of China 2024年第1期23卷 33-45页

作者： LI Haoqian WAN Kai wang Menghan DENG Zeng’an CAO Yu North China Sea Marine Forecasting Center Qingdao 266061China Shandong Provincial Key Laboratory of Marine Ecology and Environment&Disaster Prevention and Mitigation Qingdao 266061China North China Sea Offshore Engineering Survey Institute Qingdao 266061China School of Marine Science and Technology Tianjin UniversityTianjin 300072China South China Sea Marine Forecasting Center Guangzhou 510006China

The effect of Stokes drift production(SDP),which includes Coriolis-Stokes forcing,Langmuir circulation,and Craik-Lei-bovich vortexes,on the upper ocean during typhoon passage in the Bohai Sea(BS),China,is investigated by using a coupled wave-current *** role of SDP in turbulent mixing and the further dynamics during the entire typhoon period are comprehensively *** results show that SDP greatly increases turbulent mixing at all depths under typhoon conditions by up to seven times that under normal weather *** generally strengthens sea surface cooling by more than 0.4℃,with the maximum reduction in sea surface temperature(SST)at the during-typhoon stage exceeding 2℃,which is approximately seven times larger than that under normal weather *** SDP-induced decrease in current speed can exceed 0.2ms^(-1),and the change in current direction is generally opposite the wind *** results suggest that Stokes drift depresses the effect of strong winds on currents by intensifying turbulent *** layer depth(MLD)is distinctly increased by O(1)during typhoons due to SDP and can deepen by more than *** addition,the continuous effects of SDP on SST,current,and MLD at the after-typhoon stage indi-cate a hysteretic response between SDP and typhoon actions.

关键词： Stokes drift production Langmuir turbulence rurbulent mixing typhoon coupled model

Unusual Single Electron Transfer Reactions between Alkenes and Iodine Electrophiles

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Chinese Journal of Chemistry 2024年第5期42卷 471-477页

作者： Zhengzhao Lou Jingyu Hu Chuanfa Ni Xiu wang Jinbo Hu Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Ling Ling RoadShanghai200032 China School of Physical Science and Technology ShanghaiTech University100 Haike RoadShanghai201210 China

The electrophilic addition to an alkene with an electrophile has been widely studied and applied in organic *** organic chemistry textbook describes the classical reaction between an alkene and an iodine electrophile(such as elemental iodine and N-iodosuccinimide(NIS))as a typical ionic reaction,in which an iodonium ion is formed and then attacked by a ***,in this article,we report a new and unusual reaction mode between an alkene and NIS;that is,a single electron transfer(SET)process occurs between these two reactants by forming an electron-donor acceptor *** only does this unusual single electron transfer reaction between an alkene and NIS add fundamentally important knowledge to organic chemistry,it also provides a valuable synthetic method as the new SET reaction mode with opposite regioselectivity as compared with the traditional ionic mode.

关键词： Electrophilic addition Radical ions Reaction mechanisms Alkenes Fluorine

Characteristics and triggering mechanisms of early negative Indian Ocean Dipole

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Acta Oceanologica Sinica 2024年第3期43卷 59-65页

作者： Yue Fang Shuangwen Sun Yongcan Zu Jianhu wang Lin Feng First Institute of Oceanography and Key Laboratory of Marine Science and Numerical ModelingMinistry of Natural ResourcesQingdao 266061China Laboratory for Regional Oceanography and Numerical Modeling Qingdao Marine Science and Technology CenterQingdao 266237China Shandong Key Laboratory of Marine Science and Numerical Modeling Qingdao 266061China

Negative Indian Ocean Dipole(nIOD)can exert great impacts on global climate and can also strongly influence the climate in *** nIOD is a major type of nIOD,which can induce more pronounced climate anomalies in summer than La Niña-related ***,the characteristics and triggering mechanisms of early nIOD are *** results based on reanalysis datasets indicate that the early nIOD and La Niña-related nIOD are the two major types of nIOD,and the former accounts for over one third of all the nIOD events in the past six *** two types of nIODs are similar in their intensities,but are different in their spatial patterns and seasonal *** early nIOD,which develops in spring and peaks in summer,is one season earlier than the La Niña-related *** spatial pattern of the wind anomaly associated with early nIOD exhibits a winter monsoon-like pattern,with strong westerly anomalies in the equatorial Indian Ocean and eastly anomalies in the northern Indian *** to the triggering mechanism of early positve IOD,the early nIOD is induced by delayed Indian summer monsoon *** results of this study are helpful for improving the prediction skill of IOD and its climate impacts.

关键词： Indian Ocean Dipole(IOD) triggering mechanism Indian summer monsoon seasonal cycle negative IOD

Micromechanical modeling of longitudinal tensile behavior and failure mechanism of unidirectional carbon fiber/aluminum composites involving fiber strength dispersion

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Chinese Journal of Aeronautics 2024年第9期37卷 312-327页

作者： Qipeng LIU Wengang JIANG Yuehua GAO Zhenjun wang Shanshan SHI Zhi SUN Jiangxi Key Laboratory of Forming and Joining Technology for Aerospace Components Nanchang Hangkong UniversityNanchang 330063China School of Locomotive and Rolling Stock Engineering Dalian Jiaotong UniversityDalian 116028China State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDalian University of TechnologyDalian 116024China

This paper examines the longitudinal tensile behavior and failure mechanism of a new unidirectional carbon fiber reinforced aluminum composite through experiments and simulations.A Weibull distribution model was established to describe the fiber strength dispersion based on single-fiber tensile tests for carbon fibers extracted from the *** constitutive models for the matrix and interface were established based on the uniaxial tensile and single-fiber push-out tests,***,a 3D micromechanical numerical model,innovatively considering the fiber strength dispersion by use of the weakest link and Weibull distribution theories,was estab-lished to simulate the progressive failure behavior of the composite under longitudinal *** to the dispersion of fiber strength,the weakest link of the fiber first fractures,and stress concentra-tion occurs in the surrounding fibers,interfaces,and *** maximum stress concentration fac-tor for neighboring fibers varies nonlinearly with the distance from the fractured *** isolated and clustered fractured fibers are present during the progressive failure process of the *** expansion of fractured fiber clusters intensifies stress concentration and material degradation which in turn enlarges the fractured fiber clusters,and their mutual action leads to the final collapse of the composite.

关键词： Fiber reinforced metals Finite element method 3D micromechanical model Fiber strength dispersion Longitudinal tension Progressive failure

Cascaded ELM-Based Joint Frame Synchronization and Channel Estimation over Rician Fading Channel with Hardware Imperfections

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China Communications 2024年第6期21卷 87-102页

作者： Qing Chaojin Rao Chuangui Yang Na Tang Shuhai wang Jiafan School of Electrical Engineering and Electronic Information Xihua UniversityChengdu 610039China

Due to the interdependency of frame synchronization(FS)and channel estimation(CE),joint FS and CE(JFSCE)schemes are proposed to enhance their functionalities and therefore boost the overall performance of wireless communication *** traditional JFSCE schemes alleviate the influence between FS and CE,they show deficiencies in dealing with hardware imperfection(HI)and deterministic line-of-sight(LOS)*** tackle this challenge,we proposed a cascaded ELM-based JFSCE to alleviate the influence of HI in the scenario of the Rician fading ***,the conventional JFSCE method is first employed to extract the initial features,and thus forms the non-Neural Network(NN)solutions for FS and CE,***,the ELMbased networks,named FS-NET and CE-NET,are cascaded to capture the NN solutions of FS and *** and analysis results show that,compared with the conventional JFSCE methods,the proposed cascaded ELM-based JFSCE significantly reduces the error probability of FS and the normalized mean square error(NMSE)of CE,even against the impacts of parameter variations.

关键词： channel estimation extreme learning machine frame synchronization hardware imperfection nonlinear distortion synchronization metric