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Chinese Chemical Letters 2024年第5期35卷 135-140页

作者： Zhen Liu zhi-Yuan Ren chen Yang Xiangyi Shao Li chen xin Li State Key Laboratory of Elemento-Organic Chemistry Frontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin 300071China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Zhenhai High School of Zhejiang Ningbo 315299China

Catalytic enantioselective alkenylation is an efficient method to construct chiral alkene molecules,but the asymmetric alkenylation of simple alkenes catalyzed by metal-free catalysts remains an elusive ***,we reported an asymmetric alkenylation of benzoxazinones with diarylethylenes by utilizing a B(C_(6)F_(5))_(3)/chiral phosphoric acid catalyst.A broad of benzoxazinones and diarylethylenes with electron-withdrawing and electron-donating groups were tolerated(up to 95%yield and 97.5:2.5 e.r.)in the methodology under mild reaction ***,the synthetic utility was confirmed by the scaled-up reaction and transformations of the *** mechanism was preliminarily explored by control reactions,nonlinear effect experiment and DFT calculations.

关键词： Asymmetric alkenylation Simple alkenes Benzoxazinones B(C_(6)F_(5))_(3)/chiral phosphoric acid Theoretical calculations

Global, regional, and national burden of gallbladder and biliary diseases from 1990 to 2019

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World Journal of Gastrointestinal Surgery 2023年第11期15卷 2564-2578页

作者： Zhong-Zhuan Li Lin-Jing Guan Rong Ouyang zhi-xin chen Guo-Qing Ouyang Hai-xing Jiang Department of Gastroenterology The First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina Department of Gastroenterology Liuzhou Workers’Hospital(The Fourth Affiliated Hospital of Guangxi Medical University)Liuzhou 545007Guangxi Zhuang Autonomous RegionChina Department of Abdomen Ultrasound Nanning Sixth People’s HospitalNanning 530002Guangxi Zhuang Autonomous RegionChina Department of General Surgery Liuzhou People’s Hospital Affiliated to Guangxi Medical UniversityLiuzhou 545006Guangxi Zhuang Autonomous RegionChina

BACKGROUND Gallbladder and biliary diseases(GABDs)are a major public health *** To analysis the cause-specific incidence,prevalence,and years lived with disability(YLDs)and its temporal trends of GABDs at the global,regional,and national *** on GABD were available from the Global Burden of Disease study *** The estimated annual percentage change(EAPC)was used to quantify temporal trend in GABD age-standardized incidence rates(ASIRs),age-standardized prevalence rate(ASPR),and age-standardized YLD rate(ASYR)by region,*** analyzed the relationship between the GABD burden and country development level using the human development index(HDI).RESULTS In 2019,the incident cases of GABD were 52003772,with an ASIR of 63432/100000 ***,the number of incident cases and ASIR of GABD increased 97%and 58.9%between 1990 and ***,the ASPR and ASYR decreased from 1990 to 2019,the number of prevalent and YLDs cases *** highest ASIR was observed in Italy,and the highest ASPR and ASYR was observed in United *** highest burden of GABD was found in low-SDI region,and the burden in female was significantly higher than males.A generally negative correlation(ρ=-0.24,P<0.05)of GABD with the EAPC and human development index(HDI)(in 2021)were observed for ***’s more,no correlation in ASPR(ρ=-0.06,P=0.39)and ASYR(ρ=-0.07,P=0.36)of GABD with the EAPC and HDI(in 2021)were observed,*** GABD remain a major global public health challenge;however,the burden of GABD varies ***,the number of incident cases and ASIR of GABD increased between 1990 and *** results of our study provide insight into the global disease burden of GABD and may assist policymakers in formulating effective policies to mitigate modifiable risk factors.

关键词： Gallbladder and biliary diseases,incidence,prevalence,years lived with disability The Global Burden of Diseases study Estimated annual percentage changes

Cutting performance of saw blades with microtextured rougher and finisher sawteeth

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Advances in Manufacturing 2024年第2期12卷 317-334页

作者： Yang Lu Jian-xin Deng zhi-Hui Zhang Jia-xing Wu Ran Wang Yi-chen Bao Key Laboratory of High Efficiency and Clean Mechanical Manufacture of MOE School of Mechanical EngineeringShandong UniversityJinan250061People’s Republic of China

The problems of severe sawtooth wear,harsh sawing noise,and low surface quality during the processing of circular saw blades need to be *** improve the cutting performance of TiC-based cermet saw blades,microtextures parallel to the cutting edge were fabricated on rough and fine sawteeth by laser *** cutting tests were performed on a sawing platform under lubricated *** of the sawing arc length and working sawtooth cutting force variations were developed for sawing steel pipes,and the accuracy of the sawing force model was verified *** results indicate that the variations in the sawing force are proportional to the sawing arc *** circular saw blades with microtextures that did not penetrate the sawtooth rake face exhibited the lowest cutting force,sawing noise,and highest machined surface ***,the worn-out distance of the rougher and finisher sawteeth was reduced by approximately 7.4%and 44.1%,respectively,compared with conventional circular saw *** main failure modes of sawteeth were tip wear,rake face adhesion,and oxidative *** addition,the mechanism by which the textures improve the cutting and wear properties of TiC-based circular saw blades was *** study provided a significant concept for enhancing the cutting performance of circular saw blades and improving the machined surface quality.

关键词： Circular saw blades Micro textures Cutting performance Wear performance

Dominant woody plant species recognition with a hierarchical model based on multimodal geospatial data for subtropical forests

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Journal of Forestry Research 2024年第3期35卷 111-130页

作者： xin chen Yujun Sun State Forestry&Grassland Administration Key Laboratory of Forest Resources&Environmental Management Beijing Forestry UniversityBeijing 100083People's Republic of China

Since the launch of the Google Earth Engine(GEE)cloud platform in 2010,it has been widely used,leading to a wealth of valuable ***,the potential of GEE for forest resource management has not been fully *** extract dominant woody plant species,GEE combined Sen-tinel-1(S1)and Sentinel-2(S2)data with the addition of the National Forest Resources Inventory(NFRI)and topographic data,resulting in a 10 m resolution multimodal geospatial dataset for subtropical forests in southeast *** and texture features,red-edge bands,and vegetation indices of S1 and S2 data were computed.A hierarchical model obtained information on forest distribution and area and the dominant woody plant *** results suggest that combining data sources from the S1 winter and S2 yearly ranges enhances accuracy in forest distribution and area extraction compared to using either data source ***,for dominant woody species recognition,using S1 winter and S2 data across all four seasons was *** terrain factors and removing spatial correlation from NFRI sample points further improved the recognition *** optimal forest extraction achieved an overall accuracy(OA)of 97.4%and a maplevel image classification efficacy(MICE)of 96.7%.OA and MICE were 83.6%and 80.7%for dominant species extraction,*** high accuracy and efficacy values indicate that the hierarchical recognition model based on multimodal remote sensing data performed extremely well for extracting information about dominant woody plant *** the results using the GEE application allows for an intuitive display of forest and species distribution,offering significant convenience for forest resource monitoring.

关键词： Google Earth Engine Sentinel Forest resource inventory data Dominant woody plant species Subtropics Model performance

A facile strategy for large-scale production of 2D nanosheets exfoliated by three-roll milling

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Journal of Advanced Ceramics 2024年第1期13卷 11-18页

作者： xin Wang Yang Xia Juntong Huang Yao Su zhi chen Linlin chen Zhaohui Wu zhijun Feng Huiyong Yang Xibao Li School of Materials Science and Engineering Nanchang Hangkong UniversityNanchang 330063China

Two-dimensional(2D)nanomaterials,such as graphene,MoS_(2),and MAX,have attracted increasing research attention in recent years due to their unique structural and performance ***,their complex production processes and equipment requirements are significant issues affecting their widespread ***,with an exfoliation strategy using three-roll milling,we present a simple,cost-effective,and extensible method to produce multilayer graphene,BN,MoS_(2),and Ti_(3)AlC_(2) *** roller and phenolic resin created three kinds of forces on the layered 2D materials,i.e.,shear forces,compressive forces,and adhesive forces,which exfoliated layered materials from their edges and surfaces into ***,the exfoliated materials were ultrasonically washed with alcohol,treated with ultrasonic vibration,and centrifuged to obtain 2D *** easy operation and high yield are attractive for research based on the construction of high-performance 2D nanosheet-based devices at low ***,the obtained multilayer graphene and MoS_(2) nanosheets were used as anode materials of sodium/potassium-ion batteries,respectively,to test their electrochemical *** performances are obtained compared with their primary bulk materials.

关键词： two-dimensional(2D)nanosheets exfoliation three-roll milling(TRM) sodium/potassium-ion batteries

Mesenchymal stem cells for repairing glaucomatous optic nerve

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 748-760页

作者： Bai-Yu Hu Mei xin Ming chen Ping Yu Liu-zhi Zeng Eye School of chengdu University of TCM Chengdu 610000Sichuan ProvinceChina Department of Ophthalmology Chengdu First People’s HospitalChengdu 610095Sichuan ProvinceChina

Glaucoma is a common and complex neurodegenerative disease characterized by progressive loss of retinal ganglion cells(RGCs)and ***,there is no effective method to address the cause of RGCs ***,studies on neuroprotective strategies for optic neuropathy have increased in recent *** replacement and neuroprotection are major strategies for treating glaucoma and optic *** medicine research into the repair of optic nerve damage using stem cells has Received considerable *** cells possess the potential for multidirectional differentiation abilities and are capable of producing RGCfriendly microenvironments through paracrine *** article reviews a thorough researches of recent advances and approaches in stem cell repair of optic nerve injury,raising the controversies and unresolved issues surrounding the future of stem cells.

关键词： stem cell glaucoma retinal ganglion cell optic nerve axon regeneration

Hierarchical V_(3)S_(4)/C nanofibers with fast kinetics for superior alkali metal batteries

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Rare Metals 2024年第4期43卷 1836-1844页

作者： Li chen zhi-xin Rao zhi chen Zhao-Hui Wu Shuai Yang zhi-Jun Feng Hui-Yong Yang Fan-Yan Zeng Xi-Bao Li Jin-Yang Hu Jun-Tong Huang School of Materials Science and Engineering Nanchang Hangkong UniversityNanchang330063China School of Aeronautical Manufacturing Engineering Nanchang Hangkong UniversityNanchang330063China

Owing to the numerous benefits,including low cost and great theoretical capacity,V3S4 has been a research hotspot for Li^(+)/Na^(+)/K^(+) ***,the V_(3)S_(4) electrode with long cycling stability and high specific capacities continues to pose significant *** this work,vacuum vulcanization is combined with electrospinning to synthesize V_(3)S_(4)/C composite nanofibers(V_(3)S_(4)@CNF).

关键词： composite fibers kinetics

Prediction for permeability index of blast furnace based on VMD-PSO-BP model

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Journal of Iron and Steel Research(International) 2024年第3期31卷 573-583页

作者： Xiao-jie Liu Yu-jie Zhang xin Li zhi-feng Zhang Hong-yang Li Ran Liu Shu-jun chen School of Metallurgy and Energy North China University of Science and TechnologyTangshan 063210HebeiChina chengde Branch HBIS Group Co.Ltd.Chengde 067000HebeiChina

The permeability index is one of the important production indicators to monitor the operation of blast *** is crucial to grasp the trends of changes in the new permeability index in *** the complex vibration spectrum of the permeability index,a prediction model of the permeability index based on the VMD-PSO-BP(variational mode decomposition-particle swarm optimization-back propagation)method was ***,the key factors that affect the permeability index of blast furnace were studied from multiple ***,the permeability index was divided into multiple sub-modes based on the difference of frequency bands by the VMD algorithm,and a PSO-BP prediction model was established for each ***,the prediction results of each sub-mode were summed to obtain the final *** results show that the composite prediction accuracy by using the VMD algorithm is 3%higher than that of the traditional prediction method,which has better applicability.

关键词： Big data-Blast furnace Air permeability Variational mode decomposition Particle swarm optimization Back propagation Model prediction

Heterogeneous body compositions and all-cause mortality in acute coronary syndrome patients:a ten-year retrospective cohort study

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Journal of Geriatric Cardiology 2024年第5期21卷 534-541页

作者： Guang-zhi LIAO Lin BAI Yu-Yang YE Xue-Feng chen xin-Ru HU Yong PENG Department of Cardiology West China HospitalSichuan UniversityChengduSichuanChina

BACKGROUND The association of different body components,including lean mass and body fat,with the risk of death in acute coronary syndrome(ACS)patients are *** We enrolled adults diagnosed with ACS at our center between January 2011 and December 2012 and obtained fol-low-up outcomes via telephone *** used restricted cubic splines(RCS)with the Cox proportional hazards model to analyze the associations between body mass index(BMI),predicted lean mass index(LMI),predicted body fat percentage(BF),and the value of LMI/BF with 10-year *** also examined the secondary outcome of death during *** During the maximum 10-year follow-up of 1398 patients,331 deaths(23.6%)occurred,and a U-shaped relationship was found between BMI and death risk(P_(nonlinearity)=0.03).After adjusting for age and history of diabetes,the overweight group(24≤BMI<28 kg/m^(2))had the lowest mortality(HR=0.53,95%CI:0.29-0.99).Predicted LMI and LMI/BF had an inverse linear relationship with a 10-year death risk(P_(nonlinearity)=0.24 and P_(nonlinearity)=0.38,respectively),while an increase in BF was associ-ated with increased mortality(P_(nonlinearity)=0.64).During hospitalization,31 deaths(2.2%)were recorded,and the associations of the indicators with in-hospital mortality were consistent with the long-term outcome *** Our study provides new insight into the“obesity paradox”in ACS patients,highlighting the importance of considering body composition *** LMI and BF may serve as useful tools for assessing nutritional status and predicting the prognosis of ACS,based on their linear associations with all-cause mortality.

关键词： patients mortality coronary

Evaluation of 3D crustal seismic velocity models in southwest China:Model performance,limitation,and prospects

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Science China Earth Sciences 2024年第2期67卷 604-619页

作者： xin WANG Ling chen Qi-Fu chen Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing100049China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China

Southwest China is a tectonically and seismically active region,witnessing strong deformation due to the collision between the Indian and Eurasian *** the subsurface velocity structure of this region is thus important in understanding the tectonics and geodynamic processes of continental collision and in mitigating seismic *** studies have provided various 3D seismic velocity models in southwest ***,discrepancies exist among these models,and less effort has been made to quantify the reliability and accuracy of these existing velocity *** this study,we use regional 3D waveform simulation to evaluate the performance of various regional crustal 3D velocity models in reproducing observed *** particularly focus on two recent earthquake sequence in the region,the 2021 Yunnan Yangbi MS_(6.4) earthquake sequence and the 2022 Sichuan Luding MS_(6.8) earthquake *** tested 3D velocity models include the Southwest China Community Velocity model V1.0,the Unified Seismic Tomography Models for Continental China Lithosphere V2.0,the adjoint full waveform tomography model of the crustal and upper mantle beneath Eastern Tibetan Plateau,and the shallow seismic structure model beneath continental *** results show that the tested 3D velocity models generally capture well long-period(<0.2 Hz)waveforms,indicating that the 3D models adequately resolve overall large-scale subsurface ***,the 3D synthetics show discrepancies in higher frequencies(0.05–0.3 Hz)and the performance of the 3D velocity models varies from region to region,suggesting that smaller scale heterogeneities are not well *** shallow velocity structures(<10 km)can improve the waveform fitting,emphasizing the importance of incorporating shallow structures in waveform *** full-waveform tomography model shows a slighter better performance than the other models,especially for the body-waves,highlighting the advantages

关键词： Southwest China Seismic tomography models Shallow Structures Waveform simulation Model evaluation