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Science China Chemistry 2024年第7期67卷 2306-2313页

作者： Dong-Yue Cai Weiming Shi zhao-Hui jin Zhi-Xiang Yu jin-xin zhao Jian-Min Yue State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China University of Chinese Academy of Sciences Beijing 100049China Beijing National Laboratory for Molecular Sciences(BNLMS) Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of ChemistryPeking UniversityBeijing 100871China

Mimicking biosynthetic pathways of hongkonoids led to the development of a new Cu(Ⅰ)-catalyzed[3+2]cycloaddition ofα-hydroxyketone andβ-keto enol ethers,affording tetrahydrofuran acetals in a highly diastereoselective manner and 100%atom economy.Computational studies on the mechanism disclosed a concerted but asynchronous Michael addition/aldol reaction.Of the same importance,this methodology provides a practical biomimetic approach for one-step construction of the dibenzylbutyrolactol lignan backbone starting from two phenyl propane derivatives,opening up a powerful new approach for lignan synthesis,which is showcased by succinct total syntheses of two biologically important aryltetralin-type lignans,β-apopicropodophyllin and cycloolivil.Given the mild and operationally simple conditions,the developed chemistry might have a promising prospect in potential industrial applications.

关键词： [3+2]cycloaddition transition-metal catalysis tetrahydrofuran lignans natural products

Frontier studies on natural products:moving toward paradigm shifts

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Science China Chemistry 2023年第4期66卷 928-942页

作者： jin-xin zhao Jian-Min Yue State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China Shandong Laboratory of Yantai Drug Discovery Bohai Rim Advanced Research Institute for Drug DiscoveryYantai 264117China

1 Introduction Natural products(NPs)historically serve as a valuable and productive source of bioactive compounds for drug development.The discovery of a range of alkaloids in the early1800s,including strychnine,morph... 详细信息

关键词： alkaloids moving compounds

Cephalotane-Type Norditerpenoids from Cephalotaxus fortunei var.alpina

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Chinese Journal of Chemistry 2022年第10期40卷 1177-1184页

作者： Zhan-Peng Ge Bin Zhou Flavia M.Zimbres Maria B.Cassera jin-xin zhao Jian-Min Yue State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of Sciences555 Zuchongzhi RoadShanghai 201203China Department of Biochemistry and Molecular Biology Center for Tropical and Emerging Global Diseases(CTEGD)University of GeorgiaAthensGeorgia30602UnitedStates

A chemical investigation of the 95%EtoH extract of the seeds of Cephalotaxus fortunei var.alpina led to the isolation of nine new cephalotane-type norditerpenoids,ceforalides A-I(1-9),and two known analogues(10 and 11).Compounds 1-8 belong to a rare class of A-ring-contracted cephalotane-type norditerpenoids,of which compound 8 incorporates a unique tetrasubstituted 2,5-cyclohexadienone A-ring.Compound 9 is a rare 13,14-seco-17-nor-cephalotane-type diterpenoid.Their structures were determined based on NMR,HRESIMS,ECD,and X-ray diffraction analysis.Biological tests revealed compounds 10 and 11 displayed moderate antimalarial activity.

关键词： Cephalotaxus fortunei var.alpine Natural products Structural elucidation Cephalotane norditerpenoids I Antimalarial activity

Design strategies of high-performance lead-free electroceramics for energy storage applications

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Rare Metals 2024年第3期43卷 853-878页

作者： Biao Guo Fei jin Li Li Zi-zhao Pan xin-Wei Xu Hong Wang Department of Materials Science and Engineering College of EngineeringSouthern University of Science and TechnologyShenzhen518055China School of Microelectronics and State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an710049China

A greater number of compact and reliable electrostatic capacitors are in demand due to the Internet of Things boom and rapidly growing complex and integrated electronic systems,continuously promoting the development of high-energy-density ceramic-based capacitors.Although significant successes have been achieved in obtaining high energy densities in lead-based ferroelectric ceramics,the utilization of lead-containing ceramies has been restricted due to environmental and health hazards of lead.Lead-free ferroelectric ceramics have garnered tremendous attention and are expected to replace lead-based ceramics in the near future.However,the energy density of lead-free ceramics is still lagging behind that of lead-containing cou.nterparts,severely limiting their applications.Significant efforts have been made to enhance the energy storage performance of lead-free ceramics using multi-scale design strategies,and exciting progress has been achieved in the past decade.This review briefly discusses the energy storage mechanism and fundamental characteristics of a dielectric capacitor,summarizes and compares the state-of-the-art design strategies for high-energy-density lead-free ceramics,and highlights several critical issues and requirements for industrial production.The prospects and challenges of lead-free ceramics for energy storage applications are also discussed.

关键词： Dielectric materials Lead-free ceramic Environment friendly Energy storage Design strategy

A sub-grid scale model for Burgers turbulence based on the artificial neuralnetwork method

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Theoretical & Applied Mechanics Letters 2024年第3期14卷 162-165页

作者： xin zhao Kaiyi Yin Department of Mechanics Beijing Institute of TechnologyBeijing 100081China

The present study proposes a sub-grid scale model for the one-dimensional Burgers turbulence based on the neuralnetwork and deep learning method.The filtered data of the direct numerical simulation is used to establish thetraining data set,the validation data set,and the test data set.The artificial neural network(ANN)methodand Back Propagation method are employed to train parameters in the ANN.The developed ANN is applied toconstruct the sub-grid scale model for the large eddy simulation of the Burgers turbulence in the one-dimensionalspace.The proposed model well predicts the time correlation and the space correlation of the Burgers turbulence.

关键词： Artificial neural network Back propagation method Burgers turbulence Large eddy simulation Sub-grid scale model

Principal components of nuclear mass models

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 65-71页

作者： xin-Hui Wu Pengwei zhao Department of Physics Fuzhou UniversityFuzhou 350108China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China

Principal component analysis(PCA)is employed to extract the principal components(PCs)present in nuclear mass models for the first time.The effects from different nuclear mass models are reintegrated and reorganized in the extracted PCs.These PCs are recombined to build new mass models,which achieve better accuracy than the original theoretical mass models.This comparison indicates that using the PCA approach,the effects contained in different mass models can be collaborated to improve nuclear mass predictions.

关键词： nuclear mass principal component analysis nuclear models statistical methods

Successful management of severe hypoglycemia induced by total parenteral nutrition in patients with hepatocellular injury: Three cases reports

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World Journal of Clinical Cases 2024年第1期12卷 157-162页

作者： Ling-Zhi Fang Hui-xin jin Na zhao Yu-Pei Wu Ying-Qin Shi Department of Pharmacy Hebei Key Laboratory of Clinical PharmacyHebei General HospitalShijiazhuang 050051Hebei ProvinceChina

BACKGROUND Glucose imbalance is common in total parenteral nutrition(TPN).Hypoglycemia seems to be less frequent than hyperglycemia,but it influences the clinical outcome to a greater extent.Therefore,it should be effectively prevented and treated.However,there is no relevant report on how to treat hypoglycemia caused by TPN in patients with liver cell injury.CASE SUMMARY We present three patients with liver cell injury who developed severe hypo-glycemia during or after TPN infusion.The causes of severe hypoglycemia and glucose-raising strategies were discussed.According to the physiological charac-teristics of the hepatocellular injury,the ratio of nutrition components prescribed in TPN was appropriately adjusted for the three cases.We simultaneously reduced the dose of insulin and fat emulsion,and increased the dose of glucose in TPN.The blood glucose level was restored to normal range and clinical symptoms were eliminated.CONCLUSION When hypoglycemia occurs during or after TPN in patients with hepatocellular injury,physicians need to simultaneously reduce insulin and fat emulsion,and increase glucose,and correct severe hypoglycemia in time to reduce its adverse consequences.

关键词： Total parenteral nutrition Hepatocellular injury Severe hypoglycemia Treatment Causes Case report

Online diagnosis platform for tomato seedling diseases in greenhouse production

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 80-89页

作者： xin jin Xiaowu Zhu Jiangtao Ji Mingyong Li Xiaolin Xie Bo zhao College of Agricultural Equipment Engineering Henan University of Science and TechnologyLuoyang 471003HenanChina Science&Technology Innovation Center for Completed Set Equipment Longmen LaboratoryLuoyang 471023HenanChina Institute of Mechatronics Technology and Application China Mechanized Agriculture Science Research Institute Group Co.LtdBeijing 100020China

The facility-based production method is an important stage in the development of modern agriculture,lifting natural light and temperature restrictions and helping to improve agricultural production efficiency.To address the problems of difficulty and low accuracy in detecting pests and diseases in the dense production environment of tomato facilities,an online diagnosis platform for tomato plant diseases based on deep learning and cluster fusion was proposed by collecting images of eight major prevalent pests and diseases during the growing period of tomatoes in a facility-based environment.The diagnostic platform consists of three main parts:pest and disease information detection,clustering and decision-making of detection results,and platform diagnostic display.Firstly,based on the You Only Look Once(YOLO)algorithm,the key information of the disease was extracted by adding attention module(CBAM),multi-scale feature fusion was performed using weighted bi-directional feature pyramid network(BiFPN),and the overall construction was designed to be compressed and lightweight;Secondly,the k-means clustering algorithm is used to fuse with the deep learning results to output pest identification decision values to further improve the accuracy of identification applications;Finally,a detection platform was designed and developed using Python,including the front-end,back-end,and database of the system to realize online diagnosis and interaction of tomato plant pests and diseases.The experiment shows that the algorithm detects tomato plant diseases and insect pests with mAP(mean Average Precision)of 92.7%,weights of 12.8 Megabyte(M),inference time of 33.6 ms.Compared with the current mainstream single-stage detection series algorithms,the improved algorithm model has achieved better performance;The accuracy rate of the platform diagnosis output pests and diseases information of 91.2%for images and 95.2%for videos.It is a great significance to tomato pest control research and the development of smart agriculture.

关键词： pest and disease detection YOLO diagnosis platform k-means clustering facility production base

Current status of liver transplantation for human immunodeficiency virus-infected patients in China's Mainland

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World Journal of Gastroenterology 2024年第14期30卷 1958-1962页

作者： Jian-xin Tang Dong zhao Department of Liver Surgery and Organ Transplantation Center Shenzhen Third People’s HospitalThe Second Affiliated Hospital of Southern University of Science and TechnologyNational Clinical Research Center for Infectious DiseaseShenzhen 518000Guangdong ProvinceChina

According to the report from the Chinese Center for Disease Control and Prevention,the prevalence of human immunodeficiency virus(HIV)infection exceeded 1.2 million individuals by the year 2022,with an annual increase of about 80000 cases.The overall prevalence of hepatitis B surface antigen among individuals co-infected with HIV reached 13.7%,almost twice the rate of the general population in China.In addition to the well-documented susceptibility to opportunistic infections and new malignancies,HIV infected patients frequently experience liver-related organ damage,with the liver and kidneys being the most commonly affected.This often leads to the development of end-stage liver and kidney diseases.Therefore,organ transplantation has emerged as an important part of active treatment for HIV infected patients.However,the curative effect is not satisfactory.HIV infection has been considered a contraindication for organ transplantation.Until the emergence of highly active anti-retroviral therapy in 1996,the once intractable replication of retrovirus was effectively inhibited.With prolonged survival,the failure of important organs has become the main cause of death among HIV patients.Therefore,transplant centers worldwide have resu-med exploration of organ transplantation for HIV-infected individuals and reached a positive conclusion.This study provides an overview of the current landscape of HIV-positive patients receiving liver transplantation(LT)in main-land China.To date,our transplant center has conducted LT for eight end-stage liver disease patients co-infected with HIV,and all but one,who died two months postoperatively due to sepsis and progressive multi-organ failure,have survived.Comparative analysis with hepatitis B virus-infected patients during the same period revealed no statistically significant differences in acute rejection reactions,cytomegalovirus infection,bacteremia,pulmonary infections,acute kidney injury,new-onset cancers,or vascular and biliary complications.

关键词： Liver transplantation Human immunodeficiency virus Infection Hepatitis B virus End-stage liver disease China'Mainland

Efficacy and safety of triple-antiplatelet therapy after percutaneous coronary intervention： a meta-analysis

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Chinese Medical Journal 2013年第9期126卷 1750-1754页

作者： ZHANG Yong TANG Hai-qin LI jin FU zhao-xin Department of Geriatrics First Affiliated Hospital of Anhui Medical University Hefei Anhui 230022 China

Background The combination of cilostazol, aspirin and clopidogrel （triple antiplatelet therapy, TAT） after a percutaneous coronary intervention has been used as an alternative therapy. We performed a meta-analysis to evaluate the efficacy and safety of TAT for patients after percutaneous coronary intervention （PCI）. Methods We systematically searched Pubmed, Embase and Web of Science databases to identify all randomized controlled trials （RCTs） that compared dual antiplatelet therapy （DAT） with and without cilostazol after PCI. All analyses were conducted using Review Manager 5.0. Results The final analysis consisted of 4474 patients from ten studies. The combined results suggested that there was a lower risk of cardiac death （relative risk （RR）=0.55, 95% confidence interval （Cl）： 0.31-0.98, P 〈0.05） and major adverse cardiac events （MACEs）（RR=0.63, 95% Cl： 0.54-0.74, P 〈0.05） in patients treated with TAT as compared to those with DAT follow-ups after six months to one year; no significant difference was observed in bleeding and non-fatal myocardial infarction （MI）（RR=1.14, 95% Cl： 0.80-1.64, P 〉0.055 RR=0.87, 95% Cl： 0.42-1.83, P 〉0.05）. However, the rate of adverse drug reaction was higher in patients receiving TAT than in patients receiving DAT （RR=2.21, 95% Cl： 1.84-2.66, P 〈0.05）. Moreover, there was a lower risk of stent thrombosis in patients treated with TAT as compared to those treated with DAT （RR=0.44, 95% Cl： 0.21-0.94, P 〈0.05）. The TAT group had a reduced risk of target lesion revascularization （TLR）（RR=0.60, 95% Cl： 0.43-0.82, P=-0.001） and target vessel revascularization （TVR） than the DAT group （RR=0.56, 95% Cl： 0.45-0.71, P 〈0.05）. The number of MACEs was lower for patients in the TAT group than in the DAT group with diabetes mellitus sub-analysis （RR=0.41, 95% Cl： 0.28-0.61, P 〈0.05）. But no significant difference was observed between the two groups regarding MACEs in patients with drug-eluting stent implantations （RR=0.82, 95% Cl： 0.65-1.03, P 〉0.05）. Conclusion TAT could significantly redu

关键词： triple antiplatelet therapy dual antiplatelet therapy percutaneous coronary intervention meta-analysis