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Anti-inflammatory germacrane-type sesquiterpene lactones from Vernonia sylvatica

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Chinese Journal of Natural Medicines 2024年第6期22卷 568-576页

作者： WANG Min LI han HU Bintao TANG Chunping xu Hui KE Changqiang XIE Zuoquan YE Yang YAO sheng State Key Laboratory of Drug Research&Natural Products Research Center Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China University of Chinese Academy of Sciences Beijing 100049China School of Life Science and Technology Shanghai Tech UniversityShanghai 201210China State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China Zhongshan Institute for Drug Discovery Shanghai Institute of Materia MedicaChinese Academy of SciencesZhongshan 528400China

Nine new germacranolides,sylvaticalides A−H(1-9),and three known analogues(10-12)were isolated from the aeri-al part of Vernonia *** structures were established using comprehensive spectroscopic analysis,including high-resolution electrospray ionization mass spectroscopy(HR-ESI-MS)and 1D and 2D nuclear magnetic resonance(NMR)*** absolute configurations were determined by X-ray diffraction *** anti-inflammatory activities of all isolated compounds were as-sessed by evaluating their inhibitory effects on the nuclear factor kappa B(NF-κB)pathway,which was activated by lipopolysacchar-ide(LPS)-stimulated human THP1-Dual cells,and the interferon-stimulated gene(ISG)pathway,activated by STING agonist MSA-2 in the same cell *** 1,2 and 6 showed inhibitory effects on the NF-κB and ISG signaling pathways,with IC_(50)values ranging from 4.12 to 10.57μmol·L^(−1).

关键词： Vernonia sylvatica Germacrane-type sesquiterpene lactone Sylvaticalides A−H Anti-inflammatory NF-κB path-way ISG pathway

Transverse mode-coupling instability with longitudinal impedance

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Nuclear Science and Techniques 2024年第6期35卷 40-53页

作者： Hai-sheng xu Chun-Tao Lin Na Wang Jing-Ye xu Yuan Zhang Key Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Institute of Advanced Science Facilities Shenzhen 518107GuangdongChina

Transverse mode-coupling instability(TMCI)is a dangerous transverse single-bunch instability that can lead to severe par-ticle *** mechanism of TMCI can be explained by the coupling of transverse coherent oscillation modes owing to the transverse short-range wakefield(i.e.,the transverse broadband impedance).Recent studies on future circular colliders,e.g.,FCC-ee,showed that the threshold of TMCI decreased significantly when both longitudinal and transverse impedances were *** performed computations for the circular electron-positron collider(CEPC)and observed a similar *** studies on the influence of longitudinal impedance on the TMCI threshold were *** concluded that the imaginary part of the longitudinal impedance,which caused a reduction in the incoherent synchrotron tune,was the primary reason for the reduction in the TMCI ***,the real part of the longitudinal impedance assists in increasing the TMCI threshold.

关键词： Transverse mode-coupling instability Longitudinal impedance

Effects of nitrogen deposition on the carbon budget and water stress in Central Asia under climate change

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Journal of Arid Land 2024年第8期16卷 1118-1129页

作者： han Qifei xu Wei LI Chaofan School of Geographical Sciences Nanjing University of Information Science&TechnologyNanjing 210044China

Atmospheric deposition of nitrogen(N)plays a significant role in shaping the structure and functioning of various terrestrial ecosystems ***,the magnitude of N deposition on grassland ecosystems in Central Asia still remains highly *** this study,a multi-data approach was adopted to analyze the distribution and amplitude of N deposition effects in Central Asia from 1979 to 2014 using a process-based denitrification decomposition(DNDC)*** showed that total vegetation carbon(C)in Central Asia was 0.35(±0.09)Pg C/a and the averaged water stress index(WSI)was 0.20(±0.02)for the whole *** N deposition led to an increase in the vegetation C of 65.56(±83.03)Tg C and slightly decreased water stress in Central *** of this study will expand both our understanding and predictive capacity of C characteristics under future increases in N deposition,and also serve as a valuable reference for decision-making regarding water resources management and climate change mitigation in arid and semi-arid areas globally.

关键词： carbon dynamics climate change grassland ecosystems nitrogen deposition water stress index

Single-Nucleus RNA Sequencing Reveals Cardiac Macrophage Landscape in Hypoplastic Left Heart Syndrome

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Congenital Heart Disease 2024年第2期19卷 233-246页

作者： Xiaozhuo xu Yilin Huang xu han First Clinical Medical College Affiliated Hospital of Nanjing University of Chinese MedicineNanjing210008China Department of Geriatrics Affiliated Hospital of Nanjing University of Chinese MedicineNanjing210029China

Background:Hypoplastic left heart syndrome(HLHS)is one of the most challenging congenital heart diseases in clinical *** cardiac tissues,resident macrophages fulfill critical functions in maintaining a stable cardiac state and have strong regenerative capacity and organ ***,the molecular mechanisms of macro-phages in HLHS remained ***:Single-nucleus RNA sequencing(snRNA-seq)data of HLHS and healthy control(donors)samples obtained from the Gene Expression Omnibus(GEO)database were normalized and clustered using the Seurat ***“FindMarkers”function was used to screen differentially expressed genes(DEGs)between the HLHS and donor groups and to analyze the functional enrichment of the set of genes of ***,cell-cell communication,pseudotime,and single-cell regulatory network inference and cluster-ing(SCENIC)analyses were used to study the mechanisms of macrophages in ***:Based on the snRNA-seq data of HLHS and donors,we identified a total of 9 cell clusters,among which the proportion of macrophages was significantly less in the HLHS group than in the control *** of macrophage subpopulations(Macrophages 1,2,and 3)showed that Macrophages 1 was mainly involved in nervous system development,angiogenesis,and apoptotic *** addition,analysis of communication between Macro-phages 1 and cardiomyocytes revealed that ligand-acceptor pairs such as GAS6/AXL,IL6,IGF1,THY1,and L1CAM were present only in the donor ***,pesudotime and SCENIC analyses demonstrated that FOXO3 and ELF2 played a critical role for Macrophages 1 to maintain cardiac function in patients with ***:Our study improved the current understanding of the molecular mechanisms of macrophage devel-opment in HLHS,showing that manipulating the regulatory role of macrophages in the heart can be a novel treat-ment for HLHS.

关键词： Hypoplastic left heart syndrome single-nucleus RNA sequencing macrophage cellular subpopulation transcription factor

Molecular dynamics study of hydrogen-induced cracking behavior of ferrite–pearlite gas transmission pipeline steel

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Journal of Iron and Steel Research International 2024年第2期31卷 488-500页

作者： Tao-long xu Si-han Guo Gong-zhen He Hao-yu han Petroleum Engineering School Southwest Petroleum UniversityChengdu610500SichuanChina Sichuan East Gas Transmission Sales Center of Sinopec Natural Gas Branch Wuhan430074HubeiChina

Hydrogen embrittlement of pipelines depends on the hydrogen-induced cracking behavior of the pipeline steel *** on molecular dynamics analysis,the ferrite–cementite(α-Fe/Fe3C)lamellar atomic structure with the Bagaryatskii orientation relationship was established,and stepwise relaxation of the conjugate gradient energy minimization and constant-temperature and constant-pressure relaxation were performed under NPT(the isothermal–isobaric)*** mechanical property curves of theα-Fe/Fe3C models were obtained under different cementite terminal plane structures,and the evolution of the atomic structure was analyzed in *** addition,the influence of different hydrogen concentrations,different temperatures,different strain rates,changes in voids,and different micro-degrees of freedom on the deformation and failure mechanism of the model was investigated,aiming to provide a reliable way to explore the micro-mechanism of macro-cracking behavior of pipeline steel.

关键词： Ferrite-cementite lamellar structure Pipeline steel Failure mechanism Crack propagation Molecular dynamics

Enhanced corrosion resistance of epoxy resin coating via addition of CeO_(2) and benzotriazole

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Chinese Journal of Chemical Engineering 2024年第3期67卷 89-96页

作者： xu han Ruijie Guo Baolong Niu Hong Yan College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China

The use of fillers to enhance the corrosion protection of epoxy resins has been widely *** this work,cerium dioxide(CeO_(2))and benzotriazole(BTA)were introduced into an epoxy resin to enhance the corrosion resistance of Q235 carbon *** electron microscopy results indicated that the CeO_(2) grains were rod-like and ellipsoidal in shape,and the distribution pattern of BTA was analyzed by energy dispersive *** dynamic potential polarization curve proved the excellent corrosion resistance of the composite epoxy resin with CeO_(2) and BTA co-addition,and electrochemical impedance spectroscopy test analysis indicated the significantly enhanced long-term corrosion protection performance of the composite *** the optimal protective performance was provided by the coating containing 0.3%(mass)CeO_(2) and 20%(mass)BTA,which was attributed to the barrier performance of CeO_(2) particles and the chemical barrier effect of *** formation of corrosion products was analyzed using X-ray *** addition,the corrosion resistance mechanism of the coating was also discussed in detail.

关键词： Benzotriazole Cerium dioxide Corrosion resistance Carbon steel Epoxy resin coating Preparation

Simulation study on the security of consensus algorithms in DAG-based distributed ledger

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Frontiers of Computer Science 2024年第3期18卷 171-182页

作者： Shuzhe LI Hongwei xu Qiong LI Qi han Faculty of Computing Harbin Institute of TechnologyHarbin 150001China

Due to the advantages of high volume of transactions and low resource consumption,Directed Acyclic Graph(DAG)-based Distributed Ledger Technology(DLT)has been considered a possible next-generation alternative to ***,the security of the DAG-based system has yet to be comprehensively *** at verifying and evaluating the security of DAG-based DLT,we develop a Multi-Agent based IOTA Simulation platform called *** MAIOTASim,we model honest and malicious nodes and simulate the configurable network environment,including network topology and *** double-spending attack is a particular security issue related to *** perform the security verification of the consensus algorithms under multiple double-spending attack *** simulations show that the consensus algorithms can resist the parasite chain attack and partially resist the splitting attack,but they are ineffective under the large weight *** take the cumulative weight difference of transactions as the evaluation criterion and analyze the effect of different consensus algorithms with parameters under each attack ***,MAIOTASim enables users to perform largescale simulations with multiple nodes and tens of thousands of transactions more efficiently than state-of-the-art ones.

关键词： distributed ledger IOTA Multi-Agent system simulation

Perception of fundamental science to boost lithium metal anodes toward practical application

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Green Energy & Environment 2024年第3期9卷 454-472页

作者： Jinkun Wang Li Wang Hong xu Li sheng Xiangming He Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing100084China

As a key material for lithium metal batteries(LMBs),lithium metal is one of the most promising anode materials to break the bottleneck of battery energy density and a commonly used active material for reference *** lithium anodes are regarded as the holy grail of lithium batteries,decades of exploration have not led to the successful commercialization of LMBs,due mainly to the challenges related to the inherent properties of lithium *** pave the way for further investigation,herein,a comprehensive review focusing on the fundamental science of lithium are ***,the natures of lithium atoms and their isotopes,lithium clusters and lithium crystals are revisited,especially their structural and energetic ***,the electrochemical properties of lithium metal are *** important concepts and scientific questions,including the electronic structure of lithium,influence of high pressure and low temperature on the properties of lithium,factors influencing lithium deposition,generation of lithium dendrites,and electrode potential of lithium in different electrolytes,are explained and analyzed in *** to improve the performance of lithium anodes and thoughtfulness about the electrode potential in lithium battery research are proposed.

关键词： Lithium Cluster Crystal Physicochemical property Fundamental science

Electrochemical Mono-Deuterodefluorination of Trifluoromethyl Aromatic Compounds with Deuterium Oxide

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CCS Chemistry 2024年第1期6卷 230-240页

作者： Jie sheng xu Cheng Institute of Chemistry and Biomedical Sciences Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023 State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 30071

The deuterodifluoromethyl group CF_(2)D combines the structural features of CF_(3) and CD_(3) groups,finding wide applications in diverse pharmaceutical *** this work,the electrochemical monodeuterodefluorination of Ar-CF_(3) to Ar-CF_(2)D is achieved with an unreported deuterium atom transfer-coupled electron transfer pathway using D_(2)O as the only D source for the first time.A series of Ar-CF_(3) substances,including commercial pharmaceuticals,were converted to corresponding CF_(2)D products in up to 91% yield and 97% D-incorporation.A variety of functional groups,including pyridine,pyrrole,furan,thiophene,borate,thio ether,amine,amide,sulfonamide,and halide,are well tolerated in this protocol.t-BuOLi was an essential reagent to achieve chemoselective mono-defluorination.

关键词： electrochemistry C-F activation fluorinecontaining drugs deuterated drugs deuterium oxide