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High Voltage 2024年第1期9卷 163-171页

作者： Li Cai yifeng Ke Wenchao Fan Ruisheng Yan Mi zhou Jianguo Wang Yadong Fan Engineering Research Center of Ministry of Education for Lightning Protection and Grounding Technology School of Electrical Engineering and AutomationWuhan UniversityWuhanChina

As the wind turbine height increases,the probability of multiple upward leaders flashes within the wind farm increases.In this study,an upward lightning flash containing 21 upward positive leaders(UPLs)initiated from different wind turbines in Zhangbei Wind Farm was analysed.The average speed of the UPLs was 1.2×10^(5) m/s,which mostly decreased to zero before reaching the cloud height.Only four UPLs developed to cloud height,with prolonged periods of bright light on three of them and with a minimum duration of 126 ms.A total of nine return strokes occurred on the other two dissipated leader channels,and the numbers of strokes on the two channels was six and three,respectively.The average interstroke interval for the return strokes was 10.5 ms.Most of these nine return strokes had peak currents smaller than 10 kA.The high-speed video frames confirmed that competition does exist between the UPLs,and the range of shielding effects increases as the height of the ULs increases.The effect of fan rotation on the initiation of upward leaders and the shielding effect between the wind turbines and upward leaders are discussed.

关键词： flash return initiated

Harmonic State Space Based Impedance Modeling and Virtual Impedance Based Stability Enhancement Control for LCC-HVDC Systems

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 287-298页

作者： yifeng Liu Xiaoping zhou Quan Chen Hanhang Yin Lerong Hong Hao Tian Ying Chen Siyuan Li the College of Electrical and Information Engineering Hunan UniversityChangsha 410082China the Zhejiang Magtron Intelligent Technology Limited Cooperation Jiaxing 314000China the State Grid Qianjiang Electric Power Company Qianjiang 433100China

Line commutated converter based high-voltage direct-current(LCC-HVDC)transmissions are prone to harmonic oscillation under weak grids.Impedance modeling is an effective method for assessing interaction stability.Firstly,this paper proposes an improved calculation method for the DC voltage and AC currents of commutation stations to address the complex linearization of the commutation process and constructs an overall harmonic state-space(HSS)model of an LCC-HVDC.Based on the HSS model,the closed-loop AC impedances on the LCC-HVDC sending and receiving ends are then derived and verified.The impedance characteristics of the LCC-HVDC are then analyzed to provide a physical explanation for the harmonic oscillation of the system.The effects of the grid strength and control parameters on system stability are also analyzed.To improve the impedance characteristics and operating stability of the LCC-HVDC system,a virtual impedance based stability enhancement control is proposed,and a parameter design method is considered to ensure satisfactory phase margins at both the sending and receiving ends.Finally,simulation results are presented to verify the validity of the impedance model and virtual impedance based stability enhancement control.

关键词： Line commutated converter based high-voltage direct-current(LCC-HVDC)transmission harmonic state space stability analysis harmonic oscillation virtual impedance

A novel mutation of glycogen synthase kinase-3β leads to a reduced level of GSK3βprotein in a patient with dilated cardiomyopathy

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Genes & Diseases 2024年第1期11卷 84-86页

作者： Ke Gong Zhiping Tan Haidan Liu Xiaobo Liao Xinmin zhou Bangliang Yin Shi Zeng Yao Yao yifeng Yang Li Xie Department of Cardiovascular Surgery The Second Xiangya Hospital of Central South UniversityCentral South UniversityChangshaHunan410011China Department of Ultrasound The Second Xiangya Hospital of Central South UniversityCentral South UniversityChangshaHunan 410011China Department of Blood Transfusion The Second Xiangya Hospital of Central South UniversityCentral South UniversityChangshaHunan 410011China

Dilated cardiomyopathy(DCM)is a frequently inherited heart condition.A familial transmission rate of 20%-35%has been documented,and most of these cases are autosomal dominant.This condition has a high rate of morbidit... 详细信息

关键词： GSK3β cardiomyopathy mortality

An improved interval model updating method via adaptive Kriging models

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 497-514页

作者： Sha WEI yifeng CHEN Hu DING Liqun CHEN Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechanoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China Shanghai Institute of Aircraft Mechanics and Control Shanghai 200092China

Interval model updating(IMU)methods have been widely used in uncertain model updating due to their low requirements for sample data.However,the surrogate model in IMU methods mostly adopts the one-time construction method.This makes the accuracy of the surrogate model highly dependent on the experience of users and affects the accuracy of IMU methods.Therefore,an improved IMU method via the adaptive Kriging models is proposed.This method transforms the objective function of the IMU problem into two deterministic global optimization problems about the upper bound and the interval diameter through universal grey numbers.These optimization problems are addressed through the adaptive Kriging models and the particle swarm optimization(PSO)method to quantify the uncertain parameters,and the IMU is accomplished.During the construction of these adaptive Kriging models,the sample space is gridded according to sensitivity information.Local sampling is then performed in key subspaces based on the maximum mean square error(MMSE)criterion.The interval division coefficient and random sampling coefficient are adaptively adjusted without human interference until the model meets accuracy requirements.The effectiveness of the proposed method is demonstrated by a numerical example of a three-degree-of-freedom mass-spring system and an experimental example of a butted cylindrical shell.The results show that the updated results of the interval model are in good agreement with the experimental results.

关键词： interval model updating(IMU) non-probabilistic uncertainty adaptive Kriging model surrogate model grey number

Nickel-Catalyzed Regiodivergent Acylzincation of Styrenes with Organozincs and CO

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Chinese Journal of Chemistry 2024年第6期42卷 599-604页

作者： Chenglong Wang Ning Liu Xianqing Wu Jingping Qu yifeng Chen Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CenterFrontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237 China Dedicated to the Special Issue of C1 Chemistry.

Transition metal-catalyzed carbometallation of unsaturated hydrocarbons constitutes one of the most efficient synthetic methodologies for the construction of C—C bond.Recently,the incorporation of organometallic reagent with the CO gas as a nucleophilic acyl synthon could enable the acylmetallation reaction,which greatly increases the horizon of carbometallation chemistry.Herein,we report a nickel-catalyzed regiodivergent acylzincation of o-cyano cinnamate ester and o-cyano styrene,in which the cyano moiety intramolecularly captures zinc intermediates to trigger the tandem cyclization process.This protocol features mild conditions,broad substrate scope and excellent functional group tolerance,thus affording a diverse array of highly functionalized carbocyclic compounds.

关键词： Carbonylation Carbometallation Styrene Nickel Cyclization

Unravelling the genetic basis for skeletal muscle mitochondrial DNA copy number variations in pigs

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Science China(Life Sciences) 2024年第1期67卷 211-214页

作者： Jiawen Yang Leilei Cui yifeng Zhang Ziqi Ling zhou Zhang Yizhong Huang Junwu Ma Shijun Xiao Bin Yang Lusheng Huang National Key Laboratory for Swine Genetic Improvement and Germplasm Innovation Jiangxi Agricultural UniversityNanchang 330045China School of Life Sciences Nanchang UniversityNanchang 330047China

Dear Editor,Mitochondria are the center of cellular energy generation and free radical metabolism,with important functions in regulating intracellular calcium levels,cell apoptosis,cell cycle and epigenetic modifications.Mitochondrial DNA copy number(mtDNA-CN)is an indicator of mitochondrial biogenesis and has been associated with several diseases,such as cardiovascular disease,depression,chronic kidney disease and aging in humans(Clyde,2022).

关键词： metabolism cardiovascular diseases

Fabrication of micro-nano patterned materials mimicking the topological structure of extracellular matrix for biomedical applications

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Nano Research 2024年第5期17卷 4244-4258页

作者： yifeng Nie Dong Han Xiang Li CAS Center for Excellence in Nanoscience National Center for Nanoscience and TechnologyBeijing 100190China School of Future Technology University of Chinese Academy of SciencesBeijing 100049China

With the advent of tissue engineering and biomedicine,the creation of extracellular matrix(ECM)biomaterials for in vitro applications has become a prominent and promising strategy.These ECM materials provide physical,biochemical,and mechanical properties that guide cellular behaviors,such as proliferation,differentiation,migration,and apoptosis.Because micro-and nano-patterned materials have a unique surface topology and low energy replication process that directly affect cellular biological behaviors at the interface,the fabrication of micro-nano pattern biomaterials and the regulation of surface physical and chemical properties are of great significance in the fields of cell regulation,tissue engineering,and regenerative medicine.Herein,we provide a comprehensive review of the progress in the fabrication and application of patterned materials based on the coupling of mechanical action at the micro-and nano-meter scale,including photolithography,micro-contact printing,electron beam lithography,electrospinning,and 3D printing technology.Furthermore,a summary of the fabrication process,underlying principles,as well as the advantages and disadvantages of various technologies are reviewed.We also discuss the influence of material properties on the fabrication of micro-and nano-patterns.

关键词： micro/nano hybrid materials patterning fabrication techniques extracellular matrix substrate-cell interaction biomedical engineering

Electroactivity of the magnetotactic bacteria Magnetospirillum magneticum AMB-1 and Magnetospirillum gryphiswaldense MSR-1

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Frontiers of Environmental Science & Engineering 2024年第4期18卷 103-110页

作者： Mathias Fessler Qingxian Su Marlene Mark Jensen yifeng Zhang Department of Environmental and Resource Engineering Technical University of DenmarkCopenhagenDK-2800Denmark

Magnetotactic bacteria reside in sediments and stratified water columns.They are named after their ability to synthesize internal magnetic particles that allow them to align and swim along the Earth’s magnetic field lines.Here,we show that two magnetotactic species,Magnetospirillum magneticum strain AMB-1 and Magnetospirillum gryphiswaldense strain MSR-1,are electroactive.Both M.magneticum and M.gryphiswaldense were able to generate current in microbial fuel cells with maximum power densities of 27 and 11μW/m^(2),respectively.In the presence of the electron shuttle resazurin both species were able to reduce the crystalline iron oxide hematite(Fe_(2)O_(3)).In addition,M.magneticum could reduce poorly crystalline iron oxide(FeOOH).Our study adds M.magneticum and M.gryphiswaldense to the growing list of known electroactive bacteria,and implies that electroactivity might be common for bacteria within the Magnetospirillum genus.

关键词： Magnetotactic bacteria Magnetospirillum magneticum Magnetospirillum gryphiswaldense Extracellular electron transfer Microbial fuel cells

Continuous,efficient and safe synthesis of 1-oxa-2-azaspiro[2.5]octane in a microreaction system

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Chinese Journal of Chemical Engineering 2023年第9期61卷 37-42页

作者： Jinpei Huang Xingwei Lu Xuejing Zhang Yiqiang Jin yifeng zhou College of Life Science China Jiliang UniversityHangzhou 310018China Apeloa Pharmaceutical Co. Ltd.Dongyang 322118China

1-Oxa-2-azaspiro[2.5]octane,as one of N-H oxaziridines,is a selective electrophilic aminating agent for N-,S-,C-,and O-nucleophiles.It has the features of stereoselectivity and the absence of formation of strongly acidic or basic byproducts,leading to considerable interest in the development of organic synthetic methods.Currently,the economically feasible route of production of 1-oxa-2-azaspiro[2.5]octane is the reaction of cyclohexanone with ammonia and sodium hypochlorite.However,due to strong exothermic reactions,massive gas release and heterogeneous reaction,the controllability,efficiency and safety of the reaction are in great difficulty using batch technology.In this paper,a microreaction system containing predispersion,reaction and phase separation was introduced into the preparation of 1-oxa-2-azaspiro[2.5]octane.The research results showed that precise control of the process including droplet dispersion,temperature control,reaction time control and fast continuous phase separation,was the key to process intensification.Under optimal conditions,the concentration of 1-oxa-2-azaspiro[2.5]octane in product obtained by microreaciton system(~2.0 mol·L^(-1))was much higher than that obtained by batch technology(0.2-0.4 mol·L^(-1)),which demonstrated that the continuous-flow synthesis would be a more efficient substitute for batch synthesis.Meanwhile,the results of the derivation experiments also showed that the aminating agent solution with higher concentration was more advantageous in the applications.

关键词： Multiphase reaction Microreactor Synthesis Oxaziridine Process intensification

Fu-Zheng-Yi-Liu Formula inhibits the stem cells and metastasis of prostate cancer via tumor-associated macrophages/C-C motif chemokine ligand 5 pathway in tumor microenvironment

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Chinese Journal of Natural Medicines 2024年第6期22卷 501-514页

作者： CHEN Chiwei HUANG Renlun WANG Neng ZHENG yifeng zhou Jianfu YANG Bowen WANG Xuan ZHANG Juping PAN Bo CHEN Zhiqiang WANG Shengqi WANG Zhiyu XIANG Songtao The Research Center of Integrative Cancer Medicine Discipline of Integrated Chinese and Western Medicinethe Second Clinical College of Guangzhou University of Chinese MedicineGuangzhou 510000China The First Clinical College of Guangzhou University of Chinese Medicine Guangzhou 510000China Guangdong Provincial Key Laboratory of Clinical Research on Traditional Chinese Medicine Syndrome Guangdong Provincial Academy of Chinese Medical SciencesGuangdong Provincial Hospital of Chinese MedicineGuangzhou 510000China Guangdong-Hong Kong-Macao Joint Lab on Chinese Medicine and Immune Disease Research Guangzhou University of Chinese MedicineGuangzhou 510000China The Research Center for Integrative Medicine School of Basic Medical SciencesGuangzhou University of Chinese MedicineGuangzhou 510000China State Key Laboratory of Dampness Syndrome of Chinese Medicine The Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou 510000China

Prostate cancer(PCa)is the second most common malignancy among men globally.The Fu-Zheng-Yi-Liu(FZYL)Formula has been widely utilized in the treatment of PCa.This study investigates whether the FZYL Formula can inhibit PCa by tar-geting the TAMs/CCL5 pathway.We conducted in vitro co-cultures and in vivo co-injections of PCa cells and TAMs to mimic their in-teraction.Results showed that the FZYL Formula significantly reduced the proliferation,colony formation,subpopulations of PCSCs,and sphere-formation efficacy of PCa cells,even in the presence of TAM co-culture.Additionally,the Formula markedly decreased the migration,invasion,and epithelial-mesenchymal transition(EMT)of PCa cells induced by TAMs.The FZYL Formula also reversed M2 phenotype polarization in TAMs and dose-dependently reduced their CCL5 expression and secretion,with minimal cytotoxicity observed.Mechanistic studies confirmed that the TAMs/CCL5 axis is a critical target of the FZYL Formula,as the addition of exogen-ous CCL5 partially reversed the formula’s inhibitory effects on PCSCs self-renewal in the co-culture system.Importantly,the Formula also significantly inhibited the growth of PCa xenografts,bone metastasis,and PCSCs activity in vivo by targeting the TAMs/CCL5 pathway.Overall,this study not only elucidates the immunomodulatory mechanism of the FZYL Formula in PCa therapy but also highlights the TAMs/CCL5 axis as a promising therapeutic target.

关键词： Traditional Chinese medicine Tumor-associated macrophages Prostate cancer stem cells CCL5 Tumor microenvironment