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Mapping the spatial and temporal patterns of fallow land in mountainous regions of China

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International Journal of Digital Earth 2022年第1期15卷 2148-2167页

作者： Wen Song Alexander V.Prishchepov Wei song Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingPeople’s Republic of China School of Geomatics and Urban Spatial Informatics Beijing University of Civil Engineering and ArchitectureBeijingPeople’s Republic of China Department of Geosciences and Natural Resource Management (IGN) University of CopenhagenKøbenhavn KDenmark Department of Theoretical Cybernetics and Applied Mathematics Altai State UniversityBarnaulRussia

The rapid growth of the global population has resulted in a continuous increase in cropland intensity and a shortening of the fallow period as part of the cropland rotation cycle.Yet,there is a lack of systematic knowledge on the extent of fallow lands,particularly in complex landscapes,such as the mountainous regions of China.To fill this knowledge gap,taking Yuanyang County(YYC),Yunnan Province,China,as a case study,we tested a method to identify the spatial-temporal distribution of fallow land by mapping cropland with Landsat data.The overall accuracy of land cover classification,including cropland,ranged between 90.1%and 95.8%from 1998 to 2019.The average accuracy of fallow plots was 75.7%from 2001 to 2019.The annual fallow rate varied between 8.3%and 54.3%,with an average of 20.7%.Kernel density estimated with the probability density function showed that fallow varied between 5 and 13 blocks per km2,gradually decreasing from the central area to the periphery.Increasing elevation,the low value of regional domestic products,and the increased distance to rural settlements were closely related to the higher proportions of fallow land.The approach presented here can be applied to map fallow land in other regions.

关键词： Remote sensing fallow land kernel density time series China

Design Strategies for Aqueous Zinc Metal Batteries with High Zinc Utilization: From Metal Anodes to Anode-Free Structures

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Nano-Micro Letters 2024年第4期16卷 305-349页

作者： Xianfu Zhang Long Zhang Xinyuan Jia Wen Song Yongchang Liu School of Materials Science and Engineering University of Science and Technology Beijing30 College RoadBeijing 100083People’s Republic of China Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyState Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083People’s Republic of China

Aqueous zinc metal batteries(AZMBs)are promising candidates for next-generation energy storage due to the excellent safety, environmental friendliness, natural abundance, high theoretical specific capacity, and low redox potential of zinc(Zn) metal. However,several issues such as dendrite formation, hydrogen evolution, corrosion, and passivation of Zn metal anodes cause irreversible loss of the active materials. To solve these issues, researchers often use large amounts of excess Zn to ensure a continuous supply of active materials for Zn anodes. This leads to the ultralow utilization of Zn anodes and squanders the high energy density of AZMBs. Herein, the design strategies for AZMBs with high Zn utilization are discussed in depth, from utilizing thinner Zn foils to constructing anode-free structures with theoretical Zn utilization of 100%, which provides comprehensive guidelines for further research. Representative methods for calculating the depth of discharge of Zn anodes with different structures are first summarized. The reasonable modification strategies of Zn foil anodes, current collectors with pre-deposited Zn, and anode-free aqueous Zn metal batteries(AF-AZMBs) to improve Zn utilization are then detailed. In particular, the working mechanism of AF-AZMBs is systematically introduced. Finally, the challenges and perspectives for constructing high-utilization Zn anodes are presented.

关键词： Aqueous zinc metal batteries Zinc anodes High zinc utilization Depth of discharge Anode-free structures

6-DOF Motion Assessment of A Hydrodynamic Numerical Simulation of A Semisubmersible Platform Using Prototype Monitoring Data

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China Ocean Engineering 2022年第4期36卷 575-587页

作者： LI song WU wen-hua YAO Wei-an Faculty of Vehicle Engineering and Mechanics Dalian University of TechnologyDalian 116024China State Key Laboratory of Structural Analysis of Industrial Equipment Dalian University of TechnologyDalian 116024China Research Institute of Dalian University of Technology in Shenzhen Gaoxin South fourth Road Nanshan DistrictShenzhen 518057China

Hydrodynamic numerical simulations are used to conduct structural analyses and inform the design of engineered marine structures.In this paper,a hydrodynamic numerical model of“Nanhai Tiaozhan”(NHTZ)FPS platform was established according to its design specifications.The model was assessed with two sets of field monitoring data representing harsh and conventional sea states.The motion responses of the platform according to the measured data and the hydrodynamic simulation were compared by reviewing their statistical characteristics,distributions,and spectrum characteristics.The comparison showed that the hydrodynamic model could correctly simulate the frequency domain characteristics of the motion responses of the platform.However,the simulation underestimated the reciprocating motions of the floating body and the influence of slow drift on the motion of the platform.Meanwhile,analysis of the monitoring data revealed that the translational degrees of freedom(DOF)and rotational DOF of the platform were coupled,but these coupled motion states were not apparent in the hydrodynamic simulation.

关键词： prototype monitoring hydrodynamic numerical simulation statistical characteristics semisubmersible platform reciprocating motions

Financing the price-setting newsvendor with sales effort

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Journal of Management Analytics 2020年第4期7卷 564-590页

作者： wen Ding Huihui song Antai College of Economics&Management Shanghai Jiao Tong UniversityShanghaiPeople’s Republic of China

In this paper,we consider the financing issues in a supply chain where the capitalconstrained retailer should use limited funds to pay for both order and sales.The retailer decides the retail price,order quantity exante and sales effort expost,and he supports these operational activities by two financing sources:bank loan and trade credit.We illustrate that in this two-stage problem,the price-setting retailer’s equilibrium sales effort and retail price are both related to the market realization value and the retailer’s cash level.These two financing sources are both able to stimulate the retailer to promote sales.If the retailer’s cash level is reasonably high,both parties(supplier and retailer)benefit from trade credit.By contrast,if the retailer’s cash level is low,trade credit may discourage the retailer from sales promotion.Counterintuitively,our study shows that the retailer spends more on sales when the market is good than when it is bad.

关键词： Capital-constrained retailer sales effort trade credit bank loan pricesetting

Characteristics and Potential Roles of Natural Killer Cells During SARS-CoV-2 Infection

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Infectious Diseases & Immunity 2023年第1期3卷 29-35页

作者： wen-Jing Cao Fu-Sheng Wang Jin-Wen Song The First Affiliated Hospital of USTC Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui province 230001China Department of Infectious Diseases Fifth Medical Center of Chinese PLA General HospitalNational Clinical Research Center for Infectious DiseasesBeijing 100039China.

The emergence of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has caused a tremendous burden on public health and world economies.An efficient host immune response to acute SARS-CoV-2 infection requires rapid and early activation of the innate immune system.Natural killer(NK)cells represent a critical component of the innate immunity.Here,the appearance of CD56-CD16+NK cells and unconventional CD56^(dim) CD16^(neg) NK cells during the course of SARS-CoV-2 infection,and the phenotype and effector functions of NK cells during SARS-CoV-2 infection were summarized.The involvement of the dysregulated NK cells in the immunopathogenesis of the coronavirus disease 2019(COVID-19)and clinical trials of adoptive NK cell–based therapies against COVID-19 were also discussed.

关键词： Killer cells,natural Innate immunity SARS-CoV-2 Inflammation TGFβ Cell therapy

Experimental study on the mechanism of flow blockage formation in fast reactor

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Nuclear Science and Techniques 2023年第6期34卷 171-182页

作者： wen-Hui Jin song-Bai Cheng Xiao-Xing Liu Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai519082China

Various sources of solid particles might exist in the coolant flow of a liquid metal cooled fast reactor(e.g.,through chemical interaction between the coolant and impurities,air,or water,through corrosion of structural materials,or from damaged/molten fuel).Such particles may cause flow blockage accidents in a fuel assembly,resulting in a reduction in coolant flow,which potentially causes a local temperature rise in the fuel cladding,cladding failure,and fuel melt.To understand the blockage formation mechanism,in this study,a series of simulated experiments was conducted by releasing different solid particles from a release device into a reducer pipe using gravity.Through detailed analyses,the influence of various experimental parameters(e.g.,particle diameter,capacity,shape,and static friction coefficient,and the diameter and height of the particle release nozzle)on the blockage characteristics(i.e.,blockage probability and position)was examined.Under the current range of experimental conditions,the blockage was significantly influenced by the aforementioned parameters.The ratio between the particle diameter and outlet size of the reducer pipe might be one of the determining factors governing the occurrence of blockage.Specifically,increasing the ratio enhanced blockage(i.e.,larger probability and higher position within the reducer pipe).Increasing the particle size,particle capacity,particle static friction coefficient,and particle release nozzle diameter led to a rise in the blockage probability;however,increasing the particle release nozzle height had a downward influence on the blockage probability.Finally,blockage was more likely to occur in non-spherical particles case than that of spherical particles.This study provides a large experimental database to promote an understanding of the flow blockage mechanism and improve the validation process of fast reactor safety analysis codes.

关键词： Liquid metal cooled fast reactor Flow blockage Granular jamming Experimental study

Structural Insight into Recognition of Plant Peptid Hormones by Receptors

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Molecular Plant 2016年第11期9卷 1454-1463页

作者： Heqiao Zhang Zhifu Han Wen Song Jijie Chai Innovation Center for Structural Biology Tsinghua-Peking Joint Center for Life Sciences School of Life Sciences Tsinghua University Beijing 100084 China

Secreted signaling peptides or peptide hormones play crucial roles in plant growth and development through coordination of cell-cell communication. Perception of peptide hormones in plants generally relies on membrane-localized receptor kinases （RKs）. Progress has recently been made in structural elucidation of interactions between posttranslationally modified peptide hormones and RKs. The structural studies suggest conserved receptor binding and activation mechanisms of this type of peptide hormones involving their conserved C-termini. Here, we review these structural data and discuss how the conserved mecha- nisms can be used to match peptide-RK pairs.

关键词： peptide hormones small signaling peptides receptor kinases ligand recognition posttranslationalmodifications

Safety and immunogenicity of COVID-19 vaccination in immunocompromised patients

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Chinese Medical Journal 2022年第22期135卷 2656-2666页

作者： Jin-Wen Song Wei Hu Lili Shen Fu-Sheng Wang Senior Department of Infectious Diseases The Fifth Medical Center of Chinese PLA General HospitalNational Clinical Research Center for Infectious DiseasesBeijing 100039China Department of Emergency The Fifth Medical Center of Chinese PLA HospitalBeijing 100039China Department of Clinical Medicine Bengbu Medical CollegeBengbuAnhui 233030China

The coronavirus disease 2019(COVID-19)pandemic poses a great threat to public health.Individuals who are immunocompromised because of the progression of the primary disease or receiving immunosuppressive medications are prone to severe COVID-19 complications and poor outcomes.Abundant data have shown that many COVID-19 vaccines are safe and effective in large-scale populations;however,these clinical trials have excluded immunocompromised populations.Available evidence indicates that immunocompromised populations have a blunted immune response to other vaccines,raising concerns regarding the efficacy of COVID-19 vaccination in these populations.Thus,there is an urgent need to delineate the efficacy of COVID-19 vaccines in these vulnerable populations.Here,we review the characteristics of specific humoral and cellular responses to COVID-19 vaccination in immunocompromised populations,including HIV-infected patients and those receiving immunosuppressive treatment,especially solid organ transplant recipients and those undergoing anti-CD20 treatment.We also addressed the challenges that immunocompromised populations will face in the future pandemic and the need for basic and clinical translational studies to highlight the best vaccination strategies for these populations.

关键词： Anti-CD20 treatment Coronavirus disease 2019 Human immunodeficiency virus Immunocompromised Solid organ transplant recipient Vaccine

Lattice and spin dynamics in multiferroic BiFeO3 and RMnO3

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National Science Review 2019年第4期6卷 642-652页

作者： Yan song Ben Xu Ce-wen Nan School of Materials Science and Engineering and State Key Laboratory of New Ceramics and Fine ProcessingTsinghua University

The multiferroic materials Bi Fe O3 and RMn O3 exhibit coexisting magnetic order and ferroelectricity, and provide exciting platforms for new physics and potentially novel devices, where intriguing interplay between phonons and magnons exists. In this review, we paint a complete picture of bulk BiFeOtogether with orthorhombic and hexagonal RMnO(R includes rare-earth elements and yttrium) by summarizing the dynamics of spin and lattice and their magnetoelectric coupling, as well as the methods of controlling these characteristics under non-equilibrium conditions, from experimental and simulation perspectives.

关键词： multiferroics phonon magnon