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A Global Optimality Principle for Fully Coupled Mean-field Control Systems

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 379-413页

作者： tao HAO School of Statistics and Mathematics Shandong University of Finance and EconomicsJinan 250014China

This paper concerns a global optimality principle for fully coupled mean-field control *** the first-order and the second-order variational equations are fully coupled mean-field linear FBSDEs. A new linear relation is introduced, with which we successfully decouple the fully coupled first-order variational equations. We give a new second-order expansion of y^(ε) that can work well in mean-field framework. Based on this result, the stochastic maximum principle is proved. The comparison with the stochastic maximum principle for controlled mean-field stochastic differential equations is supplied.

关键词： optimal control global maximum principle fully coupled general mean-field FBSDE adjoint equation recursive utility

Relative Broken Family Sensitivity

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2297-2306页

作者： Zhuo Wei LIU tao yU Department of Mathematics Shantou UniversityShantou 515063P.R.China

Letπ:(X,T)→(y,S)be a factor map between two topological dynamical systems,and F_(a) Furstenberg family of *** introduce the notion of relative broken *** Fs(***,Finf)be the families consisting of all syndetic subsets(*** upper Banach density subsets,infinite subsets).We show that for a factor mapπ:(X,T)→(y,S)between transitive systems,πis relatively broken F-sensitive for F=Fs or Fpubd if and only if there exists a relative sensitive pair which is an F-recurrent point of(R_(π),T^((2)));is relatively broken Finf-sensitive if and only if there exists a relative sensitive pair which is not *** a factor mapπ:(X,T)→(y,S)between minimal systems,we get the structure of relative broken F-sensitivity by the factor map to its maximal equicontinuous factor.

关键词： Relative sensitivity recurrent points Furstenberg family relative sensitive pairs maximal equicontinuous factor

Evolutionary history shapes variation of wood density of tree species across the world

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Plant Diversity 2024年第3期46卷 283-293页

作者： Fangbing Li Hong Qian Jordi Sardans Dzhamal y.Amishev Zixuan Wang Changyue Zhang Tonggui Wu Xiaoniu Xu Xiao tao Xingzhao Huang Anhui Province Key Laboratory of Forest Resources and Silviculture Anhui Agricultural UniversityHefei 230036China State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou 311300China Research and Collections Center Illinois State Museum1011 East Ash StreetSpringfieldIL 62703USA CREAF Cerdanyola del VallesBarcelona 08193Spain Global Ecology Unit CREAF-CSIC-UAB CSICBellaterraBarcelona 08193Spain Key Laboratory of Ecosystem Carbon Source and Sink China Meteorological Administration(ECSS-CMA)School of Applied MeteorologyNanjing University of Information Science&Technology219 Ningliu RoadNanjing 210044China Department of natural Resources Management Lakehead UniversityThunder BayOntario P7B 5E1Canada School of Forestry&Landscape of Architecture Anhui Agricultural UniversityHefei 230036China Research Institute of Subtropical Forestry Chinese Academy of ForestryHangzhou 311400China

The effect of evolutionary history on wood density variation may play an important role in shaping variation in wood density,but this has largely not been *** a comprehensive global dataset including 27,297 measurements of wood density from 2621 tree species worldwide,we test the hypothesis that the legacy of evolutionary history plays an important role in driving the variation of wood density among tree *** assessed phylogenetic signal in different taxonomic(e.g.,angiosperms and gymnosperms)and ecological(e.g.,tropical,temperate,and boreal)groups of tree species,explored the biogeographical and phylogenetic patterns of wood density,and quantified the relative importance of current environmental factors(e.g.,climatic and soil variables)and evolutionary history(i.e.,phylogenetic relatedness among species and lineages)in driving global wood density *** found that wood density displayed a significant phylogenetic *** density differed among different biomes and climatic zones,with higher mean values of wood density in relatively drier regions(highest in subtropical desert).Our study revealed that at a global scale,for angiosperms and gymnosperms combined,phylogeny and species(representing the variance explained by taxonomy and not direct explained by long-term evolution process)explained 84.3%and 7.7%of total wood density variation,respectively,whereas current environment explained 2.7%of total wood density variation when phylogeny and species were taken into *** angiosperms and gymnosperms were considered separately,the three proportions of explained variation are,respectively,84.2%,7.5%and 6.7%for angiosperms,and 45.7%,21.3%and 18.6%for *** study shows that evolutionary history outpaced current environmental factors in shaping global variation in wood density.

关键词： Wood density Phylogeny Angiosperms Gymnosperms Climate factors Biophysical parameters

Exploring the impacts of major events on the systemic risk of the international energy market

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Petroleum Science 2024年第2期21卷 1444-1457页

作者： Ming-tao Zhao Su-Wan Lu Lian-Biao Cui School of Statistics and Applied Mathematics Anhui University of Finance and EconomicsBengbu233030AnhuiChina Anhui Province Key Laboratory of Philosophy and Social Science of Low-Carbon Development and Carbon Finance Anhui University of Finance and EconomicsBengbu233030AnhuiChina

This study examines the systemic risk caused by major events in the international energy market(IEM)and proposes a management strategy to mitigate it. Using the tail-event driven network(TEnET)method, this study constructed a tail-risk spillover network(TRSn) of IEM and simulated the dynamic spillover tail-risk process through the cascading failure mechanism. The study found that renewable energy markets contributed more to systemic risk during the Paris Agreement and the COVID-19pandemic, while fossil energy markets played a larger role during the Russia-Ukraine conflict. This study identifies systemically important markets(SM) and critical tail-risk spillover paths as potential sources of systemic risk. The research confirms that cutting off the IEM risk spillover path can greatly reduce systemic risk and the influence of SM. This study offers insights into the management of systemic risk in IEM and provides policy recommendations to reduce the impact of shock events.

关键词： International energy market Tail-risk spillover Cascading failure mechanism Systemic risk management

Pairing nitroxyl radical and phenazine with electron-withdrawing/-donating substituents in “water-in-ionic liquid” for high-voltage aqueous redox flow batteries

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Green Energy & Environment 2024年第4期9卷 713-722页

作者： Zhifeng Huang Rolf Hempelmann yiqiong Zhang Li tao Ruiyong Chen Transfercenter Sustainable Electrochemistry Saarland University and KIST Europe66125SaarbruckenGermany State Key Laboratory of Chem/Bio-Sensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University Changsha410082HunanChina College of Materials Science and Engineering Changsha University of Science and Technology Changsha410114HunanChina Materials Innovation Factory Department of ChemistryUniversity of LiverpoolLiverpoolL697ZDUnited Kingdom

Aqueous redox-active organic materials-base electrolytes are sustainable alternatives to vanadium-based electrolyte for redoxﬂow batteries(RFBs)due to the advantages of high ionic conductivity,environmentally benign,safety and low ***,the underexplored redox properties of organic materials and the narrow thermodynamic electrolysis window of water(1.23 V)hinder their wide ***,seeking suitable organic redox couples and aqueous electrolytes with a high output voltage is highly suggested for advancing the aqueous organic *** this work,the functionalized phenazine and nitroxyl radical with electron-donating and electron-withdrawing group exhibit redox potential of-0.88 V and 0.78 V ***,respectively,in“water-in-ionic liquid”supporting *** spectra reveal that the activity of water is largely suppressed in“water-in-ionic liquid”due to the enhanced hydrogen bond interactions between ionic liquid and water,enabling an electrochemical stability window above 3 V.“Water-in-ionic liquid”supporting electrolytes help to shift redox potential of nitroxyl radical and enable the redox activity of functionalized *** assembled aqueous RFB allows a theoretical cell voltage of 1.66 V and shows a practical discharge voltage of 1.5 V in the“water-in-ionic liquid”***,capacity retention of 99.91%per cycle is achieved over 500 charge/discharge cycles.A power density of 112 mW cm^(-2) is obtained at a current density of 30 mA cm^(-2).This work highlights the importance of rationally combining supporting electrolytes and organic molecules to achieve high-voltage aqueous RFBs.

关键词： Aqueous redoxﬂow batteries Water-in-ionic liquid electrolytes High-voltage aqueous batteries Organic redox-active materials

Increasing operational stability of journal bearing in hydraulic suspension micro-pump by herringbone grooved structure

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Science China(Technological Sciences) 2024年第3期67卷 853-862页

作者： HOnG tao XInG Guanying ZUO Huaiyu XUE Song LUO XiaoBing State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The operational stability of radial journal bearings is the bottleneck that limits the reliability of hydraulic suspension micropump. Due to self-excited vibrations, the whirl amplitude of the plain journal bearing(PJB) is large at high rotational speeds,which will accelerate wear failure. It has been proven that employing herringbone grooved journal bearing(HGJB) is an effective method to reduce the whirl amplitude and improve operational stability. However, enhancing the stability of journal bearings in micro-pumps by herringbone grooved structures has rarely been studied, and its effect needs to be verified. We validated the mechanism of the stability improvement with the CFD method and compared the dynamic characteristics of HGJB and PJB by rotor dynamics evaluation and experiment. The experimental results show that under the same conditions the whirl amplitude of the HGJB decreases by 29.61% in the x direction and by 24.09% in the y direction compared with that of the PJB. This study reveals the effect of the herringbone grooved structure on the operational stability of bearings and may provide guidance for the reliability improvement of hydraulic suspension micro-pump.

关键词： journal bearing herringbone groove hydrodynamic effect micro-pump

Three rare anti-inflammatory sesquiterpene lactones from Magnolia grandiflora

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Chinese Journal of natural Medicines 2024年第3期22卷 265-272页

作者： XU Shuangyu ZHAnG Feng tao Linlan JIAnG yangming HUAnG tao LI yanan HU Zhanxing yAnG Jue HAO Xiaojiang yUAn Chunmao State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical UniversityGuiyang 550014China School of Pharmaceutical Sciences Guizhou Medical UniversityGuiyang 550025China natural Products Research Center of Guizhou Province Guiyang 550014China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China

Four new sesquiterpene lactones(SLs)(1–4),along with a biosynthetically related SL(5),have been isolated from the leaves of Magnolia *** A(1)is notable as the first C18 homogemarane type SL,featuring a unique 1,7-dioxaspiro[4.4]nonan-6-one *** 2 and 3,representing the first instances of chlorine-substituted gemarane-type SL analogs in natural products,were also *** structures of these isolates were elucidated through a combination of spectroscopic data analysis,electronic circular dichroism calculations,and X-ray single-crystal diffraction *** isolates demonstrated anti-inflammatory activity in lipopolysaccharide-stimulated RAW264.7 ***,3–5 showed a significant inhibitory effect on nitric oxide production,with IC50 values ranging from 0.79 to 4.73μmol·L^(−1).Additionally,4 and 5 exhibited moderate cytotoxic activities against three cancer cell lines,with IC50 values between 3.09 and 11.23μmol·L^(−1).

关键词： Magnolia grandiflora Sesquiterpene lactones Isolation and identification Anti-inflammatory activity

Fli1 acts in parallel with Pu.1 to control macrophage and neutrophil fate in zebrafish

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Journal of Genetics and Genomics 2024年第3期51卷 359-362页

作者： Ao Zhang Jingao Lu Shachuan Feng Huapeng yu tao yu Shizheng Zhao Kemin Chen Zhibin Huang Jin Xu Jianan y.Qu Zilong Wen Division of Life Science Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina Division of Cell Developmental and Integrative BiologySchool of MedicineSouth China University of TechnologyGuangzhouGuangdong 510006China Department of Immunology and Microbiology School of Life ScienceSouthern University of Science and TechnologyShenzhenGuangdong 518055China Biomedical Research Institute Shenzhen Peking University-Hong Kong University of Science and Technology Medical CenterShenzhenGuangdong 518036China Department of Electronic and Computer Engineering Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina Greater Bay Biomedical Innocenter Shenzhen Bay LaboratoryShenzhenGuangdong 518067China

Macrophages and neutrophils are key components of myeloid cells and play critical roles in innate immune responses,organ formation,and tissue *** integrity of their functions heavily relies on the generation of a proper number of mature macrophages and neutrophils through embryonic and adult *** mammalian adult myelopoiesis,oligopotent common myeloid progenitors(CMPs)are known to be the earliest myeloid progenitors,which give rise to granulocyte-macrophage progenitors(GMPs),subsequently differentiate into unipotent neutrophil and macrophage precursors,and finally,mature macrophages and neutrophils(Orkin and Zon,2008).In contrast,the ontogeny of embryonic myelopoiesis and the mechanism underlying the formation of macrophages and neutrophils remainless understood.

关键词： fish macrophage homeostasis

Porous high-entropy rare-earth phosphate(REPO_(4),RE=La,Sm,Eu,Ce,Pr and Gd)ceramics with excellent thermal insulation performance via pore structure tailoring

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1651-1658页

作者： Peixiong Zhang Enhui Wang Jingjing Liu tao yang Hailong Wang Xinmei Hou Institute for Carbon neutrality University of Science and Technology BeijingBeijing 100083China Liaoning Academy of Materials Shenyang 110000China Technical Support Center for Prevention and Control of Disastrous Accidents in Metal Smelting University of Science and Technology BeijingBeijing 100083China School of Materials Science Engineering Zhengzhou UniversityZhengzhou 450001China

Thermal insulation materials play an increasingly important role in protecting mechanical parts functioning at high *** this study,a new porous high-entropy(La_(1/6)Ce_(1/6)Pr_(1/6)Sm_(1/6)Eu_(1/6)Gd_(1/6))PO_(4)(HE(6RE_(1/6))PO_(4))ceramics was prepared by combining the high-entropy method with the pore-forming agent method and the effect of different starch contents(0–60vol%)on this ceramic properties was systematically *** results show that the porous HE(6RE_(1/6))PO_(4)ceramics with 60vol%starch exhibit the lowest thermal conductivity of 0.061 W·m^(-1)·K^(-1)at room temperature and good pore structure stability with a linear shrinkage of approximately1.67%.Moreover,the effect of large regular spherical pores(>10μm)on its thermal insulation performance was discussed,and an optimal thermal conductivity prediction model was *** superior properties of the prepared porous HE(6RE_(1/6))PO_(4)ceramics allow them to be promising insulation materials in the future.

关键词： porous high-entropy(La_(1/6)Ce_(1/6)Pr_(1/6)Sm_(1/6)Eu_(1/6)Gd_(1/6))PO_(4) ceramics high-entropy strategy pore-forming agent method thermal insulation material thermal conductivity