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Activities of Daily Living-Related Functional Impairment Among Population Aged 65 and Older—China,2011–2050

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China CDC weekly 2023年第27期5卷 593-598页

作者： Binbin Su Panliang Zhong Chen Chen yu wu Xiaoying zheng School of Population Medicine and Public Health Chinese Academy of Medical Sciences/Peking Union Medical CollegeBeijingChina Department of Population Health and Aging Science School of Population Medicine and Public HealthChinese Academy of Medical Sciences/Peking Union Medical CollegeBeijingChina

Summary What is already known about this topic?The elevated prevalence of functional impairment among elderly individuals in China contributes to an increased burden of care.What is added by this report?This report presents a comprehensive evaluation of trends in functional impairment related to activities of daily living(ADL)among the elderly population in China.Furthermore,it offers insights for future projections of these trends in this demographic group.What are the implications for public health practice?Addressing the care needs and functional impairment issues among the aging population in China necessitates interdepartmental collaboration.

关键词： Population demographic elderly

GPU-enhanced DEM analysis of flow behaviour of irregularly shaped particles in a full-scale twin screw granulator

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Particuology 2022年第2期20卷 30-40页

作者： Chao zheng Nicolin Govender Ling Zhang Chuan-yu wu Department of Chemical and Process Engineering University of SurreyGuildford GU27XHUnited Kingdom Department of Mechanical Engineering University of JohannesburgSouth Africa Research Center Pharmaceutical Engineering GmbH Graz 8010Austria

During twin screw granulation(TSG),small particles,which generally have irregular shapes,agglomerate together to form larger granules with improved properties.However,how particle shape impacts the conveying characteristics during TSG is not explored nor well understood.In this study,a graphic processor units(GPUs)enhanced discrete element method(DEM)is adopted to examine the effect of particle shape on the conveying characteristics in a full scale twin screw granulator for the first time.It is found that TSG with spherical particles has the smallest particle retention number,mean residence time,and power consumption;while for TSG with hexagonal prism(Hexp)shaped particles the largest particle retention number is obtained,and TSG with cubic particles requires the highest power consumption.Furthermore,spherical particles exhibit a flow pattern closer to an ideal plug flow,while cubic particles present a flow pattern approaching a perfect mixing.It is demonstrated that the GPU-enhanced DEM is capable of simulating the complex TSG process in a full-scale twin screw granulator with non-spherical particles.

关键词： Discrete element method Twin screw granulation Non-spherical particle Residence time distribution GPU

An atmosphere-breathing propulsion system using inductively coupled plasma source

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Chinese Journal of Aeronautics 2023年第5期36卷 223-238页

作者： Peng zheng Jianjun wu yu ZHANG Bixuan CHE yuanzheng ZHAO College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

CubeSats have attracted more research interest recently due to their lower cost and shorter production time.A promising technology for CubeSat application is atmosphere-breathing electric propulsion,which can capture the atmospheric particles as propulsion propellant to maintain longterm mission at very low Earth orbit.This paper designs an atmosphere-breathing electric propulsion system for a 3 U CubeSat,which consists of an intake device and an electric thruster based on the inductively coupled plasma.The capture performance of intake device is optimized considering both particles capture efficiency and compression ratio.The plasma source is also analyzed by experiment and simulation.Then,the thrust performance is also estimated when taking into account the intake performance.The results show that it is feasible to use atmosphere-breathing electric propulsion technology for CubeSats to compensate for aerodynamic drag at lower Earth orbit.

关键词： Atmosphere-Breathing Electric Propulsion(ABEP) CubeSat Inductively coupled plasma Intake device Very Low Earth Orbit(VLEO)

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Stoichiometric Imbalance-promoted Step-growth Polymerization Based on Self-accelerating Three-component Reaction

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Chemical Research in Chinese Universities 2023年第5期39卷 822-828页

作者： ZHANG yu zheng Jianzhi LI Xijuan wu Ying ZHANG Ke Institute of Polymer Chemistry and Physics Beijing Key Laboratory of Energy Conversion and Storage MaterialsCollege of ChemistryBeijing Normal UniversityBeijing 100875P.R.China Laboratory of Polymer Physics and Chemistry Institute of ChemistryChinese Academy of SciencesBeijing 100190P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

Aself-accelerating three-component reaction was developed using the secondary amines,CS_(2),and sym-dibenzo-1,5-cyclooctadiene-3,7-diyne(DIBOD)as reactants.In this three-component reaction,the secondary amine reacts with CS_(2) to form dithiocarbamate anion,which subsequently in-situ reacts with DIBOD behaving a self-accelerating reaction property.Specifically,the reaction of dithiocarbamate anion with the first alkyne of DIBOD activates the unreacted alkyne,which reacts with dithiocarbamate anion much faster than the original alkyne of DIBOD.Using the self-accelerating three-component reaction as polymerization reaction,a stoichiometric imbalance-promoted step-growth polymerization method was developed using the difunctional secondary amines,CS_(2),and DIBOD as monomer groups.This novel three-component polymerization can quickly produce high molecular weight dithiocarbamate-containing polymers under mild conditions using a slight molar excess of DIBOD to difunctional secondary amine monomer.Containing sulfur elements in the backbones,the resultant polymers hold high refractivity and may find potential applications in optical and optoelectronic fields.

关键词： Self-accelerating three component reaction Stoichiometric imbalance-promoted three component polymerization Dithiocarbamate-containing polymer

A new species of the genus Amolops(Anura:Ranidae)from yunnan,China

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Zoological Research 2020年第2期41卷 188-193页

作者： yu-Lu Gan Guo-Hua yu zheng-Jun wu Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection(Guangxi Normal University) Ministry of EducationGuilinGuangxi 541004China Guangxi Key Laboratory of Rare and Endangered Animal Ecology College of Life ScienceGuangxi Normal UniversityGuilinGuangxi 541004China

DEAR EDITOR,A new species of the genus Amolops,Amolops tuanjieensis sp.nov.,is described from yunnan,China.The new species can be distinguished by the following characters:dorsolateral folds present;dorsal and ventral surfaces smooth;top of head and dorsum brown-red with irregular gray and dark spots;flank green;side of head black,from tip of snout,diffusing posteriorly to axilla,continuing as black streak below edge of dorsolateral fold;SVL 39.5-40.4 mm in males,56.8-60.7 mm in females;tympanum distinct;supratympanic fold indistinct;vomerine teeth in two oblique rows between choanae,closer to each other than choanae;vocal sacs present;nuptial pads present;outer metatarsal tubercle absent,supernumerary tubercles absent;all fingertips expanded into discs;limbs dorsally brown with dark brown bars and irregular dark brown blotches.

关键词： black closer brown

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Changing Patterns of Heart Disease Mortality in Rural and Urban Areas—China,1987–2021

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China CDC weekly 2023年第14期5卷 306-310页

作者： Binbin Su Panliang Zhong yu wu Yaohua Tian Xiaoying zheng School of Population Medicine and Public Health Chinese Academy of Medical Sciences/Peking Union Medical CollegeBeijingChina Ministry of Education Key Laboratory of Environment and Health and State Key Laboratory of Environmental Health(Incubating)School of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhan CityHubei ProvinceChina

Heart disease(HD)is an important component of the spectrum of cardiovascular diseases(CVDs).China has the highest number of new HD cases in the world(1),posing significant health and economic burdens to society.However,its mortality trends at the national level and urban-rural differences remain unclear.This study,which identifies the age,period,and cohort effects of HD mortality trend changes,would assist the government in understanding future trends and optimizing public health policies.The HD mortality data by age,gender,and region were extracted from China’s National Health Commission’s death registration system,after quality control of ID and duplicate removal(2).The age-standardized mortality rate was calculated based on the world standard population using the direct method.Joinpoint regression was employed to determine HD mortality change patterns across time(3).The age-period-cohort model was used to estimate cohort and period effects(4).In this model,age refers to the individual’s age at a given time,period refers to the time at which the outcome is measured,and cohort refers to the group of individuals born in a particular period.This study revealed that HD mortality in China has rapidly increased over the past two decades,with men increasing faster than women and rural areas increasing faster than urban areas.

关键词： mortality cardiovascular diseases

Electrochemically-mediated C-H functionalization of allenes and 1,3-dicarbonyl compounds to construct tetrasubstituted furans

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Organic Chemistry Frontiers 2022年第3期9卷 781-787页

作者： Mu-Xue He Yan Yao Chun-Zhi Ai Zu-yu Mo Yu-Zheng Wu Qi Zhou Ying-Ming Pan Hao-Tao Tang State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541004China School of Public Health Guilin Medical UniversityGuilin 541004China Pharmacy School Guilin Medical UniversityGuilin 541004China Adesis Inc.A Universal Display company New CastleDelaware 19720USA

C-H functionalization of allenes is an available strategy to construct heterocyclic compounds.Herein we propose a sus-tainable electrocatalytic C-H activation for the synthesis of novel highly functionalized tetrasubs... 详细信息

关键词： compounds substituted furan

Enhanced thermal isolation in porous thermal barrier coatings by the formation of pore guided thermal-shock cracks

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Science China(Technological Sciences) 2023年第4期66卷 1007-1017页

作者： ZHEN yu wu KaiJin LIU MengQi zheng SongLin HE LingHui yu Yin NI Yong CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsCAS Center for Excellence in Complex System MechanicsUniversity of Science and Technology of ChinaHefei 230026China National Key Laboratory of Shock Wave and Detonation Physics China Academy of Engineering PhysicsInstitute of Fluid PhysicsMianyang 621900China

Pore structure design is an effective strategy to tailor the thermal isolation capability of thermal barrier coatings(TBCs).Pursuing optimal porosity is crucial to balance the requirements of thermal isolation and mechanical reliability since the pore structure shields thermal heat transfer but increases mechanical degradation.In this work,we investigate how thermal heat transfer couples with fracture propagation in porous TBCs by the using thermo-mechanical coupling phase field model for fracture.The simulated results show that cracks induced by thermal shock favor deflection that is sometimes perpendicular to the direction of heat flow.The thermal conductivity degradation by the transverse cracks significantly impedes thermal heat transfer,leads to enhanced reduction of the effective thermal conductivity of TBCs,decreases the average thermal stress of the substrate,and thus decreases the risk of the crack penetrating into the substrate.The numerical results demonstrate that the phase field method fully considering the thermo-mechanical interaction between cracks and pores can be a useful tool to improve the thermal isolation of porous TBCs under extreme thermal shock loadings through pore structure design.

关键词： phasefield TBCs porosity thermal shock cracks

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Uniquely identifying topological order based on boundary-bulk duality and anyon condensation

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National Science Review 2023年第3期10卷 117-126页

作者： Yong-Ju Hai Ze Zhang Hao zheng Liang Kong Jiansheng wu Dapeng yu Shenzhen Institute for Quantum Science and Engineering Southern University of Science and Technology Department of Physics Southern University of Science and Technology International Quantum Academy Guangdong Provincial Key Laboratory of Quantum Science and Engineering

Topological order is a new quantum phase that is beyond Landau’ s symmetry-bre aking paradigm.Its defining features include robust degenerate ground states,long-range entanglement and anyons.It was known that R and F matrices,which characterize the fusion-braiding properties of anyons,can be used to uniquely identify topological order.In this article,we explore an essential question:how can the R and F matrices be experimentally measured?We show that the braidings,i.***.the R matrices,can be completely determined by the half braidings of boundary excitations due to the boundary-bulk duality and the anyon condensation.The F matrices can also be measured by comparing the quantum states involving the fusion of three anyons in two different orders.Thus we provide a model-independent experimental protocol to uniquely identify topological order.By using quantum simulations based on a toric code model with boundaries encoded in three-and four-qubit systems and state-of-the-art technology,we obtain the first experimental measurement of R and F matrices by means of an NMR quantum computer at room temperature.

关键词： topological order R matrix F matrix bulk-boundary duality anyon condensation