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Modeling slow deformation of polygonal particles using DEM

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Particuology 2008年第6期6卷 506-514页

作者： Andrés A. Pea Pedro G. Lind hans j. herrmann Institute for Computational Physics Universitt Stuttgart Computational Physics IfB HIF E12 ETH Hnggerberg CH-8093 Zrich Switzerland Departamento de Física Universidade Federal do Ceará

We introduce two improvements in the numerical scheme to simulate collision and slow shearing of irregular particles. First, we propose an alternative approach based on simple relations to compute the frictional contact forces. The approach improves efficiency and accuracy of the Discrete Element Method （DEM） when modeling the dynamics of the granular packing. We determine the proper upper limit for the integration step in the standard numerical scheme using a wide range of material parameters. To this end, we study the kinetic energy decay in a stress controlled test between two particles. Second, we show that the usual way of defining the contact plane between two polygonal particles is, in general, not unique which leads to discontinuities in the direction of the contact plane while particles move. To solve this drawback, we introduce an accurate definition for the contact plane based on the shape of the overlap area between touching particles, which evolves continuously in time.

关键词： Granular media Discrete element method Slow deformation Contact forces

Neighbour effects on plant biomass and its allocation for forbs growing in heterogeneous soils

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j.urnal of Plant Ecology 2024年第4期17卷 90-99页

作者： Yongj.e Liu Chunyan Ma Shiting Liu Mingrui Liu Hui Li Mingxia Wang Guoe Li hans j.De Boeck Fuj.ang Hou Zhanhui Tang Zhenxin Li State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems Key Laboratory of Grassland Livestock Industry InnovationMinistry of Agriculture and Rural AffairsCollege of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730020China School of Ecology and Environmental Sciences Yunnan UniversityKunming 650091China Plant and Ecosystems(PLECO) Department of BiologyUniversity of AntwerpWilrijk B-2610Belgium State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration School of EnvironmentNortheast Normal UniversityChangchun 130117China Key Laboratory of Biodiversity and Environment on the Qinghai-Tibet Plateau Ministry of EducationLhasa 850011China

Focal plants are considerably affected by their neighbouring plants,especially when growing in heterogeneous soils.A previous study on grasses demonstrated that soil heterogeneity and species composition affected plant biomass and above-and belowground allocation *** now tested whether these findings were similar for *** forb species(*** anglica,Limonium bicolor and Suaeda glauca)were grown in pots with three levels of soil heterogeneity,created by alternatively filling resource-rich and resource-poor substrates using small,medium or large patch *** compositions were created by growing these forbs either in monocultures or in *** showed that patch size×species composition significantly impacted shoot biomass,root biomass and total biomass of forbs at different ***,at the pot scale,shoot biomass,root biomass and total biomass increased with increasing patch *** the substrate scale,shoot biomass and total biomass were higher at the large patch size than at the medium patch size,both in resource-rich and resource-poor ***,at the community scale,monocultures had more shoot biomass,root biomass and total biomass than those in the two-or three-species *** results differ from earlier findings on the responses of grasses,where shoot biomass and total biomass decreased with patch size,and more shoot biomass and total biomass were found in resource-rich than resource-poor *** further elucidate the effects of soil heterogeneity on the interactions between neighbour plants,we advise to conduct longer-term experiments featuring a variety of functional groups.

关键词： biomass allocation neighbour effect patch size soil heterogeneity shoot biomass

Older Adult Compendium of Physical Activities:Energy costs of human activities in adults aged 60 and older

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j.urnal of Sport and Health Science 2024年第1期13卷 13-17,F0003页

作者： Erik A.Willis Stephen D.herrmann Mary Hastert Chelsea L.Kracht Tiago V.Barreira j.hn M.Schuna j.. Zhenghua Cai Minghui Quan Scott A.Conger Wendy j.Brown Barbara E.Ainsworth Center for Health Promotion and Disease Prevention University of North Carolina at Chapel HillChapel HillNC 27599USA Kansas Center for Metabolism and Obesity Research The University of Kansas Medical CenterKansas CityKS 66160USA Division of Physical Activity and Weight Management Department of Internal MedicineUniversity of Kansas Medical CenterKansas CityKS 66160USA Clinical Science Division Pennington Biomedical Research CenterBaton RougeLA 70808USA Exercise Science Department Syracuse UniversitySyracuseNY 13244USA School of Exercise&Sport Science Oregon State UniversityCorvallisOR 97331USA School of Exercise and Health Shanghai University of SportShanghai 200438China Department of Kinesiology Boise State UniversityBoiseID 83725USA School of Human Movement and Nutrition Sciences The University of QueenslandSt.LuciaQLD 4072Australia Faculty of Health Sciences and Medicine Bond UniversityGold CoastQLD 4229Australia College of Health Solutions Arizona State UniversityPhoenixAZ 85003USA

Purpose:To describe the development of a Compendium for estimating the energy costs of activities in adults>60 years(OA Compendium).Methods:Physical activities(PAs)and their metabolic equivalent of task(MET)values were obtained from a systematic search of studies published in 4 sport and exercise databases(PubMed,Embase,SPORTDiscus(EBSCOhost),and Scopus)and a review of articles included in the 2011 Adult Compendium that measured PA in older *** values were computed as the oxygen cost(VO_(2),mL/kg/min)during PA divided by 2.7 m L/kg/min(MET_(60+))to account for the lower resting metabolic rate in older ***:We identified 68 articles and extracted energy expenditure data on 427 *** these,we derived 99 unique Specific Activity codes with corresponding MET_(60+)values for older *** developed a website to present the OA Compendium MET_(60+)values:https://***:The OA Compendium uses data collected from adults>60 years for more accurate estimation of the energy cost of PAs in older *** is an accessible resource that will allow researchers,educators,and practitioners to find MET_(60+)values for older adults for use in PA research and practice.

关键词： Energy expenditure Exercise MET Older adults

Chemically robust superhydrophobic surfaces with a self‐replenishing nanoscale liquid coating

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Droplet 2024年第1期3卷 136-148页

作者： Xiaoteng Zhou Pranav Sudersan Diego Diaz Benj.min Leibauer Chirag Hinduj. Fahimeh Darvish Pravash Bista Lukas Hauer Manfred Wagner Werner Steffen j.e Liu Michael Kappl hans‐j.rgen Butt Max Planck Institute for Polymer Research MainzGermany Key Laboratory of Green Printing Institute of ChemistryChinese Academy of SciencesBeijingChina School of Chemical Sciences University of Chinese Academy of SciencesBeijingChina

Due to poor chemical robustness,superhydrophobic surfaces become susceptible to failure,especially in a highly oxidative *** ensure the longterm efficacy of these surfaces,a more stable and environmentally friendly coating is required to replace the conventional salinization ***,soottemplated surfaces with re‐entrant nanostructures are precoated with polydimethylsiloxane(PDMS)*** additional nanometer‐thick lubricant layer of PDMS was then applied to increase chemical *** surface is superhydrophobic with a nanoscale liquid *** the lubricant layer is thin,ridge formation is suppressed,which leads to low drop sliding friction and fast drop *** introducing a bottom“reservoir”of a free lubricant as an oil source for self‐replenishing to the upper layer,the superhydrophobic surface becomes more stable and heals spontaneously in response to alkali erosion and O2 plasma *** design also leads to a higher icing delay time and faster removal of impacting cooled water drops than for uncoated surfaces,preventing icing at low temperatures.

关键词： coating friction liquid

Bound State Description of Particles from a Quantum Field Theory of Fermions and Bosons, Compatible with Relativity

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j.urnal of High Energy Physics, Gravitation and Cosmology 2024年第2期10卷 562-573页

作者： hans-Peter Morsch HOFF J&uumllich Germany

Both, the dilemma to find a quantum field theory consistent with Einstein’s law of relativity and the problem to describe existing particles as bound states of matter has been solved by calculating bound state matrix elements from a dual fermion-boson Lagrangian. In this formalism, the fermion binding energies are compensated by boson energies, indicating that particles can be generated out of the vacuum. This yields quantitative solutions for various mesons ω (0.78 GeV) - Υ (9.46 GeV) and all leptons e, μ and τ, with uncertainties in the extracted properties of less than 1‰. For transparency, a Web-page with the address htpps://*** has been constructed, where all calculations can be run on line and also the underlying fortran source code can be inspected.

关键词： Quantum Field Theory of Fermion and Boson Fields Hadrons and Leptons Described as Bound States of Relativistic Fermions and Bosons Leading to a Total Energy Equal to Zero

Aerosol deposition technology and its applications in batteries

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Nano Materials Science 2024年第1期6卷 24-37页

作者： Xinyu Wang Ramon Alberto Paredes Camacho Xiaoyu Xu Yumei Wang Yi Qiang hans Kungl Ruediger-AEichel Yunfeng Zhang Li Lu National University of Singapore(Chongqing)Research Institute Chongqing401123PR China National University of Singapore Singapore117576 Fundamental Electrochemistry(IEK-9) Institute of Energy and Climate ResearchForschungszentrum Jülich52425JülichGermany

Aerosol deposition(AD)method is a kind of additive manufacturing technology for fabricating dense films such as metals and ceramics at room *** resolves the challenge of integrating ceramic films onto temperaturesensitive substrates,including metals,glasses,and *** should be emphasized that the AD is a spray coating technology that uses powder without thermal assistance to generate films with high *** to the traditional sputter-based approach,the AD shows several advantages in efficiency,convenience,better interfacial bonding and so ***,it opens some possibilities to the field of batteries,especially all-solidstate batteries(ASSBs)and draws much attention not only for research but also for large scale *** purpose of this work is to provide a critical review on the science and technology of AD as well as its applications in the field of *** process,mechanism and effective parameters of AD,and recent developments in AD applications in the field of batteries will be systematically reviewed so that a trend for AD will be finally provided.

关键词： Aerosol deposition Room temperature impact consolidation Ceramic film All-solid-state battery Spray coating technology

CD4^(+)T cells produce IFN-I to license cDC1s for induction of cytotoxic T-cell activity in human tumors

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Cellular & Molecular Immunology 2024年第4期21卷 374-392页

作者： Xin Lei Daniël C.de Groot Marij.j.P.Welters Tom de Wit Ellen Schrama hans van Eenennaam Saskia j.Santegoets Timo Oosenbrug Annemarthe van der Veen j.ris L.Vos Charlotte L.Zuur Noel F.C.C.de Miranda Heinz j.cobs Sj.erd H.van der Burg j.nnie Borst Yanling Xiao Department of Immunology Leiden University Medical CenterLeidenThe Netherlands Oncode Institute Leiden University Medical CenterLeidenThe Netherlands Department of Tumor Biology and Immunology The Netherlands Cancer InstituteAmsterdamThe Netherlands Department of Medical Oncology Oncode InstituteLeiden University Medical CenterLeidenThe Netherlands IMMIOS B.V. OssThe Netherlands Division of Medical Oncology The Netherlands Cancer InstituteAmsterdamThe Netherlands Department of Otorhinolaryngology Leiden University Medical Center LeidenThe Netherlands Department of Pathology Leiden University Medical CenterLeidenThe Netherlands

CD4^(+)T cells can"help"or"license" conventional type 1 dendritic cells(cDC1s)to induce CD8^(+)cytotoxic T lymphocyte(CTL)anticancer responses,as proven in mouse *** recently identified cDC1s with a transcriptomic imprint of CD4^(+)T-cell help,specifically in T-cell-infiltrated human cancers,and these cells were associated with a good prognosis and response to PD-1-targeting ***,we delineate the mechanism of cDC1 licensing by CD4^(+)T cells in *** CD4^(+)T cells produce IFNβvia the STING pathway,which promotes MHC-I antigen(cross-)presentation by cDC1s and thereby improves their ability to induce CTL anticancer *** cooperation with CD40 ligand(L),IFNβalso optimizes the costimulatory and other functions of cDC1s required for CTL response ***-I-producing CD4^(+)T cells are present in diverse T-cell-infiltrated cancers and likely deliver“help”signals to CTLs locally,according to their transcriptomic profile and colocalization with“helped/licensed”cDCs and tumor-reactive CD8^(+)T *** agreement with this scenario,the presence of IFN-I-producing CD4^(+)T cells in the TME is associated with overall survival and the response to PD-1 checkpoint blockade in cancer patients.

关键词： CD4^(+)T-cell help cDC1 licensing IFN-I signaling CD40 costimulation (cross-)presentation CTL priming Tumor control

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质子磁荷半径:新疑难?

Science Bulletin 2024年第4期69卷 419-421页

作者：林勇辉 hans-Werner Hammer Ulf-G.Meiûner Helmholtz Institut für Strahlen-und Kernphysik and Bethe Center for Theoretical Physics Universität BonnBonn D-53115Germany Technische Universität Darmstadt Department of PhysicsInstitut für KernphysikDarmstadt 64289Germany ExtreMe Matter Institute EMMI and Helmholtz Forschungsakademie Hessen für FAIR GSI Helmholtzzentrum für Schwerionenforschung GmbHDarmstadt 64291Germany Institute for Advanced Simulation and Institut für Kernphysik Forschungszentrum JülichJülich D-52425Germany Tbilisi State University Tbilisi 0186Georgia

The electric radius,rE,and the magnetic radius,rM,of the proton are fundamental quantities of low-energy QCD,as they are a measure of the probe-dependent size of the proton.

关键词： radius quantities fundamental

High-resolution Induan-Olenekian boundary sequence in Chaohu, Anhui Province

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Science China Earth Sciences 2005年第3期48卷 291-297页

作者： hans j. hansen Geological Institute Copenhagen University Oster Voldgade 10 DK-1350 Copenhage Denmark

The West Pingdingshan Section in Chaohu, Southeast China’s Anhui Province is one of the potential GSSP candidates for the Induan-Olenekian boundary. Extensive study has been done on the Induan-Olenekian boundary strata at the section to meet the requirements of defining the GSSP precisely. This paper focuses on the boundary strata at the section to present a review of the main results achieved in recent years. The Induan-Olenekian boundary strata here cover an interval of about four meters at the West Pingdingshan Section, in which the key indices of defining the boundary and the chief transitional processes of some parameters at the boundary are included. The relationship between the boundaries defined by ammonoids and by conodonts is well clarified at the section. The magnetic polarity analysis shows that the boundary interval belongs to a normal polarity zone. Both the carbonate and organic carbon isotopes com- positions experienced a significant conversion in the boundary interval.

关键词： Lower Triassic, Induan-Olenekian boundary, GSSP, candidate, Chaohu of China.