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Enhanced and asymmetric signatures of hybridizat.on at climatic margins: Evidence from closely related dioecious fig species

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Plant Diversity 2024年第2期46卷 181-193页

作者： Jian-feng Huang Clive t.Darwell Yan-Qiong Peng CAS Key Laboratory of t.opical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303China Nat.onal Center for Genetic Engineering and Biotechnology(BIotEC) 113 Thailand Science ParkPhahonyothin RoadKhlong NuengKhlong LuangPathum Thani 12120Thailand

Hybridizat.on plays a significant role in biological evolut.on. However, it is not clear whether ecological contingency differentially influences likelihood of hybridizat.on, particularly at ecological margins where parental species may exhibit reduced fitnesses. Moreover, it is unknown whether future ecosystem change will increase the prevalence of hybridizat.on. Ficus heterostyla and F. squamosa are closely related species co-distributed from southern thailand to southwest China where hybridizat.on, yielding viable seeds, has been documented. As a robust test.of ecological factors driving hybridizat.on, we investigated spatial hybridizat.on signatures based on nuclear microsatellites from extensive populat.on sampling across a widespread contact range. Both species showed high populat.on differentiat.on and st.ong patterns of isolat.on by distance. Admixture estimates exposed asymmetric interspecific gene *** of hybridizat.on increase significantly towards higher latitude zones, peaking at the northern climatic margins. Geographic variat.on in reproductive phenology combined with ecologically challenging marginal habitats may promote this phenomenon. our work is a first systematic evaluat.on of such patterns in a comprehensive, latitudinally-based clinal context, and indicates that tendency to hybridize appears st.ongly influenced by environmental condit.ons. Moreover, that future climate change scenarios will likely alter and possibly augment cases of hybridizat.on at ecosystem scales.

关键词： Hybridizat.on Heterospecific visitat.on Fig Pollinator wasp Asymmetric gene flow

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Multi-layer percept.on-based data-driven multiscale modelling of granular materials with a novel Frobenius norm-based internal variable

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2198-2218页

作者： Mengqi Wang Y.t.feng Shaoheng Guan tongming Qu Zienkiewicz Centre for Computat.onal Engineering Faculty of Science and EngineeringSwansea UniversitySwanseaWalesSA18EPUK Institute of theoretical and Computat.onal Physics Graz University of TechnologyGraz8010Austria Department.of Civil and Environmental Engineering Hong Kong University of Science and TechnologyClearwater BayKowloonHong KongChina

one objective of developing machine learning(ML)-based material models is to integrate them with well-established numerical met.ods to solve boundary value problems(BVPs).In the family of ML models,recurrent neural net.orks(RNNs)have been extensively applied to capture history-dependent constitutive responses of granular materials,but these multiple-step-based neural net.orks are neither sufficiently efficient nor aligned with the standard finite element met.od(FEM).Single-step-based neural net.orks like the multi-layer percept.on(MLP)are an alternative to bypass the above issues but have to int.oduce some internal variables to encode complex loading *** this work,one novel Frobenius norm-based internal variable,together with the Fourier layer and residual architectureenhanced MLP model,is crafted to replicate the history-dependent constitutive features of representative volume element(RVE)for granular *** obtained ML models are then seamlessly embedded into the FEM to solve the BVP of a biaxial compression case and a rigid strip footing *** obtained solut.ons are comparable to results from the FEM-DEM multiscale modelling but achieve significantly improved *** results demonstrate the applicability of the proposed internal variable in enabling MLP to capture highly nonlinear constitutive responses of granular materials.

关键词： Granular materials History-dependence Multi-layer percept.on(MLP) Discrete element met.od FEM-DEM Machine learning

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Increasing polymer scission rate by tying an overhand knot

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Science China Chemistry 2024年第11期67卷 3498-3499页

作者： Yuheng Hu Jennifer t.ou Jim Y.Huang Yuanning feng Department.of Chemistry and Biochemistry The University of Oklahoma

Similar to the phenomenon of knotted ropes in life, knotted climbing ropes will reduce their strength due to knots. Alt.ough computer simulat.ons [1], theoretical speculat.on[2,3], and intuit.on [3] suggest that similar processes may occur at the nanoscale, this hypothesis has not been experimentally proven before. With the increasing maturity of molecular recognit.on and self-assembly, a research communicat.on by Leigh et al. [4] published in Nature Chemistry int.oduced a molecular overhand knot into a polymer to study its effect.on the scission rate of the polymer chain under tension.

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A particle-resolved heat-particle-fluid coupling model by DEM-IMB-LBM

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2267-2281页

作者： Ming Xia Jinlong Fu Y.t.feng fengqiang Gong Jin Yu Hunan Key Laboratory of Geomechanics and Engineering Safety Xiangtan UniversityXiangtan411105China Zienkiewicz Institute for Modelling Data and AISwansea UniversitySwanseaSA18EPUK School of Civil Engineering Southeast UniversityNanjing211189China Fujian Research Center for tunneling and Urban Underground Space Engineering Huaqiao UniversityXiamen361021China

Multifield coupling is frequently encountered and also an active area of research in geotechnical *** this work,a particle-resolved direct numerical simulat.on(PR-DNS)technique is extended to simulate particle-fluid interact.on problems involving heat transfer at the grain *** this extended technique,an immersed moving boundary(IMB)scheme is used to couple the discrete element met.od(DEM)and lattice Boltzmann met.od(LBM),while a recently proposed Dirichlet-type thermal boundary condit.on is also adapted to account for heat transfer between fluid phase and solid *** resulting DEM-IBM-LBM model is robust to simulate moving curved boundaries with constant temperature in thermal *** facilitate the understanding and implementat.on of this coupled model for non-isothermal problems,a complete list is given for the conversion of relevant physical variables to lattice ***,benchmark tests,including a single-particle sedimentat.on and a t.o-particle drafting-kissing-tumbling(DKt)simulat.on with heat transfer,are carried out to validate the accuracy of our coupled *** further investigate the role of heat transfer in particle-laden flows,t.o multiple-particle problems with heat transfer are *** examples demonstrate that the proposed coupling model is a promising high-resolut.on approach for simulating the heat-particle-fluid coupling at the grain level.

关键词： Particle-fluid interact.on Heat transfer Discrete element met.od(DEM) Lattice Boltzmann met.od(LBM) Dirichlet-type thermal boundary Direct numerical simulat.on

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An MPI parallel DEM-IMB-LBM framework for simulating fluid-solid interact.on problems

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2219-2231页

作者： Ming Xia Liuhong Deng fengqiang Gong tongming Qu Y.t.feng Jin Yu Hunan Key Laboratory of Geomechanics and Engineering Safety Xiangtan UniversityXiangtan411105China School of Civil Engineering Southeast UniversityNanjing211189China Department.of Civil and Environmental Engineering Hong Kong University of Science and TechnologyHong KongChina Zienkiewicz Centre for Computat.onal Engineering Swansea UniversitySwanseaSA18ENUK Fujian Research Center for tunneling and Urban Underground Space Engineering Huaqiao UniversityXiamen361021China

the high-resolut.on DEM-IMB-LBM model can accurately describe pore-scale fluid-solid interact.ons,but its potential for use in geotechnical engineering analysis has not been fully unleashed due to its prohibitive computat.onal *** overcome this limitat.on,a message passing interface(MPI)parallel DEM-IMB-LBM framework is proposed aimed at enhancing computat.on *** framework utilises a static domain decomposit.on scheme,with the entire computat.on domain being decomposed into multiple subdomains according to predefined processors.A detailed parallel strategy is employed for both contact detect.on and hydrodynamic force *** particular,a particle ID re-numbering scheme is proposed to handle particle transit.ons across sub-domain *** benchmarks are conducted to validate the accuracy and overall performance of the proposed ***,the framework is applied to simulate scenarios involving multi-particle sedimentat.on and submarine *** numerical examples effectively demonstrate the robustness and applicability of the MPI parallel DEM-IMB-LBM framework.

关键词： Discrete element met.od(DEM) Lattice Boltzmann met.od(LBM) Immersed moving boundary(IMB) Multi-cores parallelizat.on Message passing interface(MPI) CPU Submarine landslides

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Rat.onal Solut.ons of First.order Algebraic ordinary Differential Equat.ons

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Journal of Systems Science & Complexity 2024年第2期37卷 567-580页

作者： feng Shuang SHEN Liyong School of Physical and Mathematical Sciences Nanjing Tech UniversityNanjing 211816China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

Let f(t,y,y')=∑ _(i=0)^(n )a_(i)(t,y)y'^(i)=0 be an irreducible first.order ordinary differential equat.on with polynomial *** in 1998 proved that there exists a constant C such that every rat.onal solut.on of f(t,y,y')=0 is of degree not greater than *** show that this degree bound C depends not.only on the degrees of f in t,y,y' but also on the coefficients of f viewed as the polynomial in t,y,y'.In this paper,the aut.ors show that if f satisfies deg(f,y)or n max i=0{deg(a_(i),y)−2(n−i)}>0,then the degree bound C only depends on the degrees of f in t,y,y',and furthermore we present an explicit expression for C in terms of the degrees of f in t,y,y'.

关键词： Degree bound first.order AoDE height rat.onal solut.on

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Editorial for Multiscale&Multifield Coupling in Geomechanics

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 1919-1921页

作者： Min Wang Pengzhi Pan Andrew H.C.Chan Y.t.feng t-3 Fluid Dynamics and Solid Mechanics Theoretical DivisionLos Alamos National LaboratoryNew MexicoUSA Institute of Rock and Soil Mechanics Chinese Academy of SciencesWuhanChina School of Engineering University of TasmaniaTasmaniaAustralia College of Engineering Swansea UniversityWalesUK

We are delighted to serve as guest editors for this special issue in the Journal of Rock Mechanics and Geotechnical *** purpose of this special issue is dedicated to gathering the latest research work on Multiscale&Multifield Coupling in Geomechanics,where we delve into the intricate interplay of various fields and scales that govern the behavior of *** total,30 manuscripts from USA,China,UK,Germany,Canada,India and United Arab Emirates are selected to be included in this issue.

关键词： materials. gathering mechanics

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Enhanced High-temperature Energy Storage Performance of All-organic Composite Dielectric via Constructing Fiber-Re in forced Structure

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Energy & Environmental Materials 2024年第2期7卷 299-307页

作者： Mengjia feng Yu feng Changhai Zhang tiandong Zhang Xu tong Qiang Gao Qingguo Chen Qingguo Chi Key Laboratory of Engineering Dielectrics and Its Applicat.on Ministry of EducationHarbin University of Science and TechnologyHarbin 150080China School of Electrical and Elect.onic Engineering Harbin University of Science and TechnologyHarbin 150080China

optimizing the high-temperature energy storage characteristics of energy storage dielectrics is of great significance for the development.of pulsed power devices and power cont.ol *** a polymer with a higher glass transit.on temperature(t_(g))as the matrix is one of the effective ways to increase the upper limit.of the polymer operating ***,current high-t_(g)polymers have limitat.ons,and it is difficult to meet the demand for high-temperature energy storage dielectrics with only one *** example,polyetherimide has high-energy storage efficiency,but low breakdown strength at high *** has high corona resistance,but low high-temperature energy storage *** this work,combining the advantages of t.o polymer,a novel high-t_(g)polymer fiber-reinforced microstructure is *** is designed as extremely fine fibers distributed in the composite dielectric,which will facilitate the reduct.on of high-temperature conductivity loss for *** the same time,due to the high-temperature resistance and corona resistance of polyimide,the high-temperature breakdown strength of the composite dielectric is *** the polyimide content with the best high-temperature energy storage characteristics is determined,molecular semiconductors(ItIC)are blended into the polyimide fibers to further improve the high-temperature ***,excellent high-temperature energy storage properties are *** 0.25 vol%ItIC-polyimide/polyetherimide composite exhibits high-energy density and high discharge efficiency at 150℃(2.9 J cm^(-3),90%)and 180℃(2.16 J cm^(-3),90%).this work provides a scalable design idea for high-performance all-organic high-temperature energy storage dielectrics.

关键词： all-organic energy storage density high-temperature high-temperature breakdown strength

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Attractor for the Extensible Beam Equat.on with Nonlocal Weak Damping on time–Dependent Space

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1115-1126页

作者： Chun Xiang ZHAo feng Juan MENG Institute of Applied System Analysis Jiangsu UniversityZhenjiang 212013P.R.China School of Mathematics and Physics Jiangsu University of TechnologyChangzhou 213001P.R.China

In this article,we consider the long-time behavior of extensible beams with nonlocal weak damping:ε(t)u_(tt)+Δ^(2)u-m(‖▽u‖^(2))Δu+‖u_(t)‖^(p_(u_(t)))+f(u)=h,whereε(t)is a decreasing funct.on vanishing at *** the theory of process on time-dependent spaces,we investigate the existence of the time-dependent attractor by using the Condit.on(C_(t))met.od and more detailed *** results obtained essentially improve and complete some previous works.

关键词： time-dependent attractor extensible beams equat.on nonlocal weak damping

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Resilient sliding mode cont.ol for 2D CPSs under denial-of-service attacks

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Science China(Informat.on Sciences) 2024年第6期67卷 262-278页

作者： Lingling LI Rongni YANG Zhiguang feng Ligang WU College of Intelligent Systems Science and Engineering Harbin Engineering University School of Cont.ol Science and Engineering Shandong University School of Ast.onautics Harbin Institute of Technology

this study addresses the resilient sliding mode cont.ol(SMC) problem for t.o-dimensional cyber-physical systems(2D CPSs) characterized by the Roesser model under denial-of-service attack(DoSA), which can interfere with signal transmission over the communicat.on net.ork. First, the DoS-A model is established by int.oducing constraints on the Do S frequency and durat.on. then, based on active or silent attack situat.ons, the considered system is described as a switched mode. Furthermore, together with Lyapunov theory, the average dwell time technique is employed to deduce sufficient criteria that assure the existence of the desired sliding mode cont.oller. Finally, verificat.on examples are provided to show the validity of the established SMC scheme.

关键词： t.o-dimensional systems cyber-physical systems denial-of-service attack resilient sliding mode cont.ol

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