Plants produce a rich diversity of biological forms,and the diversity of leaves is especially notable.Mechanisms of leaf morphogenesis have been studied in the past two decades,with a growing focus on the interactive ...Plants produce a rich diversity of biological forms,and the diversity of leaves is especially notable.Mechanisms of leaf morphogenesis have been studied in the past two decades,with a growing focus on the interactive roles of mechanics in recent years.Growth of plant organs involves feedback by mechanical stress:growth induces stress,and stress affects growth and morphogenesis.Although much attention has been given to potential stress-sensing mechanisms and cellular responses,the mechanical principles guiding morphogenesis have not been well understood.Here we synthesize the overarching roles of mechanics and mechanical stress in multilevel and multiple stages of leaf morphogenesis,encompassing leaf primordium initiation,phyllotaxis and venation patterning,and the establishment of complex mature leaf shapes.Moreover,the roles of mechanics at multiscale levels,from subcellular cytoskeletal molecules to single cells to tissues at the organ scale,are articulated.By highlighting the role of mechanical buckling in the formation of three-dimensional leaf shapes,this review integrates the perspectives of mechanics and biology to provide broader insights into the mechanobiology of leaf morphogenesis.展开更多
Using a generalized quasi-continuum method,we characterize the post-buckling morphologies and energetics of thick multi-walled carbon nanotubes(MWCNTs)under uniaxial compression.Our simulations identify for the first ...Using a generalized quasi-continuum method,we characterize the post-buckling morphologies and energetics of thick multi-walled carbon nanotubes(MWCNTs)under uniaxial compression.Our simulations identify for the first time evolving post-buckling morphologies,ranging from asymmetric periodic rippling to a helical diamond pattern.We attribute the evolving morphologies to the coordinated buckling of the constituent shells.The post-buckling morphologies result in significantly reduced effective moduli that are strongly dependent on the aspect ratio.Our simulation results provide fundamental principles to guide the future design of high-performance,MWCNT-based nanodevices.展开更多
基金support from Nanyang Technological University(grant no.M4082428)K.J.H.and C.H.acknowledge support from Nanyang Technological University under its Accelerating Creativity and Excellence(ACE)grant(grant no.NTU-ACE2020-07)+2 种基金supported by the Center for Engineering Mechano Biology,an National Science Foundation(NSF)Science and Technology Center,under grant agreement No.CMMI:15-48571supported by the U.S.Department of Energy(grant no.DE-FG2-84ER13179)support from the Ministry of Education-Singapore,under its Academic Research Fund Tier 1(RT11/20 and RG32/20).
文摘Plants produce a rich diversity of biological forms,and the diversity of leaves is especially notable.Mechanisms of leaf morphogenesis have been studied in the past two decades,with a growing focus on the interactive roles of mechanics in recent years.Growth of plant organs involves feedback by mechanical stress:growth induces stress,and stress affects growth and morphogenesis.Although much attention has been given to potential stress-sensing mechanisms and cellular responses,the mechanical principles guiding morphogenesis have not been well understood.Here we synthesize the overarching roles of mechanics and mechanical stress in multilevel and multiple stages of leaf morphogenesis,encompassing leaf primordium initiation,phyllotaxis and venation patterning,and the establishment of complex mature leaf shapes.Moreover,the roles of mechanics at multiscale levels,from subcellular cytoskeletal molecules to single cells to tissues at the organ scale,are articulated.By highlighting the role of mechanical buckling in the formation of three-dimensional leaf shapes,this review integrates the perspectives of mechanics and biology to provide broader insights into the mechanobiology of leaf morphogenesis.
基金We gratefully acknowledge support from the National Science Foundation(NSF)grants under Awards Nos.0826841 and 0600642(Clark V.Cooper,program manager)and K.J.H.acknowledges NSF financial support under Grant Nos.CMMI 09-52565 and CMMI 09-06361.
文摘Using a generalized quasi-continuum method,we characterize the post-buckling morphologies and energetics of thick multi-walled carbon nanotubes(MWCNTs)under uniaxial compression.Our simulations identify for the first time evolving post-buckling morphologies,ranging from asymmetric periodic rippling to a helical diamond pattern.We attribute the evolving morphologies to the coordinated buckling of the constituent shells.The post-buckling morphologies result in significantly reduced effective moduli that are strongly dependent on the aspect ratio.Our simulation results provide fundamental principles to guide the future design of high-performance,MWCNT-based nanodevices.
