Anatomical data regarding the climbing modes and cambial variants of the stem transverse section in the Menispermaceae in Taiwan are lacking. Here, we examined the climbing modes and anomalous structure of climber ste...Anatomical data regarding the climbing modes and cambial variants of the stem transverse section in the Menispermaceae in Taiwan are lacking. Here, we examined the climbing modes and anomalous structure of climber stems in this family. Reviewing the previous reports of cambial variants in angiosperm liana families, a list of angiosperm liana families processing specified types of cambial variants and the terms based on description for the transverse section of a stem were provided. The results show that Cocculus laurifolius DC. is a shrub, Stephania cephalantha Hayata and Stephania longa Lour. are vines, and the remaining 13 species are lianas. In all species, the climbing mode was twining and dextrorse stems. The anomalous structure of the stem comprised successive cambia in Cocculus laurifolius, a combination of xylem in plates and dissected xylem in Cocculus orbiculatus (L.) DC., and xylem in plates in the remaining 14 species. In the genus Cyclea, parenchyma proliferation from the secondary xylem resulted in the development of 1 - 3 linear lobes in each collateral vascular bundle. The vessel diameter of C. laurifolius is <50 μm which is the smallest size due to shrub in its life stage. C. orbiculatus had the longest collateral vascular bundles, longest rays and widest rays. Cyclea ochiaiana (Yamam.) S. F. Huang & T. C. Huang had the widest collateral vascular bundles. Sinomenium acutum (Thunb.) Rehder & E. H. Wilson had the highest vessel density. Tinospora crispa (L.) Hook. F. et Thoms develops blunt tubercles on the epidermis and Stephania tetrandra S. Moore bears conspicuous phellem layer. Those findings, such as the climbing mode, the features of parenchyma proliferation, the features of collateral vascular bundles (number, width, length), dimorphic vessels, and size and density of vessels, highlight new anatomical characteristics for species identification in the Menispermaceae in Taiwan.展开更多
The dominant hydride precipitates have been well demonstrated to follow two types of orientation relationships(ORs)with Ti matrix:OR1 with{0001}//{001},<1210>//<110>and OR2 with{0001}//{111},<1210>//...The dominant hydride precipitates have been well demonstrated to follow two types of orientation relationships(ORs)with Ti matrix:OR1 with{0001}//{001},<1210>//<110>and OR2 with{0001}//{111},<1210>//<110>.Within the grains with special orientations,the complicated interactions of different hydride variants inside Ti-hydride diffusion layer are characterized in this work.For OR1 hydride layer,the orientations of{1010}plane parallel to the sample surface and a-axis parallel to the normal direction prefer multiple OR1 variants.The orientations favorable for OR2 hydride layer are:{1013}plane parallel to sample surface corresponding to the layer with one OR2 variant dominated and c-axis parallel to the surface normal with multiple OR2 variant layer preferred.Furthermore,{1012}extension twins and{1122}contraction twins are activated to accommodate the OR2 hydride-induced surface expansion and local misfit strain.The stimulation of these two twins is also orientation-dependent:{1012}and{1122}twins are observed in the grains with c-axis parallel to and deviated from the surface normal,respectively.The further variant selection for each twin mode is performed through shear accommodation of hydride-twin pairs.展开更多
文摘Anatomical data regarding the climbing modes and cambial variants of the stem transverse section in the Menispermaceae in Taiwan are lacking. Here, we examined the climbing modes and anomalous structure of climber stems in this family. Reviewing the previous reports of cambial variants in angiosperm liana families, a list of angiosperm liana families processing specified types of cambial variants and the terms based on description for the transverse section of a stem were provided. The results show that Cocculus laurifolius DC. is a shrub, Stephania cephalantha Hayata and Stephania longa Lour. are vines, and the remaining 13 species are lianas. In all species, the climbing mode was twining and dextrorse stems. The anomalous structure of the stem comprised successive cambia in Cocculus laurifolius, a combination of xylem in plates and dissected xylem in Cocculus orbiculatus (L.) DC., and xylem in plates in the remaining 14 species. In the genus Cyclea, parenchyma proliferation from the secondary xylem resulted in the development of 1 - 3 linear lobes in each collateral vascular bundle. The vessel diameter of C. laurifolius is <50 μm which is the smallest size due to shrub in its life stage. C. orbiculatus had the longest collateral vascular bundles, longest rays and widest rays. Cyclea ochiaiana (Yamam.) S. F. Huang & T. C. Huang had the widest collateral vascular bundles. Sinomenium acutum (Thunb.) Rehder & E. H. Wilson had the highest vessel density. Tinospora crispa (L.) Hook. F. et Thoms develops blunt tubercles on the epidermis and Stephania tetrandra S. Moore bears conspicuous phellem layer. Those findings, such as the climbing mode, the features of parenchyma proliferation, the features of collateral vascular bundles (number, width, length), dimorphic vessels, and size and density of vessels, highlight new anatomical characteristics for species identification in the Menispermaceae in Taiwan.
基金the China Scholarship Council for the financial support。
文摘The dominant hydride precipitates have been well demonstrated to follow two types of orientation relationships(ORs)with Ti matrix:OR1 with{0001}//{001},<1210>//<110>and OR2 with{0001}//{111},<1210>//<110>.Within the grains with special orientations,the complicated interactions of different hydride variants inside Ti-hydride diffusion layer are characterized in this work.For OR1 hydride layer,the orientations of{1010}plane parallel to the sample surface and a-axis parallel to the normal direction prefer multiple OR1 variants.The orientations favorable for OR2 hydride layer are:{1013}plane parallel to sample surface corresponding to the layer with one OR2 variant dominated and c-axis parallel to the surface normal with multiple OR2 variant layer preferred.Furthermore,{1012}extension twins and{1122}contraction twins are activated to accommodate the OR2 hydride-induced surface expansion and local misfit strain.The stimulation of these two twins is also orientation-dependent:{1012}and{1122}twins are observed in the grains with c-axis parallel to and deviated from the surface normal,respectively.The further variant selection for each twin mode is performed through shear accommodation of hydride-twin pairs.
