A new genus of fossil Cycads, Yixianophyllum gen. nov., is reported here. The specimens were collected from the southern hill of Jinjiagou village, Toudaohezi Town, Yixian County, western Liaoning Province, China. The...A new genus of fossil Cycads, Yixianophyllum gen. nov., is reported here. The specimens were collected from the southern hill of Jinjiagou village, Toudaohezi Town, Yixian County, western Liaoning Province, China. The fossil plant-beating bed belongs to the lower part, the Zhuanchengzi bed, of the Upper Jurassic Yixian Formation （Yixianian）. The new genus in leaf shape, venation and epidermal structure shows a transitional form between Mesozoic Cycads （Ctenis, Nilssonia） and modem Cycads （Stangeria and Encephalartos）. Since the features of these specimens differ from any known genera of Cycads, a new generic name Yixianophyllum is proposed for these leaves. Typical species, Yixianophyllum jinjiagouense gen. et sp. nov. is described here. A supposed evolutionary tendency of Cycadean leaf-forms with Taeniopteris-type is discussed.展开更多
Salamanders have evolved functions of attaching to a variety of surfaces under wet conditions,but racial diversity may cause a difference in attachment behaviors and epidermal characteristics.The sticking and climbing...Salamanders have evolved functions of attaching to a variety of surfaces under wet conditions,but racial diversity may cause a difference in attachment behaviors and epidermal characteristics.The sticking and climbing abilities of the Chinese Fire Belly Newt(CFBN),Chinese Warts Triton(CWT),Spotless Stout Newt(SSN),and Chinese Giant Salamander(CGS)on various surfaces were investigated and compared in terms of epidermal morphology,body size,and wettability.The results indicate that the spotless stout newt has an excellent ability for wet attachment,compared to other salamanders under a certain contact case,resulting from its lower mass/body surface area and more visible epidermal structures.Supplementation with moderate water is beneficial for salamander attachment,and the surface roughness in the flood case also promotes the wet attachment.The CFBN has the most hydrophilic epidermis among the samples,where the water droplet quickly spreads over,presenting a completely wetting case.This study offers a comprehensive understanding of the wet attachments and the epidermal characteristics of salamanders,which is meaningful for the application of bioinspired adhesives.展开更多
文摘A new genus of fossil Cycads, Yixianophyllum gen. nov., is reported here. The specimens were collected from the southern hill of Jinjiagou village, Toudaohezi Town, Yixian County, western Liaoning Province, China. The fossil plant-beating bed belongs to the lower part, the Zhuanchengzi bed, of the Upper Jurassic Yixian Formation （Yixianian）. The new genus in leaf shape, venation and epidermal structure shows a transitional form between Mesozoic Cycads （Ctenis, Nilssonia） and modem Cycads （Stangeria and Encephalartos）. Since the features of these specimens differ from any known genera of Cycads, a new generic name Yixianophyllum is proposed for these leaves. Typical species, Yixianophyllum jinjiagouense gen. et sp. nov. is described here. A supposed evolutionary tendency of Cycadean leaf-forms with Taeniopteris-type is discussed.
基金National Natural Science Foundation of China,51675268,Xiaolei WangNatural Science Research Fund of Higher Education of Anhui Province,KJ2020A0230,Meng Li+3 种基金open project of key laboratory of green fabrication and surface technology of advanced metal materials,GFST2021KF05,Meng Liopen project of Anhui Province Key Laboratory of special and heavy load robot,TZJQR004-2021,Meng LiNatural Science Foundation of Anhui Province of China,2108085QE228,Meng LiNatural Science Foundation of Anhui Province of China,2108085ME174,Liping Shi。
文摘Salamanders have evolved functions of attaching to a variety of surfaces under wet conditions,but racial diversity may cause a difference in attachment behaviors and epidermal characteristics.The sticking and climbing abilities of the Chinese Fire Belly Newt(CFBN),Chinese Warts Triton(CWT),Spotless Stout Newt(SSN),and Chinese Giant Salamander(CGS)on various surfaces were investigated and compared in terms of epidermal morphology,body size,and wettability.The results indicate that the spotless stout newt has an excellent ability for wet attachment,compared to other salamanders under a certain contact case,resulting from its lower mass/body surface area and more visible epidermal structures.Supplementation with moderate water is beneficial for salamander attachment,and the surface roughness in the flood case also promotes the wet attachment.The CFBN has the most hydrophilic epidermis among the samples,where the water droplet quickly spreads over,presenting a completely wetting case.This study offers a comprehensive understanding of the wet attachments and the epidermal characteristics of salamanders,which is meaningful for the application of bioinspired adhesives.
