The wet grip of tire has always been the focus because it is related to the personal safety of passengers directly.Many methods were employed to improve the wet grip of tire.Researchers paid more attention on bionics ...The wet grip of tire has always been the focus because it is related to the personal safety of passengers directly.Many methods were employed to improve the wet grip of tire.Researchers paid more attention on bionics method recent years.In nature,tree frogs have high adhesion ability in wet environment,which is mainly due to their footpads having fine polygon grooves(mainly hexagon grooves).To improve the performance of wet grip of tire,from the perspective of bionics,inspired by the footpad of tree frog,the bionic hexagon tread pattern was designed.The friction test was carried out to compare with the common tread patterns such as serrated,striped and square patterns.The results showed that the bionic hexagon tread pattern generally had high friction coefficient and directional stability of friction.The main reason was that the hexagon tread block was less affected by the friction-induced torque and the groove of bionic hexagon tread pattern had better drainage characteristic.The bionic hexagon tread pattern provides new idea and method for the design of tires with high wet grip.展开更多
<span style="font-family:Verdana;">This study examined the relationship between tree frog</span> (<i><i><span style="font-family:Verdana;">Hyla</span></i>&...<span style="font-family:Verdana;">This study examined the relationship between tree frog</span> (<i><i><span style="font-family:Verdana;">Hyla</span></i><span> <i><span style="font-family:Verdana;">savignyi</span></i><span style="font-family:Verdana;"></span></span></i><span style="font-family:Verdana;">)</span><span style="font-family:Verdana;"> coloring and its different seasonal habitats at the southern border of its distribution. The results show that tree frog color is affected by the dominant colors in its habitat, which vary seasonally, especially between winter and summer. Tree frog colors were various shades of green, white, brown, and black. No genetic marker was found to characterize the color. The ability of a small frog to infer its own time with the help of color changes occurring in the habitat on the southern border of its distribution, which are relatively broad, gives this species an advantage.</span>展开更多
The tree frog is a prominent amphibian among terrestrial vertebrates known for its ability to adhere to various surfaces through the capillary forces of water in the microchannels between micropillars on its disc-shap...The tree frog is a prominent amphibian among terrestrial vertebrates known for its ability to adhere to various surfaces through the capillary forces of water in the microchannels between micropillars on its disc-shaped toe pads,a phenomenon known as wet adhesion.However,the secretion pattern of mucus on the attachment surface of living tree frog toe pads and the distribution of active mucus pores(AMPs)have not yet been fully elucidated.In this study,we utilized synchrotron X-ray micro-computed tomography and interference reflection microscopy to obtain the spatial distribution of the entire population of ventral mucus glands on the toe pads of living tree frogs and the real-time mucus secretion patterns from the ventral mucus pores on the contact surface under different environmental conditions.We observed that the number and secretion frequency of AMPs on the toe pad are regulated according to environmental conditions.Such dynamic mucus secretion on the tree frog’s toe pad could contribute to the understanding of capillary force regulation for wet adhesion and the development of adhesive surfaces by mimicking the mucus-secreting toe pad.展开更多
Since tadpoles change their behavior when facing adverse environmental conditions, observing tadpoles in a tank can help detect problems in their ma intena nce. Detecting such a bnormal behavior early, an amphibian br...Since tadpoles change their behavior when facing adverse environmental conditions, observing tadpoles in a tank can help detect problems in their ma intena nce. Detecting such a bnormal behavior early, an amphibian breeder can react quickly, by changing the conditions. If quick and appropriate, such a reaction can save unnecessary deaths. The paper presents an experimental study on the behavior of tadpoles of Polypedates megacephalus in various adverse environmental conditions. In addition to a control 25-liter tank, 5-liter tanks with 10 tadpoles each were studied, each having various improper conditions. Observations included the degree of tank exploration by the tadpoles, their mortality, anomalies in swimming behavior, and eating behavior.展开更多
Genus Rhacophorus Kuhl and Van Hasselt, 1 822 is one of the most diverse genera of the family Rhacophoridae, and its taxonomy of genus Rhacophorus faces major challenges because of rapidly described new species and co...Genus Rhacophorus Kuhl and Van Hasselt, 1 822 is one of the most diverse genera of the family Rhacophoridae, and its taxonomy of genus Rhacophorus faces major challenges because of rapidly described new species and complex interspecies relations. In this study, we investigate the generic taxonomy within the genus Rhacophorus based on 1 972 bp of mitochondrial genes(12S rRNA, tRNA-val and 16S rRNA), containing 102 sequences from 58 species. The results reveal three well-supported and highly diverged matrilines that correspond with morphological characteristics and geographic distribution. Accordingly, we consider these three lineages as distinct genera: Rhacophorus sensu stricto, resurrected genus Leptomantis Peters, 1867, and the genus Zhangixalus gen. nov.展开更多
基金supported by the National Key R&D Plan(2016YFD0701102)the Graduate Innovation Fund of Jilin University(101832020CX166)+3 种基金the Science-Technology Development Plan Project of Jilin Province(20200403038SF,20200501013GX,20200403006SF)the"13th Five-Year Plan"Scientific Research Foundation of the Education Department of Jilin Province(JJKH20201000KJ,JJKH20211120KJ)the Talent Development Foundation of Jilin Province(2020015)the Fundamental Research Foundation for the Central Universities.
文摘The wet grip of tire has always been the focus because it is related to the personal safety of passengers directly.Many methods were employed to improve the wet grip of tire.Researchers paid more attention on bionics method recent years.In nature,tree frogs have high adhesion ability in wet environment,which is mainly due to their footpads having fine polygon grooves(mainly hexagon grooves).To improve the performance of wet grip of tire,from the perspective of bionics,inspired by the footpad of tree frog,the bionic hexagon tread pattern was designed.The friction test was carried out to compare with the common tread patterns such as serrated,striped and square patterns.The results showed that the bionic hexagon tread pattern generally had high friction coefficient and directional stability of friction.The main reason was that the hexagon tread block was less affected by the friction-induced torque and the groove of bionic hexagon tread pattern had better drainage characteristic.The bionic hexagon tread pattern provides new idea and method for the design of tires with high wet grip.
文摘<span style="font-family:Verdana;">This study examined the relationship between tree frog</span> (<i><i><span style="font-family:Verdana;">Hyla</span></i><span> <i><span style="font-family:Verdana;">savignyi</span></i><span style="font-family:Verdana;"></span></span></i><span style="font-family:Verdana;">)</span><span style="font-family:Verdana;"> coloring and its different seasonal habitats at the southern border of its distribution. The results show that tree frog color is affected by the dominant colors in its habitat, which vary seasonally, especially between winter and summer. Tree frog colors were various shades of green, white, brown, and black. No genetic marker was found to characterize the color. The ability of a small frog to infer its own time with the help of color changes occurring in the habitat on the southern border of its distribution, which are relatively broad, gives this species an advantage.</span>
基金supported by a National Research Foundation of Korea grant funded by the Korean government(MSIT)(Grant Nos.2022R1A2C1007366 and 2021R1A2C1008787).
文摘The tree frog is a prominent amphibian among terrestrial vertebrates known for its ability to adhere to various surfaces through the capillary forces of water in the microchannels between micropillars on its disc-shaped toe pads,a phenomenon known as wet adhesion.However,the secretion pattern of mucus on the attachment surface of living tree frog toe pads and the distribution of active mucus pores(AMPs)have not yet been fully elucidated.In this study,we utilized synchrotron X-ray micro-computed tomography and interference reflection microscopy to obtain the spatial distribution of the entire population of ventral mucus glands on the toe pads of living tree frogs and the real-time mucus secretion patterns from the ventral mucus pores on the contact surface under different environmental conditions.We observed that the number and secretion frequency of AMPs on the toe pad are regulated according to environmental conditions.Such dynamic mucus secretion on the tree frog’s toe pad could contribute to the understanding of capillary force regulation for wet adhesion and the development of adhesive surfaces by mimicking the mucus-secreting toe pad.
文摘Since tadpoles change their behavior when facing adverse environmental conditions, observing tadpoles in a tank can help detect problems in their ma intena nce. Detecting such a bnormal behavior early, an amphibian breeder can react quickly, by changing the conditions. If quick and appropriate, such a reaction can save unnecessary deaths. The paper presents an experimental study on the behavior of tadpoles of Polypedates megacephalus in various adverse environmental conditions. In addition to a control 25-liter tank, 5-liter tanks with 10 tadpoles each were studied, each having various improper conditions. Observations included the degree of tank exploration by the tadpoles, their mortality, anomalies in swimming behavior, and eating behavior.
基金supported by National Key R&D Program of China (2016YFC1200705)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB31000000)+4 种基金the National Natural Science Foundation of China (31722049, 31772434)Key Research Program of Frontier Sciences, CAS (QYZDBSSW-SMC058)the Youth Innovation Promotion Association of CASSoutheast Asia Biodiversity Research Institute (Y4ZK111B01)the CAS "Light of West China" Program (2018XBZG_JCTD_001)
文摘Genus Rhacophorus Kuhl and Van Hasselt, 1 822 is one of the most diverse genera of the family Rhacophoridae, and its taxonomy of genus Rhacophorus faces major challenges because of rapidly described new species and complex interspecies relations. In this study, we investigate the generic taxonomy within the genus Rhacophorus based on 1 972 bp of mitochondrial genes(12S rRNA, tRNA-val and 16S rRNA), containing 102 sequences from 58 species. The results reveal three well-supported and highly diverged matrilines that correspond with morphological characteristics and geographic distribution. Accordingly, we consider these three lineages as distinct genera: Rhacophorus sensu stricto, resurrected genus Leptomantis Peters, 1867, and the genus Zhangixalus gen. nov.
