<div style="text-align:justify;"> Due to the poor anti-clogging performance of the common drip irrigation emitters, this paper designed a new bionic flow channel in the emitter based on the shape of sh...<div style="text-align:justify;"> Due to the poor anti-clogging performance of the common drip irrigation emitters, this paper designed a new bionic flow channel in the emitter based on the shape of shark dorsal fin. After preliminary structural design, the computational fluid dynamics (CFD) simulation showed that the bionic emitter exhibited superior anti-clogging performance and reasonable hydraulic performance. The passage rate of particles of the bionic emitter in simulation reached 96.3% which was 37.6% higher than 70% of traditional emitter, and the discharge exponent reached 0.4995 which was close to traditional emitter. Physical experiments were consistent with the CFD results, which confirmed the correctness of simulation. After a short cycle anti-clogging performance experiment, the bionic emitter still maintained 96.09% of the initial flow rate. </div>展开更多
Goldfish(Carassius auratus auratus)are important ornamental fish that have experienced extreme anthropogenic selection and exhibit diverse phenotypes.Loss of the dorsal fin is a key characteristic that distinguishes t...Goldfish(Carassius auratus auratus)are important ornamental fish that have experienced extreme anthropogenic selection and exhibit diverse phenotypes.Loss of the dorsal fin is a key characteristic that distinguishes the Egg-goldfish from the Wen-goldfish.However,the mechanisms underlying the divergence in dorsal fin development are still unknown between the Egg-goldfish and the Wen-goldfish.In this study,we sought to unravel the postembryonic developmental processes of two goldfish strains,Red Cap Oranda,a representative of the Wen-goldfish,and Ranchu,a representative of the Egg-goldfish.We examined the developmental morphology of the dorsal fin in five-month-old goldfish larvae using both Alcian blue-alizarin red staining and X-ray photography.We showed that the developmental processes of the dorsal fin fold were different in Ranchu compared to Red Cap Oranda,despite similarity in their general developmental processes.We categorized the postembryonic development of Ranchu larvae into four types based on the number of the initial residual dorsal fin fold appearing at protruding-mouth stage.The number,size and position of the initial residual dorsal fin fold appeared at hatching affected and eventually determined the phenotypic variations in dorsal fin defects in Ranchu.In addition,we genotyped the eomesa gene to determine whether it would be a candidate gene responsible for the loss of the dorsal fin in Ranchu.The eomesa CDS sequence exhibited no nonsense mutation in Ranchu.In summary,the absence of the dorsal fin fold during postembryonic development eventually resulted in the loss of the dorsal fin in Ranchu.Further investigation is required to determine whether other genes and developmental pathways play important roles in the loss of the dorsal fin in Ranchu.展开更多
文摘<div style="text-align:justify;"> Due to the poor anti-clogging performance of the common drip irrigation emitters, this paper designed a new bionic flow channel in the emitter based on the shape of shark dorsal fin. After preliminary structural design, the computational fluid dynamics (CFD) simulation showed that the bionic emitter exhibited superior anti-clogging performance and reasonable hydraulic performance. The passage rate of particles of the bionic emitter in simulation reached 96.3% which was 37.6% higher than 70% of traditional emitter, and the discharge exponent reached 0.4995 which was close to traditional emitter. Physical experiments were consistent with the CFD results, which confirmed the correctness of simulation. After a short cycle anti-clogging performance experiment, the bionic emitter still maintained 96.09% of the initial flow rate. </div>
基金This work was financially supported by the SHOU&MSU Joint Research Center grant.
文摘Goldfish(Carassius auratus auratus)are important ornamental fish that have experienced extreme anthropogenic selection and exhibit diverse phenotypes.Loss of the dorsal fin is a key characteristic that distinguishes the Egg-goldfish from the Wen-goldfish.However,the mechanisms underlying the divergence in dorsal fin development are still unknown between the Egg-goldfish and the Wen-goldfish.In this study,we sought to unravel the postembryonic developmental processes of two goldfish strains,Red Cap Oranda,a representative of the Wen-goldfish,and Ranchu,a representative of the Egg-goldfish.We examined the developmental morphology of the dorsal fin in five-month-old goldfish larvae using both Alcian blue-alizarin red staining and X-ray photography.We showed that the developmental processes of the dorsal fin fold were different in Ranchu compared to Red Cap Oranda,despite similarity in their general developmental processes.We categorized the postembryonic development of Ranchu larvae into four types based on the number of the initial residual dorsal fin fold appearing at protruding-mouth stage.The number,size and position of the initial residual dorsal fin fold appeared at hatching affected and eventually determined the phenotypic variations in dorsal fin defects in Ranchu.In addition,we genotyped the eomesa gene to determine whether it would be a candidate gene responsible for the loss of the dorsal fin in Ranchu.The eomesa CDS sequence exhibited no nonsense mutation in Ranchu.In summary,the absence of the dorsal fin fold during postembryonic development eventually resulted in the loss of the dorsal fin in Ranchu.Further investigation is required to determine whether other genes and developmental pathways play important roles in the loss of the dorsal fin in Ranchu.
