This paper intends to promote a college English autonomous teaching and learning approach by introducing the whole process of its implementation and feedback from the learners. The theoretical and practical framework ...This paper intends to promote a college English autonomous teaching and learning approach by introducing the whole process of its implementation and feedback from the learners. The theoretical and practical framework of this approach is： with multiple autonomous learning research and practice models as its core, with process syllabus as its guidance, with task-based teaching as its essential principle, with group cooperation and reciprocal learning as its means, with extracurricular activities, online learning and self-access center as its learning environment, with formative assessment system as its guarantee and with cultivation of learners＇ comprehensive English practical skills and autonomy as its goal. Through this approach, we provide the learners with a favorable learning environment where they can learn by themselves and learn by reflection and practice so that they can learn how to learn and how to behave and how to survive.展开更多
Life cycle of the trematode worm, Exorchis mupingensis, includes Oncomelania hupensis snail as first intermediate host and several small freshwater fishes as second intermediate hosts, while the carnivorous fish, Para...Life cycle of the trematode worm, Exorchis mupingensis, includes Oncomelania hupensis snail as first intermediate host and several small freshwater fishes as second intermediate hosts, while the carnivorous fish, Parasilurus asotus, serves as a final host of this parasite. P. asotus fish, Labidochromis caeruleus fish and E. mupingensis cercariae were used in the laboratory to determine the time that mature metacercariae of E. mupingensis take to develop into an adult worm within the final host. Results showed that the period of development of the mature metacercariae of E. mupingensis into an adult worm within the final host, P. asotus, is ca. 30 d.展开更多
Fish ectoparasites are introduced to water bodies or aquaculture systems along with their hosts. Argulid fish lice can survive off-host for a given time, and in spite of quarantine measures might also be introduced vi...Fish ectoparasites are introduced to water bodies or aquaculture systems along with their hosts. Argulid fish lice can survive off-host for a given time, and in spite of quarantine measures might also be introduced via the transfer of water. However, they must cope with varying abiotic conditions without access to food. We investigated the effect of temperature （5 to 28℃） on the off-host survival time of Argulus japonicus, an invasive species which is apparently increasing its distribution, and compared this with the European A. foliaceus. A clear effect of temperature on the off-host survival time of all stages of both species was demonstrated. Larval and juvenile A. japonicus survived up to 9 days at 22℃ and in the case of adults up to 13 days at 15℃. By comparison, larval A. foliaceus survived up to 5 days at 15℃, adults up to 14 days at 9℃ and juveniles up to 7 days at 9℃ and 15℃. Thus, A. japonicus is more resistant to starvation at higher temperatures under controlled off-host conditions and A. foli- aceus is more resistant to starvation at lower temperatures. Infectivity of A. japonicus decreased linearly with the time spent off-host after 2 days for larvae and 4 days for adults. Temperature only had a significant effect on the infectivity of both develop- mental stages after 24 hours off-host between 13-23℃ for larvae and 13-18℃ for adults. In conclusion both species can potentially survive off-host pelods in water transports for up to 13-14 days as adults. Their survival is shorter as larvae. This study demonstrates that transportation of water has the potential to introduce Argulus species展开更多
文摘This paper intends to promote a college English autonomous teaching and learning approach by introducing the whole process of its implementation and feedback from the learners. The theoretical and practical framework of this approach is： with multiple autonomous learning research and practice models as its core, with process syllabus as its guidance, with task-based teaching as its essential principle, with group cooperation and reciprocal learning as its means, with extracurricular activities, online learning and self-access center as its learning environment, with formative assessment system as its guarantee and with cultivation of learners＇ comprehensive English practical skills and autonomy as its goal. Through this approach, we provide the learners with a favorable learning environment where they can learn by themselves and learn by reflection and practice so that they can learn how to learn and how to behave and how to survive.
基金Acknowledgments The authors thank the staff of Animal Diseases Institute, Hanshou, Hunan province, China, for their assistance during the field work. This research was funded by the National Natural Science Foundation of China （No. 31270938）.
文摘Life cycle of the trematode worm, Exorchis mupingensis, includes Oncomelania hupensis snail as first intermediate host and several small freshwater fishes as second intermediate hosts, while the carnivorous fish, Parasilurus asotus, serves as a final host of this parasite. P. asotus fish, Labidochromis caeruleus fish and E. mupingensis cercariae were used in the laboratory to determine the time that mature metacercariae of E. mupingensis take to develop into an adult worm within the final host. Results showed that the period of development of the mature metacercariae of E. mupingensis into an adult worm within the final host, P. asotus, is ca. 30 d.
文摘Fish ectoparasites are introduced to water bodies or aquaculture systems along with their hosts. Argulid fish lice can survive off-host for a given time, and in spite of quarantine measures might also be introduced via the transfer of water. However, they must cope with varying abiotic conditions without access to food. We investigated the effect of temperature （5 to 28℃） on the off-host survival time of Argulus japonicus, an invasive species which is apparently increasing its distribution, and compared this with the European A. foliaceus. A clear effect of temperature on the off-host survival time of all stages of both species was demonstrated. Larval and juvenile A. japonicus survived up to 9 days at 22℃ and in the case of adults up to 13 days at 15℃. By comparison, larval A. foliaceus survived up to 5 days at 15℃, adults up to 14 days at 9℃ and juveniles up to 7 days at 9℃ and 15℃. Thus, A. japonicus is more resistant to starvation at higher temperatures under controlled off-host conditions and A. foli- aceus is more resistant to starvation at lower temperatures. Infectivity of A. japonicus decreased linearly with the time spent off-host after 2 days for larvae and 4 days for adults. Temperature only had a significant effect on the infectivity of both develop- mental stages after 24 hours off-host between 13-23℃ for larvae and 13-18℃ for adults. In conclusion both species can potentially survive off-host pelods in water transports for up to 13-14 days as adults. Their survival is shorter as larvae. This study demonstrates that transportation of water has the potential to introduce Argulus species
