Environmental conditions, including ambient temperature, play important roles in survival growth development, and reproduction of the Japanese sea cucumber, Apostichopus japonicus. Low temperatures result in slowed gr...Environmental conditions, including ambient temperature, play important roles in survival growth development, and reproduction of the Japanese sea cucumber, Apostichopus japonicus. Low temperatures result in slowed growth and skin ulceration disease. In a previous study, we investigated the effect of low temperature on gene expression profiles inA.japonicus by suppression subtractive hybridization （SSH）. Genes encoding Ferritin, Lysozyme, Hsp70, gp96, and AjToll were selected from a subtracted cDNA library of A. japonicus under acute cold stress. The transcriptional expression profiles of these genes were investigated in different tissues （coelomocyte, respiratory tree, intestine, longitudinal muscle） after exposure to acute and mild temperature dropping treatments. The results show that （1） the five cold-tolerance-related genes were found in all four tissues and the highest mRNA levels were observed in coelomocyte and respiratory tree; （2） under the temperature dropping treatments, three types of transcriptional regulation patterns were observed： primary suppression followed by up-regulation at -2℃, suppressed expression throughout the two treatments, and more rarely an initial stimulation followed by suppression; and （3） gene expression suppression was more severe under acute temperature dropping than under mild temperature dropping treatment. The five cold-tolerance-related genes that were ,distributed mainly in coelomocyte and respiratory tissues were generally down-regulated by low temperature stress but an inverse up-regulation event was found at the extreme temperature （-2℃）.展开更多
It is helpful to improve the seismic design theory of long-span continuous bridges for studying the seismic performance of each cantilever construction state.Taking the Bridge 1 in the north of Changbai-Mountain inter...It is helpful to improve the seismic design theory of long-span continuous bridges for studying the seismic performance of each cantilever construction state.Taking the Bridge 1 in the north of Changbai-Mountain international tourism resort as an example,the authors studied it in shutdown phase and the cantilever construction process,established the simulation model by using Midas / civil,and analyzed time-history of each construction stage for the bridge.The study shows that long-span bridge cantilever construction in northeastern China can be divided into two-year tasks for construction(suspending in winter).It is needed to think about seismic stability of the cantilever position in shut-down phase of winter.The effect of longitudinal vibration is the most disadvantageous influence to bridge,and its calculation results can provide reference for seismic design of similar bridges in the future.展开更多
基金Supported by the National High Technology Research and Development Program of China(863 Program)(No.2012AA10A412)the National Natural Science Foundation of China(No.31072230)
文摘Environmental conditions, including ambient temperature, play important roles in survival growth development, and reproduction of the Japanese sea cucumber, Apostichopus japonicus. Low temperatures result in slowed growth and skin ulceration disease. In a previous study, we investigated the effect of low temperature on gene expression profiles inA.japonicus by suppression subtractive hybridization （SSH）. Genes encoding Ferritin, Lysozyme, Hsp70, gp96, and AjToll were selected from a subtracted cDNA library of A. japonicus under acute cold stress. The transcriptional expression profiles of these genes were investigated in different tissues （coelomocyte, respiratory tree, intestine, longitudinal muscle） after exposure to acute and mild temperature dropping treatments. The results show that （1） the five cold-tolerance-related genes were found in all four tissues and the highest mRNA levels were observed in coelomocyte and respiratory tree; （2） under the temperature dropping treatments, three types of transcriptional regulation patterns were observed： primary suppression followed by up-regulation at -2℃, suppressed expression throughout the two treatments, and more rarely an initial stimulation followed by suppression; and （3） gene expression suppression was more severe under acute temperature dropping than under mild temperature dropping treatment. The five cold-tolerance-related genes that were ,distributed mainly in coelomocyte and respiratory tissues were generally down-regulated by low temperature stress but an inverse up-regulation event was found at the extreme temperature （-2℃）.
文摘It is helpful to improve the seismic design theory of long-span continuous bridges for studying the seismic performance of each cantilever construction state.Taking the Bridge 1 in the north of Changbai-Mountain international tourism resort as an example,the authors studied it in shutdown phase and the cantilever construction process,established the simulation model by using Midas / civil,and analyzed time-history of each construction stage for the bridge.The study shows that long-span bridge cantilever construction in northeastern China can be divided into two-year tasks for construction(suspending in winter).It is needed to think about seismic stability of the cantilever position in shut-down phase of winter.The effect of longitudinal vibration is the most disadvantageous influence to bridge,and its calculation results can provide reference for seismic design of similar bridges in the future.
