A prediction model of the deepwater steel catenary riser VIV is proposed based on the forced oscillation test data, taking into account the riser-seafloor interaction for the cross-flow VIV-induced fatigue damage at t...A prediction model of the deepwater steel catenary riser VIV is proposed based on the forced oscillation test data, taking into account the riser-seafloor interaction for the cross-flow VIV-induced fatigue damage at touch-down point （TDP）. The model will give more reasonable simulation of SCR response near TDP than the previous pinned truncation model. In the present model, the hysteretic riser-soil interaction model is simplified as the linear spring and damper to simulate the seafloor, and the damping is obtained according to the dissipative power during one periodic riser-soil interaction. In order to validate the model, the comparison with the field measurement and the results predicted by Shear 7 program of a full-scale steel catenary riser is carried out. The main induced modes, mode frequencies and response amplitude are in a good agreement. Furthermore, the parametric studies are carried out to broaden the understanding of the fatigue damage sensitivity to the upper end in-plane offset and seabed characteristics. In addition, the fatigue stress comparison at TDP between the truncation riser model and the present full riser model shows that the existence of touch-down zones is very important for the fatigue damage assessment of steel catenary riser at TDP.展开更多
目的：探索高GC含量DNA的PCR扩增条件，为扩增达托霉素生物合成基因簇及拼接奠定基础。方法：在PCR扩增体系中，使用高保真的聚合酶及添加不同浓度的DMSO、7-deaza-dGTP等增强剂，并选择合适的PCR循环程序，优化富含GC的DNA的PCR扩增条...目的：探索高GC含量DNA的PCR扩增条件，为扩增达托霉素生物合成基因簇及拼接奠定基础。方法：在PCR扩增体系中，使用高保真的聚合酶及添加不同浓度的DMSO、7-deaza-dGTP等增强剂，并选择合适的PCR循环程序，优化富含GC的DNA的PCR扩增条件。结果：向反应体系中额外添加1%~4%的DMSO可以显著提高富含GC的DNA的PCR扩增产物量，但会降低其特异性；7-deaza-dGTP可以提高扩增产物的特异性及保真度，但产量会有所下降。应用touch down PCR并在体系中添加7-deaza-dGTP能够提高扩增产物的特异性和产率，增加扩增的保真度。结论：应用优化的PCR扩增条件将所有达托霉素生物合成基因簇分段扩增出来，并可扩增出长达6 kb的片段，且序列完全正确，可以进行后续拼接。展开更多
Through exploring the microsatellite primers from the random genome sequences of Chinese shrimp （Fenneropenaeus chinensis）, some microsatellite primers were obtained with rich polymorphic genetic information, and a ...Through exploring the microsatellite primers from the random genome sequences of Chinese shrimp （Fenneropenaeus chinensis）, some microsatellite primers were obtained with rich polymorphic genetic information, and a triplex PCR was established using three primers （RS1101, RS0683 and H081 primers）. By adjusting the final concentration of Mg^2＋, dNTP and primers, and using a touch-town PCR program, the optimum amplification parameters of PCR system were obtained, which could successfully amplify the three primers in a PCR reaction. In the denatured PAGE gel, the amplified DNA fragments of three primers RS1 101,RS0683 and H081 could be easily identified each other. For the triplex PCR system, the PPE （probabilities of paternity exclusion） is 0.967 9,and the DP （discrimination power） is 0.999 327.Using the triplex PCR to test ten individuals of a parentage and their parents, an individual was excluded from the parentage in all of the three microsatellite loci, which might be mixed into the parentage for some unknown reason such as factitious misplay. The triplex PCR will be of great practical value in identifying the parentages of F. chinensis.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.51009089)the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20100073120017)
文摘A prediction model of the deepwater steel catenary riser VIV is proposed based on the forced oscillation test data, taking into account the riser-seafloor interaction for the cross-flow VIV-induced fatigue damage at touch-down point （TDP）. The model will give more reasonable simulation of SCR response near TDP than the previous pinned truncation model. In the present model, the hysteretic riser-soil interaction model is simplified as the linear spring and damper to simulate the seafloor, and the damping is obtained according to the dissipative power during one periodic riser-soil interaction. In order to validate the model, the comparison with the field measurement and the results predicted by Shear 7 program of a full-scale steel catenary riser is carried out. The main induced modes, mode frequencies and response amplitude are in a good agreement. Furthermore, the parametric studies are carried out to broaden the understanding of the fatigue damage sensitivity to the upper end in-plane offset and seabed characteristics. In addition, the fatigue stress comparison at TDP between the truncation riser model and the present full riser model shows that the existence of touch-down zones is very important for the fatigue damage assessment of steel catenary riser at TDP.
文摘目的：探索高GC含量DNA的PCR扩增条件，为扩增达托霉素生物合成基因簇及拼接奠定基础。方法：在PCR扩增体系中，使用高保真的聚合酶及添加不同浓度的DMSO、7-deaza-dGTP等增强剂，并选择合适的PCR循环程序，优化富含GC的DNA的PCR扩增条件。结果：向反应体系中额外添加1%~4%的DMSO可以显著提高富含GC的DNA的PCR扩增产物量，但会降低其特异性；7-deaza-dGTP可以提高扩增产物的特异性及保真度，但产量会有所下降。应用touch down PCR并在体系中添加7-deaza-dGTP能够提高扩增产物的特异性和产率，增加扩增的保真度。结论：应用优化的PCR扩增条件将所有达托霉素生物合成基因簇分段扩增出来，并可扩增出长达6 kb的片段，且序列完全正确，可以进行后续拼接。
基金This study was supported by the National High-Tech Research and Development Program of China(863)under contract No.2005AA603210the National"948"Foundation of China under contract No.2006-G55(B)+2 种基金the National Natural Science Foundation of China under contract No.30500378the 0pen-end Funds of Jiangsu Key Laboratory of Marine Biotechnology,the Huaihai Institute of Technology under contract No.2006HS004the 0pen-end Funds of Key Laboratory of Aquatic Genetic Resources and Aquacultural Ecosystem of the Ministry of Agriculture of China,Shanghai Fisheries University under contract No.KFT2006-6.
文摘Through exploring the microsatellite primers from the random genome sequences of Chinese shrimp （Fenneropenaeus chinensis）, some microsatellite primers were obtained with rich polymorphic genetic information, and a triplex PCR was established using three primers （RS1101, RS0683 and H081 primers）. By adjusting the final concentration of Mg^2＋, dNTP and primers, and using a touch-town PCR program, the optimum amplification parameters of PCR system were obtained, which could successfully amplify the three primers in a PCR reaction. In the denatured PAGE gel, the amplified DNA fragments of three primers RS1 101,RS0683 and H081 could be easily identified each other. For the triplex PCR system, the PPE （probabilities of paternity exclusion） is 0.967 9,and the DP （discrimination power） is 0.999 327.Using the triplex PCR to test ten individuals of a parentage and their parents, an individual was excluded from the parentage in all of the three microsatellite loci, which might be mixed into the parentage for some unknown reason such as factitious misplay. The triplex PCR will be of great practical value in identifying the parentages of F. chinensis.
