A class of nonlinear global climate oscillation models is considered. Using perturbation theory and its methods, solutions to the asymptotic expansions of some related problems are constructed. These asymptotic expans...A class of nonlinear global climate oscillation models is considered. Using perturbation theory and its methods, solutions to the asymptotic expansions of some related problems are constructed. These asymptotic expansions of the solutions for the original problem possess a higher approximation. The perturbed asymptotic method is an analyti cmethod.展开更多
目的了解汕头市水产品非O1/O139群霍乱弧菌的耐药基因、毒力基因、序列位点信息,分析不同菌株间遗传关系。方法收集分离自水产品的霍乱弧菌41株,对菌株进行全基因组序列测定,利用生物信息学工具预测菌株的耐药基因和毒力基因情况,结合...目的了解汕头市水产品非O1/O139群霍乱弧菌的耐药基因、毒力基因、序列位点信息,分析不同菌株间遗传关系。方法收集分离自水产品的霍乱弧菌41株,对菌株进行全基因组序列测定,利用生物信息学工具预测菌株的耐药基因和毒力基因情况,结合美国国家生物技术信息中心(National Center for Biotechnology Information,NCBI)数据库,进行多位点序列分型分析(multilocus sequence typing,MLST)和核心基因组单核苷酸多态性分析(core gene single nucleotide polymorphism,cgSNP)。结果41株霍乱弧菌共检测到34个抗生素耐药基因,携带率最高的是dfrA31(46.3%),部分菌株携带能水解所有β-内酰胺酶的blaNDM-1基因。毒力基因携带率最高的是rtxA(100.0%)和hlyA(97.6%),所有病原菌株均不携带ctxA和ctxB,致病岛VPI-1/VPI-2携带率分别为31.7%/70.7%,T6SS和第7次大流行特征基因岛VSP-1/VSP-2的检出率都是4.9%。MLST和cgSNP分析显示,共有30种不同的序列型(sequencetypes,STs),其中20种为新分配的STs。结论汕头市水产品中非O1/O139群霍乱弧菌携带多种毒力基因和耐药基因,其中霍乱弧菌携带blaNDM-1基因为国内首次报道。不同物种来源的菌株遗传多样性高,发现大量新STs型。展开更多
Atmospheric physics is a very complicated natural phenomenon and needs to simplify its basic models for the sea-air oscillator. And it is solved by using the approximate method. The variational iteration method is a s...Atmospheric physics is a very complicated natural phenomenon and needs to simplify its basic models for the sea-air oscillator. And it is solved by using the approximate method. The variational iteration method is a simple and valid method. In this paper the coupled system for a sea-air oscillator model of interdecadal climate fluctuations is considered. Firstly, through introducing a set of functions, and computing the variations, the Lagrange multipliers are obtained. And then, the generalized expressions of variational iteration are constructed. Finally, through selecting appropriate initial iteration from the iteration expressions, the approximations of solution for the sea-air oscillator model are solved successively.展开更多
In this paper,a class of coupled system for the E1 Nifio/La Nifia southern oscillation(ENSO)atmospheric physics oscillation model is considered.We propose an ENSO atmospheric physics model using a method from the asym...In this paper,a class of coupled system for the E1 Nifio/La Nifia southern oscillation(ENSO)atmospheric physics oscillation model is considered.We propose an ENSO atmospheric physics model using a method from the asymptotic theory.It is indicated from the results that the asymptotic method can be used for analyzing the sea surface temperature anomaly and the thermocline depth anomaly of the atmosphere-ocean oscillation for the ENSO model in the equatorial Pacific.展开更多
A set of numerical experiments is designed and carried out to understand a heat sink in the Southern Ocean in the recent hiatus decade. By using an oceanic general circulation model, the authors focus on the contribut...A set of numerical experiments is designed and carried out to understand a heat sink in the Southern Ocean in the recent hiatus decade. By using an oceanic general circulation model, the authors focus on the contributions from two types of forcing: wind stress and thermohaline forcing. The simulated results show that the heat sink in the upper Southern Ocean comes mainly from thermohaline forcing; while in the deeper layers, wind stress forcing also plays an important role. These different contributions may be due to different physical processes for the heat budget. The combination of these two types of forcing shows a significant heat sink in the Southern Ocean in the recent hiatus decade, and this is consistent with the observations and conclusions of a similar recently published study.展开更多
基金supported by the support of the National Natural Science Foundation of China (Grant No. 40676016)the State Key Development Program for Basic Research of China (Grant Nos. 2003CB415101-03, 2004CB418304)+1 种基金the Key of the Knowledge Innovation of the Chinese Academy of Sciences (Grant No. KZCX3-SW-221)in part, by the E-Institutes of Shanghai Municipal Education Commission (Grant No. E03004)
文摘A class of nonlinear global climate oscillation models is considered. Using perturbation theory and its methods, solutions to the asymptotic expansions of some related problems are constructed. These asymptotic expansions of the solutions for the original problem possess a higher approximation. The perturbed asymptotic method is an analyti cmethod.
文摘目的了解汕头市水产品非O1/O139群霍乱弧菌的耐药基因、毒力基因、序列位点信息,分析不同菌株间遗传关系。方法收集分离自水产品的霍乱弧菌41株,对菌株进行全基因组序列测定,利用生物信息学工具预测菌株的耐药基因和毒力基因情况,结合美国国家生物技术信息中心(National Center for Biotechnology Information,NCBI)数据库,进行多位点序列分型分析(multilocus sequence typing,MLST)和核心基因组单核苷酸多态性分析(core gene single nucleotide polymorphism,cgSNP)。结果41株霍乱弧菌共检测到34个抗生素耐药基因,携带率最高的是dfrA31(46.3%),部分菌株携带能水解所有β-内酰胺酶的blaNDM-1基因。毒力基因携带率最高的是rtxA(100.0%)和hlyA(97.6%),所有病原菌株均不携带ctxA和ctxB,致病岛VPI-1/VPI-2携带率分别为31.7%/70.7%,T6SS和第7次大流行特征基因岛VSP-1/VSP-2的检出率都是4.9%。MLST和cgSNP分析显示,共有30种不同的序列型(sequencetypes,STs),其中20种为新分配的STs。结论汕头市水产品中非O1/O139群霍乱弧菌携带多种毒力基因和耐药基因,其中霍乱弧菌携带blaNDM-1基因为国内首次报道。不同物种来源的菌株遗传多样性高,发现大量新STs型。
文摘Atmospheric physics is a very complicated natural phenomenon and needs to simplify its basic models for the sea-air oscillator. And it is solved by using the approximate method. The variational iteration method is a simple and valid method. In this paper the coupled system for a sea-air oscillator model of interdecadal climate fluctuations is considered. Firstly, through introducing a set of functions, and computing the variations, the Lagrange multipliers are obtained. And then, the generalized expressions of variational iteration are constructed. Finally, through selecting appropriate initial iteration from the iteration expressions, the approximations of solution for the sea-air oscillator model are solved successively.
基金Project supported by the National Natural Science Foundation of China(Grant No.40876010)the Strategic Priority Research Program-Climate Change:Carbon Budget and Relevant Issues of the Chinese Academy of Sciences(Grant No.XDA01020304)+2 种基金the Natural Science Foundation from the Education Bureau of Anhui Province,China(Grant No.KJ2011A135)the Natural Science Foundation of Zhejiang Province,China(Grant No.Y6110502)the Natural Science Foundation of Jiangsu Province,China(Grant No.BK2011042)
文摘In this paper,a class of coupled system for the E1 Nifio/La Nifia southern oscillation(ENSO)atmospheric physics oscillation model is considered.We propose an ENSO atmospheric physics model using a method from the asymptotic theory.It is indicated from the results that the asymptotic method can be used for analyzing the sea surface temperature anomaly and the thermocline depth anomaly of the atmosphere-ocean oscillation for the ENSO model in the equatorial Pacific.
基金supported by the National Natural Science Foundation of China (Grant No. 41175058)the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA11010404)
文摘A set of numerical experiments is designed and carried out to understand a heat sink in the Southern Ocean in the recent hiatus decade. By using an oceanic general circulation model, the authors focus on the contributions from two types of forcing: wind stress and thermohaline forcing. The simulated results show that the heat sink in the upper Southern Ocean comes mainly from thermohaline forcing; while in the deeper layers, wind stress forcing also plays an important role. These different contributions may be due to different physical processes for the heat budget. The combination of these two types of forcing shows a significant heat sink in the Southern Ocean in the recent hiatus decade, and this is consistent with the observations and conclusions of a similar recently published study.
