以军团菌DNA为模板,PCR扩增获得军团菌主要外膜蛋白基因(M a jor ou ter m em brane prote in gene,om pS),与原核表达质粒pUC 18定向重组,构建重组质粒,转化大肠杆菌BL 21,并用限制性酶酶切分析、聚合酶链式反应、核酸序列分析、十二...以军团菌DNA为模板,PCR扩增获得军团菌主要外膜蛋白基因(M a jor ou ter m em brane prote in gene,om pS),与原核表达质粒pUC 18定向重组,构建重组质粒,转化大肠杆菌BL 21,并用限制性酶酶切分析、聚合酶链式反应、核酸序列分析、十二烷基磺酸钠-聚丙烯酰胺凝胶电泳、W estern印迹进行鉴定。实验结果表明我们扩增出了军团菌914 bp的om pS基因,成功构建了重组质粒pLPom pS,并在原核系统中得到了表达。展开更多
Two statistical validation methods were used to evaluate the confidence level of the Total Column Ozone (TCO) measurements recorded by satellite systems measuring simultaneously, one using the normal distribution and ...Two statistical validation methods were used to evaluate the confidence level of the Total Column Ozone (TCO) measurements recorded by satellite systems measuring simultaneously, one using the normal distribution and another using the Mann-Whitney test. First, the reliability of the TCO measurements was studied hemispherically. While similar coincidences and levels of significance > 0.05 were found with the two statistical tests, an enormous variability in the levels of significance throughout the year was also exposed. Then, using the same statistical comparison methods, a latitudinal study was carried out in order to elucidate the geographical distribution that gave rise to this variability. Our study reveals that between the TOMS and OMI measurements in 2005 there was only a coincidence in 50% of the latitudes, which explained the variability. This implies that for 2005, the TOMS measurements are not completely reliable, except between the -50° and -15° latitude band in the southern hemisphere and between +15° and +50° latitude band in the northern hemisphere. In the case of OMI-OMPS, we observe that between 2011 and 2016 the measurements of both satellite systems are reasonably similar with a confidence level higher than 95%. However, in 2017 a band with a width of 20° latitude centered on the equator appeared, in which the significance levels were much less than 0.05, indicating that one of the measurement systems had begun to fail. In 2018, the fault was not only located in the equator, but was also replicated in various bands in the Southern Hemisphere. We interpret this as evidence of irreversible failure in one of the measurement systems.展开更多
文摘以军团菌DNA为模板,PCR扩增获得军团菌主要外膜蛋白基因(M a jor ou ter m em brane prote in gene,om pS),与原核表达质粒pUC 18定向重组,构建重组质粒,转化大肠杆菌BL 21,并用限制性酶酶切分析、聚合酶链式反应、核酸序列分析、十二烷基磺酸钠-聚丙烯酰胺凝胶电泳、W estern印迹进行鉴定。实验结果表明我们扩增出了军团菌914 bp的om pS基因,成功构建了重组质粒pLPom pS,并在原核系统中得到了表达。
文摘Two statistical validation methods were used to evaluate the confidence level of the Total Column Ozone (TCO) measurements recorded by satellite systems measuring simultaneously, one using the normal distribution and another using the Mann-Whitney test. First, the reliability of the TCO measurements was studied hemispherically. While similar coincidences and levels of significance > 0.05 were found with the two statistical tests, an enormous variability in the levels of significance throughout the year was also exposed. Then, using the same statistical comparison methods, a latitudinal study was carried out in order to elucidate the geographical distribution that gave rise to this variability. Our study reveals that between the TOMS and OMI measurements in 2005 there was only a coincidence in 50% of the latitudes, which explained the variability. This implies that for 2005, the TOMS measurements are not completely reliable, except between the -50° and -15° latitude band in the southern hemisphere and between +15° and +50° latitude band in the northern hemisphere. In the case of OMI-OMPS, we observe that between 2011 and 2016 the measurements of both satellite systems are reasonably similar with a confidence level higher than 95%. However, in 2017 a band with a width of 20° latitude centered on the equator appeared, in which the significance levels were much less than 0.05, indicating that one of the measurement systems had begun to fail. In 2018, the fault was not only located in the equator, but was also replicated in various bands in the Southern Hemisphere. We interpret this as evidence of irreversible failure in one of the measurement systems.
文摘针对工作在毫米波频段下的去蜂窝大规模多输入多输出(cell-free massive multiple-input multipleoutput,CF-mMIMO)系统中混合预编码设计面临的链路开销大与数值不稳定等问题,提出了一种适配分布式架构的基于列正交约束的正交匹配追踪(orthogonal matching pursuit,OMP)算法。在模拟预编码阶段,采用基于旋转不变性技术的信号参数最小二乘估计(least squares estimation of signal parameters via rotational invariance technique,LS-ESPRIT)算法,基于接收信号直接估计信号到达角,并重构波束码本,有效压缩了反馈开销;在数字预编码阶段,引入列正交约束并推导了最优因子,重构了优化目标函数,规避了病态矩阵求逆问题,提升了预编码矩阵的数值稳定性与匹配精度。仿真结果表明,该算法在不同接入点分布结构与系统参数设置下均能保持稳定且明显的频谱效率性能提升,验证了其在CF-mMIMO系统中的鲁棒性与优越性。
