The observation data from ground surface meteorological stations is an important basis on which climate change research is carried out, while the homogenization of the data is necessary for improving the quality and h...The observation data from ground surface meteorological stations is an important basis on which climate change research is carried out, while the homogenization of the data is necessary for improving the quality and homogeneity of the time series. This paper reviews recent advances in the techniques of identifying and adjusting inhomogeneity in climate series. We briefly introduce the results of applying two commonly accepted and well-developed methods (RHtest and MASH) to surface climate observations such as temperature and wind speed in China. We then summarize current progress and problems in this field, and propose ideas for future studies in China. Along with collecting more detailed metadata, more research on homogenization technology should be done in the future. On the basis of comparing and evaluating advantages and disadvantages of different homogenization methods, the homogenized climate data series of the last hundred years should be rebuilt.展开更多
Cardiac resynchronization therapy (CRT) is associated with a favorable outcome only in patients with left bundle branch block (LBBB) pattern and in patients with a QRS duration 〉 150 ms, in patients with non-LBBB...Cardiac resynchronization therapy (CRT) is associated with a favorable outcome only in patients with left bundle branch block (LBBB) pattern and in patients with a QRS duration 〉 150 ms, in patients with non-LBBB pattern with a QRS duration of 120-150 ms usually is not beneficial. After adjusting for QRS duration, QRS morphology was no longer a determinant of the clinical response to CRT. In contrast to the mainstream view, we hypothesized that the unfavorable CRT outcome in patients with non-LBBB and a QRS duration of 120-150 ms is not due to the QRS morphology itself, but to less dyssynchrony and unfavorable patient characteristics in this subgroup, such as more ischemic etiology and greater prevalence of male patients compared with patients with LBBB pattern. Further, the current CRT technique is devised to eliminate the dyssynchrony present in patients with LBBB pattern and inappropriate to eliminate the dyssynchrony in patients with non-LBBB pattern. We also hypothesized that electrocardiography may also provide information about the presence of interventricular and left intraventricular dyssynchrony and the approximate location of the latest activated left ventricular (LV) region. To this end, we devised new ECG criteria to estimate interventricular and LV intraventricular dyssynchrony and the approximate location of the latest activated LV region. Our preliminary data demonstrated that the latest activated LV region in patients with nonspecific intraventricular conduction disturbance (NICD) pattern might be at a remote site from that present in patients with LBBB pattern, which might necessitate the invention of a novel CRT technique for patients with NICD pattern. The application of the new interventricular and LV intraventricular dyssynchrony ECG criteria and a potential novel CRT technique might decrease the currently high nonresponder rate in patients with NICD pattern.展开更多
The expression of mRNA for bone morphogenetic protein-1 (BMP-1) was investigated in fetal human cartilage and bone during the developing endochondral ossification by using in situ hybridization. BMP-1 mRNA was localiz...The expression of mRNA for bone morphogenetic protein-1 (BMP-1) was investigated in fetal human cartilage and bone during the developing endochondral ossification by using in situ hybridization. BMP-1 mRNA was localized in the hypertrophic chondrocytes, the cells of perichondrium, osteoblasts and marrow cells. The results suggest that BMP-1 may involve in cartilage and bone formation, and in regulation of calcification of growth plate.As a comparative study, the expression of TGF-β1 protein was investigated in cartilage and bone using immunohistochemical staining, correlated expression of TGF-β1 and BMP-1 was found. The results suggest that BMP-1 and TGF-β1 act synergistically to influence endochrondral ossification.展开更多
Synchronization in coupled oscillator networks has attracted much attention from many fields of science and engineering. In this paper, it is firstly proved that the oscifiator network with nonlinear coupling is also ...Synchronization in coupled oscillator networks has attracted much attention from many fields of science and engineering. In this paper, it is firstly proved that the oscifiator network with nonlinear coupling is also eventually dissipative under the hypothesis of eventual dissipation of the uncoupled oscillators. And the dynamics of the network is analyzed in its absorbing domain by combining two methods developed recently. Suufficient conditions for synchronization in the oscillator networks with nonlinear coupling are obtained. The two methods are combined effectively and the results embody the respective merits of the two methods. Numerical simulations confirm the validity of the results.展开更多
Cascaded multilevel converters built with integrated modules have many advantages such as increased power density,flexible distributed control,multi-functionality,increased reliability and short design cycles.However,...Cascaded multilevel converters built with integrated modules have many advantages such as increased power density,flexible distributed control,multi-functionality,increased reliability and short design cycles.However,the system performance will be affected due to the synchronization errors among each integrated modules.This paper analyzes the impact of the three kinds of synchronization errors on the whole system performance,as well as detailed synchronization implementation.Some valuable conclusions are derived from the theoretical analysis,simulations and experimental results.展开更多
基金supported by the National Program on Key Basic Research Project (No. 2010CB951602, 2009CB421401)National Science and Technology Ministry (No. 2008BAK50B07)+1 种基金China Special Fund for Meteorological Research in the Public Interest (No. 200906041-052)the Project of National Natural Science Foundation of China (No. 40805060)
文摘The observation data from ground surface meteorological stations is an important basis on which climate change research is carried out, while the homogenization of the data is necessary for improving the quality and homogeneity of the time series. This paper reviews recent advances in the techniques of identifying and adjusting inhomogeneity in climate series. We briefly introduce the results of applying two commonly accepted and well-developed methods (RHtest and MASH) to surface climate observations such as temperature and wind speed in China. We then summarize current progress and problems in this field, and propose ideas for future studies in China. Along with collecting more detailed metadata, more research on homogenization technology should be done in the future. On the basis of comparing and evaluating advantages and disadvantages of different homogenization methods, the homogenized climate data series of the last hundred years should be rebuilt.
文摘Cardiac resynchronization therapy (CRT) is associated with a favorable outcome only in patients with left bundle branch block (LBBB) pattern and in patients with a QRS duration 〉 150 ms, in patients with non-LBBB pattern with a QRS duration of 120-150 ms usually is not beneficial. After adjusting for QRS duration, QRS morphology was no longer a determinant of the clinical response to CRT. In contrast to the mainstream view, we hypothesized that the unfavorable CRT outcome in patients with non-LBBB and a QRS duration of 120-150 ms is not due to the QRS morphology itself, but to less dyssynchrony and unfavorable patient characteristics in this subgroup, such as more ischemic etiology and greater prevalence of male patients compared with patients with LBBB pattern. Further, the current CRT technique is devised to eliminate the dyssynchrony present in patients with LBBB pattern and inappropriate to eliminate the dyssynchrony in patients with non-LBBB pattern. We also hypothesized that electrocardiography may also provide information about the presence of interventricular and left intraventricular dyssynchrony and the approximate location of the latest activated left ventricular (LV) region. To this end, we devised new ECG criteria to estimate interventricular and LV intraventricular dyssynchrony and the approximate location of the latest activated LV region. Our preliminary data demonstrated that the latest activated LV region in patients with nonspecific intraventricular conduction disturbance (NICD) pattern might be at a remote site from that present in patients with LBBB pattern, which might necessitate the invention of a novel CRT technique for patients with NICD pattern. The application of the new interventricular and LV intraventricular dyssynchrony ECG criteria and a potential novel CRT technique might decrease the currently high nonresponder rate in patients with NICD pattern.
文摘The expression of mRNA for bone morphogenetic protein-1 (BMP-1) was investigated in fetal human cartilage and bone during the developing endochondral ossification by using in situ hybridization. BMP-1 mRNA was localized in the hypertrophic chondrocytes, the cells of perichondrium, osteoblasts and marrow cells. The results suggest that BMP-1 may involve in cartilage and bone formation, and in regulation of calcification of growth plate.As a comparative study, the expression of TGF-β1 protein was investigated in cartilage and bone using immunohistochemical staining, correlated expression of TGF-β1 and BMP-1 was found. The results suggest that BMP-1 and TGF-β1 act synergistically to influence endochrondral ossification.
基金National Natural Science Foundation of China under Grant Nos.70431002 and 10672093
文摘Synchronization in coupled oscillator networks has attracted much attention from many fields of science and engineering. In this paper, it is firstly proved that the oscifiator network with nonlinear coupling is also eventually dissipative under the hypothesis of eventual dissipation of the uncoupled oscillators. And the dynamics of the network is analyzed in its absorbing domain by combining two methods developed recently. Suufficient conditions for synchronization in the oscillator networks with nonlinear coupling are obtained. The two methods are combined effectively and the results embody the respective merits of the two methods. Numerical simulations confirm the validity of the results.
基金Project supported by the National Natural Science Foundation of China (No. 50277035)the Natural Science Foundation of Zheji-ang Province (No. Z104441),China
文摘Cascaded multilevel converters built with integrated modules have many advantages such as increased power density,flexible distributed control,multi-functionality,increased reliability and short design cycles.However,the system performance will be affected due to the synchronization errors among each integrated modules.This paper analyzes the impact of the three kinds of synchronization errors on the whole system performance,as well as detailed synchronization implementation.Some valuable conclusions are derived from the theoretical analysis,simulations and experimental results.