In the practical problems such as nuclear waste pollution and seawater intrusion etc., many problems are reduced to solving the convection-diffusion equation, so the research of convection-diffusion equation is of gre...In the practical problems such as nuclear waste pollution and seawater intrusion etc., many problems are reduced to solving the convection-diffusion equation, so the research of convection-diffusion equation is of great value. In this work, a spectral method is presented for solving one and two dimensional convection-diffusion equation with source term. The finite difference method is also used to solve the convection diffusion equation. The numerical experiments show that the spectral method is more efficient than other methods for solving the convection-diffusion equation.展开更多
The wavelength shift in fiber Bragg grating does not depend directly on the total light levels, losses in the connecting fibers and couplers, or source power. However, if the tunable Fabry-Perot filter is place on the...The wavelength shift in fiber Bragg grating does not depend directly on the total light levels, losses in the connecting fibers and couplers, or source power. However, if the tunable Fabry-Perot filter is place on the end of incident fiber, the detected time delay of modulation light is occurred due to the unmatch between the scanning time and light transmission time in the transmission fiber. Consequently, the detected peak wavelength shifts with the length of transmission fiber. Thus, the peak wavelength shift effect of Bragg reflective light transmitted in fiber with different fiber length can be obvious in the demodulator with a prepositive tunable Fabry-Perot filter. The experiment indicates the shift rates of 0.109 - 0.126 nm/km increase approximately linearly with the original peak wavelength of 1532.917 - 1560.300 nm at the fiber length of 0 - 6 km. To certify the consistency of measurement data, the criterion correction is introduced. By using the differential method of two fiber Bragg gratings with an optical path, the differential worth is compensated from the disturbance modulated by the time delay of fiber length.展开更多
Left sided valvular heart disease poses major impact on life and lifestyle.Medical therapy merely palliates chronic severe valve disease and once symptoms or haemodynamic sequelae appear,life expectancy is markedly tr...Left sided valvular heart disease poses major impact on life and lifestyle.Medical therapy merely palliates chronic severe valve disease and once symptoms or haemodynamic sequelae appear,life expectancy is markedly truncated.In this article,we review the mechanisms of valve pathology,latest evidence in the quest for pharmacological options,means by which to predict deterioration,and standard and novel treatment options.展开更多
To the Editor:Transcatheter aortic valve replacement(TAVR)has become an established treatment for patients with severe aortic stenosis(AS)at all levels of surgical risk.^([1,2])With the exploration of TAVR and technol...To the Editor:Transcatheter aortic valve replacement(TAVR)has become an established treatment for patients with severe aortic stenosis(AS)at all levels of surgical risk.^([1,2])With the exploration of TAVR and technological developments,TAVR is an alternative for patients with intermediate or low surgical risk.^([3])There are some studies regarding gender differences in TAVR,but there are few studies on it in Asia.^([4])However,the studies of outcomes based on gender differences in TVAR are still lacking,especially in China and other Asian countries.展开更多
文摘In the practical problems such as nuclear waste pollution and seawater intrusion etc., many problems are reduced to solving the convection-diffusion equation, so the research of convection-diffusion equation is of great value. In this work, a spectral method is presented for solving one and two dimensional convection-diffusion equation with source term. The finite difference method is also used to solve the convection diffusion equation. The numerical experiments show that the spectral method is more efficient than other methods for solving the convection-diffusion equation.
文摘The wavelength shift in fiber Bragg grating does not depend directly on the total light levels, losses in the connecting fibers and couplers, or source power. However, if the tunable Fabry-Perot filter is place on the end of incident fiber, the detected time delay of modulation light is occurred due to the unmatch between the scanning time and light transmission time in the transmission fiber. Consequently, the detected peak wavelength shifts with the length of transmission fiber. Thus, the peak wavelength shift effect of Bragg reflective light transmitted in fiber with different fiber length can be obvious in the demodulator with a prepositive tunable Fabry-Perot filter. The experiment indicates the shift rates of 0.109 - 0.126 nm/km increase approximately linearly with the original peak wavelength of 1532.917 - 1560.300 nm at the fiber length of 0 - 6 km. To certify the consistency of measurement data, the criterion correction is introduced. By using the differential method of two fiber Bragg gratings with an optical path, the differential worth is compensated from the disturbance modulated by the time delay of fiber length.
文摘Left sided valvular heart disease poses major impact on life and lifestyle.Medical therapy merely palliates chronic severe valve disease and once symptoms or haemodynamic sequelae appear,life expectancy is markedly truncated.In this article,we review the mechanisms of valve pathology,latest evidence in the quest for pharmacological options,means by which to predict deterioration,and standard and novel treatment options.
基金supported by grants from the West China Hospital“1·3·5”Discipline of Excellence Project-“Mechanisms of aortic stenosis and the clinical applications”,National Natural Science Foundation of China(No.82001899)the National Natural Science Foundation of China(No.81901825).
文摘To the Editor:Transcatheter aortic valve replacement(TAVR)has become an established treatment for patients with severe aortic stenosis(AS)at all levels of surgical risk.^([1,2])With the exploration of TAVR and technological developments,TAVR is an alternative for patients with intermediate or low surgical risk.^([3])There are some studies regarding gender differences in TAVR,but there are few studies on it in Asia.^([4])However,the studies of outcomes based on gender differences in TVAR are still lacking,especially in China and other Asian countries.
