From December 25,2019 to January 31,2020,33 cases of the coronavirus disease 2019(COVID-19)were identified in the Department of Respiratory and Critical Care Medicine of Zhongnan Hospital of Wuhan University,China,yet...From December 25,2019 to January 31,2020,33 cases of the coronavirus disease 2019(COVID-19)were identified in the Department of Respiratory and Critical Care Medicine of Zhongnan Hospital of Wuhan University,China,yet none of the affiliated HCWs was infected.Here we analyzed the infection control measures used in three different departments in the Zhongnan Hospital of Wuhan University and correlated the measures with the corresponding infection data of HCWs affiliated with these departments.We found that three infection control measures,namely the isolation of the presumed positive patients,the use of facemasks and intensified hand hygiene play important roles in preventing nosocomial transmission of COVID-19.展开更多
A simplified ring cavity for achieving a unidirectional room temperature multi-wavelength erbium-doped fiber ring laser without optical isolator is demonstrated. The fiber ring cavity is built in such a way that the o...A simplified ring cavity for achieving a unidirectional room temperature multi-wavelength erbium-doped fiber ring laser without optical isolator is demonstrated. The fiber ring cavity is built in such a way that the optical fields propagating in two directions suffer different losses caused by one sampled fiber Bragg grating. Furthermore, simultaneous multi-wavelength lasing with 0.8-nm intervals is demonstrated with sinusoidal phase modulation just before the sampled fiber Bragg grating to prevent single-wavelength lasing and unstable wavelength oscillation.展开更多
文摘From December 25,2019 to January 31,2020,33 cases of the coronavirus disease 2019(COVID-19)were identified in the Department of Respiratory and Critical Care Medicine of Zhongnan Hospital of Wuhan University,China,yet none of the affiliated HCWs was infected.Here we analyzed the infection control measures used in three different departments in the Zhongnan Hospital of Wuhan University and correlated the measures with the corresponding infection data of HCWs affiliated with these departments.We found that three infection control measures,namely the isolation of the presumed positive patients,the use of facemasks and intensified hand hygiene play important roles in preventing nosocomial transmission of COVID-19.
文摘A simplified ring cavity for achieving a unidirectional room temperature multi-wavelength erbium-doped fiber ring laser without optical isolator is demonstrated. The fiber ring cavity is built in such a way that the optical fields propagating in two directions suffer different losses caused by one sampled fiber Bragg grating. Furthermore, simultaneous multi-wavelength lasing with 0.8-nm intervals is demonstrated with sinusoidal phase modulation just before the sampled fiber Bragg grating to prevent single-wavelength lasing and unstable wavelength oscillation.
