DEAR EDITOR,Since our first identification of plasmid-mediated colistin resistance gene mcr-1 in 2015 （Liu et al., 2016）, it has been described in human clinics, domestic animals, foods, and the environment worldwi...DEAR EDITOR,Since our first identification of plasmid-mediated colistin resistance gene mcr-1 in 2015 （Liu et al., 2016）, it has been described in human clinics, domestic animals, foods, and the environment worldwide （Schwarz ＆ Johnson, 2016）. Although it is still rare, the emergence of mcr-I in wild animals is of great concern. We summarized two previous reports on mcr-1 in wild birds from Lithuania and Argentina to describe its emergence and characteristics in wildlife and highlight the potentially important role of wild animals, particularly birds, in its global transmission （Wang et al., 2017）. The first detection of mcr-1 in wildlife in Asia was identified in an extended-spectrum β- lactamase-producing Escherichia coil strain isolated from Eurasian coot （Fulica atra）,展开更多
DEAR EDITOR, We read with interest the article by Wang and colleagues regarding the role of wildlife in the transmission of antimicrobial resistance （AMR） （Wang et al., 2017）. Although we appreciate the efforts in...DEAR EDITOR, We read with interest the article by Wang and colleagues regarding the role of wildlife in the transmission of antimicrobial resistance （AMR） （Wang et al., 2017）. Although we appreciate the efforts in reviewing this important topic, we would like to comment on some statements that we believe are not up-to- date or properly cited.展开更多
A theoretical model of a nonlinear hyperbolic metamaterial is presented in the form of a stack of subwavelength layers of linear plasmonic and nonlinear dielectric materials. A broad picture of the properties of evane...A theoretical model of a nonlinear hyperbolic metamaterial is presented in the form of a stack of subwavelength layers of linear plasmonic and nonlinear dielectric materials. A broad picture of the properties of evanescent waves （high-k modes） in this stack is investigated by plotting global transmission diagrams. The presence of nonlinearity strongly modifies these diagrams. The emergence and modification of nonlinear evanescent waves is observed. Some signatures of nonlinear phenomenon such as formation of orbits and trajectories around fixed points are also seen in our work.展开更多
A robust SEIR epidemic disease model with a profitless delay and vertical transmission is formulated, and the dynamics behaviors of the model under pulse vaccination are analyzed. By use of the discrete dynamical syst...A robust SEIR epidemic disease model with a profitless delay and vertical transmission is formulated, and the dynamics behaviors of the model under pulse vaccination are analyzed. By use of the discrete dynamical system determined by the stroboscopic map, an ‘infection-free＇ periodic solution is obtained, further, it is shown that the ‘infection-free＇ periodic solution is globally attractive when some parameters of the model are under appropriate conditions. Using the theory on delay functional and impulsive differential equation, the sufficient condition with time delay for the permanence of the system is obtained, and it is proved that time delays, pulse vaccination and vertical transmission can bring obvious effects on the dynamics behaviors of the model. The results indicate that the delay is ‘profitless’.展开更多
Super High Definition (SHD) movies were successfully transmitted as streaming contents at about 300 Mbps for the first time over a long distance IP network (more than 3,000 km), in conjunction with the experimental ve...Super High Definition (SHD) movies were successfully transmitted as streaming contents at about 300 Mbps for the first time over a long distance IP network (more than 3,000 km), in conjunction with the experimental verification of traffic control and scalable multicast technologies.展开更多
基金partially supported by grants from the National Key Basic Research Program of China(2013CB127200)the National Natural Science Foundation of China(81661138002)
文摘DEAR EDITOR,Since our first identification of plasmid-mediated colistin resistance gene mcr-1 in 2015 （Liu et al., 2016）, it has been described in human clinics, domestic animals, foods, and the environment worldwide （Schwarz ＆ Johnson, 2016）. Although it is still rare, the emergence of mcr-I in wild animals is of great concern. We summarized two previous reports on mcr-1 in wild birds from Lithuania and Argentina to describe its emergence and characteristics in wildlife and highlight the potentially important role of wild animals, particularly birds, in its global transmission （Wang et al., 2017）. The first detection of mcr-1 in wildlife in Asia was identified in an extended-spectrum β- lactamase-producing Escherichia coil strain isolated from Eurasian coot （Fulica atra）,
文摘DEAR EDITOR, We read with interest the article by Wang and colleagues regarding the role of wildlife in the transmission of antimicrobial resistance （AMR） （Wang et al., 2017）. Although we appreciate the efforts in reviewing this important topic, we would like to comment on some statements that we believe are not up-to- date or properly cited.
文摘A theoretical model of a nonlinear hyperbolic metamaterial is presented in the form of a stack of subwavelength layers of linear plasmonic and nonlinear dielectric materials. A broad picture of the properties of evanescent waves （high-k modes） in this stack is investigated by plotting global transmission diagrams. The presence of nonlinearity strongly modifies these diagrams. The emergence and modification of nonlinear evanescent waves is observed. Some signatures of nonlinear phenomenon such as formation of orbits and trajectories around fixed points are also seen in our work.
基金the National Natural Science Foundation of China(No.10471117)
文摘A robust SEIR epidemic disease model with a profitless delay and vertical transmission is formulated, and the dynamics behaviors of the model under pulse vaccination are analyzed. By use of the discrete dynamical system determined by the stroboscopic map, an ‘infection-free＇ periodic solution is obtained, further, it is shown that the ‘infection-free＇ periodic solution is globally attractive when some parameters of the model are under appropriate conditions. Using the theory on delay functional and impulsive differential equation, the sufficient condition with time delay for the permanence of the system is obtained, and it is proved that time delays, pulse vaccination and vertical transmission can bring obvious effects on the dynamics behaviors of the model. The results indicate that the delay is ‘profitless’.
文摘Super High Definition (SHD) movies were successfully transmitted as streaming contents at about 300 Mbps for the first time over a long distance IP network (more than 3,000 km), in conjunction with the experimental verification of traffic control and scalable multicast technologies.
