Funding for this research was provided by:
National Natural Science Foundation of China (81803334)
National Centre for Global Health and Medicine (30A-1007)
Text and Data Mining valid from 2018-11-28
Received: 13 July 2018
Accepted: 15 November 2018
First Online: 28 November 2018
Ethics approval and consent to participate
: Not applicable, as this was a mathematical model.
: Not applicable.
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