Funding for this research was provided by:
Key Technologies Research and Development Program (2016YFC0900100)
National Natural Science Foundation of China (81573022, 31530036, 91742203)
Text and Data Mining valid from 2018-12-01
First Online: 3 December 2018
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.