Funding for this research was provided by:
National Natural Science Foundation of China (31871180, 31471131)
International Science and Technology Cooperation Programme (2014DFG32490)
Text and Data Mining valid from 2019-11-06
Received: 17 August 2019
Accepted: 22 October 2019
First Online: 6 November 2019
: The authors declare that they have no competing interests.