Funding for this research was provided by:
National Natural Science Foundation of China (81471781)
National Key Scientific Instrument and Equipment Development Projects of China (2012YQ160203)
Text and Data Mining valid from 2019-09-10
Received: 23 April 2019
Accepted: 19 August 2019
First Online: 10 September 2019
Ethics approval and consent to participate
: Does not apply as it is a review article.
: Not applicable.
: The authors declare that they have no competing interests.