Funding for this research was provided by:
Russian Foundation for Basic Research (15-04-05579)
Text and Data Mining valid from 2019-02-06
Received: 24 March 2018
Accepted: 25 January 2019
First Online: 6 February 2019
Compliance with Ethical Standards
: On behalf of all authors, the corresponding author states that there is no conflict of interest.
: This article does not contain any studies with human participants or animals performed by any of the authors.