Funding for this research was provided by:
Ministry of Education and Science of the Russian Federation (Agreement No 074-02-2018-328)
Text and Data Mining valid from 2018-10-26
Received: 6 August 2018
Revised: 11 October 2018
Accepted: 12 October 2018
First Online: 26 October 2018
Compliance with ethical standards
: The authors declare that they have no conflict of interest.
: This article does not contain any studies with human participants or animals, performed by any of the authors.