Funding for this research was provided by:
National Science Foundation (AGS-1408897, AGS-1408897)
Russian Science Foundation (18-12-00231)
Ministry of Education and Science of the Russian Federation (14.W03.31.0006)
Article History
Received: 21 May 2018
Revised: 20 August 2018
Accepted: 23 August 2018
First Online: 20 November 2018
Competing interests
: The authors declare no competing interests.