Strelcov, Evgheni
Kumar, Rajeev
Bocharova, Vera
Sumpter, Bobby G.
Tselev, Alexander
Kalinin, Sergei V.
Article History
Received: 2 September 2014
Accepted: 31 December 2014
First Online: 27 January 2015
Competing interests
: The authors declare no competing financial interests.