Sladkova, E. A.
Article History
Received: 18 November 2019
Revised: 20 April 2020
Accepted: 22 May 2020
First Online: 10 December 2020
COMPLIANCE WITH ETHICAL STANDARDS
: <i>Conflict of interests.</i> The authors declare that they have no conflict of interest.
: <i>Statement on the welfare of animals:</i> All manipulations with humans met the ethical standards of the Declaration of Helsinki, 1964, with later amendments. Informed consent was obtained from each participant of the study.