M.V. Voitikova – Ph.D. (Phys.-Math.), Leading Research Scientist, 

Institute of Physics, National Academy of Sciences (Minsk, Republic of Belarus) voitikova@imaph.bas-net.by, m.voitikova@dragon.bas-net.by

R.V. Khursa – Ph.D. (Med.), Department of Polyclinic Therapy, Belarusian State Medical University (Minsk) Rvkhursa@tut.by