Department of Mathematical Sciences and Technology, Norwegian University of Life Sciences, xc3x85s, Norway. s.leski@nencki.gov.pl|Department of Mathematical Sciences and Technology, Norwegian University of Life Sciences, xc3x85s, Norway. s.leski@nencki.gov.pl|Department of Mathematical Sciences and Technology, Norwegian University of Life Sciences, xc3x85s, Norway. s.leski@nencki.gov.pl|Department of Mathematical Sciences and Technology, Norwegian University of Life Sciences, xc3x85s, Norway. s.leski@nencki.gov.pl|Department of Mathematical Sciences and Technology, Norwegian University of Life Sciences, xc3x85s, Norway. s.leski@nencki.gov.pl