Institute of Physical Biology, University of South Bohemia, Academic and University Centre, Zámek 136, 373 33 Nové Hrady, Czech Republic. levitner@ufb.jcu.cz|Institute of Physical Biology, University of South Bohemia, Academic and University Centre, Zámek 136, 373 33 Nové Hrady, Czech Republic. levitner@ufb.jcu.cz|Institute of Physical Biology, University of South Bohemia, Academic and University Centre, Zámek 136, 373 33 Nové Hrady, Czech Republic. levitner@ufb.jcu.cz