1. Materials Research Department, iThemba LABS, National Research Foundation, P.O. Box 722, Somerset West 7129, South Africa
2. Department of Molecular Biology and Genetics, University of Aarhus, Gustav Wieds Vej 10 C, Aarhus C 8000, Denmark
3. Department of Animal Physiology and Ecotoxicology, University of Silesia, Bankowa 9, Katowice 40-007, Poland
4. AGH University of Science and Technology, Faculty of Physics & Applied Computer Science, al. A. Mickiewicza 30, Kraków 30-059, Poland