1. School of Public Health, Faculty of Health Sciences, Curtin University; GPO Box U1987 Perth WA 6845 Australia
2. Fluid Dynamics Research Group, Curtin University; GPO Box U1987 Perth WA 6845 Australia
3. Institute for Mechanical Process Engineering and Mechanics (MVM), Karlsruhe Institute of Technology; D-76131 Karlsruhe Germany
4. Rhodius GmbH; D-91781 Weißenburg Germany