1. Physics
of Fluids Group, MESA+ Institute for Nanotechnology, and MIRA Institute
for Biomedical Technology and Technical Medicine, University of Twente, P. O. Box 217, 7500 AE Enschede, The Netherlands
2. Department
of Biomedical Engineering, Thoraxcenter, Erasmus MC, Wyternaweg
80 EE 2302, 3015 CN Rotterdam, The Netherlands
3. Department
of Mechanical Engineering, University of Colorado, 1111 Engineering
Drive, Boulder, Colorado 80309-0427, United States