1. Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
2. Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
3. Department of Computational Biology and Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
4. The Nelson Mandela African Institute of Science and Technology, School of Life Sciences and Bioengineering, Arusha, Tanzania.
5. Institute of Nanoengineering and Microsystems, National Tsing Hua University, Hsinchu 300, Taiwan.
6. Nanotechnology Research Division, Centre for Mechanical Technology and Automation, Department of Mechanical Engineering, University of Aveiro, Portugal.
7. Deceased.
8. Departamento de Ingeniería Mecánica y Metalúrgica, Pontificia Universidad Católica Santiago de Chile, Avenida Vicuña Mackenna 4860, Macul, Santiago, Chile.
9. Centre for Biomolecular Engineering, Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, Queensland 4072, Australia.