1. Cystic Fibrosis and Pulmonary Research and Treatment CenterSchool of MedicineUniversity of North Carolina at Chapel Hill Chapel Hill NC 27599 USA
2. Department of Mechanical Engineering and Materials ScienceEdmund T. Pratt Jr. School of EngineeringDuke University Durham NC 27708 USA
3. Faculty of Engineering ScienceUniversity of Bayreuth Universitätsstr. 30 95440 Bayreuth Germany
4. Bavarian Polymer Institute Universitätsstr. 30 95440 Bayreuth Germany