Affiliation: | 1. Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455‐0132;2. telephone: 612‐626‐7630;3. fax: 612‐626‐7246;4. Stem Cell Institute, University of Minnesota, Minneapolis, Minnesota;5. Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota;6. Interdepartmental Stem Cell Institute Leuven, Catholic University Leuven, Leuven, Belgium |