Bioengineering Department, University of California San Diego, La Jolla, California, USA.|Bioengineering Department, University of California San Diego, La Jolla, California, USA.|Bioengineering Department, University of California San Diego, La Jolla, California, USA.|Bioengineering Department, University of California San Diego, La Jolla, California, USA.|Bioengineering Department, University of California San Diego, La Jolla, California, USA.