Contents

24 November 2000
Vol 290, Issue 5496

About The Cover

Cover image expansion

COVER A microfabricated cell sorter, with integrated pumps and valves and channel sizes on the order of 30 mm, was made by molding polydimethylsiloxane. This silicone elastomer is much softer than silicon and allows for low-force pneumatic actuation of the valves. Soft materials and nontraditional fabrication techniques such as molding are promising routes to practical nanomechanical devices, one of the topics of this special issue on nanotechnology, which starts on page 1523. [Photo: Felice Frankel]