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J. 568,L75–L79(2002).Acknowledgements The VLA is operated by the National Radio Astronomy Observatory(NRAO), a facility of the National Science Foundation (NSF), operated under co-operativeagreement by Associated Universities, Inc. (AUI). This work is based partly on observationscarried out with the IRAM Plateau de Bure Interferometer. IRAM is supported by INSU/CNRS(France), MPG (Germany) and IGN (Spain). F.W. is a Jansky Fellow.Competing interests statement The authors declare that they have no competing financialinterests.Correspondence and requests for materials should be addressed to F.W. ([email protected])...............................................................Rotational actuators basedon carbon nanotubesA. M. Fennimore*, T. D. Yuzvinsky*, Wei-Qiang Han*, M. S. Fuhrer*†,J. Cumings*† & A. Zettl** Department of Physics, University of California at Berkeley, and MaterialsSciences Division, Lawrence Berkeley National Laboratory, Berkeley, California94720, USA.............................................................................................................................................................................Nanostructures are of great interest not only for their basicscientific richness, but also because they have the potentialto revolutionize critical technologies. The miniaturization ofelectronic devices over the past century has profoundly affectedhuman communication, computation, manufacturing and trans-portation systems. True molecular-scale electronic devices arenow emerging that set the stage for future integrated nanoelec-tronics1. Recently, there have been dramatic parallel advances inthe