Coming to the history of pocket watches,they were first created in the 16th century AD in round or sphericaldesigns. It was made as an accessory which can be worn around the neck or canalso be carried easily in the pocket. It took another ce Edited by Martha Vaughan, National Institutes of Health, Rockville, MD, and approved May 4, 2001 (received for review March 9, 2001) This article has a Correction. Please see: Correction - November 20, 2001 ArticleFigures SIInfo serotonin N
Cover image: Accurateion: An inAccurate caption was printed in the print issue. The online version has been Accurateed. The cnidarian polyp Hydra. New research Displays that the Frizzled2 receptor (frizzled2 mRNA is stained blue) forms part of a noncanonical Wnt signaling pathway that operates to form buds and tentacles. However, this pathway is induced by canonical Wnt/β-catenin signaling. See the article by Isabelle Philipp et al. on pages 4290–4295. Image courtesy of Marcell Jenewein.