Let X be a graph, with corresponding simply-laced Coxeter group W . Then W acts naturally on the lattice L spanned by the vertices of X, preserving a quadratic form. We give conditions on X for the form to be nonsingular modulo two, and study the images of W −→ O(L/2kL). Introduction — This paper investigates the tower of 2-power congruence subgroups in a simply-laced Coxeter group, but the sto...

BRAINSTORMS is a monthly section of The Journal of Clinical Psychiatry aimed at providing updates of novel concepts emerging from the neurosciences that have relevance to the practicing psychiatrist. From the Clinical Neuroscience Research Center in San Diego and the Department of Psychiatry at the University of California San Diego. Reprint requests to: Stephen M. Stahl, M.D., Ph.D., Editor, B...

Greenstone and DSpace are widely used software systems for digital libraries, and prospective users sometimes wonder which one to adopt. In fact, the aims of the two are very different, although their domains of application do overlap. This article describes the two systems and identifies their similarities and differences. We also present StoneD [note 1] a bridge between the production version...

At an initial step during synaptic vesicle recycling, dynamin and adaptor proteins mediate the endocytosis of synaptic vesicle components from the plasma membrane. StonedA and stonedB, novel synaptic proteins encoded by a single Drosophila gene, have predicted structural similarities to adaptors and other proteins implicated in endocytosis. Here, we test possible roles of the stoned proteins in...