Some new nitrogen bridge-head pyrido[1,2-b][1,2,4]triazepines incorporating 6methylchromone moiety have been synthesized from the reaction of 1,6-diamino-4-(6methyl-4-oxo-4H-chromen-3-yl)-2-oxo-1,2-dihydropyridine-3,5-dicarbonitrile (4) with some α,γ-bifunctional electrophiles including 2-cyano-3,3-bis(methylthio)acrylonitrile, 2cyano-3,3-bis(methylthio)prop-2-enamide, 5-chloro-3-methyl-1-pheny...

This document contains requirements for an interoperable public safety broadband communications nationwide network to serve all local, tribal, state, and federal first responder communications.

Under certain circumstances, the collision of magnetic monopoles, topologically locked-in regions of false vacuum, leads to topological inflation and the creation of baby universes. The future evolution of initial data represented by the two incoming monopoles may contain a timelike singularity but this need not be the case. We discuss the global structure of the spacetime associated with monop...

A co-ordinated empirical European work (Project REPRESENTATION, MM 1045) has been led in six countries, with the aim of getting an insight of pupils’representations regarding ICT. A common protocol was defined. According to it, the pupils of one classroom in each country (fourth and fifth graders) were asked to draw a computer, to label its parts and to write short texts about computer uses. Re...