function WindowPopus(ruta,ancho,alto,valscroll)
{
var px,py;
	px=Math.round(screen.width/2) - Math.round(ancho/2) - 300
	py=(Math.round(screen.height/2) - Math.round(alto/2))-20
	window.open(ruta,"","toolbar=no,titlebar=no,width="+ancho+",height="+alto+",directories=no,status=yes,scrollbars="+valscroll+",resizable=no,resize=no,menubar=no,left="+px+",top="+py)
}