function window_open(psURL,psName,pnWidth,pnHeight,pnTop,pnLeft,pbScroll){
	var nLeft=pnLeft || Math.round((window.screen.width-pnWidth)/2);
	var nTop=pnTop || Math.round((window.screen.height-pnHeight)/2)-20;	
	if (psName=="") psName=null;
	var oWindow=window.open(psURL,psName,"top="+nTop+",left="+nLeft+",height="+pnHeight+",width="+pnWidth+",status=no,toolbar=no,menubar=yes,location=no,resizable=no"+((pbScroll)?",scrollbars=yes":""));
	oWindow.focus();
}
function js_trim(ps_cadena){
//Quita los espacios al inicio y al final de una cadena (ps_cadena)
	return(ps_cadena.replace(/(^\s+)|(\s+$)/g,""));
}
function ns_reload(){
	document.location.href=document.location.href
}