//Abre pop_up

function abre_pop(theURL,winName,W,H) {
	var X = Math.ceil( (window.screen.height - H) / 2 );
	var Y = Math.ceil( (window.screen.width - W) / 2 );
	window.open(theURL,winName,'width='+W+',height='+H+',top='+X+',left='+Y+',location=no,status=no,menubar=no,scrollbars=auto,resizable=no,directories=no,toolbar=no');
}