function toggle( targetId ){
  if (document.getElementById){
        target = document.getElementById( targetId );
           if (target.style.display == "none"){
              target.style.display = "";
           } else {
              target.style.display = "none";
           }
     }
} 

var current_panel = 0;
var panels = 4;

function showLastPanel() {
	$('div#article_' + current_panel).hide();
	if (current_panel > 0) {
		current_panel--;
	} else {
		current_panel = panels;
	}
	$('div#article_' + current_panel).show();
}
function showNextPanel() {
	$('div#article_' + current_panel).hide();
	if (current_panel < panels) {
		current_panel++;
	} else {
		current_panel = 0;
	}
	$('div#article_' + current_panel).show();
}

function startPanel() {
	setInterval('showNextPanel()', 5000);
}