window.onload=function(){
    styleNavigation();
}

var timeout	= 500;
var closetimer	= 0;
var ddmenuitem	= 0;

// style the navigation menu
function styleNavigation() {	
    var researchMenu = document.getElementById('researchMenu');
    var links = researchMenu.getElementsByTagName('li');
    var numLinks = links.length;
    links[0].className = 'firstLink';
    links[numLinks-1].className = 'lastLink';
}

// show navigation menu
function showNav(id) {	
	// cancel close timer
	cancelCloseTimer();

	// close old layer
	if(ddmenuitem) {
        ddmenuitem.style.visibility = 'hidden';
    }

	// get new layer and show it
	ddmenuitem = document.getElementById(id);
	ddmenuitem.style.visibility = 'visible';

}
// hide navigation menu
function hideNav() {
	if(ddmenuitem) {
        ddmenuitem.style.visibility = 'hidden';
    }
}

// close timer
function closeTimer() {
	closetimer = window.setTimeout(hideNav, timeout);
}

// cancel close timer
function cancelCloseTimer() {
	if (closetimer) {
		window.clearTimeout(closetimer);
		closetimer = null;
	}
}
// close layer when click-out
document.onclick = hideNav; 
function showAbstract(obj) {
    obj.style.display = 'none';
    obj.nextSibling.nextSibling.style.display = 'block';
    var btnHolder = obj.parentNode;
    // IE
    if (btnHolder.nextSibling.style != null) {
        btnHolder.nextSibling.style.display = 'block';
    }
    else {
        btnHolder.nextSibling.nextSibling.style.display = 'block';
    }
    return true;
}   
function hideAbstract(obj) {
    obj.style.display = 'none';
    obj.previousSibling.previousSibling.style.display = 'block';
    var btnHolder = obj.parentNode;
    // IE
    if (btnHolder.nextSibling.style != null) {
        btnHolder.nextSibling.style.display = 'none';
    }
    else {
        btnHolder.nextSibling.nextSibling.style.display = 'none';
    }
    return true;
}   
function showDescription(obj) {
    obj.style.display = 'none';
    obj.nextSibling.nextSibling.style.display = 'block';
    var btnHolder = obj.parentNode;
    // IE
    if (btnHolder.nextSibling.style != null) {
        btnHolder.nextSibling.nextSibling.style.display = 'block';
    }
    else {
        btnHolder.nextSibling.nextSibling.nextSibling.nextSibling.style.display = 'block';
    }
    return true;
}   
function hideDescription(obj) {
    obj.style.display = 'none';
    obj.previousSibling.previousSibling.style.display = 'block';
    var btnHolder = obj.parentNode;
    // IE
    if (btnHolder.nextSibling.style != null) {
        btnHolder.nextSibling.nextSibling.style.display = 'none';
    }
    else {
        btnHolder.nextSibling.nextSibling.nextSibling.nextSibling.style.display = 'none';
    }
    return true;
}