function loadAbstract(source){
   callAHAH(source,interpretAbstract,"GET");
}

function closeAbstract(){
   var abstract_overlay = document.getElementById("overlay_container");
   abstract_overlay.style.display = "none";	
}


function interpretAbstract(xmlDoc){
   var abstract   = xmlDoc.getElementsByTagName("abstract")[0].firstChild.data;

   var abstract_content = document.getElementById("overlay_content");
   abstract_content.innerHTML = abstract;
	
   var abstract_overlay = document.getElementById("overlay_container");
   abstract_overlay.style.display = "block";
}


function callAHAH(url, func, meth){
	try{
		if( window.ActiveXObject)
		{
			req = new ActiveXObject("Microsoft.XMLHTTP");
		}	
		else if( window.XMLHttpRequest)
		{
			req = new XMLHttpRequest();
		}
	}
	catch(e)
	{
      	alert("");
	}
	req.onreadystatechange = function()
	{
		responseAHAH(func);
	};
	
	try
	{
		req.open(meth,url,true);
      	req.setRequestHeader("content-type","application/x-www-form-urlencoded");
		req.send(null);
	}
	catch(e)
	{
      	req.load(url);
	}
}    


function responseAHAH(func)
{
	if(req.readyState == 4)
	{
		output = req.responseText;
		try
		{
			if( window.XMLHttpRequest )
			{
				xmlDoc = req.responseXML.documentElement;
			}
			else if( window.ActiveXObject )
			{
				xmlDoc = new ActiveXObject("Microsoft.XMLDOM");
				xmlDoc.loadXML(req.responseText);
			}
	    	func(xmlDoc,req);
       	}
		catch(e)
		{
			func(req,req);
       	}
	}
}