function ChangeScreenshot(imageNodeId, imageDescription, imageUrl, imageNum) {
   var ssImage = Ext.get('ss-image');
   if (ssImage != null) {
      ssImage.dom.src = imageUrl;
   }
  var boxImage1 = Ext.get("id-1");
  if (boxImage1 != null) {
      boxImage1.dom.src = "/images/CaseStudy/btnunSelected.gif";
   }
  var boxImage2 = Ext.get("id-2");
  if (boxImage2 != null) {
      boxImage2.dom.src = "/images/CaseStudy/btnunSelected.gif";
   }
  var boxImage3 = Ext.get("id-3");
  if (boxImage3 != null) {
      boxImage3.dom.src = "/images/CaseStudy/btnunSelected.gif";
   }
  var boxImage4 = Ext.get("id-4");
  if (boxImage4 != null) {
      boxImage4.dom.src = "/images/CaseStudy/btnunSelected.gif";
   }
  var boxImage = Ext.get("id-" + imageNum);
  if (boxImage != null) {
      boxImage.dom.src = "/images/CaseStudy/btnSelected.gif";
   }
   var h4Description = Ext.get('landingLink');
   if (h4Description != null) {
     h4Description.dom.innerHTML = imageDescription;
   }
}