function showDesc(descText,image,map_name) {
  document.getElementById('regions_desc').firstChild.nodeValue=descText;
  document.getElementById(map_name).src=image;
}

function hideDesc(image,map_name) {
  document.getElementById('regions_desc').firstChild.nodeValue="\u00a0";
  document.getElementById(map_name).src=image;
}