Comment by cypherpunks01

  function hide(id) {
    var el = document.getElementById(id);
    if (el) { el.style.visibility = 'hidden'; }
  }
  function vote(node) {
    var v = node.id.split(/_/);
    var item = v[1];
    hide('up_'   + item);
    hide('down_' + item);
    var ping = new Image();
    ping.src = node.href;
    return false;
  }