function scrollDownTopics() {
  var anim = new YAHOO.util.Scroll(
  document.getElementById('topicsdetail'),
  { scroll: { by: [0, 280] } },
  0.5,
  YAHOO.util.Easing.easeOut
 );
 anim.animate();
}
function scrollUpTopics() {
  var anim = new YAHOO.util.Scroll(
  document.getElementById('topicsdetail'),
  { scroll: { by: [0, -280] } },
  0.5,
  YAHOO.util.Easing.easeOut
 );
 anim.animate();
}
function jumpPageTop() {
 var anim = new YAHOO.util.Scroll(
  document.getElementsByTagName('html')[0],
  { scroll: { to: [0, 0] } },
  0.5,
  YAHOO.util.Easing.easeOut
 );
 anim.animate();
}