$parent_item = (($item['thr-parent']) ? $item['thr-parent'] : $item['parent-uri']);
xml::add_element($doc, $as_object, "activity:object-type", self::construct_objecttype($parent[0]));
$parent_item = (($item['thr-parent']) ? $item['thr-parent'] : $item['parent-uri']);
xml::add_element($doc, $as_object, "activity:object-type", self::construct_objecttype($parent[0]));