Global Navigation add class based on selected node sub node.

 $('.ms-core-listMenu-root > li > ul').find('li.dynamic >a[href^="/' + location.pathname.split("/")[1] + '"]').closest('li.dynamic-children').addClass('DefaultSelected');

Sharepoint 2013 show PDF document in flyoutmenu
http://www.wictorwilen.se/sharepoint-2013-enabling-pdf-previews-with-office-web-apps-2013-march-2013-update