Expire is not really the right term; but effectively yes. In general a cheque older than six months will be considered stale-dated and will not be honoured. Reference the Canadian Payments Association FAQ.
SKYACTIV is a brand name for a series of technologies developed by Mazda which increase fuel efficiency and engine output. The initial announcement of the SKYACTIV technologies include new engines, transmissions, body, and chassis, which appeared in Mazda products from 2011.
Hp Accelerometer System Tray is a part of the HP 3D DriveGuard application from Hewlett-Packard company. HP 3D DriveGuard protects the hard drive (HDD) by parking the heads if the notebook is accidentally dropped or is abruptly impacted by another object. More info on http://welcome.hp.com.