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.
Mitsubishi Electric Corporation has developed a wireless network system for surveillance cameras that uses multihop technology to enable users to set up a network simply by connecting the wireless cameras using visualization software, without any need for power cords or a wired LAN.