The only way to do this is using the tiny power button on the top of the unit, right next to the volume button. (lightgungalaxy.com)
The Pure has stereo speakers on either side of the tablet, with a front - facing camera and power button on the top of the slate. (laptopmag.com)
There is a a lock / power button on the top right next to the micro-USB port and microphone, and a volume rocker on the top left next to the headphone jack. (goodereader.com)