Calciphylaxis. Calciphylaxis is a condition characterised by necrosis (cellular death) of the skin and fatty tissue. It is seen mainly in patients with end stage kidney disease. It is also sometimes called calcific uraemic arteriolopathy.
Besides a data link, USB provides 5 +/- 0.25 volts to power an otherwise unpowered device or charge a battery in a self powered device. A USB controller or hub is required to power one unit load (100 mA, a low power load). It can optionally power up to 5 unit loads (500 mA, a high power load).
Average Power Output. The average power of a USB port is about 5 volts. Your USB device will be able to draw out a maximum of 500 milliamperes (mA), but most default to 100 mA until prompted to provide more power by the device software. If your device requires more power than 500 mA, it may work slower or not at all while plugged into your computer.