Abstract: An internal combustion barrel engine having rotating cylinders and pistons which together form combustion spaces. The combustion spaces are maintained at a substantially constant volume while a compressed air-fuel mixture is combusted therein.

Abstract: Devices and methods are provided for electrically stimulating a predetermined body part of a mammal. The method includes placing at least one electrode in proximity to the mammal's skin, injecting an electrically conductive gel into the body of the mammal so as to form a conductive gel pathway extending at least partially along a distance between the at least one electrode and the predetermined body part, and stimulating the predetermined body part by applying an electrical signal via the electrode that travels, at least in part, through the conductive gel pathway.