An airbag retainer houses and holds an airbag and an inflator for supplying gas for inflating the airbag. The handles are coupled to a transmission so that movement of the handles by a user create rotational movement of a transmission input, movement of the handles in one direction creating rotational movement of the transmission input in one direction and movement of the handles in the opposite direction creating rotational movement of the transmission input in the opposite direction. Methods of removing contaminants from a membrane electrode assembly of a fuel cell and of improving performance of a fuel cell are also provided. A dependency registry stores a representation of each identified component that is configured for change notifications. The invention can achieve the result in a non-iterative direct way. Typically, the radial constraint of the outer radially constraining section is carried out by relative axial movement between the outer radially constraining section and the radially expandable shear barrier.