A knock-out non-human animal, in particular a mouse, carrying a QPCTL knock-out mutation. The anti-friction bearing has an inner race and an outer race surrounding the inner race at a radial distance. The mounting tray includes a front panel secured to the front plate, and a side panel connected to the front panel. If gas pressure builds up in the cylinder against the stopper during limited gas flow into the cylinder, leakage from the cylinder is below the allowed maximum leakage. The second shockwave source device may be disposed at least partially in the aperture.