The application of L-arginine and its derivatives to the skin causes beneficial effects of wound healing, increasing erectile function and increased growth of hair when applied in sufficient quantity to the skin. In one advantageous method in accordance with the present invention, a masking material comprising a substrate and an adhesive disposed over a first face of the substrate is provided. The scan line is positioned over the substrate and the gate dielectric layer is positioned over the substrate covering the scan line. The relative positions of the second and third linkage members, and as a result, the orientation of the steering column, is maintained by a releasable lock assembly extending through the end of said housing as well as the end portions of the second and third linkage members. The mounting mechanism for the scoop causes the scoop to assume a relatively vertical position during scooping, to minimize formation of a wave of litter in front of the scoop as it is rotated, but causes the scoop to assume a more horizontal position as the scoop is removed, so the collected waste will not spill from the scoop during removal.