A device having an optically active region includes a silicon substrate and a SiGe cladding layer epitaxially grown on the silicon substrate. An iso-stress element is laminated to the sail body material to create an iso-stress portion at a corner of the sail body. The new resins were characterized by useful properties in impact, tear, adhesion, sealing, extruder motor loads and pressures at comparable melt index values, and neck-in and draw-down. The AGV moves on the guidance path and is guided by the guidance path. Before the media file is imported from the external device, the method uses the media clip data structure to edit a composite presentation with the media file. A plurality of these arrangements can be provided across the cleaning head, and a part of the agitation apparatus, such as the driver, can be mounted on the main body of the vacuum cleaner.