A plurality of devices and a device system are disclosed, in which a plurality of input devices generate an input AV signal, a related device records and reproduces the AV signal, and a display device displays the AV signal. The tooth cleaning elements include cleaning elements that define a loop arrangement for better retention of the dentifrice, a central cleaning element disposed within the loop, two opposing arcuate cleaning elements disposed on opposite sides of the loop, peripheral cleaning element with a stepped and tapered construction, elongate distal cleaning elements, and proximal cleaning elements. The apparatus can also include a ramp in front of the suspension components, aerodynamically shaped wings on the axles, and a rear diffuser, such components configured to direct air smoothly between the trailer suspension and the ground. A therapeutic agent is eluted from the implant into at least one of the anterior chamber, a physiologic outflow pathway of the eye, and a space adjacent a choroid of the eye. Parallel query plans can then be generated from the annotated SQL server MEMO in a bottom up manner from leaf operators to a root operator.