A mobile device and method in one example for automatically redialing a dialed number when a call has failed is provided. A releasable athletic shoe sole includes a detachable lower sole; a mechanical release mechanism constructed to release when a predetermined force is applied; and a longitudinal guiding element. The output video segments are combined into a video block for further distribution. When an impeller, mounted within the rearward chamber, rotates as a result of patient exhalation into the rearward chamber, the repulsive force between said magnets causes said piston to move and drive a bolus of air into the airway of the patient. In one embodiment, a dopant is introduced into the insulation structure with a concentration which on average increases or decreases in the vertical direction from a pre-processed semiconductor surface, the openings are formed in a dry-etching step and the aspect ratio of the openings is reduced by increasing the basic surface area of the openings using a subsequent wet-chemical etching step.