A hydrogen source comprises a first hydrogen reservoir for containing hydrogen in a first form and a second hydrogen reservoir for containing hydrogen in a second form different from the first form. The dielectric material layer has a micro-tubular shape, and a light emitting layer is filled in the dielectric material layer. The general purpose engine enumerates the properties in response to a query in a design-time environment. The electrosurgical systems include at least one structure andor operational characteristic for enhancing ultrasonic visibility of the energy-delivery devices within tissue during ultrasonography. The vacuum source is spaced apart from the receptacle, is connected to the receptacle, and is effective to provide a vacuum in the receptacle and in the space. The inductive image-generation process is recursive in that in case it is necessary to assemble supplier tiles in the course of the inductive image-generation process then they too are assembled by the process of inductive image generation.