A gastroretentive composition comprises a mixture comprising an active ingredient component and an excipient component. Curved corners of the board are provided with diverging corrugations to prevent \u2018walking\u2019 of bottles from the corners of layers. Here, a resistance Rs of the resistive protection element has a value between a forward resistance Rf and a reverse resistance Rr of a current of the light emitter. An air turbine is mounted in the narrowest region of the venturi and is adapted to generate electricity.