The invention relates to a device comprising a multilayered structure with a first portion and a second portion wherein the first portion is conceived to be rolled about a first roller, said device comprising a second roller for receiving the second portion for at least partially counteracting the effects of mechanical strain induced in the multilayered structure upon said rolling. Each of the first and second hemispheric cups has two semi-conical engagement edges fittingly engaged with two semi-conical connection edges of the other hemispheric cup so as to integrally unite the first hemispheric cup and the second hemispheric cup together to form the ball cover. Where one element transmits signals at two different wavelengths, the apparatus may separate parts of the corresponding optical signal portion according to wavelength and process them separately. The compounds are useful as protein kinase inhibitors, especially as inhibitors of GSK-3, for treating diseases such as diabetes and Alzheimer’s disease. A single, liquid, non-cryogenic rocket fuel is standardized throughout the entire system which eliminates: all vertical launches; all expendables; all solid rocket propellants. Low cost self-cooling solid state light sources can integrate the electrical interconnect of the LEDs and other semiconductor devices.