Methods and systems for rapid creation of copies of a mapped storage volume. The data symbols and pilot symbols are transmitted in frequency subcarriers and timeslots, whereby pilot symbols are transmitted in a continuous stream within at least one frequency subcarrier. This arrangement enables the cavities to be fed with lead at approximately the same time and hence the dip of the lugs into the cavities can be optimised without any significant difficulties. The phase-change recording material, a method of producing the optical recording medium, and a method of writing information in the optical recording medium, reading written information therefrom and rewriting written information therein are proposed. When the electric fields are selected to produce oscillating trajectories having the same as a multiple of the frequency of the emitted x-rays, the resulting photons can be made to constructively interfere with each other to produce a coherent x-ray source. Additionally, the present application describes pharmaceutical compositions comprising at least one compound according to Formula I and optionally one or more additional therapeutic agents.