Abstract: The present invention relates to a compound of formula (I) or a pharmaceutically acceptable salt and/or solvate thereof, for use as a drug, especially as an antibiotic. The present invention also relates to a pharmaceutical composition comprising said compound of formula (I) and at least one pharmaceutically acceptable excipient. The present invention further concerns a method of preparation of a compound of formula (I?).

Abstract: Disclosed is an apparatus for storing electrical energy in a superconducting coil. The secondary phenomenon of magnetic induction which limits the size of existing superconducting energy storage coils is overcome by utilizing two superconductor material coils coupled by mutual induction through a high permeability magnetic material. This eliminates induction in the superconductor material thus eliminating the difficulty of the destruction of superconducting capability because of secondary induction. This construction permits high current storage capability in a small volume.

Abstract: Photovoltaic cell comprising two heterojunctions between three component semiconductors Ga.sub.1-x AL.sub.x As with x varying from 0 to 0.9, GaAs, and Ge which have respective bandgaps of 0.66, 1.43 and 2.4 eV, lattice constants matching at 0.07% and expansion coefficients matching at 1.7%. The cell is mounted in a cell device comprising a parallelepipedal unit, a Fresnel lens, a tapering cavity within said unit, partially filled up with a lens shaped antireflecting transparent material and a radiator, said device forming a sunlight concentrator.