Abstract: This invention relates to a device and a method for positioning a sample (8) mounted on a glow discharge spectrometer (6). A sample (8) to be analyzed is mounted on the first electrode means (5) of a glow discharge spectrometer (6) then a detachable arm (11) is mounted on a mechanic assembly comprising a cutting tool (2). This detachable arm (11) comprises a light source (14) used for illuminating said sample (8) with a light beam having a diameter equal to the inner diameter of the first electrode means (5) and then the position of the light beam is located on the sample (8). The portion of the sample (8) which will be exposed effectively to the glow discharge may thus be located with accuracy.

Abstract: This invention relates to an optic multiplexer or demultiplexer comprising an inlet optic fibre, a wavelength dispersive optic system, outlet optic fibres and a two-wave interferometer. The two-wave interferometer has a spectral response exhibiting minima at twice the frequency of the response of the multiplexer or demultiplexer.

Abstract: A novel method of treating acquired immune deficiency syndromes in warm-blooded animals comprising administering to warm-blooded animals an amount of a non-toxic, pharmaceutically acceptable salt selected from the group consisting of alkali metal, alkaline earth metal and ammonium salts of 9-antimonio-III-21-tungsto-VI-sodate -III-21-tungsto-VI-sodate sufficient to combat acquired immune deficiency syndromes.

Abstract: Compounds containing the heteropolyanion 9-antimoni-III-21-tungsto VI sodate of the formula [NaSb.sub.9 W.sub.21 O.sub.86 ] preferably the ammonium, alkali and alkali metal salts thereof, are active when administered by injection against virus infections, particularly leukemia, sarcoma and encephalomyocardia virus, as shown, by tests in vitro and in vivo in mice.