Abstract: A method of killing carcinoma cells associated normal cells using light of a predetermined wavelength. The method includes contacting the cells with a chromophor at a given concentration. The chromophor is positively charged and sufficiently lipophilic to be taken up by the mitochondria of the carcinoma cells and is retained substantially longer in the mitochondria of carcinoma cells than in normal cell mitochondria; or it may be taken up in greater quantity by the carcinoma cells than by the normal cells. The chromophor must also have a therapeutic index for light-induced cell killing of at least 500 for light of the predetermined wavelength, and has a therapeutic ratio for light-induced killing of at least 50 for light of said pre-determined wavelength. The cells are then exposed to light of this wavelength.

Abstract: An apparatus and method are provided for magnetically disorienting magnetic particles in a magnetic layer of a web coated recording medium that is designed to be used in the manufacture of flexible disks. Disorientation is achieved by subjecting the particles in a fluid pigment carried on a linear web to a rotating magnetic field that projects into the plane of the fluid layer and is rotated about an axis perpendicular to the plane. The interaction of the rotating field with the magnetic particles also has a smoothing effect on the outer surface of the magnetic layer.