Changes in Ultraviolet Absorption of Sunscreens After Ultraviolet Irradiation

Ultrastructural changes in Euglena after ultraviolet irradiation.

The structural changes associated with the ultraviolet-induced bleaching of light-grown cells of Euglena gracilis were investigated. Our lightand electron-microscopic observations of the bleaching process indicate that there is a continuity of plastid structure in cells 5 generations after receiving a bleaching dose of ultraviolet light. There seems to be a continuous dilution of the plastid th...

Ultraviolet absorption in lenses.

Photostability of commercial sunscreens upon sun exposure and irradiation by ultraviolet lamps

BACKGROUND Sunscreens are being widely used to reduce exposure to harmful ultraviolet (UV) radiation. The fact that some sunscreens are photounstable has been known for many years. Since the UV-absorbing ingredients of sunscreens may be photounstable, especially in the long wavelength region, it is of great interest to determine their degradation during exposure to UV radiation. Our aim was to ...

Ultraviolet germicidal irradiation

Ultraviolet germicidal irradiation (UVGI) is a disinfection method that uses ultraviolet (UV) light at sufficiently short wavelength to kill microorganisms. It is used in a variety of applications, such as food, air and water purification. UV has been a known mutagen at the cellular level for more than one-hundred years. The 1903 Nobel Prize for Medicine was awarded to Niels Finsen for his use ...

Ultraviolet microbeam irradiation

Marginal bands were isolated from newt red blood cells and, using monochromatic light from an ultraviolet microbeam, the marginal band microtubules were irradiated in vitro to produce areas of reduced birefringence (ARBs). The ARBs neither moved nor changed shape after they were formed, though the marginal bands sometimes changed shape during the irradiation. Marginal band ARBs 'were regions in...