UV spectroscopy and spectropolarimetry hold the key to understanding certain aspects of massive stars that are largely inaccessible with optical or longer wavelength observations. This is especially true for rapidly-rotating Be Bn stars, owing their high temperatures, geometric asymmetries, binary properties, evolutionary history. spectropolarimetric observations extremely sensitive photospheri...

The rate of tumor induction by UV-A radiation rises more slowly with time and accumulated dose than that by UV-B radiation. It has recently been shown that this difference disappears when frank papillomas are excluded from the analysis. Thus, the rate of development of "nonpapillomas" (mainly squamous cell carcinomas and precursors) can be fully characterized by a typical tumor induction time, ...