Abstract: A radiation indicator device for use in indicating exposure to ultraviolet-B radiation. The device includes a radiation sensitive mixture which is selectively responsive to ultraviolet radiation having a wavelength substantially within or shorter than the range of wavelengths of ultraviolet-B radiation. The radiation sensitive mixture includes an organic halogen constituent capable of producing at least one acidic product upon exposure to ultraviolet radiation and an indicator constituent capable of producing a change in color in response to a change in concentration of the acidic product. The radiation sensitive mixture has a first color representing a relatively low concentration of the acidic product and has a second color representing a relatively high concentration of the acidic product. The first color is visually distinguishable from the second color.

Abstract: Novel nucleosides are provided having at least one hydrogen or hydroxide substitutent replaced by a .gamma.-emitting halogen. Methods of preparation of these nucleosides are provided and also a novel non-invasive method for the detection and measurement of tissue hypoxia in mammals.

Abstract: A variable time integrating period to accomplish distortion free synchronization of the scanning rate to the document transport speed when the transport speed is within a predetermined tolerance with respect to it's nominal speed is disclosed. The rate levels provided by the scanner are then multiplied by an appropriate correction factor to compensate for the varied amount of light accumulated by the time integrating photo sensor array because of the varied integration time. When the document speed must be reduced to a value less than the predetermined tolerance, the system of the invention resorts to the techinque of selecting only certain scans and discarding the data from other scans. Scan selection is found to be economically accomplished by selecting those scans which were time integrating when an emitter pulse occurred.