Single-color illumination of a copper surface by a red or an ultraviolet femtosecond laser pulse yields a threephoton (red) or a two-photon (UV) photoemission process. A multicolor, multiphoton process is generated when the red and the UV pulses overlap both in space and in time on the photocathode. It is shown that this emission process results from the absorption by an electron of one red and...

This protocol describes how to mutagenize spores and protonemal tissue from moss (Physcomitrella patens) using chemicals or ultraviolet (UV) light. Spores are mutagenized using the alkylating agents N-methyl-N′-nitro-N-nitrosoguanidine (NTG) and ethyl methanesulfonate (EMS), and protonemal tissue is mutagenized with NTG and UV light. Compared to alkylating agents, UV is less effective as a muta...

The Ozone Monitoring Instrument (OMI) onboard the NASA EOS Aura spacecraft is a nadir viewing spectrometer that measures solar reflected and backscattered light in a selected range of the ultraviolet and visible spectrum. The instrument has a 2600 km wide viewing swath and it is capable of daily, global contiguous mapping. We have developed and implemented a surface ultraviolet irradiance algor...

Abstract. We report on applications of the ultraviolet-light-emitting-diode-based incoherent broadband cavity-enhanced absorption spectroscopy (UV-LED-IBBCEAS) technique for optical monitoring HONO, NO2 and CH2O in a simulation chamber. Performance intercomparison UV-LED-IBBCEAS with wet chemistry-based NitroMAC sensor Fourier transform infrared (FTIR) spectrometer has been carried out real-tim...

We have examined the consequences of Ultraviolet-B (UV-B) irradiation in the thallus of the lichen Physcia semipinnata (J.F.Gmel) in terms of cell viability and apoptotic-like formation. UV-B induced oligonucleosomal DNA fragmentation was detected by TUNEL assay and this is the first study showing DNA fragmentation in thalli. The intensity of TUNEL-positive cells after exposure to UV-B at doses...

When CV-1 mammalian cells were X-irradiated before infection with ultraviolet (UV)-irradiated herpes simplex virus, an increase in survival of this virus was observed. X-ray reactivation is proposed as the name of this phenomenon by analogy with UV reactivation. The amount of survival enhancement was about the same as that found for UV reactivation in the same virus-host system. The enhancement...

We present a unified model of optical and ultraviolet (UV) light curves for one of the fastest classical novae, V838 Herculis (Nova Herculis 1991), and estimate its white dwarf (WD) mass. Based on an optically thick wind theory of nova outbursts, we model the optical light curves with free-free emission and the UV 1455 Å light curves with blackbody emission. Our models of 1.35 ± 0.02 M⊙ WD repr...

A photocrosslinkable trehalose derivative carrying mesogenic groups was synthesized by esterification reactions. The derivative (TC-HBPHA) was synthesized by the reaction of partially cinnamoyl-modified trehalose (TC4) with 4-(4-hexyloxybenzoyloxy)phenoxy-6-oxohexanoic acid (HBPHA) as a mesogenic unit. TC-HBPHA showed a nematic liquid crystalline mesophase at a temperature range from 150 °C to ...

In order to image noninvasively cell nuclei in vivo without staining, we have developed ultraviolet photoacoustic microscopy (UV-PAM), in which ultraviolet light excites nucleic acids in cell nuclei to produce photoacoustic waves. Equipped with a tunable laser system, the UV-PAM was applied to in vivo imaging of cell nuclei in small animals. We found that 250 nm was the optimal wavelength for i...

The products of the reaction of OClO with NO3 were investigated between 220 and 298 K using a flow reactor and infrared, visible, and ultraviolet analysis. At temperatures below 250 K new infrared and ultraviolet absorption features were observed and assigned to the novel compound chloryl nitrate (OZClON02). Additionally, ClO and NOz were observed as reaction products, indicating the existence ...