UV‐C emitting nanoscale scintillators can be used to sensitize cancer cells selectively against X‐rays during radiation therapy, due to the lethal DNA lesions caused by UV‐C photons. Unfortunately, nanoscale particles (NPs) show decreased UV‐C emission intensity. In this paper, the influence of different Nd3+ concentrations on the UV‐C emission of micro‐ and nanoscale LuPO4:Pr3+ is investigated upon X‐ray irradiation and vacuum UV excitation (160 nm). Co‐doped LuPO4 results in increased UV‐C emission independent of excitation source due to energy transfer from Nd3+ to Pr3+. The highest UV‐C emission intensity is observed for LuPO4:Pr3+,Nd3+(1%,2.5%) upon X‐ray irradiation. Finally, LuPO4 NPs co‐doped with different dopant concentrations are synthesized, and the biological efficacy of the combined approach (X‐rays and UV‐C) is assessed using the colony formation assay. Cell culture experiments confirm increased cell death compared to X‐rays alone due to the formation of UV‐specific DNA damages, supporting the feasibility of this approach.

This paper presents results of microelectronic device degradation due to total dose as measured on the Combined Release and Radiation Effects Satellite (CRRES). The on-orbit device performance is compared to MIL-STD-883 Method 1019.2 @' CO ground test performance on like devices. Although experimental factors introduce uncertainties, the comparisons show that space degradation reasonably matches high dose rate @'CO testing for many part types, while other part types show significant differences. However, even where differences exist, the degradation is within a factor of three between the space and ground tested parts. Due to the vintage of the parts flown and the unexpectedly short duration of the mission, the space results do not provide a basis for evaluating the changes incorporated into the new MIL-STD-883 Method 1019.4 which addresses dose rate effects in more detail.

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