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The generation of cold physical plasma at atmospheric pressure (cold atmospheric plasma: CAP) generates different reactive molecular species as well as radiation in the ultraviolet (UV) range. The therapy of tumor diseases has proven to be a new promising area of application for CAP treatment. With regard to the routine use of CAP in cancer therapy, however, application safety must be ensured both for the patient and for the operator. In this study, the intensity of UVC radiation of the CAP device MiniJet-R (HF Technik, Aachen, Germany) was measured in the range from 220 to 280 nm depending on various device-specific parameters. Depending on the distance to the CAP flame, the UVC intensity reaches values up to 124.5±11 mW m. It should be noted here that the UVC radiation generated by the CAP is emitted in all orientations in the room but is also shielded by the geometry of the handpiece of the CAP device. The device-specific settings for the flow rate of the carrier gas, argon, and the power level at the high-frequency (HF) generator of the CAP device also influence the intensity of the UVC radiation. With regard to the medical use of the CAP device, it can be stated that there is an exposure to UVC radiation, which, depending on the duration of treatment, can also be above the maximum value legally specified in Europe. Shielding components on the CAP device can reduce UVC exposure to the operator as well as adverse side effects to the patient.

Accurate and precise dating is vital to our understanding of the Middle to Upper Paleolithic transition. There are, however, a number of uncertainties in the chronologies currently available for this period. We attempt to examine these uncertainties by utilizing a number of recent developments in the field. These include: the precise dating of the Campanian Ignimbrite (CI) tephra by 40Ar/39Ar; the tracing of this tephra to a number of deposits that are radiocarbon dated; the publication of revised radiocarbon calibration data for the period, showing a much better convergence with other available data than during the recent IntCal comparison; and a layer-counted ice-core chronology extending beyond 40,000cal BP. Our data comparisons suggest that a reasonable overall convergence between calibrated radiocarbon ages and calendar dates is possible using the new curves. Additionally, we suggest that charcoal-based radiocarbon ages, as well as bone-based radiocarbon determinations, require cautious interpretation in this period. Potentially, these issues extend far beyond the sites in this study and should be of serious concern to archaeologists studying the Middle to Upper Paleolithic. We conclude by outlining a strategy for moving the science forward by a closer integration of archaeology, chronology, and stratigraphy.