EMN for radiation protection - an evolving European metrology network

The European Council DIRECTIVE 2013/59/EURATOM laying down the basic safety standards for protection against the dangers arising from exposure to ionizing radiation is currently the main European regulation on ionizing radiation. The practical implementation of the European basic safety standards has become more complex due to the lack of consideration of the metrological implications and the adaptation to new technological developments, which lead to new standards, technological innovations, and improved capabilities. It was considered by EURAMET to be of a vital importance to have a metrology network that acts as a focal point between the metrology communities and the relevant radiation protection stakeholders, including regulators, standardization bodies, manufacturers, users of radiation sources and international organizations and radiation protection platforms. One of the most important tasks of this European Metrology Network (EMN) for Radiation Protection is to give a strong voice to the field of radiation protection metrology in Europe, so that it can provide responsible guidance and support to future technological developments. Additionally, metrological competence and capacity are essential to determine ambient or occupational exposures and urgent metrological needs exist in case of emergency situations. The EMN for Radiation Protection is in operation since 2021. The first Chair, Annette Röttger (PTB, Germany), Vice-Chair, Teemu Siiskonen (STUK, Finland) and Secretary Behnam Khanbabaee (PTB, Germany) have been elected. At the second meeting in 2022, first actions have been identified. In this contribution, the planned actions and next steps will be presented.ERPW 2022 - European Radiation Protection Week, 9-14th October 2022, Estoril, Portuga

Band bending at the heterointerface of GaAs/InAs core/shell nanowires monitored by synchrotron X-ray photoelectron spectroscopy

Unique electronic properties of semiconductor heterostructured nanowires make them useful for future nano-electronic devices. Here, we present a study of the band bending effect at the heterointerface of GaAs/InAs core/shell nanowires by means of synchrotron based X-ray photoelectron spectroscopy. Different Ga, In, and As core-levels of the nanowire constituents have been monitored prior to and after cleaning from native oxides. The cleaning process mainly affected the As-oxides and was accompanied by an energy shift of the core-level spectra towards lower binding energy, suggesting that the As-oxides turn the nanowire surfaces to n-type. After cleaning, both As and Ga core-levels revealed an energy shift of about -0.3 eV for core/shell compared to core reference nanowires. With respect to depth dependence and in agreement with calculated strain distribution and electron quantum confinement, the observed energy shift is interpreted by band bending of core-levels at the heterointerface between the GaAs nanowire core and the InAs shell

The European Metrology Network for Radiation Protection: Benefits and Challenges

The European regulation on ionizing radiation is essentially laid down in the Council DIRECTIVE 2013/59/EURATOM. This Directive implements the basic safety standards for the protection of humans and the environment against the dangers arising from exposure to ionizing radiation. However, the practical implementation of the European basic safety standards has become more complex due to the lack of consideration of the metrological implications and the adaptation to new technological developments, which lead to new standards, technological innovations, and improved capabilities. It is therefore of vital importance to create a network that acts as a focal point between the metrology communities and the relevant radiation protection stakeholders, including regulators, standardization bodies, manufacturers, users of radiation sources and international organizations and platforms dealing with radiation protection such as HERCA, IAEA and EURADOS. The development of such a metrology network under the umbrella of EURAMET was planned by the consortium of the JNP EMPIR project 19NET03 supportBSS. The plan was successfully evaluated by EURAMET and the European Metrology Network (EMN) for Radiation Protection was approved by the EURAMET General Assembly in June 2021. The EMN for radiation protection will interact with innovative technological developments and has set itself the goal of being the central point of contact in order to cover the metrological needs in radiation protection and to find metrological solutions on a European level. The main challenges for this goal are in the first step the implementation of a long-term ongoing dialogue between the metrology communities and relevant stakeholder groups and, on the other hand, the development of a joint and sustainable European metrology infrastructure that underpins radiation protection regulation. The first step is visualized in this work.ERPW 2021 - European Radiation Protection Week, 22-24th November 2021, Vienna, Austri

Formation and activation induction of primordial follicles using granulosa and cumulus cells conditioned media : ATRABI et al.

Fertility preservation of prepubertal girls subjected to invasive cancer therapy necessitates defining protocols for activation of isolated primordial follicles. Granulosa (GCs) and cumulus cells (CCs) play pivotal role in oocyte development. Although GCs and CCs share some similarities, they differ in growth factors production. The current study was conducted to evaluate the effects of GCs, CCs and their conditioned media on mice primordial follicles activation. One-day-old mice ovaries were subjected to 6-day culture with base medium (BM), GC conditioned medium (GCCM), GC coculture (GCCC), CC conditioned medium (CCCM) or CC coculture (CCCC). Follicular growth and primordial to primary follicle transition was observed during 6-day culture, and follicular activation rate tended to be greater in GCCM than other groups (0.05 <P < 0.10). On Day 6, the expression of phosphatase and tensin homolog (PTEN) in GCCM group was lower than that in BM group (P = 0.020), the expression of phosphoinositide-3-kinase was higher in CCCC group than BM, GCCM and CCCM groups (P < 0.05), and the expression of connexin 37 was greater in the CCCM group as compared with BM, GCCC, and CCCC groups (P < 0.01). In conclusion, the current study showed that condition medium of GCs could enhance in vitro activation of primordial follicles, probably through downregulation of PTEN