The priming dose effect, called also the Raper–Yonezawa effect or simply the Yonezawa effect, is a special case of the radiation adaptive response phenomenon (radioadaptation), which refers to: (a) faster repair of direct DNA lesions (damage), and (b) DNA mutation frequency reduction after irradiation, by applying a small priming (conditioning) dose prior to the high detrimental (challenging) one. This effect is observed in many (but not all) radiobiological experiments which present the reduction of lesion, mutation or even mortality frequency of the irradiated cells or species. Additionally, the multi-parameter model created by Dr. Yonezawa and collaborators tried to explain it theoretically based on experimental data on the mortality of mice with chronic internal irradiation. The presented paper proposes a new theoretical approach to understanding and explaining the priming dose effect: it starts from the radiation adaptive response theory and moves to the three-parameter model, separately for two previously mentioned situations: creation of fast (lesions) and delayed damage (mutations). The proposed biophysical model was applied to experimental data—lesions in human lymphocytes and chromosomal inversions in mice—and was shown to be able to predict the Yonezawa effect for future investigations. It was also found that the strongest radioadaptation is correlated with the weakest cellular radiosensitivity. Additional discussions were focussed on more general situations where many small priming doses are used.

This article presents the Polish project entitled ‘Detektory dla Szkół’ (‘Detectors for Schools’, throughout the paper referred to as ‘the programme’). It was developed at the Education and Training Division of the National Centre for Nuclear Research (Narodowe Centrum Badań Jądrowych, NCBJ) in Poland. The programme allows the schools to borrow from NCBJ two types of radiation detectors: Geiger–Müller counter and CosmicWatch detector(s). Student participation in the measurements is expected.

With 15 years of experience, the jurors of a Polish student competition entitled Footpaths of Physics present their views on the copycat approach manifested by the contestants. The cases discussed are analysed in order to discover the reasons and results of such an attitude – connected to the competition itself, as well as to more general psychological and societal phenomena. The paper may be treated as a set of clues for people engaged in judging the work of students – such as teachers – but also for anyone working with exceptionally gifted or ambitious students.

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This review article describes our simplified biophysical model for the response of a group of cells to ionizing radiation. The model, which is a product of 10 years of studies, acts as (a) a comprehensive stochastic approach based on the Monte Carlo simulation with a probability tree and (b) the thereof derived detailed deterministic models describing the selected biophysical and radiobiological phenomena in an analytical manner. Specifically, the presented model describes effects such as the risk of neoplastic transformation of cells relative to the absorbed radiation dose, the dynamics of tumor development, the priming dose effect (also called the Raper–Yonezawa effect) based on the introduced adaptive response approach, and the bystander effect. The model is also modifiable depending on users’ potential needs.