Modelling the influence of shielding on physical and biological organ doses.

Distributions of "physical" and "biological" dose in different organs were calculated by coupling the FLUKA MC transport code with a geometrical human phantom inserted into a shielding box of variable shape, thickness and material. While the expression "physical dose" refers to the amount of deposited energy per unit mass (in Gy), "biological dose" was modelled with "Complex Lesions" (CL), clustered DNA strand breaks calculated in a previous work based on "event-by-event" track-structure simulations. The yields of complex lesions per cell and per unit dose were calculated for different radiation types and energies, and integrated into a version of FLUKA modified for this purpose, allowing us to estimate the effects of mixed fields.

Cellular communication and bystander effects: a critical review for modelling low-dose radiation action.

Available data suggesting the occurrence of "bystander effects" (i.e. damage induction in cells not traversed by radiation) were collected and critically evaluated, in view of the development of low-dose risk models.