RESUMO
In view of the upcoming radiation therapy with carbon ions, the ionisation structure of the carbon ion track at the nanometre scale is of particular interest. Two different nanodosimeters capable of measuring track structure of ionising particles in a gas target equivalent to a nanometric site in condensed matter were involved in the presented experimental investigation, namely the NCBJ Jet Counter and the PTB Ion Counter. At the accelerator facility of the HIL in Warsaw, simulated nanometric volumes were irradiated with carbon ions of 45 and 76 MeV of kinetic energy, corresponding to a range in the tissue of â¼85 µm and â¼190 µm, respectively. The filling gas of both nanodosimeters' ionisation volume was molecular nitrogen N2, and the ionisation cluster size distributions, i.e. the statistical distribution of the number of ionizations produced by one single primary carbon ion in the filling gas, were measured for the two primary particle energies.
Assuntos
Carbono/química , Nanotecnologia/métodos , Nitrogênio , Aceleradores de Partículas/instrumentação , Radiometria/instrumentação , Calibragem , Simulação por Computador , Desenho de Equipamento , Doses de RadiaçãoRESUMO
Chinese hamster ovary CHO-K1 cells were exposed to high LET (12)C-beam (LET: 830 keV/microm) in the dose range of 0-6 Gy and to (60)Co irradiation and the RBE value was obtained. Effects of (12)C-beam exposure on cell survival and chromosomal aberrations were calculated. The chromosomal aberration data were fitted with linear equation. The distribution of aberration in cells was examined with a standard u-test and used to evaluate the data according to Poisson probabilities. The variance to the mean ratio sigma(2)/Y and the dispersion index (u) were determined. Overdispersion was significant (p<0.05) when the value of u exceeded 1.96.
Assuntos
Radioisótopos de Carbono , Sobrevivência Celular/efeitos da radiação , Aberrações Cromossômicas/efeitos da radiação , Animais , Células CHO/efeitos da radiação , Cricetinae , Cricetulus , Íons , Distribuição de Poisson , RadiaçãoRESUMO
A facility with a horizontal beam for radiobiological experiments with heavy ions has been designed and constructed at the Heavy Ion Laboratory in Warsaw University. The facility is optimal to investigate the radiobiological effects of charged heavy particles on a cellular or molecular level as in the region of the Bragg peak.
Assuntos
Técnicas de Cultura de Células/instrumentação , Fenômenos Fisiológicos Celulares/efeitos da radiação , Ciclotrons/instrumentação , Íons Pesados , Aceleradores de Partículas/instrumentação , Radiobiologia/instrumentação , Técnicas de Cultura de Células/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Polônia , Doses de Radiação , Radiobiologia/métodos , Espalhamento de RadiaçãoRESUMO
Gamma spectra were measured and activities of the detected isotopes were analyzed for 206 high-activity particles (hot particles, HPs) found in northeastern Poland after the Chernobyl accident. The isotopic composition of HPs observed in gamma-activity is compared with that of the general fallout and core inventory calculations. Particle formation and a process of depletion in Ru and Cs isotopes are discussed. On the basis of a search performed a year later, some comments on the behavior of HPs in the soil are made.
