Photooxygenation of p-xylene by oxygen occurs efficiently under photoirradiation of 9-mesityl-2,7,10-trimethylacridinium ion (Me(2)Acr(+)-Mes) to yield p-tolualdehyde and hydrogen peroxide, which is initiated via photoinduced electron transfer of Me(2)Acr(+)-Mes to produce the electron-transfer state.

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The simulation and experimental results demonstrated that the phase controlled rescanning method makes it possible to deliver the dose distribution close to the expected one. As an experimental result for 3D irradiation, it was estimated that blurring by the probability density function was not only for a lateral distribution, but also for a distal distribution, even in the lateral rescanning.

As a result of this study, the authors verified that the new scanning delivery system can produce an accurate 3D dose distribution for the target volume in combination with the planning software.

The National Institute of Radiological Sciences (NIRS) has initiated a development project for hypo-fractionated multi-ion therapy. In the treatment, heavy ions up to neon ions will be used as a primary beam, which is a high linear energy transfer (LET) radiation. The fractionated dose of the treatment will be 10 Gy or more. The microdosimetric kinetic (MK) model overestimates the biological effectiveness of high-LET and high-dose radiations. To address this issue, the stochastic microdosimetric kinetic (SMK) model has been developed as an extension of the MK model. By taking the stochastic nature of domain-specific and cell nucleus-specific energies into account, the SMK model could estimate the biological effectiveness of radiations with wide LET and dose ranges. Previously, the accuracy of the SMK model was examined by comparison of estimated and reported survival fractions of human cells exposed to pristine helium-, carbon-, and neon-ion beams. In this study, we verified the SMK model in treatment planning of scanned helium-, carbon-, oxygen-, and neon-ion beams as well as their combinations through the irradiations of human undifferentiated carcinoma and human pancreatic cancer cells. Treatment plans were made with the ion-species beams to achieve a uniform 10% survival of the cells within a cuboid target. The planned survival fractions were reasonably reproduced by the measured survival fractions in the whole region from the plateau to the fragment tail for all planned irradiations. The SMK model offers the accuracy and simplicity required in hypo-fractionated multi-ion therapy treatment planning.