Monte Carlo (MC) track structure simulation tools are commonly used for predicting radiation induced DNA damage by modeling the physical and chemical reactions at the nanometer scale. However, the outcome of these MC simulations is particularly sensitive to the adopted parameters which vary significantly across studies. In this study, a previously developed full model of nuclear DNA was used to describe the DNA geometry. The TOPAS-nBio MC toolkit was used to investigate the impact of physics and chemistry models as well as three key parameters (the energy threshold for direct damage, the chemical stage time length, and the probability of damage between hydroxyl radical reactions with DNA) on the induction of DNA damage. Our results show that the difference in physics and chemistry models alone can cause differences up to 34% and 16% in the DNA double strand break (DSB) yield, respectively. Additionally, changing the direct damage threshold, chemical stage length, and hydroxyl damage probability can cause differences of up to 28%, 51%, and 71% in predicted DSB yields, respectively, for the configurations in this study.

中文翻译：

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使用TOPAS-nBio进行质子辐照后模拟DNA损伤的参数敏感性研究。

蒙特卡洛（MC）轨道结构仿真工具通常用于通过对纳米级的物理和化学反应进行建模来预测辐射引起的DNA损伤。但是，这些MC模拟的结果对所采用的参数特别敏感，这些参数在各个研究中差异很大。在这项研究中，以前开发的完整核DNA模型用于描述DNA几何形状。TOPAS-nBio MC工具包用于研究物理和化学模型以及三个关键参数（直接损伤的能量阈值，化学阶段时间长度以及羟基自由基与DNA之间的损伤可能性）的影响。 DNA损伤的诱导。我们的结果表明，仅物理模型和化学模型的差异会分别导致DNA双链断裂（DSB）产量差异分别达到34％和16％。此外，对于本研究中的配置，更改直接破坏阈值，化学阶段长度和羟基破坏概率可能分别导致预测DSB产量的差异分别高达28％，51％和71％。