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Quinto, Michele A.

Publications and source records attributed to Quinto, Michele A..

5 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Monte Carlo simulation of proton track structure in biological matter

Here, understanding the radiation-induced effects at the cellular and subcellular levels remains crucial for predicting the evolution of irradiated biological matter. In this context, Monte Carlo track-structure simulations have rapidly emerged among the most suitable and powerful tools. However, most existing Monte Carlo track-structure codes rely heavily on the use of semi-empirical cross sections as well as water as a surrogate for biological matter. In the current work, we report on the up-to-date version of our homemade Monte Carlo code TILDA-V – devoted to the modeling of the slowing-down of 10 keV–100 MeV protons in both water and DNA – where the main collisional processes are described by means of an extensive set of ab initio differential and total cross sections.

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTAN↗
DOE OSTI2015

Water versus DNA: New insights into proton track-structure modeling in radiobiology and radiotherapy

Water is a common surrogate of DNA for modelling the charged particle-induced ionizing processes in living tissue exposed to radiations. The present study aims at scrutinizing the validity of this approximation and then revealing new insights into proton-induced energy transfers by a comparative analysis between water and realistic biological medium. In this context, a self-consistent quantum mechanical modelling of the ionization and electron capture processes is reported within the continuum distorted wave-eikonal initial state framework for both isolated water molecules and DNA components impacted by proton beams. Their respective probability of occurrence-expressed in terms of total cross sections-as well as their energetic signature (potential and kinetic) are assessed in order to clearly emphasize the differences existing between realistic building blocks of living matter and the controverted water-medium surrogate. Thus the consequences in radiobiology and radiotherapy will be discussed in particular in view of treatment planning refinement aiming at better radiotherapy strategies.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2015

Low energy electrons and swift ion track structure in PADC

The current work aims at providing an accurate description of the ion track-structure in poly-allyl dyglycol carbonate (PADC) by using an up-to-date Monte-Carlo code-called TILDA-V (a French acronym for Transport d’Ions Lourds Dans l’Aqua & Vivo). In this simulation the ion track-structure in PADC is mainly described in terms of ejected electrons with a particular attention done to the Low Energy Electrons (LEEs). After a brief reminder of the most important channels through which LEEs are prone to break a chemical bond, we will report on the simulated energetic distributions of LEEs along an ion track in PADC for particular incident energies located on both sides of the Bragg-peak position. Lastly, based on the rare data dealing with LEEs interaction with polymers or organic molecules, we will emphasise the role played by the LEEs in the formation of a latent track in PADC, and more particularly the one played by the sub-ionization electrons.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗
DOE OSTI2014

Theoretical and experimental quantification of doubly and singly differential cross sections for electron-induced ionization of isolated tetrahydrofuran molecules

Electron-induced ionization of the commonly used surrogate of the DNA sugar-phosphate backbone, namely, the tetrahydrofuran molecule, is here theoretically described within the 1 st Born approximation by means of quantum-mechanical approach. Comparisons between theory and recent experiments are reported in terms of doubly and singly differential cross sections.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗