An Explainable MRI-Radiomic Quantum Neural Network to Differentiate Between Large Brain Metastases and High-Grade Glioma Using Quantum Annealing for Feature Selection.

Solitary large brain metastases (LBM) and high-grade gliomas (HGG) are sometimes hard to differentiate on MRI. The management differs significantly between these two entities, and non-invasive methods that help differentiate between them are eagerly needed to avoid potentially morbid biopsies and surgical procedures. We explore herein the performance and interpretability of an MRI-radiomics variational quantum neural network (QNN) using a quantum-annealing mutual-information (MI) feature selection approach.

Time-Dependent Density-Functional Theory for Determining the Electron-Capture Cross Section for Protons Impacting on Atoms and Molecules.

The use of the Time-Dependent Density-Functional Theory (TDDFT) has increased in the atomic collision field. Calculating the electron-capture cross section (ECCS) for protons is an important question in hadrontherapy and plasma physics, among other areas. In previous studies, it was shown that the approach based on the Local Density Approximation (LDA) fails in the 1-50 keV region, requiring the use of the Optimized Effective Potential (OEP) method.

Prediction of DNA rejoining kinetics and cell survival after proton irradiation for V79 cells using Geant4-DNA.

Purpose: Track structure Monte Carlo (MC) codes have achieved successful outcomes in the quantitative investigation of radiation-induced initial DNA damage. The aim of the present study is to extend a Geant4-DNA radiobiological application by incorporating a feature allowing for the prediction of DNA rejoining kinetics and corresponding cell surviving fraction along time after irradiation, for a Chinese hamster V79 cell line, which is one of the most popular and widely investigated cell lines in radiobiology.

Methods: We implemented the Two-Lesion Kinetics (TLK) model, originally proposed by Stewart, which allows for simulations to calculate residual DNA damage and surviving fraction along time via the number of initial DNA damage and its complexity as inputs.

Electron tracks simulation in water: Performance comparison between GPU CPU and the EUMED grid installation.

Purpose: We explored different technologies to minimize simulation time of the Monte-Carlo method for track generation following the Geant4-DNA processes for electrons in water.

Methods: A GPU software tool is developed for electron track simulations. A similar CPU version is also developed using the same collision models.

A Geant4-DNA Evaluation of Radiation-Induced DNA Damage on a Human Fibroblast.

Accurately modeling the radiobiological mechanisms responsible for the induction of DNA damage remains a major scientific challenge, particularly for understanding the effects of low doses of ionizing radiation on living beings, such as the induction of carcinogenesis. A computational approach based on the Monte Carlo technique to simulate track structures in a biological medium is currently the most reliable method for calculating the early effects induced by ionizing radiation on DNA, the primary cellular target of such effects. The Geant4-DNA Monte Carlo toolkit can simulate not only the physical, but also the physico-chemical and chemical stages of water radiolysis.

Monte Carlo Simulation of SARS-CoV-2 Radiation-Induced Inactivation for Vaccine Development.

Immunization with an inactivated virus is one of the strategies currently being tested towards developing a SARS-CoV-2 vaccine. One of the methods used to inactivate viruses is exposure to high doses of ionizing radiation to damage their nucleic acids. While gamma (γ) rays effectively induce lesions in the RNA, envelope proteins are also highly damaged in the process.

Assessment of Radio-Induced Damage in Endothelial Cells Irradiated with 40 kVp, 220 kVp, and 4 MV X-rays by Means of Micro and Nanodosimetric Calculations.

The objective of this work was to study the differences in terms of early biological effects that might exist between different X-rays energies by using a mechanistic approach. To this end, radiobiological experiments exposing cell monolayers to three X-ray energies were performed in order to assess the yields of early DNA damage, in particular of double-strand breaks (DSBs). The simulation of these irradiations was set in order to understand the differences in the obtained experimental results.

Determination of fast neutron RBE using a fully mechanistic computational model.

This work presents a model previously developed for estimating relative biological effectiveness (RBE) associated with high-LET particles. It is based on the combination of Monte Carlo simulations of particle interactions when traversing an atomic resolution DNA geometrical model. In addition, the model emulates the induction of lethal damage from the interaction of two sublethal lesions, taken as double-strand breaks.

Computational approach to determine the relative biological effectiveness of fast neutrons using the Geant4-DNA toolkit and a DNA atomic model from the Protein Data Bank.

This study proposes an innovative approach to estimate relative biological effectiveness (RBE) of fast neutrons using the Geant4 toolkit. The Geant4-DNA version cannot track heavy ions below 0.5 MeV/nucleon.

Evaluation of early radiation DNA damage in a fractal cell nucleus model using Geant4-DNA.

The advancement of multidisciplinary research fields dealing with ionising radiation induced biological damage - radiobiology, radiation physics, radiation protection and, in particular, medical physics - requires a clear mechanistic understanding of how cellular damage is induced by ionising radiation. Monte Carlo (MC) simulations provide a promising approach for the mechanistic simulation of radiation transport and radiation chemistry, towards the in silico simulation of early biological damage. We have recently developed a fully integrated MC simulation that calculates early single strand breaks (SSBs) and double strand breaks (DSBs) in a fractal chromatin based human cell nucleus model.

Accounting for radiation-induced indirect damage on DNA with the Geant 4-DNA code.

The use of Monte Carlo (MC) simulations remains a powerful tool to study the biological effects induced by ionizing radiation on living beings. Several MC codes are commonly used in research fields such as nanodosimetry, radiotherapy, radiation protection, and space radiation. This work presents an enhancement of an existing model [1] for radiobiological purposes, to account for the indirect DNA damage induced by ionizing particles.

Numerical insight into the Dual Radiation Action Theory.

This work studies the first and second order mechanisms for the induction of lethal lesions in DNA after irradiation with protons and α-particles. The purpose is to numerically study the mechanisms behind the Dual Radiation Action Theory (DRAT) for these heavy particles. A genetic material geometrical model with atomic resolution is used.

A study on the physicochemical parameters for Penicillium expansum growth and patulin production: effect of temperature, pH, and water activity.

Penicillium expansum is among the most ubiquitous fungi disseminated worldwide, that could threaten the fruit sector by secreting patulin, a toxic secondary metabolite. Nevertheless, we lack sufficient data regarding the growth and the toxigenesis conditions of this species. This work enables a clear differentiation between the favorable conditions to the P.

Analysis of the EBT3 Gafchromic film irradiated with 6 MV photons and 6 MeV electrons using reflective mode scanners.

We explore in our study the effects of electrons and X-rays irradiations on the newest version of the Gafchromic EBT3 film. Experiments are performed using the Varian "TrueBeam 1.6" medical accelerator delivering 6 MV X-ray photons and 6 MeV electron beams as desired.

Simulation of DNA damage clustering after proton irradiation using an adapted DBSCAN algorithm.

In this work the "Density Based Spatial Clustering of Applications with Noise" (DBSCAN) algorithm was adapted to early stage DNA damage clustering calculations. The resulting algorithm takes into account the distribution of energy deposit induced by ionising particles and a damage probability function that depends on the total energy deposit amount. Proton track simulations were carried out in small micrometric volumes representing small DNA containments.

Methylene blue dye, an accurate dye for sentinel lymph node identification in early breast cancer.

Purpose: The aim of this prospective study was to analyze the safety of methylene blue dye (MBD) and compare its efficacy with that of isotopic mapping for sentinel lymph node (SLN) identification in breast cancer.

Patients And Methods: The SLN procedure, involving isotopic mapping and MBD (subareolar intraparenchymal injections of 2 mL, 10 mg/mL), was performed on 100 patients with early breast cancer.

Results: The procedure was safe with a success rate of 99%; SLNs were, respectively, found in 65% by MBD, in 73% by lymphoscintigraphy and in 94% by gamma-probe.