The need for more accurate radiation therapy treatment planning is driving improvements in radiation transport calculations. In particular, the inclusion of patient specific anatomy and tissue density heterogeneities will be very important, particularly for treatment modalities that involve strong material discontinuities. The study presented here compares the application of the deterministic c...

The Low Energy Neutron Source (LENS) is based on Be(p,xn) reactions at proton energy up to 13 MeV. Its novel design employs a cylindrical light water reflector/moderator surrounding the Be target primary neutron source and a solid CH4 cold neutron moderator downstream from the Be target that is coupled to the reflector. The design of the Target/Moderator/Reflector (TMR) assembly was optimized w...

Introduction: Due to nuclear interactions between the tissues and high-energy protons, the particles, including neutrons, positrons, and photons arise during proton therapy. This study aimed at investigating the dose distribution of proton and secondary particles, such as positrons, neutrons, and photons using the Monte Carlo method. Material and Methods:<...

background: the assessment of rbe quantity in the treatment of cancer tumors with proton beams in treatment planning systems (tps) is of high significance. given the significance of the issue and the studies conducted in the literature, this quantity is fixed and is taken as equal to 1.1. objective: the main objective of this study was to assess rbe quantity of proton beams and their variations...

This study explores how the metal materials of the applicator influence the dose distribution when performing brachytherapy for cervical cancer. A pinpoint ionization chamber, Monte Carlo code MCNPX, and treatment planning system are used to evaluate the dose distribution for a single Ir-192 source positioned in the tandem and ovoid. For dose distribution in water with the presence of the tande...

background: combination antiplatelet therapy is a classic treatment for percutaneous coronary intervention (pci) but this therapy increases gastrointestinal bleeding (gib). this study highlights the incidence of related risk factors of gib and endoscopic findings in patients with gib after pci and combination antiplatelet therapy. materials and methods: a standard check list was used to evaluat...

This paper presents the Monte Carlo simulation of the Positron Emission Tomography (PET) scanning technique using MCNPX code. The raw data generated by general MCNPX code contain a lot of unnecessary information for the image reconstruction process. This requires a large memory to store all this information. In order to reduce the needed memory, we introduce some modifications on the MCNPX code...

Background: The purpose of this paper is to establish an easy and reliable biodosimeter protocol to evaluate the biological effects of proton beams. Materials and Methods: Human peripheral blood lymphocytes were irradiated using proton beams (LET: 34.6 keV μm−1), and the chromosome aberrations induced were analyzed using cytokinesis-blocked (CB) micronucleus (MN) assay. To determine th...