Dose distribution evaluation in oncological radiotherapy treatments is an outstanding problem that requires sophisticated computing technologies to optimize the clinical results (i.e. increase the dose to the tumour and reduce the dose to the healthy tissues). Nowdays, dose calculation algorithms based on the Monte Carlo method are generally regarded as the most accurate tools for radiotherapy....

The Monte Carlo calculation of the effective (i.e. adjoint weighted) neutron generation time Keff, especially for continuous energy simulations, is not straightforward nor standard in Monte Carlo codes. The use of the non-adjoint weighted neutron generation time K (standard in most Monte Carlo codes) as an approximation of the effective one can lead to a serious bias. We show here that the diff...

Monte Carlo techniques have become ubiquitous in medical physics over the last 50 years with a doubling of papers on the subject every 5 years between the first PMB paper in 1967 and 2000 when the numbers levelled off. While recognizing the many other roles that Monte Carlo techniques have played in medical physics, this review emphasizes techniques for electron-photon transport simulations. Th...

MOTIVATION Monte Carlo methods are the most effective means of exploring the energy landscapes of protein folding. The rugged topography of folding energy landscapes causes sampling inefficiencies however, particularly at low, physiological temperatures. RESULTS A hybrid Monte Carlo method, termed density guided importance sampling (DGIS), is presented that overcomes these sampling inefficien...

Assessment of secondary particles in breast proton therapy by Monte Carlo simulation code using MCNPX

one of known methods for measuring, forecasting and managing risk is value at risk, which recently has been used by financial institutions extensively. value at risk (var) is a method for recognizing and evaluating risk and uses standard statistical techniques that have daily using in other contexts. this research is seeking a career for managing investment risk in stock exchange and selection ...

Purpose A Monte Carlo model of a 6 MV medical linear accelerator (linac) unit built indigenously was developed using the BEAMnrc user code of the EGSnrc code system. The model was benchmarked against the measurements. Monte Carlo simulations were carried out for different incident electron beam parameters in the study. Materials and Methods Simulation of indigenously developed linac unit has ...

Objective: Brachytherapy sources are widely used for the treatment of cancer. The report of Task Group No. 43 (TG-43) of American Association of Physicists in Medicine is known as the most common method for the determination of dosimetric parameters for brachytherapy sources. The aim of this study is to obtain TG-43 dosimetric parameters for 60Co, 137Cs, 192Ir and 103Pd brachyt...

Depth-dose curves for cobalt photon beams were experimentally determined in homogeneous acrylic phantoms and compared to dose distributions calculated by Monte Carlo simulation. The measurements of the depth-dose curves were performed with L-alanine minidosimeters, Kodak X-Omat V radiographic films and with cylindrical ionization chambers. The Co source and the phantom and Lalanine minidosimete...

in this study, monte carlo statistical mechanical simulations for vinblastine and vincristine werecarried out in standard manner using the metropolis sampling technique in canonical (t, v, n)ensemble., geometrical optimizations of vinblastine and vincristine were carried out with the hfmethod coupled to 6-31g(d) basis sets for all atoms. simulation was done by four force fields ofmm+, bio+, amb...