INTRODUCTION Monte Carlo (MC) methods have become the "gold standard" for assessing dose distribution, organ doses and effective dose associated with the exposure, both external and internal, of humans to ionizing radiation. Powerful and sophisticated tools for simulation of radiation transport (for example, MCNP, EGS4) are now widely available. However, these codes are designed for general-pur...

In our most recent study of normal aging, we found decreased concentration of multiple chemicals in the brain of middle-aged subjects, as compared with younger subjects using in vivo proton magnetic resonance spectroscopy ((1)H-MRS). We hypothesized that these age-dependent differences in brain chemistry changes might be a reflection of the multichemical-networking-profile (MCNP) changes during...

Series of mathematical phantoms of human body, given by Oak Ridge National Laboratory (ORNL), was programmed as input files for MCNP-4B code. Detailed check of geometry of these phantoms performed by MCNP-4B, discovered some minor errors, that resulted in overlapping of some organs. Three types of errors were found and described here: (a) colon overlaps with pelvis bone; (b) facial skeleton pen...

An innovative computational tool (DAG-MCNP) has been developed for efficient and accurate 3-D nuclear analysis of geometrically complex fusion systems. Direct coupling with CAD models allows preserving the geometrical details, eliminating possible human error, and faster design iterations. DAG-MCNP has been applied to perform 3-D nuclear analysis for several fusion designs and demonstrated the ...

We have studied the intrinsic organization of macaque striate cortex by tracing the pattern of horseradish peroxidase (HRP)-labeled axons and cell bodies produced by microinjections of HRP into single cortical laminae. Both anterograde and retrograde transport results were used to examine: (1) the pattern of projections from lamina 4C to the superficial layers; (2) the projection from lamina 4C...

Abstract Monte Carlo N-Particle (MCNP) is a widely-used code in nuclear engineering, but it needs high computation times due to the tracking of every single particle and interaction event. This causes shielding optimization using trial-and-error take long complete. It can be solved by multiprocessing, this requires MCNP source which difficult obtain. Therefore, paper aims suggest solution on ho...

Introduction BNCT is an effective method to destroy brain tumoral cells while sparing the healthy tissues. The recommended flux for epithermal neutrons is 109 n/cm2s, which has the most effectiveness on deep-seated tumors. In this paper, it is indicated that using D-T neutron source and optimizing of Beam Shaping Assembly (BSA) leads to treating brain tumors in a reasonable time where all IAEA ...

monte carlo method is a very accurate method to optimize medical diagnostic radiology spectra and simulation of radiation transportation. using mcnp code, radiology and mammography attenuated x-rayspectraweresimulated.the ipem report number 78 was used as a reference to compare with the geant4 and mcnp simulations because of its popularity and wide availability. the results of geant4 in 40kev s...