the interaction between the solute and the solsent molecules play a crucial role in understanding the various molecular processes involved in chemistry and biochemistry, so in this work the potential energy of active site of azurin have been calculated in solvent by the monte carlo simulation. in this paper we present quantitative results of monte carlo calculations of potential energies of ...

High-dimensional feature selection arises in many areas of modern sciences. For example, in genomic research we want to find the genes that can be used to separate tissues of different classes (eg. cancer and normal) from tens of thousands of genes that are active (expressed) in certain tissue cells. To this end, we wish to fit regression and classification models with a large number of feature...

Introduction: Clinical application of encapsulated radioactive brachytherapy sources has a major role in cancer treatment. In the present research, the effects of different tissue densities on the dose distribution of a 103Pd brachytherapy source in a spherical phantom of 50 cm radius have been studied. Material and Methods: As is well known, absorbed dose in tissue depends to its density, but ...

to determine the normal ranges of serum age-related prostate-specific antigen (psa) level in men from beijing area without cancer.in this cross sectional study, form april 2010 to october 2011, 1611 healthy men undergoing a routine health check-up in our hospital and all men received three examinations including serum psa test, digital rectal ex-amination and transrectal ultrasound. men with an...

for superficial lesions, the electrons may be used for radiation therapy. the high energy photons and electrons are produced by a linear accelerator (linac).   many of electron fields need the shielding of normal or critical organs. the electron shields are usually lead slabs with few millimeter thickness which should be placed near the skin, less than 1 centimeter away from skin. in the inspec...

introduction after the publication of task group number 43 dose calculation formalism by the american association of physicists in medicine (aapm), this method has been known as the most common dose calculation method in brachytherapy treatment planning. in this formalism, the water phantom is introduced as the reference dosimetry phantom, while the attenuation coefficient of the sources in the...

Objective: Radiation dose calculations in the prostate brachytherapy practices have very high importance terms of success treatment. The purpose present study is to determine whether there a significant difference between radiation performed water medium and cancer-diagnosed patients by using Monte Carlo method.
 Methods: were on 20 BrachyDose code. Phantom geometry derived from real compu...

background: recently, it has been indicated that x-ray coherent scatter from biological tissues can be used to access signature of tissue. some scientists are interested in studying this effect to get early detection of breast cancer. since experimental methods for optimization are time consuming and expensive, some scientists suggest using simulation. monte carlo (mc) codes are the best option...

Many scientific investigations generate both longitudinal data and survival data. Methods for the combined analysis of both kinds of data have been developed in recent years, with the main emphasis being on modeling and estimation. In cancer research it is common for there to be long term survivors or cured patients and methods have been developed to analyze such data. In this article, we revie...