varieties of st. john’s wort (hypericum perforatum l.) native to iran possess the largest percentage of hypercin in their leaves and flowers. isotherm curves show the relationship between the relative humidity and moisture content of the plant at a constant temperature. it is essential to understand the isotherms curves for successful storage and drying of the plant. this study used adsorption ...

Background: Inclusion of inhomogeneity corrections in intensity modulated small fields always makes conformal irradiation of lung tumor very complicated in accurate dose delivery.Objective: In the present study, the performance of five algorithms via Monte Carlo, Pencil Beam, Convolution, Fast Superposition and Superposition were evaluated in lung cancer Intensity Modulated Radiotherapy plannin...

Background: Monte Carlo determination of TG-43 brachytherapy dosimetry parameters and dose distribution calculation for 131Cs source model CS-1 are presented in this study. Materials and Methods: The dose distribution was calculated around the 131Cs Model CS-1 located in the center of 30 cm ×30 cm ×30 cm water, and soft tissue phantoms cube using MCNP code by Monte Carlo method. The percentage ...

Elliptic curve cryptosystems (ECC) are new generations of public key cryptosystems that have a smaller key size for the same level of security. The exponentiation on elliptic curve is the most important operation in ECC, so when the ECC is put into practice, the major problem is how to enhance the speed of the exponentiation. It is thus of great interest to develop algorithms for exponentiation...

Introduction: GafChromic EBT films are one of the self-developing and modern films commercially available for dosimetric verification of treatment planning systems (TPSs). Their high spatial resolution, low energy dependence and near-tissue equivalence make them suitable for verification of dose distributions in radiation therapy. This study was designed to evaluate the dosimetric parameters of...

The Leksell GammaPlan software version 10 introduces a CT image-based segmentation tool for automatic skull definition and a convolution dose calculation algorithm for tissue inhomogeneity correction. The purpose of this work was to evaluate the impact of these new approaches on routine clinical Gamma Knife treatment planning. Sixty-five patients who underwent CT image-guided Gamma Knife radios...

Adjuvant irradiation of the resection cavity after craniotomy is a newer application of stereotactic radiosurgery. This technique has been proposed to avoid long-term neurotoxicity of whole-brain radiation therapy, and seems to afford comparable local control rates in the multiple published retrospective series so far. Currently, many questions remain to be answered to define the optimal patien...