Geant4 Simulation of Gamma-Ray Transmission Buildup Factors for Human Tissues.

Quantification of scattered photons in addition to unscattered primary particles, under realistic exposure scenario, is best dealt with a parameter called "Buildup factor". The aim of this work is to simulate the transmission buildup factor (BUF) of gamma-ray in the energy range .15-15 MeV for 20 human tissues and organs using the Geant4 (version 10.

Simulation of Gamma-Ray Transmission Buildup Factors for Stratified Spherical Layers.

Deterministic particle transport codes usually take into account scattered photons with correct attenuation laws and application of buildup factor to incident beam. Transmission buildup factors for adipose, bone, muscle, and skin human tissues, as well as for various combinations of these media for point isotropic photon source with energies of .15, 1.

Investigation of F and Zr Isotopes Self-Absorption and Dose Rate Parameters for PET Imaging.

This work concerns study of self-absorption factor (SAF) and dose rate constants of zirconium-89 (Zr) for the purpose of radiation protection in positron emission tomography (PET) and to compare them with those of F-deoxyglucose (F-FDG). We analyzed the emitted energy spectra by F and Zr through anthropomorphic phantom and calculated the absorbed energy using Monte Carlo method. The dose rate constants for both radionuclides were estimated with 2 different fluence-to-effective dose conversion coefficients.

Enhanced Optical and Antibacterial Activity of Hydrothermally Synthesized Cobalt-Doped Zinc Oxide Cylindrical Microcrystals.

Cobalt (Co) doped zinc oxide (ZnO) microcrystals (MCs) are prepared by using the hydrothermal method from the precursor's mixture of zinc chloride (ZnCl), cobalt-II chloride hexahydrate (CoCl·6HO), and potassium hydroxide (KOH). The smooth round cylindrical morphologies of the synthesized microcrystals of Co-doped ZnO show an increase in absorption with the cobalt doping. The antibacterial activity of the as-obtained Co-doped ZnO-MCs was tested against the bacterial strains of gram-negative (, ) and gram-positive bacteria (, ) via the agar well diffusion method.

Breast Cancer Epidemiology in Gulf Cooperation Council Countries: A Regional and International Comparison.

Breast cancer is the most frequently diagnosed noncutaneous malignancy in women living in Gulf Cooperation Council countries. The present report aimed to highlight the similarities and variations in breast cancer incidence, age at diagnosis, clinicopathologic features, molecular characteristics, and lifestyle factors that contribute to an increasing incidence of breast cancer compared with neighboring Arab and westernized countries. The data presented, although having important implications for policy makers, also highlights the need for further research.