Background: Monte Carlo method (MC) has played an important role in design and optimization of medical linacs head and beam modeling. The purpose of this study was to compare photon beam features of two commercial linacs, Varian 21EX and Elekta SL-25 using MCNP4C MC code. Materials and Methods: The 6MV photon beams of Varian 21EX and Elekta Sl-25 linacs were simulated based on manufacturers pro...

Scatterometer Contamination Mitigation

Introduction: In clinical electron beams, most of bremsstrahlung radiation is produced by various linac head structures. This bremsstrahlung radiation dose is influenced by the geometry and construction of every component of the linac treatment head structures. Thus, it can be expected that the amount of the contaminated photon dose due to bremsstrahlung radiation varies among different linacs,...

The present work investigates the masking effect of carbon contamination patterns deposited by the electron-beam ~E-beam! of a scanning electron microscope ~SEM! for metal electrodeposition reactions. Carbon contamination lines were written at different electron doses on n-type Si~100! surfaces. Subsequently Au was electrochemically deposited from a 1 M KCN 1 0.01 M KAu~CN!2 solution on the E-b...

Our institution performs in vivo verification measurement for each of our total body irradiation (TBI) patients with optically stimulated luminescent dosimeters (OSLD). The lung block verification measurements were commonly higher than expected. The aim of this work is to understand this discrepancy and improve the accuracy of these lung block verification measurements. Initially, the thickness...

objectives: osteoblasts are the most important cells in the osseointegration process. despite years of study on dental implants, limited studies have discussed the effect of saliva on the adhesion process of osteoblasts to implant surfaces. the aim of this in vitro study was to evaluate the effect of saliva on morphology and differentiation of osteoblasts attached to implant surfaces. materials...

The presence of cholinesterase activity in M. demissus hearts was demonstrated by light- and electron-microscopic histochemistry and by enzymic assay. The enzyme proved to be acetylcholinesterase (AChE) since acetylthiocholine was the preferred substrate, and eserine or BW284C5I inhibited the enzyme activity, while isoOMPA was without effect. The AChE was localized and uniformly distributed alo...