BACKGROUND The Arabidopsis thaliana HAL3 gene product encodes for an FMN-binding protein (AtHal3) that is related to plant growth and salt and osmotic tolerance. AtHal3 shows sequence homology to ScHal3, a regulatory subunit of the Saccharomyces cerevisae serine/threonine phosphatase PPz1. It has been proposed that AtHal3 and ScHal3 have similar roles in cellular physiology, as Arabidopsis tran...

PURPOSE To develop a method for removing the effect of support arm backscatter from Varian electronic portal imaging devices (EPIDs), improving the dosimetric abilities of the imager. METHODS A physical, kernel based model of the backscatter signal produced during an exposure was developed. The model parameters were determined through an optimization process, comparing measured images without...

Normalize the response of electronic portal imaging device (EPID) is the first step toward an EPID-based standardization of Linear Accelerator (linac) dosimetry quality assurance. In this study, we described an approach to generate two-dimensional (2D) pixel sensitivity maps (PSM) for EPIDs response normalization utilizing an alternative beam and dark-field (ABDF) image acquisition technique an...

PURPOSE To quantify the ability of electronic portal imaging device (EPID) dosimetry used during treatment (in vivo) in detecting variations that can occur in the course of patient treatment. METHODS Images of transmitted radiation from in vivo EPID measurements were converted to a 2D planar dose at isocenter and compared to the treatment planning dose using a prototype software system. Using...

Objectives To develop a method for detecting jaw positions during jaw-tracking delivery to ensure an accurate of radiation patients using electronic portal imaging device (EPID) in the cine mode on linear accelerator radiotherapy.

MrsD from Bacillus sp. HIL-Y85/54728 is a member of the HFCD (homo-oligomeric flavin-containing Cys decarboxylases) family of flavoproteins and is involved in the biosynthesis of the lantibiotic mersacidin. It catalyses the oxidative decarboxylation of the C-terminal cysteine residue of the MrsA precursor peptide of mersacidin, yielding a (Z)-enethiol intermediate as the first step in the forma...

An electronic portal imaging device (EPID) is an effective detector for in vivo transit dosimetry. In fact, it supplies two-dimensional information, does not require special efforts to be used during patient treatment, and can supply data in real time. In the present paper, a new procedure has been proposed to improve the EPID in vivo dosimetry accuracy by taking into account the patient setup ...

Electronic portal imaging device (EPID) plays an important role in radiation therapy portal imaging, geometric and dosimetric verification. Consistent image quality and stable radiation response is necessary for proper utilization that requires routine quality assurance (QA). A commercial 'EPID QC' phantom weighing 3.8 kg with a dimension of 25 × 25 × 4.8 cm³ is used for EPID QA. This device ha...

Quality assurance (QA) of an intensity-modulated radiation therapy (IMRT) plan is more complex than that of a conventional plan. To improve the efficiency of QA, electronic portal imaging devices (EPIDs) can be used. The major objective of the present work was to use a commercial treatment planning system to model EPID response for the purpose of pre-treatment IMRT dose verification. Images wer...

BACKGROUND The reproducibility of patient setup for radiotherapy is based on various methods including external markers, X-rays with planar or computerized image acquisition, and, more recently, surface matching imaging. We analyzed the setup reproducibility of 16 patients affected by prostate cancer who underwent conformal radiotherapy with curative intent by using a surface image registration...