Use of IAEA's phase-space files for virtual source model implementation: Extension to large fields.

In a previous work, phase-space data files (phsp) provided by the International Atomic Energy Agency (IAEA) were used to develop a hybrid virtual source model (VSM) for clinical photon beams. Very good agreement with dosimetric measurements performed on linear accelerators was obtained for field sizes up to 15×15cm(2). In the present work we extend the VSM to larger field sizes, for which phsp are not available.

Use of IAEA's phase-space files for the implementation of a clinical accelerator virtual source model.

In the present work, phase-space data files (phsp) provided by the International Atomic Energy Agency (IAEA) for different accelerators were used in order to develop a Virtual Source Model (VSM) for clinical photon beams. Spectral energy distributions extracted from supplied phsp files were used to define the radiation pattern of a virtual extended source in a hybrid model which is completed with a virtual diaphragm used to simulate both electron contamination and the shape of the penumbra region. This simple virtual model was used as the radiation source for dosimetry calculations in a water phantom.

Radioluminescence of red-emitting Eu-doped phosphors for fiberoptic dosimetry.

Fiberoptic dosimetry (FOD) technique has become an attractive method for real-time dosimetry. Al(2)O(3):Cis one of the most used radioluminescence materials for FOD due to its high efficiency but it presents the drawback of emitting in the spectral region, where spurious luminescence is also important. Optical filtering is the simplest technique to remove spurious luminescence, but is useful when red-emitting scintillators are employed.

Effects of static magnetic fields on nicotinic cholinergic receptor function.

Ligand-gated ion channel kinetics were studied in mammalian transfected cells encoding adult mouse muscle acetylcholine (ACh) receptors. We measured macroscopic and single-channel currents using the outside-out and cell-attached patch-clamp configurations. Cultured cells were exposed to moderate intensity inhomogeneous static magnetic fields up to 180 mT and measurements were performed for temperatures ranging from 5 to 50 °C.

A modified simulated annealing algorithm for parameter determination for a hybrid virtual model.

In this work we present an algorithm based on the simulated annealing (SA) method for electron beam spectrum reconstruction from central axis PDD data. We use a simulated beam in order to assess the accuracy of the method, and compare it with others usually employed. We found that our modified SA algorithm produced excellent reconstructed PDDs and beam profiles and improved reconstructed spectra.