| 1. |
- Akkurt, I, et al.
(författare)
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Photoneutron yields from tungsten in the energy range of the giant dipole resonance
- 2003
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Ingår i: Physics in Medicine and Biology. - : IOP Publishing. - 1361-6560 .- 0031-9155. ; 48:20, s. 3345-3352
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Tidskriftsartikel (refereegranskat)abstract
- Photoneutron production on the nuclei of high-Z components of medical accelerator heads can lead to a significant secondary dose during a course of bremsstrahlung radiotherapy, However, a quantitative evaluation of secondary neutron dose requires improved data on the photoreaction yields. These have been measured as a function of photon energy, neutron energy and neutron angle for W-nat, using tagged photons at the MAX-Lab photonuclear facility in Sweden. This work presents neutron yields for W-nat(gamma, n) and compares these with the predictions of the Monte Carlo code MCNP-GN, developed specifically to simulate photoneutron production at medical accelerators.
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| 2. |
- Gallucci, M, et al.
(författare)
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Factors related to disability: Evidence from the "Treviso Longeva (TRELONG) Study"
- 2010
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Ingår i: Archives of gerontology and geriatrics. - : Elsevier BV. - 1872-6976 .- 0167-4943. ; 52:3, s. 309-16
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Tidskriftsartikel (refereegranskat)abstract
- Prolongation of life is an important public health goal as long as there is an emphasis on the quality of life (QoL) and independent living. Diminishing abilities to ambulate and participate in activities of daily living point to a serious decline in functional health, increasing the risk of institutionalization and death. In our work we found a pattern of factors associated with disability, especially cognitive impairment, as well as stroke, physical activity and performance, reading, and the nutritional biomarkers, blood albumin and high-density lipoprotein cholesterol (HDL-C). The attention to this cluster of markers, suggesting multidimensional prevention, may have unexpected good effects against disability.
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| 3. |
- Zanini, A, et al.
(författare)
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Monte Carlo simulation of the photoneutron field in linac radiotherapy treatments with different collimation systems
- 2004
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Ingår i: Physics in Medicine and Biology. - : IOP Publishing. - 1361-6560 .- 0031-9155. ; 49:4, s. 571-582
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Tidskriftsartikel (refereegranskat)abstract
- Bremsstrahlung photon beams produced by linac accelerators are currently the most commonly used method of radiotherapy for tumour treatments. When the photon energy exceeds 10 MeV the patient receives an undesired dose due to photoneutron production in the accelerator head. In the last few decades, new sophisticated techniques such as multileaf collimators have been used for a better definition of the target volume. In this case it is crucial to evaluate the photoneutron dose produced after giant dipole resonance (GDR) excitation of the high Z materials (mainly tungsten and lead) constituting the collimator leaves in view of the optimization of the radiotherapy treatment. A Monte Carlo approach has been used to calculate,the photoneutron dose arising from the GDR reaction during radiotherapy with energetic photon beams. The simulation has been performed using the code MCNP4B-GN which is based on MCNP4B, but includes a new routine GAMMAN to model photoneutron production. Results for the facility at IRCC (Istituto per la Ricerca e la Cura del Cancro) Candiolo (Turin), which is based on 18 MV x-rays from a Varian Clinac 2300 C/D, are presented for a variety of different collimator configurations.
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