Traducció i immigració : la formació de traductors i intèrprets als serveis públics, noves solucions per a noves realitats

L'estudi que presentem té com a propòsit difondre els objectius, la metodologia i els principals resultats del projecte Traducció i immigració: la formació de traductors i intèrprets als serveis públics, noves solucions per a noves realitats, dut a terme pel grup MIRAS (Mediació i Interpretació: Recerca en l'Àmbit Social) entre els anys 2009 i 2010. L'objectiu general d'aquest projecte ha estat recopilar i analitzar un corpus significatiu de dades empíriques sobre la situació de la traducció i interpretació als serveis públics a Catalunya des de la perspectiva dels tres agents que participen en la interacció comunicativa: a) els mediadors-traductors-intèrprets, b) els usuaris dels serveis públics, i c) els proveïdors directes d'aquests serveis. Les dades obtingudes -tant quantitatives com qualitatives- ens han permès no tan sols definir el perfil i la pràctica professional del traductor i intèrpret als serveis públics de Catalunya, sinó també obtenir una gran quantitat d'informació objectiva sobre les necessitats i les preferències dels usuaris i proveïdors dels serveis públics: amb quin tipus de dificultats comunicatives se solen enfrontar, quin tipus de mediació prefereixen uns i altres, quines són les llengües estrangeres més requerides, quines particularitats presenta cada àmbit d'actuació, etc.The aim of the present study is to publish the principal objectives, methodology and results of the project Translation and Immigration: the training of public service translators and interpreters, new solutions for new scenarios. The overall objective of the project, which was carried out during the period 2009 -2010, was to assemble and analyze a significant corpus of empirical data on the situation of Public Service Interpreting and Translating in Catalonia from the perspective of the three agents participating in the communicative interaction: a) the mediator-translator-interpreter, b) the public services end-user and c) the front-line public services provider. From the data obtained -both quantitative and qualitative- we were able not only to define the professional profile and practice of the public services translator and interpreter in Catalonia, but also to obtain a large quantity of objective information about the needs and preferences of the endusers and providers of public services: what sort of difficulties do they encounter in their communication exchanges; what sort of mediation do the two groups prefer; which foreign languages are most in demand; what are the specific characteristics involved in each field of intervention, etc

2D EPID dosimetry for an MR-linac: proof of concept

Purpose: At our institute, in-vivo patient dose distributions are reconstructed for all treatments delivered using conventional linacs from Electronic Portal Imaging Device (EPID) transit images acquired during treatment using a simple back-projection model. Currently, the clinical implementation of MRI-guided radiotherapy systems, which aims for online and real-time adaptation of the treatment plan, is progressing. In our department the MR-linac (Unity, Elekta AB, Stockholm, Sweden) is now in clinical use. The aim of this work is to demonstrate the feasibility of 2D EPID dosimetric verification for the MR-linac by comparing back-projected EPID doses to ionization chamber (IC) array dose distributions. Materials and methods: Our conventional back projection algorithm was adapted for the MR-linac. The most important changes involve modeling of the attenuation by and scatter from the cryostat. The commissioning process involved the acquisition of square field EPID measurements using various phantom setups (varying SSD, phantom thickness and field size). Commissioning models were created for gantry 0, 90 and 180 degrees and verified by comparing EPID reconstructed 2D dose distributions to measurements made with the OCTAVIUS 1500 IC array (PTW, Freiburg, Germany) for 2 prostate and 1 rectum IMRT plans (25 beams total). The average of the γ parameters (y-mean and y-pass rate) and the dose difference at a reference point were reported. Due to their construction, the attenuation of couch, bridge and cryostat shows a much stronger dependence on gantry angle in the MR-linac compared to conventional linacs. We present a method to correct for these effects. This method is validated by dose reconstruction of the 25 IMRT beams recorded at a certain gantry angle using the model of another gantry angle, combined with the correction method. Results: For dose verification performed at a gantry angle identical to the commissioned model the average y-mean and y-pass rate values (3% global dose, 2 mm, 10% isodose) were 0.37 ± 0.07 and 98.1, 95% CI [98.1 ± 2.4], respectively. The average dose difference at the reference point was -0.5% ± 1.8%. Verification at gantry angles different from the commissioned model (i.e., using the gantry angle dependent correction) reported 0.39 ± 0.08 and 97.6, 95% CI [96.9, 98.3] average y-mean and y-pass rate values. The average dose difference at the reference point was: -0.1% ± 1.8%. of MRI-guided radiotherapy systems, which aims for online and real-time adaptation of the treatment plan, is progressing. In our department the MR-linac (Unity, Elekta AB, Stockholm, Sweden) is now in clinical use. The aim of this work is to demonstrate the feasibility of 2D EPID dosimetric verification for the MR-linac by comparing back-projected EPID doses to ionization chamber (IC) array dose distributions.Biological, physical and clinical aspects of cancer treatment with ionising radiatio

Two‐dimensional EPID dosimetry for an MR‐linac: Proof of concept

Purpose: At our institute, in-vivo patient dose distributions are reconstructed for all treatments delivered using conventional linacs from Electronic Portal Imaging Device (EPID) transit images acquired during treatment using a simple back-projection model. Currently, the clinical implementation of MRI-guided radiotherapy systems, which aims for online and real-time adaptation of the treatment plan, is progressing. In our department the MR-linac (Unity, Elekta AB, Stockholm, Sweden) is now in clinical use. The aim of this work is to demonstrate the feasibility of 2D EPID dosimetric verification for the MR-linac by comparing back-projected EPID doses to ionization chamber (IC) array dose distributions. Materials and methods: Our conventional back projection algorithm was adapted for the MR-linac. The most important changes involve modeling of the attenuation by and scatter from the cryostat. The commissioning process involved the acquisition of square field EPID measurements using various phantom setups (varying SSD, phantom thickness and field size). Commissioning models were created for gantry 0, 90 and 180 degrees and verified by comparing EPID reconstructed 2D dose distributions to measurements made with the OCTAVIUS 1500 IC array (PTW, Freiburg, Germany) for 2 prostate and 1 rectum IMRT plans (25 beams total). The average of the γ parameters (y-mean and y-pass rate) and the dose difference at a reference point were reported. Due to their construction, the attenuation of couch, bridge and cryostat shows a much stronger dependence on gantry angle in the MR-linac compared to conventional linacs. We present a method to correct for these effects. This method is validated by dose reconstruction of the 25 IMRT beams recorded at a certain gantry angle using the model of another gantry angle, combined with the correction method. Results: For dose verification performed at a gantry angle identical to the commissioned model the average y-mean and y-pass rate values (3% global dose, 2 mm, 10% isodose) were 0.37 ± 0.07 and 98.1, 95% CI [98.1 ± 2.4], respectively. The average dose difference at the reference point was -0.5% ± 1.8%. Verification at gantry angles different from the commissioned model (i.e., using the gantry angle dependent correction) reported 0.39 ± 0.08 and 97.6, 95% CI [96.9, 98.3] average y-mean and y-pass rate values. The average dose difference at the reference point was: -0.1% ± 1.8%. of MRI-guided radiotherapy systems, which aims for online and real-time adaptation of the treatment plan, is progressing. In our department the MR-linac (Unity, Elekta AB, Stockholm, Sweden) is now in clinical use. The aim of this work is to demonstrate the feasibility of 2D EPID dosimetric verification for the MR-linac by comparing back-projected EPID doses to ionization chamber (IC) array dose distributions.Biological, physical and clinical aspects of cancer treatment with ionising radiatio

Characterization of the a-Si EPID in the unity MR-linac for dosimetric applications

Abstract Electronic portal imaging devices (EPIDs) are frequently used in external beam radiation therapy for dose verification purposes. The aim of this study was to investigate the dose-response characteristics of the EPID in the Unity MR-linac (Elekta AB, Stockholm, Sweden) relevant for dosimetric applications under clinical conditions. EPID images and ionization chamber (IC) measurements were used to study the effects of the magnetic field, the scatter generated in the MR housing reaching the EPID, and inhomogeneous attenuation from the MR housing. Dose linearity and dose rate dependencies were also determined. The magnetic field strength at EPID level did not exceed 10 mT, and dose linearity and dose ratedependencies proved to be comparable to that on a conventional linac. Profiles of fields, delivered with and without the magnetic field, were indistinguishable. The EPID center had an offset of 5.6 cm in the longitudinal direction, compared to the beam central axis, meaning that large fields in this direction will partially fall outside the detector area and not be suitable for verification. Beam attenuation by the MRI scanner and the table is gantry angle dependent, presenting a minimum attenuation of 67% relative to the 90° measurement. Repeatability, observed over two months, was within 0.5% (1 SD). In order to use the EPID for dosimetric applications in the MR-linac, challenges related to theEPID position, scatter from the MR housing, and the inhomogeneous, gantry angle-dependent attenuation of the beam will need to be solved.Biological, physical and clinical aspects of cancer treatment with ionising radiatio

Automatic in vivo portal dosimetry of all treatments.

At our institution EPID (electronic portal imaging device) dosimetry is routinely applied to perform in vivo dose verification of all patient treatments with curative intent since January 2008. The major impediment of the method has been the amount of work required to produce and inspect the in vivo dosimetry reports (a time-consuming and labor-intensive process). In this paper we present an overview of the actions performed to implement an automated in vivo dosimetry solution clinically. We reimplemented the EPID dosimetry software and modified the acquisition software. Furthermore, we introduced new tools to periodically inspect the record-and-verify database and automatically run the EPID dosimetry software when needed. In 2012, 95% of our 3839 treatments scheduled for in vivo dosimetry were analyzed automatically (27,633 portal images of intensity-modulated radiotherapy (IMRT) fields, 5551 portal image data of VMAT arcs, and 2003 portal images of non-IMRT fields). The in vivo dosimetry verification results are available a few minutes after delivery and alerts are immediately raised when deviations outside tolerance levels are detected. After the clinical introduction of this automated solution, inspection of the detected deviations is the only remaining work. These newly developed tools are a major step forward towards full integration of in vivo EPID dosimetry in radiation oncology practic