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Excavated between 2005 and 2007, the site of Vallparadís (Terrassa, Spain) has given an abundant and diversified fauna associated with a rich Mode 1 industry. In order to complete the chronostratigraphic framework, we performed ESR and combined US-ESR dating applied to quartz grains extracted from sediments and fossil teeth, respectively. The results obtained are very significant, giving a weighted mean ESR age of 0.83 ± 0.13 Ma (2σ) for the reference archaeological level of the site (level 10) and another of 0.79 ± 0.23 Ma (2σ) for the archaeological level 12 of the Vallparadís sequence. These ESR results are in total agreement with the ones derived from biochronology and paleomagnetism. This whole dataset allows the elaboration of a reliable and consistent chronostratigraphic framework which chronologically places Vallparadís site in the late Early Pleistocene period, i.e. within a time range comprised between Jaramillo and Brunhes geomagnetic events. Consequently, as well as Gran Dolina-TD6 and Sima del Elefante- TE9 sites, in Atapuerca, Burgos, Vallparadís can be therefore considered as a key site for the study of early hominid settlements in Europe., Excavado entre 2005 y 2007, el yacimiento de Vallparadís (Terrassa, España) ha aportado una fauna rica y diversa en asociación con un importante conjunto lítico de Modo 1. Con el objetivo de completar el marco cronoestratigráfico, se hicieron dataciones por los métodos de Resonancia Paramagnética Electrónica (Electron Spin Resonance, ESR) y ESR combinada con uranio-torio sobre algunas muestras de granos de cuarzo extraídos de sedimentos y dientes fósiles, respectivamente. Los resultados obtenidos son muy significativos, ofreciendo edades ESR promedias de 0,83 ± 0,13 Ma (2σ) para el nivel arqueológico de referencia del yacimiento (nivel 10) y de 0,79 ± 0,23 Ma (2σ) para el nivel arqueológico 12 de la secuencia de Vallparadís. Dichos resultados por ESR concuerdan con los obtenidos a partir de la biocronología y del paleomagnetismo. El yacimiento de Vallparadís dispone ahora de un marco cronoestratigráfico fiable y coherente, que permite situarlo cronológicamente a finales del Pleistoceno inferior, dentro de un rango temporal comprendido entre los eventos geomagnéticos de Jaramillo y Brunhes. Dicho yacimiento junto a los de Gran Dolina TD-6 y Sima del Elefante TE-9, en Atapuerca, Burgos, se posiciona como un yacimiento clave para el estudio de los primeros poblamientos humanos de Europa.

International audience; Purpose:Elekta Leksell Gamma Knife® (LGK) is a radiotherapy beam machine whose features are not compliant with the international calibration protocols for radiotherapy. In this scope, the Laboratoire National Henri Becquerel and the Pitié‐Salpêtrière Hospital decided to conceive a new LKG dose calibration method and to compare it with the currently used one. Furthermore, the accuracy of the dose delivered by the LGK machine was checked using an “end‐to‐end” test. This study also aims to compare doses delivered by the two latest software versions of the Gammaplan treatment planning system (TPS).Methods:The dosimetric method chosen is the electron paramagnetic resonance (EPR) of alanine. Dose rate (calibration) verification was done without TPS using a spherical phantom. Absolute calibration was done with factors calculated by Monte Carlo simulation (MCNP‐X). For “end‐to‐end” test, irradiations in an anthropomorphic head phantom, close to real treatment conditions, are done using the TPS in order to verify the delivered dose.Results:The comparison of the currently used calibration method with the new one revealed a deviation of +0.8% between the dose rates measured by ion chamber and EPR/alanine. For simple fields configuration (less than 16 mm diameter), the “end‐to‐end” tests showed out average deviations of −1.7% and −0.9% between the measured dose and the calculated dose by Gammaplan v9 and v10, respectively.Conclusions:This paper shows there is a good agreement between the new calibration method and the currently used one. There is also a good agreement between the calculated and delivered doses especially for Gammaplan v10.

L’aven de Romain-la-Roche est l’un des sites paléontologiques majeurs de l’est de la France pour le Pléistocène. Le site, qui correspond au comblement d’une fissure de 7 m de large sur 11 m de haut s’ouvrant dans un substrat calcaire jurassique, a servi de piège naturel pour les grands mammifères et d’abri aux hommes préhistoriques dont la présence est attestée par la découverte de pièces lithiques moustériennes. Fouillé dans les années 1980, le gisement a livré plus de 25000 restes paléontologiques correspondant à une faune variée de grands mammifères, de micro-vertébrés et de mollusques. Une première étude chronologique, réalisée dans les années 1990 par uranium-thorium sur ossements, avait permis de proposer un âge rissien pour le gisement. Cependant, l’un des ossements analysés ayant fonctionné comme un système ouvert vis-à-vis de l’uranium, cette attribution chronologique nécessitait d’être vérifiée. Une nouvelle campagne de datation a donc été entreprise de 2007 à 2010 par la méthode de la résonance de spin électronique combinée à la méthode uranium-thorium (ESR/U-Th). Plusieurs dents issues des collections et provenant des principales couches paléontologiques du remplissage ont ainsi été analysées. Les données isotopiques U-Th de ces échantillons sont, à quelques exceptions près, relativement homogènes et semblent indiquer qu’ils ont tous évolué de façon similaire depuis leur enfouissement. Les résultats de cette étude permettent de dater la partie inférieure du remplissage (couches VI-VII, VIII et IX) de la dernière partie du Riss (stade isotopique 6). Par contre, le niveau supérieur (couche V) a livré des âges incohérents par rapport à la stratigraphie du site et des résultats obtenus pour les niveaux sous-jacents, qui pourraient être expliqués par des phénomènes de migration des éléments radioactifs ou d’une chauffe archéologique éventuelle des ossements. The Romain-la-Roche aven is one of the main palaeontological sites of eastern France for the Pleistocene period. The site, which corresponds to the infilling of a fissure opening into a Jurassic limestone, has acted as a natural trap for great mammals and as a shelter for prehistoric men, as attested by the discovery of Mousterian artefacts. Excavated during the 1980’s, the site has delivered more than 25,000 palaeontological remains corresponding to a diversified fauna including great mammals, micro-vertebrates and molluscs. A previous chronological study, realised during the 1990’s using uranium-series method (U-series) on bones, has allowed the proposal of a Riss age for the site. However, one of the analyzed bones has acted as an open system for uranium migration and its chronological attribution should be verified. A new dating program was therefore performed from 2007 to 2010 combining electron spin resonance and U-series methods (US-ESR). Several teeth selected from collections and issued from the main paleontological layers of the infilling have then been analyzed. Results permit to date the lower part of the sequence (layers VI-VII, VIII and IX) from the last part of the Riss stage (marine isotope stage 6). On the other hand, the upper level (layer V) has not been dated because of probable radioactive element migration.