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Au fur et a mesure que les chercheurs repoussent les limites du savoir sur la nano science, les nanomateriaux occupent une place de plus en plus importante dans les applications de tous les jours. Les nanoparticules d’oxyde de magnesium se demarquent par leur stabilite chimique, thermique, electrique, optique et leur compatibilite avec l’environnement sous certaines conditions. Un exemple d’application des nanoparticules de MgO est leur utilisation dans la decontamination des eaux usees des colorants textiles et la depollution de l’air en enlevant le CO2. Il a ete observe que les nanoparticules de MgO ont une grande affinite a capturer les ions OH- et le CO2. La spectroscopie Raman, quant a elle, est une technique versatile, non destructible (c’est-a-dire qui ne detruit pas l’echantillon) et relativement …

The notion of transparency regularly comes up in discussions about the secondary uses of health data. Few studies, however, examine the impact of the presence or absence of transparency on members of the public. This literature review responds to this gap in the scientific literature. It is the result of a secondary analysis of 124 texts from an exploratory review on transparency, following the PRISMAS-ScR guidelines. The results help to identify negative or positive impacts and associate these with certain communication components relating to secondary uses of health data. They also make it possible to identify the components associated with communication deemed transparent or opaque by stakeholders. Transparency, and more specifically continuity of communication, is strongly associated with increased trust and social acceptability, whereas members of the public generally perceive a lack of transparency negatively. This literature review also deepens our understanding of the potential negative impacts of transparent communication.

Keywords: impacts, transparence, données de santé, utilisations secondaires, systèmes de santé apprenants, impacts, transparency, health data, secondary uses, learning health systems

A total of 312 Neolithic causewayed enclosures were referenced in 2020 between the rivers Loire and Dor-dogne in Central-Western France. Most of these enclosures were discovered using aerial photography, which highlight the cropmarks of the enclosure ditches, taken by prospectors or by State services such as the IGN. Since the 2010s, in addition to aerial survey, geomagnetic surveys are increasingly used to map these enclosed sites. Geomagnetic surveying offers a complementary approach, which enables the detection of small entrance features, palisades and postholes rarely visible in the cropmarks seen on aerial photos. The number of geomagnetic surveys of Neolithic enclo-sures has considerably increased thanks to the ANR MONUMEN with the survey of more than eighteen sites between the end of 2018 and the beginning of 2020. These new surveys have led us to qualify and quantify how geomagnetic survey has contributed to the study of these enclosures and to determine its complementarity in relation to aerial survey. The local geology influences the quality of aerial photos, as the appearance of cropmarks is conditioned by water stress. The latter is more or less important depending on the water retention capacity of the soil and thus depends on the nature of the soil and the bedrock. Cropmark visibility varies depending on the local bedrock and the restitution of the archi- tecture of the enclosure is more or less reliable. It was possible to quantify the loss of information by comparing aerial photos to the geomagnetic survey. Aerial images of enclosures located on a limestone substrate have an information loss of less than 33% compared to magnetic anomaly maps. On this type of bedrock, aerial photography is relevant and the cropmarks of the ditches can be superimposed on the geomagnetic survey. On the other hand, aerial photographs of enclosures located on a marly bedrock lose about 66 % of information compared to the magnetic anomaly maps. On this type of substratum, aerial photography is less relevant and part of the enclosure is not visible on the pictures. A comparison of the enclosure architecture seen on the aerial photographs with that seen on the magnetic anomaly maps is also relevant. The enclosure of the Coteaux de Coursac at Balzac (Charente) is a site where the cropmarks of the ditches are visible only under certain conditions (hydric stress). The quality of the aerial images is excellent and highlights numerous causewayed structures (discontinuous ditches, fences, postholes). However, the aerial imagery does not match the magnetic anomaly map, which is more precise in its mapping of smaller causewayed features (palisades, postholes). Moreover, the variations of magnetization contrasts within the ditches are an indication of the variations of their fill. Aerial imagery is certainly relevant for mapping the architecture of an enclosure but is not has detailed as the geomagnetic survey. When comparing the quality and quantity of the detail visible between the magnetic anomaly maps and the aerial images, magnetic anomaly maps are able to detect small causewayed features such as entrances, palisades and pos-tholes. Several examples are presented here including the sites of le Pontet at Saint-Nazaire-sur-Charente (Charente-Maritime), la Vieille Garenne at Courcôme (Charente), le Peu at Charmé (Charente) and le Perradet at Saint-Groux (Charente). These small features are rarely visible on aerial photos. Some features have thermo-remanent magnetiza-tion from fire action, which can be detected by geomagnetic survey. This is the case at the site of le Peu at Charmé (Charente), where the postholes inside the enclosure mark to several burnt buildings. The fills of the postholes are thermo-remanent magnetized and are visible on the magnetic anomaly map. These postholes are however not visible on the aerial photographs. The dynamics of the magnetic signal or the magnetization contrast of the ditches of the Neolithic enclosures is not homogeneous and these variations reflect material heterogeneities in the ditch fill. These variations and their link to the magnetic signal were studied in the paper by Ard et al (2015) on the Bellevue enclosure at Chenommet (Charente). They are not generally visible on aerial photographs, but can in rare cases be detected on aerial photographs, notably at the site of Bellevue at Chenommet (Charente). To conclude, aerial and geomagnetic survey are complementary methods for the study of the architecture of Neolithic causewayed enclosures. Most sites are discovered by aerial survey, which is the primary source of information for mapping the ditches. These plans are based on the survey of ditch cropmarks, the appearance of which is governed by numerous factors making them difficult to predict from one year to another. Moreover, depending on the geological bedrock, the cropmarks are not always clearly identifiable and do not allow the entire architecture of the enclosure to be perceived. Finally, aerial photos are mostly shot at an oblique angle, which distorts distances and lengths. Orthorec-tification can alleviate this problem but is rarely used by volunteer prospectors. Magnetic prospecting allows the cau-sewayed structures of these sites to be mapped with better resolution and accuracy.

Keywords: Centre-West of France., Neolithic, causewayed enclosure, geomagnetic prospection, aerial photography, cropmark, Néolithique, enceinte fossoyée, prospection géomagnétique, photographie aérienne, indice phytologique, Centre-Ouest de la France.

The excavation of the surroundings of the cathedral at Tours allowed the study of some 1 000 m2 of a scarcely known sector situated less than 100 m from the late roman walled town. The data from this site gives precise indications about the evolution and the state of preservation of archaeological deposits in this area. The in-depth study of a street and part of a residential quarter has appreciably increased our knowledge of the roman period. This excavation also allows us to broach the subject of the transition of the late roman period and to have a more solid understanding of the early medieval suburbium.

This article is a methodological exemplification of the LMS method (Latent Moderated Structural Equations) available in Mplus. Data collected to study teenagers' motivation (n = 434) in physical education will serve to introduce a methodology to assess the interaction of latent variables in structural equation models. The following article focuses on the general understanding of the reader relative to the application of this method as well as on the presentation and interpretation of results. In closing, the benefits of the LMS method are put forward and new methodological exemplification is proposed.

Keywords: interaction, variable latente, méthodologie, modèle d'équations structurelles, éducation physique, interaction, latent variable, methodology, structural equation models, physical education, interacción, variable latente, metodología, modelo de ecuaciones estructurales, educación física