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Cette étude prolonge un travail de recherche sur la signification des noms des parties du corps humain (Npc) (Bertin, 2018). On s'intéresse à la construction illustrée par Colin a le front de venir à cette réunion (NPV). Après un inventaire des Npccompatibles avec NPV, on procède à une analyse sémantique : d'une part, on cerne le sens de NPV (en se focalisant sur la contribution du Npc) et, d'autre part, on tire profit de cette première étape pour l'analyse sémantique des Npceux-mêmes.

Chlordecone (CLD) is a Persistent Organic Pollutant used between 1972 until 1993 in the French West Indies (FWI). Due to its persistence and extensive application, a quarter of the total local agricultural acreage is still moderate to heavily polluted. In consequence, livestock may be contaminated at various levels. This is a major public health concern, particularly for local consumers. In order to better understand the fate of CLD in livestock organisms, in vivo studies are required. There is no information available about its metabolism and elimination in ruminants, common livestock in the FWI. To be able to monitor the fate of chlordecone and its metabolites in livestock and to assess if the compounds could be released in the environment, urinary and fecal samples were logically targeted. In order to reach this goal, robust and validated analytical methods are required. For this purpose, Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) extraction methods were validated to analyze CLD and its metabolites in the urine and feces. The analysis was carried using liquid phase chromatography with tandem mass spectrometry and validated according to French standard NF V03-110 and SANTE guidelines. Matrix effect, Accuracy, within-laboratory repeatability, specificity, Q/q relative ion intensities and uncertainty were reported. Recoveries between 70% and 120% were obtained from urine and feces. The limits of quantification (LOQ) in urine samples were 0.1 μg CLD L−1, 0.1 μg total CLD (CLD and its conjugates)·L−1, 1.3 μg CLDOH L−1 and 2.4 μg total CLD (chlordecol and its conjugates) L−1 of urine. LOQ in fresh feces were 3.2 μg CLD kg−1 and 5.8 μg CLDOH kg−1. Contaminated urinary and fecal samples from ewes were analyzed to confirm the relevance of the methods. In urine, CLD and conjugated CLDOH could be quantified whereas only free CLD and free CLDOH were found in feces. These methods are essential for future toxicokinetic studies and also to estimate the environmental contamination.

Background The dentitions of extinct organisms can provide pivotal information regarding their phylogenetic position, as well as paleobiology, diet, development, and growth. Extant birds are edentulous (toothless), but their closest relatives among stem birds, the Cretaceous Hesperornithiformes and Ichthyornithiformes, retained teeth. Despite their significant phylogenetic position immediately outside the avian crown group, the dentitions of these taxa have never been studied in detail. To obtain new insight into the biology of these ‘last’ toothed birds, we use cutting-edge visualisation techniques to describe their dentitions at unprecedented levels of detail, in particular propagation phase contrast x-ray synchrotron microtomography at high-resolution. Results Among other characteristics of tooth shape, growth, attachment, implantation, replacement, and dental tissue microstructures, revealed by these analyses, we find that tooth morphology and ornamentation differ greatly between the Hesperornithiformes and Ichthyornithiformes. We also highlight the first Old World, and youngest record of the major Mesozoic clade Ichthyornithiformes. Both taxa exhibit extremely thin and simple enamel. The extension rate of Hesperornis tooth dentine appears relatively high compared to non-avian dinosaurs. Root attachment is found for the first time to be fully thecodont via gomphosis in both taxa, but in Hesperornis secondary evolution led to teeth implantation in a groove, at least locally without a periodontal ligament. Dental replacement is shown to be lingual via a resorption pit in the root, in both taxa. Conclusions Our results allow comparison with other archosaurs and also mammals, with implications regarding dental character evolution across amniotes. Some dental features of the ‘last’ toothed birds can be interpreted as functional adaptations related to diet and mode of predation, while others appear to be products of their peculiar phylogenetic heritage. The autapomorphic Hesperornis groove might have favoured firmer root attachment. These observations highlight complexity in the evolutionary history of tooth reduction in the avian lineage and also clarify alleged avian dental characteristics in the frame of a long-standing debate on bird origins. Finally, new hypotheses emerge that will possibly be tested by further analyses of avian teeth, for instance regarding dental replacement rates, or simplification and thinning of enamel throughout the course of early avian evolution. Electronic supplementary material The online version of this article (doi:10.1186/s12862-016-0753-6) contains supplementary material, which is available to authorized users.