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Acceptation du recours à l'interruption volontaire de grossesse chez les Français de 18–24 ans en 2021
No full textInternational audienc
Morpho-sedimentary characteristics of Holocene paleochannels in the Upper Rhine alluvial plain, France
No full textInternational audienceThe French Upper Rhine alluvial plain is characterized by a complex system of paleochannels inherited from Late Glacial to Holocene fluvial dynamics of the Rhine and Ill river systems, among other smaller rivers. These paleochannels represent valuable archives for understanding and reconstructing the fluvial and landscape evolution of the area. However, the Holocene temporal trajectories of the paleochannels, in response to a range of environmental changes, remain poorly understood. This study presents a detailed and systematic mapping and characterization of an extensive network of paleochannels spanning the entire width (19 km) of a reach of the central French Rhine plain. Based on qualitative and quantitative lidar analysis, field investigations, and provenance investigations of paleochannel infill sequences, five distinct paleochannel groups (PG 1 to PG 5) were identified in the study area. These paleochannel groups differ considerably regarding their channel patterns, morphological characteristics, and sedimentary sources of the infilling sediments. The interpretation of the different datasets indicates that the development of these different paleomorphologies is attributed to significant changes in hydro-geomorphodynamic processes in the area during the Holocene, especially lateral migrations of the Rhine and Ill rivers. The findings reported here are promising and will have significant implications for reconstructing the long-term (Late Glacial to Holocene) evolution of the Upper Rhine fluvial hydrosystem in response to various controlling factors
Combined effects of nitric oxide synthase 3 genetic variant and childhood emotional abuse on earlier onset of suicidal behaviours
No full textInternational audienceMarked heterogeneity in suicide attempters has been observed, with earlier onset being linked to stronger heritability, more childhood maltreatment. Nitric oxide signalling system might be implicated in this relationship through its role in the stress response/adaptation. This study examined how NOS genetic variants and childhood maltreatment were associated with age at first suicide attempt (SA). Adult patients with SA history (N = 414) filled in the Childhood Trauma Questionnaire, and six functionally relevant NOS2 and NOS3 polymorphisms were genotyped. Analyses included χ2, Mann-Whitney U tests, Kendall's regression, multivariate linear and Cox survival regressions, and a moderation analysis. The NOS3 promotor 27-bp variable number tandem repeat (VNTR) bb homozygous state and childhood emotional abuse were independently associated with earlier age at first SA, which was robust after controlling for confounders [regression coefficient - 3.975, 95% CI -6.980 - (-0.970), p = 0.010, and - 1.088, 95% CI -2.172 - (-0.004), p = 0.049]. No interaction was observed. In the Cox proportional hazards model for age at first SA, the hazard ratio for patients with childhood emotional abuse and NOS3 27-bp VNTR bb was 0.533 (95% CI 0.394-0.720, p < 0.001) compared to patients without. Intermediate scores were observed with either only the risk genotype or only childhood emotional abuse. A graded relationship was also observed for repeated SA, family history of SA, and severe SA history. These results are preliminary due to a low statistical power and call for replication and further characterization of the role of nitric oxide system in the susceptibility to early-onset SB
Thallium Pollution in Europe Over the Twentieth Century Recorded in Alpine Ice: Contributions From Coal Burning and Cement Production
No full textInternational audienceEmission inventories indicate that thallium, a highly toxic metal, is emitted during coal burning and cement production. These estimates have been established only for the 1980s and 1990s but up to now they have not been compared to long-term observations. Here we used alpine ice cores to document thallium pollution over Europe since ∼1850. Ice-core thallium concentrations increased from 1890 to 1910, and decreased after 1965 to concentrations that were half 1890 levels. Comparison of ice-core trends, estimated past emissions, and state-of-the-art atmospheric aerosol transport modeling suggest that coal burning was responsible for thallium pollution in Europe, particularly from 1920 to 1965 because of high coal consumption at that time. The subsequent decline resulted from decreased coal consumption and reduced emissions following technological improvements. The ice-core data suggest that the rapid growth of cement production that took place in Europe after 1950 had a limited impact on thallium pollution
Expression Patterns of Drosophila Melanogaster Glutathione Transferases
No full textThis article belongs to the Section Insect Molecular Biology and Genomics.International audienceGlutathione transferases (GSTs) are ubiquitous enzymes that catalyze the conjugation of glutathione to various molecules. Among the 42 GSTs identified in Drosophila melanogaster, Delta and Epsilon are the largest classes, with 25 members. The Delta and Epsilon classes are involved in different functions, such as insecticide resistance and ecdysone biosynthesis. The insect GST number variability is due mainly to these classes. Thus, they are generally considered supports during the evolution for the adaptability of the insect species. To explore the link between Delta and Epsilon GST and their evolution, we analyzed the sequences using bioinformatic tools. Subgroups appear within the Delta and Epsilon GSTs with different levels of diversification. The diversification also appears in the sequences showing differences in the active site. Additionally, amino acids essential for structural stability or dimerization appear conserved in all GSTs. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis revealed that the transcripts corresponding to these two classes are heterogeneously expressed within D. melanogaster. Some GSTs, such as GSTD1, are highly expressed in all tissues, suggesting their general function in detoxification. Conversely, some others, such as GSTD11 or GSTE4, are specifically expressed at a high level specifically in antennae, suggesting a potential role in olfaction
Corrigendum to "Exposure of the population of southern France to air pollutants in future climate case studies" [Atmos. Environ. 234 (2021) 118689]
No full textInternational audienceThe authors regret the wrong highlights were published for the paper. The corrected highlight section should be: •Several future test cases have been explored for the south-eastern Mediterranean coasts of France
Quels livres pour apprendre à lire ? Les logiques d’un répertoire au cours préparatoire
No full textInternational audience131 primary school teachers were surveyed three times during school year 2013-2014 on the picture books read in class during the two previous weeks. The book list obtained – titles, writers and publishers - shows what types (narrative, expository…) and genres (traditional tales, poetry, etc.) teachers prefer, as well as the extent to which they use books prescribed by the national curriculum or which form part of a specific reading programme. This list raises the issue of what influences teachers’ choices, revealing multiple influences, from curricular prescriptions, publishers’ policies, and beyond these, from the notion of what “legitimate” children’s literature should be. It also shows how choices are, above all, determined by learning objectives, such as word identification and text comprehension.Une enquête a été réalisée auprès de 131 enseignants de cours préparatoire sur les livres lus par les élèves ou aux élèves en classe dans le cadre de la recherche Lire-écrire au CP conduite en 2013-2014. Elle permet d’établir le répertoire des lectures – titres, auteurs, éditeurs – et de donner les caractéristiques de celui-ci – types, genres, caractère patrimonial, appartenance éventuelle aux listes de prescriptions, à un manuel. Est posée ensuite la question des logiques qui président à sa constitution, en mobilisant les notions de culture scolaire et de littératie. Sont ainsi mises en évidence des influences multiples (listes officielles, éditeurs et, de manière plus diffuse, conception de ce qu’est une littérature de jeunesse légitime), mais surtout le poids des exigences liées aux objectifs de l’apprentissage de la lecture au cours préparatoire : apprendre à déchiffrer et apprendre à comprendre les textes
Extensions of derivations and symmetric operators
No full textGiven a densely defined skew-symmetric operators A 0 on a real or complex Hilbert space V , we parametrize all m-dissipative extensions in terms of contractions Φ : H-→ H + , where Hand H + are Hilbert spaces associated with a boundary quadruple. Such an extension generates a unitary C 0-group if and only if Φ is a unitary operator. As corollary we obtain the parametrization of all selfadjoint extensions of a symmetric operator by unitary operators from Hto H +. Our results extend the theory of boundary triples initiated by von Neumann and developed by V. I. and M. L. Gorbachuk, J. Behrndt and M. Langer, S. A. Wegner and many others, in the sense that a boundary quadruple always exists (even if the defect indices are different in the symmetric case)
Modal Analysis of the Ancillary During Femoral Stem Insertion: A Study on Bone Mimicking Phantoms
No full textInternational audienceThe femoral stem primary stability achieved by the impaction of an ancillary during its insertion is an important factor of success in cementless surgery. However, surgeons still rely on their proprioception, making the process highly subjective. The use of Experimental Modal Analysis (EMA) without sensor nor probe fixation on the implant or on the bone is a promising non destructive approach to determine the femoral stem stability. The aim of this study is to investigate whether EMA performed directly on the ancillary could be used to monitor the femoral stem insertion into the bone. To do so, a cementless femoral stem was inserted into 10 bone phantoms of human femurs and EMA was carried out on the ancillary using a dedicated impact hammer for each insertion step. Two bending modes could be identified in the frequency range [400–8000] Hz for which the resonance frequency was shown to be sensitive to the insertion step and to the bone-implant interface properties. A significant correlation was obtained between the two modal frequencies and the implant insertion depth (R2 = 0.95 ± 0.04 and R2 = 0.94 ± 0.06). This study opens new paths towards the development of noninvasive vibration based evaluation methods to monitor cementless implant insertion