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B SEA, une plateforme pluridisciplinaire de formation à la transition éco-énergetique des industries de la mer
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What are the ethical considerations when supporting single women undergoing medically assisted reproduction (MAR) ?
No full textInternational audienceBackgroundSince the revision of French bioethics laws in 2021, requests for medically assisted reproduction (MAR) from single women have increased significantly. Specific challenges are faced by CECOS (Centre d'Étude et de Conservation des Ovocytes et du Sperme humain).PurposeThis article questions the ethical aspects of current support for single women undergoing MAR and motherhood.MethodsHere, we analyze single motherhood through the lens of the founding principles of medical ethics: respect for beneficence, non-maleficence, autonomy and justice.FindingsThe decision of a ‘single’ woman to start a family through MAR, without a partner (which does not mean that she is isolated or lonely) as being on the margins of dominant social family norms. Concerns may be expressed about the absence of a second parent and may sometimes mask value judgements on the part of relatives and healthcare professionals.ConclusionsIt is important to support all types of motherhood by consolidating services dedicated to maternal and child health
Frequency-Dependent Diffusion-Relaxation Distribution MRI: Scan-Rescan Reproducibility Ex Vivo and Caveats
No full textInternational audienceFrequency-dependent diffusion-relaxation distribution MRI provides information beyond the traditional voxel-averaged metric that may better characterize the microstructural features of biological tissue. Frequency-dependent multidimensional ( ω MD) MRI reproducibility has been established in clinical settings, but has yet to be thoroughly evaluated under preclinical conditions, where superior hardware and modulated gradient waveforms enhance its performance. In this study, we investigate the reproducibility of ω MD-MRI using a micro-imaging system to investigate ex vivo mouse brains. Notably, the estimated signal fractions of intra-voxel spectral components in the ω MD-MRI distribution, corresponding to white and gray matter, along with the frequency-dependent parameters, demonstrated high reproducibility. We identified bias between scan and rescan in some of the metrics, which we attribute to the time gap between repeated scans pointing to a long-time progressive fixation effect. We compare our results with in vivo results from clinical scanners and show the reproducibility of diffusion frequency-dependent metrics to benefit from the improved gradient hardware on our preclinical setup. Our results inform future micro-imaging ex vivo studies of the reproducibility of ω MD-MRI metrics and their dependence on fixation time
Proposition d’un modèle précurseur pour une compréhension du cycle de la matière organique lors de la pratique du compostage à l’école maternelle
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Profil d’une séance orientée investigation : impact d’un résultat de recherche sur la réflexion d’une enseignante
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Element mobilities during serpentinization: Insights from the Ronda Massif, Spain
No full textInternational audienceSerpentinization is a widespread hydrothermal alteration of ultramafic rocks, particularly peridotites, resulting in the formation of serpentinite through hydration processes. While the behavior of fluid-mobile elements (FME; e.g. B, Li, Cl, As, Sb, Pb, U, Th, Cs, Sr, Ba) during serpentinization is well documented, the mobility of other elements (e.g., base metals) remains poorly constrained. We analyzed bulk rock compositions of pairs of poorly and highly serpentinized peridotite rocks from the Ronda Massif (Spain), complemented by in situ LA-ICP-MS mineral analyses. The loss on ignition (LOI) content of whole rock represents a good proxy for serpentinization intensity. Ca, Al, Cu, V, and Ti are increasingly mobilized during the initial stages of pervasive serpentinization. In a second stage corresponding to total serpentinization along cm-wide, several meters-long corridors, a systematic loss in Ca, Al, Rb, Sr, REE Hf, Ti, Cu, and V was observed. In contrast, during the third stage of serpentinization corresponding to late faulting only Ca and Cu were leached. The trace element composition of J o u r n a l P r e -p r o o fJournal Pre-proof serpentine minerals, including Ti, V, and Zn, is influenced by the primary mineral assemblage, particularly olivine and pyroxenes. In contrast, the mobility of Al and Ca from millimeter to meter scale is notably linked to the bastite-pyroxene and serpentine mesh texture-olivine transformation. Co, Ni, Zn, and Cr depletion in serpentine within veins is compensated by their significant incorporation into magnetite. Copper is systematically leached from serpentinized rocks, suggesting that serpentinization likely serves as a significant source for Cu-rich hydrothermal metallogenic systems hosted in ultramafic rocks</div
First Ga<sub>2</sub>Se<sub>3</sub> infrared transparent chalcogenide ceramics
No full textInternational audienceFully dense infrared (IR) transparent chalcogenide ceramics were obtained from densification of Ga2Se3 crystalline powder by Spark Plasma Sintering (SPS) under vacuum. Promising results were attained such as a maximum transmission of 63 % at lambda = 11 mu m, close to the maximum value of transmittance previously measured for single crystals, a wide transparency spectral range (4-16 µm), and a refractive index of 2.58 at lambda = 1.55 µm. Electron Back Scattered Diffraction (EBSD) was used to elucidate grain microstructure, showing randomly oriented particles and a bimodal grain size distribution. These ceramics exhibit expected mechanical properties for selenide materials with a Vickers hardness of 287 kg/mm2 and a Young's modulus of 52 GPa
A physiology-driven deep learning-based pipeline for ECG segmentation
No full textInternational audienceKnowing the durations and amplitudes of cardiac waves (P, QRS, and T) constituting the ElectroCardioGram (ECG) signal is crucial for diagnosing cardiac pathologies or predicting adverse events. Segmenting ECG waves visually by an expert can be laborious, highly time-consuming, and subjective. To cope with these limitations, an automatic segmentation of these waves emerges as the most sensible solution. However, accurate automatic segmentation of ECG waves is challenging due to the contamination of ECG signals by various types of noise and artefacts that can obscure or distort the waveforms. In this paper, a new supervised automatic ECG wave segmentation pipeline is proposed. It mainly relies on three stages. A shallow preprocessing stage that supports quasi-real-time data analysis. The second stage consists of a new multi-head attention-based CNN-LSTM model for ECG segmentation. The last stage includes a physiology-driven postprocessing algorithm aimed at addressing false positives in ECG segmentation, which significantly affects the evaluation of ECG segmentation methods. The effectiveness of the proposed three-stage pipeline compared to two standard unsupervised ECG segmentation pipelines and a recent deep learning-based approach is evaluated in this paper, using the well-known PhysioNet’s QT database. The obtained results demonstrate that the proposed pipeline outperforms the existing ones, particularly in the challenging segmentation of P and waves. The good behaviors of the proposed model also confirm the usefulness of both the use of a multi-head attention layer and the additional postprocessing algorithm
PyroBuildS: Speeding up the exploration of large configuration spaces with incremental build
No full textInternational audienceSoftware developers are acutely aware that software build is an essential but resource-intensive step in any software development process, all the more when building large and/or highly configurable systems, whose vast number of configuration options leads to an explosion in the number of variants to build and evaluate. A potential approach to speed up the builds of multiple configurations is to do incremental build, i.e., to not clean the build environment and reuse previous builds when building a new configuration. Previous exploratory studies showed some benefits and limitations of incremental build, but mainly on small configurable software systems and on a limited set of close configurations. However, for large configuration spaces, little is known whether the large distance across configurations impacts the correctness and efficiency of incremental build.This paper presents PyroBuildS, a new approach to speed up incremental builds while keeping reproducibility, featuring a configuration variation operator parameterized by two deny lists of problematic options and a mutation size (diversity).We evaluate PyroBuildS through an empirical study on three large complex configurable systems, namely Linux, BusyBox, and ToyBox, with respectively 18637, 1078, 330 configuration options. We first show that for all configurations PyroBuildS produces the exact same binaries as a clean build, except for Linux with some non-reproducible random configurations. We identify the reasons why incremental build speeds up or slows down the build of large configuration spaces – a knowledge that can be integrated into PyroBuildS. Incremental build systematically pays off, since problematic options are avoided in the first place — something only PyroBuildS does. We also show that a naive use of incremental build on random Linux configurations backfires, taking more time than clean builds. Thus, PyroBuildS controls diversity to avoid too many differences across configurations to perform efficient incremental builds.Thanks to its ability to operate over non-problematic options and close enough configurations, PyroBuildS significantly speeds up the exploration of large configuration spaces, with a gain in build time from 16% to 22% in all three systems with mutated configurations. Finally, with random configurations, PyroBuildS also speeds up the build time from 15% to 20% for ToyBox and BusyBox
