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Extraction of Contrastive Rules from Syntactic Treebanks: A Case Study in Romance Languages
No full textInternational audienceIn this paper, we develop a data-driven contrastive framework to extract common and distinctive linguistic descriptions from syntactic treebanks. The extracted contrastive rules are defined by a statistically significant difference in frequency and precision, and classified as common and distinctive rules across the set of treebanks. We illustrate our method by working on object word order using Universal Dependencies (UD) treebanks in 6 Romance languages: Brazilian Portuguese, Catalan, French, Italian, Romanian and Spanish. We discuss the limitations faced due to inconsistent annotation and the feasibility of conducting contrastive studies using the UD collection
Premiers crabes sur nos continents
No full textInternational audienceIl existe plusieurs degrés de terrestrialité chez les crabes incluant de vivre sur l'estran, dans les estuaires, dans les rivières et même dans les forêts. Ces degrés impliquent des adaptations biologiques liées à la respiration, la thermorégulation, la faculté de muer, ou encore la reproduction. Ces adaptations se reflètent dans l'anatomie des crabes : épaississements localisés de leur cuticule, soies et organes de respiration spécialisés, dont la plupart ne se fossilisent que rarement. Les crabes continentaux modernes sont répartis dans une dizaine de familles. Les relations de parenté de ces familles suggèrent que la transition d'une vie marine à continentale a eu lieu plusieurs fois (entre 12 et 17 fois !) avec les premières transitions au début du Crétacé inférieur. Pendant longtemps, les plus anciens fossiles de crabes continentaux remontaient à l'Éocène et laissaient penser à l'existence d'au moins deux transitions. Des pinces isolées plus anciennes étaient connues dans des dépôts continentaux, notamment associées à des ossements de dinosaures, mais leur identification était incertaine. La découverte récente d'un crabe exceptionnellement bien conservé dans de l'ambre du Crétacé du Myanmar, illustre une lignée étonnamment moderne. La structure des branchies de ce crabe indique qu'il était aquatique à amphibie (pas de place pour un « poumon ») et qu'il vivait en eau douce. La découverte illustre une étape précoce de la colonisation précoce du milieu continental par les crabes, il y a 100 millions d'années
Wideband photomixing antenna array in the W-band based on multilayer PCB technology
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Virtual focus synthesis for low-profile reconfigurable transmitarrays
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Antiferromagnetism, Anion Disorder, and Lattice Defects in the S = 5/2 [Bi2O2][Mn2+F4] Aurivillius Compound
No full textInternational audience[Bi2O2][MnF4] is an Aurivillius oxyfluoride phase with Mn2+ cations filling the one-layer perovskite subunits. Its synthesis as a single-phase material by a high-temperature solid-state route is complicated by the high volatility of fluorine in the used precursors and by its limited thermal stability above 400 °C. Its crystal structure was determined using synchrotron and neutron diffraction data. It shows structural singularities, highlighted by the anion positional disorder inherent to the I4/mmm space group, despite the evidence of strong local axial and equatorial octahedral tilts along with clues for ideal F– and O2– total segregation in the two-layered subunits. Contrarily to the M = Ni2+, Co2+, and Fe2+/3+ analogs, where similar tilts order in various supercells, for M = Mn2+ only short-range ordering (SRO) was detected by electron diffraction. This was rationalized in terms of the d5 ion isotropic nature for which weak distortions of the crystal field do not have an energy penalty and favor local octahedral defects acting as antiphase boundaries between nanometric SRO domains. DFT calculations validate equiprobable tilted [MnF6] arrangements in the perovskite layers and suggest the possibility for an O ↔ F exchange between the [Bi2O2] and [MnF4] modules, supported by HAADF imaging. The presence of oxygen and vacancies in the perovskite slabs was also detected in samples prepared at higher temperatures. [Bi2O2][MnF4] magnetic structure shows a colinear antiferromagnetic arrangement below TN = 19.8 K, with Mn2+ spins (S = 5/2, L = 0) aligned parallel to the c-axis (Mz = 3.8(2) μB/Mn). This is again in contrast with the systematic spin-canting responsible for weak ferromagnetism in the previous M2+ Aurivillius compounds. Finally, the modest fluoride ionic mobility was measured in a small temperature range, restricted by the stability of the compound in air
Allocation and prognosis of temporary mechanical circulatory support in unselected cardiogenic shock: Insights from the FRENSHOCK registry
No full textInternational audienceBackground: Patients in cardiogenic shock (CS) can benefit from temporary mechanical circulatory support (tMCS) but data in heterogeneous populations with diverse CS aetiologies are rare.Aims: To compare baseline characteristics, management and independent correlates of 30-day and 1-year mortalities between patients managed with and without tMCS for CS.Methods: The FRENSHOCK registry (NCT02703038) included 772 unselected patients with CS admitted in 49 French critical care units between April and October 2016.Results: Among 770 patients with CS and available data, 135 (17.5%) received tMCS (63 extracorporeal life support, 35 intra-aortic balloon pump, 13 micro-axial flow pump and 24 combination), of whom 69.0% were implanted during the first 24hours. Patients with tMCS were less likely to present with histories of cardiac or peripheral artery diseases or chronic renal failure. An ischaemic or mechanical complication trigger for CS tripled the probability of receiving tMCS, while increased lactate doubled the probability. Thirty-day mortality was higher among patients with versus without tMCS (34.1% vs. 24.3%; P<0.001), but after adjustment for age and CS severity (LVEF and arterial lactates at admission, noradrenaline and invasive mechanical ventilation use), the difference was no longer significant (hazard ratio: 1.37, 95% confidence interval: 0.93-2.01). Among 30-day survivors, mortality was similar regardless of initial receipt of tMCS (P=0.312).Conclusion: In real-life practice, tMCS may not be associated with improvements in 30-day or 1-year mortality in an all-comers cohort of patients with CS. However, it should be noted that there were substantial differences in patient characteristics and management between patients who received tMCS and those who did not. Additional targeted studies should help to determine more precise algorithms for granting assistance within the complex and heterogeneous population of patients with CS
Les actions du CSF électronique pour l’emploi et le développement des compétences
No full textNational audiencePrésentation orale avec actes, doublée d'un support poste
Improving Multimodal Distillation for 3D Semantic Segmentation under Domain Shift
No full textInternational audienceSemantic segmentation networks trained under full supervision for one type of lidar fail to generalize to unseen lidars without intervention. To reduce the performance gap under domain shifts, a recent trend is to leverage vision foundation models (VFMs) providing robust features across domains. In this work, we conduct an exhaustive study to identify recipes for exploiting VFMs in unsupervised domain adaptation for semantic segmentation of lidar point clouds. Building upon unsupervised image-to-lidar knowledge distillation, our study reveals that: (1) the architecture of the lidar backbone is key to maximize the generalization performance on a target domain; (2) it is possible to pretrain a single backbone once and for all, and use it to address many domain shifts; (3) best results are obtained by keeping the pretrained backbone frozen and training an MLP head for semantic segmentation. The resulting pipeline achieves state-of-the-art results in four widely-recognized and challenging settings. The code will be available at: github.com/valeoai/muddos
The inflammatory effects of a repeated exposure of human macrophages to PM2.5 from house dust-SRM 2585 are partially reversible and disrupt the LPS/CD14 signaling pathways
No full textInternational audienceObjectives: To evaluate whether repeated exposures to house dust PM2.5, used at nontoxic concentrations, activate human macrophages after one- and seven-days post-treatment, and whether such PM2.5 exposure may alter their response to LPS.Methods: Human monocyte-derived macrophages (MDMs) were repeatedly (4 consecutive days) exposed to 1 and 10 μg/cm2 house dust PM2.5 fraction of SRM 2585®. MDM phenotype and functions were evaluated by flow cytometry and ELISA one- and seven-days after the last PM2.5 exposure with or without LPS priming during the last 24 h of exposure.Results: PM2.5 used at non cytotoxic concentrations induced a pro-inflammatory phenotype characterized by an increased expression of M1 macrophagic markers (CD40, CD80, CD86) and pro-inflammatory cytokines (IL-6, IL-8, TNFα) and a decreased expression of M2 macrophagic markers (CD163, CD204) and of the anti-inflammatory cytokine IL-10, however depending of post-exposure time and the concentration. PM2.5-induced polarization profile of MDM was reversible when they were exposed to 1 μg/cm2 but not to 10 μg/cm2. PM2.5-primed MDMs and then exposed to LPS showed a pro-inflammatory phenotype characterized by altered secretion of IL-8 and IL-10, a decreased expression of CD14, scavenger receptors (SR)-A1 and interferon responsive genes (CXCL9/10, ISG15) and a decrease of endocytosis and phagocytosis of bacteria.Conclusions: Repeated exposures, even to low concentration of house dust PM2.5, primed MDMs to a pro-inflammatory phenotype that is only partly reversible seven days post-exposure. The altered response of PM2.5-pre-exposed MDMs to LPS might be due to, at least in part, impaired endocytosis crucial for the TLR4/CD14 pathway
