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Differences in hospital prenatal care between immigrant and native women in France: a qualitative study within the BiP research on racial implicit bias in perinatal care
No full textInternational audienceBackground: As of 2023, 25.5% of live births in France are from mothers who were born abroad. Women born in sub-Saharan Africa are especially at risk of maternal and neonatal morbidity and mortality. Intermediate explanatory factors probably include access to and quality of care. The BiP multidisciplinary mixed-methods project sought to explore implicit racial biases among prenatal practitioners as one of the first approaches to this issue in France. The qualitative component we present here aimed to explore the clinical relationship between women from different migration backgrounds and healthcare providers as well as possible racial-based differential care in the setting of prenatal care.Methods: A sociological qualitative study was conducted in three public maternity units in the Paris area among 6 obstetrician-gynaecologists, 6 midwives, 6 anaesthesiologists, and 148 pregnant women. The study was based on audio-recorded prenatal consultations and self-confrontation interviews with practitioners. Consultations and interviews were analysed thematically.Results: The countries of birth and social positions of the participating women were globally similar to those of the pregnant women seen in each maternity unit. The content of care was globally controlled by healthcare providers and consultations were slightly longer for immigrant than native women; the explanations they provided were appropriate to women’s level of understanding. The prenatal follow-up, when standardised, left little room for differential care. Nonetheless, the tone of voice and the type of jokes showed the salience of the social relations of race and class, beyond the strict framework of the care relationship. A few instances of racism in care were identified and analysed, but their consideration by the institution was non-existent.Conclusions: French research is beginning to produce data on racial discrimination in healthcare, and this qualitative study provides an in-depth understanding of mechanisms leading to less adequate care, which was not an everyday occurrence. Despite the inclusion bias inherent in this type of approach, this study produced original results about the differential care of women who are immigrant during hospital prenatal care
Urban black-carbon radiative heating intensified by biogenic–anthropogenic interactions
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Récits et narratifs d’un changement de paradigme
No full textInternational audienceL’action en faveur d’un monde soutenable pour l’humanité est possible à conditionde prendre la mesure du défi. Dans son adresse aux décideur•se•s, l’IPBESindique par exemple « qu’il est possible de conserver, de restaurer et d’utiliser lanature de manière durable et, en même temps, d’atteindre d’autres objectifs sociétauxà l’échelle mondiale en déployant de toute urgence des efforts concertés quientraînent des changements en profondeur » (IPBES 2019, message D). Au-delà dela dimension politique de cette affirmation, appréhender de tels changements, structurels,fondamentaux, nous impose de prendre conscience de ce qui se joue dansles défis écologiques auxquels nos sociétés sont confrontées, de comprendre que lemonde va changer, radicalement et qu’on le veuille ou non, et de comprendre aussien quoi cela questionne nos valeurs, nos croyances et nos manières d’agir. Cela nousdemande d’appréhender de nouveaux récits de mondes soutenables
On the Posterior Gap in Plug & Play Diffusion Methods for Sparse-View Computed Tomography
No full textInternational audienceRecent advances in conditional diffusion models have demonstrated impressive performance on inverse problems such as Sparse-View Computed Tomography (SVCT), typically evaluated using estimation error metrics like PSNR or SSIM. However, in ultra-sparse regimes, where the number of projections is extremely limited, the sinogram is weakly informative resulting in high variability in posterior samples. This is especially true in applications involving dynamic phenomena, such as imaging the exhaust gas from a nozzle, where only a handful of projections can be captured simultaneously. In this context, evaluation based solely on estimation error (e.g. PSNR/SSIM) is no longer adequate. To address this limitation and complement the PSNR/SSIM evaluation, we propose to evaluate the Posterior Gap (PG), which measures the discrepancy between the true posterior distribution and the approximation induced by a given generative model. We introduce a practical framework for PG estimation using only prior samples, the observation model, and posterior samples. We consider three state-of-theart Plug & Play diffusion models DPS, ∏G, and FPS. Since DPS includes a sensitive hyperparameter, we present a simple calibration strategy to reduce the PG. Our study benchmarks DPS, ∏G and FPS across three SVCT datasets. Results show that when carefully calibrated, DPS outperforms FPS and ∏G. By complementing traditional metrics, our evaluation protocol offers a more comprehensive understanding of reconstruction performance, particularly in severely ill-posed regimes such as dynamic gas imaging with six or fewer projections
Benefit and risk associated with interleukin-6 receptor inhibitor administration during severe COVID-19: a retrospective multicentric study
No full textInternational audienceDuring severe and critical COVID-19, therapeutic options remain scarce. Among interventions, the use of interleukin-6 receptor inhibitor (IL-6Ri) is especially controversial due to persistent uncertainty about their efficacy and safety. To compare the occurrence of secondary infections, digestive and hematological complication function of the administration of IL-6Ri we conducted a multicentric retrospective French observational study. All severe or critical COVID-19 requiring hospital admission were included. Among 2587 patients requiring hospital admission, 1603 had a severe COVID-19 and 984 a critical one requiring ICU admission. 224 received at least one dose of tocilizumab or sarilumab. Incidence of secondary infection was 29.5% in the IL-6Ri group vs. 19.5% without IL-6Ri (p = 0.0004) in the whole population. This result remained consistent after adjustment, without multiple imputation (MI) and after MI (adjusted OR: 1.47 [1.25; 1.72]; p < 0.0001)). Incidence of hematological or digestive complication were similar between groups. Mortality of patients admitted in ward was higher in the IL-6Ri group (18.7% vs 10.5%, p = 0.0155). No difference in 28 days, ICU, hospital of 90 days mortality was noticed among ICU patients.Clinical trial registration: This study was registred on ClinicalTrial.gov: NCT05017441
On the maximal displacement of some critical branching Lévy processes with stable offspring distribution
No full textLet X be a critical branching Lévy process whose offspring distribution is in the domain of attraction of a stable random variable. We study the tail probability of the maximum location ever reached by a particle in two different situations : first when the underlying Lévy process L admits moments of order at least two and is not centered, and then when the distribution of L has a regularly varying tail. This work complements some earlier results in which either L was centered or the offspring distribution was assumed to have moments of order three
Characterization of interindividual DNA methylation variability in rainbow trout (Oncorhynchus mykiss)
No full textInternational audienceInterindividual epigenetic variability, particularly in DNA methylation, is now recognized as a significant contributor to phenotypic diversity in mammals including humans. These epivariable regions, which make up a small fraction of the genome, are strongly influenced by genetic factors and environmental factors, especially during early development. In this context, epigenetic variability of DNA methylation has been proposed as an adaptive force involved in various environmental responses. In fish and other vertebrates, environmental factors are known to influence the health, performance and welfare, likely through the alteration of the epigenetic landscape. However, whether interindividual epigenetic variability may contribute to the phenotypic plasticity of fishes is unknown. Here we provide a first description of the rainbow trout methylome interindividual variability using a whole-genome bisulfite sequencing approach in an isogenic line to minimize genetic variation. Variable methylation regions were identified in both liver and hypothalamus tissues of 12 replicate fishes and were found enriched at gene regulatory elements, such as promoters and first introns. Gene Ontology analysis revealed functional clusters related to cellular development, neural communication, metabolic balance, and immune response. Interestingly, some variably methylated regions are found at the same genomic loci in both tissues and showed a strong intraindividual correlation in methylation levels, suggesting establishment during early embryogenesis. Overall, our work demonstrates the existence of interindividual epigenetic variability in rainbow trout and provides valuable insights into the regulatory function of DNA methylation variation that is likely involved in developmental and physiological processes
Enhancer dynamics and cellular architecture in the human spinal cord
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RAC: Retrieval-Augmented Clarification for Faithful Conversational Search
No full textInternational audienceClarification questions help conversational search systems resolve ambiguous or underspecified user queries. While prior work has focused on fluency and alignment with user intent, especially through facet extraction, much less attention has been paid to grounding clarifications in the underlying corpus. Without such grounding, systems risk asking questions that cannot be answered from the available documents. We introduce RAC (Retrieval-Augmented Clarification), a framework for generating corpus-faithful clarification questions. After comparing several indexing strategies for retrieval, we fine-tune a large language model to make optimal use of research context and to encourage the generation of evidence-based question. We then apply contrastive preference optimization to favor questions supported by retrieved passages over ungrounded alternatives. Evaluated on four benchmarks, RAC demonstrate significant improvements over baselines. In addition to LLM-as-Judge assessments, we introduce novel metrics derived from NLI and data-to-text to assess how well questions are anchored in the context, and we demonstrate that our approach consistently enhances faithfulness
Measurements of Beam Spin Asymmetries of dihadrons at CLAS12
No full textInternational audienceA first measurement of beam spin asymmetries for and pairs in semi-inclusive deep inelastic scattering is reported. The asymmetries in the dihadron angular distributions were measured from the scattering of a 10.6 GeV longitudinally polarized electron beam off a proton target, using the CLAS12 detector at Jefferson Lab. A photon classifier using a Gradient Boosted Trees (GBTs) architecture was trained with Monte Carlo simulations to reduce the amount of false combinatorial background s, increasing statistics by up to five-fold compared to previous CLAS12 analyses. A nonzero asymmetry is observed. This measurement is sensitive to the underexplored collinear twist-3 PDF , which encodes quark-gluon correlations in the proton, and presents a new avenue for its point-by-point extraction. The asymmetries also provide the first experimental evidence for the isospin-dependence of the helicity-dependent dihadron fragmentation function , revealed by a sign-difference between the and channels in the modulation. In contrast, a large, same-sign enhancement near the mass for the modulation is observed, matching spectator model predictions in pairs