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Fathers have embraced longer and more flexible paternity leave
No full textInternational audienceReformed in 2021, paternity leave in France was extended and made more flexible. The proportion of fathers taking this leave continues to grow, particularly among those that used to claim it least, such as self-employed workers, those on fixed-term contracts, and the least-educated fathers. Fathers’ presence at the birth of their child and beyond is becoming the norm. However, occupational and financial pressures remain an obstacle to the use of paternity leave. Only a minority of fathers take a “solo” paternity leave after the mother’s return to work, but these numbers are increasing.La réforme du congé de paternité en 2021 a allongé sa durée et assoupli ses modalités. La part de pères prenant ce congé continue à augmenter, notamment chez ceux qui y avaient le moins recours comme les indépendants, les salariés en contrat à durée déterminée, les pères moins diplômés. La présence des pères au moment de la naissance se généralise et dure plus longtemps. Cependant, les contraintes professionnelles et financières restent un frein à la prise du congé. Même s’ils restent minoritaires, les pères qui prennent le congé « en solo », alors que la mère a repris le travail, sont de plus en plus nombreux
La biochimie des interactions conservées de la levure à l'homme pour la voie NMD
No full textNonsense-mediated mRNA decay (NMD) is one of the most extensively studied pathways of cytoplasmic mRNA degradation. It plays a critical role in diverse cellular processes by eliminating aberrant transcripts containing premature stop codons and by regulating the stability of physiological mRNAs. NMD factors were initially identified through genetic screens in S. cerevisiae (UPF1, 2, 3) and C. elegans (SMG-1, SMG5-7). Subsequent biochemical studies revealed the composition of NMD complexes and identified additional factors. A major protein hub for NMD is Upf1, an ATP-dependent RNA helicase that is part of two mutually exclusive NMD assemblies, the Upf1-Upf2-Upf3 complex and the Upf1-decapping complex, which contains the decapping enzyme and its co-factors. Here, we discuss recent findings, primarily from budding yeast, on the protein-protein interactions driving NMD complex dynamics and their similarities to human NMD. Together, the N-terminal cysteine and histidine rich (CH) and helicase domains (HD) of Upf1 act as a hub for binding multiple partners. Upf1 is required for binding to NMD substrates and for the initiation of RNA degradation through decapping (yeast) or endonucleolytic hydrolysis (humans). We focus on the interplay between Upf2, Dcp2 and Nmd4 (yeast SMG6), which ensures the mutually exclusive formation of Upf1-bound subcomplexes modulating Upf1's affinity for RNA. Thus, the study of NMD factors interactions in different organisms sheds new light on the remarkable conservation of NMD molecular mechanisms
Search for dark matter produced in association with a Higgs boson decaying to bottom quarks in proton-proton collisions at = 13 TeV
No full textInternational audienceA search for dark matter particles produced in association with a Higgs boson decaying to a bottom quark-antiquark pair in proton-proton collisions at = 13 TeV is presented. The data, collected with the CMS detector at the LHC, correspond to an integrated luminosity of 101 fb. The analysis is performed in exclusive categories targeting both Lorentz-boosted (merged) and resolved b jet pair topologies, covering a wide range of Higgs boson transverse momentum. A statistical combination is made with a previous search using data collected in 2016 and corresponding to an integrated luminosity of 35.9 fb. The observed data agree with the standard model background predictions. Constraints are placed on models predicting new particles or interactions, such as those in the simplified frameworks of baryonic-Z' and 2HDM+a, where the latter is a type-II two-Higgs-doublet model featuring a heavy pseudoscalar with an additional light pseudoscalar. Upper limits at 95% confidence level are set on the production cross section for these models. For the baryonic-Z' model, Z' boson masses below 2.25 TeV are excluded for a dark matter particle candidate mass of 1 GeV. In the 2HDM+a model, heavy pseudoscalar masses between 850 and 1300 GeV are excluded for a light pseudoscalar mass of 350 GeV
Offline Contextual Bandit with Counterfactual Sample Identification
No full textRecsys '25, CONSEQUENCES: Causality, Counterfactuals & Sequential Decision-Making WorkshopIn production systems, contextual bandit approaches often rely on direct reward models that take both action and context as input. However, these models can suffer from confounding, making it difficult to isolate the effect of the action from that of the context. We present Counterfactual Sample Identification, a new approach that re-frames the problem: rather than predicting reward, it learns to recognize which action led to a successful (binary) outcome by com-paring it to a counterfactual action sampled from the logging policy under the same context. The method is theoretically grounded and consistently outperforms direct models in both synthetic experi- ments and real-world deployments
Extracting light-cone wave functions from covariant amplitudes: a detailed study in scalar field theory
No full textInternational audienceWe propose a conjectured formula that systematically maps covariant off-shell amplitudes to light-cone wave functions in scalar field theory. Through an explicit comparison at one-loop accuracy, we establish its equivalence to the light-cone perturbation theory series, thereby validating the conjecture at this order. Applying this formula, we efficiently re-derive wave functions from known covariant amplitudes, bypassing both the conceptual complexities of light-cone quantization and the technical challenges of perturbative calculations in this framework. In addition to simplifying computations, this approach opens new avenues for applications in gauge theories and deeper explorations of the fundamental equivalence between covariant and light-cone quantization
Global transport of stratospheric aerosol produced by Ruang eruption from EarthCARE ATLID, limb-viewing satellites and ground-based lidar observations
No full textInternational audienceThe Atmospheric LIDar (ATLID) instrument of the ESA’s Earth Cloud, Aerosol and Radiation Explorer (EarthCARE) satellite mission launched in May 2024 provides high-resolution vertical profiling of aerosols and clouds at 355 nm. Fully operational since July 2024, ATLID has been witness to a significant perturbation of stratospheric aerosol budget following the eruptions of Ruang volcano (Indonesia) in late April 2024. Using ATLID together with limb-viewing satellite instruments (OMPS-LP and SAGE III), we quantify the stratospheric aerosol perturbation generated by the Ruang eruption and characterize the global transport of volcanic aerosols. To evaluate the ATLID performance in the stratosphere, its data are compared with collocated ground-based lidar observations at various locations in both hemispheres and overpass-coordinated balloon flights carrying AZOR backscatter sonde. The intercomparison with suborbital observations suggests excellent performance of ATLID in the stratosphere and proves its capacity to accurately resolve fine structures in the vertical distribution of stratospheric aerosols. Using various satellite observations, we show that Ruang’s eruptive sequence in April 2024 produced eruptive columns reaching 25 km altitude, and resulted in a doubling of the tropical stratospheric aerosol abundance for several months. The eruption timing in austral Fall and its high-altitude reach fostered efficient poleward transport into the southern extratropics during austral Winter 2024. By the time of the austral Fall 2025, the sulphate aerosols from Ruang have spread across the entire Southern hemisphere and were most probably entrained by the 2025 Antarctic polar vortex, potentially enhancing the polar stratospheric cloud occurrence
A comprehensive analysis of the decay
No full textInternational audienceAn analysis of the decay is presented using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 8.4 fb. The full set of -averaged and -asymmetric angular observables is determined in bins of the invariant mass squared of the dimuon system, as well as the branching fraction relative to the decay. For the first time, the full set of observables pertaining to the S-wave contribution to the final state are presented and consideration is given to effects arising from the mass of the muons. The measurements of the -averaged observables and the branching fractions continue to exhibit the pattern of tensions with the Standard Model predictions that have been seen in previous analyses that use part of the dataset considered in this study. The extracted -asymmetry observables show no significant deviations from zero
Modeling high dimensional point clouds with the spherical cluster model
No full textA parametric cluster model is a statistical model providing geometric insights onto the points defining a cluster. The spherical cluster model (SC) approximates a finite point set P ⊂ R d by a sphere S(c, r) as follows. Taking r as a fraction η ∈ (0, 1) (hyper-parameter) of the std deviation of distances between the center c and the data points, the cost of the SC model is the sum over all data points lying outside the sphere S of their power distance with respect to S. The center c of the SC model is the point minimizing this cost. Note that η = 0 yields the celebrated center of mass used in KMeans clustering. We make three contributions.First, we show fitting a spherical cluster yields a strictly convex but not smooth combinatorial optimization problem. Second, we present an exact solver using the Clarke gradient on a suitable stratified cell complex defined from an arrangement of hyper-spheres. Finally, we present experiments on a variety of datasets ranging in dimension from d = 9 to d = 10, 000, with two main observations. First, the exact algorithm is orders of magnitude faster than BFGS based heuristics for datasets of small/intermediate dimension and small values of η, and for high dimensional datasets (say d > 100) whatever the value of η. Second, the center of the SC model behave as a parameterized high-dimensional median.The SC model is of direct interest for high dimensional multivariate data analysis, and the application to the design of mixtures of SC will be reported in a companion paper
Machine-Learning Text Analysis of Intergenerational Mobility Perceptions in Germany, Sweden, and the United Kingdom
No full textResearch on intergenerational mobility has traditionally focused on objective markers of socioeconomic position. In this study, we argue that the subjective aspects of intergenerational mobility deserve greater attention and empirically explore what individuals report they compare when they gauge their intergenerational mobility trajectories. Drawing on representative survey data from Germany, Sweden, and the United Kingdom, as well as machine-learning-driven text analyses of open-ended survey responses, we reveal that, in addition to conventional measures of intergenerational mobility, such as education, occupational status, and income, individuals consider a diverse array of factors, including family life, home ownership, and lifestyle choices. Our findings highlight the heterogeneity of these comparisons across different countries, genders, and generations. We identify significant variations in the dimensions of intergenerational comparisons, such as the prominence of education in Sweden, the focus on housing in the United Kingdom, and the salience of freedom, opportunity, and lifestyle in Germany. Furthermore, gender differences reveal that females are more likely to emphasize education and family life, while males focus on income and occupational status. These insights provide a deeper understanding of the subjective dimensions of intergenerational mobility and contribute to ongoing debates in social stratification research and general social theory
Measurement and effective field theory interpretation of the photon-fusion production cross section of a pair of W bosons in proton-proton collisions at = 13 TeV
No full textInternational audienceThis analysis presents an observation of the photon-fusion production of W boson pairs using the CMS detector at the LHC. The total cross section of the WW production in photon fusion is measured using proton-proton collision data with an integrated luminosity of 138 fb collected with the CMS detector in 20162018 at a center-of-mass energy of = 13 TeV. Events are selected in the final state with one isolated electron and one isolated muon, and no additional tracks associated with the electron-muon production vertex. The total and fiducial production cross sections are 643 fb and 3.96 fb, respectively, in agreement with the standard model predictions of 631 126 fb and 3.87 0.77 fb. This agreement enables stringent constraints to be imposed on anomalous quartic gauge couplings within a dimension-8 effective field theory framework