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Weakly modeled search for compact binary coalescences in the Einstein Telescope
No full textInternational audienceWe search for gravitational-wave (GW) signals from compact binary coalescences (CBC) in the mock data challenge of the Einstein Telescope (ET) with a detection algorithm that does not rely on the waveform of the signal searched. With the increased sensitivity of ET compared to current GW detectors, a very high rate of detectable sources is expected in the data, and the computational cost of the searches may become a limiting factor. This is why we explore the behavior of a weakly modeled search algorithm, which is intrinsically less sensitive than optimal search methods based on matched filtering techniques, but computationally much cheaper. This search recovers a significant fraction of CBC signals present in the data: 38% of the total number of binary black hole mergers, including 89% of the systems with a total mass above 100 solar masses, as well as the majority of binary neutron star (BNS) mergers closer than 850 Mpc (z=0.17). It is also able to estimate the chirp mass of the recovered BNS with an average precision of 1.3%. We also find that the usual method for estimating the background in transient GW searches, that consists in time-shifting the data from one detector with respect to the others, is impacted by the presence of loud CBC signals in the data, so we use the null stream instead as a signal-free channel to estimate the background of this search
Evaluation de l'implémentation d'interventions en milieu scolaire visant à améliorer la couverture vaccinale HPV en France : résultats d'une étude mixte au sein de l'essai contrôlé randomisé PrevHPV
No full textInternational audienceBackground and objective(s)Human papillomavirus (HPV) vaccine coverage (VC) remains lower than expected in many countries, particularly France. In 2018, the French authorities launched the PrevHPV research program to codevelop school- and primary care-based interventions with stakeholders and evaluate their effectiveness and implementation. The school-based interventions were ‘education and motivation’ and ‘at-school vaccination’. Analyses, without considering the dose of intervention received, showed that only the ‘at-school vaccination’ intervention significantly increased VC at two months. Implementation weaknesses may negatively impact effectiveness; therefore, it is worth having an in-depth understanding of the intervention implementation. This investigation aimed to evaluate the implementation of the school-based interventions of the PrevHPV program.Material and MethodsWe carried out a mixed-method study embedded in the national cluster randomized controlled trial PrevHPV (July 2021-June 2022). The cluster was the municipality (n=91). The ‘education and motivation’ intervention consisted (i) for parents, of a web conference on HPV infection and vaccination; and, (ii) for 8th–9th grade pupils, of two educational group sessions on those topics during school hours, using participatory learning and e-health tools. The ‘at-school vaccination’ intervention consisted of offering free vaccination to all pupils whose parents agreed on school premises. Quantitative data were collected through standardized activity reports and self-administered questionnaires; the implementation outcomes were fidelity, dose, reach, acceptability and sustainability. Qualitative data were collected through semi-structured group interviews with school staff and analyzed using the Consolidated Framework for Implementation Research.ResultsWe found high rates for: fidelity (e.g., 69% of the targeted classes had two sessions and 89% of schools invited all pupils for at-school vaccination); acceptability (e.g., pupils’ attentiveness and participation satisfying in 90% of the sessions, 96% of vaccinated pupils and 78% of school staff satisfied with the organization of vaccination days); and sustainability (e.g., 91% and 76% of participating schools considered conducting sessions and vaccination days the following year, respectively). However, the withdrawal of 1/3 of schools before the trial started and difficulties in mobilizing parents (e.g., <1% of invited parents participated in a web conference) negatively impacted dose and reach. Facilitators of and barriers to the implementation related to the intervention content and format, the characteristics of both the external and internal environment of the school, the numerous stakeholders and individuals involved, and the implementation strategies used. Facilitators included well-designed provided tools, supportive regulations, motivated leaders, and the presence of an external facilitator; barriers included staff workload, financial and material resources.ConclusionSchools can play a significant role in HPV vaccine promotion but are challenging settings for implementation. This study highlights challenges for involving stakeholders (parents, school staff) and the organizational changes this implies. This study has practical implications for implementing such interventions in real life, which is more valuable since HPV vaccination has been offered at school to all French 7th-grade pupils since 2023
The Canis lupus ssp. (Mammalia, Carnivora) of the Baume Traucade (Issirac, Gard, France): A complete skeleton of a “dog-like” individual from the post-LGM
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Erosion, soulèvement tectonique, et terrasses: modélisation de l'évolution morphologique des côtes des Andes Centrales
No full textInternational audienceWe devise a numerical model based on simple considerations to simulate marine erosion and coastal morphogenesis. Marine erosion results in the landward retreat of the shore and in the appearance of an offshore platform. Since more energy is needed to erode an uplifting platform, the faster the tectonic uplift, the shorter the coastal platform. For that reason, the present-day cross-shore topographic profiles fingerprint the long-term (Pliocene/Pleistocene) variations of the tectonic uplift velocities. Increasing the uplift rate leads to the emersion of a part of the offshore platform that converts into a marine terrace. In contrast, the offshore platform widens when the uplift rate decreases. It results in the landward retreat of the coastline and eventually undermines antecedent terraces; Thus, missing terraces may simply result from a diminution of the coastal uplift velocity. We illustrate these results considering some coastal sectors along the Pacific shore of the Central Andes, where aridity preserves the emerged coastal landforms from subaerial erosion, and where many model simplifications are conveniently justified. The model suggests that the tectonic motions during the growth of the Great Coastal Escarpment, that conforms most of the Central Andes between 15°S and 27°S, must have remained slow enough to allow for the formation of such a gigantic morphological feature. The analysis of the coastal morphology of Northern Chile also shows that although the coastal area generally uplifted during the Pleistocene, the rate of uplift varied significantly and the pulses of uplift were not everywhere synchronous.Presentamos un modelo numérico basado en consideraciones simples para simular la erosión marina y la morfogénesis costera. La erosión marina provoca el retroceso de la línea de costa hacia el interior del continente y el desarrollo de una plataforma marina. Ya que se necesita más energía para erosionar una plataforma ascendente, cuanto más rápido sea el levantamiento tectónico, más estrecha será la plataforma. Por eso, los perfiles topográficos perpendiculares a la costa indican las variaciones tectónicas a largo plazo (Plioceno/Pleistoceno). Un aumento de la velocidad de alzamiento resulta en la emersión de una parte de la plataforma y en la aparición de una terraza marina. En cambio, la plataforma se ensancha si disminuye la velocidad de alzamiento, la línea de costa retrocede hacia el interior, eliminando finalmente las terrazas más antiguas. Ilustramos estos resultados observando unos sectores de la costa del Pacífico de los Andes centrales, donde la aridez del desierto de Atacama preserva el relieve de la erosión subaérea, y donde las numerosas simplificaciones adoptadas para este modelo estan justificadas. El modelo sugiere que los movimientos tectónicos durante el crecimiento del Gran Escarpe Costero entre 15°S y 27°S deben haber permanecido lo suficientemente lentos como para permitir la formación de un objeto geomorfológico tan espectacular. El análisis de la morfología costera del norte de Chile también muestra que, aunque la zona costera se elevó en general durante el Pleistoceno, la tasa de elevación varió significativamente y los episodios de elevación no fueron sincrónicos en todas partes.Nous présentons un modèle numérique basé sur des considérations simples pour simuler l'érosion marine et la morphogenèse côtière. L'érosion marine entraîne le recul du rivage vers l'intérieur des terres et l'apparition d'une plate-forme offshore. Comme il faut plus d'énergie pour éroder une plate-forme qui se soulève, plus le soulèvement tectonique est rapide, plus la plate-forme est étroite. Pour cette raison, les profils topographiques actuels perpendiculaires à la côte reflètent les variations long terme (pliocène/pléistocène) des vitesses de soulèvement tectonique. L'augmentation de la vitesse de soulèvement entraîne l'émersion d'une partie de la plate-forme qui se transforme en terrasse marine. En revanche, la plate-forme s'élargit lorsque la vitesse de soulèvement diminue. Il en résulte un recul de la ligne de côte vers l'intérieur des terres, qui finit par éliminer les terrasses plus anciennes. Nous illustrons ces résultats en observant certains secteurs de la côte Pacifique des Andes centrales, où l'aridité du Désert d'Atacama préserve le relief de l'érosion subaérienne, et où les nombreuses simplifications adoptées pour ce modèle peuvent être justifiées. Le modèle suggère que les mouvements tectoniques pendant la croissance du grand escarpement côtier, présent entre 15°S et 27°S, ont dû rester suffisamment lents pour permettre la formation d'un objet géomorphologique aussi spectaculaire. L'analyse de la morphologie côtière du nord du Chili montre également que, bien que la zone côtière se soit généralement soulevée au cours du Pléistocène, le taux de soulèvement a varié de manière significative, et que les épisodes de soulèvement n'ont pas été partout synchrones
Structural signatures of language reorganization after left hemispherotomy in patients with Rasmussen’s encephalitis
No full textInternational audienceRasmussen’s encephalitis (RE) is a rare neurological disorder affecting a single cerebral hemisphere, often requiring hemispherotomy as a curative treatment. While significant brain plasticity occurs due to the pathology and surgical intervention, the mechanisms underlying cognitive functioning in the remaining hemisphere remain poorly understood. This multiple-case study longitudinally investigates neurocognitive reorganization in childhood after left hemispherotomy for RE and identifies structural patterns in the right hemisphere associated with language recovery. Indeed, the mechanisms that allow the right hemisphere to support language, after left hemispherotomy remain unclear. Cognitive trajectories were analyzed in three RE patients, and their cortical thickness (CT) changes were compared with data from a publicly available cohort of 393 healthy subjects. Language neuropsychological scores and T1-weighted MRI data were assessed in the healthy right hemisphere before hemispherotomy, one year, and five years post-surgery. Specifically, principal component analysis, structural covariance, and graph theory approaches were employed to investigate language network organization in patients and controls. Results reveal diverse language recovery trajectories among the three patients. Regarding CT, three potential signatures associated with favorable language outcomes were identified: (1) normal or below-normal CT values in cortical regions; (2) a more associative and integrative organization of the language network; and (3) increased global efficiency. These preliminary longitudinal findings provide novel insights into the mechanisms of neurocognitive reorganization following left hemispherotomy in childhood. By emphasizing structural patterns linked to favorable postoperative language recovery, this study highlights their value for guiding future research and clinical interventions
Observation of the decay and measurement of the branching fractions
No full textInternational audienceA study of the charmless baryonic decays is presented, where denotes either a or a meson. The analysis is based on proton-proton collision data collected by the LHCb experiment at centre-of-mass energies of 7, 8, and , corresponding to an integrated luminosity of . The decay is observed for the first time, with a measured branching fraction of and a significance of . The uncertainties respectively account for statistical and systematic contributions, the precision of the branching fraction of the normalisation channel and the fragmentation fraction ratio . The branching fraction determined for is , which is the most precise measurement to date
Measurements of inclusive and differential cross sections for top quark production in association with a Z boson in proton-proton collisions at = 13 TeV
No full textInternational audienceMeasurements are presented of inclusive and differential cross sections for Z boson associated production of top quark pairs (Z) and single top quarks (tZq or tWZ). The data were recorded in proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 138 fb. Events with three or more leptons, electrons or muons, are selected and a multiclass deep neural network is used to separate three event categories, the Z and tWZ processes, the tZq process, and the backgrounds. A profile likelihood approach is used to unfold the differential cross sections, to account for systematic uncertainties, and to determine the correlations between the two signal categories in one global fit. The inclusive cross sections for a dilepton invariant mass between 70 and 110 GeV are measured to be 1.14 0.07 pb for the sum of Z and tWZ, and 0.81 0.10 pb for tZq, in good agreement with theoretical predictions
Semileptonic decays from light to leptons: the extraction of the form factor from data
No full textInternational audienceWe extend the Standard Model (SM) analysis of Ref. [1], which was limited to light leptons in the final state, to the semileptonic decay. By using quantities that can be analised without the knowledge of , we derive important information about the helicity amplitudes and the hadronic form factors that can be compared with the predictions of lattice QCD calculations. In particular, there is a difficulty in reproducing simultaneously the experimental values of and of other quantities relevant for the semitauonic decays within the SM. As a byproduct of our analysis, we also present a determination of from the total decay rate
Validating the rhenium proxy for rock organic carbon oxidation using weathering profiles
No full textInternational audienceChemical weathering over geological timescales acts as a source or sink of atmospheric carbon dioxide (CO2), while influencing long-term redox cycling and atmospheric oxygen (O2) at Earth's surface. There is a growing recognition that the oxidative weathering of rock organic carbon (OCpetro) can release more CO2 than is locally drawn down by silicate weathering, and may vary due to changes in erosion and climate. The element rhenium (Re) has emerged as a proxy to track the oxidative weathering of OCpetro, yet uncertainties in its application remain namely that we lack a systematic assessment of the comparative mobility of Re and OCpetro during sedimentary rock weathering. Here we measure Re and OCpetro loss across gradients in rock weathering at 12 global sites, spanning a range of initial OCpetro values from ~0.2 % to >10 %. At nine sites we use titanium to account for volume changes during weathering and assess Re and OCpetro loss alongside major elements that reflect silicate (Na, Mg), carbonate (Ca, Mg) and sulfide (S) weathering. Across the dataset, Re loss is correlated with OCpetro loss but not with loss of any other major element. Across the weathering profiles, the average molar ratio of OCpetro to Re loss was 0.84 ± 0.15, with 8 out of 9 sites having a ratio >0.74. At one site (Marcellus Shale), the average ratio was lower at 0.58 ± 0.11. The excess loss of Re matches expectations that, typically, between ~0 and 20 % of the Re liberated by sedimentary rock weathering derives from silicate or sulfide phases, while some OCpetro may be physically or chemically protected from weathering. Overall, our measurements provide validation for the Re proxy of OCpetro oxidation and allow future work to further improve our knowledge of regional and global-scale rates of this important source of CO2 in the geochemical carbon cycle
Ten to 15-Year Outcomes of Monoblock Uncemented Dual Mobility Cups
No full textInternational audienceBackground: Dual mobility cups (DMCs) have effectively prevented dislocations after total hip arthroplasty (THA). However, use of these cups in primary THAs remains controversial, especially in young patients. This study aimed to determine the long-term survival rate and functional outcomes of a contemporary DMC used in primary THA. Methods: This retrospective multicenter study identified a cohort of 614 primary THAs performed with the same uncemented monoblock DMC between 2007 and 2010. Survival analysis included 572 THAs, while clinical analysis involved 394 THAs at a minimal follow-up of 10 years. The mean follow-up was 11.1 ± 1.2 years. The mean age was 71.4 ± 11.7 years, with 4.2% of patients under 50 years old. The mean body mass index was 27.0 ± 5.3 kg/m 2 . The 10-year Kaplan-Meier survival rate was calculated based on cup removal for any reason or cup revision for an aseptic reason as the end point. Harris hip scores were collected at the last follow-up. Results: The cup-revision-free survival rate was 98.6% at 10 years and 96.2% at 13 years. No cup revisions were reported due to aseptic loosening or dislocation. The cup revisions were due to infection (7 of 572; 1.2%), acetabular fracture (1 of 572; 0.17%), and psoas impingement due to cup malpositioning (n = 1 of 572; 0.17%). Only 3 dislocations (0.52%) were observed, and they did not require revision. The mean Harris hip score significantly improved from 54.1 ± 14.4 preoperatively to 88.0 ± 14.3 at the last follow-up (p < 0.0001). For patients under 50 years old at the time of surgery, the mean Harris hip score showed significant improvement from 53.0 ± 10.2 preoperatively to 89.7 ± 12.8 at the last follow-up (p < 0.0001), with no significant difference compared with the older patients (p = 0.50). No revision or complication was reported in the younger patient population at 13 years of follow-up. Conclusions: The monoblock uncemented DMC demonstrated excellent survival rates with no DMC-specific complications during a minimum 10-year follow-up. The dislocation rate was very low, and a younger age was not identified as a risk factor for failure. Therefore, monoblock cementless DMCs can be safely used, even in primary THA. Level of Evidence: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence