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Odyséîles : une nouvelle étape pour le suivi collaboratif du littoral de l’île d’Ouvéa (Iles Loyauté, Nouvelle-Calédonie)
No full textInternational audienc
Le poids des produits écologiques dans la satisfaction globale : une question d’asymétrie
No full textInternational audienceParmi les recherches sur l’asymétrie des facteurs qui influencent la satisfaction des consommateurs, le volet lié aux offres écologiques est encore insuffisamment étudié. C’est ce gap que comble cet article. À l’issue d’une analyse textométrique de nombreux avis envers deux marques de vêtements de sport extérieur et de trois fournisseurs d’énergie, nous développons un modèle de satisfaction pour les produits verts grâce auquel nous démontrons que les facteurs étudiés ne contribuent pas de la même manière à la satisfaction globale. En outre, ce modèle positionne l’attribut écologique comme un levier attractif qui n’entre en jeu que lorsque le consommateur exprime une satisfaction élevée. Enfin, les implications managériales de cette recherche sont discutées, notamment en termes de relation client
Probing Benchmark Models of Hidden-Sector Dark Matter with DAMIC-M
No full textInternational audienceWe report on a search for sub-GeV dark matter (DM) particles interacting with electrons using the DAMIC-M prototype detector at the Modane Underground Laboratory. The data feature a significantly lower detector single rate (factor 50) compared to our previous search, while also accumulating a ten times larger exposure of 1.3 kg-day. DM interactions in the skipper charge-coupled devices (CCDs) are searched for as patterns of two or three consecutive pixels with a total charge between 2 and 4 . We find 144 candidates of 2 and 1 candidate of 4 , where 141.5 and 0.071, respectively, are expected from background. With no evidence of a DM signal, we place stringent constraints on DM particles with masses between 1 and 1000 MeV/ interacting with electrons through an ultra-light or heavy mediator. For large ranges of DM masses below 1 GeV/c, we exclude theoretically-motivated benchmark scenarios where hidden-sector particles are produced as a major component of DM in the Universe through the freeze-in or freeze-out mechanisms
Discrete stability estimates for the pressureless Euler-Poisson-Boltzmann equations in the Quasi-Neutral limit
No full textWe propose and study a fully implicit finite volume scheme for the pressureless Euler-Poisson-Boltzmann equations on the one dimensional torus. Especially, we design a consistent and dissipative discretization of the force term which yields an unconditional energy decay. In addition, we establish a discrete analogue of the modulated energy estimate around constant states with a small velocity. Numerical experiments are carried to illustrate our theoretical results and to assess the accuracy of our scheme. A test case of the literature is also illustrated
Role of molecular alterations in transplantation decisions for patients with primary myelofibrosis
No full textInternational audienceAbstract The aim of our study was to analyze the potential survival benefit associated with hematopoietic stem cell transplantation (HSCT) according to clinicobiological scores, which incorporate mutation-enhanced international prognostic score system (MIPSS) to facilitate decision-making in this context. One transplant (n = 241) and 1 nontransplant cohort (n = 239) were used to test the hypothesis that patients with primary myelofibrosis with higher risk molecular score benefit from HSCT. A weighted propensity score was applied to balance confounding factors with the transplanted cohort as reference. Weighted Cox proportional hazard models and logistic regression analyses were performed. Overall, 105 patients who did not receive transplant could be matched to the 239 patients who did receive transplants. HSCT was associated with a higher 6-year overall survival rate in intermediate-2 (60.1% vs 41.5%) and high-risk DIPSS patients (44.4% vs 6.55%), high-risk MIPSS70 (46.5% vs 23.9%), high-risk (73.2% vs 39.7%) or very high-risk MIPSS70+V2 (51.8% vs 24%). Patients with intermediate MIPSS70 scores have an advantage of survival with HSCT only when their myelofibrosis transplant scoring system (MTSS) were low or intermediate. Patients who received transplant had an increased mortality risk the first year, but a significant benefit with HSCT after the 1-year landmark was observed in higher risk patients. This study confirms that, similar to DIPSS, MIPSS70 and MIPSS70+V2 risk score in addition to MTSS can be used to determine which patients with primary myelofibrosis have survival benefit from HSCT over non-HSCT strategies
Prognostic implications of functional tricuspid regurgitation in asymptomatic degenerative mitral regurgitation
No full textInternational audienceAims Functional tricuspid regurgitation (FTR) associated with degenerative mitral regurgitation (DMR) accentuates the severity of heart failure and is a marker of poor prognosis. Little is known about FTR associated with asymptomatic DMR. Methods and results The study included 1249 asymptomatic patients with moderate or severe DMR from the Mitral Regurgitation International Database‐Quantitative (MIDA‐Q) registry (mean age 64 ± 15 years, 25% female). Despite the asymptomatic status, absent/trivial FTR was noted in only 42%, mild in 34.5%, moderate in 11%, and severe FTR in 12.5%. Patients with higher FTR grades were older and more often female and had higher EuroScore II, larger left atrial volumes, and more atrial fibrillation (all P < 0.05). Patients with moderate or severe FTR had comparable 5‐year survival (64 ± 4% and 65 ± 4%) and lower than patients with no/trivial FTR(96 ± 1%, P < 0.001). After adjustment for key prognostic factors, including age, left ventricular dilatation and dysfunction, DMR severity, left atrial dilatation, and pulmonary hypertension, ≥moderate FTR remained a strong predictor of mortality (HR = 2.08 [1.17–3.72], P = 0.013). Sensitivity analysis showed stable impact of ≥moderate FTR among patients with/without pulmonary hypertension, in women and men and for any other subset. For patients who underwent mitral valve surgery, post‐operative survival rates were similar between those with no/trivial FTR and those with ≥moderate or severe FTR ( P = 0.76), suggesting that surgery could reduce the excess mortality related to preoperative FTR. Conclusions Among asymptomatic patients with significant DMR, ≥moderate FTR is frequent and independently associated with higher mortality, independently of traditional guideline‐based risk factors. These findings suggest that ≥moderate FTR should lead to consideration of early mitral surgery to improve outcomes
Le chantier « Agroécologie & Marché » conduit par les groupes filières INRAE
No full textLe secteur agroalimentaire fait l’objet d’une segmentation croissante du marché avec la multiplication de démarches dites de qualité, publique ou privée, qui engagent les filières dans la construction de pratiques de production, de transformation ou de distribution différenciées. Nous connaissons peu de choses sur la manière dont ces démarches inscrivent leurs pratiques dans l’agroécologie, et en particulier pour les filières ayant une mention valorisante autre que l’agriculture biologique. De 2022 à 2023, la Direction Scientifique Agriculture INRAE a engagé un chantier exploratoire, avec 11 groupes filières INRAE, pour analyser comment se construisent des démarches de filières différenciées sur le marché et leur engagement en faveur de l’agroécologie.National audienceThe agri-food sector encountered an increasing market segmentation, with the proliferation of public and private quality labels, which commit the supply chains to the building of differentiated production, processing and distribution practices. We know very little about the way in which the value chains move towards agroecology, and in particular for the value chains with quality labels other than organic farming. From 2022 to 2023, INRAE's Scientific Division for Agriculture has launched an exploratory project, with 11 INRAE value-chain groups, to analyze how differentiated supply chains are committing toward agroecology. This project, entitled “Agroecology and Market”, was based on a desk research and interviews with over 60 actors from the interbranches and different streams in agrifood chains. This introductory article presents the initial thinking behind the project, the mission of the value-chain groups and the 28 case studies selected for illustrative purposes, in order to conduct this exploratory analysis within a diversity of production and supply chain contexts.Innovations agronomiques 100 (2025), 1-12 RésuméLe secteur agroalimentaire fait l'objet d'une segmentation croissante du marché avec la multiplication de démarches dites de qualité, publique ou privée, qui engagent les filières dans la construction de pratiques de production, de transformation ou de distribution différenciées. Nous connaissons peu de choses sur la manière dont ces démarches inscrivent leurs pratiques dans l'agroécologie, et en particulier pour les filières ayant une mention valorisante autre que l'agriculture biologique. De 2022 à 2023, la Direction Scientifique Agriculture INRAE a engagé un chantier exploratoire, avec 11 groupes filières INRAE, pour analyser comment se construisent des démarches de filières différenciées sur le marché et leur engagement en faveur de l'agroécologie. Ce chantier dénommé « Agroécologie et Marché » s'est appuyé sur une analyse documentaire et une série d'entretiens auprès de plus de 60 acteurs, représentatifs d'interprofessions et de différents maillons de diverses filières. Cet article introductif présente la réflexion initiale de ce chantier, la mission des groupes filières et les 28 cas d'études retenus à titre illustratif, pour conduire cette analyse exploratoire au regard d'une diversité de contextes de production et de filières.</div
The Stochastic Light Confinement of LiquidO
No full textInternational audienceLight-based detectors have been widely used in fundamental research and industry since their inception in the 1930s. The energy particles deposit in these detectors is converted to optical signals via the Cherenkov and scintillation mechanisms that are then propagated through transparent media to photosensors placed typically on the detector's periphery, sometimes up to tens of metres away. LiquidO is a new technique pioneering the use of opaque media to stochastically confine light around each energy deposition while collecting it with an array of fibres that thread the medium. This approach preserves topological event information otherwise lost in the conventional approach, enabling real-time imaging down to the MeV scale. Our article demonstrates LiquidO's imaging principle with a ten-litre prototype, revealing successful light confinement of 90% of the detected light within a 5 cm radius sphere, using a custom opaque scintillator with a scattering length on the order of a few millimetres. These high-resolution imaging capabilities unlock opportunities in fundamental physics research and applications beyond. The absolute amount of light detected is also studied, including possible data-driven extrapolations to LiquidO-based detectors beyond prototyping limitations. Additionally, LiquidO's timing capabilities are explored through its ability to distinguish Cherenkov light from a slow scintillator
