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Observation of orbitally excited states
No full textInternational audienceThe observation of a wide peaking structure in the mass spectrum is reported using proton-proton collision data collected by the LHCb detector at center-of-mass energies of , and , corresponding to a total integrated luminosity of . The statistical significance over the background-only hypothesis exceeds seven standard deviations. The width of the observed structure is larger than the expectation from a single-peak hypothesis, and is well described by an effective minimal model consisting of two narrow peaks located at and . The uncertainty terms are statistical, systematic, and associated to the knowledge of the mass, respectively. The measured peak locations are in line with theoretical predictions for lowest excited -wave states, marking the first observation of orbitally excited beauty-charm mesons and providing important insights into the internal dynamics of hadrons containing two heavy quarks
Correlation of synthesis parameters and physicochemical properties of biomass-derived carbon-titania composites
No full textInternational audienceThe synthesis of an efficient lithium battery anode requires active and conductive materials. Composites are often used, but their preparation requires numerous parameters and attempts to maximize the crystalline phase or texture. To limit the number of syntheses, factor analysis is a useful tool for determining the critical parameters. This method has been applied to titania-based anodes. Biomass-derived carbon-titania composites were prepared through sol–gel synthesis followed by drying and pyrolysis under a nitrogen gas flow. Four synthesis parameters were investigated: the presence of kapok-based carbon fiber, the acid used as the sol–gel catalyst, the drying process, and the pyrolysis temperature. Owing to the Yates formula, the optimal conditions leading to an optimized specific surface area (SSA) enhancing lithium-ion diffusion are highlighted. Conclusively, whereas kapok-based carbon and supercritical drying are essential for achieving high SSAs, the effect of pyrolysis temperature on TiO 2 crystallinity depends on the acid-based sol–gel conditions, and to favor anatase instead of rutile, acetic acid should be used. As a result, this method of synthesis and implementation has made it possible to use the most suitable samples without extra conductive carbon as anodes in lithium-ion batteries and their electrochemical characteristics have been obtained using galvanostatic measurements over 40 cycles. Graphical abstrac
Quand et où la localisation échoue : une analyse Iterative Closest Point dans un environnement en évolution
No full textInternational audienceRobust relocalization in dynamic outdoor environments remains a key challenge for autonomous systems relying on 3D lidar. While long-term localization has been widely studied, short-term environmental changes, occurring over days or weeks, remain underexplored despite their practical significance. To address this gap, we present a highresolution, short-term multi-temporal dataset collected weekly from February to April 2025 across natural and semi-urban settings. Each session includes high-density point cloud maps, 360 deg panoramic images, and trajectory data. Projected lidar scans, derived from the point cloud maps and modeled with sensor-accurate occlusions, are used to evaluate alignment accuracy against the ground truth using two Iterative Closest Point (ICP) variants: Point-to-Point and Point-to-Plane. Results show that Point-to-Plane offers significantly more stable and accurate registration, particularly in areas with sparse features or dense vegetation. This study provides a structured dataset for evaluating short-term localization robustness, a reproducible framework for analyzing scan-to-map alignment under noise, and a comparative evaluation of ICP performance in evolving outdoor environments. Our analysis underscores how local geometry and environmental variability affect localization success, offering insights for designing more resilient robotic systems.La relocalisation robuste dans des environnements extérieurs dynamiques reste un défi majeur pour les systèmes autonomes qui s'appuient sur le lidar 3D. Si la localisation à long terme a fait l'objet de nombreuses études, les changements environnementaux à court terme, qui se produisent sur plusieurs jours ou semaines, restent peu explorés malgré leur importance pratique. Pour combler cette lacune, nous présentons un ensemble de données multitemporelles à haute résolution et à court terme, collectées chaque semaine entre février et avril 2025 dans des environnements naturels et semi-urbains. Chaque session comprend des cartes de nuages de points à haute densité, des images panoramiques à 360 degrés et des données de trajectoire. Les scans lidar projetés, dérivés des cartes de nuages de points et modélisés avec des occlusions précises au niveau des capteurs, sont utilisés pour évaluer la précision de l'alignement par rapport à la vérité terrain à l'aide de deux variantes de l'ICP (Iterative Closest Point) : Point-to-Point et Point-to-Plane. Les résultats montrent que Point-to-Plane offre un enregistrement nettement plus stable et précis, en particulier dans les zones à faible densité ou à végétation dense. Cette étude fournit un ensemble de données structuré pour évaluer la robustesse de la localisation à court terme, un cadre reproductible pour analyser l'alignement scan-to-map en présence de bruit, et une évaluation comparative des performances ICP dans des environnements extérieurs en évolution. Notre analyse souligne l'influence de la géométrie locale et de la variabilité environnementale sur la réussite de la localisation, offrant ainsi des informations utiles pour la conception de systèmes robotiques plus résilients
A database to predict safety risks of raw milk cheeses from farming practices in climate change context
No full textInternational audienceIn France over the last decade, respectively 37% and 60% of listeriosis and enterohaemorrhagic E. coli infections outbreaks have been linked to the consumption of raw milk cheeses. In Massif Central, farms of Saint-Nectaire PDO are affected by sanitary alerts per year due to Listeria monocytogenes and Salers PDO farms due to Listeria monocytogenes and E. coli. These alerts occur rarely, or recurrently (more than 2 times/year). Different studies showed that it is today crucial to take a systemic approach to the microbiodiversity of raw milk, from the grassland, through the farming and processing methods, right up to the consumption of the cheese. Consolidated data over years in an adapted database are needed to predict the links between farming practices and sanitary risks in a context of climate change and agricultural practices’ evolutions.A first database prototype was built with the identified variables, including the entity-relationship diagram and a data dictionary. More than 210 variables were identified in farming, milking and cheesemaking practices and grouped into 11 clusters. Each variable was explained by label description, type (numeric, alphanumeric, date), units, modalities, constraints and calculation rules, information source and reliability level. Database queries permitted to describe farm status to date. First multivariate statistical analyses were conducted on the data of 40 PDO’s farms. Data structuring enabled work on single or numerous farming practices scale and their links with sanitary situations. Collected data will aim at being used to build an explanatory model and to establish a multi-criteria ranking in PDOs agricultural systems
“Do I hear south in my voice? I hope not”: Richard Ford’s Frank Bascombe as a hypertextual counterpart to William Faulkner’s Quentin Compson
No full textInternational audienceRichard Ford’s complex relationship with the Southern literary tradition is rooted in his early admiration for Faulkner, whose influence is evident in Ford’s first novel and persists throughout his career despite his deliberate efforts to distance himself from Southern themes. Although Ford relocates his narratives beyond the South, his Frank Bascombe stories reflect a deep transtextual connection to Faulkner, particularly through their parallels with Quentin Compson. This connection manifests not only through allusions but also through parody, as Frank emerges as a hypertextual rewriting of Quentin. Frank’s irony and the narrative fragmentation in both characters ultimately foreground a defamiliarization of Southern identity, underscoring Faulkner’s enduring presence in Ford’s work.La relation complexe qu'entretient Richard Ford avec la tradition littéraire du Sud trouve ses racines dans son admiration précoce pour Faulkner, dont l’influence est manifeste dès son premier roman et perdure tout au long de sa carrière, en dépit de ses efforts délibérés pour s’éloigner des thématiques sudistes. Bien que Ford déplace ses récits en dehors du Sud, ses textes consacrés à Frank Bascombe révèlent un lien transtextuel profond avec Faulkner, notamment à travers leurs parallèles avec le personnage de Quentin Compson. Cette connexion se manifeste non seulement par des allusions, mais également par la parodie, Frank apparaissant comme une réécriture hypertextuelle de Quentin. L’ironie de Frank Bascombe et la fragmentation narrative qui caractérisent les deux figures mettent en lumière une défamiliarisation de l’identité sudiste, soulignant ainsi la présence persistante de Faulkner dans l’œuvre de Ford
Achieving sustainable development and debt sustainability in developing countries: To what extent do debt-for-nature swaps matter?
No full textThis paper assesses the impact of debt-for-nature swaps on sustainable development in developing countries, using entropy balancing on a large sample of 127 countries from 1990 to 2020. The findings indicate that debt-for-nature swaps have a positive and statistically significant effect on sustainable development, operating through several key channels: public debt reduction, increased public investment, lower CO2 emissions, and improved human development. The additional results found in this paper show that if the treated countries had not benefited from debtfor-nature swaps, their sustainable development index would have decreased by 11%.At the same time, if untreated countries had benefited from debt-for-nature swaps, their Sustainable Development Index would have increased by around 2%. The analysis also reveals a non-linear relationship between the size of debt-for-nature swaps and the sustainable development index, with an optimal threshold estimated at 42% of the public debt level, beyond which diminishing returns are observed. These results suggest that debt-for-nature swaps can serve as an effective financing tool for sustainable development, provided that they are appropriately designed. From a policy perspective, expanding debt-for-nature swap programs requires broadening eligibility criteria, strengthening transparency and governance of environmental funds, and more systematically integrating climate objectives into multilateral debt relief mechanisms. Enhanced coordination between public and private creditors, as well as environmental organizations, is also crucial to ensure that debt-for-nature swaps support the ecological transition effectively in the most vulnerable countries.</div
Soft-ECM: An extension of Evidential C-Means for complex data
No full textInternational audienceClustering based on belief functions has been gaining increasing attention in the machine learning community due to its ability to effectively represent uncertainty and/or imprecision. However, none of the existing algorithms can be applied to complex data, such as mixed data (numerical and categorical) or non-tabular data like time series. Indeed, these types of data are, in general, not represented in a Euclidean space and the aforementioned algorithms make use of the properties of such spaces, in particular for the construction of barycenters. In this paper, we reformulate the Evidential C-Means (ECM) problem for clustering complex data. We propose a new algorithm, Soft-ECM, which consistently positions the centroids of imprecise clusters requiring only a semi-metric. Our experiments show that Soft-ECM present results comparable to conventional fuzzy clustering approaches on numerical data, and we demonstrate its ability to handle mixed data and its benefits when combining fuzzy clustering with semi-metrics such as DTW for time series data
A Unified View on Regulation Management in Multi-Agent Systems
No full textInternational audienceRegulating multi-agent system (MAS) to achieve a balance between the autonomy of agents and the control of the system is still a challenge. Regulation management in MAS has been conceptualized from various perspectives in the literature, whose intersections open up a wide range of design options. We propose a unified view on regulation management in MAS that identifies the range of design options with respect to three perspectives: the regulation capabilities, the multi-agent oriented programming dimensions, and the architectural style. We use our unified view to review and classify existing MAS frameworks in the literature, highlighting the dominant and underexplored views on regulation management in MAS
A 13.06 Ma widespread ignimbrite in the Pannonian Basin captured a snapshot of shallow marine to coastal environment in Central Paratethys
No full textInternational audienceVoluminous Miocene silicic volcanism sourced mainly from the extensional Pannonian Basin played a major role in the evolution of the Central Paratethys. Here, we identify a widely distributed (> 3150 km 2 ) member of the Upper Rhyolite Tuff in Hungary, called the Dobi Ignimbrite, with a precise sanidine/plagioclase 40Ar/ 39Ar age of 13.064 ± 0.065 Ma (~ Badenian/Sarmatian boundary in Central Paratethys chronology). It has distinctive glass geochemistry with wide compositional variations, which conforms with large-scale silicic explosive eruptions. In line with this, the calculated minimum volume (~ 200 km 3 ) of the Dobi Ignimbrite is consistent with a high-end VEI 7 eruption, with possible ultradistal transport distance of over 300 km. Most of the pyroclastic succession, which erupted in two phases, was emplaced on land, as it contains leaves and tree trunks in the basal layer that we correlate with the Badenian/Sarmatian ‘volcanic floras’ of northern Hungary. At the same time, the ignimbrite has a strongly phreatomagmatic character, and, together with the presence of free-floating foraminifera, this suggest that the source vent was located in coastal waters of the Central Paratethys. These findings indicate either a late Badenian marine incursion prior to the eruption, or the shift of the eruption center toward the sea
Does index insurance really work for smallholder farmers?
No full textWorld Bank Let's Talk Development BlogIndex insurance products pay out after evaluating a simple external measure, such as rainfall levels. We pool evidence from eight experiments that provide causal evidence on the impact of index insurance programs on productive investments in LMICs. Our findings temper the initial enthusiasm. Recent innovations in the design and implementation of index-based insurance have raised hopes that newer products might address some of the challenges that limit the effectiveness of earlier versions