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La musica sacra di Franchino Gaffurio: Messe, Volume III : Missa De tous biens pleine ; Missa Sexti Toni ; Missa Sanctae Catherinae
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Impact of lymph node staging on survival in presumed early-stage ovarian cancer: a multicentric retrospective study
No full textInternational audienceObjective:This study aimed to assess the impact of comprehensive staging on survival outcomes in this population.Methods:Patients who underwent surgery for epithelial ovarian cancer in one of the 14 Francogyn cancer centers between 2000 and 2020 were included in the study. The primary analysis evaluated the impact of lymphadenectomy on overall survival and recurrence-free survival. Lymph node count was analyzed as a continuous variable, and its association with survival, considered as a continuous outcome was assessed using linear regression (secondary analysis). Survival was compared using the log-rank test, and multivariate analysis was performed using a Cox model.Results:A total of 467 patients with presumed early-stage epithelial ovarian cancer were included, of which 198 underwent complete lymphadenectomy and 266 did not. No significant association was found between lymph node staging and survival in the primary analysis, possibly due to limited statistical power and a selection bias, as patients without lymphadenectomy had more favorable disease profiles (p=0.600 and p=0.700, respectively). Complete lymphadenectomy was associated with a significantly higher risk of complications (34.5% vs. 14%, p<0.001). In secondary analysis, the number of para-aortic lymph nodes harvested was identified as an independent predictor of both overall survival and recurrence-free survival (p=0.007 and p=0.002, respectively). Histological characteristics and adjuvant chemotherapy also showed a significant correlation with improved survival outcomes.Conclusion:Extensive para-aortic lymphadenectomy in early-stage epithelial ovarian cancer is associated with better overall and recurrence-free survival but comes with an increased risk of complications
Flood pulse monitoring in wetlands with multi-temporal Sentinel-1 interferometric coherence data: Application to the Okavango Delta (Botswana)
No full textInternational audienceFlood-pulsed wetlands are characterized by significant seasonal water fluctuations, which play a critical role in the dynamics of these sensitive ecosystems. Among the growing number of existing remote sensing products, we explore the potential of interferometric (InSAR) coherence time series, derived from Sentinel-1 synthetic-aperture radar images, to characterize the hydrological dynamics of the Okavango Delta, a vast flood-pulsed wetland. Interferometric coherence reflects changes in surface conditions, making it a powerful tool for detecting flood propagation. By fitting harmonic functions, we produce parameters that quantify the seasonality of coherence time series with short isotemporal baselines (12 days). In particular, we developed a normalized seasonal index based on the ratio between the seasonal amplitude and the root-mean-square error of the fitted harmonic function, to map the seasonality of the coherence time series. A multi-annual analysis of coherence time series reveals a strong relationship between their seasonality, land cover, and flood frequency. Unsupervised clustering applied to statistical and seasonal metrics of coherence time series yields consistent classifications that map the variability of flood frequencies across wetland areas and clearly distinguish wetlands from dry zones. Similarly thresholds applied to normalized seasonal indices delineate the year-to-year extent of flood pulses with accuracy around 79 %. We show that coherence time series in never flooded areas exhibit a pronounced seasonal pattern driven by rainfall cycle, whereas this seasonality is disrupted by flood pulses in wetlands. Building on this, developed a change-detection approach to map the floods by identifying the date when coherence time series diverge from their seasonal pattern. The resulting flood arrival dates achieve 74–83 % accuracy compared to a reference dataset derived from optical data. Our results highlight the potential of coherence time series as a robust indicator of seasonal variations in inundation extent in flood-pulsed wetlands
Across ancient oceans: Eocene dispersal routes of Asian terrestrial mammals to Europe, Afro-Arabia and South America
No full textInternational audienceDuring the middle and late Eocene, Asian terrestrial mammals dispersed to Europe, while primates and rodents dispersed across the 500-to-2000 km wide Neotethys Ocean and the 1500-to-2000 km wide Atlantic Ocean to colonize Afro-Arabia and South America. This study explores how these mammals have achieved such remarkable and enigmatic dispersals. We present high-resolution paleogeographic models for the middle to late Eocene based on updated plate kinematic reconstructions, paleo-bathymetry and paleo-topography data. With this, we evaluate landmass configurations and connectivity that may have facilitated faunal exchanges from Asia toward Europe, Afro-Arabia, and South America and discuss dispersal mechanisms between these biogeographic provinces. Our reconstructions reveal that during the Bartonian (~40–38 Ma), an overland dispersal corridor between Asia and Balkanatolia became available to terrestrial mammals and acted as a pivotal pathway for Asian faunas dispersing toward western Europe and Afro-Arabia. We identified two Balkanatolian island-hopping routes across the Western Neotethys potentially enabling the dispersal of small-bodied Asian primates, rodents and artiodactyls to Afro-Arabia. Alternatively, these taxa may have rafted across the Central Neotethys. By ~34 Ma, Balkanatolia fully connected with Western Europe, opening a southern “Grande Coupure” route for Asian faunas. In the Atlantic, we identify long-distance rafting as the most plausible mechanism for the 40–34 Ma transoceanic dispersal of the Asian-originated primates and rodents from Afro-Arabia to South America despite the likely presence of sparse islands along the Walvis Ridge and the Rio Grande Rise
: Significations of Landscapes : New Perspectives in the Studies Chinese Iconography,
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Decentralized multi-agent multi-armed bandits for smart electric vehicles charging
No full textInternational audienceSmart charging of electrical vehicles can help in avoiding congestion and peak load demands in an electrical distribution network. On the consumer's side, the advantage lies in minimizing the daily charging cost. He may also benefit from cheap photovoltaic electricity from local sources and therefore reduce his environmental impact. However, this cheaper electricity is variable and uncertain. In many research works, this has been formulated and solved as a centralized or hierarchical optimization problem. However, such systems may suffer from lack of scalability, single point of failures, and privacy breaches. We propose a fully decentralized and fair multi-agent system combined with reinforcement learning called "Decentralised multi-armed bandit (2-armed bandit) based on Thompson sampling"(D-MAB2AB-TS) to control the charging of electrical vehicles under uncertainties. The problem under consideration is formulated as a two-armed bandit (charging or not) for each instant. The proposed algorithm, based on Thompson Sampling, takes into account the uncertainties in the choice of arms combination of other players. The proposed algorithm finds the best combination of arms to play with a computational complexity O(m) linear with the number of arms. The suggested system is also model-free, as it does not assume the model of the environment to be perfectly known, which is a common assumption in many of the existing centralized optimization strategies for smart charging.</div
Components Operationally: Reversibility and System Engineering: Essays Dedicated to Jean-Bernard Stefani on the Occasion of His 65th Birthday
No full textCramér–Rao bound analysis of nested arrays under impulsive noise with coarrays and FLOSs
No full textInternational audienceNested arrays are extensively employed in array signal processing to augment the degrees of freedom and enhance estimation precision, and the Cramér–Rao Bound (CRB) for nested arrays in a Gaussian noise environment has been established. Nevertheless, in a practical wireless communication environment, noise usually exhibits an impulsive characteristic. The impulsive noise applied in a uniform linear array (ULA) has been extensively studied in the literature, but only closed-form expressions of CRB with Cauchy and Gaussian noise distributions are given. Although nested arrays have garnered significant attention recently, research on the CRB under impulsive noise conditions remains scarce. In this paper, we provide the CRB expression for direction of arrival (DOA) estimation with nested arrays in an impulsive noise environment, which indicates that the CRB is formulated in terms of the fractional low-order statistics (FLOSs) of received data. Moreover, we also calculate the CRB results for different FLOSs as well as various sparse arrays and validate that the derived CRB makes an important contribution to the performance analysis of sparse arrays in impulsive noise
Un partage d’expérience autour de la pratique de l’interdisciplinarité sur les feux : le projet EcoSoFI (2022-2024)
No full textInternational audienceLes collaborations inter/transdisciplinaires autour de la compréhension des feux et de leur gestion sont plébiscitées, mais leur mise en œuvre ne va pas pour autant de soi. A partir du partage d’expériences de plusieurs scientifiques et gestionnaires, le présent article restitue la démarche que nous avons adoptée pour comprendre ces difficultés ; et tire quelques constats et propositions. Onconstate notamment la dominance des sciences biophysiques et le poids de la modélisation dans les interfaces entre recherche et gestion. Au sein des SHS, on observe également des partitions entre disciplines et sous-disciplines, ainsi qu’une « interdisciplinarité inachevée » dans l’analyse des changements de régimes de feux. La spécialisation disciplinaire a conduit à une autonomisation du questionnement et des méthodes, qui ne sont plus explicitées ni interrogées au regard des autres approches et du terrain. Nos propositions consistent à remettre en question les catégories implicites concernant les pratiques et les savoirs liés aux feux et à définir des protocoles de recherche permettant des problématisations communes à partir d’études de cas localisées et « concrètes »