Digging deeper: deep joint species distribution modeling reveals environmental drivers of Earthworm Communities

International audienceEarthworms are key drivers of soil function, influencing organic matter turnover, nutrient cycling, and soil structure. Understanding the environmental controls on their distribution is essential for predicting the impacts of land use and climate change on soil ecosystems. While local studies have identified abiotic drivers of earthworm communities, broad-scale spatial patterns remain underexplored. We developed a multi-species, multi-task deep learning model to jointly predict the distribution of 77 earthworm species across metropolitan France, using historical (1960–1970) and contemporary (1990–2020) records. The model integrates climate, soil, and land cover variables to estimate habitat suitability. We applied SHapley Additive exPlanations (SHAP) to identify key environmental drivers and used species clustering to reveal ecological response groups. The joint model achieved high predictive performance (TSS >0.7) and improved predictions for rare species compared to traditional species distribution models. Shared feature extraction across species allowed for more robust identification of common and contrasting environmental responses. Precipitation variability, temperature seasonality, and land cover emerged as dominant predictors of earthworm distribution but differed in ranking across species and functional groups. Species clustering into response groups to climatic, land use and soil revealed distinct ecological strategies including a gradient of sensitivity to precipitation seasonality, differential habitat preferences in terms of vegetation cover and wetness and trade-offs between soil acidity and organic matter quality. Our study advances both the methodological and ecological understanding of soil biodiversity. We demonstrate the utility of interpretable deep learning approaches for large-scale soil fauna modeling and provide new insights into earthworm habitat specialization. These findings highlight land cover and seasonal climate variability as efficient proxies for soil biodiversity, providing actionable indicators for global monitoring initiatives and helping to identify habitat requirements of earthworm species to guide emerging earthworm conservation strategies in the face of global environmental change

On design, analysis, and hybrid manufacturing of microstructured blade-like geometries

International audienceWith the evolution of new manufacturing technologies such as multi-material 3D printing, one can think of new type of objects that consist of considerably less, yet heterogeneous, material, consequently being porous, lighter and cheaper, while having the very same functionality as the original object when manufactured from one single solid material. We aim at questioning five decades of traditional paradigms in geometric CAD and focus at new generation of CAD objects that are not solid, but contain heterogeneous free-form internal microstructures. We propose a unified manufacturing pipeline that involves all stages, namely design, optimization, manufacturing, and inspection of microstructured free-form geometries. We demonstrate our pipeline on an industrial test case of a blisk blade that sustains the desired pressure limits, yet requires significantly less material when compared to the solid counterpart

Input-to-state stability of infinite-dimensional systems: Foundations and present-day developments

International audienceInput-to-state stability (ISS) unifies the stability and robustness in one notion, and serves as a basis for broad areas of nonlinear control theory. In this contribution, we covered the most fundamental facts in the infinite-dimensional ISS theory with a stress on Lyapunov methods. We consider various applications given by different classes of infinite-dimensional systems. Finally, we discuss a Lyapunov-based small-gain theorem for stability analysis of an interconnection of two ISS systems

Les frontières étatiques face aux dynamiques contestataires. Identités, territoires, pratiques et discours

This issue aims to study the contestation of borders not only through the lens of political power, but by prioritizing the analysis of the logics and strategies of non-state actors, their discourses and claims, and their modes of organization and mobilization. Rather than focusing on macro-level analyses, this issue seeks to question the logics and dynamics that underpin these contestations from a more micro-level perspective. The temporal framework considered covers the long nineteenth, twentieth, and twenty-first centuries.ce numéro cherchera à étudier la contestation des frontières non seulement à travers le prisme du pouvoir politique mais en privilégiant l’analyse des logiques et des stratégies des acteurs non-étatiques, de leurs discours et revendications, des modalités d’organisation et de mobilisation. L’ambition de ce numéro consiste moins à centrer les analyses d’un point de vue macro qu'à s'interroger sur les logiques et les dynamiques qui traversent ces contestations, à partir d’une perspective plutôt micro. Le cadre temporel envisagé correspond à la longue durée des XIXème, XXème et XXIème siècles

Emissions pricing instruments with intermittent renewables: Second-best policy

International audienceI analyze emissions pricing to support the integration of prevailing renewable resources into an electricity mix composed of polluting technologies. I consider the intermittent nature of the resources such as wind energy and externalities due to emissions-intensive production. I show that an emissions tax is inefficient when consumers are on flat-rate electricity tariffs and do not necessarily adapt their consumption to varying production. The tax is inefficient even with flexibility in the markets when consumers are on variable tariffs. The renewable resource induces variability in the polluting electricity production and associated marginal damage that is not efficiently internalized by a predetermined tax. I then study an Emissions Trading Scheme that provides flexibility at the policy level: emissions permits are traded at market prices. Since the emissions cap must still be predetermined, I show that it leads to inefficient permit prices as they do not match the marginal damages. The two emissions pricing instruments are not necessarily equivalent since I find that the tax differs from the prices of permits

Improved Riemannian potato field: an Automatic Artifact Rejection Method for EEG

International audienceElectroencephalography (EEG) signal cleaning has long been a critical challenge in the research community. The presence of artifacts can significantly degrade EEG data quality, complicating analysis and potentially leading to erroneous interpretations. While various artifact rejection methods have been proposed, the gold standard remains manual visual inspection by human experts—a process that is time-consuming, subjective, and impractical for large-scale EEG studies. Existing techniques are often hindered by a strong reliance on manual hyperparameter tuning, sensitivity to outliers, and high computational costs. In this paper, we introduce the improved Riemannian Potato Field (iRPF), a fast and fully automated method for EEG artifact rejection that addresses key limitations of current approaches. We evaluate iRPF against several state-of-the-art artifact rejection methods, using two publicly available EEG databases, labeled for various artifact types, comprising 226 EEG recordings. Our results demonstrate that iRPF outperforms all competitors across multiple metrics, with gains of up to 22% in recall, 102% in specificity, 54% in precision, and 24% in F1-score, compared to Isolation Forest, Autoreject, Riemannian Potato, and Riemannian Potato Field, respectively. Statistical analysis confirmed the significance of these improvements (p < 0.001) with large effect sizes (Cohen’s d > 0.8) in most comparisons. Additionally, on a typical EEG recording iRPF performs artifact cleaning in under 8 milliseconds per epoch using a standard laptop, highlighting its efficiency for large-scale EEG data processing and real-time applications. iRPF offers a robust and data-driven artifact rejection solution for high-quality EEG pre-processing in brain-computer interfaces and clinical neuroimaging applications

Mythologies of Exile

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Intermediation Platforms and Geopolitical Asymmetries, Lessons from a Pandemic

International audienceTo a large extent, and particularly before vaccines became available, human societies owed their resilience during the COVID-19 pandemic to non-pharmaceutical interventions, i.e. social distancing combined with more invasive digital systems. In this paper, we consider the digital applications developed during 2020-2021, the two first years of the pandemic. We introduce a typology based on the services offered and the data flows they require, between both public and private actors. A detailed timeline of these developments shows that countries’ strategies have evolved in strong coherence with their overall digital policy. Our study demonstrates that this exogenous crisis has reinforced the critical role of intermediation platforms for maintaining society’s essential functions. Their increased centrality has contributed to intensifying information asymmetries and power imbalances, already at stake before the pandemic, both between platforms and states, as well as between countries, leading to new geopolitical equilibria

Exner diagnosis method for two-fluid morphodynamics simulations

International audienceMass balance in sediment transport is often associated with single-phase flow model through the resolution of the Exner equation. In this contribution, the mass balance is derived from the two-phase flow, two-fluid, model equations and compared with the conventional single-phase flow approach. Five terms are identified from the two-phase flow formulation: the bed evolution, the storage evolution, the lateral flux, the bed flux and the top flux. Three different flow configurations with increasing complexity are tested, namely a one dimensional pure sedimentation, a two dimensional scour downstream an apron and a three dimensional scour around a vertical square cylinder. The mass balance formulation identifies the driving process of an erosion or a deposition process in each case. This approach can be applied on other configurations related with sediment flux and morphology bed evolution such as scour process

Zeuxis redivivus. Art et émulation dans l’Europe du XVe au XVIIe siècle

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