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Global Roadkill Data: a dataset on terrestrial vertebrate mortality caused by collision with vehicles
No full textInternational audienceRoadkill is widely recognized as one of the primary negative effects of roads on many wildlife species and also has socioeconomic impacts when they result in accidents. A comprehensive dataset of roadkill locations is essential to evaluate the factors contributing to roadkill risk and to enhance our comprehension of its impact on wildlife populations and socioeconomic dimensions. We undertook a compilation of roadkill records, encompassing both published and unpublished data gathered from road surveys or opportunistic sources. GLOBAL ROADKILL DATA includes 208,570 roadkill records of terrestrial vertebrates from 54 countries across six continents, encompassing data collected between 1971 and 2024. This dataset serves to minimise the collection of redundant data and acts as a valuable resource for local and macro scale analysis regarding rates of roadkill, road-and landscape-related features associated with risk of roadkill, vulnerability of species to road traffic, and populations at risk of local extinction. The objective of this dataset is to promote scientific progress in infrastructure ecology and terrestrial vertebrate conservation while limiting the socio-economic costs
Role of trophic interactions in transfer and cascading impacts of plant protection products on biodiversity: a literature review
No full textInternational audiencePlant protection products (PPPs) have historically been one of the classes of chemical compounds at the frontline of raising scientific and public awareness of the global nature of environmental pollution and the role of trophic interactions in shaping the impacts of chemicals on ecosystems. Despite increasingly strong regulatory measures since the 1970s designed to avoid unintentional effects of PPPs, their use is now recognised as a driver of biodiversity erosion. The French Ministries for the Environment, Agriculture and Research commissioned a collective scientific assessment to synthesise the current science and knowledge on the impacts of PPPs on biodiversity and ecosystem services. Here we report a literature review of the state of knowledge on the propagation of PPP residues and the effects of PPPs in food webs, including biopesticides, with a focus on current-use PPPs. Currently used PPPs may be stronger drivers of the current biodiversity loss than the banned compounds no longer in use, and there have been far fewer reviews on current-use PPPs than legacy PPPs. We first provide a detailed overview of the transfer and propagation of effects of PPPs through trophic interactions in both terrestrial and aquatic ecosystems. We then review cross-ecosystem trophic paths of PPP propagation, and provide insight on the role of trophic interactions in the impacts of PPPs on ecological functions. We conclude with a summary of the available knowledge and the perspectives for tackling the main gaps, and address areas that warrant further research and pathways to advancing environmental risk assessment
A brief review on models for birds exposed to chemicals
No full textInternational audience“A Who’s Who of pesticides is therefore of concern to us all. If we are going to live so intimately with these chemicals eating and drinking them, taking them into the very marrow of our bones - we had better know something about their nature and their power.”—Rachel Carson, Silent Spring. In her day, Rachel Carson was right: plant protection products (PPP), like all the other chemical substances that humans increasingly release into the environment without further precaution, are among our worst enemies today (Bruhl and Zaller, 2019; Naidu et al., 2021; Tang et al., 2021; Topping et al., 2020). All compartments of the biosphere, air, soil and water, are potential reservoirs within which all species that live there are impaired. Birds are particularly concerned: PPP are recognized as a factor in the decline of their abundance and diversity predominantly in agricultural landscapes. Due to the restrictions on vertebrates testing, in silico-based approaches are an ideal choice alternative given input data are available. This is where the problem lies as we will illustrate in this paper. We performed an extensive literature search covering a long period of time, a wide diversity of bird species, a large range of chemical substances, and as many model types as possible to encompass all our future need to improve environmental risk assessment of chemicals for birds. In the end, we show that poultry species exposed to pesticides are the most studied at the individual level with physiologically based toxicokinetic models. To go beyond, with more species, more chemical types, over several levels of biological organization, we show that observed data are crucially missing (Gilbert, 2011). As a consequence, improving existing models or developing new ones could be like climbing Everest if no additional data can be gathered, especially on chemical effects and toxicodynamic aspects
Value of information in the conservation of a heritage cello: An info-gap decision theory approach
No full textInternational audienceDecision-making for the conservation of heritage stringed musical instruments, especially their playing conditions, can be supported by science-based models. Mechanical stresses induced by string tension can prevent an instrument from being played if the risk of damage is too high since they can lead to plastic strains and permanently damage a rare object. Science-based modeling tools, such as the finite element method, require detailed knowledge of the mechanical and material properties of the instrument. However, many of these properties are uncertain, such as material properties, relative humidity conditions, or existing crack defects. Info-gap decision theory provides a framework to address uncertainty and to evaluate the robustness of decisions in situations where there are significant gaps in information. This is applied here to the decision-making process to determine whether an instrument is playable or not an antique cello by Pietro Guarneri, E.1555, kept in the Musée de la musique-philharmonie de Paris. The instrument shows local damage from insect galleries. The decision that needs to be made is whether or not the instrument can be played without damaging it. The info-gap robustness metric evaluates how wrong our physics-based model can be with respect to the baseline material properties without jeopardising the validity of this decision. Toward this end, a finite element model is created and a static analysis is performed to compute the stress field near the damaged area resulting from string tension. A robustness analysis is performed to compute the info-gap robustness curves for different uncertainty scenarios with respect to both the elastic properties and the yield stresses of wood with unknown properties. In this illustration, it is shown that it is more effective to reduce uncertainty in the elastic properties rather than yield stresses to ensure a robust decision concerning the playability of the instrument
Au-delà de la superposition et de l’effondrement : interférences à double fente issues des géodésiques d’un espace-temps frémissant
No full textDas Doppelspalt-Experiment wurde lange Zeit als Beleg für die Welle-Teilchen-Dualität und die quantenmechanische Superposition interpretiert. Hier schlagen wir eine deterministische Alternative vor, die auf der Theorie der zitternden Raumzeitrelativität (TSRT) basiert, in der Teilchen stets lokalen Geodäten der Eigenzeit innerhalb einer kausal strukturierten, aber metrisch fluktuierenden Raumzeit folgen. Die beobachteten Interferenzmuster entstehen nicht durch Superposition von Wellenfunktionen, sondern durch die deterministische Umlenkung von Teilchengeodäten infolge von Krümmungsstörungen, die durch die Geometrie der Spalte bestimmt werden. Die Verteilung der Ankunftspositionen wird durch zwei geometrische Mechanismen gesteuert: (i) den Spaltabstand, der den Winkelbereich der abgelenkten Geodäten festlegt, und (ii) eine minimale Wirkungsschwelle, die eine Auflösungsgrenze auf Basis kausaler Unterscheidbarkeit erzwingt. Das Plancksche Wirkungsquantum ergibt sich auf natürliche Weise aus dieser kausalen Schranke als kleinster auflösbarer Unterschied in der Geodätenwirkung – ganz ohne quantenmechanische Postulate. Die TSRT liefert analytische Vorhersagen für die Interferenzabstände und Intensitätsverteilungen bei einer Vielzahl von Teilchen – Photonen, Elektronen und Neutronen – durch Anwendung geometrischer Ablenkungsgesetze auf kausal zulässige Geodäten. Diese Vorhersagen stimmen eng mit etablierten experimentellen Ergebnissen überein. Darüber hinaus ermöglicht der TSRT-Rahmen die Simulation beliebiger Konfigurationen durch Modellierung von Geodäten-Ensembles unter metrischem Zittern und stellt damit eine vollständig geometrische Alternative zur quantenmechanischen Superposition dar.The double-slit experiment has long been interpreted as evidence of wave-particle duality and quantum superposition. Here we propose a deterministic alternative rooted in Trembling Spacetime Relativity Theory (TSRT), where particles always follow localized proper-time geodesics within a causally structured but metrically fluctuating spacetime. Apparent interference fringes arise not from wavefunction superposition, but from the deterministic redirection of particle geodesics due to curvature perturbations shaped by the slit geometry. The observed distribution of arrival positions is governed by two geometric mechanisms: (i) the slit separation, which sets the angular deflection range of redirected geodesics, and (ii) a minimal action threshold that enforces a resolution limit based on causal distinguishability. Planck’s constant emerges naturally from this causal constraint as the smallest resolvable geodesic action difference, without any quantum postulates. TSRT provides analytical predictions for fringe spacing and intensity distribution across a wide range of particles—photons, electrons, and neutrons—by applying geometric deflection laws to causally permitted geodesics. These predictions align closely with established experimental results. In addition, the TSRT framework enables simulation of arbitrary configurations by modeling ensembles of geodesics subject to metric trembling, providing a fully geometric alternative to quantum superposition.Durante mucho tiempo, el experimento de la doble rendija ha sido interpretado como evidencia de la dualidad onda-partícula y de la superposición cuántica. Aquí proponemos una alternativa determinista basada en la Teoría de la Relatividad del Espaciotiempo Tembloroso (TSRT), en la cual las partículas siguen siempre geodésicas localizadas de tiempo propio dentro de un espaciotiempo estructurado causalmente pero con fluctuaciones métricas. Las franjas de interferencia no surgen de la superposición de funciones de onda, sino de la redirección determinista de las geodésicas de las partículas debido a perturbaciones de la curvatura moldeadas por la geometría de las rendijas. La distribución observada de las posiciones de llegada está gobernada por dos mecanismos geométricos: (i) la separación entre rendijas, que determina el rango de desviación angular de las geodésicas redirigidas, y (ii) un umbral mínimo de acción que impone un límite de resolución basado en la distinguibilidad causal. La constante de Planck surge de manera natural de esta restricción causal como la menor diferencia de acción geodésica resoluble, sin recurrir a postulados cuánticos. TSRT proporciona predicciones analíticas para el espaciamiento de las franjas y la distribución de intensidad en una amplia gama de partículas —fotones, electrones y neutrones— aplicando leyes de desviación geométrica a geodésicas permitidas causalmente. Estas predicciones concuerdan estrechamente con los resultados experimentales establecidos. Además, el marco de TSRT permite simular configuraciones arbitrarias mediante el modelado de conjuntos de geodésicas sujetas a temblores métricos, ofreciendo así una alternativa completamente geométrica a la superposición cuántica.L’expérience des deux fentes est depuis longtemps interprétée comme une preuve de la dualité onde-corpuscule et de la superposition quantique. Nous proposons ici une alternative déterministe fondée sur la théorie de la relativité de l’espace-temps frémissant (TSRT), dans laquelle les particules suivent toujours des géodésiques locales de temps propre au sein d’un espace-temps causalement structuré mais soumis à des fluctuations métriques. Les franges d’interférence observées ne résultent pas d’une superposition de fonctions d’onde, mais d’une redirection déterministe des géodésiques de particules, induite par les perturbations de courbure façonnées par la géométrie des fentes. La distribution spatiale des positions d’arrivée est gouvernée par deux mécanismes géométriques : (i) la séparation entre les fentes, qui fixe la plage angulaire des géodésiques redirigées, et (ii) un seuil d’action minimale imposant une limite de résolution fondée sur la distinguabilité causale. La constante de Planck émerge naturellement de cette contrainte causale comme la plus petite différence d’action géodésique résoluble, sans aucun postulat quantique. La TSRT fournit des prédictions analytiques de l’espacement des franges et de la distribution d’intensité pour une large gamme de particules — photons, électrons et neutrons — en appliquant des lois de déviation géométrique aux géodésiques causalement permises. Ces prédictions concordent étroitement avec les résultats expérimentaux établis. De plus, le cadre TSRT permet de simuler des configurations arbitraires en modélisant des ensembles de géodésiques soumises à des tremblements métriques, offrant ainsi une alternative entièrement géométrique à la superposition quantique
Study of genetic diversity of Echinococcus granulosus sensu stricto in France based on full cox1 gene
No full textInternational audienceCystic echinococcosis (CE) is a worldwide zoonosis caused by Echinococcus granulosus sensu lato (s.l.) complex with E. granulosus sensu stricto (s.s.) the main species responsible of humans CE. This study highlights the genetic diversity of E. granulosus s.s. in France to clarify the parasite's circulation in livestock, interactions with wildlife, and distinguish autochthonous from imported cases of human CE. A total of 129 full cox1 gene sequences were obtained: 101 from livestock, 12 from wildlife, and 16 from human CE patients operated in France. This study reveals a broad genetic diversity of E. granulosus s.s. in France and little differentiation between sheep and cattle parasite populations, or between geographic areas. The G3 genotype (67 %) was predominant, mainly in sheep from the Alps, a historical focus in Southeast France. Despite farms being less than 20 km apart, no common haplotype was found, suggesting separate infections sources, without excluding the potential role of transhumance in parasite transmission. Haplotypes shared by livestock and wolves remain insignificant in maintaining the life cycle given the low occurrence of infection in wolves. Concerning the 16 cases of human CE, full cox1 haplotypes provide additional genetic argument supporting their status as mainly imported cases. Nevertheless, as autochthonous human cases have already been reported, further genetic characterization of E. granulosus s.s. in both humans and livestock in France is important to identify epidemiologic links and develop action plans to prevent and control this parasite
Articuler trame verte et bleue et planification : quelle intégration de la connectivité écologique dans les Schémas de Cohérence Territoriale en région Bourgogne Franche-Comté ?
No full textInternational audienceL’intégration de la Trame Verte et Bleue (TVB) dans la planification territoriale suppose de considérer conjointement les différents enjeux territoriaux et la connectivité écologique. Cette recherche examine les discours relatifs à la TVB et propose un cadre d’analyse des documents de planification en s’appuyant sur un corpus de données textuelles et visuelles issues des Schémas de Cohérence Territoriale (SCoT) approuvés en région Bourgogne Franche-Comté. L’analyse combine une analyse lexicométrique et une analyse qualitative. Les résultats montrent que la TVB est appréhendée sous différents angles se rapportant à ses dimensions fonctionnelle et territoriale, et révèlent la présence d’un flou autour du principe de connectivité écologique
Exploring the taxonomic status of the Palearctic cone weevil, Pissodes validirostris, inferred from morphometric and molecular data
No full textInternational audienceThe Scots pine cone weevil, Pissodes validirostris Gyll. (Coleoptera: Curculionidae) widely distributed from Europe, across to North-Eastern China, consumes the cones of Mediterranean pines, as well those of the sylvestris section. The use of multiple host pine species with limited and patchy distributions, combined with low dispersal rates, likely contributed to significant genetic and morphological variation among P. validirostris populations in its native range. P. validirostris is being considered as a biological control agent for wilding pines in the southern hemisphere and for this programme to proceed, elucidating its intraspecific variability is necessary. This study aimed to explore the phylogeography of P. validirostris in its native range in Europe using mitochondrial and nuclear genetic markers as well as morphological characters. The integrative taxonomic analysis revealed high genetic structuring in P. validirostris populations, identifying three main phylogeographic clades: Clade A (Iberian Peninsula, associated with Pinus pinaster and Pinus halepensis ), Clade B (Central Europe), and Clade C (Northern and Eastern Europe), both associated with Pinus species of the sylvestris section. The morphometric data showed that adults of the Iberic Peninsula clade were significantly larger than those of the two others. When compared to other Nearctic and Palearctic congeneric species, P. validirostris formed a monophyletic group, likely consisting of different evolutionary lineages within the sampled distribution. The findings highlight the necessity of genetic confirmation for insect taxonomy across wide distributions or multiple host trees. Clarifying whether host specificity or geography drives P. validirostris population structuring will facilitate the selection of a specific clade for wilding pine biological control
Physics-Informed Neural Network for modeling and predicting temperature fluctuations in proton exchange membrane electrolysis
No full textInternational audienceProton Exchange Membrane (PEM) electrolysis stands as a cornerstone technology in the clean energy sector, driving the production of hydrogen and oxygen from water. A critical aspect of ensuring the efficiency and safety of this process lies in the precise monitoring and control of temperature at the electrolysis outlet. However, accurately characterizing temperature changes within the PEM electrolysis system can be challenging due to the fluctuation of renewable energies. This study introduces an approach integrating data with fundamental physics principles known as Physics-Informed Neural Networks (PINNs). This method solves differential equations and estimates the unknown parameters governing the temperature dynamics within the PEM electrolysis system. We consider two distinct scenarios: a zero-dimensional model and a one-dimensional model. The results demonstrate the PINN’s proficiency in accurately identifying the parameters and solving for temperature fluctuations within the system with different input conditions. Furthermore, we compare the PINN with the Long Short-Term Memory (LSTM) method to predict the outlet temperature of the electrolysis. The PINN outperformed the LSTM method, highlighting its reliability and precision, achieving a Mean Squared Error (MSE) of 0.1596 compared to 1.2132 for LSTM models. The proposed method shows a high performance in dealing with sensor noises and avoids overfitting problems. This synergy of physics knowledge and data-driven learning opens new pathways towards real-time digital twins, enhanced predictive control, and improved reliability for PEM electrolysis and other complex, data-scarce energy systems
On-Surface Synthesis Guided by Supramolecular Orientation on an Au(111) Surface
No full textNational audienceAmong all the proposed precursors for creating 2D covalent networks, the molecule 1,3,5-tris(4'- bromophenyl)benzene (TBB) stands out as the most extensively examined molecule under ultra-high vacuum conditions using scanning tunneling microscopy (UHV-STM). This star-shaped molecule features three branches, each terminating with a bromine atom, and it serves as the prototype for generating a conjugated 2D network containing hexagonal pores.1 We have demonstrated the existence of a novel supramolecular self-assembly resulting from the deposition of TBB molecules on the Au(111) surface. This self-assembly is guided by a triple halogen bond, locally forming an X3-synthon. Halogen interactions are stronger compared to other no-covalent interactions, and the network remains stable up to temperatures of 373 K. By adjusting the annealing temperature to 383 K, we have demonstrated the formation of 1D sawtooth-like polymers through an Ullmann-like cross-coupling process. These 1D covalent networks are highly ordered and nearly defect-free, thanks to the initial supramolecular network geometry, which promotes the propagation of polymerization at low temperatures to limit excessive precursor diffusion. This result highlights the potential for controlling surface polymerization and achieving defect-free conjugated nanostructures guided by supramolecular orientation. Ongoing work is focused on optimizing polymerization conditions to produce longer polymer chains