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Deciphering copper and zinc leaching from antifouling paints with different operating modes: flux determination and toxicity evidence
No full textInternational audienceLaboratory experiments were performed using 3 antifouling paints with different operating modes immersed in seawater for 7 days, to estimate copper and zinc fluxes and determine the scale of the related contamination. The toxicity of antifouling paints leachates was also assessed for natural bacterioplanktonic and phytoplanktonic communities. Given the increase in copper and zinc concentrations (4 to 1750-fold enrichment in dissolved Cu and to 7 to 200-fold enrichment in dissolved Zn), a systematic mortality upon phytoplankton was evidenced within 2 days of exposure to leachates produced from 1 hour to 2 days of immersion, whatever the paint. This went oppositely with the environmental risks calculated according to European guidelines, demonstrating an acceptable risk for the environment. Considering that 1 hour of leaching from a 7 cm² painted disk polluted 0.5L of seawater with Cu in our experimental conditions whatever the paint used, we estimated that a painted ship hull of 15 m² can pollute more than 10 m 3 of seawater within the same time. Leachates produced after only 20 minutes even yielded phytoplankton growth inhibition or mortality for insoluble and self-polishing paints, respectively, shortening the time needed for a freshly painted ship hull of 15 m² to pollute 10 m 3 . The bacterioplanktonic community appeared less sensitive than phytoplankton but demonstrated the same hierarchy: the highest toxicity was observed for the insoluble matrix and the lowest toxicity for the soluble one. This study therefore brings added value in terms of biocides flux determination, range of studied paints and concrete toxicity evaluation
Mythes millénaristes et rites eschatologiques en Mélanésie: John Frum et le sauvetage de la coutume à Tanna (Vanuatu)
No full textA l'occasion de cette deuxième séquence de la journée portant sur les perspectives anthropologiques et ethnographiques des messianismes et millénarismes contemporains, ma présentation vise à apporter des éléments de réponse à deux questions. Qu'est-ce que l'anthropologie du Pacifique a apporté à l'étude du millénarisme ? Qu'est ce que j'ai moi-même apportée à l'étude d'un des plus célèbres mouvements millénaristes de cette région, le mouvement John Frum à Tanna ? C'est de manière fortuite que les ethnologues océanistes se sont confrontés au thème du millénarisme. Leur intérêt initial portait sur une problématique plus large, celle des changements sociaux engendrés par l'effet du contact culturel. Les travaux d'un FE Williams en Papouasie dans les années 1930 sur les mouvements sociaux nés de la présence missionnaire et de l'adaptation au christianisme de communautés locales inaugurèrent un sujet historiquement majeur pour l'étude des transformations culturelles dans le Pacifique, à savoir la thématique des « cultes du Cargo ». Ces mouvements sont venus rappeler aux nombreux chercheurs qui les ont abordés, la place du religieux dans les dynamiques du changement social et culturel. Dans le contexte historique de la christianisation des populations du Pacifique, le processus intensif d'imposition des nouvelles croyances a notamment consisté pour ces peuples en leur découverte du dogme monothéiste, impliquant notamment une profonde remise en question de leurs représentations sotériologiques traditionnelles. Tout mythe et toute représentation religieuse, comme le faisaient observer Henry Hubert et Marcel Mauss, semblent s'insérer dans un temps suspendu, se situer hors du temps, bien que le temps soit une condition nécessaire à l'efficience du mythe par la fixation temporelle de la totalité d'une période ou d'un cycle, d'une séquence narrative pensée en terme chronologique. Contrairement au rite pour qui cette détermination est centrale, la localisation temporelle du mythe est minimaliste, placée au début (mythe cosmogonique) ou plus rarement à la fin des temps (mythe eschatologique). Les mythes pourraient ainsi être considérés comme une expression parmi d'autres d'une conception spirituelle de l'éternité, s'ils n'étaient pas sujets à un processus singulier : leur « rajeunissement »
Atmospheric aerosol light scattering and absorption properties in the urban area of Milan (Italy): A focus on aerosol typing
No full textInternational audienc
Measurement of differential -channel single top (anti)quark production cross-sections at 13 TeV with the ATLAS detector
No full textInternational audienceThe production of single top quarks and top antiquarks via the -channel exchange of a virtual boson is measured in proton-proton collisions at a centre-of-mass energy of 13 TeV at the Large Hadron Collider. The full Run 2 data sample recorded with the ATLAS detector in the years 2015-2018 is used, corresponding to an integrated luminosity of 140 fb. The absolute and normalised production cross-sections are measured differentially as a function of the transverse momentum and absolute rapidity of the top quark and top antiquark. In addition, the ratio of top quark to top antiquark production cross-sections is measured. The measured distributions are compared with next-to-leading-order quantum chromodynamics predictions obtained with different combinations of matrix-element generators, parton-shower programs and proton parton distribution functions, as well as to next-to-next-to-leading-order calculations. Overall, good agreement is observed between the measurements and the theoretical predictions. For most measured distributions, the sensitivity to differences between the predictions is limited by the systematic uncertainties in the measurement. The measured differential distributions are also interpreted in an effective field theory approach to constrain the Wilson-Coefficient associated with a four-quark operator. The interpretation accounts for the effect of the selection efficiency, which is altered significantly by non-zero contributions from
Patrick Geddes on Sustainable City Life
No full textInternational audienceThis article reinterprets Sir Patrick Geddes's work to illuminate contemporary challenges in sustainable urban logistics from a service-oriented perspective. Analysis of his two major works shows that Geddes viewed the city as a living organism, structured around essential logistical operations-supply, production, distribution, and disposal-that are inseparable from daily urban life. Such perspective is placed in dialogue with research on urban metabolism and sustainable supply chains, highlighting the limitations of approaches focused solely on carbon reduction. The analysis arguments that disconnections between logistical infrastructures, inhabited spaces, and social practices undermine urban coherence and generate social tensions often hidden by algorithmic optimization. Revisiting Geddes's Place-Work-Folk triad emphasizes the strategic value of integrating collective vitality, functional proximity, and social cohesion into urban logistics and service systems. Geddes's insights, though sometimes overlooked, provide a robust theoretical framework for designing sustainable service networks that align operational efficiency with social and territorial value creation
Good quantum codes with addressable and parallelizable non-Clifford gates
No full textIn this work, we prove that for any m > 1, there exists a family of good qudit quantum codes supporting transversal logical C m-1 Z gates that can address specified logical qudits and be largely executed in parallel. Building on the family of good quantum error-correcting codes presented in [HVWZ25a], which support addressable and transversal logical CCZ gates, we extend their framework and show how to perform large sets of gates in parallel. The construction relies on the classical algebraic geometry codes of Stichtenoth [Sti06]. Our results lead to a substantial reduction in the depth overhead of multi-control-Z circuits. In particular, we show that the minimal depth of any logical C m-1 Z circuit involving qudits from m distinct code blocks is upper bounded by O(k m-1 ), where k is the code dimension. While this overhead is optimal for dense C m-1 Z circuits, for sparse circuits we discuss how the depth overhead can be significantly reduced by exploiting the structure of the quantum code
Linear Flows on Translation Prisms
No full textInternational audience57 pages, 6 figures, additional figures and a SageMath notebook included in ancillary file
Connecting mitochondrial metabolism and mitotic fidelity to control vulnerability of high grade serous ovarian cancer patients to taxane-based chemotherapy
No full textHigh-grade serous ovarian carcinoma (HGSOC), which accounts for approximately 75% of ovarian cancer cases, is associated with poor clinical outcome. Although most patients initially achieve a complete response to conventional chemotherapy, HGSOC almost invariably develops chemoresistance. There is therefore an urgent need to identify predictive biomarkers of treatment response. Here, through integrative analyses of molecular and clinical data from HGSOC patient cohorts, we identify syntabulin (SYBU), a microtubule-associated protein originally described as a regulator of mitochondrial transport along neuronal microtubules, as a critical determinant of chemosensitivity in HGSOC. Low SYBU expression in tumors correlates with higher tumor grade and increased aggressiveness, yet paradoxically with enhanced sensitivity to chemotherapy. SYBU-deficient cancer cells display impaired oxidative phosphorylation and a metabolic shift toward glycolysis characteristic of the Warburg effect, together with mitotic defects such as chromosome lagging that promote aneuploidy. Mechanistically, syntabulin forms a complex with the mitochondrial outer membrane porin VDAC1 and the inner membrane protein MIC60, a major regulator of mitochondrial cristae organization. Functionally, the syntabulin-MIC60 axis controls cristae architecture and mitotic fidelity, thereby connecting mitochondrial metabolism to cell division. These findings highlight new therapeutic vulnerabilities to overcome chemoresistance in ovarian cancer. SIGNIFICANT STATEMENT Ovarian cancer remains the deadliest gynecologic malignancy, largely due to the systematic emergence of resistance to chemotherapy. Identifying molecular mechanisms involved in response to treatment is therefore a major clinical challenge. Here, we uncover an unexpected role for the mitochondrial protein syntabulin in regulating chemotherapy sensitivity in high-grade serous ovarian cancer. We demonstrate that syntabulin coordinates cancer cell mitotic progression with mitochondrial structure and metabolism through interactions with cristae-shaping proteins. These findings reveal a previously unrecognized link between mitotic regulation and mitochondrial architecture, and identify syntabulin as a potential therapeutic target in ovarian cancer to induce vulnerability to taxane-based chemotherapy
Prediction of hydrogen–ammonia blends autoignition
No full textInternational audienceThe growing interest in hydrogen as an alternative energy vector has raised new technological challenges, in particular regarding its storage. This has motivated increasing attention to ammonia as a hydrogen carrier. In parallel, the use of hydrogen-ammonia blends as combustible fuels has attracted significant interest, as such mixtures can be easier to handle in some applications than pure hydrogen, while still enabling carbon-free combustion.In this context, the present study focuses on modeling the ignition of arbitrary gaseous hydrogen-ammonia-air blends. First, the minimal chemical description required to accurately capture the ignition delay of these mixtures is identified, revealing three main ignition regimes. Ignition delay formulas are then derived for these regimes by extending methods previously developed for pure hydrogen and syngas. The resulting ignition time expressions are subsequently combined into a unified formulation, valid across a wide range of pressures, temperatures, and fuel compositions. Finally, modifications to a recently published passive scalar model for CFD tools are introduced so as to accurately predict ignition events in hydrogen-ammonia-air mixtures while reducing computational cost. Novelty an
