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Redox‐Induced Structural Rearrangement in an M8 L2 Self‐Assembly
No full textInternational audienceAbstract Due to the reversible nature of the metal–ligand bond, coordination cages are inherently dynamic architectures which can undergo structural transformations upon appropriate external stimulations. This adaptability has been widely explored in various fields. Herein, we report the preparation of a redox‐responsive discrete (Ru2)4L2 architecture through a coordination‐driven self‐assembly approach, where Ru2 is a bis(ruthenium(II)) complex and L a tetrapyridyl ligand. Importantly, ligand L is designed around the π‐extended tetrathiafulvalene framework (exTTF), whose geometry is highly sensitive to its redox state. The resulting (Ru2)4L2 assembly was fully characterized, revealing a twisted configuration with two orthogonally oriented L units in close spatial proximity. Remarkably, this assembly undergoes an oxidation‐induced transformation into a (Ru2)4Lox ₂ structure, in which the two dicationic ligands are now spatially separated and aligned according to a face‐to‐face arrangement, affording a cage‐like structure. This reorganization is driven by the redox‐induced geometric and electronic changes of the exTTF cores and the resulting electrostatic repulsions occurring between both oxidized ligands. The process is fully reversible upon chemical reduction, restoring the original (Ru2)4L₂ structure
Superconducting and spin-density wave phases probed by scanning tunneling spectroscopy in the organic conductor
No full textInternational audienc
Sub-game order preservation and values for TU-games
No full textIn cooperative games with transferable utility (TU-games), a player's contribution may vary depending on the coalition they join, reflecting different levels of synergy with other members. In this paper, we introduce a family of axioms referred to as sub-game order preservation axioms, which formalize the intuition that a player's payoff should increase with the degree of synergy they exhibit within a coalition. We propose four distinct axioms, each of which captures a different interpretation of what constitutes synergy in the context of transferable utility. We demonstrate that one of these variants is incompatible with the classical Efficiency axiom, thereby giving rise to an impossibility result. The remaining three axioms, when combined with Efficiency, lead to unique characterizations of three well-known solution concepts: the Shapley value, the Center of the Imputation Set (CIS), and the Equal Allocation of Non-Separable Contributions (ENSC) value, respectively
Antipredator responses of native amphibian tadpoles to the presence of invasive alien African clawed frogs
No full textInternational audienceBiological invasions are a primary driver of global environmental changes. Invasive alien species can affect ecosystem dynamics, including interspecific relationships such as competition and predation. Although widely recognized, the impacts of invasive predators on native prey remain sparsely documented, particularly in amphibians. African clawed frog, Xenopus laevis, which is native to South Africa, has successfully established populations in western France and has expanded its range in recent decades. African clawed frog is known to prey on native amphibians; however, the indirect effects of predation risk remain unknown. Using 10 min video recordings, whether Pelophylax spp. tadpoles, which is a native frog common in French wetlands, showed antipredator responses to the invasive African clawed frog was tested. These responses were compared with those to other predators, including native Odonata larvae and alien red swamp crayfish, Procambarus clarkii. Native tadpoles displayed the greatest distance from the predator, and they were more aggregated (with a smaller nearest neighbour distance) when exposed to African clawed frogs compared with other predators. However, the time individuals spent swimming and exploring as well as the average speed during exploration did not differ among predators. This study focuses on the ability of native tadpoles to recognize and respond to invasive predators, emphasizing the ecological challenges faced by native populations.</div
Detection of Somatic Copy Number Alterations from Single-cell Multiomics Data With the R Package muscadet
No full textInternational audienceBackground. Cancer drug resistance emerges from the evolution of tumor cells, driven by genet-ic (e.g., somatic mutations, copy number alterations (CNAs)) and non-genetic (e.g., chromatin modifications) mechanisms that confer survival advantages under treatment pressure. Single-cell multiomics enables the detailed study of these processes by capturing genomic and epigenomic changes at cellular resolution. However, existing CNA detection tools are restricted to a single omic type, missing the opportunity to leverage integrated information from multiomics da-tasets. To address this limitation, we developed muscadet, an R package that integrates multiple single-cell modalities for more accurate CNA detection.Results. We applied the muscadet framework to matched pre- and post-treatment multiple my-eloma patient samples, integrating whole-genome sequencing (WGS), single-cell transcriptomic (scRNA-seq), and single-cell chromatin accessibility (scATAC-seq) data. By combining these modal-ities, muscadet enhances CNA detection and subclonal characterization with greater resolution. It outperforms existing single omic approaches by refining CNA identification, capturing tumor heterogeneity, and enabling the tracking of genomic and epigenomic changes in response to therapies.Conclusions. Our findings demonstrate the advantages of integrating single-cell multiomics for a refined characterization of tumor evolution. The R package muscadet provides a robust compu-tational framework for CNA detection, providing deeper insights into clonal dynamics and facili-tating the identification of therapeutic vulnerabilities
Les acteurs religieux dans la redéfinition du pouvoir politique et de l'espace public à Tivaouane, Sénégal
No full textInternational audienceLa communication interroge l'influence des acteurs du religieux dans la reconfiguration de l’espacepublic et du pouvoir politique local à Tivaouane. Au Sénégal, cette ville sainte de la confrérie soufieTidjaniyya, connaît chaque année des rassemblements religieux d’envergure dont le Gamou est le plus emblématique. Dépassant la seule dimension spirituelle pour devenir des moments d’affirmation identitaire et d’expression religieuse et politique, ces événements permettent aux groupes sociaux et religieux de se rencontrer, se confronter et de redéfinir la gouvernance de la ville. Initialement fête traditionnelle, le gamou est devenu musulman au début du XXe siècle avecl'installation d'Elhadj Malick Sy à Tivaouane. Depuis, chaque année, des milliers de personnes ycélèbrent la naissance du prophète Mouhammad. Bien qu’unificateur, le Gamou est aussi le théâtrede tensions et de divisions intra et interconfrériques.Par exemple le Dahiratoul Moustarchidine Wal Moustarchidaty, scission confrérique tidjane, utilisel'hippodrome de Tivaouane comme lieu alternatif de rassemblement depuis les années 1980. Cetespace symbolise la contestation et l’affirmation identitaire face à la branche principale de laTidjaniyya. La bipolarisation du Gamou interroge quant aux relations entre sphères religieuses etpolitiques. L’organisation et la manifestation de ce grand événement illustrent la manière dont lesautorités religieuses redéfinissent leur pouvoir et leur identité dans l’espace public.Tivaouane est à la fois une ville religieuse et une commune juridique. Ce double statut engendre unegouvernance complexe. Les nombreux acteurs religieux, politiques et associatifs y interviennent, avec parfois des chevauchements ou « dépassements de fonction ». Par exemple, l’association COSKAS a pris une dimension politique majeure, influençant les politiques locales et nationales. Les groupes religieux redéfinissent ainsi les rapports sociaux et renforcent leur capital symbolique en s'engageant dans la sphère publique, souvent au détriment de l'État.Nous présenterons donc ici le contexte d’étude en articulant la singularité de Tivaouane autour duGamou. Nous montrerons comment cette fête rassemble et révèle des divergences entre les groupesreligieux. Enfin, nous aborderons la gouvernance complexe de la ville, résultat d’un double statutautour duquel composent de nombreux acteurs. Ces derniers y jouent un rôle crucial dans lareconfiguration de l’espace public, de la gouvernance et des rapports de pouvoir, avec desrépercussions importantes sur la société sénégalaise
Exploring the spatial segmentation of housing markets from online listings
No full text9 pages, 10 figuresInternational audienceThe real estate market shows an inherent connection to space. Real estate agencies unevenly operate and specialize across space, price and type of properties, thereby segmenting the market into submarkets. We introduce here a methodology based on multipartite networks to detect the spatial segmentation emerging from data on housing online listings. Considering the spatial information of the listings, we build a bipartite network that connects agencies and spatial units. This bipartite network is projected into a network of spatial units, whose connections account for similarities in the agency ecosystem. We then apply clustering methods to this network to segment markets into spatially-coherent regions, which are found to be robust across different clustering detection algorithms, discretization of space and spatial scales, and across countries with case studies in France and Spain. This methodology addresses the long-standing issue of housing market segmentation, relevant in disciplines such as urban studies and spatial economics, and with implications for policymaking
An inverse Gaussian process with bathtub-shaped degradation rate function in the presence of random effect and measurement error
No full textInternational audienceThis paper proposes a new inverse Gaussian process with bathtub-shaped degradation rate function, which can account for the joint presence of random effect and measurement error. The distinguishing feature of the proposed model is its ability to describe degradation processes that present a change point, here intended as the point where the bathtub-shaped degradation rate function passes from the decreasing to the increasing phase. Maximum likelihood estimates of the parameters of the model are computed by adopting in a combined manner an expectation-maximization algorithm and a particle filter method. The same particle filter is also used to estimate the mean remaining useful life and to detect the change point. The model is applied to a set of real degradation data of five MOSFETs. Obtained results demonstrate the utility and the affordability of the proposed approach