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Le « eux » et le « nous » : rapports conflictuels inter-groupes chez les animaux sociaux
No full textInternational audienceOne of the great constants in the history of human societies is the opposition between “us,” which embodies all conceivable positive values, and “them,” which is associated with everything perceived as negative. Contempt or rejection of “the other” (clan, tribe, race, nation, region, class, caste, ethnic or religious group, family) is the principle behind all ethnocentrism. But the opposition between "us" and "them" is only the extension, in the cultural-symbolic order specific to our species, of a general defense mechanism present throughout the animal kingdom, from eusocial insects to primates: defense of the “close” or the “same” (whether related or unrelated) against what is perceived as distant, different, foreign, or outside one's own group. In the case of human societies, “us” and “them” can take very different forms, as groups are built on cultural foundations. While they have succeeded in bringing together millions (even billions) of individuals into coherent and relatively peaceful social units, human societies have constantly multiplied the types of us/them opposition, and therefore the potential conflicts between groups.L'un des grands invariants dans l'histoire des sociétés humaines réside dans l'opposition entre un « nous », chargé de toutes les valeurs positives imaginables, et un « eux », associé à tout ce qui est perçu comme négatif. Le mépris ou le rejet de l'« autre » (clan, tribu, ethnie, race, nation, région, groupe religieux, etc.) est le principe de tout ethnocentrisme. Mais l'opposition eux/nous n'est que le prolongement, dans l'ordre culturel-symbolique propre à notre espèce, d'un mécanisme général de défense présent dans l'ensemble du règne animal, des insectes eusociaux aux primates : défense du « proche » ou du « même » (apparenté ou nonapparenté) par rapport à ce qui est perçu comme lointain, différent, étranger, extérieur à son propre groupe. Dans le cas des sociétés humaines, le « nous » et les « eux » peuvent prendre des formes très variables dans la mesure où les groupes se construisent sur des bases culturelles. En même temps qu'elles ont réussi à rassembler des millions (voire des milliards) d'individus dans des unités sociales cohérentes et relativement pacifiées, les sociétés humaines n'ont cessé de multiplier les types d'opposition eux/nous, et donc les conflits possibles entre les groupes
Uptake of atmospheric pollutants on road asphalt pavements: an underestimated sink in urban environments
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Primordial axisymmetric compact objects in General Relativity
No full textInternational audienceThe search for exact solutions describing asymptotically FLRW compact objects in General Relativity (GR) remains a notoriously challenging problem. To a large extent, progress has been restricted to the spherically symmetric sector, with the exception of the Kerr-de Sitter and Thakhurta solutions. In this work, we present two new results that advance the description of axisymmetric compact objects embedded in a cosmological background. We first introduce a new solution-generating technique allowing one to construct non-stationary and axisymmetric solutions of the self-interacting Einstein-Scalar system. Using this method, we present the first exact solution which describes a dynamical axisymmetric black (or white) hole embedded in an expanding or contracting cosmology. We provide a detailed investigation of its properties, and in particular its dynamical trapping (or anti-trapping) horizons. To that end, we use the mean curvature vector (MCV) which stands as a natural generalization of the Kodama vector beyond spherical symmetry. The norm of this vector provides a foliation-independent quantity to locate the trapped/anti-trapped and untrapped regions and characterize the causal nature of a given geometry without specific symmetry requirement. The solution-generating method and the techniques to analyze the new solutions provide new powerful tools to further explore the description and the phenomenology of dynamical compact objects embedded in cosmology, in particular those of primordial black holes
Neurological and psychiatric issues in 187 adults with early-treated PKU: The ECOPHEN study
No full textInternational audienceIntroduction: Phenylketonuria (PKU) is an autosomal recessive disorder caused by mutations in the PAH gene leading to phenylalanine hydroxylase deficiency. This results in the accumulation of phenylalanine (Phe) in blood and brain, causing neurological and psychiatric impairments if untreated. Newborn screening (NBS) introduced in the 1960s enables early PKU diagnosis, allowing prompt dietary or sapropterin treatment. The long-term outcomes in adults with early-treated PKU, however, may include subtle neurocognitive deficits alongside somatic neurological and psychiatric complications, which remain incompletely characterized. Patients and methods: The ECOPHEN study was a French 5-year multicenter prospective cohort assessing neuropsychiatric disorders in adults with early-treated PKU. Results: Here are presented the data at inclusion. The study recruited 187 patients who were classified by PKU severity-classic, mild, or mild persistent hyperphenylalaninemia-and diet adherence status. Neurological history revealed symptoms in 11.2 % of patients, exclusively in classic PKU, including tremor, migraines, and balance disorders, without significant differences between diet groups. Neurological examination abnormalities predominantly included abnormal deep tendon reflexes in classic PKU patients. Psychiatric issues affected 25.7 % of patients across severity groups, mainly depressive episodes and anxiety, with no clear influence of diet adherence. Discussion/conclusion: The present study highlights neurological complications persisting despite early treatment, particularly in classic PKU. Diet adherence and current plasma Phe levels did not correlate significantly with neurological or psychiatric outcomes, possibly due to suboptimal metabolic control. Limitations included the cross-sectional design, absence of control group, and retrospective data collection. Overall, adults with early-treated PKU show a generally favorable outcome but remain at risk for neuropsychiatric manifestations, supporting the need for lifelong follow-up including neurologic and psychiatric evaluation
Degree bounds for linear differential equations and recurrences
No full textLinear differential equations and recurrences reveal many properties about their solutions. Therefore, these equations are well-suited for representing solutions and computing with special functions. We identify a large class of existing algorithms that compute such representations as a linear relation between the iterates of an elementary operator known as a pseudo-linear map. Algorithms of this form have been designed and used for solving various computational problems, in different contexts, including effective closure properties for linear differential or recurrence equations, the computation of a differential equation satisfied by an algebraic function, and many others. We propose a unified approach for establishing precise degree bounds on the solutions of all these problems. This approach relies on a common structure shared by all the specific instances of the class. For each problem, the obtained bound is tight. It either improves or recovers the previous best known bound that was derived by ad hoc methods
Production of polyhydroxyalkanoates by Halomonas sp. HG01, a halophilic bacterium from northern Peru, using various carbon sources: metabolic and genomic analysis
No full textInternational audienceHalomonas sp. HG01, a moderate halophilic bacterium isolated from a northern Peru salt mine, is promising as a polyhydroxyalkanoate (PHA) producer. Experimental data and genome analysis were used to evaluate its capabilities. Shaken flask experiments revealed that HG01 can accumulate 70-86 wt.% poly(3-hydroxybutyrate) [P(3HB)] from various carbon sources, including glucose, sucrose, and fructose. In a fed-batch bioreactor, it achieved a cell dry weight (CDW) of 12.2 g/L with 63% P(3HB) content after 72 hours. The PHA synthase enzyme exhibited substrate specificity for C4 to C5 compounds. HG01 strain also produced poly(3hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] from propionic and valeric acids, with a maximum 3HV content of 25.53 mol% monomers into the polymer (69.40 %wt) when valeric acid was used. The complete bacterial 3.66 Mbp genome sequence revealed metabolic pathways for carbohydrate and fatty acid catabolism, PHA biosynthesis, and stress tolerance factor. This genetic information enhances our understanding of PHA synthesis and supports the development of metabolic engineering strategies, positioning Halomonas sp. HG01 as a promising candidate for biotechnological applications
Specific killing and resensitization of pathogenic Escherichia coli strains carrying bla CTX-M-15 β-lactamase using targeted-antibacterial-plasmids (TAPs)
No full textInternational audienceAbstract Targeted-Antibacterial-Plasmids (TAPs) offer a precise approach to combat multidrug-resistant bacteria by selectively removing resistant strains while preserving commensals. Here, we assess TAPs that deliver CRISPR/Cas systems via conjugation to kill or resensitize extended-spectrum β-lactamase (ESBL)-producing Escherichia coli carrying the blaCTX-M-15 gene. We systematically tested multiple variables in the TAP approach, including two commensal E. coli donors, three distinct helper plasmids encoding the transfer machineries, and six recipient strains harbouring the resistance gene either chromosomally or on a plasmid. Cas9-based TAPs induced double-stranded breaks in chromosomal blaCTX-M-15 genes, resulting in immediate bacterial death. When the target gene was plasmid-borne, Cas9 cleavage triggered plasmid loss and partial toxin-antitoxin-mediated killing. In contrast, dCas9-based TAPs inhibited blaCTX-M-15 expression without affecting cell viability, thereby restoring third-generation cephalosporin susceptibility. In mixed-culture experiments, TAPs specifically eliminated only blaCTX-M-15-carrying E. coli while sparing other non-targeted bacterial species. Conjugation assays in human faeces demonstrated substantial suppression of cefotaxime-resistant (CtxR) E. coli by both Cas9- and dCas9-based TAPs, underscoring their efficacy in complex microbial environments. These findings highlight TAPs’ decolonization promise, paving the way for future microbiome-editing interventions against multidrug-resistant carriage or infection
Scalable magnetic resonance fingerprinting: Incremental inference of high dimensional elliptical mixtures from large data volumes
No full textInternational audienceMagnetic Resonance Fingerprinting (MRF) is an emerging technology with the potential to revolutionize radiology and medical diagnostics. In comparison to traditional magnetic resonance imaging (MRI), MRF enables the rapid, simultaneous, non-invasive acquisition and reconstruction of multiple tissue parameters, paving the way for novel diagnostic techniques. In the original matching approach, reconstruction is based on the search for the best matches between in vivo acquired signals and a dictionary of high-dimensional simulated signals (fingerprints) with known tissue properties. A critical and limiting challenge is that the size of the simulated dictionary increases exponentially with the number of parameters, leading to an extremely costly subsequent matching. In this work, we propose to address this scalability issue by considering probabilistic mixtures of high-dimensional elliptical distributions, to learn more efficient dictionary representations. Mixture components are modelled as flexible ellipitic shapes in low dimensional subspaces. They are exploited to cluster similar signals and reduce their dimension locally cluster-wise to limit information loss. To estimate such a mixture model, we provide a new incremental algorithm capable of handling large numbers of signals, allowing us to go far beyond the hardware limitations encountered by standard implementations. We demonstrate, on simulated and real data, that our method effectively manages large volumes of MRF data with maintained accuracy. It offers a more efficient solution for accurate tissue characterization and significantly reduces the computational burden, making the clinical application of MRF more practical and accessible
1989 in the East. Between Order and Subversion
No full textApril 15, 2026 by RoutledgeInternational audience1989 in the East revisits the processes that led to the collapse of communist regimes in Central and Eastern Europe, the Balkans and the USSR. This disintegration appeared to be the result of complex mobilisations where the repertoires of action, the institutional and non-institutional ties, the ideological preferences, and the identities of the actors, including the most official ones, have been profoundly changed. The modes of contestation have gone from a self-limited subversion of established institutions, with some forms of collaboration with the regime, to much clearer and more radical forms of head-on opposition. Opposition movements developed according to rhythms and modalities specific to each country, sometimes to each social sphere. Social mobilisations, institutional transformations (both visible and less visible), and the emergence of new actors in all social spheres are therefore central issues in this book.This book, based on rich empirical material, will be of interest to specialists in the region, as well as, more generally, to students of regime change and collapse, political crises, social movements, authoritarian regimes, and the forms of mobilisation that develop within them