Ein neues politisches Koordinatensystem? Die französischen Präsidentschaftswahlen und der Blick auf die Parlamentswahl

Die Wiederwahl Emmanuel Macrons offenbart eine tiefe Spaltung der französischen Gesellschaft. Diese wird vom praktisch verschwunde- nen traditionellen Parteiensystem nicht mehr abgebildet. Stattdessen stehen sich nach der Präsidentschaftswahl drei Lager (Linkspopulisten, liberales Zentrum, Rechtspopulisten) gegenüber. Dieses Novum im bisher bipolaren französischen politischen System wird sich auf die be- vorstehende Parlamentswahl auswirken. Möglicherweise wird Präsident Macron nach der Wahl zwar nicht über eine eigene Mehrheit verfügen, es wird aber auch keine Mehrheit gegen ihn (Cohabitation) geben. Diese Situation wäre ein Novum für das politische System der V. Republik. Die darin zum Ausdruck kommenden gesellschaftlichen Spannungen werden so oder so eine lagerübergreifende Anstrengung zur politischen und gesellschaftlichen Reform erfordern.La réélection d’Emmanuel Macron révèle une profonde division de la so- ciété française. Celle-ci n’est plus représentée par le système de partis traditionnel, qui ont pratiquement disparu. Au lieu de cela, trois blocs (populistes de gauche, centre libéral, populistes de droite) s’affrontent après l’élection présidentielle. Cette transformation du système politique français, jusqu’ici bipolaire, aura des répercussions sur les prochaines élections législatives. Aussi il est possible que le président Macron ne disposera pas d’une majorité propre à l’issue de celles-ci, mais sans qu’une majorité contre lui (cohabitation) soit envisageable. Cette situation serait alors une première pour la Vème République. Les tensions sociales s’exprimant à travers cette situation nécessiteront d’une manière ou d’une autre un effort transcendant les camps pour réformer la politique et la société

Astraeus VII: The environmental-dependent assembly of galaxies in the Epoch of Reionization

Using the ASTRAEUS (semi-numerical rAdiative tranSfer coupling of galaxy formaTion and Reionization in N-body dark matter simUlationS) framework, we explore the impact of environmental density and radiative feedback on the assembly of galaxies and their host halos during the Epoch of Reionization. The ASTRAEUS framework allows us to study the evolution of galaxies with masses ($\rm 10^{8.2}M_\odot < M_{\rm h} < 10^{13}M_\odot$) in wide variety of environment ($-0.5 < {\rm log}(1+\delta) < 1.3$ averaged over $(2~{\rm cMpc})^3$). We find that : (i) there exists a mass- and redshift- dependent "characteristic" environment (${\rm log} (1+\delta_a(M_{\rm h}, z)) = 0.021\times M_{\rm h}^{0.16} + 0.07 z -1.12$, up to $z\sim 10$) at which galaxies are most efficient at accreting dark matter, e.g at a rate of $0.2\%$ of their mass every Myr at $z=5$; (ii) the number of minor and major mergers and their contributions to the dark matter assembly increases with halo mass at all redshifts and is mostly independent of the environment; (iii) at $z=5$ minor mergers contribute slightly more (by up to $\sim 10\%$) to the dark matter assembly while for the stellar assembly, major mergers dominate the contribution from minor mergers for $M_{\rm h}\lesssim 10^{11.5}M_\odot$ galaxies; (iv) radiative feedback quenches star formation more in low-mass galaxies ($M_{\rm h} \lesssim 10^{9.5}M_\odot$) in over-dense environments (${\rm log}(1+\delta) > 0.5$); dominated by their major branch, this yields star formation histories biased towards older ages with a slower redshift evolution.Comment: 17 pages, 15 figures, submitted to MNRAS, comments welcome

Astraeus VIII: A new framework for Lyman-α\alpha emitters applied to different reionisation scenarios

We use the {\sc astraeus} framework to investigate how the visibility and spatial distribution of Lyman-$\alpha$ (Ly$\alpha$) emitters (LAEs) during reionisation is sensitive to a halo mass-dependent fraction of ionising radiation escaping from the galactic environment ($f_\mathrm{esc}$) and the ionisation topology. To this end, we consider the two physically plausible bracketing scenarios of $f_\mathrm{esc}$ increasing and decreasing with rising halo mass. We derive the corresponding observed Ly$\alpha$ luminosities of galaxies for three different analytic Ly$\alpha$ line profiles and associated Ly$\alpha$ escape fraction ($f_\mathrm{esc}^\mathrm{Ly\alpha}$) models: importantly, we introduce two novel analytic Ly$\alpha$ line profile models that describe the surrounding interstellar medium (ISM) as dusty gas clumps. They are based on parameterising results from radiative transfer simulations, with one of them relating $f_\mathrm{esc}^\mathrm{Ly\alpha}$ to $f_\mathrm{esc}$ by assuming the ISM of being interspersed with low-density tunnels. Our key findings are: (i) for dusty gas clumps, the Ly$\alpha$ line profile develops from a central to double peak profile as a galaxy's halo mass increases; (ii) LAEs are galaxies with $M_h\gtrsim10^{10}M_\odot$ located in overdense and highly ionised regions; (iii) for this reason, the spatial distribution of LAEs is primarily sensitive to the global ionisation fraction and only weakly in second-order to the ionisation topology or a halo mass-dependent $f_\mathrm{esc}$; (iv) furthermore, as the observed Ly$\alpha$ luminosity functions reflect the Ly$\alpha$ emission from more massive galaxies, there is a degeneracy between the $f_\mathrm{esc}$-dependent intrinsic Ly$\alpha$ luminosity and the Ly$\alpha$ attenuation by dust in the ISM if $f_\mathrm{esc}$ does not exceed $\sim50\%$.Comment: 25 pages, 9 figures; accepted for publication in MNRA

Astraeus - VI. Hierarchical assembly of AGN and their large-scale effect during the Epoch of Reionization

In this work, the sixth of a series, we use the ASTRAEUS (semi-numerical rAdiative tranSfer coupling of galaxy formaTion and Reionization in N-body dark matter simUlationS) framework to investigate the nature of the sources that reionized the Universe. We extend ASTRAEUS, which already couples a galaxy formation semi-analytical model with a detailed semi-numerical reionization scheme, to include a model for black hole formation, growth, and the production of ionizing radiation from associated AGN (active galactic nuclei). We calibrate our fiducial AGN model to reproduce the bolometric luminosity function at z ~ 5, and explore the role of the resulting AGN population in reionizing the Universe. We find that in all the models yielding a reasonable AGN luminosity function, galaxies dominate overwhelmingly the ionizing budget during the Epoch of Reionization, with AGN accounting for 1-10% of the ionizing budget at z=6 and starting to play a role only below z < 5.Comment: 15+2 pages, 14+1 figures, 1 table. Accepted in MNRA

Optimisation des paramètres d'estampage de renforts secs pour applications composites structuraux

Avec des normes européennes de plus en plus restrictives vis-à-vis des émissions de CO2 [1], l'industrie automobile mènent une véritable politique d'allégement de leurs véhicules [2]. Depuis plusieurs décennies, les matériaux composites représentent une réponse aux problématiques d'allègement de structures. La filière automobile française s'intéresse donc à l'industrialisation de leurs procédés de mises en ?uvre, trop souvent peu répétables et limités aux petites et moyennes séries.   Les procédés de type RTM (Resin tranfert Moulding) permettent la production de matériaux composites hautes performances en grande série tout en garantissant une bonne répétabilité. Habituellement, le procédé RTM est décomposé en deux étapes [3]: Mise en forme de renforts fibreux (semi-produits textiles) ou préformage. Injection de la résine (ou imprégnation) dans la préforme.   L'étape de mise en forme de renforts secs selon la géométrie de la pièce joue influe directement sur les paramètres morphologiques de la préforme (orientation, densité et continuité des renforts) qui ont une incidence directe sur la perméabilité de la préforme et sur le comportement mécanique de la pièce composite finale [4]. Dans le cas de l'industrie automobile grand volume, un des procédés de mise en forme privilégiés est l'estampage. Pour respecter du cahier des charges de la préforme et une bonne répétabilité, une montée en maturité de ce procédé est nécessaire.   Dans ce cadre, l'IRT M2P, un centre de recherche, est appuyé par un consortium de 14 industriels (Arkema, Chomarat, Compose, Coriolis, ESI, Faurecia, Hexion, Hutchinson, Institut de Soudure, Owens Corning, PEI, PSA, Renault, SISE) dans le cadre du projet Fast FORM. Ce projet collaboratif ambitionne de développer les méthodes et technologies nécessaires à la réalisation de préformes à destination de l'industrie automobile : Pour pièces structurales de grandes dimensions Optimisation de l'engagement matière Optimum technico-économique Temps de cycle de 2 min  Dans cette communication, les différents maillons de la démarche de montée en maturité du procédé d'estampage seront présentés :   Caractérisation des renforts : permet de fournir une loi matériaux pour la simulation. Un intérêt particulier est porté sur la caractérisation en cisaillement, qui est considéré comme le mode de déformation prépondérant lors du préformage. L'essai de bias test est notamment simulé pour vérifier la bonne corrélation avec l'expérience. Cette communication s'appuiera sur la caractérisation d'un NCF de verre. Réalisation d'estampages de géométries élémentaires (hémisphères, goussets). Ces essais sont simulés sous PAM FORM (ESI Group [5]). La corrélation expériences / simulations permettra d'ajuster les cartes matériaux et d'identifier les leviers d'optimisation. Itération pour définir une configuration d'estampage optimale pour des pièces complexes de grandes dimensions. Cette phase définit la forme des outils et leur cinématique grâce à la simulation sous PAM FORM. Ces définitions permettent de concevoir et d'industrialiser le procédé. Corrélation simulation-expérience d'estampages de grandes dimensions. Cette phase permet de valider les méthodes et la mise en données de l'étude numérique. Références :   [1] European Commission, Press release: Further CO2 emission reductions from cars and vans: a win-win for the climate, consumers, innovation and jobs. 2012. [2] L. David, ?Stratégie Matériaux Automobile pour les années à venir.? PSA / SRA, 12-Jun-2013. [3] P. Boisse, ?Mise en forme des matériaux fibreux - Tech. ing.? 2004. [4] D. Turner and K. Hjelmstad, ?Determining the 3D permeability of fibrous media using the Newton method,? in Compos. Part B Eng., 2007, pp. 44 ? 57. [5] ?https://www.esi-group.com/fr.?

Differential retention of transposable element-derived sequences in outcrossing Arabidopsis genomes

International audienceBackground: Transposable elements (TEs) are genomic parasites with major impacts on host genome architecture and host adaptation. A proper evaluation of their evolutionary significance has been hampered by the paucity of short scale phylogenetic comparisons between closely related species. Here, we characterized the dynamics of TE accumulation at the micro-evolutionary scale by comparing two closely related plant species, Arabidopsis lyrata and A. halleri. Results: Joint genome annotation in these two outcrossing species confirmed that both contain two distinct populations of TEs with either 'recent' or 'old' insertion histories. Identification of rare segregating insertions suggests that diverse TE families contribute to the ongoing dynamics of TE accumulation in the two species. Orthologous TE fragments (i.e. those that have been maintained in both species), tend to be located closer to genes than those that are retained in one species only. Compared to non-orthologous TE insertions, those that are orthologous tend to produce fewer short interfering RNAs, are less heavily methylated when found within or adjacent to genes and these tend to have lower expression levels. These findings suggest that long-term retention of TE insertions reflects their frequent acquisition of adaptive roles and/or the deleterious effects of removing nearly neutral TE insertions when they are close to genes. Conclusion: Our results indicate a rapid evolutionary dynamics of the TE landscape in these two outcrossing species, with an important input of a diverse set of new insertions with variable propensity to resist deletion

Dispersal syndromes in challenging environments: A cross‐species experiment

Dispersal is a central biological process tightly integrated into life-histories, morphology, physiology and behaviour. Such associations, or syndromes, are anticipated to impact the eco-evolutionary dynamics of spatially structured populations, and cascade into ecosystem processes. As for dispersal on its own, these syndromes are likely neither fixed nor random, but conditional on the experienced environment. We experimentally studied how dispersal propensity varies with individuals' phenotype and local environmental harshness using 15 species ranging from protists to vertebrates. We reveal a general phenotypic dispersal syndrome across studied species, with dispersers being larger, more active and having a marked locomotion-oriented morphology and a strengthening of the link between dispersal and some phenotypic traits with environmental harshness. Our proof-of-concept metacommunity model further reveals cascading effects of context-dependent syndromes on the local and regional organisation of functional diversity. Our study opens new avenues to advance our understanding of the functioning of spatially structured populations, communities and ecosystems. Keywords: context-dependent dispersal; dispersal strategy; distributed experiment; predation risk; resource limitatio

Design, manufacturing and testing of a green non-isocyanate polyurethane prosthetic heart valve.

peer reviewedThe sole effective treatment for most patients with heart valve disease is valve replacement by implantation of mechanical or biological prostheses. However, mechanical valves represent high risk of thromboembolism, and biological prostheses are prone to early degeneration. In this work, we aim to determine the potential of novel environmentally-friendly non-isocyanate polyurethanes (NIPUs) for manufacturing synthetic prosthetic heart valves. Polyhydroxyurethane (PHU) NIPUs are synthesized via an isocyanate-free route, tested in vitro, and used to produce aortic valves. PHU elastomers reinforced with a polyester mesh show mechanical properties similar to native valve leaflets. These NIPUs do not cause hemolysis. Interestingly, both platelet adhesion and contact activation-induced coagulation are strongly reduced on NIPU surfaces, indicating low thrombogenicity. Fibroblasts and endothelial cells maintain normal growth and shape after indirect contact with NIPUs. Fluid-structure interaction (FSI) allows modeling of the ideal valve design, with minimal shear stress on the leaflets. Injection-molded valves are tested in a pulse duplicator and show ISO-compliant hydrodynamic performance, comparable to clinically-used bioprostheses. Poly(tetrahydrofuran) (PTHF)-NIPU patches do not show any evidence of calcification over a period of 8 weeks. NIPUs are promising sustainable biomaterials for the manufacturing of improved prosthetic valves with low thrombogenicity

Global standards of Constitutional law : epistemology and methodology

Just as it led the philosophy of science to gravitate around scientific practice, the abandonment of all foundationalist aspirations has already begun making political philosophy into an attentive observer of the new ways in which constitutional law is practiced. Yet paradoxically, lawyers and legal scholars are not those who understand this the most clearly. Beyond analyzing the jurisprudence that has emerged from the expansion of constitutional justice, and taking into account the development of international and regional law, the ongoing globalization of constitutional law requires comparing the constitutional laws of individual nations. Following Waldron, the product of this new legal science can be considered as ius gentium. This legal science is not as well established as one might like to think. But it can be developed on the grounds of the practice that consists in ascertaining standards. As abstract types of best “practices” (and especially norms) of constitutional law from around the world, these are only a source of law in a substantive, not a formal, sense. They thus belong to what I should like to call a “second order legal positivity.” In this article I will undertake, both at a methodological and an epistemological level, the development of a model for ascertaining global standards of constitutional law