Global Europe

Nicolas Levrat realiza un recorrido histórico por la conformación del Instituto Europeo y su relación con el proyecto de integración de la Unión Europea, primero Comunidad Económica y posteriormente ampliada a Unión Política. Los principales trazos del Instituto hasta su integración en la Universidad de Ginebra propician un conjunto de actividades tendientes a un proyecto intelectual-político y cultural más amplio

Curves are algebraic K(π,1)K(\pi,1): theoretical and practical aspects

We prove that any geometrically connected curve $X$ over a field $k$ is an algebraic $K(\pi,1)$, as soon as its geometric irreducible components have nonzero genus. This means that the cohomology of any locally constant constructible \'etale sheaf of $\mathbb{Z}/n\mathbb{Z}$-modules, with $n$ invertible in $k$, is canonically isomorphic to the cohomology of its corresponding $\pi_1(X)$-module. To this end, we explicitly construct some Galois coverings of $X$ corresponding to Galois coverings of the normalisation of its irreducible components. When $k$ is finite or separably closed, we explicitly describe finite quotients of $\pi_1(X)$ that allow to compute the cohomology groups of the sheaf, and give explicit descriptions of the cup products $H^1\times H^1\to H^2$ and $H^1\times H^2\to H^3$ in terms of finite group cohomology.Comment: Added explicit construction of covers of nodal curves and cup-product computations for curves over finite field

Türkçe ve Fransızcanın bilgisayar ortamında gösterimi açısından farklılıkların incelenmesi

National audienc

Dried chicory root (Cichorium intybus L.) as a natural fructan source in rabbit diet: effects on growth performance, digestion and caecal and carcass traits

[EN] Three experimental diets were formulated including (per kg) 100 g oats (control diet), 50 g chicory root (Chicory 5 diet) or 100 g chicory root (Chicory 10 diet) at the expense of oats. The diets differed with respect to starch and fructan contents. In the performance trial, 120 Hyplus rabbits were randomly allocated to three groups (two rabbits per cage) and fed one of the three experimental diets between 31 and 73 days of age. At the end of the trial period, 20 rabbits per treatment were slaughtered and used for evaluation of carcass traits. In addition, the coefficients of total tract apparent digestibility (CTTAD) of the diets and caecal traits were determined from 45 to 49 days of age in 10 rabbits per treatment. The diets did not differ significantly in terms of weight gain, feed intake, feed conversion ratio, health status or carcass traits of rabbits. The CTTADs of crude protein (P=0.041) and ether extract (P=0.006) were lower in rabbits fed the Chicory 10 diet than in rabbits fed the control diet. The CTTAD of starch (P<0.001) was lower, whereas that of fructans (P<0.001) higher, in rabbits fed the diets based on chicory root. The caecum weight (P=0.037), the weight of its contents (P=0.025) and the lactic acid (P=0.028) concentration were higher in rabbits fed the Chicory 10 diet than in control rabbits. On the contrary, rabbits fed with the chicory diets showed lower caecal pH (P=0.048) than rabbits fed the control diet. There was a tendency towards a lower caecal dry matter content and higher total VFA concentration in rabbits fed the chicory diets. It may be concluded that chicory root can serve as a natural source of inulin-type fructans in rabbit feed. Diet supplementation with 10% dried chicory root beneficially affected the caecal fermentative activity in the rabbits, without significant reductions in the nutritive value of the diet, growth performance or carcass quality.Financial support for this study was provided by the institutional research project MZE 0002701404Volek, Z.; Marounek, M. (2011). Dried chicory root (Cichorium intybus L.) as a natural fructan source in rabbit diet: effects on growth performance, digestion and caecal and carcass traits. World Rabbit Science. 19(3):143-150. https://doi.org/10.4995/wrs.2011.850SWORD14315019

A possible involvement of endogenous polyamines in the TNF-α cellular sensitivity

AbstractA critical step in the cytotoxic action mechanism of tumor necrosis factor-α (TNF-α) involves, among mitochondrial dysfunctions, an early change of the inner membrane permeability displaying the characteristics of permeability transition. Cytosolic polyamines, especially spermine, are known to inhibit it. Our results show that spermine is only detectable in the TNF-α resistant C6 cells while N1-acetylspermidine is present in the TNF-α sensitive WEHI-164 cells, and putrescine and spermidine are found in both. TNF-α treatment does not change this distribution but only induces a quantitative alteration in TNF-α sensitive cells. Omission of glutamine (energetic substrate) from the culture media alters neither the TNF-α responsiveness of both cell lines nor their polyamine distributions, only their quantitative polyamine contents

Using Text Segmentation to Enhance the Cluster Hypothesis

An alternative way to tackle Information Retrieval, called Passage Retrieval, considers text fragments independently rather than assessing global relevance of documents. In such a context, the fact that relevant information is surrounded by parts of text deviating from the interesting topic does not penalize the document. In this paper, we propose to study the impact of the consideration of these text fragments on a document clustering process. The use of clustering in the field of Information Retrieval is mainly supported by the cluster hypothesis which states that relevant documents tend to be more similar one to each other than to non-relevant documents and hence a clustering process is likely to gather them. Previous experiments have shown that clustering the first retrieved documents as response to a user’s query allows the Information Retrieval systems to improve their effectiveness. In the clustering process used in these studies, documents have been considered globally. Nevertheless, the assumption stating that a document can refer to more than one topic/concept may have also impacts on the document clustering process. Considering passages of the retrieved documents separately may allow to create more representative clusters of the addressed topics. Different approaches have been assessed and results show that using text fragments in the clustering process may turn out to be actually relevant

Methodology for assessing system performance loss within a proactive maintenance framework

Maintenance plays now a critical role in manufacturing for achieving important cost savings and competitive advantage while preserving product conditions. It suggests moving from conventional maintenance practices to predictive strategy. Indeed the maintenance action has to be done at the right time based on the system performance and component Remaining Useful Life (RUL) assessed by a prognostic process. In that way, this paper proposes a methodology in order to evaluate the performance loss of the system according to the degradation of component and the deviations of system input flows. This methodology is supported by the neuro-fuzzy tool ANFIS (Adaptive Neuro-Fuzzy Inference Systems) that allows to integrate knowledge from two different sources: expertise and real data. The feasibility and added value of such methodology is then highlighted through an application case extracted from the TELMA platform used for education and research

Capitalisation et réutilisation avec des patrons dans un cadre d'Ingénierie Système Basée sur les Modèles (ISBM)

International audienceIn order to promote capitalization and reuse within a Model-Based System Engineering (MBSE) framework, this paper proposes a methodological approach that relies on the concept of pattern in order to encapsulate the know-how to be capitalized and reused. Indeed, formalizing and maintaining know-how within a company is essential in order to have a common base of "good practices" available to all engineering teams. To do this, it is necessary to undertake a capitalization process in order to encapsulate these practices. However, it is equally important to make this know-how available and to facilitate its reuse so that engineers can adapt it to their needs. The flexibility of patterns during reuse is an advantage that will contribute to the efficiency of MBSE and where engineering teams are able to rely on the company's know-how

Physics of Polariton Condensates in GaN-based Planar Microcavities

Since its prediction in 1996 by Imamo&#287;lu and coworkers, the use of a non-equilibrium polariton condensate to produce an intense coherent light source referred to as a polariton laser has attracted a lot of interest in the whole physics community as it should allow the realization of ultralow threshold coherent light-emitting devices due to the release of the Bernard-Duraffourg condition. Excitons-polaritons, admixed particles resulting from the strong coupling between a cavity photon and an exciton, are the eigenmodes of a strongly coupled microcavity and exhibit a very light effective mass at the center of the Brillouin zone (105 times lighter that a free electron) inherited from the cavity photon. In the present work, we are interested in III-nitride based microcavities embedding GaN quantum wells in the active region. Thanks to the stability of the excitons at room temperature in this system and a large oscillator strength, polariton condensation has been observed up to 340K under optical excitation, paving the way toward the realization of the first electrically injected polariton laser. The goal of the present study is to provide a detailed analysis of the system properties accounting for nitride specificities, to describe the mechanisms leading to the formation of polariton condensates and to give the key elements for the optimization of devices relying on polariton nonlinearities. For this purpose, a Fourier-imaging setup allowing for the simultaneous monitoring of real space and far-field energy dispersions was carefully designed to operate in the UV spectral range in order to probe the sample emission at various temperatures. The first main result of this thesis is the establishment of the complete polariton phase diagram of our multiple quantum well-based GaN microcavity, which provides a comprehensive tool to favor or inhibit the condensation threshold by adjusting the microcavity parameters. The condensation is shown to be governed either by the kinetics or by the thermodynamics depending on the strength of the interactions. As polaritons are half-light, half-matter particles, the mechanisms leading to the nonlinear threshold are totally different from those of a conventional semiconductor laser. In particular, the possibility to tune the interactions in the system by changing the photonic fraction of the polaritons or the lattice temperature allows discriminating between different relaxation regimes. Then the spin of the polariton condensate is discussed. It is shown that the dimensionality of the system plays a major role in the polarization state of the emitted light. In particular above threshold, for a bulk microcavity, the polarization is randomly oriented whereas for a GaN multiple quantum well based microcavity, the polarization is pinned by the system anisotropy originating from the static disorder. With increasing pumping power, a depinning of the polarization is observed resulting in a progressive decrease in the polarization degree of the emitted light. These two results are well accounted for by a stochastic model of the condensate formation taking into account the in-plane anisotropy caused by the stationary photonic disorder, the self-induced Larmor precession of the condensate pseudospin and the interplay between energy and polarization relaxation rates. In the last part of this work, the case of nonpolar m-plane GaN based microcavities is addressed. In these structures, the optical axis lies in the plane of the cavity leading to a twofold anisotropy: the birefringence is responsible for the anisotropy of the cavity mode and the distribution of the exciton oscillator strength causes different coupling constants between light and matter along the two orthogonal directions. In such structures different selection rules and optical constants for light polarization perpendicular and parallel to the optical axis can lead to the coexistence of weak and strong coupling regimes with a transition to nonlinear emissions