Intégration des immigrés et associations en France. Un essai d'approche croisée par l'économie et la géographie

Documents de travail du Centre d'Economie de la Sorbonne 2015.01 - ISSN : 1955-611XInternational audienceThe issue of integration is key in the literature about migration. It refers to a set of public policies aiming at integrating foreign populations in a given society. This paper aims at investigating the relationships between the integration of four communities installed in France (Algerian, Portugese, Turkish, and Vietnamese) and the presence of associations. The methodology is rooted on two approaches, quantitative economics and geography. It uses a new database, extracted from the Journal Officiel and several surveys, noticeably TeO. In a first step we ask whether the regional distribution and the density of associations explain the degree of integration of the migrants stemming from the four communities. In a second step we test whether memberships into an association increases or decreases the adoption of oppositional identities and if the latter influences the integration via the access to employment.Le thème de l'intégration est un des principaux angles d'attaque de la littérature scientifique consacrée à l'immigration. Il désigne un ensemble de politiques mises en œuvre par les pouvoirs publics pour que des populations soient correctement insérées dans une société donnée. Dans cet article, l'objectif est de voir s'il existe une relation entre l'intégration des personnes appartenant à quatre communautés présentes en France (Algériens, Portugais, Turcs, Vietnamiens) et l'existence d'associations. La méthode repose sur le croisement d'une approche géographique et d'une approche économique, en mobilisant des données inédites issues du Journal Officiel et de plusieurs enquêtes démographiques, notamment l'enquête TeO. On tente de voir d'abord si les variations régionales de la densité des réseaux associatifs communautaires explique la plus ou moins grande intégration des immigrés de ces quatre groupes. Ensuite, en utilisant plusieurs modèles, on tente de voir si l'appartenance à une ou à des associations non communautaires renforce l'adhésion des immigrés à des valeurs oppositionnelles au modèle culturel du pays d'accueil et si cela a une influence au moins indirecte sur leur intégration par l'accès à l'emploi

Boolean networks synchronism sensitivity and XOR circulant networks convergence time

In this paper are presented first results of a theoretical study on the role of non-monotone interactions in Boolean automata networks. We propose to analyse the contribution of non-monotony to the diversity and complexity in their dynamical behaviours according to two axes. The first one consists in supporting the idea that non-monotony has a peculiar influence on the sensitivity to synchronism of such networks. It leads us to the second axis that presents preliminary results and builds an understanding of the dynamical behaviours, in particular concerning convergence times, of specific non-monotone Boolean automata networks called XOR circulant networks.Comment: In Proceedings AUTOMATA&JAC 2012, arXiv:1208.249

Anode supported single chamber solid oxide fuel cells operating in exhaust gases of thermal engine

International audienceThis project deals with the development and the electrochemical characterization of anode supported single chamber SOFC in a simulated environment of thermal engine exhaust gas. In the present work, a gas mixture representative of exhaust conditions is selected. It is composed of hydrocarbons (HC: propane and propene), oxygen, carbon monoxide, carbon dioxide, hydrogen and water. Only oxygen content is varied leading to different gas mixtures characterized by three ratios R = HC/O2. Concerning the cell components, a cermet made of nickel and an electrolyte material, Ce0.9Gd0.1O1.95 (CGO) is used as anode and two cathode materials, La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF) and Pr2NiO4+δ (PNO), are evaluated. The prepared cells are investigated in the various gas mixtures for temperatures ranging from 450 °C to 600 °C. Ni-CGO/CGO/LSCF-CGO cell has delivered a maximum power density of 15 mW cm−2 at 500 °C with R = HC/O2 = 0.21, while lower power densities are obtained for the other ratios, R = 0.44 and R = 0.67. Afterwards, LSCF and PNO cathode materials are compared and LSCF is found to deliver the highest power densities. Finally, by improving the electrolyte microstructure, some cells presenting a maximum power density of 25 mW cm−2 at 550 °C are produced. Moreover, up to 17% of initial HC are eliminated in the gas mixture

The behaviour of dark matter associated with 4 bright cluster galaxies in the 10kpc core of Abell 3827

Galaxy cluster Abell 3827 hosts the stellar remnants of four almost equally bright elliptical galaxies within a core of radius 10kpc. Such corrugation of the stellar distribution is very rare, and suggests recent formation by several simultaneous mergers. We map the distribution of associated dark matter, using new Hubble Space Telescope imaging and VLT/MUSE integral field spectroscopy of a gravitationally lensed system threaded through the cluster core. We find that each of the central galaxies retains a dark matter halo, but that (at least) one of these is spatially offset from its stars. The best-constrained offset is 1.62+/-0.48kpc, where the 68% confidence limit includes both statistical error and systematic biases in mass modelling. Such offsets are not seen in field galaxies, but are predicted during the long infall to a cluster, if dark matter self-interactions generate an extra drag force. With such a small physical separation, it is difficult to definitively rule out astrophysical effects operating exclusively in dense cluster core environments - but if interpreted solely as evidence for self-interacting dark matter, this offset implies a cross-section sigma/m=(1.7+/-0.7)x10^{-4}cm^2/g x (t/10^9yrs)^{-2}, where t is the infall duration.Comment: 15 pages, 9 figure

Amino Acid Substitutions That Affect Receptor Binding and Stability of the Hemagglutinin of Influenza A/H7N9 Virus.

Receptor-binding preference and stability of hemagglutinin have been implicated as crucial determinants of airborne transmission of influenza viruses. Here, amino acid substitutions previously identified to affect these traits were tested in the context of an A/H7N9 virus. Some combinations of substitutions, most notably G219S and K58I, resulted in relatively high affinity for α2,6-linked sialic acid receptor and acid and temperature stability. Thus, the hemagglutinin of the A/H7N9 virus may adopt traits associated with airborne transmission.HHS | NIH | National Institute of Allergy and Infectious Diseases (NIAID) provided funding to Eefje J. A. Schrauwen, Mathilde Richard, David Burke, Sander Herfst, and Ron A. M. Fouchier under grant number HHSN272201400008C. EU FP7 provided funding to Eefje J. A. Schrauwen, Mathilde Richard, Guus F Rimmelzwaan, Sander Herfst, and Ron A. M. Fouchier under grant number 278976 (7th Framework Programme ANTIGONE).This is the author accepted manuscript. The final version is available from the American Society for Microbiology via http://dx.doi.org/10.1128/JVI.03052-1

Gut microbiota imbalance and colorectal cancer.

International audienceThe gut microbiota acts as a real organ. The symbiotic interactions between resident micro-organisms and the digestive tract highly contribute to maintain the gut homeostasis. However, alterations to the microbiome caused by environmental changes (e.g., infection, diet and/or lifestyle) can disturb this symbiotic relationship and promote disease, such as inflammatory bowel diseases and cancer. Colorectal cancer is a complex association of tumoral cells, non-neoplastic cells and a large amount of micro-organisms, and the involvement of the microbiota in colorectal carcinogenesis is becoming increasingly clear. Indeed, many changes in the bacterial composition of the gut microbiota have been reported in colorectal cancer, suggesting a major role of dysbiosis in colorectal carcinogenesis. Some bacterial species have been identified and suspected to play a role in colorectal carcinogenesis, such as Streptococcus bovis, Helicobacter pylori, Bacteroides fragilis, Enterococcus faecalis, Clostridium septicum, Fusobacterium spp. and Escherichia coli. The potential pro-carcinogenic effects of these bacteria are now better understood. In this review, we discuss the possible links between the bacterial microbiota and colorectal carcinogenesis, focusing on dysbiosis and the potential pro-carcinogenic properties of bacteria, such as genotoxicity and other virulence factors, inflammation, host defenses modulation, bacterial-derived metabolism, oxidative stress and anti-oxidative defenses modulation. We lastly describe how bacterial microbiota modifications could represent novel prognosis markers and/or targets for innovative therapeutic strategies

Loss of hepatic DEPTOR alters the metabolic transition to fasting

Objective The mechanistic target of rapamycin (mTOR) is a serine/threonine kinase that functions into distinct protein complexes (mTORC1 and mTORC2) that regulates growth and metabolism. DEP-domain containing mTOR-interacting protein (DEPTOR) is part of these complexes and is known to reduce their activity. Whether DEPTOR loss affects metabolism and organismal growth in vivo has never been tested. Methods We have generated a conditional transgenic mouse allowing the tissue-specific deletion of DEPTOR. This model was crossed with CMV-cre mice or Albumin-cre mice to generate either whole-body or liver-specific DEPTOR knockout (KO) mice. Results Whole-body DEPTOR KO mice are viable, fertile, normal in size, and do not display any gross physical and metabolic abnormalities. To circumvent possible compensatory mechanisms linked to the early and systemic loss of DEPTOR, we have deleted DEPTOR specifically in the liver, a tissue in which DEPTOR protein is expressed and affected in response to mTOR activation. Liver-specific DEPTOR null mice showed a reduction in circulating glucose upon fasting versus control mice. This effect was not associated with change in hepatic gluconeogenesis potential but was linked to a sustained reduction in circulating glucose during insulin tolerance tests. In addition to the reduction in glycemia, liver-specific DEPTOR KO mice had reduced hepatic glycogen content when fasted. We showed that loss of DEPTOR cell-autonomously increased oxidative metabolism in hepatocytes, an effect associated with increased cytochrome c expression but independent of changes in mitochondrial content or in the expression of genes controlling oxidative metabolism. We found that liver-specific DEPTOR KO mice showed sustained mTORC1 activation upon fasting, and that acute treatment with rapamycin was sufficient to normalize glycemia in these mice. Conclusion We propose a model in which hepatic DEPTOR accelerates the inhibition of mTORC1 during the transition to fasting to adjust metabolism to the nutritional status. Keywords: DEPTOR; mTOR; Liver; Glucose; Fastin

Automated Analysis of Flow Cytometry Data to Reduce Inter-Lab Variation in the Detection of Major Histocompatibility Complex Multimer-Binding T Cells

Manual analysis of flow cytometry data and subjective gate-border decisions taken by individuals continue to be a source of variation in the assessment of antigen-specific T cells when comparing data across laboratories, and also over time in individual labs. Therefore, strategies to provide automated analysis of major histocompatibility complex (MHC) multimer-binding T cells represent an attractive solution to decrease subjectivity and technical variation. The challenge of using an automated analysis approach is that MHC multimer-binding T cell populations are often rare and therefore difficult to detect. We used a highly heterogeneous dataset from a recent MHC multimer proficiency panel to assess if MHC multimer-binding CD8+ T cells could be analyzed with computational solutions currently available, and if such analyses would reduce the technical variation across different laboratories. We used three different methods, FLOw Clustering without K (FLOCK), Scalable Weighted Iterative Flow-clustering Technique (SWIFT), and ReFlow to analyze flow cytometry data files from 28 laboratories. Each laboratory screened for antigen-responsive T cell populations with frequency ranging from 0.01 to 1.5% of lymphocytes within samples from two donors. Experience from this analysis shows that all three programs can be used for the identification of high to intermediate frequency of MHC multimer-binding T cell populations, with results very similar to that of manual gating. For the less frequent populations (<0.1% of live, single lymphocytes), SWIFT outperformed the other tools. As used in this study, none of the algorithms offered a completely automated pipeline for identification of MHC multimer populations, as varying degrees of human interventions were needed to complete the analysis. In this study, we demonstrate the feasibility of using automated analysis pipelines for assessing and identifying even rare populations of antigen-responsive T cells and discuss the main properties, differences, and advantages of the different methods tested

The behaviour of dark matter associated with four bright cluster galaxies in the 10kpc core of Abell 3827

Galaxy cluster Abell 3827 hosts the stellar remnants of four almost equally bright elliptical galaxies within a core of radius 10kpc. Such corrugation of the stellar distribution is very rare, and suggests recent formation by several simultaneous mergers. We map the distribution of associated dark matter, using new Hubble Space Telescope imaging andVery Large Telescope/Multi-Unit Spectroscopic Explorer integral field spectroscopy of a gravitationally lensed system threaded through the cluster core. We find that each of the central galaxies retains a dark matter halo, but that (at least) one of these is spatially offset from its stars. The best-constrained offset is $1.62^{+0.47}_{-0.49}$kpc, where the 68 per cent confidence limit includes both statistical error and systematic biases in mass modelling. Such offsets are not seen in field galaxies, but are predicted during the long infall to a cluster, if dark matter self-interactions generate an extra drag force. With such a small physical separation, it is difficult to definitively rule out astrophysical effects operating exclusively in dense cluster core environments - but if interpreted solely as evidence for self-interacting dark matter, this offset implies a cross-section σDM/m∼(1.7±0.7)×10−4cm2g−1×(tinfall/109 yr)−2, where tinfall is the infall duratio

Deciphering the genome structure and paleohistory of _Theobroma cacao_

We sequenced and assembled the genome of _Theobroma cacao_, an economically important tropical fruit tree crop that is the source of chocolate. The assembly corresponds to 76% of the estimated genome size and contains almost all previously described genes, with 82% of them anchored on the 10 _T. cacao_ chromosomes. Analysis of this sequence information highlighted specific expansion of some gene families during evolution, for example flavonoid-related genes. It also provides a major source of candidate genes for _T. cacao_ disease resistance and quality improvement. Based on the inferred paleohistory of the T. cacao genome, we propose an evolutionary scenario whereby the ten _T. cacao_ chromosomes were shaped from an ancestor through eleven chromosome fusions. The _T. cacao_ genome can be considered as a simple living relic of higher plant evolution