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La Corée dans la collection photographique du peintre Louis-Jules Dumoulin (1860-1924) : l'ombre de Georges-Ferdinand Bigot (1860-1927)
No full textOfficial painter of the Navy and founder of the French artists colonial Society, Louis-Jules Dumoulin has travelled the world and collected a lot of photographs but it seems like he never went to Korea. The main goal of this article is to present his Korean collection and the origin of his photographs.Peintre officiel de la Marine et fondateur de la Société coloniale des artistes français, Louis-Jules Dumoulin a parcouru le monde et collecté de nombreuses photographies, mais il semble bien qu'il ne soit jamais allé en Corée. La présente étude vise à présenter la collection coréenne de Dumoulin et l'origine de ses photographies
Fisher-KPP with time dependent diffusion is able to model cell-sheet activated and inhibited wound closure
No full textInternational audienceThe popular 2D Fisher-KPP equation with constant parameters fails to predict activated or inhibited cell-sheet wound closure. Here, we consider the case where the collective diffusion coefficient is time dependent, with a 3-parameter sigmoid profile. The sigmoid is taken S-shaped for the activated assays, and Z-shaped for the inhibited ones. For two activated and two inhibited assays, our model is able to predict with a very good accuracy features of the wound closure like as the time evolution of the wound area and migration rate. The calibrated parameters are consistent with respect to different subsets of the experimental datasets used for the calibration. However, the assumption of sigmoid time profile for the proliferation rate yields calibrated parameters critically dependent on the dataset used for calibration
The VIMOS Public Extragalactic Redshift Survey (VIPERS). The matter density and baryon fraction from the galaxy power spectrum at redshift
No full textInternational audienceWe use the final catalogue of the VIMOS Public Extragalactic Redshift Survey (VIPERS) to measure the power spectrum of the galaxy distribution at high redshift, presenting results that extend beyond z = 1 for the first time. We apply a fast Fourier transform technique to four independent subvolumes comprising a total of 51 728 galaxies at 0.6 < z < 1.1 (out of the nearly 90 000 included in the whole survey). We concentrate here on the shape of the direction-averaged power spectrum in redshift space, explaining the level of modelling of redshift-space anisotropies and the anisotropic survey window function that are needed to deduce this in a robust fashion. We then use covariance matrices derived from a large ensemble of mock datasets in order to fit the spectral data. The results are well matched by a standard ΛCDM model, with density parameter ΩM h = 0.227+0.063-0.050 and baryon fraction fB=ΩB/ΩM=0.220+0.058-0.072. These inferences from the high-z galaxy distribution are consistent with results from local galaxy surveys, and also with the cosmic microwave background. Thus the ΛCDM model gives a good match to cosmic structure at all redshifts currently accessible to observational study. Key words: cosmological parameters / large-scale structure of Universe / galaxies: high-redshift / galaxies: statistics⋆ Based on observations collected at the European Southern Observatory, Cerro Paranal, Chile, using the Very Large Telescope under programmes 182.A-0886 and partly under programme 070.A-9007. Also based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT), which is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l’Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. This work is based in part on data products produced at TERAPIX and the Canadian Astronomy Data Centre as part of the Canada-France-Hawaii Telescope Legacy Survey, a collaborative project of NRC and CNRS. The VIPERS web site is http://www.vipers.inaf.it
Universal dark halo scaling relation for the dwarf spheroidal satellites
No full textInternational audienceMotivated by a recently found interesting property of the dark halo surface density within a radius, , giving the maximum circular velocity, , we investigate it for dark halos of the Milky Way’s and Andromeda’s dwarf satellites based on cosmological simulations. We select and analyze the simulated subhalos associated with Milky-Way-sized dark halos and find that the values of their surface densities, , are in good agreement with those for the observed dwarf spheroidal satellites even without employing any fitting procedures. Moreover, all subhalos on the small scales of dwarf satellites are expected to obey the universal relation, irrespective of differences in their orbital evolutions, host halo properties, and observed redshifts. Therefore, we find that the universal scaling relation for dark halos on dwarf galaxy mass scales surely exists and provides us with important clues for understanding fundamental properties of dark halos. We also investigate orbital and dynamical evolutions of subhalos to understand the origin of this universal dark halo relation and find that most subhalos evolve generally along the sequence, even though these subhalos have undergone different histories of mass assembly and tidal stripping. This sequence, therefore, should be the key feature for understanding the nature of the universality of
Identification de marques épigénétiques chez le nématode à galles parasite de plantes Meloidogyne incognita
No full textMeloidogyne incognita is the most damaging plant-parasitic nematode in agriculture. M. incognita reproduces in an asexual way by obligatory parthenogenesis. Genetically identical individuals develop from females and form clonal populations. Although these clones share the same genetic heritage, modifications of their phenotype can be observed when they are exposed to unfavorable environments. This phenotypic plasticity is characterized through two phenotypes of interest: sex-differentiation and virulence (i.e. capacity to parasite a resistant crop). Sex-differentiation varies among environmental conditions and was reported to be linked to decondensed chromatin regions. Virulence is an heritable character transmitted in a non-Mendelian way. Our study focuses on identifying the role of epigenome in the generation of phenotypic variability. To this end we detailed the presence of proteins involved in epigenetic regulations in Meloidogyne spp. We also developed a ChIP-seq assay to compare histone modifications between different developmental stages and between virulent and avirulent parasites. Our results allow to detect specific histone patterns associated with M. incognita development. These results lead us to propose a model that could explain sex determination in M. incognita. We also could link virulence acquisition with the loss of some specific genomic regions that contains more than 300 genes including already described potential avirulence factors. This study opens the way for analyzing the role of epigenetic mechanisms at a whole genome scale, and allows to identify novel biological processes involved in phenotypic variation in asexual organisms.Meloidogyne incognita est le nématode causant le plus de dégâts en agriculture. Sa particularité est d'être un organisme à reproduction asexuée obligatoire. Une femelle engendre des clones a priori 100% identiques génétiquement. Pourtant, M. incognita est capable de faire preuve d'une grande plasticité phénotypique lui permettant de répondre à de nouveaux environnements. Un exemple est le déterminisme du sexe, un phénotype lié aux conditions environnementales et semblant impliquer des régulations chromatiniennes. Un autre exemple est la capacité à contourner les résistances des plantes (virulence), un caractère héréditaire mais non-Mendelien. Dans le cadre de cette thèse, j'ai cherché à tester l'implication des mécanismes épigénétiques dans la plasticité phénotypique en absence de sexe de M. incognita. A ces fins, j'ai évalué la conservation des mécanismes épigénétiques chez les nématodes à galles. Cette approche a permis de pointer que les mécanismes connus chez C. elegans sont conservés chez les nématodes parasites de plantes. Puis, une méthodologie de ChIP-seq a été mise en place afin de comparer les profils d'accumulation des marques d'histones chez M. incognita au cours de la réponse aux conditions environnementales. Cette stratégie a permis la mise en évidence 1- de patrons d'histones modifiées marquant le développement du parasite et 2- de régions génomiques comportant plus de 300 gènes dont des candidats facteurs d'avirulence déjà décrits dans la littérature spécifiquement perdue entre M. incognita (a)virulents. Ces travaux de thèse présentent un intérêt fondamental sur la compréhension de l'évolution d'un organisme en absence de reproduction sexuée
De Lesbos à Calais : comment l’Europe fabrique des camps. Introduction
No full textInternational audienceDe Lesbos à Calais, une myriade de lieux de mise à l’écart émaille les parcours des migrants. Ces camps se forment partout où la circulation des migrants est empêchée, aux portes d’entrées vers l’Europe comme aux frontières nationales. Ils apparaissent aussi dans les lieux de mise en attente des migrants : attente de la reconnaissance d’un statut administratif stable, d’un logement, d’une prise en charge. Enfin, les camps ont de longue date été les lieux où s’articulent les logiques d’enfermement, de contrôle et de tri des migrants. Logiques toujours à l’œuvre au sein des hotspots, réponse de l’Union Européenne à la « crise des migrants ».Ces camps sont différents dans leurs morphologies (camps ouverts, camps fermés), par leurs fonctionnements (autogestion des migrants, gestion humanitaire, enfermement sur le modèle carcéral, etc.), de par les acteurs qui les investissent. Penser ensemble ces bidonvilles des bordures urbaines, les campements en villes, les centres de rétention et hotspots, fait néanmoins apparaitre le continuum auquel ils participent, celui d’une mise à l’écart des migrants, d’un traitement par le temporaire. Cet encampement transforme les frontières en des espaces de mise en attente où s’organise la vie des migrants. Ces espaces de relégation sont aussi des lieux d’où émergent des prises de conscience collective, des modes d’agir et de revendications politiques de la part des migrants. Ils sont également les lieux où se cristallisent des formes de solidarités citoyennes et riveraines qui débordent la seule hospitalité publique instaurée institutionnellement. Par leurs seules présences ces camps transforment les espaces urbains, des murs s’érigent pour barrer le passage, des barrières se dressent pour empêcher des installations de migrants. En cela, le retour des camps en Europe, censé répondre à la « crise des migrants », révèle la réalité d’une crise politique et d’une crise de l’hospitalité qui fait du provisoire et de la mise à l’écart les seules manières de penser la gestion des migrations contemporaines
Image coding using Leaky Integrate-and-Fire neurons
No full textInternational audienceThis paper aims to build an image coding system based on the model of the mammalian retina. The retina is the light-sensitive layer of tissue located on the inner coat of the eye and it is responsible for vision. Inspired by the way the retina handles and compresses the visual information and based on previous studies we aim to build and analytically study a retinal-inspired image quantizer, based on the Leaky Integrate-and-Fire (LIF) model, a neural model according to which function the ganglion cells of the Ganglionic retinal layer that is responsible for the visual data compression. In order to have a more concrete view of the encoder's behavior, in our experiments, we make use of the spatiotemporal decomposition layers provided by extensive previous studies on a previous retinal layer, the Outer Plexiform Layer (OPL). The decomposition layers produced by the OPL, are being encoded using our LIF image encoder and then, they are reconstructed to observe the en-coder's efficiency
Effects of Combined Vigorous Interval Training Program and Diet on Body Composition, Physical Fitness, and Physical Self-Perceptions Among Obese Adolescent Boys and Girls
No full textInternational audiencePurpose: This study examined the effects of a five-week intervention combining vigorous interval training (VIT) with diet among twenty-four obese adolescents. Fourteen girls and ten boys (aged 14–15) schooled in a pediatric rehabilitation center participated.Methods: The VIT intensity was targeted and remained above 80% of maximal heart rate (HR) and over six kilocalories per minute. Pre-and postintervention measures were body composition (BMI, weight, body fat percentage), physical self-perceptions (PSP), physical fitness (6-min walking distance and work) and its associated physiological responses (HR peak and blood lactate concentration). A series of two-way analyses of variance or covariance controlling for weight loss were used to examine the changes.Results: Significant improvements were found in body composition, physical fitness and PSP (endurance, activity level, sport competence, global physical self-concept and appearance). In addition, boys presented higher levels of perceived strength and global physical self-concept than girls. Finally, there was a significant increase in perceived endurance, sport competence, and global physical self-concept in girls only.Conclusion: This five-week VIT program combined with diet represents an effective means for improving body composition, physical fitness, and PSP in obese adolescents, the effects on PSP being larger among girls
Verbal classes in Somali: Allomorphy has no classificatory function
No full textInternational audienc
A non-coding function of TYRP1 mRNA promotes melanoma growth
No full textInternational audienceCompetition among RNAs to bind miRNA is proposed to influence biological systems. However, the role of this competition in disease onset is unclear. Here, we report that TYRP1 mRNA, in addition to encoding tyrosinase-related protein 1 (TYRP1), indirectly promotes cell proliferation by sequestering miR-16 on non-canonical miRNA response elements. Consequently, the sequestered miR-16 is no longer able to repress its mRNA targets, such as RAB17, which is involved in melanoma cell proliferation and tumour growth. Restoration of miR-16 tumour-suppressor function can be achieved in vitro by silencing TYRP1 or increasing miR-16 expression. Importantly, TYRP1-dependent miR-16 sequestration can also be overcome in vivo by using small oligonucleotides that mask miR-16-binding sites on TYRP1 mRNA. Together, our findings assign a pathogenic non-coding function to TYRP1 mRNA and highlight miRNA displacement as a promising targeted therapeutic approach for melanoma