THE USE OF GLOBAL SENSITIVITY ANALYSIS FOR ASSESSING CAPABILITY OF THE MTG/FCI INSTRUMENT TO DETECT AEROSOLS

International audienceThe Flexible Combined Imager (FCI) is an instrument to be borne by the future geostationary meteorological satellite Meteosat Third Generation (MTG). A numerical simulator was set up to provide simulated outputs of the instrument. It includes top-of-atmosphere scene of upwelling spectral radiance obtained by a radiative transfer model in the clear atmosphere, and the transfer function of the FCI. The sensitivity of the sensor outputs to aerosol properties is studied by varying the inputs defining the scenes and their illumination. The Global Sensitivity Analysis (GSA) with the Sobol' decomposition is applied to the outputs of the simulator, yielding a ranking of the inputs with respect to their influence on the FCI numerical outputs. The results are presented for all visible and near infrared channels of the FCI for desert type of aerosols according to the OPAC database. The study highlights the most relevant channels for aerosol detection and characterization and gives assessment of the different sources of uncertainties in aerosol retrieval with such channels

海洋性プランクトン群の進化と生態についての研究

平成30年度 京都大学化学研究所 スーパーコンピュータシステム 利用報告

Existence of the thermodynamic limit for disordered quantum Coulomb systems

Following a recent method introduced by C. Hainzl, J.P. Solovej and the second author of this article, we prove the existence of the thermodynamic limit for a system made of quantum electrons, and classical nuclei whose positions and charges are randomly perturbed in an ergodic fashion. All the particles interact through Coulomb forces.Comment: To appear in J. Math. Phys. (special issue in honor of E.H. Lieb

An improved genome of the model marine alga Ostreococcus tauri unfolds by assessing Illumina de novo assemblies

Background: Cost effective next generation sequencing technologies now enable the production of genomic datasets for many novel planktonic eukaryotes, representing an understudied reservoir of genetic diversity. O. tauri is the smallest free-living photosynthetic eukaryote known to date, a coccoid green alga that was first isolated in 1995 in a lagoon by the Mediterranean sea. Its simple features, ease of culture and the sequencing of its 13 Mb haploid nuclear genome have promoted this microalga as a new model organism for cell biology. Here, we investigated the quality of genome assemblies of Illumina GAIIx 75 bp paired-end reads from Ostreococcus tauri, thereby also improving the existing assembly and showing the genome to be stably maintained in culture. Results: The 3 assemblers used, ABySS, CLCBio and Velvet, produced 95% complete genomes in 1402 to 2080 scaffolds with a very low rate of misassembly. Reciprocally, these assemblies improved the original genome assembly by filling in 930 gaps. Combined with additional analysis of raw reads and PCR sequencing effort, 1194 gaps have been solved in total adding up to 460 kb of sequence. Mapping of RNAseq Illumina data on this updated genome led to a twofold reduction in the proportion of multi-exon protein coding genes, representing 19% of the total 7699 protein coding genes. The comparison of the DNA extracted in 2001 and 2009 revealed the fixation of 8 single nucleotide substitutions and 2 deletions during the approximately 6000 generations in the lab. The deletions either knocked out or truncated two predicted transmembrane proteins, including a glutamate-receptor like gene. Conclusion: High coverage (>80 fold) paired-end Illumina sequencing enables a high quality 95% complete genome assembly of a compact ~13 Mb haploid eukaryote. This genome sequence has remained stable for 6000 generations of lab culture

Rapid onset of collectivity in the vicinity of 78Ni

gamma-rays following the B and B-n decay of the very neutron rich 84Ga produced by photo-fission of 238U have been studied at the newly built ISOL facility of IPN Orsay: ALTO. Two activities were observed and assigned to two B-decaying states: 84gGa, I = (0\^-) and 84mGa, I = (3\^-, 4\^-). Excitation energies of the 2+1 and 4+1 excited states of 84Ge were measured at E(2+1) = 624.3 keV and E(4+1) = 1670.1 keV. Comparison with HFB+GCM calculations allows to establish the collective character of this nucleus indicating a substantial N=50 core polarization. The excitation energy of the 1/2+1 state in 83Ga known to carry a large part of the neutron 3s1/2 strength was measured at 247.8keV. Altogether these data allow to confirm the new single particle state ordering which appears immediately after the double Z=28 and N=50 shell closure and to designate 78Ni as a fragile and easily polarized doubly-magic core.Comment: 4 pages, ReVTe

Organellar inheritance in the green lineage: insights from Ostreococcus tauri

Along the green lineage (Chlorophyta and Streptophyta), mitochondria and chloroplast are mainly uniparentally transmitted and their evolution is thus clonal. The mode of organellar inheritance in their ancestor is less certain. The inability to make clear phylogenetic inference is partly due to a lack of information for deep branching organisms in this lineage. Here, we investigate organellar evolution in the early branching green alga Ostreococcus tauri using population genomics data from the complete mitochondrial and chloroplast genomes. The haplotype structure is consistent with clonal evolution in mitochondria, while we find evidence for recombination in the chloroplast genome. The number of recombination events in the genealogy of the chloroplast suggests that recombination, and thus biparental inheritance, is not rare. Consistent with the evidence of recombination, we find that the ratio of the number of nonsynonymous to the synonymous polymorphisms per site is lower in chloroplast than in the mitochondria genome. We also find evidence for the segregation of two selfish genetic elements in the chloroplast. These results shed light on the role of recombination and the evolutionary history of organellar inheritance in the green lineage

Sterol biosynthesis pathway is part of the interferon host defence response

Recently, cholesterol metabolism has been shown to modulate the infection of several viruses and there is growing evidence that inflammatory response to infection also modulates lipid metabolism. However little is known about the role of inflammatory processes in modulating lipid metabolism and their consequences for the viral infection. This study investigates host-lipid viral interaction pathways using mouse cytomegalovirus, a large double-stranded DNA genome, which represents one of the few models for a natural infection of its natural host. In this study, transcriptomic and lipidomic profiling of macrophages shows that there is a specific coordinated regulation of the sterol pathways upon viral infection or treatment with IFNγ or β (but not TNFα, IL1β or IL6) resulting in the decrease of free cellular cholesterol. Furthermore, we show that pharmacological and RNAi inhibition of the sterol pathway augments protection against infection in vitro and in vivo and we identified that the prenylation branch of the sterol metabolic network was involved in the protective response. Finally, we show that genetic knock out of IFNβ results in a partial reduction while genetic knock out of Ifnar1 completely abolishes the reduction of the sterol biosynthetic activity upon infection. Overall these results support a role for part of the sterol metabolic network in protective immunity and show that type 1 IFN signalling is both necessary and sufficient for reducing the sterol metabolic network upon infection; thereby linking the sterol pathway with IFN defence responses

Asp Viper (Vipera aspis) Envenomation: Experience of the Marseille Poison Centre from 1996 to 2008

A retrospective case review study of viper envenomations collected by the Marseille’s Poison Centre between 1996 and 2008 was performed. Results: 174 cases were studied (52 grade 1 = G1, 90 G2 and 32 G3). G1 patients received symptomatic treatments (average hospital stay 0.96 day). One hundred and six (106) of the G2/G3 patients were treated with the antivenom Viperfav* (2.1+/-0.9 days in hospital), while 15 of them received symptomatic treatments only (plus one immediate death) (8.1+/-4 days in hospital, 2 of them died). The hospital stay was significantly reduced in the antivenom treated group (p < 0.001), and none of the 106 antivenom treated patients had immediate (anaphylaxis) or delayed (serum sickness) allergic reactions. Conclusion: Viperfav* antivenom was safe and effective for treating asp viper venom-induced toxicity