New one-pot synthesis of Au and Ag nanoparticles using green rust reactive particle as a micro-reactor

A new, simple, and fast one-pot synthesis of supported Au or Ag nanoparticles is implemented, for which a reactive Fe(II)-bearing green rust inorganic particle is used as an individual micro-reactor acting as both the reducing agent and support for the resulting metal nanoparticles. The mechanism involves both the solid-state oxidation of the green rust support (sulfate or carbonate) and the reduction-precipitation of soluble metal precursor. The resulting nanohybrids have a platy inorganic part supporting about one to ten nanoparticles with sizes in the 20 to 120 nm range

Whole Genome DNA Methylation (Methylome) Analysis of an Entomopathogenic Bacterium

Background: DNA methylation is an epigenetic mechanism involved in the pathogenicity of several major bacterial pathogens. It can decrease the affinity of some transcriptional regulators to their binding site, leading to sub-populations expressing or not various genes, depending on the DNA methylation state. Dam DNA methyltransferase is widespread in Gammaproteobacteria and methylates the adenine of GATC sites. Objectives: The role of Dam was investigated in Photorhabdus luminescens during its symbiosis with a soil nematode and during its pathogenic stage in insects.Methods: SMRT sequencing (PacBio) and Bisulfite-seq were performed to identify the DNA methylation of the whole genome (methylome). In addition, RNAseq and phenotypic analysis were performed in a P. luminescens strain overexpressing Dam.Results: Dam overexpression caused a decrease in motility whereas it increased biofilm formation. While symbiosis ability of the Dam overexpressing strain was not significantly different from that of a control strain, the nemato-bacterial complex displayed an impaired pathogenicity in insect, as also observed after direct insect injection of the bacteria alone. Transcriptomic analysis revealed that the observed phenotypes were related to differences at the transcriptional level. More than 99% of the GATC sites of the genome were found methylated and DNA methylation levels did not change over growth kinetics. However, the Dam-overexpressing strain displayed more methylated GATC sites than the control and most of these sites were located in promoter regions. These sites may be involved in the observed differences in phenotypes and gene expression and provide clues to understand the involvement of Dam DNA methylation in P. luminescens life-cycle

Building an Observatory of Course-of-Action in Software Engineering: towards a Link between ISO/IEC Software Engineering standards and a Reflective Practice

International audienceAs a help to compete in an evolving market, small software companies may use an observatory of their course-of-action. The course of action considers the observable aspect of the actor's activity. Its analysis provides a description of actors' activity and it can express recommendations concerning both the individual situations and the collective situation. The observatory is an articulated set of data collecting methods supported with semantic wikis and a dedicated application. A case study, based on the activity of a team of 6 young software engineers, depicts some aspects of the building and the filling of the course-of-action observatory. As primary results of this work, we may think that observing and analyzing software engineer's activity help to reveal his/her theory-in-use - what governs engineers' behavior and tends to be tacit structures - That may help engineers to establish links between "Project Processes-in-use" and a simplified Process Reference Model and contribute to reduce the fit between a project-in-action and espoused SE standards

Genetic control of plasticity of oil yield for combined abiotic stresses using a joint approach of crop modeling and genome-wide association

Understanding the genetic basis of phenotypic plasticity is crucial for predicting and managing climate change effects on wild plants and crops. Here, we combined crop modeling and quantitative genetics to study the genetic control of oil yield plasticity for multiple abiotic stresses in sunflower. First we developed stress indicators to characterize 14 environments for three abiotic stresses (cold, drought and nitrogen) using the SUNFLO crop model and phenotypic variations of three commercial varieties. The computed plant stress indicators better explain yield variation than descriptors at the climatic or crop levels. In those environments, we observed oil yield of 317 sunflower hybrids and regressed it with three selected stress indicators. The slopes of cold stress norm reaction were used as plasticity phenotypes in the following genome-wide association study. Among the 65,534 tested SNP, we identified nine QTL controlling oil yield plasticity to cold stress. Associated SNP are localized in genes previously shown to be involved in cold stress responses: oligopeptide transporters, LTP, cystatin, alternative oxidase, or root development. This novel approach opens new perspectives to identify genomic regions involved in genotype-by-environment interaction of a complex traits to multiple stresses in realistic natural or agronomical conditions.Comment: 12 pages, 5 figures, Plant, Cell and Environmen

Distribution and characteristics of urban nesting sites of sympatric swifts

Distribution and nest locations of Common and Pallid Swifts are compared in two towns located in the Mediterranean zone, Bastia in Corsica and Nice on the French Riviera. Our goal is to evaluate whether nesting site selection by swifts on urban settings differs between the two locations. First, we noted an avoidance in the distribution between the two swifts in both towns. Secondly, our results show that Common and Pallid Swifts use different nesting sites to breed in Bastia, whereas the same structures are used by the two species in Nice. Requirement of each species differs between the two localities, suggesting that nesting site use is more locality dependent than species dependent

Identification of novel genes potentially involved in somatic embryogenesis in chicory (Cichorium intybus L.)

<p>Abstract</p> <p>Background</p> <p>In our laboratory we use cultured chicory (<it>Cichorium intybus</it>) explants as a model to investigate cell reactivation and somatic embryogenesis and have produced 2 chicory genotypes (K59, C15) sharing a similar genetic background. K59 is a responsive genotype (embryogenic) capable of undergoing complete cell reactivation <it>i.e</it>. cell de- and re-differentiation leading to somatic embryogenesis (SE), whereas C15 is a non-responsive genotype (non-embryogenic) and is unable to undergo SE. Previous studies <abbrgrp><abbr bid="B1">1</abbr></abbrgrp> showed that the use of the β-D-glucosyl Yariv reagent (β-GlcY) that specifically binds arabinogalactan-proteins (AGPs) blocked somatic embryo production in chicory root explants. This observation indicates that β-GlcY is a useful tool for investigating somatic embryogenesis (SE) in chicory. In addition, a putative AGP (DT212818) encoding gene was previously found to be significantly up-regulated in the embryogenic K59 chicory genotype as compared to the non-embryogenic C15 genotype suggesting that this AGP could be involved in chicory re-differentiation <abbrgrp><abbr bid="B2">2</abbr></abbrgrp>. In order to improve our understanding of the molecular and cellular regulation underlying SE in chicory, we undertook a detailed cytological study of cell reactivation events in K59 and C15 genotypes, and used microarray profiling to compare gene expression in these 2 genotypes. In addition we also used β-GlcY to block SE in order to identify genes potentially involved in this process.</p> <p>Results</p> <p>Microscopy confirmed that only the K59, but not the C15 genotype underwent complete cell reactivation leading to SE formation. β-GlcY-treatment of explants blocked <it>in vitro </it>SE induction, but not cell reactivation, and induced cell wall modifications. Microarray analyses revealed that 78 genes were differentially expressed between induced K59 and C15 genotypes. The expression profiles of 19 genes were modified by β-GlcY-treatment. Eight genes were both differentially expressed between K59 and C15 genotypes during SE induction and transcriptionally affected by β-GlcY-treatment: <it>AGP </it>(DT212818), <it>26 S proteasome AAA ATPase subunit 6 </it>(<it>RPT6</it>), <it>remorin </it>(<it>REM</it>), <it>metallothionein-1 </it>(<it>MT1</it>), two non-specific lipid transfer proteins genes (<it>SDI-9 and DEA1</it>), <it>3-hydroxy-3-methylglutaryl-CoA reductase </it>(<it>HMG-CoA reductase</it>), and <it>snakin 2 </it>(<it>SN2</it>). These results suggest that the 8 genes, including the previously-identified <it>AGP </it>gene (DT212818), could be involved in cell fate determination events leading to SE commitment in chicory.</p> <p>Conclusion</p> <p>The use of two different chicory genotypes differing in their responsiveness to SE induction, together with β-GlcY-treatment represented an efficient tool to discriminate cell reactivation from the SE morphogenetic pathway. Such an approach, together with microarray analyses, permitted us to identify several putative key genes related to the SE morphogenetic pathway in chicory.</p

A role for lipid rafts in the protection afforded by docosahexaenoic acid against ethanol toxicity in primary rat hepatocytes.

International audience: Previously, we demonstrated that eicosapentaenoic acid enhanced ethanol-induced oxidative stress and cell death in primary rat hepatocytes via an increase in membrane fluidity and lipid raft clustering. In this context, another n-3 polyunsaturated fatty acid, docosahexaenoic acid (DHA), was tested with a special emphasis on physical and chemical alteration of lipid rafts. Pretreatment of hepatocytes with DHA reduced significantly ethanol-induced oxidative stress and cell death. DHA protection could be related to an alteration of lipid rafts. Indeed, rafts exhibited a marked increase in membrane fluidity and packing defects leading to the exclusion of a raft protein marker, flotillin. Furthermore, DHA strongly inhibited disulfide bridge formation, even in control cells, thus suggesting a disruption of protein-protein interactions inside lipid rafts. This particular spatial organization of lipid rafts due to DHA subsequently prevented the ethanol-induced lipid raft clustering. Such a prevention was then responsible for the inhibition of phospholipase C-γ translocation into rafts, and consequently of both lysosome accumulation and elevation in cellular low-molecular-weight iron content, a prooxidant factor. In total, the present study suggests that DHA supplementation could represent a new preventive approach for patients with alcoholic liver disease based upon modulation of the membrane structures

Limits to the principle of State consent to the jurisdiction of the World Court : (Law and legal policy)

Le principe du consentement des Etats à la compétence de la Cour internationale de Justice (CIJ) et de sa devancière, la Cour permanente de Justice internationale (CPJI), est un principe fondamental du procès international. Selon la Cour, appuyée par la doctrine, la compétence de la Cour serait même entièrement gouvernée par ce principe. Affirmer l’existence de limites induit un hiatus entre la théorie et la pratique. L’étude des sources de la compétence de la Cour conduit en effet à identifier des éléments qui ne s’accordent pas avec ce discours. La réalité des affaires devant la Cour contraste avec l’image renvoyée d’une juridiction sous la tutelle du consentement des Etats à sa compétence, et met en lumière les politiques juridiques poursuivies par les principaux acteurs du procès devant la Cour : les Etats et la Cour elle-même.The principle of State consent to the jurisdiction of the International Court of Justice (ICJ) and that of its predecessor, the Permanent Court of International Justice (PCIJ), is a fundamental principle of international adjudication. According to the Court, and academic commentary, the Court's jurisdiction is governed entirely by this principle. However, affirming the existence of limits reveals a gap between theory and practice. Study of the sources of the Court's jurisdiction leads to the identification of factors which do not support this discourse. The reality of cases before the Court contrasts with the perception of a court rigidly subject to State consent to its jurisdiction, and brings to light the legal policies pursued by the principal actors in proceedings before the Court: States and the Court itself

Pertinence d'une information systématique sur les directives anticipées auprès des patients d'une consultation mémoire

CONTEXTE La Haute Autorité de Santé recommande d’informer les patients se présentant en consultation mémoire sur la possibilité de rédiger ses directives anticipées, ce qui est peu fait en pratique.OBJECTIF Cette étude propose d’analyser la pertinence d’une information organisée au sein d’une consultation mémoire visant à améliorer l’appropriation des directives anticipées chez les patients âgés et d’étudier en particulier l’impact de cette information auprès des patients avec un diagnostic d’un probable trouble neurocognitif.MÉTHODES Nous avons réalisé une étude de cohorte prospective interventionnelle de type avant-après à l’aide d’une information pré consultation et de rappels à distance.RÉSULTATS 61 patients ont été inclus dans l’étude, 15% d’entre eux ne connaissaient pas les directives anticipées avant l’étude et 32,2% ne se sentaient pas concernés. Après étude, 45% des patients qui ont pu être joints et 75% de leurs accompagnants se souvenaient de l’information. Le fait de se souvenir est corrélé de manière significative à un haut MMS (Mini Mental State test, p=0,0068). Un haut MMS est également corrélé à l’intention de rédiger ses directives anticipées (p=0,0203).CONCLUSION Cette étude montre que l’information systématique des patients se présentant en consultation mémoire n’est pas pertinente et qu’elle doit être réservée aux patients ne présentant pas de troubles cognitifs ou des troubles très légers, ce qui est finalement en accord avec l’approche des médecins consultants au centre mémoire

Synthesis and characterization of noble metal nanoparticles-oxidized carbonate green rust nanohybrids

International audienceIn this study, we report new metal-inorganic nanohybrids constituted of Au, Ag or Pt nanoparticles supported on oxidized carbonate green rust particles. These nanohybrids are obtained from two successive steps in "one pot", synthesis of a carbonate green rust suspension followed by its redox reaction with noble-metal soluble precursor. In this process, carbonate green rust, a health- and environment-friendly compound, is used as both the reducing agent and the support for metal nanoparticles. The obtained nanohybrids are characterized by FTIR, XRD and SEM. They display an inorganic part that keeps the platy shape characteristic of green rust and about 1-10 metal nanoparticles of several tens of nanometers in diameter are present on both faces. By annealing at 250 °C, metal-haematite nanohybrids keeping similar morphology were obtained