Peut-on former les enseignant·e·s en un rien de temps ?

National audienceIn France, we recently realized that it is urgent to stop waiting to start teaching our girls and boys bases of computer science, to master digital technology, and the Digital Science and Technology (SNT) topic is now offered in Year 11 (classe de 2nd), starting at the 2019 school year. All highschool students are concerned. But how to train teachers? It is a challenge and it should be done in almost no time. By using quantitative data about the Class'Code training program and putting the methodological elements developed and experimented in perspective, we report here what did work and, more interesting, where we stumbled in order to set the limits of the approach and show the importance of a greater place regarding these formations.En France, on a récemment compris qu'il est urgent de ne plus attendre pour initier nos filles et nos garçons à l'informatique pour maîtriser le numérique : l'enseignement de Sciences Numériques et Technologie (SNT) va, en classe de seconde à la rentrée 2019, concerner tou·te·s les lycéen·ne·s. Mais comment former les enseignant·e·s ? C'est un défi qu'il faudrait relever en peu de temps. En utilisant des données quantitatives sur les formations Class´Code et en prenant du recul sur les éléments méthodologiques développés et expérimentés, nous faisons ici un retour d'expérience sur ce qui a pu marcher et, plus intéressant encore, là où nous avons buté afin de poser les limites de l'approche et montrer la nécessité d'une place plus grande pour ce type de formations

Interacting fermions in self-similar potentials

We consider interacting spinless fermions in one dimension embedded in self-similar quasiperiodic potentials. We examine generalizations of the Fibonacci potential known as precious mean potentials. Using a bosonization technique and a renormalization group analysis, we study the low-energy physics of the system. We show that it undergoes a metal-insulator transition for any filling factor, with a critical interaction that strongly depends on the position of the Fermi level in the Fourier spectrum of the potential. For some positions of the Fermi level the metal-insulator transition occurs at the non interacting point. The repulsive side is an insulator with a gapped spectrum whereas in the attractive side the spectrum is gapless and the properties of the system are described by a Luttinger liquid. We compute the transport properties and give the characteristic exponents associated to the frequency and temperature dependence of the conductivity.Comment: 18 pages, 10 EPS figure

VARIATIONS DEPUIS 10000 ANS DE LA REPARTITION ET DE LA PRODUCTIVITE DES FORETS D'ALTITUDE DANS LES ALPES ET LE JURA ET SIMULATION DES CHANGEMENTS FUTURS

Ce travail repose sur les charbons de bois enfouis dans les sols et les autres macrorestes ont été datés par 14C et identifiés botaniquement, et pour un site particulier (lac Cristol), sur les analyses de pollens, d'insectes, de macro-restes végétaux, charbons de bois et tronc d'arbres ont été combinés en une « approche multi-proxy » afin de mieux comprendre les variations de la forêt de montagne en réponse aux changements climatiques globaux et à l'activité anthropique. Les variations de la limite de la forêt sont de plus de 500 m durant l'Holocène. La période la plus chaude semble avoir été 9000-8000 ans cal B.P. (années calendaires avant le présent). Les hauts niveaux lacustres du début et de la fin de l'Holocène sont de natures en fait assez différentes. Au début de l'Holocène ils sont principalement dus à une évapotranspiration plus faible, et à la fin de l'Holocène à des précipitations plus élevées. L'ensemble de ces informations a permis de tester un modèle de végétation (Biome3) par une utilisation en mode inverse et à essayer de prédire l'évolution de la végétation. Un doublement de CO2 permet à la végétation d'évoluer vers des conditions plus tempérées. Une « forêt mixte tempérée », pourra devenir une forêt décidue tempérée grâce à des hivers nettement plus doux et à une meilleure efficacité dans l'utilisation de l'eau en été. Ces sites d'altitude ont connu une telle végétation entre 9000 et 8000 ans cal B.P

Plant-mediated effects on mosquito capacity to transmit human malaria

The ecological context in which mosquitoes and malaria parasites interact has received little attention, compared to the genetic and molecular aspects of malaria transmission. Plant nectar and fruits are important for the nutritional ecology of malaria vectors, but how the natural diversity of plant-derived sugar sources affects mosquito competence for malaria parasites is unclear. To test this, we infected Anopheles coluzzi, an important African malaria vector, with sympatric field isolates of Plasmodium falciparum, using direct membrane feeding assays. Through a series of experiments, we then examined the effects of sugar meals from Thevetia neriifolia and Barleria lupilina cuttings that included flowers, and fruit from Lannea microcarpa and Mangifera indica on parasite and mosquito traits that are key for determining the intensity of malaria transmission. We found that the source of plant sugar meal differentially affected infection prevalence and intensity, the development duration of the parasites, as well as the survival and fecundity of the vector. These effects are likely the result of complex interactions between toxic secondary metabolites and the nutritional quality of the plant sugar source, as well as of host resource availability and parasite growth. Using an epidemiological model, we show that plant sugar source can be a significant driver of malaria transmission dynamics, with some plant species exhibiting either transmission-reducing or -enhancing activities

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

The clinical effectiveness and cost-effectiveness of abatacept, adalimumab, etanercept and tocilizumab for treating juvenile idiopathic arthritis: a systematic review and economic evaluation

Background: Juvenile idiopathic arthritis (JIA) is characterised by joint pain, swelling and limitation of movement caused by inflammation. Subsequent joint damage can lead to disability and growth restriction. Treatment commonly includes disease modifying anti-rheumatic drugs (DMARD) such as methotrexate. Clinical practice now favours newer drugs termed biologic DMARDs where indicated.Objective: To assess the clinical and cost-effectiveness of four biologic DMARDs (etanercept, abatacept, adalimumab and tocilizumab - with or without methotrexate where indicated) for the treatment of JIA (systemic or oligoarticular JIA excluded).Data sources: Electronic bibliographic databases including MEDLINE, EMBASE, The Cochrane Library and DARE were searched for published studies from inception to May 2015 for English language articles. Bibliographies of related papers, systematic reviews and company submissions were screened and experts were contacted to identify additional evidence.Review methods: Systematic reviews of clinical-effectiveness, health-related quality of life and cost-effectiveness were undertaken according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. A cost-utility decision analytic model was developed to compare estimated cost-effectiveness of biologic DMARDs versus methotrexate. The base case time horizon was 30 years and the model took a National Health Service (NHS) perspective, with costs and benefits discounted at 3.5%.Results: Four placebo-controlled RCTs met the inclusion criteria for the clinical-effectiveness review (one RCT evaluating each biologic DMARD). Only one RCT included UK participants. Participants had to achieve an American College of Rheumatology Pediatric (ACR Pedi) 30 response to open-label lead-in treatment in order to be randomised. An exploratory adjusted indirect comparison suggests that the four biologic DMARDs are similar with fewer disease flares and greater proportions with ACR Pedi 50 and 70 responses among participants randomised to continued biologic DMARD. However, confidence intervals were wide, the number of trials was low and there was clinical heterogeneity between trials. Open-label extensions of the trials showed that generally ACR responses remained constant or even increased after the double-blind phase. The proportions of adverse events and serious adverse events were generally similar between treatment and placebo groups. Four economic evaluations of biologic DMARDs for patients with JIA were identified but all had limitations. Two quality of life studies were included, one of which informed the cost-utility model. The incremental cost-effectiveness ratio (ICER) for adalimumab, etanercept and tocilizumab versus methotrexate was £38,127, £32,526 and £38,656 per QALY, respectively. The ICER for abatacept versus methotrexate as a second line biologic was £39,536 per QALY.Limitations: The model does not incorporate the natural history of JIA in terms of long-term disease progression, as the current evidence is limited. There are no head-to-head trials of biologic DMARDs and clinical evidence for specific JIA subtypes is limited.Conclusions: Biologic DMARDs are superior to placebo (with methotrexate where permitted) in children with (predominantly) polyarticular course JIA, and an insufficient response to previous treatment. Randomised comparisons of biologic DMARDs with long-term efficacy and safety follow- are needed to establish comparative effectiveness. RCTs for JIA subtypes where evidence is lacking are also required.Funding: The National Institute for Health Research Health Technology Assessment programme. <br/

Methylobacterium Genome Sequences: A Reference Blueprint to Investigate Microbial Metabolism of C1 Compounds from Natural and Industrial Sources

Methylotrophy describes the ability of organisms to grow on reduced organic compounds without carbon-carbon bonds. The genomes of two pink-pigmented facultative methylotrophic bacteria of the Alpha-proteobacterial genus Methylobacterium, the reference species Methylobacterium extorquens strain AM1 and the dichloromethane-degrading strain DM4, were compared. Methodology/Principal Findings The 6.88 Mb genome of strain AM1 comprises a 5.51 Mb chromosome, a 1.26 Mb megaplasmid and three plasmids, while the 6.12 Mb genome of strain DM4 features a 5.94 Mb chromosome and two plasmids. The chromosomes are highly syntenic and share a large majority of genes, while plasmids are mostly strain-specific, with the exception of a 130 kb region of the strain AM1 megaplasmid which is syntenic to a chromosomal region of strain DM4. Both genomes contain large sets of insertion elements, many of them strain-specific, suggesting an important potential for genomic plasticity. Most of the genomic determinants associated with methylotrophy are nearly identical, with two exceptions that illustrate the metabolic and genomic versatility of Methylobacterium. A 126 kb dichloromethane utilization (dcm) gene cluster is essential for the ability of strain DM4 to use DCM as the sole carbon and energy source for growth and is unique to strain DM4. The methylamine utilization (mau) gene cluster is only found in strain AM1, indicating that strain DM4 employs an alternative system for growth with methylamine. The dcm and mau clusters represent two of the chromosomal genomic islands (AM1: 28; DM4: 17) that were defined. The mau cluster is flanked by mobile elements, but the dcm cluster disrupts a gene annotated as chelatase and for which we propose the name “island integration determinant” (iid).Conclusion/Significance These two genome sequences provide a platform for intra- and interspecies genomic comparisons in the genus Methylobacterium, and for investigations of the adaptive mechanisms which allow bacterial lineages to acquire methylotrophic lifestyles.Organismic and Evolutionary Biolog