Vegetative propagation studies of gum arabic trees : 2. The vegetative propagation of adult Acacia senegal

Le bouturage d'Acacia senegal est possible à partir de fragments de rameaux prélevés dans le houppier d'arbres adultes (13 ans). Le matériel végétal le plus réactif est constitué par des boutures de 15 cm de long (12 à 15 nouds) et de 10 +/- 6 mm de diamètre. L'ablation des feuilles avant mise en culture est un facteur favorable à l'enracinement des boutures. Celui-ci est aussi très influencé par la date de prélèvement des boutures et il varie de 10% en saison sèche à plus de 70% en saison des pluies. La collecte de boutures peut se faire sous forme de fragments de rameaux de 50 cm de long. Il est alors possible de conserver ce matériel pendant huit jours dans une toile maintenue humide et d'y découper les boutures au moment de la mise en place en pépinière. Les boutures présentent des caractères de maturité (croissance lente, plagiotropie, fructification). Il est cependant possible de conserver les génotypes ainsi mobilisés au champ, ou dans des pots en pépinière, afin d'amplifier le processus de rajeunissement physiologique en vue de leur clonage in vitr

Socioeconomic status and site-specific cancer incidence, a Bayesian approach in a French Cancer Registries Network study

International audienceThe aim of this study was to identify and compare cancer sites whose incidence is influenced by social deprivation. The study population comprised 189 144 cases of cancer diagnosed between 2006 and 2009, recorded in member registries of the French Network of Cancer Registries. Social environment was assessed at an aggregate level using the European Deprivation Index. The association between incidence and socioeconomic status was assessed by a geographical Bayesian Poisson model enabling a reduction of the overall variability and smoothing of the relative risks by sharing information provided by multiple geographic units. For cancers of the stomach, liver, lips-mouth-pharynx, and lung, a higher incidence in deprived populations was found for both sexes as well as for cancers of the larynx, esophagus, pancreas, and bladder in men and cervical cancer in women. For melanoma, prostate, testis, ovarian, and breast cancer, a higher incidence was observed in affluent populations. The highest relative risks of the lowest social class compared with the highest social class were found for larynx [relative risk (RR) = 1.67 (1.43-1.95)], lips-mouth-pharynx [RR = 1.89 (1.72-2.07)], and lung cancer [RR = 1.59 (1.50-1.68)] in men and for cervix [RR = 1.62 (1.40-1.88)] and lips-mouth-pharynx [RR = 1.56 (1.30-1.86)] cancer in women. By estimating the burden of social deprivation on cancer incidence throughout France, this study enables us to measure the gains that could be achieved by implementing targeted prevention efforts

Équipement médical des refuges de montagne gardés de France et formation aux premiers secours de leur gardien (une étude nationale descriptive)

Objectifs : L objectif principal était de dresser un état des lieux national, inexistant à ce jour, des capacités humaines et techniques à répondre à un problème médical au refuge. Type d étude : Nous avons conduit une étude descriptive prospective au printemps 2013 au travers d un questionnaire auto-administré auprès de l ensemble des gardiens. Matériel et méthode : Un taux de réponse de 69,5% a permis l analyse d un échantillon représentatif de 156 refuges. L analyse a porté sur la trousse à pharmacie, le défibrillateur, et la formation des gardiens. Résultats : Une typologie des refuges a été établie. Il existait une corrélation entre altitude et fréquentation des refuges (coefficient de 0,34 : p-value < 0.0001). Le taux d équipement en trousse à pharmacie était de 95% et il existait une tendance à l augmentation de son utilisation avec l altitude. Le taux d équipement en défibrillateur était de 26%. Les refuges de plus de 2400 mètres (OR 3,095 ; 1,079 à 8,877 ; p=0,036) et les plus fréquentés (OR 1,707 ; IC 1,156 à 2,520 : p=0,007) étaient les mieux équipés. Quatre-vingts six pour cent des gardiens étaient formés et 44 % avaient suivi une formation pratique dans les 12 derniers mois. Conclusion : L équipement médical et la formation des gardiens étaient importants mais hétérogène. L adaptation de la trousse à pharmacie à la typologie des refuges établie est nécessaire et doit être évaluée. La formation mériterait d être précisée sur son adéquation avec les problématiques du milieu montagnard en articulant les questions de prévention et de secours.Objective: The goal of this study was to establish a so far nonexistent picture of technical and human capacities to deal with medical situations. Methods: A descriptive prospective study was conducted from April to June 2013 by sending questionnaires to all hut keepers. A 69.5 % participation rate enabled us to analyse a representative sample of 156 mountain huts. Analysis covered first aid kits, defibrillators, and first aid training of hut keepers. Results: Analysis of altitude and use of huts distinguished high altitude and medium altitude huts and technical huts. First aid kit equipment rate was 95 % and there was an increasing trend of its use in higher altitudes (p=0,004). Defibrillator equipment rate was 26 %. The better equipped huts were those above 2400 meters (OR 3,095; 1,079 à 8,877; p=0,036) and the busier (OR 1,707; IC 1,156 à 2,520: p=0,007). Eighty-six percent of the hut keepers were trained in first aid and 44 % were trained during the last 12 months. Conclusions: Heterogeneous and extensive medical equipment has been described. The improvement of first aid kit according to the established typology is necessary and has to be assessed. Hut keepers' training, focusing on prevention and first aid, should be clarified for the specific mountain environment.GRENOBLE1-BU Médecine pharm. (385162101) / SudocSudocFranceF

Risk of cancer in the vicinity of municipal solid waste incinerators: importance of using a flexible modelling strategy

<p>Abstract</p> <p>Background</p> <p>We conducted an ecological study in four French administrative departments and highlighted an excess risk in cancer morbidity for residents around municipal solid waste incinerators. The aim of this paper is to show how important are advanced tools and statistical techniques to better assess weak associations between the risk of cancer and past environmental exposures.</p> <p>Methods</p> <p>The steps to evaluate the association between the risk of cancer and the exposure to incinerators, from the assessment of exposure to the definition of the confounding variables and the statistical analysis carried out are detailed and discussed. Dispersion modelling was used to assess exposure to sixteen incinerators. A geographical information system was developed to define an index of exposure at the IRIS level that is the geographical unit we considered.</p> <p>Population density, rural/urban status, socio-economic deprivation, exposure to air pollution from traffic and from other industries were considered as potential confounding factors and defined at the IRIS level. Generalized additive models and Bayesian hierarchical models were used to estimate the association between the risk of cancer and the index of exposure to incinerators accounting for the confounding factors.</p> <p>Results</p> <p>Modelling to assess the exposure to municipal solid waste incinerators allowed accounting for factors known to influence the exposure (meteorological data, point source characteristics, topography). The statistical models defined allowed modelling extra-Poisson variability and also non-linear relationships between the risk of cancer and the exposure to incinerators and the confounders.</p> <p>Conclusion</p> <p>In most epidemiological studies distance is still used as a proxy for exposure. This can lead to significant exposure misclassification. Additionally, in geographical correlation studies the non-linear relationships are usually not accounted for in the statistical analysis. In studies of weak associations it is important to use advanced methods to better assess dose-response relationships with disease risk.</p

The 236U neutron capture cross-section measured at the n-TOF CERN facility

The 236U isotope plays an important role in nuclear systems, both for future and currently operating ones. The actual knowledge of the capture reaction of this isotope is satisfactory in the thermal region, but it is considered insufficient for Fast Reactor and ADS applications. For this reason the 236U(n, γ) reaction crosssection has been measured for the first time in the whole energy region from thermal energy up to 1 MeV at the n TOF facility with two different detection systems: an array of C6D6 detectors, employing the total energy deposited method, and a 4π total absorption calorimeter (TAC), made of 40 BaF2 crystals. The two n TOF data sets agree with each other within the statistical uncertainty in the Resolved Resonance Region up to 800 eV, while sizable differences (up to 20%) are found relative to the current evaluated data libraries. Moreover two new resonances have been found in the n TOF data. In the Unresolved Resonance Region up to 200 keV, the n TOF results show a reasonable agreement with previous measurements and evaluated data

Erbium emission in MOS light emitting devices: from energy transfer to direct impact excitation

The electroluminescence (EL) at 1.54 µm of metal-oxide-semiconductor (MOS) devices with Er3+ ions embedded in the silicon-rich silicon oxide (SRSO) layer has been investigated under different polarization conditions and compared with that of erbium doped SiO2 layers. EL time-resolved measurements allowed us to distinguish between two different excitation mechanisms responsible for the Er3+ emission under an alternate pulsed voltage signal (APV). Energy transfer from silicon nanoclusters (Si-ncs) to Er3+ is clearly observed at low-field APV excitation. We demonstrate that sequential electron and hole injection at the edges of the pulses creates excited states in Si-ncs which upon recombination transfer their energy to Er3+ ions. On the contrary, direct impact excitation of Er3+ by hot injected carriers starts at the Fowler-Nordheim injection threshold (above 5 MV cm−1) and dominates for high-field APV excitation

Enrichment of low-frequency functional variants revealed by whole-genome sequencing of multiple isolated European populations

The genetic features of isolated populations can boost power in complex-trait association studies, and an in-depth understanding of how their genetic variation has been shaped by their demographic history can help leverage these advantageous characteristics. Here, we perform a comprehensive investigation using 3,059 newly generated low-depth whole-genome sequences from eight European isolates and two matched general populations, together with published data from the 1000 Genomes Project and UK10K. Sequencing data give deeper and richer insights into population demography and genetic characteristics than genotype-chip data, distinguishing related populations more effectively and allowing their functional variants to be studied more fully. We demonstrate relaxation of purifying selection in the isolates, leading to enrichment of rare and low-frequency functional variants, using novel statistics, DVxy and SVxy. We also develop an isolation-index (Isx) that predicts the overall level of such key genetic characteristics and can thus help guide population choice in future complex-trait association studies.Peer reviewe