51 resultados para Bruno Tait


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Antimony doped tin oxide (ATO) was studied as a support material for IrO2 in proton exchange membrane water electrolyser (PEMWE). Adams fusion method was used to prepare the IrO2-ATO catalysts. The physical and electrochemical characterisation of the catalysts were carried out using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), powder conductivity, cyclic voltammetry (CV) and membrane electrode assembly (MEA) polarisation. The BET surface area and electronic conductivity of the supported catalysts were found to be predominantly arisen from the IrO2. Supported catalyst showed higher active surface area than the pristine IrO2 in CV analysis with 85% H3PO4 as electrolyte. The MEA performance using Nafion®−115 membrane at 80 °C and atmospheric pressure showed a better performance for IrO2 loading ≥60 wt.% than the pristine IrO2 with a normalised current density of 1625 mA cm−2 @1.8 V for the 60% IrO2-ATO compared to 1341 mA cm−2 for the pristine IrO2 under the same condition. The higher performance of the supported catalysts was mainly attributed to better dispersion of active IrO2 on electrochemically inactive ATO support material, forming smaller IrO2 crystallites. A 40 wt.% reduction in the IrO2 was achieved by utilising the support material.

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Indium tin oxide (ITO) was used as a support for IrO2 catalyst in the oxygen evolution reaction. IrO2 nanoparticles were deposited in various loading on commercially available ITO nanoparticle, 17–28 nm in size using the Adam's fusion method. The prepared catalysts were characterised using X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The BET surface area of the support (35 m2/g) was 3 times lower than the unsupported IrO2 (112.7 m2/g). The surface area and electronic conductivity of the catalysts were predominantly contributed by the IrO2. The supported catalysts were tested in a membrane electrode assembly (MEA) for electrolyser operation. The 90% IrO2-ITO gave similar performance (1.74 V@1 A/cm2) to that of the unsupported IrO2 (1.73 V@1 A/cm2) in the MEA polarisation test at 80 °C with Nafion 115 membrane which was attributed to a better dispersion of the active IrO2 on the electrochemically inactive ITO support, giving rise to smaller catalyst particle and thereby higher surface area. Large IrO2 particles on the support significantly reduced the electrode performance. A comparison of TiO2 and ITO as support material showed that, 60% IrO2 loading was able to cover the support surface and giving sufficient conductivity to the catalyst.

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Understanding the links between genetic, epigenetic and non-genetic factors throughout the lifespan and across generations and their role in disease susceptibility and disease progression offer entirely new avenues and solutions to major problems in our society. To overcome the numerous challenges, we have come up with nine major conclusions to set the vision for future policies and research agendas at the European level.

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BACKGROUND: Experimental autoimmune encephalomyelitis (EAE) is an animal model of autoimmune inflammatory demyelination that is mediated by Th1 and Th17 cells. The transcription factor interferon regulatory factor 3 (IRF3) is activated by pathogen recognition receptors and induces interferon-beta production.

METHODS: To determine the role of IRF3 in autoimmune inflammation, we immunised wild-type (WT) and irf3-/- mice to induce EAE. Splenocytes from WT and irf3-/- mice were also activated in vitro in Th17-polarising conditions.

RESULTS: Clinical signs of disease were significantly lower in mice lacking IRF3, with reduced Th1 and Th17 cells in the central nervous system. Peripheral T-cell responses were also diminished, including impaired proliferation and Th17 development in irf3-/- mice. Myelin-reactive CD4+ cells lacking IRF3 completely failed to transfer EAE in Th17-polarised models as did WT cells transferred into irf3-/- recipients. Furthermore, IRF3 deficiency in non-CD4+ cells conferred impairment of Th17 development in antigen-activated cultures.

CONCLUSION: These data show that IRF3 plays a crucial role in development of Th17 responses and EAE and warrants investigation in human multiple sclerosis.

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Children consuming maize based foods in Tanzania may be exposed to multiple mycotoxins. We estimated co-exposures of aflatoxins with Deoxynivalenol (DON) and fumonisins for children in rural Tanzania. Food consumption by the children was estimated by twice administering a 24 h dietary recall questionnaire to mothers of 18-24 months old children in Kikelelwa village. Each mother also; provided a sample of maize based flour used for feeding her child in the previous day. Each child's body weight (bw) was measured by following standard procedures. Aflatoxins, DON and fumonisins were determined in each sample using validated HPLC methods. Exposures for a mycotoxin were estimated by multiplying flour consumption (g/child/kgbw/day) by its contamination (mu g/kg). Complete data were obtained for 41 children. Maize flour consumption ranged from 16 to 254 g/child/day. Thirteen (32%) of the 41 children consumed flour with detectable aflatoxin levels (range, 0.11-386 mu g/kg), resulting in exposures from 1 to 786 ng/kg bw/day. All these children exceeded the aflatoxins exposure of concern (0.017 ng/kg bw/day). Eighteen (44%) of the children consumed flour with detectable DON levels (57-825 mu g/kg) and 34(83%), detectable fumonisins levels (63-2284 mu g/kg), resulting in respective exposure ranges of 0.38-8.87 mu g/kg bw/day and 0.19-26.37 mu g/kg bw/day. Twelve (66%) of the DON exposed children and 56% of the fumonisins exposed children exceeded the respective provisional tolerable daily intakes of 1 mu g/kg bw and 2 ng/kg bw. Co-exposures for aflatoxins with both DON and fumonsins were determined in 10% of the 41 children. Co-exposures of aflatoxins with fumonisins alone were found in 29% and of fumonisins with DON alone in 41% of the children. The study showed that children consuming maize based complementary foods in Northern Tanzania are at a risk of exposure to multiple mycotoxins. We recommend adoption of appropriate measures to minimize exposures of multiple mycotoxins in Tanzania. (C) 2014 Elsevier Ltd. All rights reserved.

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This chapter provides an analysis of the European Court of Justice's Fundamental Rights Jurisprudence, focused on the potential of Member States to maintain any positive regulatory role in supporting citizens' autonomy on the one hand, and on the impact of the Court's case law on citizens' opportunities to actually enjoy human rights within societies (substantive autonomy). It first sketches the notion of autonomy which is proposed as base of fundamental rights protection and promotion within a social reality characterized by not democratically legitimated dominance based on wealth and economic power. It proceeds to contextualize ECJ case law on fundamental rights. This section starts with a quantitative appetizer, which will formalize some assumptions and test them on a total of 150 cases before the European judiciary. The paper then offers a more conceptual recount around fundamental rights to equality and non-discrimination on the one hand and around fundamental rights of workers to actively shape employment and labor relations on the other hand. In conclusion some suggestions are made of how ECJ fundamental rights doctrine could develop more positively in order to moderate diverging interests of different parts of the citizenry in protecting fundamental rights.

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Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species' threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project - and avert - future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups - including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems - http://www.predicts.org.uk). We make site-level summary data available alongside this article. The full database will be publicly available in 2015.

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As part of any drilling cuttings pile removal process the requirement for monitoring the release of contaminants into the marine environment will be critical. Traditional methods for such monitoring involve taking samples for laboratory analysis. This process is time consuming and only provides data on spot samples taken from a limited number of locations and time frames. Such processes, therefore, offer very restricted information. The need for improved marine sensors for monitoring contaminants is established. We report here the development and application of a multi-capability optical sensor for the real-time in situ monitoring of three key marine environmental and offshore/oil parameters: hydrocarbons, synthetic-based fluids and heavy metal concentrations. The use of these sensors will be a useful tool for real-time in situ environmental monitoring during the process of decommissioning offshore structures. Multi-capability array sensors could also provide information on the dispersion of contamination from drill cuttings piles either while they are in situ or during their removal.

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Issues surrounding the misuse of prohibited and licensed substances in animals destined for food production and performance sport competition continue to be an enormous challenge to regulatory authorities charged with enforcing their control. Efficient analytical strategies are implemented to screen and confirm the presence of a wide range of exogenous substances in various biological matrices. However, such methods rely on the direct measurement of drugs and/or their metabolites in a targeted mode, allowing the detection of restricted number of compounds. As a consequence, emerging practices, in particular the use of natural hormones, designer drugs and low-dose cocktails, remain difficult to handle from a control point of view. A new SME-led FP7 funded project, DeTECH21, aims to overcome current limitations by applying an untargeted metabolomics approach based on liquid chromatography coupled to high resolution mass spectrometry and bioinformatic data analysis to identify bovine and equine animals which have been exposed to exogenous substances and assist in the identification of administered compounds. Markerbased strategies, dealing with the comprehensive analysis of metabolites present in a biological sample (urine/plasma/tissue), offer a reliable solution in the areas of food safety and animal sport doping control by effective, high-throughput and sensitive detection of exogenously administered agents. Therefore, the development of the first commercially available forensic test service based on metabolomics profiling will meet 21st century demands in animal forensics.

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Ce numéro était déjà sous presse quand, le 13 novembre 2015, Paris était une nouvelle fois la cible d’attentats terroristes d’une ampleur sans précédent, faisant plus d’une centaine de morts. Le Président François Hollande parla cette fois, de manière répétée, d’‘un acte de guerre’. Des voix solidaires se sont élevées des quatre coins de la planète, soulignant bien que, à travers la France, ce sont bien les valeurs qu’elle représente et qu’elle partage avec nombre de pays que les assassins de Daech visaient. Parmi tous les messages de solidarité, il nous semble important de souligner celui d’Hassan Rohani, le Président iranien, et celui d’Abdelaziz Bouteflika, le Président algérien: immédiatement, le premier ‘condamn[ait] avec vigueur ces crimes contre l'humanité et présent[ait] [s]es condoléance au peuple français endeuillé et au gouvernement’; le second dénonçait sans réserve ‘cette horreur planifiée [qui] constitue un véritable crime contre l'humanité’. Quant à Anouar Kbibech, le nouveau président du Conseil français du culte musulman, il ‘condamn[ait] avec la plus grande vigueur ces attaques inqualifiables’ et ‘appel[ait] à se regrouper autour de ces valeurs qui font la France’. Plus que jamais, il faut éviter les amalgames pour ne pas faire le jeu des minorités extrémistes.

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Observational studies have reported different effects of adiposity on cardiovascular risk factors across age and sex. Since cardiovascular risk factors are enriched in obese individuals, it has not been easy to dissect the effects of adiposity from those of other risk factors. We used a Mendelian randomization approach, applying a set of 32 genetic markers to estimate the causal effect of adiposity on blood pressure, glycemic indices, circulating lipid levels, and markers of inflammation and liver disease in up to 67,553 individuals. All analyses were stratified by age (cutoff 55 years of age) and sex. The genetic score was associated with BMI in both nonstratified analysis (P = 2.8 × 10(-107)) and stratified analyses (all P < 3.3 × 10(-30)). We found evidence of a causal effect of adiposity on blood pressure, fasting levels of insulin, C-reactive protein, interleukin-6, HDL cholesterol, and triglycerides in a nonstratified analysis and in the <55-year stratum. Further, we found evidence of a smaller causal effect on total cholesterol (P for difference = 0.015) in the ≥55-year stratum than in the <55-year stratum, a finding that could be explained by biology, survival bias, or differential medication. In conclusion, this study extends previous knowledge of the effects of adiposity by providing sex- and age-specific causal estimates on cardiovascular risk factors.

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A randomized trial was carried out comparing cyclosporin A (CsA) and short-term methotrexate (MTX) versus CsA alone for graft versus host disease (GVHD) prophylaxis in patients with severe aplastic anemia (SAA) undergoing allogeneic bone marrow transplantation (BMT) from a compatible sibling. Seventy-one patients (median age, 19 years; range, 4-46 years) were randomized to receive either CsA and MTX or CsA alone for the first 3 weeks after BMT. Subsequently, both groups received CsA orally, with gradual drug reduction until discontinuation 8 to 12 months after BMT. Patients randomized in both arms had comparable characteristics and received the same preparative regimen (ie, cyclophosphamide 200 mg/kg over 4 days). The median time for neutrophil engraftment was 17 days (range, 11-31 days) and 12 days (range, 4-45 days) for patients in the CsA/MTX group and the CsA alone group, respectively (P =.01). No significant difference was observed in the probability of either grade 2, grade 3, or grade 4 acute GVHD or chronic GVHD developing in the 2 groups. The Kaplan-Meier estimates of 1-year transplantation-related mortality rates for patients given either CsA/MTX or CsA alone were 3% and 15%, respectively (P =.07). With a median follow-up of 48 months from BMT, the 5-year survival probability is 94% for patients in the CsA/MTX group and 78% for those in the CsA alone group (P =. 05). These data indicate that the use of CsA with MTX is associated with improved survival in patients with SAA who receive transplants from compatible siblings. (Blood. 2000;96:1690-1697)