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Meskens G.,Cen Health | Meskens G.,Ghent University
Energy Strategy Reviews

The way nuclear energy technology 'escapes' a deliberate justification approach as an energy technology on a transnational level is today in sharp contrast with the way fossil fuel energy technologies are subject of global negotiations driven by the doom of climate change. The claim put forward is that this 'denial' is a symptom of a contemporary settled 'comfort of polarisation' around the use of nuclear energy technology that is deeply rooted in the organisational structures of politics, science and informed civil society. The article argues for the need to develop a new rationale that aims to seek societal trust 'by method instead of proof', taking into account that the outcome of such a justification process might as well be an acceptance or a rejection of the technology. It sketches what this 'deliberate-political' approach would be in theory and practice, briefly hits at two contemporary myths that would relativize the need for this approach and concludes with a 'pragmatic' list of elements of an advanced framework for deliberation on nuclear energy technology and on energy in general. © 2013 Elsevier Ltd. Source

Clauer N.,CNRS Hydrology and Geochemistry Laboratory of Strasbourg | Honty M.,Cen Health | Fallick A.E.,Scottish Universities Environmental Research Center | Sucha V.,Comenius University | Aubert A.,CNRS Hydrology and Geochemistry Laboratory of Strasbourg
Clay Minerals

Nanometre-sized illite-type crystals extracted from mixed-layer illite-smectite of cored bentonite beds from the East Slovak Basin were studied to investigate timing, duration and physical/chemical conditions of their nucleation and growth. The study includes application of the results to an evaluation of the regional extent of illitization. Close to salt-bearing formations, the nanometric particles underwent a more intense illitization, of identical duration, but with changing oxygen and hydrogen isotope characteristics of the parental brines. A comparison of the stratigraphic ages of the bentonite beds with the K-Ar ages of the authigenic crystals shows that illitization started during the Middle-Miocene Serravalian (Lower Sarmatian) subsidence that lasted from 17 to 11.5 Ma. Duration of illitization was bracketed between 14.5 and 9.0 Ma, with further episodes until recently at 0 Ma, depending on the geographic location of the host beds. The calculated subsidence rate varies from less than 300 m/Ma to more than 500 m/Ma and the thermal gradient ranges from ∼60°C/km to less than 50°C/km. The K-Ar ages of the nanometric illite point to either short-duration illitization when the onset was soon after sedimentation, or long-duration when the onset was significantly later after sedimentation. The illite δ18O varies little with increasing crystal size, whereas the δD changes significantly. In most samples the crystallization temperature determined by different criteria did not change significantly during crystal growth, but the oxygen and hydrogen isotopic compositions of the interacting fluids varied depending on sample location, immediate environment, timing and duration of illitization. The stable isotope composition of illite in bentonite beds with reduced fluid-rock ratios gives insight into the fluid-temperature regime of sedimentary basins through identifying local processes rather than wide-scale ones. Illitization is episodic with variable duration along different crystallization pathways, and to various extents in low-porosity, low-permeability bentonite beds. Depending on local conditions, illitization may vary even within apparently homogeneous beds. This contrasts with the situation for porous aquifers having large-scale fluid connectivity. © 2014 The Mineralogical Society. Source

Cerqueira G.M.,Instituto Butantan | McBride A.J.A.,Oswaldo Cruz Foundation | Hartskeerl R.A.,Cen Health | Ahmed N.,University of Hyderabad | And 4 more authors.

Background: Leptospirosis is one of the most widespread zoonoses in the world and with over 260 pathogenic serovars there is an urgent need for a molecular system of classification. The development of multilocus sequence typing (MLST) schemes for Leptospira spp. is addressing this issue. The aim of this study was to identify loci with potential to enhance Leptospira strain discrimination by sequencing-based methods. Methodology and Principal Findings: We used bioinformatics to evaluate pre-existing loci with the potential to increase the discrimination of outbreak strains. Previously deposited sequence data were evaluated by phylogenetic analyses using either single or concatenated sequences. We identified and evaluated the applicability of the ligB, secY, rpoB and lipL41 loci, individually and in combination, to discriminate between 38 pathogenic Leptospira strains and to cluster them according to the species they belonged to. Pairwise identity among the loci ranged from 82.0-92.0%, while interspecies identity was 97.7-98.5%. Using the ligB-secY-rpoB-lipL41 superlocus it was possible to discriminate 34/38 strains, which belong to six pathogenic Leptospira species. In addition, the sequences were concatenated with the superloci from 16 sequence types from a previous MLST scheme employed to study the association of a leptospiral clone with an outbreak of human leptospirosis in Thailand. Their use enhanced the discriminative power of the existing scheme. The lipL41 and rpoB loci raised the resolution from 81.0-100%, but the enhanced scheme still remains limited to the L. interrogans and L. kirschneri species. Conclusions: As the first aim of our study, the ligB-secY-rpoB-lipL41 superlocus demonstrated a satisfactory level of discrimination among the strains evaluated. Second, the inclusion of the rpoB and lipL41 loci to a MLST scheme provided high resolution for discrimination of strains within L. interrogans and L. kirschneri and might be useful in future epidemiological studies. © 2010 Cerqueira, et al. Source

Cruz-Tapias P.,Tel Aviv University | Cruz-Tapias P.,Cen Health | Cruz-Tapias P.,El Rosario University | Blank M.,Tel Aviv University | And 2 more authors.
Current Opinion in Rheumatology

Purpose of review: To present scientific evidence supporting the infectious origin for the antiphospholipid syndrome (APS) by molecular mimicry between pathogens, infection and vaccination with β2-glycoprotein I (β2-GPI) molecule. Recent findings: APS is characterized by the presence of pathogenic autoantibodies against β2-GPI. The infection etiology of APS was well established. Likewise, a link between vaccination such as tetanus toxoid may trigger antibodies targeting tetanus toxoid and β2-GPI, due to molecular mimicry between the two molecules. During the years, the pathogenic potential of anti-tetanus toxoid antibodies cross reactive with β2-GPI were found to be pathogenic in animal models, inducing experimental APS. Summary: Accumulated evidence supports that the presence of anti-β2-GPI antibodies is associated with a history of infections and the main mechanism to explain this correlation is molecular mimicry. The relationship between tetanus toxoid vaccination and APS reveals a novel view on the autoimmune/autoinflammatory syndrome induced by adjuvants (ASIA). © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins. Source

Schneider S.,Cen Health | Schneider S.,Schlumberger | Jacques D.,Cen Health | Mallants D.,CSIRO
Soil Research

Modelling complex vadose-zone hydrological processes across a range of spatial scales requires models and hydraulic properties commensurate with the scale of investigation. This study investigates the ability of two conceptual models with contrasting complexity and parameter requirements to quantify accurately the one-dimensional water balance in a soil-vegetation-atmosphere (SVA) system. The two models tested were: (i) the mechanistic HYDRUS-1D model, which numerically solves the Richards equation for saturated-unsaturated water flow; and (ii) a compartment or budget model that includes simplified schemes for redistribution of water in the soil. We discuss model performance for parameter sets obtained by inverse modelling for an SVA system developed in a podzol soil with Scots pine vegetation in Belgium. Soil hydraulic properties were derived from field-based soil water content data collected at multiple depths in two lysimeters installed in the multi-layered forest soil and subject to atmospheric boundary conditions during nearly one full hydrological year. Parameter optimisation was based on a genetic algorithm including elitism as an operator for improving the search for optimal solutions with better performance scores. Four scenarios were developed to investigate (i) the impact of the type of conceptual flow model (mechanistic or compartment), and (ii) the effect of the degree of detail or granularity used to describe the soil profile, on the accuracy of inverse modelling (i.e. five or two material layers with different hydraulic properties or a homogeneous profile with effective properties). Results showed that for models with the same number of material layers as the number of pedogenic horizons in the soil profile, both conceptual models reasonably match the observed water contents at all depths. The mechanistic model implemented in HYDRUS-1D was the more accurate with root mean-square error (RMSE) values for water content based on all data ∼0.02cm3cm-3, whereas for the compartment model the RMSE was ∼0.03cm3cm-3. The results further illustrated that for a mildly heterogeneous soil (in terms of coefficient of variation for estimated hydraulic properties between soil horizons), the five-layer soil profile could be replaced by a single set of effective hydraulic properties with only a 35% reduction in performance compared with the five-layer mechanistic model. A functional evaluation of model performance using the cumulative annual drainage revealed overall good performance of the simplified models; drainage values calculated with the five-layer compartment model and the one- and two-layer mechanistic model were never more than 36% larger than their reference value. Global inverse parameter optimisation routines such as the genetic algorithm applied here are powerful tools to determine field-scale hydraulic properties of heterogeneous soil profiles for simple and complex models; model and parameter complexity can be customised depending on data availability and computational constraints. © CSIRO 2013. Source

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