Toxin Induction and Protein Extraction from Fusariumspp. Cultures for Proteomic Studies

Fusaria are filamentous fungi able to produce different toxins. Fusarium mycotoxins such as deoxynivalenol, nivalenol, T2, zearelenone, fusaric acid, moniliformin, etc... have adverse effects on both human and animal health and some are considered as pathogenicity factors. Proteomic studies showed to be effective for deciphering toxin production mechanisms (Taylor et al., 2008) as well as for identifying potential pathogenic factors (Paper et al., 2007, Houterman et al., 2007) in Fusaria. It becomes therefore fundamental to establish reliable methods for comparing between proteomic studies in order to rely on true differences found in protein expression among experiments, strains and laboratories. The procedure that will be described should contribute to an increased level of standardization of proteomic procedures by two ways. The filmed protocol is used to increase the level of details that can be described precisely. Moreover, the availability of standardized procedures to process biological replicates should guarantee a higher robustness of data, taking into account also the human factor within the technical reproducibility of the extraction procedure

FullSWOF: A software for overland flow simulation / FullSWOF : un logiciel pour la simulation du ruissellement

Overland flow on agricultural fields may have some undesirable effects such as soil erosion, flood and pollutant transport. To better understand this phenomenon and limit its consequences, we developed a code using state-of-the-art numerical methods: FullSWOF (Full Shallow Water equations for Overland Flow), an object oriented code written in C++. It has been made open-source and can be downloaded from http://www.univ-orleans.fr/mapmo/soft/FullSWOF/. The model is based on the classical system of Shallow Water (SW) (or Saint-Venant system). Numerical difficulties come from the numerous dry/wet transitions and the highly-variable topography encountered inside a field. It includes runon and rainfall inputs, infiltration (modified Green-Ampt equation), friction (Darcy-Weisbach and Manning formulas). First we present the numerical method for the resolution of the Shallow Water equations integrated in FullSWOF_2D (the two-dimension version). This method is based on hydrostatic reconstruction scheme, coupled with a semi-implicit friction term treatment. FullSWOF_2D has been previously validated using analytical solutions from the SWASHES library (Shallow Water Analytic Solutions for Hydraulic and Environmental Studies). Finally, FullSWOF_2D is run on a real topography measured on a runoff plot located in Thies (Senegal). Simulation results are compared with measured data. This experimental benchmark demonstrate the capabilities of FullSWOF to simulate adequately overland flow. FullSWOF could also be used for other environmental issues, such as river floods and dam-breaks.Comment: 9 page

Recherche sur les types de temps associes aux brises de mer

Les circulations de brise de mer favorisent l’apparition de types de temps relativement frais et humides mais le plus souvent ensoleillés sur les espaces côtiers par rapport aux régions intérieures. Une méthode d’identification des fronts de brise par télédétection a été appliquée à l’Europe de l’Ouest et au nord-est du Brésil, afin d’en calculer la fréquence d’apparition et la distance préférentielle de pénétration dans les terres aux heures chaudes de la journée. Le suivi des fronts de brise a été effectué durant la saison chaude en Europe occidentale (mai à septembre 2000) et la moins arrosée dans le Nord-Est du Brésil (septembre à décembre 2000). La distance de pénétration des fronts de brise varie en fonction de l’exposition de la côte aux vents dominants, en Europe comme au Brésil. Cependant, la succession de situations météorologiques variées impose des configurations diverses d’un mois à l’autre en Europe de l’Ouest, tandis de la régularité des alizés fait ressortir une plus grande permanence, dans l’espace et dans le temps, de la localisation des fronts de brise au nord-est du Brésil.The sea breeze circulations involve cool and damp but sunny weather types over coastal fringes compared to inland areas. A method of identification of the sea breeze fronts was performed and applied to Western Europe and North-eastern Brazil, in order to calculate the occurrence of sea breeze fronts during the warmest period of the day and to calculate the most frequent distance of inland penetration. The sea breeze front monitoring was carried out during the warm season in Western Europe (May-September 2000) and during the less rainy season in North-eastern Brazil (September-December 2000). In Europe and Brazil, the inland penetration of sea breeze fronts varied according to the exposure of the coast to the prevailing wind. The succession of varied meteorological situations involved varied spatial organisation of the sea breeze fronts in Western Europe, while the more regular trade winds circulation allowed a less variable space and time organisation of the sea breeze fronts in the northeast of Brazil

Organic Versus Conventional Farming: The Case of wheat Production in Wallonia (Belgium)

The environmental impact of wheat production was assessed through Life Cycle Assessment (LCA). Local data were collected to characterize Walloon conventional and organic wheat production systems. Two functional units (FU) were investigated: 1kg of wheat grains at 15% humidity and 1ha used for wheat cropping. An uncertainty analysis assessed the significance of differences between conventional and organic systems. Using 1kg of grains as FU, results are not significantly different in global warming and cumulative energy demand. Very highly significant differences for soil acidification and eutrophication, and significant differences for agricultural land occupation were found to be in favor of conventional wheat production. Due to the high yield level in conventional farming (8.5 t/ha at 15% humidity against 4.5 t/ha for organic wheat), organic winter wheat has an equivalent or even, in some impact categories, a higher impact than conventional winter wheat. Using 1ha as FU, organic production is less impacting than conventional production, except for soil acidification and eutrophication. The choice of the FU has proven to be very sensitive. This study could be improved by accounting for rotation effects, by using more specific models to calculate emissions due to organic and mineral fertilization, and by accounting for carbon storage in soil

Organic Versus Conventional Farming: The Case of wheat Production in Wallonia (Belgium)

The environmental impact of wheat production was assessed through Life Cycle Assessment (LCA). Local data were collected to characterize Walloon conventional and organic wheat production systems. Two functional units (FU) were investigated: 1kg of wheat grains at 15% humidity and 1ha used for wheat cropping. An uncertainty analysis assessed the significance of differences between conventional and organic systems. Using 1kg of grains as FU, results are not significantly different in global warming and cumulative energy demand. Very highly significant differences for soil acidification and eutrophication, and significant differences for agricultural land occupation were found to be in favor of conventional wheat production. Due to the high yield level in conventional farming (8.5 t/ha at 15% humidity against 4.5 t/ha for organic wheat), organic winter wheat has an equivalent or even, in some impact categories, a higher impact than conventional winter wheat. Using 1ha as FU, organic production is less impacting than conventional production, except for soil acidification and eutrophication. The choice of the FU has proven to be very sensitive. This study could be improved by accounting for rotation effects, by using more specific models to calculate emissions due to organic and mineral fertilization, and by accounting for carbon storage in soil

Organic Versus Conventional Farming: The Case of wheat Production in Wallonia (Belgium)

The environmental impact of wheat production was assessed through Life Cycle Assessment (LCA). Local data were collected to characterize Walloon conventional and organic wheat production systems. Two functional units (FU) were investigated: 1kg of wheat grains at 15% humidity and 1ha used for wheat cropping. An uncertainty analysis assessed the significance of differences between conventional and organic systems. Using 1kg of grains as FU, results are not significantly different in global warming and cumulative energy demand. Very highly significant differences for soil acidification and eutrophication, and significant differences for agricultural land occupation were found to be in favor of conventional wheat production. Due to the high yield level in conventional farming (8.5 t/ha at 15% humidity against 4.5 t/ha for organic wheat), organic winter wheat has an equivalent or even, in some impact categories, a higher impact than conventional winter wheat. Using 1ha as FU, organic production is less impacting than conventional production, except for soil acidification and eutrophication. The choice of the FU has proven to be very sensitive. This study could be improved by accounting for rotation effects, by using more specific models to calculate emissions due to organic and mineral fertilization, and by accounting for carbon storage in soil

Chemometric perspectives on plankton community responses to natural iron fertilisation over and downstream of the Kerguelen Plateau in the Southern Ocean

International audienceWe examined phytoplankton community responses to natural iron fertilisation at 32 sites over and downstream from the Kerguelen Plateau in the Southern Ocean during the austral spring bloom in October–November 2011. The community structure was estimated from chemical and isotopic measurements (particulate organic carbon – POC; 13C-POC; particulate nitrogen – PN; 15N-PN; and biogenic silica – BSi) on size-fractionated samples from surface waters (300, 210, 50, 20, 5, and 1 μm fractions). Higher values of 13C-POC (vs. co-located 13C values for dissolved inorganic carbon – DIC) were taken as indicative of faster growth rates and higher values of 15N-PN (vs. co-located 15N-NO3 source values) as indicative of greater nitrate use (rather than ammonium use, i.e. higher f ratios).Community responses varied in relation to both regional circulation and the advance of the bloom. Iron-fertilised waters over the plateau developed dominance by very large diatoms (50–210 μm) with high BSi / POC ratios, high growth rates, and significant ammonium recycling (lower f ratios) as biomass built up. In contrast, downstream polar frontal waters with a similar or higher iron supply were dominated by smaller diatoms (20–50 μm) and exhibited greater ammonium recycling. Stations in a deep-water bathymetrically trapped recirculation south of the polar front with lower iron levels showed the large-cell dominance observed on the plateau but much less biomass. Comparison of these communities to surface water nitrate (and silicate) depletions as a proxy for export shows that the low-biomass recirculation feature had exported similar amounts of nitrogen to the high-biomass blooms over the plateau and north of the polar front. This suggests that early spring trophodynamic and export responses differed between regions with persistent low levels vs. intermittent high levels of iron fertilisation

What causes the inverse relationship between primary production and export efficiency in the Southern Ocean?

The ocean contributes to regulating atmospheric CO2 levels, partly via variability in the fraction of primary production (PP) which is exported out of the surface layer (i.e. the e-ratio). Southern Ocean studies have found that, contrary to global scale analyses, an inverse relationship exists between e-ratio and PP. This relationship remains unexplained, with potential hypotheses being i) large export of dissolved organic carbon (DOC) in high PP areas, ii) strong surface microbial recycling in high PP regions and/ or iii) grazing mediated export varies inversely with PP. We find that the export of DOC has a limited influence in setting the negative e-ratio/PP relationship. However, we observed that at sites with low PP and high e-ratios, zooplankton mediated export is large and surface microbial abundance low suggesting that both are important drivers of the magnitude of the e-ratio in the Southern Ocean

The GEOTRACES Intermediate Data Product 2014

The GEOTRACES Intermediate Data Product 2014 (IDP2014) is the first publicly available data product of the international GEOTRACES programme, and contains data measured and quality controlled before the end of 2013. It consists of two parts: (1) a compilation of digital data for more than 200 trace elements and isotopes (TEIs) as well as classical hydrographic parameters, and (2) the eGEOTRACES Electronic Atlas providing a strongly inter-linked on-line atlas including more than 300 section plots and 90 animated 3D scenes. The IDP2014 covers the Atlantic, Arctic, and Indian oceans, exhibiting highest data density in the Atlantic. The TEI data in the IDP2014 are quality controlled by careful assessment of intercalibration results and multi-laboratory data comparisons at cross-over stations. The digital data are provided in several formats, including ASCII spreadsheet, Excel spreadsheet, netCDF, and Ocean Data View collection. In addition to the actual data values the IDP2014 also contains data quality flags and 1-? data error values where available. Quality flags and error values are useful for data filtering. Metadata about data originators, analytical methods and original publications related to the data are linked to the data in an easily accessible way. The eGEOTRACES Electronic Atlas is the visual representation of the IDP2014 data providing section plots and a new kind of animated 3D scenes. The basin-wide 3D scenes allow for viewing of data from many cruises at the same time, thereby providing quick overviews of large-scale tracer distributions. In addition, the 3D scenes provide geographical and bathymetric context that is crucial for the interpretation and assessment of observed tracer plumes, as well as for making inferences about controlling processes

Evolution temporelle de douze métaux (V, Cr, Mn, Co, Cu, Zn, Ag, Cd, Ba, Pb, Bi et U) et des isotopes du plomb dans les neiges de la terre de Coats (Antarctique) depuis les années 1830

This work shows that it is now possible to get reliable data on the occurrence of numerous heavy metals at ultra low levels in Antarctic snow, by combining ultra clean field sampling and laboratory subsampling procedures and the use of ultra sensitive analytical techniques such as ICP-SFMS and TIMS. It has allowed us to determine concentrations of twelve metals (V, Cr, Mn, Co, Cu, Zn, Ag, Cd, Ba, Pb, Bi et D) and lead isotopic composition in the ultra clean series of snow samples collected at Coats Land, in the Atlantic sector of Antarctica. This work presents a 150 years record of metal inputs from natural and anthropogenic sources to Antarctica from the 1830's to the early 1990's. Lead atmospheric pollution begins as early as the end of the 19th century, peaks during the 1970's-1980's and then faIls sharply during recent decades. Evolution in lead isotopic abundance shows that Pb inputs to Antarctica reflect a complex blend of contributions originating from the Southern part of South America and Australia. For Cr, Cu, Zn, Ag, Bi and D, concentrations in the snow show significant increases from 1950 to 1980. These enhancements which cannot be explained by variations in natural inputs, illustrate that atmospheric pollution for heavy metals linked with anthropogenic activities in the Southern Hemisphere countries such as for example ferrous and non-ferrous metal mining and smelting is really global. Study of the time period 1920-1990, has allowed us to detail short-term (intra and inter annual) heavy metals concentration's changes. The large short-term variability, observed in Coats Land snow, shows the complex patterns of metal inputs to Antarctica, associated for instance to changes in long-range transport processes from mid-latitude to polar zone and to variability in the different natural sources, such local volcanic activity, sea-salt spray or crustal dust inputs.Ce travail nous a permis de montrer qu'il était maintenant possible de déterminer de manière fiable de nombreux éléments métalliques dans les neiges Antarctiques à des niveaux de concentration extrêmement bas, en combinant des techniques de prélèvement ultra propres sur le terrain, des méthodes de préparation d'échantillon adaptées et des techniques d'analyse ultra sensibles comme l'ICP-SFMS ou la spectrométrie de masse à ionisation thermique. C'est ainsi que nous avons pu déterminer les concentrations de douze métaux (V, Cr, Mn, Co, Cu, Zn, Ag, Cd, Ba, Pb, Bi et U) et l'abondance isotopique du plomb dans l'excellente série d'échantillons prélevée en Terre de Coats, dans le secteur Atlantique du continent Antarctique. Les résultats obtenus nous ont permis de reconstituer l'évolution des apports naturels et anthropiques de métaux vers l'Antarctique, depuis les années 1830 jusqu'au début des années 1990. Ainsi pour Pb, la pollution commence dès la fin du 19ème Siècle, elle atteint son paroxysme aux alentours des années 1970-1980 pour redescendre ensuite au cours des décennies récentes. L'évolution des rapports isotopiques montre que les apports de plomb sont le résultat d'un mélange complexe de différentes contributions, provenant des pays d'Amérique du Sud et de l'Australie. Pour Cr, Cu, Zn, Ag, Bi et U, les concentrations dans la neige augmentent significativement à partir des années 1950. Cette évolution qui ne peut s'expliquer par des variations naturelles, démontre que la pollution atmosphérique pour ces métaux, en relation avec les activités anthropiques dans les pays de l'Hémisphère Sud comme par exemple la production des métaux ferreux et non-ferreux, a pris une ampleur globale. Une étude de la période 1920-1990, a permis de détailler l'évolution des concentrations en métaux, à l'échelle intra et inter annuelle. Les fortes variations enregistrées à Coats Land montrent que les apports de métaux sont complexes, associés aux processus de transport des moyennes latitudes vers la zone polaire mais aussi à la variabilité des différentes sources naturelles, comme le volcanisme local, les embruns marins ou les flux de poussières crustales