Search results for "Complex Mixture"
showing 10 items of 826 documents
atzgene expressions during atrazine degradation in the soil drilosphere
2010
One of the various ecosystemic services sustained by soil is pollutant degradation mediated by adapted soil bacteria. The pathways of atrazine biodegradation have been elucidated but in situ expression of the genes involved in atrazine degradation has yet to be demonstrated in soil. Expression of the atzA and atzD genes involved in atrazine dechlorination and s-triazine ring cleavage, respectively, was investigated during in situ degradation of atrazine in the soil drilosphere and bulked samples from two agricultural soils that differed in their ability to mineralize atrazine. Interestingly, expression of the atzA gene, although present in both soils, was not detected. Atrazine mineralizati…
SOILS AND PLANTS IN AN ANTHROPOGENIC DUMP OF THE KOKDZHON PHOSPHORITE MINE (KAZAKHSTAN)
2017
Soil development is a crucial aspect in the process of mine spoil restoration and is also critical for the establishment of the vegetation. In this short paper, we present the features of mine proto-soils (i.e. soils at the early stage of development) and the natural vegetation species colonizing mine sites in a dry arid environment of Kazakhstan characterized by surface disturbance due to mine activity to access phosphorite deposit. These disturbed soils showed morphological features very different from each other (particularly horizons depth and sequence), even if the main chemical features were quite homogeneous. This is reasonably linked to the features of the Human Transported Material…
Modeling of biomass smoke injection into the lower stratosphere by a large forest fire (Part II): Sensitivity studies
2006
Abstract. The Chisholm forest fire that burned in Alberta, Canada, in May 2001 resulted in injection of substantial amounts of smoke into the lower stratosphere. We used the cloud-resolving plume model ATHAM (Active Tracer High resolution Atmospheric Model) to investigate the importance of different contributing factors to the severe intensification of the convection induced by the Chisholm fire and the subsequent injection of biomass smoke into the lower stratosphere. The simulations show strong sensitivity of the pyro-convection to background meteorology. This explains the observed coincidence of the convective blow-up of the fire plume and the passage of a synoptic cold front. Furthermor…
Direct Observation of Nanometer-Scale Pores of Melittin in Supported Lipid Monolayers
2015
Melittin is the most studied membrane-active peptide and archetype within a large and diverse group of pore formers. However, the molecular characteristics of melittin pores remain largely unknown. Herein, we show by atomic force microscopy (AFM) that lipid monolayers in the presence of melittin are decorated with numerous regularly shaped circular pores that can be distinguished from nonspecific monolayer defects. The specificity of these pores is reinforced through a statistical evaluation of depressions found in Langmuir-Blodgett monolayers in the presence and absence of melittin, which eventually allows characterization of the melittin-induced pores at a quantitative low-resolution leve…
Molecular biomass and MetaTaxogenomic assessment of soil microbial communities as influenced by soil DNA extraction procedure
2011
Three soil DNA extraction procedures (homemade protocols and commercial kit) varying in their practicability were applied to contrasting soils to evaluate their efficiency in recovering: (i) soil DNA and (ii) bacterial diversity estimated by 16S rDNA pyrosequencing. Significant differences in DNA yield were systematically observed between tested procedures. For certain soils, 10 times more DNA was recovered with one protocol than with the others. About 15,000 sequences of 16S rDNA were obtained for each sample which were clustered to draw rarefaction curves. These curves, as well as the PCA ordination of community composition based on OTU clustering, did not reveal any significant differenc…
Field and microcosm experiments to evaluate the effects of agricultural Cu treatment on the density and genetic structure of microbial communities in…
2006
The effects of Cu amendment on indigenous soil microorganisms were investigated in two soils, a calcareous silty clay (Ep) and a sandy soil (Au), by means of a 1-year field experiment and a two-month microcosm incubation. Cu was added as 'Bordeaux mixture' [CuSO(4), Ca(OH)(2)] at the standard rate used in viticulture (B1=16 kg Cu kg(-1) soil) and at a higher level of contamination (B3=48 kg Cu ha(-1) soil). More extractable Cu was observed in sandy soil (Au) than in silty soil (Ep). Furthermore, total Cu and Cu-EDTA declined with time in Au soil, whereas they remained stable in Ep soil. Quantitative modifications of the microflora were assessed by C-biomass measurements and qualitative modi…
Biogeochemical characterization of soils affected by more than 100 years of lead mining activity.
2020
<p>Mining has an adverse effect on soil quality as it is a source of heavy metal environmental pollution with direct consequences on its ecosystem services, especially those related to microbial activity. The magnitude and diversity of the impact produced by pollution is linked to the complexity and diversity of mining processes that share the same mining area. The soil will be modified, not only in the physicochemical characteristics but also physical alterations of varied typology will occur. All these changes and alterations related to mining activity are accompanied by changes in the composition, diversity and activity of soil microorganisms..<br>A study was…
Water-extractable organic matter linked to soil physico-chemistry and microbiology at the regional scale
2015
10 pages; International audience; A better understanding of the links between dissolved organic matter and biogeochemical processes in soil could help in evaluating global soil dynamics. To assess the effects of land cover and parental material on soil biogeochemistry, we studied 120 soil samples collected from various ecosystems in Burgundy, France. The potential solubility and aromaticity of dissolved organic matter was characterised by pressurised hot-water extraction of organic carbon (PH-WEOC). Soil physico-chemical characteristics (pH, texture, soil carbon and nitrogen) were measured, as was the δ13C signature both in soils and in PH-WEOC. We also determined bacterial and fungal abund…
"Table 2" of "Measurement of the inclusive jet cross-section in p anti-p collisions at s**(1/2) =1.96-TeV"
1970
Measured inclusive jet cross section as a function of jet transverse momentum for absolute values of the jet rapidity from 0.4 to 0.8 for cone radius R = 0.7.
"Table 6" of "Measurement of the inclusive jet cross-section in p anti-p collisions at s**(1/2) =1.96-TeV"
1970
Measured inclusive jet cross section as a function of jet transverse momentum for absolute values of the jet rapidity from 2.0 to 2.4 for cone radius R = 0.7.