Search results for "iom"
showing 10 items of 14211 documents
Arbuscular mycorrhizal fungi altered the hypericin, pseudohypericin, and hyperforin content in flowers of Hypericum perforatum grown under contrastin…
2016
St. John's Wort (Hypericum perforatum) is a perennial herb able to produce water-soluble active ingredients (a.i.), mostly in flowers, with a wide range of medicinal and biotechnological uses. However, information about the ability of arbuscular mycorrhizal fungi (AMF) to affect its biomass accumulation, flower production, and concentration of a.i. under contrasting nutrient availability is still scarce. In the present experiment, we evaluated the role of AMF on growth, flower production, and concentration of bioactive secondary metabolites (hypericin, pseudohypericin, and hyperforin) of H. perforatum under contrasting P availability. AMF stimulated the production of aboveground biomass und…
sPlotOpen – An environmentally balanced, open‐access, global dataset of vegetation plots
2021
Datos disponibles en https://github.com/fmsabatini/sPlotOpen_Code
Biometric Fish Classification of Temperate Species Using Convolutional Neural Network with Squeeze-and-Excitation
2019
Our understanding and ability to effectively monitor and manage coastal ecosystems are severely limited by observation methods. Automatic recognition of species in natural environment is a promising tool which would revolutionize video and image analysis for a wide range of applications in marine ecology. However, classifying fish from images captured by underwater cameras is in general very challenging due to noise and illumination variations in water. Previous classification methods in the literature relies on filtering the images to separate the fish from the background or sharpening the images by removing background noise. This pre-filtering process may negatively impact the classificat…
Characterization of MRNP34, a novel methionine-rich nacre protein from the pearl oysters
2012
9 pages; International audience; Nacre of the Pinctada pearl oyster shells is composed of 98% CaCO(3) and 2% organic matrix. The relationship between the organic matrix and the mechanism of nacre formation currently constitutes the main focus regarding the biomineralization process. In this study, we isolated a new nacre matrix protein in P. margaritifera and P. maxima, we called Pmarg- and Pmax-MRNP34 (methionine-rich nacre protein). MRNP34 is a secreted hydrophobic protein, which is remarkably rich in methionine, and which is specifically localised in mineralizing the epithelium cells of the mantle and in the nacre matrix. The structure of this protein is drastically different from those …
Mineral phase in shell repair of Manila clam Venerupis philippinarum affected by brown ring disease.
2011
14 pages; International audience; The mineral phase of shell repair in the Manila clam Venerupis philippinarum affected by brown ring disease (BRD) was characterised at various scales and at various stages of shell repair by confocal Raman microspectrometry and scanning electron microscopy. Spherulitic and quadrangular aragonite microstructures associated with polyene pigments were clearly observed. Von Kossa staining showed that at the beginning of shell repair, hemocytes are filled with insoluble calcium carbonate salts in all fluids and then are transported toward the extrapallial fluids and the repair sites. Our analyses suggest that after a Vibrio tapetis attack and BRD deposit some cl…
The shell matrix of the pulmonate land snail Helix aspersa maxima.
2012
12 pages; International audience; In mollusks, the shell mineralization process is controlled by an array of proteins, glycoproteins and polysaccharides that collectively constitute the shell matrix. In spite of numerous researches, the shell protein content of a limited number of model species has been investigated. This paper presents biochemical data on the common edible land snail Helix aspersa maxima, a model organism for ecotoxicological purposes, which has however been poorly investigated from a biomineralization viewpoint. The shell matrix of this species was extracted and analyzed biochemically for functional in vitro inhibition assay, for amino acid and monosaccharides composition…
Shell repair process in the green ormer Haliotis tuberculata: a histological and microstructural study.
2008
In the present paper, juvenile and adult shells of the green ormer Haliotis tuberculata ('Oreille de Saint-Pierre') were perforated in a zone close to the shell edge and the shell repair process was followed at two levels: (1) by observing the histology of the calcifying mantle in the repair zone and (2) by analyzing with SEM the microstructure of the shell repair zone. Histological data clearly show the presence of calcium carbonate granules into the connective tissues, but not in the epithelial cells. This suggests that calcium carbonate granules are synthesized by sub-epithelial cells and actively transported through the epithelium to the repair zone, via a process which may be similar t…
Characterization and evolution of two bacteriome-inhabiting symbionts in cixiid planthoppers (Hemiptera: Fulgoromorpha: Pentastirini).
2009
International audience; Like other plant sap-sucking insects, planthoppers within the family Cixiidae (Insecta: Hemiptera: Fulgoromorpha) host a diversified microbiota. We report the identification and first molecular characterization of symbiotic bacteria in cixiid planthoppers (tribe: Pentastirini). Using universal eubacterial primers we first screened the eubacterial 16S rRNA sequences in Pentastiridius leporinus (Linnaeus) with PCR amplification, cloning, and restriction fragment analysis. We identified three main 16S rRNA sequences that corresponded to a Wolbachia bacterium, a plant pathogenic bacterium, and a novel gammaproteobacterial symbiont. A fourth bacterial species affiliated w…
No growth stimulation of Canada’s boreal forest under half-century of combined warming and CO 2 fertilization
2016
Considerable evidence exists that current global temperatures are higher than at any time during the past millennium. However, the long-term impacts of rising temperatures and associated shifts in the hydrological cycle on the productivity of ecosystems remain poorly understood for mid to high northern latitudes. Here, we quantify species-specific spatiotemporal variability in terrestrial aboveground biomass stem growth across Canada’s boreal forests from 1950 to the present. We use 873 newly developed tree-ring chronologies from Canada’s National Forest Inventory, representing an unprecedented degree of sampling standardization for a large-scale dendrochronological study. We find significa…
Fish introductions and light modulate food web fluxes in tropical streams: a whole-ecosystem experimental approach.
2016
Decades of ecological study have demonstrated the importance of top-down and bottom-up controls on food webs, yet few studies within this context have quantified the magnitude of energy and material fluxes at the whole-ecosystem scale. We examined top-down and bottom-up effects on food web fluxes using a field experiment that manipulated the presence of a consumer, the Trinidadian guppy Poecilia reticulata, and the production of basal resources by thinning the riparian forest canopy to increase incident light. To gauge the effects of these reach-scale manipulations on food web fluxes, we used a nitrogen (15 N) stable isotope tracer to compare basal resource treatments (thinned canopy vs. co…