The proliferation of quality labels for the same food product questions the relevance of labeling schemes. Based on the theory of legitimacy and research on food-related consumer behavior, this study aims to examine the influence of the perceived legitimacy of a label (PDO) on consumers' perceptions of the quality and purchase intentions of the labeled product. A conceptual model was, therefore, developed to estimate the influence of four dimensions of legitimacy on the perceived quality and purchase intention of PDO-labeled cheese, French cheeses being products whose quality is traditionally linked to their regional origin.
View Article and Find Full Text PDFContext: P-glycoprotein (P-gp) is a ubiquitous membrane detoxification pump involved in cellular defence against xenobiotics. Blood is a hub for the trade and transport of physiological molecules and xenobiotics. Our recent studies have highlighted the expression of a 140-kDa P-gp in brown trout erythrocytes in primary cell culture and its dose-dependent response to Benzo[a]pyrene pollutant.
View Article and Find Full Text PDFThe Algerian coastline is being exposed to several types of pollution, including that of hydrocarbons. This environment rich in oil could be the source of proliferation of hydrocarbonoclastic bacteria. The objective of the study is to isolate and identify indigenous bacterial strains from marine waters of two ports in the eastern Algerian coast and to test their growth in the presence of hydrocarbons with and without biostimulation throughout the intake of nitrogen and phosphate.
View Article and Find Full Text PDFIn aquatic organisms, such as fish, blood is continually exposed to aquatic contaminants. Multidrug Resistance (MDR) proteins are ubiquitous detoxification membrane pumps, which recognize various xenobiotics. Moreover, their expression is induced by a large class of drugs and pollutants.
View Article and Find Full Text PDFMicrocystis is a toxic freshwater cyanobacterium with an annual life cycle characterized by the alternation of a planktonic proliferation stage in summer and a benthic resting stage in winter. Given the importance of both stages for the development and the survival of the population, we investigated the genotypic composition of the planktonic and benthic Microcystis subpopulations from the Grangent reservoir (France) during two distinct proliferation periods. Our results showed a succession of different dominant genotypes in the sediment as well as in the water all along the study periods with some common genotypes to both compartments.
View Article and Find Full Text PDFBlood is a site of physiological transport for a great variety of molecules, including xenobiotics. Blood cells in aquatic vertebrates, such as fish, are directly exposed to aquatic pollution. P-gp are ubiquitous "membrane detoxification proteins" implicated in the cellular efflux of various xenobiotics, such as polycyclic aromatic hydrocarbons (PAHs), which may be pollutants.
View Article and Find Full Text PDFBackground: Western Balkan countries (WBCs) have a long-standing culinary tradition. The promotion of traditional foods may be a tool for coping with modernisation trends in such transition economies. This paper explores consumer preferences toward food in this region, focusing on a traditional fresh cow cheese locally called 'Mladi Sir'.
View Article and Find Full Text PDFMicrocystis colonies are known to overwinter on the surface of the sediment of freshwater ecosystems. However, little is known about the genotypic and toxicological dynamics of Microcystis populations during this benthic life stage. In this study, we report a two-year-long survey of benthic populations of Microcystis, which had spent from a few days to more than six years in the sediment.
View Article and Find Full Text PDFThe benthic recruitment of Microcystis was simulated in vitro in order to characterize the colonies of Microcystis recruited and to study the impact of intracellular and extracellular microcystins (MCs), and the influence of colony size on the recruitment process. We observed recruitment dynamics consisting of a lag phase followed by a peak and then a return to low recruitment rates, mainly controlled by passive resuspension throughout the experiment, and by physiological processes during the recruitment peak. Ninety-seven percent of the Microcystis colonies recruited were <160 μm in maximum length, and their cells contained much greater amounts of MCs (0.
View Article and Find Full Text PDFRecently, molecular environmental surveys of the eukaryotic microbial community in lakes have revealed a high diversity of sequences belonging to uncultured zoosporic fungi. Although they are known as saprobes and algal parasites in freshwater systems, zoosporic fungi have been neglected in microbial food web studies. Recently, it has been suggested that zoosporic fungi, via the consumption of their zoospores by zooplankters, could transfer energy from large inedible algae and particulate organic material to higher trophic levels.
View Article and Find Full Text PDFThis study presents a depth-related survey of virioplankton abundance in Lake Pavin (Massif Central, France), in relation to the abundances of heterotrophic prokaryotes, picocyanobacteria (Pcy), autotrophic picoeukaryotes (Peu), and of autotrophic (ANF) and heterotrophic (HNF) nanoflagellates. The sampling strategy was designed to be representative of the physico-chemical gradients of the whole water column of the lake, and the seasonal variability as well. In mixolimnic surface waters, all communities were present and viral abundance peaked in summer and autumn.
View Article and Find Full Text PDFEukaryotic microorganisms have been undersampled in biodiversity studies in freshwater environments. We present an original 18S rDNA survey of freshwater picoeukaryotes sampled during spring/summer 2005, complementing an earlier study conducted in autumn 2004 in Lake Pavin (France). These studies were designed to detect the small unidentified heterotrophic flagellates (HF, 0.
View Article and Find Full Text PDFFatty acid composition of the adipose tissue of six carnivorous mammalian species (European otter Lutra lutra, American mink Mustela vison, European Mink Mustela lutreola, European polecat Mustela putorius, stone marten Martes foina and European wild cat Felis silvestris) was studied. These species forage to differing degrees in aquatic and terrestrial food webs. Fatty acid analysis revealed significant differences in polyunsaturated fatty acid composition between species.
View Article and Find Full Text PDFIt is generally agreed that autotrophic organisms and especially phytoplanktonic species can be harmed by copper through its effect on photosystem. However, the impact of copper on other components of the pelagic food web, such as the microbial loop (autotrophic and heterotrophic picoplankton, pigmented and non-pigmented flagellates and ciliates) has received little attention. Indoor experiments were conducted to evaluate the direct and indirect effects of copper, supplied in the range of concentrations used to control cyanobacteria growth in ponds, on non-targeted organisms of natural microbial loop communities sampled in spring and summer.
View Article and Find Full Text PDFThis study presents an original 18S rRNA PCR survey of the freshwater picoeukaryote community, and was designed to detect unidentified heterotrophic picoflagellates (size range 0.6-5 microm) which are prevalent throughout the year within the heterotrophic flagellate assemblage in Lake Pavin. Four clone libraries were constructed from samples collected in two contrasting zones in the lake.
View Article and Find Full Text PDFCopper sulphate treatment is widely used as a global and empirical method to remove or control phytoplankton blooms without precise description of the impact on phytoplanktonic populations. The effects of two copper sulphate treatments on natural phytoplanktonic communities sampled in the spring and summer seasons, were assessed by indoor mesocosm experiments. The initial copper-complexing capacity of each water sample was evaluated before each treatment.
View Article and Find Full Text PDFThe composition, distribution and extracellular enzyme activities of bacteria attached to small (2-50 microm in size) transparent exopolymer and Coomassie-stained proteinaceous particles (TEP and CSP) were examined in two lakes of different trophic status located in the Massif Central of France. TEP concentrations (10(4)-10(6) particle per L) were significantly higher in the more productive lake and were significantly related to chlorophyll a concentrations. The majority of TEP and CSP were colonized by bacteria that constituted 2.
View Article and Find Full Text PDFDialysis bags were used to examine the impact of predation and viral lysis on prokaryotic community composition (PCC) over a 5-day experiment in the oligomesotrophic Lake Pavin (France). The impact of the different predator communities (protists and metazoans) of prokaryotes was estimated by water fractionation (<5 microm: treatment filtered on 5 microm, without ciliates and metazoans; UNF: unfiltered treatment with all planktonic communities). Enrichments of natural viruses (<1.
View Article and Find Full Text PDFThe effect of nutrient resources (N and P enrichment) and of different grazing communities on the prokaryotic community composition (PCC) was investigated in two freshwater ecosystems: Sep reservoir (oligomesotrophic) and lake Aydat (eutrophic). An experimental approach using microcosms was chosen, that allowed control of both predation levels, by size fractionation of predators, and resources, by nutrient amendments. Changes in PCC were monitored by fluorescent in situ hybridization (FISH) and terminal-restriction fragment length polymorphism (T-RFLP).
View Article and Find Full Text PDFFor aquatic systems, especially freshwaters, there is little data on the long-term (i.e., >6-month period) and depth-related variability of viruses.
View Article and Find Full Text PDFIEEE Trans Biomed Eng
March 2004
This article presents a new approach for detecting active sources in the cortex from magnetic field measurements on the scalp in magnetoencephalography (MEG). The solution of this ill-posed inverse problem is addressed within the framework of maximum entropy on the mean (MEM) principle introduced by Clarke and Janday. The main ingredient of this regularization technique is a reference probability measure on the random variables of interest.
View Article and Find Full Text PDFLittle is known about the structure of microbial communities in Sphagnum peatlands, and the potential effects of the increasing atmospheric CO2 concentration on these communities are not known. We analyzed the structure of microbial communities in five Sphagnum-dominated peatlands across Europe and their response to CO2 enrichment using miniFACE systems. After three growing seasons, Sphagnum samples were analyzed for heterotrophic bacteria, cyanobacteria, microalgae, heterotrophic flagellates, ciliates, testate amoebae, fungi, nematodes, and rotifers.
View Article and Find Full Text PDFAbundances of different compartments of the microbial loop (i.e., viruses, heterotrophic bacteria, nonpigmented nanoflagellates, and pigmented nanoflagellates), bacterial heterotrophic production (BHP), viral lysis, and potential flagellate grazing impacts on the bacterial assemblages were estimated during a short-term study (24 h) conducted in June 1998 in the epilimnion (5 m) and metalimnion (10 m) of a moderate-altitude oligomesotrophic lake (Lake Pavin, France).
View Article and Find Full Text PDFWater Environ Res
October 2001
Seasonal changes in size-fractionated alkaline phosphatase activity (APA) were studied in the hypereutrophic Villerest reservoir (Roanne, France) to determine whether the APA showed seasonal variations coupled to abiotic and biotic variables. Samples were collected at different depths from November 1992 to October 1993. The phosphatase activities were measured spectrophotometrically with pnitrophenyl phosphate as the substrate and related to protein concentrations.
View Article and Find Full Text PDFIn this study, we compared different methods-including transmission electron microscopy-and various nucleic acid labeling methods in which we used the fluorochromes 4',6'-diamidino-2-phenylindole (DAPI), 4-[3-methyl-2,3-dihydro-(benzo-1, 3-oxazole)-2-methylmethyledene]-1-(3'-trimethyl ammoniumpropyl)-quinilinium diioide (YOPRO-1), and SYBR Green I, which can be detected by epifluorescence microscopy (EM), for counting viruses in samples obtained from freshwater ecosystems whose trophic status varied and from a culture of T7 phages. From a quantitative and qualitative viewpoint, our results showed that the greatest efficiency for all ecosystems was obtained when we used the EM counting protocol in which YOPRO-1 was the label, as this fluorochrome exhibited strong and very stable fluorescence. A modification of the original protocol in which YOPRO-1 was used is recommended, because this modification makes the protocol faster and allows it to be used for routine analysis of fixed samples.
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